Aortic root cannula for cardiopulmonary bypass

Abstract

To optimize intraoperative visualization of the mitral valve during intraoperative assessment of valvular regurgitation, a device according to the present invention provides an alternative method of filling the LV. The device can also provide direct coronary ostial and standard antegrade aortic root cardioplegia. A novel cannula is used in conjunction with the heart-lung machine during open-heart surgery. The device described herein features an additional port with extension tubing to be advanced through the aortic valve in a retrograde manner, resulting in an extended piece of tubing sitting in the left / right ventricle or coronary ostia. This new tubing can deliver cardioplegia or saline into the coronary ostia (cardioplegia) or left / right ventricle (saline). The coronary ostia are perfused thereafter with cardioplegia in standard fashion. The left / right ventricle may be distended with known pressure and / or volume, allowing the surgeon to assess the mitral valve in a hands-free and more physiologic loaded manner.

Description

AORTIC ROOT CANNULA FOR CARDIOPULMONARY BYPASSCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 648,471 filed on May 16, 2024, which is incorporated by reference, herein, in its entirety.FIELD OF THE INVENTION

[0002] The present invention relates generally to medical devices. More particularly, the present invention relates to an aortic root cannula for cardiopulmonary bypass.BACKGROUND OF THE INVENTION

[0003] Mitral regurgitation (MR) describes a group of conditions that result in backflow of blood from the left ventricle (LV) to the left atrium (LA) through a dysfunctional, leaky mitral valve. Conversely, diseases of the thoracic aorta and aortic valve (DTAAV) include aortic valve stenosis (AS), insufficiency (Al), aortic aneurysm (TAA), and aortic dissection (AD). The tricuspid valve represents the right-sided analogue of the mitral valve, and the pulmonary valve represents the right-sided analogue of the aortic valve. The tricuspid valve, like the mitral valve, may be regurgitant (TR). resulting in backflow of blood from the right ventricle (RV) to the right atrium (RA), requiring surgical correction.The standard of care for many patients with these conditions is open heart surgery wherein the patient’s breastbone is divided, the patient is connected to the heart-lung machine, the heart is stopped, and the operation is undertaken on a still and bloodless heart and aorta. Mitral valve repair is the preferred operation for MR: the left atrium is opened, and the diseased mitral valve is surgically repaired from the atrial side. Those who are not candidates for repair receive mitral valve replacement, performed with the same incision and exposure. DTAAV are addressed via aortic valve replacement (AVR), aortic valve repair (AVr), or thoracic aortic surgery. Tricuspid valve repair is performed in a similar manner to mitralvalve repair, except the right atrium - rather than the left atrium - is opened to expose the tricuspid valve.

[0004] Critical to the ability to perform an appropriate, long-lasting mitral valve repair is the ability to understand the diseased anatomy of the mitral valve, predominantly achieved through adequate surgeon visualization. While cardiac ultrasound is used preoperatively, surgeons rely on an intraoperative assessment of valvular function before and after repair are attempted, which occurs while the heart is paralyzed and empty. The assessment includes but is not limited to visual inspection of the valve, tactile inspection with the valve, and manipulation of the valve and its constituent components. This assessment may also inform the decision between valve repair versus replacement. The same principle is used in tricuspid valve surgery . Operations that involve repair, replacement, or other therapeutic manipulation of either the mitral or tricuspid valve use this method of intraoperative valvular assessment in order to guide intraoperative decision making.

[0005] At present, intraoperative valvular assessment is accomplished using a bulb syringe, filled with saline, that is placed through the mitral valve and is used to insufflate the LV. Once the surgeon believes the LV is adequately pressurized, the bulb syringe is removed and the mitral valve is evaluated: a competent valve should leak very little, while a regurgitant valve will leak saline. Unfortunately, the shortcomings of the bulb syringe method are multifold, and include: imprecise volume and pressure input into the left ventricle; inherent valvular regurgitation at the point of maximal volume and pressure in the left ventricle by placing the syringe through the diseased or freshly repaired valve; short interval of valve assessment due to limited volume of the bulb syringe; and that the bulb syringe always occupies at least one of the surgeon’s hands. There is often discordance betw een intraoperative assessment on the arrest heart with the bulb syringe and the post-CPBassessment of the valve using transesophageal echocardiography (TEE). Due to this discrepancy, operations are complicated by residual mitral regurgitation, for which a return onto CPB is required or else a suboptimal repair must be accepted. Multiple runs on and off CPB generally confer increased morbidity' and mortality risk to patients. These same principles apply to tricuspid valve surgery', involving distension of the RV.

[0006] Cardiopulmonary bypass (CPB) is an essential tool during open cardiac surgery. The goal of CPB is to provide the surgical team with a bloodless and stationary field to operate on (i.e. the heart is not filled with blood nor actively beating) while still providing reasonable blood flow to the patient’s body. The CPB circuit has many different components, but at its core, the patient’s venous blood is drained into a reservoir, given oxygen, and returned for arterial circulation.

[0007] For intracardiac surgery, including most valve repairs operations, a technique known as aortic cross-clamping must be performed. In the most common CPB cannula configuration, the return cannula (filled with oxygenated blood) is inserted into the ascending aorta. Aortic cross-clamping involves complete physical occlusion of the patient's aorta below' (proximal to) that aortic cannula. This clamping is done for two reasons: (1) it prevents backflow from the cannula going into the heart and coronary' arteries; and (2) the cross-clamp allows surgeons to administer cardioplegia - a high-potassium drug solution that causes electromechanical cardiac arrest. The use of cardioplegia cools and paralyzes the heart, reducing its metabolic demand drastically in order to reduce ischemic injury' as a result of the lack of native blood flow to the coronary' arteries which perfuse the heart. The use of cardioplegia is a component of myocardial protection, which aims to preserve heart muscle health during open heart surgery'.

[0008] Alternative extracorporeal circulation configurations may be used in specific circumstances, depending on the disease state. Examples include extracorporeal membrane oxygenation (ECMO) and isolated left heart bypass.

[0009] Cardioplegia may be administered through various routes, most commonly: (1) standard antegrade cardioplegia, wherein cardioplegia is delivered to the aortic root and proceeds down the coronary arteries in the setting of a distal cross-clamp and a proximal non- insufficient aortic valve; (2) retrograde cardioplegia, in which a cannula is placed into the coronary sinus ostium and delivered into the venous cardiac circulation; or (3) ostial cardioplegia, wherein cannulae are placed directly into left and right coronary artery ostia (openings), generally used in operations during which the aorta is opened. The route of cardioplegia depends on the surgical context, and multiple routes may be combined in one operation. Commonly, antegrade root cardioplegia is administered to obtain initial cardioplegic arrest, are which point the operation is undertaken and ostial or retrograde cardioplegia is used as maintenance. Each type of cardioplegia requires a different set of cannulae, necessitating multiple pieces of hardw are devoted to myocardial protection.

[0010] It would be advantageous to provide a more accurate method of testing valve competency while on CPB w ould, therefore, reduce the risk associated with mitral (and tricuspid) valve surgery. In conjunction, the ability- to deliver both standard antegrade root cardioplegia and ostial cardioplegia would be useful.SUMMARY OF THE INVENTION

[0011] The foregoing needs are met, to a great extent, by the present invention, wherein one aspect is a device for cardiac surgery including an advancement cannula. The advancement cannula comprises an elongate tube defining an intenor lumen. The device includescardioplegia delivery tubing. The cardioplegia delivery tubing defines an elongate interior lumen configured for delivery of cardioplegia. The device includes aortic root vent tubing. The aortic root vent tubing defines an elongate interior lumen. A tubing trifurcation connection is also included in the device. The tubing trifurcation connection is configured to provide an interface between the advancement cannula, cardioplegia delivery' tubing, and aortic root vent tubing. In the alternative embodiment of the device, the trifurcation connection is substituted for a bifurcation connection, which sen es as an interface between the advancement cannula and a combined tubing performing both cardioplegia delivery' and aortic root venting.

[0012] In accordance with an aspect of the present invention, the tubing trifurcation connection defines an interior lumen and wherein the interior lumen comprises a guide configured to navigate the advancement cannula. The device can include an aortic access port. The device includes a vent connection configured to allow proper connection to a cardiopulmonary' bypass machine. The device also includes a tube clamp configured for clamping the aortic root vent tubing when suction is not required. The device further includes an aortic access needle configured for creating an access point for the device to enter the aortic root. The advancement cannula can also be configured to deliver cardioplegia directly to the coronary' ostia in operations requiring an open aortic root.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings provide visual representations, which will be used to more fully describe the representative embodiments disclosed herein and can be used by those skilled in the art to better understand them and their inherent advantages. In these drawings, like reference numerals identify corresponding elements and:

[0014] FIG. 1 illustrates a perspective view of the aortic root cannula, according to an embodiment of the present invention.

[0015] FIGS. 2A and 2B illustrate perspective views of an aortic root cannula, according to an embodiment of the present invention.

[0016] FIGS. 3A-3J illustrate perspective and sectional views of an aortic root cannula, according to an embodiment of the present invention.

[0017] FIGS. 4A-4D illustrate perspective views of an aortic root cannula and its functionality, according to an embodiment of the present invention.

[0018] FIGS. 5A-5E depict the advancement cannula in detail, according to an embodiment of the present invention.

[0019] FIG. 6 illustrates an alternative embodiment wherein the cardioplegia and aortic root vent lines are combined and subsequently connected to a bifurcation connection rather than a trifurcation connection.DETAILED DESCRIPTION

[0020] The presently disclosed subject matter now will be described more fully hereinafter with reference to the accompanying Drawings, in which some, but not all embodiments of the inventions are show n. Like numbers refer to like elements throughout. The presently disclosed subject matter may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Indeed, many modifications and other embodiments of the presently disclosed subject matter set forth herein will come to mind to one skilled in the art to which the presently disclosed subject matter pertains having the benefit of the teachings presented in the foregoing descriptions and the associated Drawings. Therefore, it is to be understood that the presently disclosed subject matter is not to be limited to the specific embodiments disclosed and that modifications andother embodiments are intended to be included within the scope of the appended claims.

[0021] The following abbreviations are used throughout this document and are listed here for ease of reference:AoV - Aortic valveARC - Aortic root cannulaAVR - Aortic valve replacementAVr - Aortic valve repairCABG - Coronary artery bypass graftingCPB - Cardiopulmonary bypassDTAAV - Diseases of the thoracic aorta and aortic valveECMO - Extracorporeal membrane oxygenationEDP - End diastolic pressureEDV - End diastolic volumeLA - Left atriumLCC - Left coronary cusp (of aortic valve)LMCA - Left main coronary arteryLV - Left ventricleLVEDP - Left ventricular end diastolic pressureLVEDV - Left ventricular end diastolic volumeLVOT - Left ventricular outflow tractMR - Mitral regurgitationMV - Mitral valveMVr - Mitral valve repairMVR - Mitral valve replacementNCC - non-coronary cusp (of aortic valve)OTS - Off the shelf’PVL - Paravalvular leakRA - Right atriumRCA - Right coronary artery’RCC - Right coronary cusp (of aortic valve)RV - Right ventricleTEE - Transesophageal echocardiography7TTE - Transthoracic echocardiographyTR - Tricuspid regurgitationTVr - Tricuspid valve repairTVR - Tricuspid valve replacement

[0022] To optimize intraoperative visualization of the mitral valve during intraoperative assessment of valvular regurgitation, a device according to the present invention provides an alternative method of fdling the LV. The present invention represents a conduit that providescommunication between multiple regions of the heart and great vessels; the predominant embodiment is a device that features a novel cannula to be used in conjunction with the heartlung machine during open-heart surgery. The device described herein is a novel antegrade cardioplegia cannula, connected to the heart at the aortic root, that features an additional port with a set of extension tubing to be advanced through the aortic valve (crossing the valve) in a retrograde manner, resulting in an extended piece of tubing sitting in the left ventricle. This new tubing can deliver saline or other fluid into the left ventricle, distending it with a known pressure and / or volume, allowing the surgeon to assess the mitral valve in a hands-free and more physiologic loaded manner. An analogous operation is applied for assessment of the tricuspid valve: the device described herein may be inserted at the pulmonary artery root, after which the extension tubing may be advanced to cross the pulmonary’ valve in a retrograde manner in order to fill the right ventricle with saline or other fluid for assessment of the tricuspid valve. Additionally, the same extension tubing can alternatively be placed at the ostia of the coronary arteries for delivery' of direct coronary ostial cardioplegia during multiple operations, including but not limited to those requiring an open ascending aorta.

[0023] The present invention represents a fundamental change in the w ay that mitral valve surgery' is performed, because the current bulb syringe method is used by the vast majority' of surgeons based on textbooks, publication, interview s, training, and clinical experience. The bulb syringe has a number of issues associated with its use in mitral valve operations that the present invention addresses:(1) inherent leakiness in having something interface through the mitral valve during ventricular insufflation;(2) blocked surgeon view during ventricular insufflation;(3) unknown pressure and volume of fluid input; and(4) having to refill the syringe multiple times.In contrast, the present invention does not interface with the mitral valve at all which allows the surgeon to have highest possible visibility and room to do any valve manipulations. Additionally, the product is connected to the cardiopulmonary bypass machine there is no “refilling” since fluid is delivered via a pump, which also transmits continuous pressure and volume information. The same principles and disadvantages of current methods exist for tricuspid valve assessment and surgery. The present invention also combines functions of standard aortic root cannulae and ostial cardioplegia cannulae, reducing the number of tools necessary' for myocardial protection in open heart surgery.

[0024] Technologically, the present invention improves current aortic root cannulae commonly used in cardiac surgery. It is unique in its ability to cross the aortic valve and fill the left ventricle and / or cross the pulmonary valve and fill the right ventricle and / or deliver coronary ostial cardioplegia while maintaining the functions of contemporary aortic root cannulae. It represents a direct replacement for contemporary aortic root cannulae. In addition to supplying cardioplegia solution and vacuum suction to the aortic root, it also features an additional cannula that can be advanced across the aortic valve in a retrograde manner which can (1) sit at the left or right coronary ostia for cardioplegia delivery'; or (2) sit in the left ventricle, allowing for volume infiltration of the left ventricle for stress testing of the mitral valve both before and after surgical repair; or (3) sit in the right ventricle, allowing for volume infiltration of the right ventricle for stress testing of the tricuspid valve both before and after surgical repair.

[0025] FIG. 1 illustrates a perspective view of the aortic root cannula, according to an embodiment of the present invention. As illustrated in FIG. 1. the aortic root cannula 10includes a tubing trifurcation connection 12, an advancement cannula 14, cardioplegia delivery' tubing 16, and aortic root vent tubing 18. The tubing trifurcation connection 12 provides an interface between the aortic insertion and the three tubes: the advancement cannula 14, the cardioplegia tubing 16, and the aortic root vent tubing 18. The advancement cannula 14 is navigated through the device, aorta, and the aortic valve. This advancement cannula 14 also connects to the cardiopulmonary- bypass machine and can then be used to fill the left / right ventricle during valvular assessment or the coronary' ostia for direct cardioplegia delivery. The cardioplegia delivery' tubing 16 is an elongate tube defining an interior lumen connected to the cardiopulmonary bypass machine and is used for delivery cardioplegic solution to the aortic root. The aortic root vent tubing 18 is also an elongate tube defining an interior lumen connected to the cardiopulmonary bypass machine and is used for suction in the aortic root. The device 10 also includes an aortic access port 20. The aortic access port 20 is inserted into the aorta and is configured to be sutured into place to ensure stability of the device 10 yvhen in use. Tube clamp 22 is configured to clamp the root vent tubing 18, when no suction is required during the procedure. Vent connection 24 is configured to allow proper connection to the cardiopulmonary bypass machine. Additionally, an aortic access needle 26 is configured to create an access point for the device to enter the aortic root. The components of the device are formed from a biocompatible polymer, thermoplastic elastomer, or any other suitable biocompatible material known to or conceivable by one of skill in the art.

[0026] FIGS. 2A and 2B illustrate perspective views of an aortic root cannula, according to an embodiment of the present invention. The aortic root cannula illustrated in FIGS. 2A and 2B represents a direct replacement for the existing antegrade cardioplegia cannula. Therefore, the first function of the cannula is to deliver cardioplegia into the aortic root via a connection to the cardiopulmonary' bypass circuitry, as well as provide vacuum suction at the aortic root.The second (novel) function of the cannula is to provide an extension cannula intended to feed through the aortic valve into the left ventricle and / or through the pulmonary valve into the right ventricle. Deliver}7of fluid into the left / right ventricle can be performed in a handsfree and retrograde manner, leaving the mitral / tricuspid valve unobstructed during the period of assessment, and allowing for the surgeon to continuously assess the valve with both hands available while the respective ventricle is being distended with fluid. The third (novel) function of the cannula is the administration of direct coronary ostial cardioplegia. FIG. 2A illustrates the aortic root cannula of the present invention in its pre-insertion state, and FIG. 2B illustrates the aortic root cannula of the present invention in its post-insertion and aortic infiltration state.

[0027] FIGS. 3A-3J illustrate perspective and sectional views of an aortic root cannula, according to an embodiment of the present invention. The tubing trifurcation connection component 12 of the present invention was designed as depicted in FIGS. 3A-3D. This design maintains the initial functions of an aortic root cannula (cardioplegia delivery7and aortic root venting) while enabling the function of delivering saline directly to the left / right ventricle or direct delivery7of cardioplegia to the coronary7ostia. The tubing trifurcation connection 12 includes three ports for connecting the tubing. As illustrated in FIG. 3 A, central lumen 28 is configured for delivery' of cardioplegia, left lumen 30 is configured for the aortic vent, and right lumen 32 is configured for the advancement cannula. As illustrated in FIGS. 3B and 3D there is a guide 34 on the inner wall of the part, 180° from the advancement cannula lumen 32 of the trifurcation connection. This inner guide 34 (behaving like a bumper) helps guide the advancement cannula in the proper direction and optimizes the tactile feedback of the user. FIG. 3B illustrates the same orientation of FIG. 3 A in a semisectional line drawing to portray the internal architecture. FIG. 3D depicts a section view ofthe part along A-A for additional clarity regarding the internal architecture. FIGS. 3E and 3F illustrate the tubing trifurcation connection interfacing with the aortic access port 20. FIGS. 3G-3J illustrate an alternative embodiment for the inner guide.

[0028] FIGS. 4A-4D illustrate perspective views of an aortic root cannula and its functionality, according to an embodiment of the present invention. FIG. 4A illustrates preinsertion. where the needle is still in place. FIG. 4B illustrates post-insertion, where the needle is removed. FIGS. 4C and 4D illustrate the advancement cannula being guided through the device.

[0029] FIGS. 5A-5E depict the advancement cannula in detail. The advancement cannula 14 itself is a subassembly of three components: the cannula tip 36, the tubing 38, and the luer lock 40. The advancement cannula allows for three functions: (1) safe crossing of the aortic valve, with subsequent fluid delivery’ to the left ventricle; (2) safe crossing of the pulmonary valve, with subsequent fluid delivery’ to the right ventricle; and (3) direct delivery’ of cardioplegia at the ostia of the coronary arteries. FIGS. 5 A and 5B depict the tip 36 of the advancement cannula 14. The tip design optimizes the surgeon's ability to cross the aortic valve safely. The conical shape prevents direct point loads on the valve leaflet tissue and slowly opens the valve when advancing to mitigate any potential for damage. Furthermore, the cannula tip 36 serves to interface with the coronary’ artery ostia in an atraumatic fashion, allowing cardioplegia delivery while preventing leakage to the aortic root during fluid delivery’. FIGS. 5C and 5D illustrate the luer lock 40 at the proximal end of the cannula 14, allowing for easy attachment to the cardiopulmonary’ bypass machine. This luer lock 40 can be connected for saline or cardioplegia delivery’ for mitral / tricuspid or aortic applications, respectively. FIG. 5E illustrates the advancement cannula 14 in full, though its length islikely to be greater than what is depicted in the image, so as to allow for tension-free insertion into the left / right ventricle and coronary ostia.

[0030] FIG. 6 illustrates an alternative embodiment wherein the cardioplegia and aortic root vent lines are combined and subsequently connected to a bifurcation connection rather than a trifurcation connection. As illustrated in FIG. 6 the aortic root cannula 10 includes a tubing bifurcation connection 42. The tubing bifurcation connection 42 provides an interface between the aortic insertion and two tubes: the advancement cannula 14, the aortic tubing 44. The advancement cannula 14 is navigated through the device, aorta, and the aortic valve. This advancement cannula 14 also connects to the cardiopulmonary' bypass machine and can then be used to fill the left / right ventricle during valvular assessment or the coronary' ostia for direct cardioplegia delivery'. The aortic tubing 42 is an elongate tube defining an interior lumen connected to the cardiopulmonary' by pass machine and is used for delivery' cardioplegic solution to the aortic root and is connected to the cardiopulmonary' bypass machine and is used for suction in the aortic root. The device 10 also includes an aortic access port 20. The aortic access port 20 is inserted into the aorta and is configured to be sutured into place to ensure stability' of the device 10 when in use. Additionally, an aortic access needle 26 is configured to create an access point for the device to enter the aortic root. The components of the device are formed from a biocompatible polymer, thermoplastic elastomer, or any other suitable biocompatible material known to or conceivable by one of skill in the art.

[0031] The aortic root cannula is designed to be inserted into the aortic root (or pulmonary artery root) with the needle in place. Once the cannula is inserted and secured to the aortic root (or pulmonary artery root) (as described in Operative Workflow), the needle is removed. The proximal end of the cardioplegic tubing is connected to the cardiopulmonary bypassmachine. At this point, the advancement cannula can be manipulated through the device advanced to the coronary ostia, through the aortic valve into the left ventricle, or through the pulmonic valve into the right ventricle as required.

[0032] When being used for MVr: after being inserted into the LV, the advancement cannula serves to infiltrate saline into the LV until near-physiologic pressure and volume are achieved. Left end-diastolic pressure (LVEDP) and volume (LVEDV) represent benchmarks for maximal loading on the mitral valve. These measures are achieved quantitatively through use of pre-operative TTE and / or TEE and can therefore be targeted by the surgeon and perfusionist.When being used for TVr, the same principles are applied, using analogous right ventricular pressure and volume metrics. When being used for ostial cardioplegia: after being advanced into the aortic root, the surgeon holds the tip of the cannula at the ostium of the right or left coronary artery' and may deliver cardioplegia at the desired flow, pressure, or target volume.

[0033] When being used for MVr: LVEDP likely represents a more accurate benchmark of physiologic ventricular filling, since infiltration of saline at physiologic pressure is likely to open the AoV, allowing saline to enter into the aortic root, ascending aorta, and coronary arteries, thereby rendering the total volume of the ventricular-aortic system greater than the expected LVEDV. When being used for TVr, the same principles are applied, using analogous right ventricular pressure and volume metrics.

[0034] When being used for MVr: Once adequately filled, the surgeon is able to assess the mitral valve with use of both hands. Importantly, the surgeon may elect to continue infiltration of saline into the LV through the advancement cannula in order to prolong the interval of valvular assessment. This can be performed in advance of performing repair - inorder to accurately diagnose the defective anatomy of the diseased valve - or after performing repair, in order to accurately test the adequacy of repair. When being used for TVr, the same principles are applied, using analogous filling of the right ventricle.

[0035] Use of the device involves clinical expertise of surgeons, perfusionists, and operating room nurses. There are four primary clinical scenarios in which the surgeon may deploy the advancement cannula portion of the device. Other clinical workflows are possible depending on the nature of the operation and surgeon preference.

[0036] Regardless of the workflow chosen, it is imperative that the advancement cannula be placed with a high level of caution so as not to inadvertently injure the aortic valve, pulmonary valve, or coronary ostia. Furthermore, the aortic root cannula (herein ARC) can deploy saline or cardioplegia; irrespective of the solution chosen, a fluid temperature of approximately 4 degrees Celsius is recommended so as not to compromise myocardial protection.

[0037] The specific steps for insertion, advancement, and use for each of the most common clinical scenarios are described below. Steps for removal are included thereafter.

[0038] This scenario is for surgery of the thoracic aorta or aortic valve, or other operations requiring the need for direct coronary ostial cardioplegia delivery.1. Aortic and venous purse-string sutures are applied. Purse-string for the ARC is also applied.2. The aortic and venous cannulae are inserted and connected to respective CPB tubing. CPB is initiated.3. The surgeon then inserts ARC. Importantly, the advancement cannula is not yet deployed.4. The aortic cross-clamp is then applied. Antegrade cardioplegia deliver}' is initiated in standard fashion.5. Upon cardioplegic arrest and aortotomy, the coronary ostia are exposed. The advancement cannula of the ARC is then deployed, and the surgeon guides the advancement cannula into the right or left coronary' ostia, maintaining its position either by (1) manual hold, or (2) through securing the cannula with a stay suture.6. Direct coronary ostial cardioplegia may now be delivered.

[0039] This scenario is for MVr with or without concomitant coronary, tricuspid, and / or arrhythmia surgery.1. Aortic and venous purse-string sutures are applied. Purse-string for the ARC is also applied.2. The aortic and venous cannulae are inserted and connected to respective CPB tubing.Importantly, CPB is not yet initiated.3. The surgeon then inserts the ARC. Attention is directed to the TEE, and the advancement cannula is inserted with TEE guidance with the heart beating. The surgeon may use adjunctive manual techniques to distort the aortic valve annulus to simplify crossing of the advancement cannula.4. Thereafter, CPB is initiated, aortic cross-clamp is applied, and antegrade cardioplegia delivery is initiated.5. The cannula is now ready for use in mitral valve assessment. The primary advantage of this technique is the facility with which the aortic valve can be crossed since the beating heartnecessarily opens the aortic valve leaflets during systole. Advanced cannula will render aortic valve somewhat incompetent, meaning cardioplegia deliver may be slower and some cardioplegia will be wasted into the LV.

[0040] This scenario is for MVr with or without concomitant coronary, tricuspid, and / or arrhythmia surgery.1. Aortic and venous purse-string sutures are applied.2. The aortic and venous cannulae are inserted and connected to respective CPB tubing. CPB is initiated.3. The ARC purse-string is applied, and the cannula is inserted thereafter. The aortic crossclamp is applied, and antegrade cardioplegia delivery is initiated.4. When the mitral portion of the operation is undertaken, the left atrium is opened, and the mitral valve is exposed.5. The surgeon then inserts ARC. Attention is directed to the TEE, and the advancement cannula is inserted with TEE guidance with the arrested heart. If the aortic valve is inadequately open, infiltration of saline through the mitral valve with a bulb syringe may be necessary'. The surgeon may use adjunctive manual techniques to distort the aortic valve annulus to simplify crossing of the advancement cannula.6. The cannula is now ready for use in mitral valve assessment.The technique renders the early stages of the operation most expeditious.

[0041] This scenario is for MVr with surgery of the thoracic aorta and / or aortic valve.1. Aortic and venous purse-string sutures are applied.2. The aortic and venous cannulae are inserted and connected to respective CPB tubing. CPB is initiated.3. The ARC purse-string is applied, and the cannula is inserted thereafter. The aortic crossclamp is applied, and antegrade cardioplegia delivery is initiated.4. When the aortic portion of the operation is undertaken, the aorta is opened, and the aortic valve is exposed.5. The aortic valve is manipulated as needed based on the operation (ie. leaflets are excised is performing a standard AVR).6. When surgical manipulation of the aortic valve is complete, the advancement cannula is inserted under direct vision through the aortic valve.7. The cannula is now ready for use in mitral valve assessment. The surgeon may then complete the aortic portion of the operation or proceed to the mitral portion of the operation and return to the aortic portion thereafter, depending on nature of the operation and surgeon preference.This method is the easiest and safest during operations that involve aortotomy.

[0042] This scenario is for TVr with or without concomitant coronary, mitral, and / or arrhythmia surgery.1. Aortic and venous purse-string sutures are applied. Cardioplegia purse-string is applied. Purse-string for the ARC is also applied at the pulmonary artery root.2. The aortic and venous cannulae are inserted and connected to respective CPB tubing. The cardioplegia cannula of choice is also inserted and connected.Importantly, CPB is not yet initiated.3. The surgeon then inserts the ARC to the pulmonary artery root. Attention is directed to the TEE, and the advancement cannula is inserted with TEE guidance with the heart beating. The surgeon may use adjunctive manual techniques to distort the pulmonary’ valve annulus to simplify crossing of the advancement cannula.4. Thereafter, CPB is initiated, aortic cross-clamp is applied, and antegrade cardioplegia delivery is initiated.5. The cannula is now ready for use in tricuspid valve assessment. The primary advantage of this technique is the facility with which the pulmonary valve can be crossed since the beating heart necessarily opens the pulmonary valve leaflets during systole. Advanced cannula will render pulmonary valve somewhat incompetent, which is of no consequence in the arrested heart.

[0043] This scenario is for TVr with or without concomitant coronary, mitral, and / or arrhythmia surgery'.1. Aortic and venous purse-string sutures are applied. Cardioplegia purse-string is applied.2. The aortic and venous cannulae are inserted and connected to respective CPB tubing. CPB is initiated.3. The ARC purse-string is applied at the pulmonary’ artery root, and the cannula is inserted thereafter. The aortic cross-clamp is applied, and antegrade cardioplegia delivery is initiated.4. When the tricuspid portion of the operation is undertaken, the right atrium is opened, and the tricuspid valve is exposed.5. The surgeon then inserts ARC. Atention is directed to the TEE, and the advancement cannula is inserted with TEE guidance with the arrested heart. If the pulmonary valve is inadequately open, infiltration of saline through the tricuspid valve with a bulb syringe may be necessary7. The surgeon may use adjunctive manual techniques to distort the pulmonary7valve annulus to simplify crossing of the advancement cannula.6. The cannula is now ready for use in tricuspid valve assessment.The technique renders the early stages of the operation most expeditious.

[0044] The risk associated with cannula removal is minimal, and the conduct of removal is described below.1. Prior to removing the cannula from the aorta, the advancement cannula should be retracted to its original, shortened position at the aortic root.2. Thereafter, the cannula can be removed, and purse-string sutures tightened and tied in standard fashion.

[0045] It should be noted that the device of the present invention can be used to implement a number of medical and surgical procedures known to or conceivable by one of skill in the art. Several exemplary methods of use of the device of the present invention follow. These examples are included to further illustrate the invention and are not meant to be considered limiting.

[0046] In one exemplary method of use of the device of the present invention, the device can be used for filling the left ventricle with fluid for the assessment of anatomy of the mitralvalve, including but not limited to the mitral annulus, mitral leaflets, subvalvular apparatus, chordae tendineae, and papillary muscles. This method can include filling the left ventricle under a number of different surgical circumstances, including, but not limited to, when a patient is connected to cardiopulmonary' bypass or other form of extracorporeal circulation, has a decompressed heart not under cardioplegic arrest, has a decompressed heart under cardioplegic arrest. The method can include filling the left ventricle without non-fluid instrument contact with the mitral valve or its constituent elements. The method can include filling the left ventricle with retrograde directionality7(i.e. in the direction opposite from physiologic blood flow), namely originating from the left-sided cardiac circulation distal to the aortic valve. The method can include filling the left ventricle without introduction of additional surgical tools into the left atrium or compromise of mitral valve visualization compared to pre-assessment mitral valve visualization. The method can include distending the left ventricle to a known pressure, as continuously7determined via connection to cardiopulmonary bypass, continuously determined via connection to other instantaneous pressure measurement apparatus, or intermittently determined via connection to an intermittent pressure measurement apparatus.

[0047] The method can include delivery' of a known volume of fluid into the left ventricle, as continuously tabulated via connection to cardiopulmonary' bypass, or otherwise determined through other volume measurement system. The method can include delivering said fluid through the use of a roller pump via connection to cardiopulmonary' bypass, extracorporeal membrane oxygenation circuit, or other roller pumping apparatus. The method can include filling the left ventricle without episodic requirement for surgeon hand occupation at the time of ventricular filling. The method can include the manipulation of or active intervention to the mitral valve (or any of its constituent elements) during valvular pressurization.

[0048] In another exemplary method of use of the device of the present invention, a method of assessing the mitral valve includes fluid-induced pressurization of the left ventricle. This method can include fdling the left ventricle under a number of different surgical circumstances, including, but not limited to, when a patient is connected to cardiopulmonary' bypass or other form of extracorporeal circulation, has a decompressed heart not under cardioplegic arrest, has a decompressed heart under cardioplegic arrest. The method can include pressurization via connection to cardiopulmonary' bypass, extracorporeal membrane oxygenation circuit, or other roller pumping apparatus. The method can include filling the left ventricle without episodic requirement for surgeon hand occupation at the time of ventricular filling. The method can include the manipulation of or active intervention to the mitral valve (or any of its constituent elements) during valvular pressurization.

[0049] In another exemplary method of use of the device of the present invention, a method of using tubing to cross the aortic valve in a retrograde manner allows for direct access to the left ventricle. The method can include crossing the aortic valve via primary' cardiovascular entry' at the level of the aortic root or ascending aorta. The method can include crossing the aortic valve using manual or automatized advancement of said tubing towards the aortic valve. The can include crossing the aortic valve with tubing using transesophageal echocardiography as an assistive imaging modality. The method can also include crossing the aortic valve with tubing without using transesophageal echocardiography^ as an assistive imaging modality.

[0050] In another exemplary' method of use of the device of the present invention, a method includes delivering fluid across the aortic valve into the left ventricle. The method can include crossing the aortic valve in the setting of a patient connected to cardiopulmonary' bypass or other form of extracorporeal circulation. The method can include crossing theaortic valve in the setting of a decompressed heart not under cardioplegic arrest. The method can include crossing the aortic valve in the setting of a decompressed heart under cardioplegic arrest. The method can include atraumatic manipulation of the aortic valve leaflets in order to render the aortic valve temporarily incompetent.

[0051] In another exemplary method of use of the device of the present invention, a method includes delivering fluid to both the left ventricle and aortic root simultaneously. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporeal circulation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest. The method can include filling the left ventricle without episodic requirement for surgeon hand occupation at the time of ventricular filling. The method can include the manipulation of or active intervention to the mitral valve (or any of its constituent elements) during valvular pressurization.

[0052] In another exemplary method of use of the device of the present invention, a method includes delivering fluid to the aortic root and the right or left coronary ostium simultaneously. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporeal circulation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest.

[0053] In another exemplary method of use of the device of the present invention, a method includes delivering fluid to the left ventricle while simultaneously venting the aortic root. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporealcirculation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest. The method can include delivering fluid without episodic requirement for surgeon hand occupation at the time of ventricular filling. The method can include the manipulation of or active intervention to the mitral valve (or any of its constituent elements) during valvular pressurization.

[0054] In another exemplary method of use of the device of the present invention, a method includes delivering fluid to the left or right coronary artery ostium while simultaneously venting the aortic root. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporeal circulation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest. The method can include delivering fluid without episodic requirement for surgeon hand occupation at the time of ventricular filling. The method can include the manipulation of or active intervention to the mitral valve (or any of its constituent elements) during valvular pressurization.

[0055] In another exemplary method of use of the device of the present invention, a method includes filling the right ventricle with fluid for the assessment of anatomy of the tricuspid valve, including but not limited to the tricuspid annulus, tricuspid leaflets, subvalvular apparatus, chordae tendineae, and papillary' muscles. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporeal circulation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest. The method can include filling the right ventricle without non-fluid instrument contact with the tricuspid valve or its constituent elements. The method can include filling the right ventricle with retrograde directionality (i.e. in the direction opposite from physiologic blood flow),namely originating from the right-sided cardiac circulation distal to the pulmonary valve. The method can include fdling the right ventricle without introduction of additional surgical tools into the right atrium or compromise of tricuspid valve visualization compared to preassessment tricuspid valve visualization. The method can include distending the right ventricle to a known pressure, as continuously determined via connection to cardiopulmonary bypass, continuously determined via connection to other instantaneous pressure measurement apparatus, or intermittently determined via connection to an intermittent pressure measurement apparatus. The method can include delivery of a known volume of fluid into the right ventricle, as continuously tabulated via connection to cardiopulmonary bypass, or otherwise determined through other volume measurement system. The method can include delivering fluid through the use of a roller pump via connection to cardiopulmonary bypass, extracorporeal membrane oxygenation circuit, or other roller pumping apparatus. The method can include fdling the right ventricle without episodic requirement for surgeon hand occupation at the time of ventricular fdling. The method can include the manipulation of or active intervention to the tricuspid valve (or any of its constituent elements) during valvular pressurization.

[0056] In another exemplary' method of use of the device of the present invention, a method includes assessing the tricuspid via fluid-induced pressurization of the right ventricle. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporeal circulation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest. The method can include pressurization via connection to cardiopulmonary bypass, extracorporeal membrane oxygenation circuit, or other roller pumping apparatus. The method can include filling the right ventricle without episodicrequirement for surgeon hand occupation at the time of ventricular filling. The method can include the manipulation of or active intervention to the tricuspid valve (or any of its constituent elements) during valvular pressurization.

[0057] In another exemplary method of use of the device of the present invention, a method includes using tubing to cross the pulmonary valve in a retrograde manner in order to obtain direct access to the right ventricle. The method can include crossing the pulmonary valve via primary cardiovascular entry at the level of the pulmonary root or ascending aorta. The method can include crossing the pulmonary valve using manual or automatized advancement of said tubing towards the pulmonary' valve. The method can include crossing the pulmonary valve with tubing using transesophageal echocardiography as an assistive imaging modality7. The method can include crossing the pulmonary valve with tubing without using transesophageal echocardiography as an assistive imaging modality.

[0058] In another exemplary method of use of the device of the present invention, a method includes delivering fluid across the pulmonary valve into the right ventricle. The method can include delivering fluid in a number of settings, including but not limited to the patient being connected to cardiopulmonary bypass or other form of extracorporeal circulation, a decompressed heart not under cardioplegic arrest, and a decompressed heart under cardioplegic arrest. The method can include atraumatic manipulation of the pulmonary valve leaflets in order to render the pulmonary valve temporarily incompetent.

[0059] In some instances, a device of the present invention is packaged in conjunction with cardiac surgical implants that generally necessitate the use of intraoperative valvular assessment and / or delivery of ostial cardioplegia, including but not limited to valvularprostheses, annuloplasty rings, artificial chordae tendineae, commercial pericardial (or other material) patches, organic and inorganic graft materials, and / or sutures.

[0060] The proposed invention has successfully undergone initial benchtop testing wherein the left ventricle was filled. The product is designed in such a way that it can be used in conjunction with the cardiopulmonary bypass machine regardless of if the procedure is mitral valve related or not, allowing the present invention to act as a direct replacement for the aortic root cannulas currently on the market.

[0061] The many features and advantages of the invention are apparent from the detailed specification, and thus, it is intended by the appended claims to cover all such features and advantages of the invention which fall within the true spirit and scope of the invention.Further, since numerous modifications and variations will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation illustrated and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Claims

What is claimed is:A device for cardiac surgery comprising: What is claimed is:

1. A device for cardiac surgery comprising: an advancement cannula, wherein the advancement cannula comprises an elongate tube defining an interior lumen; cardioplegia delivery' tubing, wherein the cardioplegia deliver}' tubing defines an elongate interior lumen configured for deliver}' of cardioplegia; aortic root vent tubing, wherein the aortic root vent tubing defines an elongate interior lumen configured for suction of the aortic root; a tubing connection, wherein the tubing connection is configured to provide an interface between the advancement cannula, cardioplegia delivery' tubing, and aortic root vent tubing.

2. The device of claim 1 wherein the tubing trifurcation or bifurcation connection defines an interior lumen and wherein the interior lumen comprises a guide configured to navigate the advancement cannula.

3. The device of claim 1 further comprising an aortic access port.

4. The device of claim 1 further wherein the cardioplegia delivery' tubing comprises a connection configured to allow connection to a cardiopulmonary bypass machine.

5. The device of claim 1 wherein the advancement cannula comprises a connection configured to allow proper connection to a cardiopulmonary bypass machine.

6. The device of claim 1 wherein the aortic root vent tubing comprises a connection configured to allow proper connection to a cardiopul monary bypass machine.

7. The device of claim 1 further comprising a tube clamp configured for clamping the aortic root vent tubing when suction is not required.

8. The device of claim 1 further comprising an aortic access needle configured for creating an access point for the device to enter the aortic root.

9. The device of claim 1 further comprising placement of the advancement cannula across the aortic valve into the left ventricle to deliver fluid into the left ventricle for assessment of the mitral valve and / or other cardiac structures.

10. The device of claim 1 further comprising placement of the advancement cannula to deliver cardioplegia directly to the coronary ostia with an open aortic root.

11. The device of claim 1 wherein the device is configured to deliver fluid to the left ventricle and the aortic root simultaneously.

12. The device of claim 1 wherein the device is configured deliver fluid to the left ventricle and the right or left coronary ostium simultaneously.

13. The device of claim 1 wherein the device is configured to deliver fluid to the left ventricle and vent fluid from the aortic root simultaneously.

14. The device of claim 1 wherein the advancement cannula is configured to be placed across the pulmonary valve into the right ventricle to deliver fluid into the right ventricle for assessment of the tricuspid valve and / or other cardiac structures.

15. The device of claim 1 wherein the tubing connection comprises a trifurcation.

16. The device of claim 1 wherein the tubing connection comprises a bifurcation.

17. A method of aortic root access comprising:inserting an aortic root cannula into an aortic root (or pulmonary artery root) with a needle in place; connecting a cardioplegic tubing to a cardiopulmonary bypass machine; manipulating an advancement cannula through the aortic root cannula and advancing it to a coronary ostia, through the aortic valve into the left ventricle, or through the pulmonic valve into the right ventricle.

18. The method of claim 17 further comprising using the advancement cannula to infiltrate saline into an LV until near-physiologic pressure and volume are achieved19. The method of claim 17 further comprising using analogous right ventricular pressure and volume metrics.

20. The method of claim 17 further comprising allowing saline to enter into the aortic root, ascending aorta, and coronary arteries, thereby rendering the total volume of the ventricular- aortic system greater than the expected LVEDV.

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