Vena cava occlusion type ventricular assist system

Abstract

The invention discloses a vena cava occlusion type ventricular assist system. The vena cava occlusion type ventricular assist system comprises a balloon catheter device and a control processor. The balloon catheter device comprises a six-cavity catheter, and the six-cavity catheter is provided with a first balloon and a second balloon. The six-cavity catheter is provided with a first pressure cavity, a second pressure cavity, a third pressure cavity, a liquid conveying cavity, a gas conveying cavity and a heart monitoring cavity which are not communicated with one another. The near port of the first pressure cavity serves as a first pressure measuring port and is close to the far end of the first balloon. The near port of the second pressure cavity serves as a second pressure measuring port and is close to the near end of the first balloon. The near port of the third pressure cavity serves as a third pressure measuring port and is located at the near end of the six-cavity catheter. A near port of the infusion cavity serves as an infusion port and is located in the first balloon. The near port of the air delivery cavity serves as an air delivery port and is located in the second balloon. The heart monitoring cavity near port serves as a monitoring port and is arranged close to the far end of the second balloon. The problems that the blocking and emptying duration is fixed, and the treatment termination opportunity cannot be reasonably controlled are solved.

Description

Technical Field

[0001] This invention relates to a vena cava occlusion ventricular assist system, belonging to the technical field of ventricular assist devices. Background Technology

[0002] Patients with acute decompensated heart failure (ADHF) experience elevated cardiac filling pressure and congestion in the systemic and pulmonary circulation due to impaired cardiac function, resulting in symptoms such as dyspnea and lower extremity edema. Furthermore, the degree of congestion is a key factor in predicting short-term and long-term prognosis – approximately 60%-80% of patients still have persistent congestion at discharge, and these patients have significantly higher readmission and mortality rates.

[0003] Currently, the core goal of ADHF treatment is to reduce congestion, primarily through drug therapy and device-assisted therapy. Drug therapy typically uses diuretics (such as furosemide) and vasodilators as the basic regimen, but these methods have drawbacks, including slow onset of action (usually several hours to several days), and some patients failing to achieve target levels due to diuretic resistance. Furthermore, long-term use may exacerbate kidney damage. Device-assisted therapy generally employs techniques such as ultrafiltration and intra-aortic balloon counterpulsation (IABC), but both have limitations: ultrafiltration requires cardiopulmonary bypass, is complex to perform, and may lead to hypotension; IBC is mainly used to improve myocardial perfusion, but its direct effect on reducing cardiac filling pressure is very limited.

[0004] To address the need for "rapidly reducing cardiac filling pressure," vena cava occlusion technology has gained increasing attention. The superior vena cava (SVC) carries approximately one-third of the venous return to the heart; theoretically, occluding the SVC can reduce cardiac preload and lower right atrial and pulmonary circulation pressure. Existing SVC occlusion devices (such as the preCARDIA early system) employ a fixed occlusion-emptying cycle (e.g., 5-minute occlusion, 30-second emptying), which, while reducing filling pressure to some extent, has significant drawbacks: Unable to adapt to individual differences: Different patients have significantly different hemodynamic responses to SVC occlusion. For example, patients who are sensitive to occlusion may experience excessive SVC pressure (>30 mmHg) due to fixed duration, which increases the risk of vascular injury and cerebral hemorrhage; while patients with slow occlusion response may not be able to effectively reduce right atrial pressure (RAP) due to insufficient duration, thus affecting the treatment effect.

[0005] Inaccurate determination of treatment termination: Existing systems mostly rely on a single duration threshold (such as 24 hours) to determine the timing of termination, lacking assessment of "hemodynamic stability", which can easily lead to premature termination (insufficient treatment) or overtreatment (increasing the risk of complications). Summary of the Invention

[0006] To address the problems existing in the prior art, the present invention provides a vena cava occlusion ventricular assist system.

[0007] The present invention adopts the following technical solution: A superior vena cava (VCA) occlusion ventricular assist system includes a balloon catheter device and a control processor connected to the balloon catheter device. The balloon catheter device includes a six-lumen catheter with a first balloon positioned in the middle. The first balloon is placed 1-2 cm from the junction of the superior vena cava and the right atrium to occlude the superior vena cava. A second balloon is positioned near the proximal end of the six-lumen catheter and is placed within the pulmonary artery. The six-lumen catheter has three non-communicating pressure chambers: a first pressure chamber, a second pressure chamber, a third pressure chamber, an infusion chamber, a gas infusion chamber, and a cardiac monitoring chamber. The proximal port of the first pressure chamber serves as a first pressure measurement port near the distal end of the first balloon, where a first blood pressure sensor monitors the superior vena cava pressure. The proximal port of the second pressure chamber serves as... A second pressure measuring port is positioned near the proximal end of the first balloon to monitor right atrial pressure via a second blood pressure sensor; a third pressure chamber proximal port, serving as a third pressure measuring port, is located near the proximal end of the six-lumen catheter to monitor pulmonary artery pressure via a third blood pressure sensor; an infusion chamber proximal port, serving as an infusion port, is located within the first balloon to inflate or deflate the first balloon; a gas infusion chamber proximal port, serving as a gas infusion port, is located within the second balloon to inflate or deflate the second balloon; a cardiac monitoring chamber proximal port, serving as a monitoring port, is positioned near the distal end of the second balloon to monitor cardiac output via a thermistor placed at the monitoring port; the distal ports of the first pressure chamber, second pressure chamber, third pressure chamber, infusion chamber, gas infusion chamber, and cardiac monitoring chamber are connected to the tubing.

[0008] The advantages of this invention are: This invention monitors superior vena cava pressure using a first blood pressure sensor and right atrial pressure using a second blood pressure sensor. Therefore, based on the monitoring of superior vena cava and right atrial pressures, the first balloon allows for reasonable control of occlusion and emptying time. The occlusion status of the superior vena cava can be adjusted in real time according to the individual patient's hemodynamic characteristics. Furthermore, it can effectively control treatment duration, avoiding premature termination leading to insufficient treatment and overtreatment increasing the risk of complications. This meets the treatment needs of various patient types, including those sensitive to occlusion and those with slow occlusion response, while minimizing the risk of vascular damage and significantly improving treatment efficacy. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the balloon catheter device of the vena cava occlusion ventricular assist system of the present invention.

[0010] Figure 2 This is a schematic diagram of the cross-section of a six-lumen catheter.

[0011] Figure 3This is a schematic diagram of the usage status of the vena cava occlusion ventricular assist system of the present invention (first balloon inflated, second balloon collapsed).

[0012] Figure 4 This is a schematic diagram of the control processor.

[0013] Figure 5 This is a schematic diagram of another usage state of the vena cava occlusion ventricular assist system of the present invention (first balloon collapsed, second balloon inflated). Detailed Implementation

[0014] like Figures 1 to 5As shown, this invention proposes a superior vena cava occlusion ventricular assist system, which includes a balloon catheter device 100 and a control processor 300 connected to the balloon catheter device 100. The balloon catheter device 100 includes a six-lumen catheter 30, with a first balloon 10 located in the middle of the six-lumen catheter 30. The first balloon 10 is positioned 1-2 cm from the junction of the superior vena cava (SVC) and the right atrium (RA) to occlude the proximal end of the superior vena cava and reduce cardiac preload. A second balloon 20 is located near the proximal end of the six-lumen catheter 30 and is positioned within the pulmonary artery (PA). The six-lumen catheter 30 has non-interconnected... The system comprises six chambers: a first pressure chamber 31, a second pressure chamber 32, a third pressure chamber 33, an infusion chamber 34, a gas infusion chamber 35, and a cardiac monitoring chamber 36. The proximal port of the first pressure chamber 31 serves as the first pressure measuring port 301, located near the distal end of the first balloon 10. This first pressure measuring port 301 is placed within the superior vena cava to monitor the superior vena cava pressure (SVCp) using a first blood pressure sensor (not shown). The proximal port of the second pressure chamber 32 serves as the second pressure measuring port 302, located near the proximal end of the first balloon 10. This second pressure measuring port 302 is placed within the right atrium to monitor the right atrial pressure (RAP) using a second blood pressure sensor (not shown). The third pressure chamber 34... The proximal port of the pressure chamber 33 serves as the third pressure measuring port 303, located at the proximal end of the six-lumen catheter 30. This third pressure measuring port 303 is placed within the pulmonary artery to monitor pulmonary artery pressure (PAP) via a third blood pressure sensor (not shown). The proximal port of the infusion chamber 34 serves as the infusion port 305, located within the first balloon 10, for inflating and deflating the first balloon 10. After inflating the first balloon 10, the inflated balloon 10 occludes the superior vena cava. The proximal port of the gas infusion chamber 35 serves as the gas infusion port 306, located within the second balloon 20, for inflating and deflating the second balloon 20. After inflating the second balloon 20, the inflated balloon 20 allows blood flow through it. The guide automatically floats to the target position (without additional positioning operation), and after the second balloon 20 is deflated, the pulmonary artery pressure and cardiac output CO are measured. That is, the second balloon 20 plays an auxiliary role in measuring hemodynamic status. The proximal port of the cardiac monitoring chamber 36 is set as the monitoring port 304 near the distal end of the second balloon 20. The monitoring port 304 is used to be placed in the pulmonary artery, and the cardiac output is monitored by a thermistor (not shown) placed at the monitoring port 304. The first pressure chamber 31, the second pressure chamber 32, the third pressure chamber 33, the infusion chamber 34, the gas infusion chamber 35, and the distal port of the cardiac monitoring chamber 36 are each connected to a tube.

[0015] In actual implementation, the distal ends of the first pressure chamber 31, the second pressure chamber 32, the third pressure chamber 33, the infusion chamber 34, the gas infusion chamber 35, and the cardiac monitoring chamber 36 are located at the distal end of the six-lumen catheter 30. An injection head 101 is installed at the distal end of the six-lumen catheter 30, and the pipeline is connected to the injection head 101.

[0016] Preferably, the injection head 101 has a suture ring-shaped groove for fixing the balloon catheter device 100 in clinical use. The injection head 101 is made of medical-grade polyethylene or other medical polymer materials.

[0017] refer to Figures 1 to 3 The pipeline includes a first pressure measuring tube 40, a second pressure measuring tube 50, a third pressure measuring tube 60, an infusion tube 70, a gas infusion tube 80, and a cardiac monitoring tube 90. The first pressure measuring tube 40, the second pressure measuring tube 50, the third pressure measuring tube 60, the infusion tube 70, the gas infusion tube 80, and the cardiac monitoring tube 90 are respectively connected to the first pressure chamber 31, the second pressure chamber 32, the third pressure chamber 33, the infusion chamber 34, the gas infusion chamber 35, and the cardiac monitoring chamber 36.

[0018] In practical applications, one end of the first pressure measuring tube 40, the second pressure measuring tube 50, the third pressure measuring tube 60, the infusion tube 70, the gas infusion tube 80, and the heart monitoring tube 90 is connected to the injection head 101, while the other end is connected to a connector 102, such as... Figure 1 As shown. Further, the cable leading out from the thermistor is led out from the corresponding connector 102 via the cardiac monitoring chamber 36 and the cardiac monitoring tube 90, and physiological saline is injected into the cardiac monitoring chamber 36 and the cardiac monitoring tube 90.

[0019] In practical applications, thermistors should be equipped with an encapsulation cover to prevent direct contact with blood and thus avoid biocompatibility issues.

[0020] like Figure 2 , Figure 2 The six-lumen catheter section 30 shows six chambers. In actual design, the distribution of the six chambers is not restricted, and the cross-sectional size of the six chambers can be reasonably designed without limitation.

[0021] In the actual design, the first pressure measuring port 301, the second pressure measuring port 302, and the third pressure measuring port 303 are in direct contact with the blood, and their diameters are between 0.8mm and 1.2mm.

[0022] In the actual design, the surface of the first balloon 10 and the six-lumen catheter 30 is sealed to prevent the liquid inside the first balloon 10 from leaking out, and the surface of the second balloon 20 and the six-lumen catheter 30 is sealed to prevent the gas inside the second balloon 20 from leaking out.

[0023] In actual design, the monitoring port 304 comes into direct contact with the blood and has a diameter between 0.5mm and 1.0mm. Typically, the monitoring port 304 is designed in an elliptical shape.

[0024] like Figure 4The control processor 300 includes a housing, inside which are a processing module 3001, a gas drive module 3002, an electrical signal acquisition module 3004, a blood pressure signal acquisition module 3005, and a timing module 3006. Outside the housing is a liquid drive module 3003. The processing module 3001 is electrically connected to the gas drive module 3002, the electrical signal acquisition module 3004, the blood pressure signal acquisition module 3005, the liquid drive module 3003, and the timing module 3006. The gas drive module 3002 is connected to the gas delivery tube 80 connector 102 via a gas delivery extension tube. The liquid drive module 3003 is connected to the infusion tube 70 connector 102 via an infusion extension tube. An infusion interface 360 ​​on the liquid drive module 3003 is used to connect to the infusion extension tube. The electrical signal acquisition module 3004 is connected to a thermistor via a cable leading from the balloon catheter device 100. The blood pressure signal acquisition module 3005 is connected to the pressure measuring chips of the first blood pressure sensor, the second blood pressure sensor, and the third blood pressure sensor.

[0025] The first blood pressure sensor is connected sequentially to the first pressure measuring tube 40 and the first pressure chamber 31 via the first extension tube. When in use, saline solution is injected into the first blood pressure sensor, the first extension tube, the first pressure measuring tube 40, and the first pressure chamber 31. Similarly, the second blood pressure sensor is connected sequentially to the second pressure measuring tube 50 and the second pressure chamber 32 via the second extension tube. When in use, saline solution is injected into the second blood pressure sensor, the second extension tube, the second pressure measuring tube 50, and the second pressure chamber 32. Similarly, the third blood pressure sensor is connected sequentially to the third pressure measuring tube 60 and the third pressure chamber 33 via the third extension tube. When in use, saline solution is injected into the third blood pressure sensor, the third extension tube, the third pressure measuring tube 60, and the third pressure chamber 33.

[0026] The first, second, and third blood pressure sensors are existing invasive blood pressure sensors, each including a pressure-measuring chip housed within the sensor housing, and should be equipped with an infusion device and valve, etc. The pressure-measuring chip feeds back the monitored blood pressure signal to the blood pressure signal acquisition module 3005. The structure and blood pressure measurement principle of invasive blood pressure sensors are well-known technologies and will not be detailed here; blood pressure is generally between 10 kPa and 15 kPa.

[0027] In the actual design, the gas drive module 3002 includes a gas pump and a gas tank, and the processing module 3001 controls the operation of the gas pump to deliver gas or draw gas back. The liquid drive module 3003 includes an infusion pump and a liquid tank, and the processing module 3001 controls the operation of the infusion pump to deliver liquid or draw liquid back.

[0028] In practical applications, the housing also includes a storage module 3007, an alarm module 3008, a communication module 3009, and a power supply module 3010. The processing module 3001 is connected to the storage module 3007, the alarm module 3008, and the communication module 3009.

[0029] In the control processor 300, the power supply module 3010 is used to provide stable power to each module; the blood pressure signal acquisition module 3005 is used to acquire superior vena cava pressure via a first blood pressure sensor, right atrial pressure via a second blood pressure sensor, and pulmonary artery pressure via a third blood pressure sensor; the electrical signal acquisition module 3004 is used to acquire cardiac output via a thermistor; the gas drive module 3002 is used to inflate and deflate the second balloon 20; the liquid drive module 3003 is used to inflate and deflate the first balloon 10; the storage module 3007 is used to store the acquired signal data and programs; the timing module 3006 is used to control the duration of occlusion, evacuation, and treatment; the communication module 3009 is used to communicate with the operation panel; the alarm module 3008 may include a buzzer and an alarm light, used to trigger an audible and visual alarm in emergency situations such as abnormally high superior vena cava pressure; and the processing module 3001 is mainly used to control and coordinate the work between the modules, and to perform noise reduction and verification processing on the received signals.

[0030] In this invention, the end closer to the operator (such as a doctor or nurse) is defined as "far", while the end farther from the operator, that is, the end closer to the patient's heart, is defined as "proximal". Furthermore, for the balloon catheter device 100, the end that enters the patient first is defined as the proximal end, and the other end as the distal end.

[0031] When using the vena cava occlusion ventricular assist system of this invention: During the gradual inflation of the first balloon 10 to occlude the superior vena cava, the duration of occlusion is determined by calculating the rate of decrease in right atrial pressure (RAP-dp / dt) and the rate of increase in superior vena cava pressure (SVCp-dp / dt) within the first 120 seconds after occlusion, based on the superior vena cava pressure (SVCp) monitored by the first blood pressure sensor and the right atrial pressure (RAP) monitored by the second blood pressure sensor. Specifically, if RAP-dp / dt ≥ 0.05 mmHg... If the occlusion time is 3 minutes and SVCp-dp / dt ≤ 0.03 mmHg / s, then the occlusion time is set to 3 minutes; if 0.02 mmHg / s ≤ RAP-dp / dt < 0.05 mmHg / s, then the occlusion time is set to 4-5 minutes (adjusted by fine-tuning the SVCp-dp / dt value, extending by 30 seconds for every 0.01 mmHg / s increase); if RAP-dp / dt < 0.02 mmHg / s, then the occlusion time is set to 6 minutes. Specifically: During the occlusion process, it is determined whether SVCp≤30mmHg is met; if not, the occlusion is stopped immediately; During the occlusion process, the SVCp rise rate is monitored in real time: if SVCp-dp / dt>0.08mmHg / s, the occlusion is stopped immediately and venting is initiated; otherwise, the occlusion state is maintained until the occlusion time ends and venting is initiated.

[0032] When initiating emptying, with the first balloon 10 partially inflated but not completely collapsed, the first blood pressure sensor monitors the superior vena cava pressure (SVCp) and the second blood pressure sensor monitors the right atrial pressure (RAP). The pressure gradient ΔP between the superior vena cava and the right atrium (ΔP = SVCp - RAP) is calculated to determine the emptying duration. Specifically: if ΔP drops to 3-5 mmHg, emptying is immediately stopped, maintaining the current inflation level of the first balloon 10; if ΔP does not drop to 3-5 mmHg, the rate of ΔP decrease is assessed: if the rate of ΔP decrease is < 0.01 mmHg / s, emptying is stopped after 60 seconds; otherwise, emptying is stopped 5 seconds earlier. During the venting process, ΔP is continuously monitored.

[0033] In addition, dual indicators are used to control the termination of treatment: Determine if the actual treatment duration is greater than or equal to the minimum treatment duration: If not, continue the occlusion cycle, updating the monitoring data via the first and second blood pressure sensors after each occlusion cycle; if yes, calculate ΔP-stab for three consecutive occlusion cycles and determine if it is ≤15%; if not, continue the occlusion cycle; if yes, check if RAP ≤8 mmHg and ΔP ≤5 mmHg at the end of the occlusion period for two consecutive occlusion cycles: if yes, terminate treatment; if not, determine if there are five consecutive occlusion cycles where RAP-dp / dt <0.01 mmHg / s: if there are, terminate treatment; otherwise, extend treatment for two more occlusion cycles and return to determine the actual treatment duration. Specifically: After treatment is terminated, the first balloon 10 is inflated to 30% and maintained for 30 minutes. If the fluctuation of RAP and ΔP is monitored to be ≤2 mmHg, the first balloon 10 is completely deflated.

[0034] The working principle and process of this invention will be explained in detail below with an example.

[0035] refer to Figure 4 and Figure 5 A portion of the balloon catheter device 100 (the first balloon 10, the second balloon 20, and a portion of the six-lumen catheter 30) is located inside the patient, while the other portion and the control processor 300 are located outside the patient. Specifically, refer to... Figure 3 and Figure 5The balloon catheter device 100 is inserted into the superior vena cava (SVC) of a heart failure patient through a specific location (such as the jugular vein). The first balloon 10 is placed proximal to the SVC, 1-2 cm from the junction of the SVC and the right atrium (RA). The second balloon 20 is placed within the pulmonary artery (PA) and automatically floats to the target location via blood flow guidance. The first balloon 10 is used to periodically obstruct the SVC, reducing venous return by approximately 30% and lowering right atrial pressure and pulmonary capillary wedge pressure. The second balloon 20 is used to assist a third blood pressure sensor in monitoring pulmonary artery pressure and assessing the impact of SVC obstruction on the right ventricle.

[0036] The interventional procedure is achieved using a guidewire and a tearable sheath. During the procedure, the second balloon 20 remains collapsed and is advanced through the sheath to the right atrium and then to the pulmonary artery, with the pressure waveform from the third blood pressure sensor confirming whether it has reached its destination. Simultaneously, the first balloon 10 also remains collapsed and is advanced to the proximal end of the superior vena cava (SVC), ensuring that the center of the first balloon 10 is positioned above the junction of the SVC and the right atrium (RA). Next, a certain amount of gas is injected into the second balloon 20, causing it to automatically float to the target position. Once the target position is reached, the gas in the second balloon 20 is withdrawn, keeping it collapsed. Here, the gas drive module 3002 inflates and deflates the second balloon 20 through the gas delivery tube 80 and the gas delivery chamber 35. Figure 3 The RV shown represents the right ventricle.

[0037] Therefore, the first blood pressure sensor monitors the superior vena cava pressure signal, the second blood pressure sensor monitors the right atrial pressure signal, and the third blood pressure sensor monitors the pulmonary artery pressure signal, and feeds the signals back to the blood pressure signal acquisition module 3005. The cardiac output signal monitored by the thermistor is fed back to the electrical signal acquisition module 3004. The liquid drive module 3003 performs liquid filling and emptying operations on the first balloon 10 through the infusion tube 70 and the infusion chamber 34, and performs periodic occlusion and emptying operations on the first balloon 10.

[0038] In clinical practice, when heart failure patients experience elevated blood pressure in the right atrial rhabdomyocardium (RA), the pressure gradient between the superior vena cava (SVC) and the right atrial RA decreases, significantly slowing blood flow velocity and disrupting normal periodic fluctuations. Obstructed venous return leads to proximal dilation of the inferior vena cava (IVC), with weakened pulsation amplitude with respiration. Hepatic venous blood flow exhibits "ex-hepatic flow," indicating that right ventricular dysfunction has affected hepatic circulation. Since right atrial RA blood pressure in heart failure patients typically rises to 12-25 mmHg, lowering right atrial blood pressure is crucial to alleviate cerebral and lower limb blood flow. In light of this, this invention employs artificial obstruction of superior vena cava SVC blood flow to reduce right atrial RA preload and reconstruct an effective pressure gradient, thereby promoting diuresis and relieving congestion.

[0039] In practice, based on individual patient hemodynamic differences, the control processor 300 performs adaptive occlusion-emptying cycles on the first balloon 10 using monitoring data from the first and second blood pressure sensors, a strategy drastically different from existing fixed-duration occlusion and emptying strategies. Meanwhile, the pulmonary artery pressure signal monitored by the third blood pressure sensor and the cardiac output signal monitored by the thermistor are used to reflect the effectiveness of the treatment.

[0040] The first balloon 10 occlusion-emptying cycle procedure is as follows: Step S1: Initiate occlusion. Inflate (bulge) the first balloon 10 and gradually occlude the superior vena cava. Simultaneously, activate the first blood pressure sensor to monitor the superior vena cava pressure (SVCp) and the second blood pressure sensor to monitor the right atrial pressure (RAP), with a sampling frequency of, for example, 10 Hz.

[0041] Step S2: Calculate the rate of pressure change. In the first 120 seconds after superior vena cava occlusion, based on the pressure data collected in step S1, calculate the rate of decrease of right atrial pressure (RAP-dp / dt) and the rate of increase of superior vena cava pressure (SVCp-dp / dt), where: RAP-dp / dt is the change in RAP per unit time, reflecting the efficiency of right ventricular load relief, and SVCp-dp / dt is the change in SVCp per unit time.

[0042] Step S3: Determine the occlusion duration. The occlusion duration is determined based on the pressure change rate calculated in Step S2. Specifically: if RAP-dp / dt ≥ 0.05 mmHg / s and SVCp-dp / dt ≤ 0.03 mmHg / s (high-efficiency relief type, patient is sensitive to occlusion response, excessive occlusion should be avoided), then the occlusion duration is set to 3 minutes; if 0.02 mmHg / s ≤ RAP-dp / dt < 0.05 mmHg / s (standard relief type), then the occlusion duration is set to 4-5 minutes, with the specific duration fine-tuned according to the SVCp-dp / dt value, i.e., extending by 30 seconds for every 0.01 mmHg / s increase; if RAP-dp / dt < 0.02 mmHg / s (low-efficiency relief type, patient has a poor occlusion response), then the occlusion duration is set to 6 minutes. Specifically: During the occlusion process, it is determined whether SVCp ≤ 30 mmHg is met. If not, the occlusion is stopped immediately. During the occlusion process, the rate of increase of SVCp is monitored in real time: if SVCp-dp / dt > 0.08 mmHg / s (risk of acute congestion), the occlusion is stopped immediately and the process proceeds to step S4 to start purging; otherwise, the occlusion state is maintained until the occlusion time set in step S3 ends and the process proceeds to step S4.

[0043] Step S4: Initiate emptying. Gradually inflate the first balloon 10 (keeping it partially inflated to avoid complete collapse), while simultaneously activating the first blood pressure sensor to monitor superior vena cava pressure (SVCp) and the second blood pressure sensor to monitor right atrial pressure (RAP). The sampling frequency is, for example, 10Hz. Calculate the pressure gradient ΔP between the superior vena cava and the right atrium, where ΔP = SVCp - RAP.

[0044] Step S5: Determine the emptying duration. Based on the pressure gradient ΔP calculated in step S4, determine whether emptying should stop: if ΔP drops to 3mmHg-5mmHg (the physiological pressure gradient is extremely unreasonable), then immediately stop emptying and maintain the current inflation level of the first balloon 10; if ΔP does not drop to 3mmHg-5mmHg, then further determine the rate of ΔP descent.

[0045] Step S6: If the rate of decrease of ΔP is <0.01 mmHg / s (slow emptying), stop emptying after 60 seconds; if the rate of decrease of ΔP is ≥0.01 mmHg / s (rapid recovery of blood flow), stop emptying 5 seconds earlier to reduce circulatory impact; during the emptying process, return to step S4 to continuously monitor ΔP.

[0046] Step S7: After the evacuation stops, determine whether the treatment termination conditions are met: if the actual treatment time is ≥ the minimum treatment time set by the operator and the cumulative pressure gradient stability ΔP-stab of 3 consecutive occlusion cycles is ≤15%, then terminate the treatment process; otherwise, return to step S1 and enter the next occlusion cycle.

[0047] Here, a blocking process and a venting process constitute a blocking cycle.

[0048] Furthermore, in practice, this invention employs two parameters—the minimum treatment duration set by the surgeon and the cumulative pressure gradient stability (ΔP-stab)—to determine the timing of termination of the entire treatment, thereby forming a dual-indicator control with the aforementioned occlusion cycle.

[0049] The minimum treatment duration set by the surgeon refers to the shortest possible treatment time preset by the doctor based on the patient's underlying condition, ensuring the intensity of basic treatment and avoiding premature termination. The minimum treatment duration is generally set between 6 and 48 hours, depending on the condition.

[0050] Cumulative pressure gradient stability (ΔP-stab) refers to the coefficient of variation (CV) of the difference between SVCp and RAP (ΔP) over multiple consecutive occlusion cycles. If ΔP-stab ≤ 15%, it indicates that the hemodynamic state tends to be stable, and vice versa.

[0051] The calculation process for ΔP-stab is as follows: calculate ΔP for each blocking cycle, and then calculate the average value ΔP for all ΔP values. aveAnd the standard deviation SD is calculated. Then the coefficient of variation CV is calculated based on the following formula: ΔP-stab=(SD / ΔP ave )×100%.

[0052] The treatment duration control process is as follows: Step 1: Start treatment, timing module 3006 starts timing, and the monitoring of the first blood pressure sensor and the second blood pressure sensor is started simultaneously; Step 2: Determine the actual treatment duration (T) actual Is it greater than or equal to the minimum treatment duration (T)? min If not, continue the occlusion cycle (occlusion-emptying cycle). After each occlusion cycle is completed, update the monitoring data through the first blood pressure sensor and the second blood pressure sensor and return to step 2; if yes, proceed to step 3. Step 3: Calculate ΔP-stab for three consecutive blocking cycles and determine if it is ≤15%; if not, continue blocking cycles; if so, proceed to Step 4. Step 4: Check if the following conditions are met: "RAP ≤ 8 mmHg (return to normal range) and ΔP ≤ 5 mmHg at the end of the occlusion period in two consecutive occlusion cycles": If yes, terminate treatment and proceed to step 6; if no, proceed to step 5. Step 5: Determine if there is a "RAP-dp / dt < 0.01 mmHg / s for 5 consecutive occlusion cycles (treatment ineffective)": If so, terminate treatment and proceed to Step 6; if not, extend treatment for 2 more occlusion cycles, and return to Step 2 after completion. Step 6: After treatment is terminated, inflate the first balloon 10 to 30% and maintain it for 30 minutes. If the fluctuation of RAP and ΔP is monitored to be ≤2 mmHg, then inflate the first balloon 10 completely.

[0053] Throughout the entire treatment process, pulmonary artery pressure and cardiac output are used to reflect the effectiveness of the treatment.

[0054] Pulmonary artery pressure directly reflects the right heart pumping resistance. If it gradually approaches the normal range (e.g., systolic blood pressure 15 mmHg ~ 30 mmHg), it indicates that the occlusion cycle control parameters of the first balloon 10 are suitable for the patient's condition and the treatment is effective. If it continues to rise or fall, it suggests that the current occlusion strategy needs to be adjusted to avoid adjustment deviations caused by relying solely on SVCp and RAP parameters.

[0055] Cardiac output reflects the heart's pumping function, and one of the treatment goals for patients with ADHF is to restore normal cardiac output (the normal range for adults is 3.5 L / min to 5.5 L / min). During treatment, if cardiac output gradually increases and stabilizes within the normal range, it indicates that the occlusion strategy has effectively reduced cardiac preload and improved right ventricular function. If cardiac output remains low (e.g., <3.0 L / min), it suggests that the treatment has not achieved the expected results, and the occlusion strategy needs to be adjusted in conjunction with parameters such as RAP and ΔP, or a "no response warning" may be triggered.

[0056] The advantages of this invention are: 1. This invention monitors superior vena cava pressure using a first blood pressure sensor and right atrial pressure using a second blood pressure sensor. Therefore, on the one hand, based on the monitoring of superior vena cava and right atrial pressure, the first balloon allows for reasonable control of occlusion and emptying time. The occlusion status of the superior vena cava can be adjusted in real time according to the individual patient's hemodynamic characteristics. On the other hand, it can be used to effectively control treatment duration, avoiding premature termination leading to insufficient treatment and overtreatment increasing the risk of complications. This meets the treatment needs of various types of patients, such as those sensitive to occlusion and those with slow occlusion response, avoids increasing the risk of vascular damage, and significantly improves treatment efficacy.

[0057] 2. This invention effectively reflects the treatment effect by monitoring pulmonary artery pressure through a third blood pressure sensor, avoiding adjustment deviations caused by relying solely on superior vena cava pressure and right atrial pressure parameters. The combination of cardiac output and pulmonary artery pressure monitoring significantly enhances the monitoring of treatment effectiveness. Furthermore, the waveform of pulmonary artery pressure monitored by the third blood pressure sensor allows the second balloon to quickly and accurately reach the pulmonary artery.

[0058] 3. The present invention is highly operable, significantly shortens the treatment time, improves the treatment effect, and is easy to promote in clinical practice.

[0059] The above description describes the preferred embodiments of the present invention and the technical principles applied thereto. For those skilled in the art, any obvious changes such as equivalent transformations or simple substitutions based on the technical solutions of the present invention, without departing from the spirit and scope of the present invention, shall fall within the protection scope of the present invention.

Claims

1. A vena cava occlusion ventricular assist system, characterized in that, The device includes a balloon catheter assembly and a control processor connected to the balloon catheter assembly. The balloon catheter assembly includes a six-lumen catheter with a first balloon in the middle, which is used to occlude the superior vena cava by placing it 1-2 cm from the junction of the superior vena cava and the right atrium. A second balloon is located near the proximal end of the six-lumen catheter and is used to place it into the pulmonary artery. The six-lumen catheter has a first pressure chamber, a second pressure chamber, a third pressure chamber, an infusion chamber, a gas infusion chamber, and a cardiac monitoring chamber that are not interconnected. The first pressure chamber proximal port is positioned as the first pressure measuring port near the distal end of the first balloon, and the superior vena cava pressure is monitored by a first blood pressure sensor; the second pressure chamber proximal port is positioned as the second pressure measuring port near the proximal end of the first balloon, and the right atrial pressure is monitored by a second blood pressure sensor; the third pressure chamber proximal port is positioned as the third pressure measuring port near the proximal end of the six-lumen catheter, and the pulmonary artery pressure is monitored by a third blood pressure sensor; the infusion chamber proximal port is positioned as the infusion port inside the first balloon, and is used to inflate or deflate the first balloon. The near port of the gas delivery chamber is located inside the second balloon as a gas delivery port and is used to inflate and deflate the second balloon; the near port of the cardiac monitoring chamber is located near the distal end of the second balloon as a monitoring port, and cardiac output is monitored by a thermistor placed at the monitoring port; the distal ports of the first pressure chamber, the second pressure chamber, the third pressure chamber, the infusion chamber, the gas delivery chamber and the cardiac monitoring chamber are connected to a pipeline.

2. The vena cava occlusion ventricular assist system as described in claim 1, characterized in that, The first pressure chamber, the second pressure chamber, the third pressure chamber, the infusion chamber, the gas infusion chamber, and the distal port of the cardiac monitoring chamber are located at the distal end of the six-lumen catheter. An injection head is installed at the distal end of the six-lumen catheter, and the tubing is connected to the injection head.

3. The vena cava occlusion ventricular assist system as described in claim 2, characterized in that, The pipeline includes a first pressure measuring tube, a second pressure measuring tube, a third pressure measuring tube, an infusion tube, a gas infusion tube, and a cardiac monitoring tube. The first pressure measuring tube, the second pressure measuring tube, the third pressure measuring tube, the infusion tube, the gas infusion tube, and the cardiac monitoring tube are respectively connected to the first pressure chamber, the second pressure chamber, the third pressure chamber, the infusion chamber, the gas infusion chamber, and the cardiac monitoring chamber via the injection head. The thermistor cable is led out through the cardiac monitoring chamber and the cardiac monitoring tube, which are filled with physiological saline.

4. The vena cava occlusion ventricular assist system as described in claim 1, characterized in that, The diameters of the first pressure measuring port, the second pressure measuring port, and the third pressure measuring port are between 0.8 mm and 1.2 mm.

5. The vena cava occlusion ventricular assist system as described in claim 1, characterized in that, The first balloon is sealed to the surface of the six-lumen catheter to prevent the liquid inside the first balloon from leaking out; the second balloon is sealed to the surface of the six-lumen catheter to prevent the gas inside the second balloon from leaking out.

6. The vena cava occlusion ventricular assist system as described in claim 1, characterized in that, The diameter of the monitoring port is between 0.5mm and 1.0mm, and the thermistor is equipped with an encapsulation cover.

7. The vena cava occlusion ventricular assist system as described in claim 1, characterized in that, The control processor includes a housing, within which are a processing module, a gas drive module, an electrical signal acquisition module, a blood pressure signal acquisition module, and a timing module. Outside the housing is a liquid drive module. The processing module is electrically connected to the gas drive module, the electrical signal acquisition module, the blood pressure signal acquisition module, the liquid drive module, and the timing module. The gas delivery tube is connected to the gas drive module via a gas delivery extension tube, and the infusion tube is connected to the liquid drive module via an infusion extension tube. The electrical signal acquisition module is connected to the thermistor via a cable extending from the balloon catheter device. The blood pressure signal acquisition module is connected to the pressure measuring chips of the first blood pressure sensor, the second blood pressure sensor, and the third blood pressure sensor.

8. The vena cava occlusion ventricular assist system as described in any one of claims 1 to 7, characterized in that, During the occlusion of the superior vena cava by the first balloon, based on the superior vena cava pressure monitored by the first blood pressure sensor and the right atrial pressure monitored by the second blood pressure sensor, the occlusion duration is determined by calculating the rate of decrease of right atrial pressure and the rate of increase of superior vena cava pressure within the first 120 seconds after the superior vena cava occlusion. Specifically: if the rate of decrease of right atrial pressure is ≥0.05 mmHg / s and the rate of increase of superior vena cava pressure is ≤0.03 mmHg / s, the occlusion duration is set to 3 minutes; if 0.02 mmHg / s ≤ the rate of decrease of right atrial pressure < 0.05 mmHg / s, the occlusion duration is set to 4-5 minutes; if the rate of decrease of right atrial pressure is <0.02 mmHg / s, the occlusion duration is set to 6 minutes. During the occlusion process: determine whether the superior vena cava pressure is ≤30 mmHg; if not, stop the occlusion immediately; monitor the rate of increase of superior vena cava pressure: if the rate of increase of superior vena cava pressure is >0.08 mmHg / s, stop the occlusion immediately and initiate drainage; otherwise, maintain the occlusion state until the occlusion time ends and initiate drainage.

9. The vena cava occlusion ventricular assist system as described in claim 8, characterized in that, The initiation of air evacuation includes: with the first balloon partially inflated but not completely collapsed, activating the first blood pressure sensor to monitor the superior vena cava pressure and the second blood pressure sensor to monitor the right atrial pressure, calculating the pressure gradient between the superior vena cava and the right atrial region to determine the air evacuation duration, wherein: if the pressure gradient drops to 3mmHg-5mmHg, air evacuation is immediately stopped, maintaining the current inflation level of the first balloon; if the pressure gradient does not drop to 3mmHg-5mmHg, the rate of pressure gradient descent is determined: if the rate of pressure gradient descent is <0.01mmHg / s, air evacuation is stopped after 60 seconds; otherwise, air evacuation is stopped 5 seconds earlier; During the venting process, the pressure gradient is continuously monitored.

10. The vena cava occlusion ventricular assist system as described in claim 9, characterized in that, This also includes using dual-indicator control for treatment termination: Determine if the actual treatment duration is greater than or equal to the minimum treatment duration: If not, continue the occlusion cycle, updating the monitoring data through the first and second blood pressure sensors after each occlusion cycle is completed; If yes, calculate the cumulative pressure gradient stability of three consecutive occlusion cycles and determine if it is ≤15%; If no, continue the occlusion cycle; If yes, check if the right atrial pressure at the end of the occlusion period in two consecutive occlusion cycles is ≤8 mmHg and the pressure gradient is ≤5 mmHg; If yes, terminate the treatment, otherwise determine if there is a right atrial pressure decrease rate <0.01 mmHg / s in five consecutive occlusion cycles; If yes, terminate the treatment, otherwise extend the treatment for two more occlusion cycles and repeat the process. Specifically: after treatment is terminated, the first balloon is inflated to 30% and maintained for 30 minutes. If the fluctuation of right atrial pressure and pressure gradient is monitored to be ≤2 mmHg, the first balloon is completely deflated.

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