Method and device for assessing the effect of treatments on cardiac pressure-volume relation

Abstract

The pressure-volume relation is an important qualitative and quantitative parameter set describing functionality of vessels of a heart of a mammal like a human being. Transformation of this relation, applied to a loop in a pressure-volume plane, based on known effects of medication, provides feedback and a source for data of effects of specific methods of treatment, including, but not limited to medication; it may also include simulation of effects of surgery - though it not necessarily includes such surgery. By providing such simulation, effects of medication may be provided without actually applying a treatment, resulting in a patient not being used as a guinee pig, but being provided with the proper treatment based on results of one or more simulations of treatment, which simulations include on or more transformations of a pressure-volume loop.

Description

[0001]P136089PC00 Title: Method and device for assessing the effect of treatments on cardiac pressure-volume relation TECHNICAL FIELD The various aspects and examples thereof relate to simulation of an effect of medication on parameters affecting performance of a heart of a mammal and of a human being in particular. BACKGROUND Effect of medication on performance of a heart is only partially known, for particular performance parameters only. The actual and full effect of a person is only known after treatment with medication, which may cause discomfort with the subject that is administered the medication. US2022 / 068481 discloses a method for obtaining a physiological measure from a subject, in particular a P-V loop. The method includes obtaining a numerical model of a cardiac system and obtaining, in a non- invasive manner, physiological data. Based on the physiological data the numerical model is updated. The physiological data is then provided to this numerical model, from which a physiological measure is derived based on an output of the updated numerical model. The physiological measure includes a P-V loop. The paper "How drugs modulate the performance of the human heart" by Pierlinck e.a., published in Computational Mechanics (2022) 69:1397-1411 discloses a human-based multiscale and Multiphysics mechanistic framework that couples the effect that a drug has on one singular ion channel down at the subcellular level all the way up to a changing cardiovascular circulation at the whole body level. The developed framework provides a granular insight in malignancy of concentration- dependent drug-induced ventricular arrhythmia. The results show the clinical differences between three drug-induced arrhythmic episodes which results from the fine balance between electrophysiological action potential duration and depolarization times on the one hand and the contractile behaviour of the myocardial tissue combined with the contraction of the atria and the connection to the surrounding cardiovascular circulation on the other hand. SUMMARY It is preferred to provide more insight in effect of medication prior to administration of the medication. Therefore, a first aspect provides, in an electronic processing unit, a method of simulating an effect of a treatment on a pressure-volume loop of a heart of a mammal and a human being in particular. The method comprises obtaining non-invasively obtained image data comprising a multitude of images of the heart over time during at least one stroke of the heart, obtaining non-invasively obtain blood pressure data comprising a multitude of blood pressure values over time during at least on stroke of the heart, determining a multitude of heart volume values by determining, for each of the multitude of the images, a value of the volume of a vessel of the heart. The method further comprises construing, based on the multitude of blood pressure values and the multitude of heart volume values, a pressure-volume loop of the heart is construed and, based on the pressure-volume loop. A pressure-volume parameter set is determined that comprises at least one of the end-systolic pressure–volume relation, the end- diastolic pressure–volume relation, the arterial elastance and the end- systolic elastance. The method further comprises receiving treatment data on the treatment, retrieving, from an electronic memory, based on the treatment data, transformation data indicating an effect of the treatment on parameters comprised by the pressure-volume relation and applying a transformation data to the pressure-volume loop based on the treatment data, thus yielding a transformed pressure-volume loop. The transformed pressure-volume loop or a set of parameters derived therefrom or both are provided to an output of the electronic processing unit, for example for display on a screen in numbers or another method of visualisation. This method allows for improved determining of an effect of medication on a specific individual with his or her own specific characteristic pressure-volume characteristic. This, in turn, allows for improved determining of medication for the individual, allowing for more effective use of resources. Second, this method allows for determining potentially harmful or otherwise unwanted effects of particular medication, thus providing a technical solution in aiding a medical practitioner in setting a diagnosis and prescribing proper medication for the individual under scrutiny. An implementation of the first aspect further comprises determining a systolic time interval as a duration of the isovolumic phase with respect to the entire systolic phase and determining the end-systolic pressure–volume relation is based on the systolic time interval. The duration of the isovolumic phase may be used to determine a relation between volume and pressure for determining the end-systolic pressure- volume relationship. Another implementation further comprises, based on the transformation data, transforming the pressure-volume loop by modifying at least one first parameter of the pressure-volume parameter set and maintaining at least one second parameter of the pressure-volume parameter set. Certain medication primarily or only influences one or two parameters of the pressure-volume loop, while leaving other parameters generally unchanged. As such, particular medication may change the end systolic volume, while preserving the end-systolic pressure-volume relationship. In a further implementation, the transformation comprises moving the aortic valve closure point in the pressure-volume plane while maintaining one of the end-systolic pressure-volume relation and the arterial elastance. In this implementation, the aortic closure point is moved to a point with more volume and a higher pressure or a point with more volume and a lower pressure - in accordance with maintaining one of the end-systolic pressure-volume relation and the arterial elastance. Some medication is known to preserve the one of the end-systolic pressure-volume relation and the arterial elastance, while affecting one of the end systolic volume and arterial pressure. This implementation relates thereto. In again a further implementation, the transformation comprises modifying the end systolic volume while not modifying one of the end- systolic pressure–volume relation and the arterial elastance. Some medication affects the end systolic volume, for example because such medication results in relaxing the heart muscle, the myocardial tissue. This, in turn, results in a larger end systolic volume. Likewise, some medication results in more muscle contraction, which results in a lower end systolic volume. Yet, other relations or parameters are preserved, which is the effect simulated in this implementation. In yet another implementation, the end-diastolic volume is maintained constant. Whereas the minimal volume of the vessel, like the right ventricle, the left ventricle or either one of the atria, may be change due to more or less muscle (myocardial) work, the maximum volume resulting out of relaxation of the tissue is generally not affected. In yet a further implementation, the transformation comprises modifying the end diastolic volume while not modifying one of the end- diastolic pressure–volume relation, the end-systolic pressure–volume relation and the arterial elastance. This implementation is dedicated to particular medication. In again a further implementation, the end-systolic volume is not modified. This implementation may affect medication which results in higher aortic pressure or an end diastolic volume, yet still provides the same contraction of the myocardial tissue. In another implementation, the transformation is a linear transformation. Such transformation is relatively simple and efficient to implement. In yet another implementation, the method further comprises determining, based on the transformed pressure-volume loop, at least one of the parameters like stroke volume, stroke work, end systolic pressure, systolic blood pressure, diastolic blood pressure, end diastolic pressure and left atrial pressure. Such values provide important characteristics of functioning of the heart and therefore provide important feedback as a results of the simulation. In yet a further implementation, the vessel is the left ventricle. For most assessments of effect of medication , this is the vessel of interest, as it controls the circulation of blood in the body. In yet another implementation, the blood pressure is a brachial pressure of the mammal. The brachial pressure is relatively simple to acquire, in a non-invasive way. This allows for minimal discomfort of the mammal, like a human being, under scrutiny. In a further implementation, the image data has been obtained by means of at least one of Computer Tomography, Ultrasound echography and Magnetic Resonance Imaging. Such methods are non-invasive, which means they can be employed at less discomfort to the object under scrutiny as compared to invasive imaging methods. A second aspect provided an electronic computing device comprising an electronic data processor arranged to execute a method comprising obtaining non-invasively obtained image data comprising a multitude of images of the heart over time during at least one stroke of the heart, obtaining non-invasively obtain blood pressure data comprising a multitude of blood pressure values over time during at least on stroke of the heart, determining a multitude of heart volume values by determining, for each of the multitude of the images, a value of the volume of a vessel of the heart, construing, based on the multitude of blood pressure values and the multitude of heart volume values, a pressure-volume loop of the heart, determining a pressure-volume parameter set comprising at least one of the end-systolic pressure–volume relation, the end-diastolic pressure–volume relation. the arterial elastance, the end-systolic elastance, receiving treatment data on the treatment, the method further comprising retrieving, from an electronic memory, based on the treatment data, transformation data indicating an effect of the treatment on parameters comprised by the pressure-volume relation, applying a transformation data to the pressure- volume loop based on the treatment data, thus yielding a transformed pressure-volume loop and providing the transformed pressure-volume loop to an output of the electronic processing unit. A third aspect provides a computer programme product comprising computer executable instructions causing an electronic data processing unit, when a memory having the computer executable instructions loaded therein is operatively connected to the electronic data processing unit, execute a method comprising obtaining non-invasively obtained image data comprising a multitude of images of the heart over time during at least one stroke of the heart, obtaining non-invasively obtain blood pressure data comprising a multitude of blood pressure values over time during at least on stroke of the heart, determining a multitude of heart volume values by determining, for each of the multitude of the images, a value of the volume of a vessel of the heart, construing, based on the multitude of blood pressure values and the multitude of heart volume values, a pressure-volume loop of the heart, determining a pressure-volume parameter set comprising at least one of the end-systolic pressure–volume relation, the end-diastolic pressure–volume relation, the arterial elastance, the end-systolic elastance, receiving treatment data on the treatment, the method further comprising retrieving, from an electronic memory, based on the treatment data, transformation data indicating an effect of the treatment on parameters comprised by the pressure-volume relation, applying a transformation data to the pressure-volume loop based on the treatment data, thus yielding a transformed pressure-volume loop, providing the transformed pressure-volume loop to an output of the electronic processing unit. BRIEF DESCRIPTION OF THE DRAWINGS The various aspect and implementations thereof will now be discussed in further detail in conjunction with drawings. In the drawings, Figure 1: shows a medical imaging system; Figure 2: shows a flowchart; Figure 3: shows a left ventricle in end systolic state and end diastolic state. Figure 4: shows a pressure-volume loop based on empirical data; Figure 5 A: shows a first simulated pressure-volume loop, based on information about a first medication; and Figure 5 B: shows a second simulated pressure-volume loop, based on information about a second medication. DETAILED DESCRIPTION Figure 1 shows a medical imaging system 100. The medical imaging system 100 comprises a control device 110 for controlling the system 100. The control device 110 comprises a central processing unit 112, a storage module 114, a user interface controller 118 and an imaging controller 116. The control device 110 is, via the user interface controller 118, connected to a keyboard 152 as a user input device and to an electronic display screen 154 as a user output device. The system 100 further comprises, in this implementation as an option, a blood pressure measurement module 140 comprising a pressure cuff 142 and a control unit 144 comprising a pulse sensor 146 and a pressure control unit 148 arranged to control air pressure in the pressure cuff 142 by inflating and deflating the pressure cuff 142. The imaging controller 116 is connected to an imaging transmitter 132 and an imaging receiver 134. The imaging transmitter 132 sends out energy - electromagnetic waves like X-ray radiation, sounds waves and ultrasound waves in particular, other energy or a combination thereof - to the imaging receiver 134. The imaging transmitter 132 and the imaging receiver 134 are part of a medical imaging system 130. The medical imaging system 130 may be an MRI system, a CT system, a standard X-Ray system, an ultrasonic imaging system, another imaging system, or a combination thereof. The medical imaging system 130 is arranged to obtain imaging data of a heart 190 of a mammal, a human in particular. The imaging data preferably comprises images divided by approximately constant time intervals. The imaging data may be collected as two-dimensional or three- dimensional. In one implementation, two-dimensional data is acquired under multiple angles, which allows for reconstruction of three-dimensional image data of the heart 190. The imaging controller 116 may be arranged to process the imaging data receiver 134 to provide a two-dimensional representation, a three-dimensional reconstruction of the heart 190 or any other part of a body. The imaging controller 116 may further be arranged to provide two- dimensional cross-sections of the three-dimensional reconstruction. Additionally or alternatively, two-dimensional images as acquired are passed through to the central processing unit 112. Some or all steps may also be executed by the central processing unit 112, instead of or in conjunction with the imaging controller 116. The imaging controller and the central processing unit 112 may be included in one and the same physical entity. The central processing unit 112 comprises an edge detection subunit 122 as a wall detection unit, a volume determining subunit 124, a synchronising subunit 126 for synchronising data over time and a transforming subunit 128 for transforming graphs. The various subunits may be hardwired, programmed, in any way, including temporary, permanent, in a volatile manner, in a non-volatile manner, other, or combination thereof. The central processing unit 112 may be further arranged to execute the method according to the first aspect and methods as discussed below, with or without any option indicated and any variation thereof. In any chosen realisation, the unit eventually provides a number of positions on the image, where such positions change during time. The positions are identified by their coordinate values and represent places of interest therein. The storage module 114 is arranged to have image data stored thereon that may be acquired by means of the medical imaging system 130, as directly obtained as well as in a processed way. Furthermore, the storage module 114 may have data stored thereon as a computer programme product comprising code executable by the central processing unit 112, enabling the central processing unit to operate as discussed above. The further functionality of the system 100 and parts thereof discussed above will be further elucidated in conjunction with a flowchart 200 depicted by Figure 2. The procedure depicted by the flowchart 200 is executed by the system 100 and the electronic computing device 110 in particular, controlled by the processing unit 112. To provide this functionality, the processing unit 112 may be programmed by means of a computer programme product comprising computer executable code. The computer programme product may be stored on the storage unit 114 as an electronic memory, which may be a non-transitory memory. The various parts of the flowchart 200 are briefly summarised below. 202 start procedure 204 obtain image data over time 206 obtain pressure data over time 208 obtain volume for image 210 all done? 212 synchronise volume and pressure data over time 214 construe pressure volume loop 216 determine end-systolic pressure–volume relation; 218 determine end-diastolic pressure–volume relation 220 determine arterial elastance 222 determine end-systolic elastance 224 receive treatment data 226 retrieve transformation data 228 transform pressure volume loop 230 determine stroke volume 232 determine stroke work 234 determine end systolic pressure 236 determine systolic blood pressure 238 determine diastolic blood pressure 240 determine end diastolic pressure 242 determine left atrial pressure 244 provide determined heart parameter data 246 display heart parameter data 248 display transformed pressure-volume relation 250 end procedure 252 next image The procedure starts in a first terminator 202 and proceeds to step 204, in which image data is obtained over time, by means of the medical image system 130. Multiple images are taken from the heart 190, covering at least one heartbeat cycle. Such heartbeat cycle covers movement of the myocardial tissue of the left ventricle from the diastolic state (solid line 310 in Figure 3) to the systolic state (dashed line 320 in Figure 3). In other implementations, image data may be collected from other vessels of the heart, like the right ventricle or the atria. Preferably, at least ten or more images are taken over a heartbeat cycle, at substantially equal distances in time. In step 206, pressure data is taken over time. In this implementation, a brachial pressure is taken of the subject non-invasively using the blood pressure measurement module 140, by means of the pressure cuff 142. In another implementation, another device that may be used to determine a blood pressure of the over time, which may be the brachial pressure, aortic pressure, other, or a combination of two or more thereof. In step 208, based on the image data, volume of the left ventricle - or, in other implementations, other vessels - is determined. Firstly, the inner heart wall is determined per image acquired. This may be executed using edge detection algorithms, either using threshold algorithms, a trained neural network, another type of trained model, other, or a combination of one or more thereof. The determination of the volume of the left ventricle may be executed by calculating volume based on acquired or reconstructed three-dimensional image data. Alternatively or additionally, the volume of the left ventricle may be estimated based on a single two- dimensional image. In the latter case, the depth of the ventricle, perpendicular to the image plane, may for example be estimated as equal to the width. In step 208 is checked whether all images have been processed by detection the inner wall of a vessel - the left ventricle in this case - and whether the volume has been determined. If this is not the case, the procedure branches to step 252, in which the next image in time is selected for processing, proceeding to step 208 as above for the next image. If it is determined in step 210 that all images have been processed, the procedure continues to step 212. In step 212, pressure data acquired over time is synchronised with the determined volume data, over time. In this way, pressure-volume data points are generated. In step 214, based on the pressure-volume data points, a pressure- volume loop 410 is generated as depicted by Figure 4 in graph 400. Figure 4 shows a volume axis 402 and a pressure axis, defining, with the pressure- volume data points, the pressure-volume loop 410. From this loop, various physiologically relevant parameters may be determined. In step 216, the end-systolic pressure-volume relation 422, theESPVR is determined. The ESPVR is in this example expressed as ^^ =^^^^^^(^^ − ^^0), where ^^^^^^ is the ventricular elastance and ^^0 is the startingvolume, such parameters are estimated on the basis of the LV end-systolic pressure (^^^^^^, proportional to the brachial pressure), the end-systolic volume (^^^^^^) and timing parameters that can be extracted from the volume time curve. With these data, ^^^^^^and ^^0may be determined using: wherein the parameter ^^^^^^is computed from an empirical formula that depends on brachial pressure values and the duration of the isovolumic phase with respect to the entire systolic phase. In step 218, the end-diastolic pressure-volume relation 424, the EDPVR, is determined. The end-diastolic pressure-volume relation 424 iscommonly expressed as ^^ = ^^^^^^, where the two parameters ^^ and ^^ areestimated on the basis of relationships proposed in literature (Klotz S, Dickstein ML, Burkhoff D. A computational method of prediction of the enddiastolic pressure–volume relationship by single beat. Nature Protocols 2007; 2(9):2152-2158. DOI:10.1038 / nprot.2007.270). Further parameters can be estimated from of the end-diastolic volume (^^^^^^) and end-diastolic pressure (^^^^^^) which is estimated non- ^^ invasively using the ratio ^^′; such ratio can be measured directly from Doppler (at the mitral exit and at the mitral annulus) or can be computed directly from the volume time curve and mitral dimension using mass conservation. In step 220, the arterial elastance 426 is determined, in this example as a first approximation by the slope of the arterial end-systolic P- SV (pressure-stroke volume) relation. In step 222, the end-diastolic elastance 428 is determined, being the slope of the end-systolic pressure- volume relation 422. It is noted that also further data may be acquired or otherwise determined, based on the pressure-volume loop 410, including, but not limited to the end-systolic volume VES, the end diastolic volume VED, the stroke volume SV being the difference between the end diastolic volume VED and the end-systolic volume VES, the left ventricle end diastolic pressure A (point of closing of the mitral valve) the diastolic blood pressure B (point of opening of the atrial valve), the left ventricle end systolic pressure C (point of closing of the atrial valve), the left atrial pressure D, (point of opening of the mitral valve), other parameters or a combination of two or more thereof. In step 224, treatment data is received. Such treatment data may relate to particular medication, which is known to have a particular effect on a heart of a subject, like a human being. Such effect may be a smaller stroke volume, a larger end systolic volume, while preserving values of other parameters, like the end-diastolic pressure-volume relation 424, the end- systolic pressure-volume relation 422, arterial elastance 426 or the end- diastolic elastance 428. Further information about effect of medication on functioning of the heart 190 may be found in a paper by Ikonomidis I, Aboyans V, Blacher J, Brodmann M, Brutsaert DL, Chirinos JA, De Carlo M, Delgado V, Lancellotti P, Lekakis J, Mohty D, Nihoyannopoulos P, Parissis J, Rizzoni D, Ruschitzka F, Seferovic P, Stabile E, Tousoulis D, Vinereanu D, Vlachopoulos C, Vlastos D, Xaplanteris P, Zimlichman R, Metra M. The role of ventricular–arterial coupling in cardiac disease and heart failure: assessment, clinical implications and therapeutic interventions. A consensus document of the European Society of Cardiology Working Group on Aorta & Peripheral Vascular Diseases, European Association of Cardiovascular Imaging, and Heart Failure Association. Int J Heart Fail 2019; 21(4); 402-424. Relations between medication and effect thereof on the pressure- volume loop are stored in the storage module 114 and retrieved in step 226. Using the retrieved data, the pressure-volume loop is transformed, wherein one or more of the points defined as the left ventricle end diastolic pressure A (point of closing of the mitral valve) the diastolic blood pressure B (point of opening of the atrial valve), the left ventricle end systolic pressure C (point of closing of the atrial valve), the left atrial pressure D, (point of opening of the mitral valve) are shifted, while preserving other characteristics of the pressure-volume loop 410 as construed in step 214, based on empirical data. In this way, simulation of particular medication may be simulated. The transformation may be linear, in which implementation points in the pressure-volume loop are shifted in increased or decreased along at least one of the pressure and volume axis linearly, in dependency of a distance to a point that is shifted and a point that is not shifted. In another implementation, the transformation may be polynomial, exponential, other, or a combination of tow or more thereof. Figure 5 A shows a first example graph 500 of the simulation of a condition where the peripherical resistances are varied; solid line 512 shows the baseline as determined in step 214, a dash-dotted line 514 shows a simulation using the data retrieved in step 226. Figure 5 B shows a second example graph 550 of the simulation of a condition induced by reduction of systolic pressure and of ventricular elastance; solid line 562 shows the baseline as determined in step 214, a dash-dotted line 564 shows a simulation using the data retrieved in step 226. Based on the simulation of a particular effect of medication and in particular based on the pressure-volume loop that is a result of the simulation, an effect of the medication of further parameters may be determined, which parameters are indicators of performance of the heart 190 and the left ventricle in particular, in this example. In step 230, the stroke volume may be determined. In step 232, the stroke work may be determined, an area enclosed by the pressure- volume loop. In step 234, the end systolic pressure of the transformed loop may be determined. In step 236, the systolic blood pressure may be determined. In step 238, the diastolic blood pressure may be determined. In step 240 the end diastolic pressure may be determined. And in step 242, the left atrial pressure may be determined. Additional values of other parameters may be determined as well, based on the pressure-volume loop that is transformed based on the simulated effect of medication. In step 244, the determined heart parameter data, one or more values of parameters as determined in step 230 to step 242, are provided for evaluation and further processing of data related to the heart 190. In step 248, the parameters related to the heart 190 as indicating a simulated effect of medication, are provided for display on the electronic display screen 154. Subsequently, the procedure ends in step 250. The various aspects and implementations relate to assessment of a pressure-volume loop. The pressure-volume relation is an important qualitative and quantitative parameter set describing functionality of vessels of a heart of a mammal like a human being. Transformation of this relation, applied to a loop in a pressure-volume plane, based on known effects of medication, provides feedback and a source for data of effects of specific methods of treatment, including, but not limited to medication; it may also include simulation of effects of surgery - though it not necessarily includes such surgery. By providing such simulation, effects of medication may be provided without actually applying a treatment, resulting in a patient not being used as a guinee pig, but being provided with the proper treatment based on results of one or more simulations of treatment, which simulations include on or more transformations of a pressure-volume loop.

Claims

Claims 1. In an electronic processing unit, a method of simulating an effect of a treatment on a pressure-volume loop of a heart of a mammal, the method comprising: obtaining non-invasively obtained image data comprising a multitude of images of the heart over time during at least one stroke of the heart; obtaining non-invasively obtain blood pressure data comprising a multitude of blood pressure values over time during at least on stroke of the heart; determining a multitude of heart volume values by determining, for each of the multitude of the images, a value of the volume of a vessel of the heart; construing, based on the multitude of blood pressure values and the multitude of heart volume values, a pressure-volume loop of the heart; determining a pressure-volume parameter set comprising at least one of: the end-systolic pressure–volume relation; the end-diastolic pressure–volume relation; the arterial elastance; the end-systolic elastance; receiving treatment data on the treatment; retrieving, from an electronic memory, based on the treatment data, transformation data indicating an effect of the treatment on parameters comprised by the pressure-volume relation; applying a transformation data to the pressure-volume loop based on the treatment data, thus yielding a transformed pressure-volume loop; providing the transformed pressure-volume loop to an output of the electronic processing unit.

2. The method of claim 1, further comprising determining a systolic time interval as a duration of the isovolumic phase with respect to the entire systolic phase and determining the end-systolic pressure–volume relation is based on the systolic time interval.

3. The method of any one of the preceding claims, further comprising, based on the transformation data, transforming the pressure-volume loop by modifying at least one first parameter of the pressure-volume parameter set and maintaining at least one second parameter of the pressure-volume parameter set.

4. The method according to any one of the preceding claims, wherein the transformation comprises moving the aortic valve closure point in the pressure-volume plane while maintaining one of: the end-systolic pressure–volume relation and; the arterial elastance.

5. The method according to any of the preceding claims, wherein the transformation comprises modifying the end systolic volume while not modifying one of: the end-systolic pressure–volume relation and; the arterial elastance.

6. The method according to claim 5, wherein the end-diastolic volume is maintained constant.

7. The method according to any of claims 1 to 5, wherein the transformation comprises modifying the end diastolic volume while not modifying one of: the end-diastolic pressure–volume relation;the end-systolic pressure–volume relation and; the arterial elastance.

8. The method according to claim 7, wherein the end-systolic volume is not modified.

9. The method according to any one of the preceding claims, wherein the transformation is a linear transformation.

10. The method according to any one of the preceding claims, wherein the method further comprises determining, based on the transformed pressure-volume loop, at least one of the following parameters: stroke volume; stroke work; end systolic pressure; systolic blood pressure; diastolic blood pressure; end diastolic pressure; and left atrial pressure.

11. The method according to any of the preceding claims, wherein the vessel is the left ventricle.

12. The method according to any one of the preceding claims, wherein the blood pressure is a brachial pressure of the mammal.

13. The method according to any one of the preceding claims, wherein the image data has been obtained by means of at least one of: Computer Tomography; Ultrasound echography;Magnetic Resonance Imaging 14. Electronic computing device comprising an electronic data processor arranged to execute a method comprising: obtaining non-invasively obtained image data comprising a multitude of images of the heart over time during at least one stroke of the heart; obtaining non-invasively obtain blood pressure data comprising a multitude of blood pressure values over time during at least on stroke of the heart; determining a multitude of heart volume values by determining, for each of the multitude of the images, a value of the volume of a vessel of the heart; construing, based on the multitude of blood pressure values and the multitude of heart volume values, a pressure-volume loop of the heart; determining a pressure-volume parameter set comprising at least one of: the end-systolic pressure–volume relation; the end-diastolic pressure–volume relation; the arterial elastance; the end-systolic elastance; receiving treatment data on the treatment; retrieving, from an electronic memory, based on the treatment data, transformation data indicating an effect of the treatment on parameters comprised by the pressure-volume relation; applying a transformation data to the pressure-volume loop based on the treatment data, thus yielding a transformed pressure-volume loop; providing the transformed pressure-volume loop to an output of the electronic processing unit.

15. Computer programme product comprising computer executable instructions causing an electronic data processing unit, when a memory having the computer executable instructions loaded therein is operatively connected to the electronic data processing unit, execute a method comprising: obtaining non-invasively obtained image data comprising a multitude of images of the heart over time during at least one stroke of the heart; obtaining non-invasively obtain blood pressure data comprising a multitude of blood pressure values over time during at least on stroke of the heart; determining a multitude of heart volume values by determining, for each of the multitude of the images, a value of the volume of a vessel of the heart; construing, based on the multitude of blood pressure values and the multitude of heart volume values, a pressure-volume loop of the heart; determining a pressure-volume parameter set comprising at least one of: the end-systolic pressure–volume relation; the end-diastolic pressure–volume relation; the arterial elastance; the end-systolic elastance; receiving treatment data on the treatment; retrieving, from an electronic memory, based on the treatment data, transformation data indicating an effect of the treatment on parameters comprised by the pressure-volume relation; applying a transformation data to the pressure-volume loop based on the treatment data, thus yielding a transformed pressure-volume loop; providing the transformed pressure-volume loop to an output of the electronic processing unit.

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