Personalized surgical repair of left ventricular aneurysm with computer-assisted ventricular engineering

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1 Interactive CardioVascular and Thoracic Surgery 19 (2014) doi: /icvts/ivu219 Advance Access publication 21 August 2014 ORIGINAL ARTICLE ADULTCARDIAC Personalized surgical repair of left ventricular aneurysm with computer-assisted ventricular engineering István Hartyánszky a, *, Attila Tóth a, Balázs Berta a, Miklós Pólos a, Gábor Veres a, Béla Merkely a, Zoltán Szabolcs a and John Pepper b a b Semmelweis University Heart and Vascular Center, Budapest, Hungary Royal Brompton Hospital, London, UK * Corresponding author. Semmelweis University Heart and Vascular Center, Hermina u 73B, 1162 Budapest, Hungary. Tel: ; drharist@gmail. com (I. Hartyánszky). Received 16 September 2013; received in revised form 25 March 2014; accepted 13 April 2014 Abstract OBJECTIVES: Although circular ventricular resection techniques are the gold standard of left ventricular (LV) restoration, these techniques can lead to suboptimal results. Postoperative systolic resection can be inadequate, because it must be planned on a heart stopped in diastole. Low cardiac output due to insufficient LV volume results in a potentially unstable condition, and cannot be corrected. Our aim was to find a preoperative method to minimize risk and maximize outcome with ventricular restoration. METHODS: We created a novel method combining surgery with gadolinium-enhanced magnetic resonance to construct a preoperative 3D systolic heart model. The model was utilized to determine resection points that could be intraoperatively used. According to our calculations with the predetermined resection line, the calculated percentage reduction in LV volume was above 30%, and LV volumes were predicted above normal values; thus, performing the operation using these resection points is likely to be safe and effective. We had a mixed, real-life patient group: mitral insufficiency or pulmonary hypertension were not exclusion criteria. RESULTS: Forty-one procedures (12 concomitant mitral valve plasty) were done on consecutive patients in a single-centre experience. The incidence rate of major adverse clinical events was 32% postoperatively (n = 13). Control MRI showed a significant improvement in ejection fraction (18.3 ± 4.3 vs 31.3 ± 3.3; P = 0.04). All patients improved their New York Heart Association (NYHA) class postoperatively (40 patients NYHA III/IV versus 40 NYHA I/II). During long-term follow-up, 1 patient died due to end-stage heart failure. CONCLUSIONS: Using this model, we were able to find the optimal resection line providing an excellent postoperative result, thus minimizing the risk of low cardiac output syndrome. Keywords: Surgical restoration of left ventricle Left ventricular geometry Ischaemic heart disease INTRODUCTION The number of patients with end-stage heart failure due to ischaemic heart disease continues to increase annually. Nowadays, heart transplantation is the best therapeutic option with good long-term results. However, owing to the scarcity of donor organs, alternative therapies are needed [1]. One of these could be the surgical reconstruction of a dilated left ventricle, although this procedure may carry the risk of significant complications. Difficulties such as inaccurate delineation of the transmural necrosis of the myocardium or immature aneurysms can lead to suboptimal postoperative left ventricular (LV) geometry and volume [2]. Furthermore, intraoperative planning of the LV resection lines could elongate cardiopulmonary bypass time, thus increasing mortality and morbidity [3]. Moreover, these operations are currently performed intuitively and without a comprehensive quantitative analysis and planning that would make clinical success significantly more predictable. The aim of our study was to use modern imaging techniques, computational models and surgery to create a new combined approach to minimizing these problems. With our tool, the surgeon would be able to asses prospectively individual patient risk and subsequently propose and plan a personalized surgical procedure resulting in best possible restoration of cardiac function. Therefore, project aims to improve the success of a complex cardiac surgical procedure, which has until now largely depended on the experience of the individual surgeon. METHODS Patients ORIGINAL ARTICLE Presented at the 27th Annual Meeting of the European Association for Cardio- Thoracic Surgery, Vienna, Austria, 5 9 October Fifty patients underwent a surgical eligibility evaluation using a computer-assisted ventricular engineering (CAVE) procedure at The Author Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

2 802 I. Hartyánszky et al. / Interactive CardioVascular and Thoracic Surgery Semmelweis University Heart and Vascular Center between 2009 and Surgical ventricular restoration was done in 41 cases. The average age was 68.8 years; there were 14 female and 27 male patients. We had a mixed, real-life patient group: mitral insufficiency or pulmonary hypertension were not exclusion criteria. The functional class of heart failure patients was assessed according to New York Heart Association (NYHA) preoperatively and at follow-up (on average 26 ± 6 months postoperatively). Data for major adverse clinical events (bleeding, myocardial infarction, arrhythmia, low cardiac output syndrome, infection, renal dysfunction and neurological deficit) were collected up to 30 days postoperatively. The study was approved by the Local Ethical Board under the number 202/2005. Computer-assisted preoperative planning and left ventricular reconstruction simulation Fifty patients underwent preoperative cardiac MR imaging and volume segmentation and, based on this information, a virtual resection was simulated. The MR imaging procedures were performed using a General Electric 1.5-T Signa Infinity magnet equipped with EchoSpeed gradients (gradient strength: 33 mt/m, slew rate: 120 mt/m/ms), running LX 9.1 software. After acquiring transverse FIESTA movies, multiple, double-oblique FIESTA scout images were collected in various orientations (including the horizontal and vertical long axis). Long-axis Table 1: Cardiac magnetic resonance imaging parameters used for preoperative planning Imaging parameters FIESTA Late enhancement images TR (ms) TE (ms) Flip angle ( ) Matrix Bandwidth (khz) NEX 1 2 Views per segment TR: repetition time; TE: echo time; NEX: number of excitations. (two-chamber, four-chamber and left ventricular outflow tract) and a stack of short-axis movies were subsequently acquired. From 10 to 20 min after administration of gadolinium contrast material followed by a saline flush (0.1 mmol/tskg MultiHance, or 0.15 mmol/ tskg OmniScan) using a Medrad double-barrel power injector, late enhancement images (segmented gradient-echo sequence) were collected in long- and short-axis orientations. The inversion time was individually set to null the normal myocardium. The slice thickness was 8 mm; short-axis images were acquired without an interslice gap. For additional imaging parameters, see Table 1. All images were taken in the end-expiratory position, monitored by a pneumatic respiratory belt. The evaluation of the MR data was done after network transfer on a separate machine using the MASS (Medis, Netherlands) software (Linux version) running on a General Electric Advantage Workstation. The transmurality threshold of 50% was taken as the limit when determining the viability of each segment. Three-dimensional planning was performed on a General Electric Advantage Workstation. Measurements were made in systole (determined individually), usually at 30 40% of the RR interval. For estimation of the post-surgical volume, the left chamber was dissected by a scalpel tool at the proposed site of the surgical repair of the ventricle. Measurement of the corresponding volume was performed after removing all other structures of the thorax except the left ventricle. Before the volume measurement, a threshold limit depending on the individual contrast enhancement ( 150 HU) was applied to the volume. The difference between the volumes before and after the scalpel tool dissection was used to estimate the effect of the surgery on the LV end-systolic volumes. The incision lines (resection points) could then be labelled as seen in Fig. 1. For surgical planning, double-oblique slices were prepared in horizontal and vertical long-axis views, after removing all other structures of the thorax except the left ventricle. Two resection points were determined in both oblique planes, and the distances between these four resection points and the LV apex were measured. Using these resection points, the virtual aneurysmectomy and the virtual circular reduction of the left ventricle were performed. Finally, we measured two oblique diameters of the implantable patch. After the virtual reduction of the ventricular end-systolic volumes were measured, LV stroke volume indexes were calculated and compared with normal values [4]. If the calculated reduction of the left ventricle was above 30%, surgery was predicted to be effective. If the calculated LV stroke volume index was above the normal range, surgery was predicted to be safe. If both conditions were fulfilled, then surgical ventricular restoration was performed. The Figure 1: Virtual ventricular restoration using gadolinium-enhanced cardiac MR data. Measuring of the implantable patch on the preoperative model: BC to AD length ratio should be 1 : 3. The angle between EB and AB, or FC and DC, should be 45. BC length determines the antero-posterior diameter of the implantable patch (21.7 mm). A: anterior; P: posterior; S: septal; L: lateral resection point; X: apex reference point.

3 I. Hartyánszky et al. / Interactive CardioVascular and Thoracic Surgery 803 whole planning procedure and preoperative decision-making were performed by the radiologist and the cardiac surgeon together. Long-term follow-up was done in all patients by relying on a control cardiac MR scan. Pre- and postoperative ejection fractions measured by cardiac MR were compared to evaluate LV function and geometry. Surgical technique The surgery was performed with standard extracorporeal circulation in moderate hypothermia. Ante- and retrograde cold crystalloid cardioplegia were performed every 20 min, and controlled aortic root reperfusion with warm blood cardioplegia prior to cross-clamp release was used. Intraoperatively, the predetermined resection points were identified using linear measurements from the reference point at the apex. These points were connected by a running 2-0 TiCrone tobacco-pouch suture. After circular reduction of the left ventricle, a patch was made from Haemapatch using the preoperatively calculated diameters and sutured with a running 4-0 Prolene stitch (Fig. 2). The remnant of the LV aneurysm was then sutured over the patch with running 0 TiCrone to minimize postoperative bleeding. Bypass was discontinued routinely followed by a customary closure. Statistical analysis To evaluate the statistical difference between pre- and postoperative ejection fractions, paired t-tests were performed (significant if P 0.05). For long-term survival analysis, Kaplan Meier curves were calculated. RESULTS Fifty consecutive patients referred for surgical ventricular restoration underwent the CAVE procedure. In 41 patients, ventricular restoration was predicted to be safe and effective, and surgery was performed. In 12 of these cases, concomitant mitral valve plasty was done; in 40 of these cases, coronary artery bypass graft operation was done, with an average of 2.2 grafts. In nine cases, either the predicted LV stroke volume index was below the normal range, or the predicted reduction of the ventricle was less than 30%; thus, surgical ventricular restoration was not suggested. Six of these nine patients had coronary artery bypass grafting alone, and three were not operated on. There was no mortality perioperatively, and or during the short postoperative period (30 days). The incidence rate of major adverse clinical events (bleeding, myocardial infarction, arrhythmia, Table 2: Major adverse clinical events in the short postoperative period after surgical ventricular restoration in patients with computer-assisted ventricular engineering Major adverse clinical events Bleeding 4 Renal dysfunction 3 Infection 3 Low cardiac output syndrome 1 Severe neurological dysfunction 1 Ventricular arrhythmia 1 Number ORIGINAL ARTICLE Figure 2: MR-based ventricular reconstruction. (A) Resection points determined by wall thickness changes in systole, radiological signs of active muscle contraction and comparison of the MR pictures for viability. (B) Measured distances between the resection points and the apex can be seen on the anteroposterior oblique plane. A: anterior; P: posterior; S: septal; L: lateral resection point. (C) Resection of the aneurysm. (D) Suturing of the patch.

4 804 I. Hartyánszky et al. / Interactive CardioVascular and Thoracic Surgery low cardiac output syndrome, infection, renal dysfunction and neurological deficit) was 32% (n = 13) postoperatively (Table 2). On long-term follow-up (average follow-up time was 26 ± 6 months), we lost one patient due to end-stage heart failure (Fig. 3). A significant increase in the LV ejection fraction could be observed by comparing preoperative and control postoperative MR scan measurements using the paired t-test (31.3 ± 3.3 vs 18.3 ± 3.3%; P = 0.04). To evaluate the functional state of our patients, we collected preoperative and control NYHA classification data. All CAVE patients improved their NYHA class postoperatively (40 NYHA I/II versus 40 patients NYHA III/IV preoperatively; Table 3). DISCUSSION After many years of experience, several major key points have changed in the concept of LV aneurysm surgical treatment [5]. The use of circular resections [6] (such as the Jatene operation or Dor procedures) instead of linear resection techniques ( plication or resection) has become more popular. The circular resections feature major advantages: namely, more physiological LV shape and size resulting in decreased ventricular wall stress [7 9]. The first circular resection techniques were based on the theory of heart geometry by Hutchins and Brawley [10]. The principle of circular reconstruction of the left ventricle is to re-establish a physiological-like ventricular function and morphology closest to the one before myocardial infarction [11]. Previously, it has been shown that circular techniques have better short- and long-term results [2, 12]. Figure 3: Kaplan Meier survival curve for computer-assisted ventricular engineering (CAVE)-enhanced surgical ventricular reconstruction. Table 3: New York Heart Association (NYHA) classification data of computer-assisted ventricular engineering patients before and after surgical ventricular reconstruction (26 ± 6 months) NYHA Preoperative Postoperative I 11 II 29 III 26 IV 14 The basic concept of these is to define the separation line between the myocardium and the scar, and follow this edge with the resection line [11]. This can be challenging in the case of an immature aneurysm or when subendocardial scarring is present. The importance of the postoperative geometry and volume and its influence on long-term survival after LV restoration were proved in several studies. Isomura et al. reported an 8-year survival rate of 82.4% after 135 surgical ventricular restorations if the ventricular volume reduction was at least 33%. They had a much worse survival if they could not reach the 33% limit with volume reduction [0% survival if left ventricular end systolic volume index (LVESVI) was greater than 90 ml/m 2 ]. They emphasized the importance of precise measurements of LVESVI by MRI or scintigraphy, because echocardiography could underestimate ventricular volume due to post-ischaemic ventricular asynergy [13]. Skelley et al. found the same correlation between volume reduction ratio and survival. In their real-life patient group of 87 patients, the 5-year survival rate was 58% with LV reduction more than 30%, and only 39% with LV reduction less than 30%. They had an overall major clinical adverse event rate of 43.6% following surgery (reoperation for bleeding 6.9%, renal insufficiency 27.6%, stroke 5.7% and low cardiac output syndrome with ventricular assist device therapy in 3.4%) [14]. The patient group of Witkowski et al. was the most similar to our patient group: 79 patients with ejection fraction less than 35%, with ischaemic cardiomyopathy or anterior LV aneurysm. They performed the Dor operation in all patients. The overall mortality rate was 22% in their patient cohort [15]. We had a more favourable survival (96% at 3 years) and major clinical adverse event rate (32%) than Isomura, Skelley or Witkowski et al., but our results are not comparable due to different patient selection methods, and the different surgical techniques used in the studies. Calafiore et al. have published 20 years of experience with surgical ventricular restoration. They pointed out that it is not only volume reduction that influences the late outcome. Postoperative LV geometry also had an important role: the more conical shape gained with LV restoration, the better are the survival rates achieved [15, 16]. As shown in the literature, techniques are needed for prospective planning of ventricular reconstruction, with special emphasis on geometry and function [16 18]. However, in today s practice, patient selection, choice of surgical procedure and surgical approach are generally based on the personal experience of a particular surgeon. Over the past 10 years, several techniques have been developed to remodel or reconstruct the dilated left ventricle. The basic concept of these methods is the reduction of LV wall stress by decreasing heart size. Modern imaging techniques, such as cardiac MR or coronary CT scan, play an increasingly important role in the diagnostics for the failing heart. These new imaging techniques are now able to provide the technological background for exact modelling of LV geometry and function, leading to a personalized simulation for planning the surgical ventricular reconstruction [19]. Although the STICH trial was meant to be a milestone in ventricular reconstruction, it led to unfavourable results for surgical ventricular reconstruction [20]. In the STICH study, half of the patients underwent coronary artery bypass surgery, and the other half received coronary bypass and ventricular reconstruction. The results of the second group showed reduction in ventricular size without improvement in either LV function or clinical status. Several critical aspects have been raised against the STICH study recently. First, during such a complex operation neither patient selection nor selection of the surgical approach or the surgical

5 I. Hartyánszky et al. / Interactive CardioVascular and Thoracic Surgery 805 procedure was based on objective criteria [21]. Second, a gadolinium-enhanced MR scan was not routinely used to confirm evidence of myocardial scar tissue, to measure its area or define its location. Third, the average ventricular volume reduction was only 19% [22]. The unexpected negative results and the above limitations of the STICH trial resulted in a significant increase in scientific interest in the surgical treatment of ischaemic cardiomyopathy [23, 24]. After analysis of previous clinical and functional studies, we defined some major key points for our prospective, personalized, computer-assisted ventricular engineering technique. The first key point is the adequate patient selection. As shown in two independent studies, only patients with ventricles above a certain size benefit from ventricular reconstruction [13, 14]. Moreover, the global and regional systolic and diastolic function, as well as the synchronous contraction and relaxation of the ventricle, is of great importance [25]. The exact correlation between the ventricular volume and geometry as well as muscle function is only partially known. Therefore, we thought that the use of advanced cardiac imaging techniques such as gadolinium-enhanced cardiac MR is inevitable. The second key point is an adequate volume reduction for effective therapy. Even if a patient is considered for ventricular reconstruction solely due to volume criteria, the actual surgical reduction of ventricular size in a heart stopped in diastole is a major challenge. It has been shown that a reduction in ventricular size greater than 30% would lead to an improvement in long-term results [13, 14]. The third key point is the adequate size of the restored ventricle for safety reasons. Previously, the intuition and experience of the individual surgeon has had a crucial role, because evidence-based approaches were not available and intraoperative decision-making was based on the surgeon s experience alone. This could lead to low cardiac output syndrome, the most frequent cause of death after surgical ventricular reconstruction [5]. With our new combined approach, we were able to fulfil all the conditions we set for a prospective computer-aided decisionmaking system. First, we tried to learn from the mistakes of the STICH trial and based our decision-making on images from gadolinium-enhanced cardiac MR to have exact data on myocardial viability. We were able to facilitate a realistic personalized simulation for planning the ventricular procedure. We could standardize patient selection. With computational methods, we were able to identify those patients who would benefit from surgical ventricular reconstruction. Moreover, with prospective planning we could help intraoperative decision-making and delineate all procedural steps on the patient s three-dimensional systolic heart model. Systolic planning of the resection line made the postoperative systolic geometry and contractility more accurate and effective, making this complex procedure safer. We were able to improve LV function and patients functional state, and minimize long-term mortality. The limitations of our study are the low number of patients and the single-surgeon experience. Our plan is to make the CAVE procedure more reproducible by creating a fully automatized computer platform. Moreover, with modern telemetry, we plan to include other centres in the CAVE study. The CAVE method is applicable in nearly all cases of LV aneurysms. Furthermore, it can be effective in ischaemic cardiomyopathy, where LV restoration was previously contraindicated by the lack of a discrete edge between the myocardium and the aneurysm. Our study is the first prospective, imaging-based, clinical study of ventricular reconstruction. Funding This project was supported by the Hungarian Research Fund (OTKA K ). Conflict of interest: none declared. REFERENCES [1] Christie JD, Edwards LB, Kucheryavaya AY, Benden C, Dipchand AI, Dobbels F et al. The Registry of the International Society for Heart and Lung Transplantation: 29th adult lung and heart-lung transplant report J Heart Lung Transplant 2012;31: [2] Versteegh MI, Lamb HJ, Bax JJ, Curiel FB, van der Wall EE, de Roos A et al. MRI evaluation of left ventricular function in anterior LV aneurysms before and after surgical resection. Eur J Cardiothorac Surg 2003;23: [3] Artrip JH, Oz MC, Burkhoff D. Left ventricular volume reduction surgery for heart failure: a physiologic perspective. 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Volume reduction rate by surgical ventricular restoration determines late outcome in ischaemic cardiomyopathy. Eur J Heart Fail 2011;13: [14] Skelley NW, Allen JG, Arnaoutakis GJ, Weiss ES, Patel ND, Conte JV. The impact of volume reduction on early and long-term outcomes in surgical ventricular restoration for severe heart failure. Ann Thorac Surg 2011;91: ; discussion [15] Witkowski TG, ten Brinke EA, Delgado V, Ng AC, Bertini M, Marsan NA et al. Surgical ventricular restoration for patients with ischemic heart failure: determinants of two-year survival. Ann Thorac Surg 2011;91: [16] Calafiore AM, Iaco AL, Amata D, Castello C, Varone E, Falconieri F et al. Left ventricular surgical restoration for anteroseptal scars: volume versus shape. J Thorac Cardiovasc Surg 2010;139: [17] Di Donato M, Fantini F, Toso A, Castelvecchio S, Menicanti L, Annest L et al. Impact of surgical ventricular reconstruction on stroke volume in patients with ischemic cardiomyopathy. 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6 806 I. Hartyánszky et al. / Interactive CardioVascular and Thoracic Surgery [19] Liu Y, Wen H, Gorman RC, Pilla JJ, Gorman JH III, Buckberg G et al. Reconstruction of myocardial tissue motion and strain fields from displacement-encoded MR imaging. Am J Physiol Heart Circ Physiol 2009; 297:H [20] Jones RH, Velazquez EJ, Michler RE, Sopko G, Oh JK, O Connor CM et al. Coronary bypass surgery with or without surgical ventricular reconstruction. N Engl J Med 2009;360: [21] Buckberg GD, Athanasuleas CL. The STICH trial: misguided conclusions. J Thorac Cardiovasc Surg 2009;138: e1062. [22] Michler RE, Rouleau JL, Al-Khalidi HR, Bonow RO, Pellikka PA, Pohost GM et al. Insights from the STICH trial: change in left ventricular size after coronary artery bypass grafting with and without surgical ventricular reconstruction. J Thorac Cardiovasc Surg 2013;146: [23] Buckberg GD, Athanasuleas CL, Wechsler AS, Beyersdorf F, Conte JV, Strobeck JE. The STICH trial unravelled. Eur J Heart Fail 2010;12: [24] Dor V, Civaia F, Alexandrescu C, Sabatier M, Montiglio F. Favorable effects of left ventricular reconstruction in patients excluded from the Surgical Treatments for Ischemic Heart Failure (STICH) trial. J Thorac Cardiovasc Surg 2011;141: e [25] Tulner SA, Steendijk P, Klautz RJ, Bax JJ, Schalij MJ, van der Wall EE et al. Surgical ventricular restoration in patients with ischemic dilated cardiomyopathy: evaluation of systolic and diastolic ventricular function, wall stress, dyssynchrony, and mechanical efficiency by pressure-volume loops. J Thorac Cardiovasc Surg 2006;132: APPENDIX. CONFERENCE DISCUSSION Dr R. Dion (Genk, Belgium): All surgeons having experience in surgical ventricular restoration have encountered this terrible situation where you have at the end of the operation a perfectly contracting ventricle with spontaneous contrast and a disastrous diastolic function that you cannot improve. And on the other side, we have the STICH trial with insufficient reduction of the LV volumes and of course having less good results. Therefore, I found your approach very timely, innovative and sound, the latter in spite of the fact that I am not an imaging specialist and, therefore, that I have to believe that what you propose is reproducible, but it makes sense. It indeed makes sense to predict, before the operation, the exact systolic and diastolic behaviour of the left ventricle after surgical restoration. Of course, we use the Mannequin following the example of Lorenzo Menicanti, but my colleague, Robert Klautz from Leiden, has shown that in fact the Mannequin is more predicting the end-systolic volume than the end-diastolic volume. So it is sometimes a little bit tricky. What I like in your method is that if the reduction of the LV volume is expected to be more than 30% with a calculated LV stroke volume index staying in the normal range, surgery is definitely indicated. And by doing that, you eliminate both risks that I was mentioning at the beginning of this discussion: you are avoiding insufficient reduction, as in the STICH trial, and you re avoiding the terrible diastolic dysfunction when the stroke volume has become too small. You say that your limitation is the low number of patients. Although 41 patients is not a large number, personally I think that the fact that they have all been operated on by a single surgeon is a plus for a homogeneous development of the method. I have a few questions. First, Dr Menicanti always describes a number of patients in whom he does not need to use a patch. In my experience, I always have needed to use a patch. My first question is, using your calculations, in how many patients did you not need a patch during the ventricular restoration? The second point is that you are not addressing the sphericity index. I believe that you probably go for a better sphericity index, but you do not address that in your manuscript. And the third question has to do with mitral annuloplasty. What are the indications for mitral annuloplasty, and what is the impact of the preoperative mitral regurgitation on the indication for the whole procedure? And finally, what is the technique of your mitral valve repair? Dr Hartyanszky: First of all, regarding the patch, we always use a patch but we try to use as small a patch as possible. So usually the diameter for a patch is around 1 to 1½ cm. Dr Dion: But your method is never indicating that you do not need a patch? Dr Hartyanszky: No, no. We always use a patch. Regarding the sphericity index, yes, you are quite right, we should use that. The whole technique is based on the MRI and on the work station of the MRI. There are always two or three of us sitting in front of the monitors: one surgeon, one radiologist who is very good at computation and mathematics as well, and a cardiologist. Thus, we have personalized decision-making in every patient. That s how we always decide, so we are not using the sphericity index. Dr Dion: But you could calculate it afterwards. Dr Hartyanszky: Yes, I think we could. Dr. Dion: Sure. Dr Hartyanszky: About the mitral annuloplasty, as I ve said, this is a real-life patient group. Mitral insufficiency (or even pulmonary hypertension) is not an exclusion criteria. In all patients referred to us, we ve done all the calculations. And if the patient has a Grade IV or III mitral regurgitation, then no question, we do mitral plasty. If the patient has at least 40 mm of the largest diameter of the mitral annulus and the patient only has grade II or III, we still do the mitral valve plasty to improve long-term outcomes. And what we do is usually the restrictive ring annuloplasty using a rigid ring. Dr L. Menicanti (Milan, Italy): Do you have a matching of which is your ideal volume and which is the real volume that you achieve? Are they the same or are there some differences? Dr Hartyanszky: No, it always depends on the scar. So what we always do is just follow the scar, exclude what we have and then see what remains. If the remaining LV volume is big enough and we can cut big enough as well (more than 30% LV reduction), then we say yes for surgical LV restoration. All in all, we are not trying to reach an absolute physiological left ventricle. Dr Menicanti:So it s dependent on the anatomical situation you are facing? Dr Hartyanszky: Yes. Dr Menicanti: That s normal, okay. Dr R. Deac (Targu-Mures, Romania): Your presentation brings some objective data to what we ve done somehow subjectively. But the main point is, as you said, that you have to have a small patch, small in width because the length depends on the length of the aneurysm and the reduction in the volume. It s a very, very interesting presentation and very nicely presented. Dr H. Ozdemir (Eindhoven, Netherlands): I understood that none of your patients needed resection or ablation of the myocardium. You never discussed with the electrophysiologist? I have operated on a couple patients with endocardial ablation or endocardial resection because of a preoperative uncontrollable VT problem. Dr Hartyanszky: We had only one patient with severe VT, and we thought that we could exclude the focus but, unfortunately, it was not the case. At the end, we opted for a VT ablation. Dr M. Panagiotou (Athens, Greece): Can your method be applied also in other techniques of SVR, not only in the Dor procedure but also in some cases where the septal scar goes up to the LVAD? So you cannot do the Dor, but you should do, let s say, septoplasty with anterior plication. In this case, can your method be applied or not? Dr Hartyanszky: Very good point. It s very, very important that in all of our cases we are following the scar. So it s not a question of the technique, but it sa question of the result of our preoperative measurements. So if the scar is going high up to the septum, we always follow it, doing our calculations with these predetermined resection lines. Yes, at the end we put in a patch, so the surgical technique is always the same. But because we can make personal measurements in all different cases, we can follow the scar wherever it goes.