Bálint Lakatos

Quantification of the relative contribution of the different right ventricular wall motion components to right ventricular ejection fraction: the ReVISION method

Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction’s ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.

Dominance of free wall radial motion in global right ventricular function of heart transplant recipients

Assessment of right ventricular (RV) function using conventional echocardiography might be inadequate as the radial motion of the RV free wall is often neglected. Our aim was to quantify the longitudinal and the radial components of RV function using three‐dimensional (3D) echocardiography in heart transplant (HTX) recipients. Fifty‐one HTX patients in stable cardiovascular condition without history of relevant rejection episode or chronic allograft vasculopathy and 30 healthy volunteers were enrolled. RV end‐diastolic (EDV) volume and total ejection fraction (TEF) were measured by 3D echocardiography. Furthermore, we quantified longitudinal (LEF) and radial ejection fraction (REF) by decomposing the motion of the RV using the ReVISION method. RV EDV did not differ between groups (HTX vs control; 96 ± 27 vs 97 ± 2 mL). In HTX patients, TEF was lower, however, tricuspid annular plane systolic excursion (TAPSE) decreased to a greater extent (TEF: 47 ± 7 vs 54 ± 4% [−13%], TAPSE: 11 ± 5 vs 21 ± 4 mm [−48%], P < .0001). In HTX patients, REF/TEF ratio was significantly higher compared to LEF/TEF (REF/TEF vs LEF/TEF: 0.58 ± 0.10 vs 0.27 ± 0.08, P < .0001), while in controls the REF/TEF and LEF/TEF ratio was similar (0.45 ± 0.07 vs 0.47 ± 0.07). Current results confirm the superiority of radial motion in determining RV function in HTX patients. Parameters incorporating the radial motion are recommended to assess RV function in HTX recipients.

A jobb kamrai anatómia és funkció korszerű echokardiográfiás vizsgálata: patológiás és fiziológiás eltérések

Accurate assessment of right ventricular geometry and function is of high clinical importance. However, several limitations have to be taken into consideration if using conventional echocardiographic parameters. Advanced echocardiographic techniques, such as speckle-tracking analysis or 3D echocardiography are reliable and simple tools providing a cost-effective and non-invasive alternative of current modalities used to characterize the right ventricle. There is a growing interest in the diagnostic and prognostic value of these methods regarding pathological (right ventricular infarction, pulmonary hypertension, arrhythmogenic right ventricular dysplasia, follow-up of heart transplantation) and even physiological (athletes heart) alterations of the right ventricle. Orv. Hetil., 2016, 157(29), 1139-1146.Accurate assessment of right ventricular geometry and function is of high clinical importance. However, several limitations have to be taken into consideration if using conventional echocardiographic parameters. Advanced echocardiographic techniques, such as speckle-tracking analysis or 3D echocardiography are reliable and simple tools providing a cost-effective and non-invasive alternative of current modalities used to characterize the right ventricle. There is a growing interest in the diagnostic and prognostic value of these methods regarding pathological (right ventricular infarction, pulmonary hypertension, arrhythmogenic right ventricular dysplasia, follow-up of heart transplantation) and even physiological (athletes heart) alterations of the right ventricle. Orv. Hetil., 2016, 157(29), 1139-1146.

Genetically determined pattern of left ventricular function in normal and hypertensive hearts

We sought to assess the inheritance of left ventricular (LV) function using speckle‐tracking echocardiography and the impact of hypertension on modifying the genetically determined pattern of contraction in a population of twins. We recruited 92 Caucasian twin pairs, including 74 hypertensive (HTN) siblings. Beyond standard echocardiographic protocol, a speckle‐tracking analysis was performed, including global longitudinal strain (GLS). Systolic function, as assessed by ejection fraction, showed moderate heritability (61%); however, GLS showed higher and dominant heritability (75%). Heterogeneity models revealed that there were no differences between the HTN and non‐HTN subjects regarding the heritability of GLS. However, the heritability estimates of diastolic function parameters, including early diastolic strain rate, were low. LV systolic biomechanics is highly heritable. GLS shows dominant heritability, despite the presence of early‐stage hypertensive heart disease. Early diastolic parameters are rather determined by environmental factors. These findings suggest the presence of a genetic framework that conserves systolic function despite the expression of diastolic dysfunction and may underlie the phenotypic progression towards heart failure with preserved ejection fraction.

Response to Ivey-Miranda and Farrero-Torres “Is there dominance of free wall radial motion in global right ventricular function in heart transplant recipients or in all heart surgery patients?”

Dear Editor, In our original article—recently published in Clinical Transplantation— we concluded that after orthotopic heart transplantation, the radial motion of right ventricular free wall compensates for the decreased longitudinal shortening to maintain ejection fraction.1 The editorial from IveyMiranda and FarreroTorres questioned whether this finding was true for all heart surgery patients. Certainly, the answer is positive. As we have discussed in our paper, there is extensive corresponding literature, and the phenomenon is very similar in cardiac surgery patients. However, the magnitude and timing of this functional shift may be different in heart transplant recipients. The aim of our study was to confirm the dominance of radial wall motion in right ventricular function in the case of heart transplant patients using a superior, 3D echocardiographic method compared to previous investigations.2 We do agree with the authors of the editorial that another, heart surgery group would have been useful. However, retrospective studies are not necessarily useful to answer every question regarding this functional remodelling. An interesting paper from Raina et al3 reported a direct comparison between heart transplant recipients (n = 54) and patients who underwent coronary artery bypass surgery (n = 23), all with preserved left and also right ventricular global function. In their twodimensional but thorough echocardiographic analysis, they found no difference between the 2 groups regarding the importance of the different right ventricular motion components. Still, if we look at the time elapsed between the operation and the echocardiogram, the difference between the heart transplant (mean 381 days) versus the coronary cohort (mean 70 days) is problematic. We have already commenced a prospective study with regular and frequent followup visits of heart transplant patients using 3D echocardiography. Moreover, the dedicated time points are the same as in the PREPAREMVR (PRediction of Early PostoperAtive Right vEntricular failure in Mitral Valve Replacement/Repair patients) study, where we are aiming to evaluate those preoperative factors that can predict early postoperative right ventricular failure or determine the functional shift seen in right ventricular function after mitral valve replacement/repair (NCT03438825). Beyond 3D echocardiography, the PREPAREMVR study includes right heart catheterization both intraoperatively and in the early postoperative period to correlate directly the results of invasive hemodynamic measurements with the advanced parameters of right ventricular function. We hope that the upcoming results of the aforementioned studies along with the comparison of these 2 cohorts will deepen our understanding of this interesting and clinically relevant topic. It is important to note that the adaptation of the right ventricle to increased afterload would imply a decrease in radial function, which bears prognostic value as well.4 However, radial function is still supernormal after heart transplantation. The selection and even more the results of the “control” population also deserve a comment. Longitudinal shortening was traditionally considered as the main determinant of global right ventricular function in healthy people; however, using the ReVISION method to compare the importance of longitudinal and radial wall motions headtohead, their relative contribution appears to be equal. A study with a larger sample size is required to confirm this, investigating different age groups and potential gender differences. In conclusion, we would like to thank the authors of the editorial for their supportive comments and more importantly, for highlighting the knowledge gap and the need for further research in the field of right ventricular function.

The Female Athlete’s Heart: Comparison of Cardiac Changes Induced by Different Types of Exercise Training Using 3D Echocardiography

We aimed to characterize female athletes heart in elite competitors in the International Federation of Bodybuilding and Fitness (IFBB) Bikini Fitness category and compare them to athletes of a more dynamic sport discipline and healthy, sedentary volunteers using 3D echocardiography. Fifteen elite female fitness athletes were recruited and compared to 15 elite, age-matched female water polo athletes and 15 age-matched healthy, nontrained controls. Using 3D echocardiography, left ventricular (LV) and right ventricular (RV) end-diastolic volume index (EDVi) and LV mass index (LVMi) were measured. Fitness athletes presented similar LV and RV EDVi compared to healthy, sedentary volunteers. Water polo athletes, however, had higher LV and also RV EDVi (fitness versus water polo versus control; LVEDVi: 76 ± 13 versus 84 ± 8 versus 73 ± 8 ml/m2, ANOVA p = 0.045; RVEDVi: 61 ± 12 versus 86 ± 14 versus 55 ± 9 ml/m2, p < 0.0001). LVMi was significantly higher in the athlete groups; the hypertrophy, however, was even more prominent in water polo athletes (78 ± 13 versus 91 ± 10 versus 57 ± 10 g/m2, p < 0.0001). To the best of our knowledge, this is the first study to characterize female athletes heart of IFBB Bikini Fitness competitors. The predominantly static exercise regime induced a mild, concentric-type LV hypertrophy, while in water polo athletes higher ventricular volumes and eccentric LV hypertrophy developed.

Exercise-induced shift in right ventricular contraction pattern: novel marker of athlete's heart?

Data about the functional adaptation of the right ventricle (RV) to intense exercise are limited. Our aim was to characterize the RV mechanical pattern in top-level athletes using three-dimensional echocardiography. A total of 60 elite water polo athletes (19 ± 4 yr, 17 ± 6 h of training/wk, 50% women and 50% men) and 40 healthy sedentary control subjects were enrolled. We measured the RV end-diastolic volume index (RVEDVi) and ejection fraction (RVEF) using dedicated software. Furthermore, we determined RV global longitudinal (RV GLS) and circumferential strain (RV GCS) and the relative contribution of longitudinal ejection fraction (LEF) and radial ejection fraction (REF) to RVEF using the ReVISION method. Athletes also underwent cardiopulmonary exercise testing [O2 consumption (V̇o2)/kg]. Athletes had significantly higher RVEDVi compared with control subjects (athletes vs. control subjects, 88 ± 11 vs. 65 ± 10 ml/m2, P < 0.001); however, they also demonstrated lower RVEF (56 ± 4% vs. 61 ± 5%, P < 0.001). RV GLS was comparable between the two groups (-22 ± 5% vs. -23 ± 5%, P = 0.24), whereas RV GCS was significantly lower in athletes (-21 ± 4% vs. -26 ± 7%, P < 0.001). Athletes had higher LEF and lower REF contribution to RVEF (LEF/RVEF: 0.50 ± 0.07 vs. 0.42 ± 0.07, P < 0.001; REF/RVEF: 0.33 ± 0.08 vs. 0.45 ± 0.08, P < 0.001). Moreover, the pattern of RV functional shift correlated with V̇o2/kg (LEF/RVEF: r = 0.30, P < 0.05; REF/RVEF: r = -0.27, P < 0.05). RV mechanical adaptation to long-term intense exercise implies a functional shift; the relative contribution of longitudinal motion to global function was increased, whereas the radial shortening was significantly decreased, in athletes. Moreover, this functional pattern correlates with aerobic exercise performance, representing a potential new resting marker of an athletes heart. NEW & NOTEWORTHY Intensive regular physical exercise results in significant changes of right ventricular morphology and function. By separate quantification of the right ventricular longitudinal and radial function, a relative dominance of longitudinal motion and a decrease in radial motion can be observed compared with sedentary controls. Moreover, this contraction pattern correlates with cardiopulmonary fitness. According to these results, this functional shift of the right ventricle may represent a novel marker of an athletes heart.