Patric Biaggi

Predictors for efficacy of percutaneous mitral valve repair using the MitraClip system: the results of the MitraSwiss registry

Background Percutaneous mitral valve repair (MVR) using the MitraClip system has become a valid alternative for patients with severe mitral regurgitation (MR) and high operative risk. Objective To identify clinical and periprocedural factors that may have an impact on clinical outcome. Design Multi-centre longitudinal cohort study. Setting Tertiary referral centres. Patients Here we report on the first 100 consecutive patients treated with percutaneous MVR in Switzerland between March 2009 and April 2011. All of them had moderate–severe (3+) or severe (4+) MR, and 62% had functional MR. 82% of the patients were in New York Heart Association (NYHA) class III/IV, mean left ventricular ejection fraction was 48% and the median European System for Cardiac Operative Risk Evaluation was 16.9%. Interventions MitraClip implantation performed under echocardiographic and fluoroscopic guidance in general anaesthesia. Main outcome measures Clinical, echocardiographic and procedural data were prospectively collected. Results Acute procedural success (APS, defined as successful clip implantation with residual MR grade ≤2+) was achieved in 85% of patients. Overall survival at 6 and 12 months was 89.9% (95% CI 81.8 to 94.6) and 84.6% (95% CI 74.7 to 91.0), respectively. Univariate Cox regression analysis identified APS (p=0.0069) and discharge MR grade (p=0.03) as significant predictors of survival. Conclusions In our consecutive cohort of patients, APS was achieved in 85%. APS and residual discharge MR grade are important predictors of mid-term survival after percutaneous MVR.

Acute haemodynamic changes after percutaneous mitral valve repair: relation to mid-term outcomes

Background Percutaneous mitral valve repair (MVR) using the Evalve MitraClip has been recently introduced as a potential alternative to surgical MVR. Objective To assess immediate haemodynamic changes after percutaneous MVR using right heart catheterisation. Design Single-centre longitudinal cohort study. Setting Tertiary referral centre. Patients Fifty consecutive non-surgical patients (age 74±14 years, EuroSCORE 26±14) with moderate to severe (3+) and severe (4+) mitral regurgitation (MR) due to functional (56%), degenerative (30%) or mixed (14%) disease were selected. Interventions MitraClip implantation was performed under general anaesthesia with fluoroscopy and echocardiographic guidance. Haemodynamic variables were obtained before and after MVR using standard right heart catheterisation and oximetry. Main outcome measures Haemodynamic changes immediately before and after MVR. Results Acute procedural success (reduction in MR to grade 2+ or less) was achieved in 46 (92%) patients. Mitral valve clipping reduced mean pulmonary capillary wedge pressure (mPCWP) (from 17±7 to 12±5 mm Hg), PCWP v-wave (from 24±11 to 16±7 mm Hg) and mean pulmonary artery pressure (mPAP) (from 29±12 to 24±6 mm Hg), and increased the cardiac index (CI) (from 3.1±1.0 to 3.9±1.1 l/min/m2) (all p<0.05). On Cox univariate regression analysis, mPCWP, PCWP v-wave- and mPAP-changes were associated with death, open-heart surgery for MR and/or hospitalisation for heart failure on follow-up. Conclusion In a heterogeneous population with predominantly functional MR, percutaneous MVR with the Evalve MitraClip system lowers mPCWP, PCWP v-wave and mPAP by 20%, 20% and 8%, respectively, and increases the CI by 32%.

Real-Time Left Ventricular Pressure-Volume Loops During Percutaneous Mitral Valve Repair With the MitraClip System

Background— Percutaneous mitral valve repair with the MitraClip device has emerged as an alternative to surgery for treating severe mitral regurgitation. However, its effects on left ventricular loading conditions and contractility have not been investigated yet. Methods and Results— Pressure-volume loops were recorded throughout the MitraClip procedure using conductance catheter in 33 patients (mean age, 78±10 years) with functional (45%), degenerative (48%), or mixed (6%) mitral regurgitation. Percutaneous mitral valve repair increased end-systolic wall stress (WSES; from [median] 184 mm Hg [interquartile range (IQR), 140–200 mm Hg] to 209 mm Hg [IQR, 176–232 mm Hg]; P=0.001) and decreased end-diastolic WS (WSED; from 48 mm Hg [IQR, 28–58 mm Hg] to 34 mm Hg [IQR, 21–46 mm Hg]; P=0.005), whereas the end-systolic pressure-volume relationship was not significantly affected. Conversely, cardiac index increased (from 2.6 L·min−1·m−2 [IQR, 2.2–3.0 L·min−1·m−2] to 3.2 L·min−1·m−2 [IQR, 2.6–3.8 L·min−1·m−2]; P<0.001) and mean pulmonary capillary wedge pressure decreased (from 15 mm Hg [IQR, 12–20 mm Hg] to 12 mm Hg [IQR, 10–13 mm Hg]; P<0.001). Although changes in WSES were not correlated with changes in cardiac index, changes in WSED correlated significantly with changes in mean pulmonary capillary wedge pressure (r=0.63, P<0.001). Total mechanical energy assessed by the pressure-volume area remained unchanged, resulting in a more favorable index of forward output (cardiac index) to mechanical energy (pressure-volume area) after mitral valve repair. On follow-up (153±94 days), New York Heart Association functional class was reduced from 2.9±0.6 to 1.9±0.5 (P<0.001) at 3 months, and echocardiographic follow-up documented a stepwise reduction in end-diastolic volume (from 147 mL [IQR, 95–191 mL] to 127 mL [IQR, 82–202 mL]; P=0.036). Conclusions— Percutaneous mitral valve repair improves hemodynamic profiles and induces reverse left ventricular remodeling by reducing left ventricular preload while preserving contractility. In nonsurgical candidates with compromised left ventricular function, MitraClip therapy could be considered an alternative to surgical mitral valve repair.

Left ventricular non-compaction: prevalence in congenital heart disease.

INTRODUCTION Left ventricular non-compaction cardiomyopathy (LVNC) is a rare cardiomyopathy, originally described as an isolated disease without other structural cardiac abnormalities. The aim of this study was to explore the prevalence of LVNC among adults with different types of congenital heart disease. METHODS From our databases we identified adults with congenital heart disease who fulfilled diagnostic criteria for LVNC. We report frequencies of associated congenital cardiac defects and the prevalence of LVNC among patients with different congenital heart defects. RESULTS From a total of 202 patients with LVNC, 24 patients (12%; mean age 32 ± 11 years, 19 males) had additional congenital cardiac defects. Associated defects were left ventricular outflow tract abnormalities in 11 patients (46%), including 7 uni- or bicuspid aortic valves; two aortic coarctations; one diffuse aortic hypoplasia and one subaortic stenosis, Ebstein anomaly in 6 patients (25%), tetralogy of Fallot in two (8%), and double outlet right ventricle in one patient (4%). In our cohort, the prevalence of LVNC was highest among patients with Ebstein anomaly (6/40, 15%), followed by aortic coarctation (2/60, 3%), tetralogy of Fallot (3/129, 2%) and uni- or bicuspid aortic valves (7/963, 1%). CONCLUSION In adults, various forms of congenital heart disease are associated with LVNC, particularly stenotic lesions of the left ventricular outflow tract, Ebstein anomaly, and tetralogy of Fallot. In the future, studying these patients in more depth may provide a better understanding of the interplay between genetic and hemodynamic factors that lead to the phenotype of LVNC.

Gender, Age, and Body Surface Area are the Major Determinants of Ascending Aorta Dimensions in Subjects With Apparently Normal Echocardiograms

BACKGROUND Limited data have been published on the normal size of the ascending aorta (AA) measured using transthoracic echocardiography (TTE). METHODS AA diameters were measured in 1799 patients with normal cardiac findings on TTE and compared with the diameters of the sinus of Valsalva (SoV). RESULTS Mean diameters in men and women, respectively, were 3.4 and 3.1 cm for the SoV and 3.2 and 3.0 cm for the AA. The sizes of the SoV and the AA showed strong correlations with age, age squared, and body surface area. The 5th and 95th percentile curves for the SoV and AA showed faster growth of diameters in early adulthood compared with old age. The dimensions of the SoV were larger than those of the AA (mean differences, 0.19 cm in men and 0.08 cm in women), and the difference between the SoV and AA was negatively correlated with age. CONCLUSION The findings of this study stress the importance of indexing dimensions of the SoV and the AA to age and body surface area separately for men and women.

Different Prognostic Value of Functional Right Ventricular Parameters in Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia

Background—The value of standard 2-dimensional transthoracic echocardiographic parameters for risk stratification in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is controversial. Methods and Results—We investigated the impact of RV fractional area change (FAC) and tricuspid annulus plane systolic excursion (TAPSE) for the prediction of major adverse cardiovascular events (MACE) defined as the occurrence of cardiac death, heart transplantation, survived sudden cardiac death, ventricular fibrillation, sustained ventricular tachycardia, or arrhythmogenic syncope. Among 70 patients who fulfilled the 2010 ARVC/D Revised Task Force Criteria and underwent baseline transthoracic echocardiography, 37 (53%) patients experienced MACE during a median follow-up period of 5.3 (interquartile range, 1.8–9.8) years. Average values for FAC, TAPSE, and TAPSE indexed to body surface area (BSA) decreased over time (P=0.03 for FAC, P=0.03 for TAPSE, and P=0.01 for TAPSE/BSA, each versus baseline). In contrast, median RV end-diastolic area increased (P=0.001 versus baseline). Based on the results of Kaplan–Meier estimates, the time between baseline transthoracic echocardiography and experiencing MACE was significantly shorter for patients with FAC <23% (P<0.001), TAPSE <17 mm (P=0.02), or right atrial short axis/BSA ≥25 mm/m2 (P=0.04) at baseline. A reduced FAC constituted the strongest predictor of MACE (hazard ratio, 1.08 per 1% decrease; 95% confidence interval, 1.04–1.12; P<0.001) on bivariable analysis. Conclusions—This long-term observational study indicates that TAPSE and dilation of right-sided cardiac chambers are associated with an increased risk for MACE in patients with ARVC/D with advanced disease and a high risk for adverse events. However, FAC is the strongest echocardiographic predictor of adverse outcome in these patients. Our data advocate a role for transthoracic echocardiography in risk stratification in patients with ARVC/D, although our results may not be generalizable to lower-risk ARVC/D cohorts.

Right Heart Assessment by Echocardiography: Gender and Body Size Matters

BACKGROUND Published reference values for echocardiographic measurements of right-heart dimensions and function do not stratify for gender and body size. The aim of this study was therefore to assess the impact of gender and biometric characteristics on right-heart dimensions and function. METHODS From the echocardiography database at a tertiary care center, 1,625 subjects (mean age, 44 ± 14 years; 47% men) with normal echocardiographic findings between 2000 and 2009 were identified. Gender differences and association with body surface area were assessed retrospectively for right atrial long-axis and short-axis dimensions, right ventricular short-axis dimension, end-diastolic and end-systolic right ventricular area, right ventricular fractional area change, and tricuspid annular plane systolic excursion. The impact of normal values stratified for gender and body surface area was tested in 24 patients with moderate-sized to large atrial septal defects. RESULTS All dimensional right-heart measurements were significantly lower in women. Differences became smaller when measurements were indexed for body surface area, but significant differences persisted, particularly for right ventricular end-diastolic area (7.9 ± 1.6 vs 8.7 ± 1.8 cm(2)/m(2), P < .001) and right ventricular end-systolic area (4.0 ± 1.2 vs 4.7 ± 1.4 cm(2)/m(2), P < .001). Fractional area change and tricuspid annular plane systolic excursion indexed to body surface area were significantly higher in women (50 ± 7% vs 46 ± 9% and 14 ± 3 vs 12 ± 2 mm/m(2), respectively, P < .001 for both comparisons). The use of upper reference ranges for end-diastolic right ventricular area stratified for gender and body surface area improved the detection of enlarged right ventricles in patients with moderate-sized to large atrial septal defects (92% vs 54%, P < .007). CONCLUSIONS Gender and body surface area are important determinants of right ventricular dimensions and systolic function as measured on two-dimensional echocardiography. The investigators thus propose the use of measurements indexed to body surface area, with upper and lower reference ranges stratified for gender.

Safety and feasibility of novel technology fusing echocardiography and fluoroscopy images during MitraClip interventions.

AIMS The EchoNavigator (EN) software (Philips Healthcare, Best, The Netherlands) enables real-time fusion of echocardiography and fluoroscopy by co-registration of the echocardiography probe on the x-ray image. We aimed to evaluate the feasibility and safety of this novel software during MitraClip procedures. METHODS AND RESULTS Twenty-one patients were treated with the support of EchoNavigator software (EN+ patients). The primary (safety) endpoint was the total radiation dose. Secondary endpoints were fluoroscopy and total procedure time. The measurements were compared to those of 21 patients treated immediately before the installation of EchoNavigator (EN- patients). More MitraClips (45 vs. 36) were implanted in the EN+ group, mirroring more complex interventions in this group. In EN+ patients, radiation dose (Gy/cm2) was similar compared to EN- patients (146.5±123.6 vs.146.8±134.1, p=0.9). Total procedure time (minutes) was similar in the EN+ group compared to EN- patients (136.2±50.2 vs. 125.7±51.2, p=0.5). The main benefit of the EchoNavigator is the automated real-time fusion of echocardiography and fluoroscopy, leading to easier catheter manipulation. CONCLUSIONS The use of EchoNavigator software was feasible and safe in all study patients. Further studies are necessary to confirm the benefits of using this software.

Hybrid Imaging During Transcatheter Structural Heart Interventions

Fusion of different imaging modalities has gained increasing popularity over the last decade. However, most fusions are done between static rather than dynamic images. In order to adequately visualize the complex three-dimensional structures of the beating heart, high-temporal and spatial image resolutions are mandatory. Currently, only the combination of transesophageal echocardiography with fluoroscopy allows real-time image fusion of high quality during structural heart disease (SHD) interventions. The use of markers as well as real-time image overlay greatly facilitates communication between SHD team members and potentially increases procedural success while reducing radiation dose and use of contrast. However, to date there is only limited evidence that fusion imaging improves safety and outcomes of SHD interventions. This review highlights the benefits of fusion imaging during SHD interventions such as transseptal puncture and closure of atrial septal defects and left atrial appendage as well as interventions on the mitral and aortic valve.

Assessment of mitral valve area during percutaneous mitral valve repair using the MitraClip system: comparison of different echocardiographic methods.

Background—Quantification of the mitral valve area (MVA) is important to guide percutaneous mitral valve repair using the MitraClip system. However, little is known about how to best assess MVA in this specific situation. Methods and Results—Immediately before and after MitraClip implantation, comprehensive 3-dimensional (3D) transesophageal echocardiography data were acquired for MVA assessment by the pressure half-time method and by two 3D quantification methods (mitral valve quantification software and 3D quantification software). In addition, transmitral gradients by continuous-wave Doppler (dPmeanCW) were measured to indirectly assess MVA. Data are given as median (interquartile range). Thirty-three patients (39% women) with a median age of 77.1 years (12.4 years) were studied. Before intervention, the median MVAs by the pressure half-time method, mitral valve quantification software, and 3D quantification software were 4.4 cm2 (2.0 cm2), 4.7 cm2 (2.4 cm2), and 6.2 cm2 (2.4 cm2), respectively (P<0.001). After intervention, MVA was reduced to 1.9 cm2 (0.7 cm2), 2.1 cm2 (1.1 cm2), and 2.8 cm2 (1.1 cm2), respectively (P=0.001). The median values for dPmeanCW before and after intervention were 1.0 mm Hg (1.0 mm Hg) and 3.0 mm Hg (3.0 mm Hg; P<0.001), respectively. At discharge, the median dPmeanCW was 4.0 mm Hg (3.0 mm Hg). In multivariate regression analyses including body surface area, the 3 different MVA methods, and dPmeanCW, a post-dPmeanCW ≥5 mm Hg was the best independent predictor of an elevated transmitral gradient at discharge. Conclusions—Transmitral gradients by continuous-wave Doppler are quick, feasible in all patients, and superior to direct peri-interventional assessment of MVA. A postinterventional transmitral gradient by continuous-wave Doppler of ≥5 mm Hg best predicted elevated transmitral gradients at discharge.