Complications of percutaneous edge-to-edge mitral valve repair: the role of real-time three-dimensional transesophageal echocardiography.

Percutaneous edge-to-edge mitral valve repair can be performed safely, and reductions in mitral regurgitation can be achieved in a significant proportion of patients. However, complications can arise in a minority of patients. The authors report three cases in which complications of percutaneous mitral valve repair were documented by real-time three-dimensional transesophageal echocardiography. This new imaging technique provides real-time, easily understandable images of valve anatomy and the percutaneous mitral valve repair procedure, which helps guide the decision-making process.

Comparison of a non-invasive arterial pulse contour technique and echo Doppler aorta velocity-time integral on stroke volume changes in optimization of cardiac resynchronization therapy.

AIMS: We investigated the accuracy and feasibility of a non-invasive arterial pulse contour technique for continuous measurement of stroke volume (SV) in optimization of atrioventricular (AV) delay in cardiac resynchronization therapy (CRT), by comparing SV changes assessed by Nexfin CO-Trek® (Nexfin) and echo Doppler aortic velocity-time integral (VTIao). Furthermore, we investigated whether AV-delay optimization increases the effect of CRT when compared with a default AV delay (120 ms). METHODS AND RESULTS: In 23 CRT patients, biventricular pacing (BiVP) was applied at various AV delays, while recording 10 beats preceding BiVP (baseline) and the first 10 BiVP beats, for both methods in parallel. Agreement between Nexfin and VTIao measurements was evaluated (Bland-Altman) on beat-to-beat changes in SV, as well as on effects of BiVP (averaged over 8 beats) at various AV delays. Individual optimal AV delays, for Nexfin (AVopt-n) and VTIao (AVopt-ao), were derived from the second-order polynomial fitted to the effect measurements of 20 patients. In 252 episodes assessed, the difference between measurements (= Nexfin - VTIao) was -0.6 ± 8.1% for beat-to-beat SV changes and -1.3 ± 7.3% for effects of BiVP. Optimal AV delays for Nexfin were well related to AVopt-ao (R(2) = 0.69). The effect (%) of BiVP at the optimal AV delay was significantly larger than at the default AV delay: median difference (range) being +6.3% (0.1-14.4%; P < 0.001) for VTIao and +4.7% (0.0-14.0%; P < 0.001) for Nexfin. CONCLUSION: Individual AV optimization increases the effect of CRT. Nexfin is a promising tool in individual CRT optimization, as Nexfin agrees with VTIao on measuring beat-to-beat SV changes and on assessing relative effects of BiVP on SV at various AV delays.

Redistribution of left ventricular strain by cardiac resynchronization therapy in heart failure patients.

AIMS: The aim of this study was to investigate (i) the baseline patterns of segmental peak myocardial strain (PMS) in heart failure (HF) patients with ventricular conduction delay, (ii) changes in patterns of segmental PMS induced by cardiac resynchronization therapy (CRT), and (iii) whether they differ between CRT responders and non-responders. METHODS AND RESULTS: Segmental and global longitudinal (L-) and radial (R-) PMS measurements derived from speckle tracking were prospectively obtained in 85 HF patients with intraventricular conduction delay before and 6 months after CRT device implantation and in 30 healthy subjects. Segmental strain analysis in HF patients showed pronounced heterogeneity both in longitudinal and in radial directions with the lowest amplitudes in the septum and the highest amplitudes in the lateral and posterior walls. After CRT, 60% of the patients were responders (≥ 15% reduction in end-systolic volume). Before CRT, responders showed higher global R-PMS than non-responders (19.5 ± 13.4 vs.13.1 ± 4.8%, respectively; P = 0.04) despite similar global L-PMS. After CRT, responders showed an increase in L-PMS in most segments and a homogeneous increase in R-PMS, leading to a more uniform pattern of strain and an improved global L-PMS and R-PMS. In contrast, in non-responders, the gain in L-PMS and R-PMS in septal segments was completely offset by a decrease in posterolateral segments, failing to decrease segmental heterogeneity and to increase global L-PMS and R-PMS. CONCLUSION: Heart failure patients with ventricular conduction delay show pronounced heterogeneous patterns of segmental PMS, which can be reversed by CRT.

Comparison of eight echocardiographic methods for determining the prevalence of mechanical dyssynchrony and site of latest mechanical contraction in patients scheduled for cardiac resynchronization therapy.

Prevalence of echocardiographically assessed mechanical dyssynchrony and consistency in detection of the latest mechanical left ventricular (LV) contracting region when different echocardiographic methods are used in the same patient remains ill-defined. The objectives of this study were to evaluate (1) the prevalence of intraventricular mechanical dyssynchrony and (2) consistency of latest mechanical LV contraction using a multiparametric approach derived from tissue Doppler imaging (TDI), 3-dimensional (3D) echocardiography, and speckle tracking in patients scheduled for cardiac resynchronization therapy (CRT). In 63 patients with heart failure scheduled for CRT, 2D echocardiography, TDI, 3D echocardiography, and speckle tracking were prospectively collected and analyzed. Prevalence of dyssynchrony was low for some tissue-velocity derived indexes (11%, 13%, and 43%) but was >or=80% for strain derived by TDI, for systolic dyssynchrony index by 3D echocardiography, and for longitudinal and radial strains by speckle tracking. Prevalence of dyssynchrony was 69% for maximum delay between anteroseptal and posterolateral walls by radial strain. Agreement among dyssynchrony indexes was generally low (kappa -0.02). Agreement of each of these echocardiographic indexes in determining, in the same patient with heart failure, the latest LV mechanical contraction site was also low (no site agreement in 77%). In conclusion, in a typical CRT population there is considerable variability among various techniques that assess prevalence of mechanical dyssynchrony and in identification of the latest mechanical LV contracting region.