Reverse remodeling and the mechanism of mitral regurgitation improvement in patients with dilated cardiomyopathy

Background: Functional mitral regurgitation (MR) is a common finding in dilated cardiomyopathy. Left ventricular (LV) reverse remodeling with LV size reduction and improvement in LV function is a well recognized phenomenon. We aimed to evaluate the impact of LV remodeling on the mechanism leading to functional MR. Methods: Among 188 patients with non-ischemic dilated cardiomyopathy, 10 patients significantly improved their LV function, reduced LV size and MR severity during follow-up (RRMR). A comparison was made between their baseline and follow-up echocardiographic examinations and to a matched-control group of patients who did not improve (no RRMR). LV and left atrium (LA) dimensions and volumes, LV mass (LVM), LV ejection fraction (LVEF) (Simpsons), sphericity index (SI), mitral valve tenting area (TA) coaptation distance (CD), effective regurgitant orifice (ERO), and regurgitant volume were calculated. Multivariable analysis was performed in order to evaluate which echocardiographic parameters related to MR improvement in reverse remodeling. Results: LV and LA dimensions and volumes, LVM, SI, TA, CD, ERO and right ventricle, in the RRMR group significantly decreased at follow-up (p < 0.04 for all). When compared to no RRMR, despite a similar ERO (0.2 ± 0.05 vs. 0.2 ± 0.08, p = 0.13) and a larger regurgitant volume (38 ± 9 vs. 29 ± 8 mL, p = 0.05) and despite similar clinical characteristics and medical treatment we found significantly higher LVEF, smaller LV dimensions and volumes, smaller LVM and SI in the RRMR group (p < 0.05 for all). On multivariable analysis the SI was the sole predictor of RRMR (p = 0.04, OR = 0.76, CI 0.58–0.99). Conclusions: Reverse remodeling characterized by improvement in LV function, reduction in LV size and an associated reduction in MR severity is related to LV SI at baseline.

Neo-LVOT and Transcatheter Mitral Valve Replacement: Expert Recommendations

With the advent of transcatheter mitral valve replacement (TMVR), the concept of the neo-left ventricular outflow tract (LVOT) was introduced and remains an essential component of treatment planning. This paper describes the LVOT anatomy and provides a step-by-step computed tomography methodology to segment and measure the neo-LVOT while discussing the current evidence and outstanding challenges. It also discusses the technical and hemodynamic factors that play a major role in assessing the neo-LVOT. A summary of expert-based recommendations about the overall risk of LVOT obstruction in different scenarios is presented along with the currently available methods to reduce the risk of LVOT obstruction and other post-procedural complications

Survival after intervention in patients with low gradient severe aortic stenosis and preserved left ventricular function

ObjectiveThe outcome of aortic valve replacement for patients with low gradient severe aortic stenosis and preserved ejection fraction has been debated. The aim of the present study was to evaluate the effect of aortic valve intervention on survival in that group.MethodsA cohort of 416 consecutive patients with low gradient severe aortic stenosis (aortic valve area, ≤1 cm2; mean pressure gradient, <40 mm Hg) and preserved ejection fraction (≥50%) were identified from the Sheba Medical Center echocardiography database. Clinical data, aortic valve intervention, and death were recorded.ResultsDuring an average follow-up of 28 months, of 416 study patients (mean age, 76 ± 14 years, 42% men), 97 (23%) underwent aortic valve intervention and 140 (32%) died. Mantel-Byar analysis showed that the cumulative probability of survival was significantly greater after aortic valve intervention. Multivariate analysis revealed a 49% reduction in the risk of death after surgery (P < .05). The survival benefit of aortic valve intervention was comparable with adjustment to older age, aortic valve area ≤ 0.8 cm2, and a low (≤35 cm2/m2) or normal (>35 cm2/m2) stroke volume index.ConclusionsOur findings suggest that aortic valve intervention is associated with improved survival among patients with low gradient severe aortic stenosis and preserved left ventricular function. The presence of either a low or normal stroke volume index did not affect the mortality benefit