Mani A. Vannan

Hemodynamic and Echocardiographic Comparison of the Lotus and CoreValve Transcatheter Aortic Valves in Patients With High and Extreme Surgical Risk: An Analysis From the REPRISE III Randomized Controlled Trial (Repositionable Percutaneous Replacement of Stenotic Aortic Valve through Implantation of Lotus Valve System - Randomized Clinical Evaluation)

Background: Comparative echocardiographic data on transcatheter aortic valve replacement systems from randomized trials are limited. The REPRISE III trial (Repositionable Percutaneous Replacement of Stenotic Aortic Valve through Implantation of Lotus Valve System – Randomized Clinical Evaluation) is a multicenter, randomized comparison of a mechanically expanded (Lotus) versus self-expanding (CoreValve) transcatheter aortic valve replacement device. This analysis rigorously assesses Doppler-derived valve hemodynamics and the impact on outcomes at 1 year in patients with extreme/high surgical risk treated with Lotus and CoreValve from REPRISE III. Methods: REPRISE III includes patients with extreme- and high-risk aortic stenosis. Patients were enrolled at 55 centers. All transthoracic echocardiograms with Doppler were obtained following a standard protocol up to 12 months postimplant and analyzed by a core laboratory. Valve size, mean gradient, aortic valve area, and Doppler velocity index and their impact on clinical outcomes are reported. Additional parameters including paravalvular leak were evaluated using a multiparametric approach. Results: A total of 912 patients were randomly assigned (2:1 ratio; 607 Lotus:305 CoreValve). Median age was 84 years, 51% of the patients were women, and the Society of Thoracic Surgeons score was 6.8±4.1. CoreValve demonstrated lower gradients and larger aortic valve area and Doppler velocity index than Lotus at discharge; the difference decreased in subsequent follow-up up to a year (all P<0.01). Lotus had lower rates of paravalvular leak that persisted over time (P<0.05). Similar outcomes were seen when comparing each valve type by size group (small, medium, large). The hemodynamic differences between valves did not translate into worse clinical outcomes. All-cause mortality was not different between the 2 groups in any of the 3 valve sizes. When comparing patients with normal valve gradients (<20 mm Hg, n=780) with those with abnormal gradients (>20 mm Hg, n=48) in the entire patient population, all-cause mortality was not different. This was also not significant when evaluating each valve type separately. Similarly, there were no differences for aortic valve area >1.1 cm2 or <1.1 cm2 and for Doppler velocity index >0.35 or <0.35 (all P=not significant). Conclusions: Lotus had significantly greater freedom from moderate or severe paravalvular leak and smaller valve area and higher gradients than CoreValve. The hemodynamic differences were not associated with any clinical differences in the composite end point of mortality, disabling stroke, and moderate paravalvular leak or with quality of life at 1 year of follow-up. Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02202434.

Quantitative Three-Dimensional Color Flow Echocardiography of Chronic Mitral Regurgitation: New Methods, New Perspectives, New Challenges

Echocardiography is the imaging modality of choice to quantify chronic mitral regurgitation (MR), and the current American College of Cardiology/American Heart Association and European Society of Cardiology guidelines on valve disease emphasize the central role of quantitative parameters obtained from color flow Doppler (CFD) imaging in grading the severity of chronic MR. However, given the well-described limitations of quantitative CFD imaging, an integrated approach (which includes data from spectral Doppler), and measurements of left ventricular (LV) size and function, are also included in the recommendations for quantitating MR. In the real world, trivial, mild, and severe MR are obvious, and quantitative measures often confirm eyeball assessments of severity. But the classification of ‘‘moderate’’ MR poses uncertainty with respect to visual assessment, and there is considerable variability among interpreters. In fact, the use of descriptors in everyday practice such as ‘‘moderate to severe MR’’ and ‘‘solid moderate MR’’ reflect this uncertainty. It is in this situation in which quantitative methods have the most impact, either confirming moderate MR or upgrading or downgrading the degree of MR, similar to the nature of the benefit seen with stress imaging testing for chest pain in patients with intermediate pretest risk for coronary artery disease. Another more contemporary indication for routine quantification of MR is in the assessment of residual MR after transcatheter or surgical valve repair, when eyeball assessment is often extremely difficult if not impossible. Even if qualitative assessment was possible, accurate quantification is necessary in these circumstances for appropriate clinical decision making.

First report of a simultaneous transcatheter mitral valve‐in‐valve and aortic valve replacement in a left ventricular assist device patient

Transcatheter aortic valve replacement is standard of care for patients with severe aortic stenosis at high risk for surgical aortic valve replacement. Although not intended for treatment of primary aortic insufficiency, several transcatheter aortic valve prostheses have been used to treat patients with severe aortic insufficiency (AI), including patients with left ventricular assist devices (LVAD), in whom significant AI is not uncommon. Similarly, transcatheter valve replacements have been used for valve‐in‐valve treatment, in the pulmonary, aortic, and mitral positions, either via a retrograde femoral approach or antegrade transseptal approach (mitral valve‐in‐valve). In this case report, we report an LVAD patient with severe aortic insufficiency and severe bioprosthetic mitral prosthetic stenosis, in whom we successfully performed transfemoral aortic valve replacement and transfemoral mitral valve‐in‐valve replacement via a transseptal approach.

Functional Anatomy and Dynamics of the Aortic Root

The anatomy of the aortic root is a sophisticated structure uniquely designed to optimize its function. Each component of the aortic root (Fig. 3.1) is deliberately assembled to allow the stroke volume to be ejected as a laminar flow with minimal resistance and minimal tissue wear and tear [1]. This organized action of the components of the aortic root is critical to the efficiency of the left ventricular pump, normal coronary blood flow, and the distinctive flow pattern in the aorta [2–6]. Thus, an understanding of the functional anatomy of the aortic root is essential to understand the clinical consequences of the disruption of this complex structure. This understanding also is key to the surgical repair techniques aimed to restore this sophisticated anatomy in various diseases of the aortic root. The following section will first describe the structure of the aortic root and in the second part describe the coordinated functioning of this complex yet intuitively efficient structure.

Outcomes of Patients With Asymptomatic Aortic Stenosis Followed Up in Heart Valve Clinics

Importance The natural history and the management of patients with asymptomatic aortic stenosis (AS) have not been fully examined in the current era. Objective To determine the clinical outcomes of patients with asymptomatic AS using data from the Heart Valve Clinic International Database. Design, Setting, and Participants This registry was assembled by merging data from prospectively gathered institutional databases from 10 heart valve clinics in Europe, Canada, and the United States. Asymptomatic patients with an aortic valve area of 1.5 cm2 or less and preserved left ventricular ejection fraction (LVEF) greater than 50% at entry were considered for the present analysis. Data were collected from January 2001 to December 2014, and data were analyzed from January 2017 to July 2018. Main Outcomes and Measures Natural history, need for aortic valve replacement (AVR), and survival of asymptomatic patients with moderate or severe AS at entry followed up in a heart valve clinic. Indications for AVR were based on current guideline recommendations. Results Of the 1375 patients included in this analysis, 834 (60.7%) were male, and the mean (SD) age was 71 (13) years. A total of 861 patients (62.6%) had severe AS (aortic valve area less than 1.0 cm2). The mean (SD) overall survival during medical management (mean [SD] follow up, 27 [24] months) was 93% (1%), 86% (2%), and 75% (4%) at 2, 4, and 8 years, respectively. A total of 104 patients (7.6%) died under observation, including 57 patients (54.8%) from cardiovascular causes. The crude rate of sudden death was 0.65% over the duration of the study. A total of 542 patients (39.4%) underwent AVR, including 388 patients (71.6%) with severe AS at study entry and 154 (28.4%) with moderate AS at entry who progressed to severe AS. Those with severe AS at entry who underwent AVR did so at a mean (SD) of 14.4 (16.6) months and a median of 8.7 months. The mean (SD) 2-year and 4-year AVR-free survival rates for asymptomatic patients with severe AS at baseline were 54% (2%) and 32% (3%), respectively. In those undergoing AVR, the 30-day postprocedural mortality was 0.9%. In patients with severe AS at entry, peak aortic jet velocity (greater than 5 m/s) and LVEF (less than 60%) were associated with all-cause and cardiovascular mortality without AVR; these factors were also associated with postprocedural mortality in those patients with severe AS at baseline who underwent AVR (surgical AVR in 310 patients; transcatheter AVR in 78 patients). Conclusions and Relevance In patients with asymptomatic AS followed up in heart valve centers, the risk of sudden death is low, and rates of overall survival are similar to those reported from previous series. Patients with severe AS at baseline and peak aortic jet velocity of 5.0 m/s or greater or LVEF less than 60% have increased risks of all-cause and cardiovascular mortality even after AVR. The potential benefit of early intervention should be considered in these high-risk patients.