Aortic Regurgitation and Left Ventricular Remodeling After Transcatheter Aortic Valve Implantation

Five-year outcomes with self-expanding versus balloon-expandable TAVI in patients with left ventricular systolic dysfunction

BACKGROUND

The importance of transcatheter heart valve (THV) design on clinical outcome in patients with aortic stenosis (AS) and left ventricular (LV) systolic dysfunction remains unknown.

OBJECTIVES

We aimed to compare 5-year outcomes of patients with severe AS and reduced LV ejection fraction (LVEF), undergoing transcatheter aortic valve implantation (TAVI) with balloon-expandable vs. self-expanding THVs.

METHODS

In a retrospective analysis from the Bern TAVI registry, patients with LVEF <50% who underwent TAVI with either balloon-expandable or self-expanding THVs were included. A 1:1 propensity-score matching was performed to account for baseline differences between groups.

RESULTS

A total of 759 patients were included between August 2007 and December 2022, and propensity-score matching resulted in 134 pairs. Technical success was achieved in over 85% of patients, and was similar in both groups. Self-expanding THVs were associated with a lower mean transvalvular gradient (7.1 ± 3.7 mmHg vs. 9.9 ± 4.3 mmHg; P < .001) and a higher incidence of ≥mild-to-moderate paravalvular regurgitation (36.3% vs. 11.3%; P < .001) compared to balloon-expandable THVs. At 5 years, patients treated with a self-expanding THV had higher all-cause mortality than those with a balloon-expandable THV (67.8% vs. 55.8%, HRadjusted: 1.44; 95% CI: 1.02-2.03; P = .037). There were no significant differences in other clinical outcomes up to 5 years between groups.

CONCLUSIONS

In the setting of LV systolic dysfunction, patients treated with a self-expanding THV had higher risk of 5-year mortality compared to patients treated with a balloon-expandable THV.

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Cardiac Magnetic Resonance for Structural Aortic Valve Stenosis Procedures

The number of structural aortic valve procedures has increased significantly in recent years. Pre-procedural planning and follow-up with noninvasive testing are essential. Although cardiac magnetic resonance (CMR) is the gold standard for assessing left ventricular mass, volume, and function, it is not performed routinely in patients undergoing structural interventions. CMR can provide useful information for pre- and post-procedural assessment, including quantification of cardiac function, myocardial assessment, grading of the severity of valvular heart disease, and evaluation of extracardiac anatomy while avoiding the limitations of other non-invasive modalities. Here, we review the use cases, future perspectives, and limitations of CMR for patients undergoing structural aortic valve procedures.

The impact of transcatheter aortic valve implantation (TAVI) on mitral regurgitation - a single center study

BACKGROUND

The coexistence of mitral regurgitation (MR) and severe aortic stenosis (AS) has been associated with worse outcomes in patients undergoing transcatheter aortic valve implantation (TAVI). Herein, the aim was to assess the etiology and degree of MR in an unselected TAVI population and investigate the impact of MR reduction at mid-term follow-up.

METHODS

Patients subjected to TAVI as a treatment for severe AS in a single center were retrospectively analyzed. The primary endpoint was the MR reduction after TAVI. The secondary endpoint was all-cause mortality and heart failure hospitalization at a 3-year follow-up.

RESULTS

Patients undergoing TAVI (n = 283) in the years 2017-2019 were screened for the presence of hemodynamically significant MR. Sixty-nine subjects (24.4%) with severe (16, 23.2%) and moderate (53, 76.8%) MR were included. The primary MR was predominant (39 subjects, 56.5%). The median age of the patients was 82 years. MR improved in 25 patients (36.2%, p < 0.001). Baseline severe MR was more prone to reduce (8 subjects, 50%) than moderate (17 subjects, 32.1%, p = 0.04). The primary MR improved in 14 patients (35.9%), while secondary in 11 patients (36.7%, p = 1). Patients showing MR reduction had lower mortality (8 vs. 29.55%, p = 0.047) and were less frequently hospitalized (20 vs. 45.45%, p = 0.03) at 3-year follow-up.

CONCLUSIONS

Hemodynamically significant MR improves after TAVI regardless of its etiology. Moreover, MR reduction after TAVI is associated with better clinical outcomes.

Reverse Left Ventricular Remodeling With Transcatheter Interventions in Chronic Heart Failure Syndromes: An Updated Appraisal of the Device Landscape

Chronic heart failure (HF) is a clinical syndrome of myocardial dysfunction characterized by inadequate cardiac output or preserved output that can only be achieved by sustaining abnormal loading conditions. Morphologically, HF with reduced left ventricular function results in progressive chamber remodeling, meaning the ventricle dilates, operating at larger end-diastolic and end-systolic volumes, and takes on an abnormal, spherical shape that increases wall stress. Reverse remodeling is the goal of HF-directed therapies and can be achieved by biological means, ie, altering the loading conditions that, at a cellular level, promote myocardial dysfunction, or physical means, ie, directly altering myocardial mass or shape. In this review, we highlight the existing and emerging device-based mechanisms for biologically and physically reverse remodeling the left ventricle in chronic HF.

Impact of Mild Paravalvular Regurgitation on Long-Term Clinical Outcomes After Transcatheter Aortic Valve Implantation

The impact of mild paravalvular regurgitation (PVR) after transcatheter aortic valve implantation (TAVI) remains controversial. We evaluated the impact of mild PVR after TAVI on long-term clinical outcomes. We included patients who underwent TAVI for severe symptomatic aortic stenosis between December 2008 and June 2019 at 2 international centers and compared all-cause death between the group with mild PVR (group 1) and the group with none or trace PVR (group 2). PVR was categorized using a 3-class grading scheme, and patients with PVR ≧ moderate and those who were lost to follow-up were excluded. This retrospective analysis included 1,404 patients (mean age 81.7 ± 6.5 years, 58.0% women). Three hundred fifty eight patients (25.5%) were classified into group 1 and 1,046 patients (74.5%) into group 2. At baseline, group 1 was older and had a lower body mass index, worse co-morbidities, and more severe aortic stenosis. To account for these differences, propensity score matching was performed, resulting in 332 matched pairs. Within these matched groups, during a mean follow-up of 3.2 years, group 1 had a significantly lower survival rate at 5 years (group 1: 62.0% vs group 2: 68.0%, log-rank p = 0.029, hazard ratio: 1.41 [95% confidence interval: 1.04 to 1.91]). In the matched cohort, patients with mild PVR had a significant 1.4-fold increased risk of mortality at 5 years after TAVI compared with those with none or trace PVR. Further studies with more patients are needed to evaluate the impact of longer-term outcomes.

Quantitative assessment of aortic regurgitation following transcatheter aortic valve replacement

Introduction: Transcatheter aortic valve replacement (TAVR) is expanding to lower risk and younger patients with severe symptomatic aortic valve disease. Despite clinical and technological improvements, post-procedural aortic regurgitation (AR) remains a limitation of TAVR, particularly when compared to surgical aortic valve replacement. Although several methods for AR quantification after TAVR are currently available, its exact graduation in everyday clinical practice remains challenging.Areas covered: This review describes the currently available evaluation methods of AR after TAVR, with a special emphasis on the quantitative assessment using videodensitometric angiography, echocardiography and cardiac magnetic resonance imaging.Expert opinion: In the majority of clinical scenarios, satisfactory evaluation of post-TAVR AR can be achieved with a combination of post-procedural angiography, hemodynamic indices and transthoracic echocardiography. Nevertheless, some TAVR patients show 'intermediate' forms of post-procedural AR, in which quantitative evaluation is mandatory for prognostic purposes and further decision-making. Notably, interpretation of quantitative measures early post-TAVR is challenging because of the lack of left ventricular enlargement. Video-densitometric angiography is an emerging method that appears to be clinically attractive for immediate post-TAVR assessment, but requires further validation in everyday clinical practice.

Cardiovascular magnetic resonance and transesophageal echocardiography in patients with prosthetic valve paravalvular leaks: towards an accurate quantification and stratification

BACKGROUND

Objective assessment of prosthetic paravalvular leak (PVL) is complex and challenging even in transesophageal echocardiography (TEE). Our aim was to assess the value of cardiovascular magnetic resonance (CMR) in quantifying PVL in aortic (AVR) or mitral valve (MVR) replacement.

METHODS

Thirty-one patients (62 ± 15.1 years, 63% males) with a preliminary diagnosis of significant PVL (AVR, n-23; MVR, n = 8) were recruited. The TEE PVL grading was based on the semi-quantitative (SQ) TEE according to the VARC II PVL classification (%PVL: mild < 10%; moderate 10%-30%; severe > 30%). Non-contrast CMR studies were acquired at 1.5 T with a quantitative approach (phase-contrast velocity encoded imaging). The CMR PVL severity was classified according to regurgitant fraction (RF: (1) mild ≤ 20%, (2) moderate 21%-39%, or (3) severe ≥ 40%).

RESULTS

All patients revealed symptoms of heart failure (71%: New York Heart Association [NYHA] II; 91%: N-terminal pro-B-type natriuretic peptide [NT-proBNP] > 150 pg/ml) and typical cardiovascular disease risk factors. The SQ-TEE results revealed several categories: (1) mild (n = 5; 16%), (2) moderate (n = 21; 67%), and (3) severe (n = 5; 16%) PVL. However, CMR PVL RF reclassified the severity of PVL: (1) mild to moderate (in 80%), (2) moderate to severe (in 47%), and (3) severe to moderate (in 40%). The receiver operating characteristic analysis showed that SQ-TEE and CMR PVL-vol and -RF predicted the upper tertile of NT-proBNP (> 2000 pg/ml) with the best sensitivity for CMR parameters.

CONCLUSION

The SQ-TEE showed moderate agreement with CMR and underestimated a considerable number of AVR or MVR-PVL.

Ex Vivo Pilot Study of Cardiac Magnetic Resonance Velocity Mapping for Quantification of Aortic Regurgitation in a Porcine Model in the Presence of a Transcatheter Heart Valve

Accuracy of aortic regurgitation (AR) quantification by magnetic resonance (MR) imaging in the presence of a transcatheter heart valve (THV) remains to be established. We evaluated the accuracy of cardiac MR velocity mapping for quantification of antegrade flow (AF) and retrograde flow (RF) across a THV and the optimal slice position to use in cardiac MR imaging. In a systematic and fully controlled laboratory ex vivo setting, two THVs (Edwards SAPIEN XT, Medtronic CoreValve) were tested in a porcine model (n = 1) under steady flow conditions. Results showed a high level of accuracy and precision. For both THVs, AF was best measured at left ventricular outflow tract level, and RF at ascending aorta level. At these levels, MR had an excellent repeatability (ICC > 0.99), with a tendency to overestimate (4.6 ± 2.4% to 9.4 ± 7.0%). Quantification of AR by MR velocity mapping in the presence of a THV was accurate, precise, and repeatable in this pilot study, when corrected for the systematic error and when the best MR slice position was used. Confirmation of these results in future clinical studies would be a step forward in increasing the accuracy of the assessment of paravalvular AR severity.

Effect of Breviscapine on Recovery of Viable Myocardium and Left Ventricular Remodeling in Chronic Total Occlusion Patients After Revascularization: Rationale and Design for a Randomized Controlled Trial

BACKGROUND How to speed the recovery of viable myocardium in chronic total occlusion (CTO) patients after revascularization is still an unsolved problem. Breviscapine is widely used in cardiovascular diseases. However, there has been no study focused on the effect of breviscapine on viable myocardium recovery and left ventricular remodeling after CTO revascularization. MATERIAL AND METHODS We propose to recruit 78 consecutive coronary artery disease (CAD) patients with CTO during a period of 12 months. They will be randomly assigned to receive either breviscapine (40 mg) or placebo in the following 12 months. Blood tests, electrocardiogram, and Major Adverse Cardiac Events (MACE) will be collected at baseline and the follow-up visits at 1, 3, 6, 9, and 12 months. Low-dose dobutamine MRI will be applied for the assessment of viable myocardium, microcirculation perfusion, and left ventricular remodeling, and the concentrations of angiogenic cytokine, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) will be investigated at baseline and at 1- and 12-month follow-up. The recovery of viable myocardium after revascularization in CTO patients was the primary endpoint. Improvement of microcirculation perfusion, left ventricular remodeling, peripheral concentrations of VEGF and bFGF as well as MACE will be the secondary endpoints. RESULTS Breviscapine treatment obviously improve the recovery of viable myocardium, myocardial microcirculation perfusion, and left ventricular remodeling after revascularization in CTO patients, and reduce the occurrence of MACE. We also will determine if breviscapine increases the peripheral blood angiogenic cytokine concentrations of VEGF and bFGF. CONCLUSIONS This study will aim to demonstrate the effect of breviscapine on the recovery of viable myocardium and left ventricular remodeling in CTO patients after revascularization.

Cardiovascular magnetic resonance assessment of 1st generation CoreValve and 2nd generation Lotus valves

OBJECTIVES

We sought to compare using serial CMR, the quantity of AR and associated valve hemodynamics, following the first-generation CoreValve (Medtronic, Minneapolis, MN) and the second-generation Lotus valve (Boston Scientific, Natick, MA).

BACKGROUND

Aortic regurgitation (AR) following Transcatheter Aortic Valve Replacement (TAVR) confers a worse prognosis and can be accurately quantified using cardiovascular magnetic resonance (CMR). Second generation valves have been specifically designed to reduce paravalvular AR and improve clinical outcomes.

METHODS

Fifty-one patients (79.0 ± 7.7 years, 57% male) were recruited and imaged at three time points: immediately pre- and post-TAVR, and at 6 months.

RESULTS

CMR-derived AR fraction immediately post-TAVR was greater in the CoreValve compared to Lotus group (11.7 ± 8.4 vs. 4.3 ± 3.4%, P = 0.001), as was the frequency of ≥moderate AR (9/24 (37.5%) versus 0/27, P < 0.001). However, at 6 months AR fraction had improved significantly in the CoreValve group such that the two valve designs were comparable (6.4 ± 5.0 vs 5.6 ± 5.3%, P = 0.623), with no patient in either group having ≥moderate AR. The residual peak pressure gradient immediately following TAVR was significantly lower with CoreValve compared to Lotus (14.1 ± 5.6 vs 25.4 ± 11.6 mmHg, P = 0.001), but again by 6 months the two valve designs were comparable (16.5 ± 9.4 vs 19.7 ± 10.5 mmHg, P = 0.332). There was no difference in the degree of LV reverse remodeling between the two valves at 6 months.

CONCLUSION

Immediately post-TAVR, there was significantly less AR but a higher residual peak pressure gradient with the Lotus valve compared to CoreValve. However, at 6 months both devices had comparable valve hemodynamics and LV reverse remodeling.

Progression and Prognosis of Paravalvular Regurgitation After Transcatheter Aortic Valve Implantation

BACKGROUND

The impact of paravalvular regurgitation (PVR) following transcatheter aortic valve implantation (TAVI) remains uncertain.

OBJECTIVE

To evaluate the impact of PVR on mortality and hospital readmission one year after TAVI.

METHODS

Between January 2009 and June 2015, a total of 251 patients underwent TAVI with three different prostheses at two cardiology centers. Patients were assessed according to PVR severity after the procedure.

RESULTS

PVR was classified as absent/trace or mild in 92.0% (n = 242) and moderate/severe in 7.1% (n = 18). The moderate/severe PVR group showed higher levels of aortic calcification (22% vs. 6%, p = 0.03), higher serum creatinine (1.5 ± 0.7 vs. 1.2 ± 0.4 mg/dL, p = 0.014), lower aortic valve area (0.6 ± 0.1 vs. 0.7 ± 0.2 cm2, p = 0.05), and lower left ventricular ejection fraction (49.2 ± 14.8% vs. 58.8 ± 12.1%, p = 0.009). Patients with moderate/severe PVR had more need for post-dilatation (p = 0.025) and use of larger-diameter balloons (p = 0.043). At one year, all-cause mortality was similar in both groups (16.7% vs. 12%, p = 0.08), as well as rehospitalization (11.1% vs. 7.3%, p = 0.915). PVR grade significantly reduced throughout the first year after the procedure (p < 0.01). The presence of moderate/severe PVR was not associated with higher one-year mortality rates (HR: 0.76, 95% CI: 0.27-2.13, p = 0.864), rehospitalization (HR: 1.08, 95% CI: 0.25-4.69, p=0.915), or composite outcome (HR: 0.77, 95% CI: 0.28-2.13, p = 0.613).

CONCLUSION

In this sample, moderate/severe PVR was not a predictor of long-term mortality or rehospitalization. (Arq Bras Cardiol. 2017; [online].ahead print, PP.0-0).

Update on the significance of postprocedural aortic regurgitation after transcatheter aortic valve replacement on postprocedural prognosis

Transcatheter aortic valve replacement (TAVR) is an established therapy for patients with aortic stenosis and a high surgical risk. Recent data on intermediate-risk patients will probably enlarge the indication for TAVR. In the beginning of the TAVR era, relevant (>mild) aortic regurgitation (AR) was a common finding after TAVR; it was associated with worse outcome compared with patients without significant AR. To date, several improvements in imaging, grading of severity and treatment have been done and will be discussed in this article. AR after TAVR still is a strong and independent predictor of 1-year mortality and every effort should be made to prohibit its development.

The impact of trans-catheter aortic valve replacement induced left-bundle branch block on cardiac reverse remodeling

BACKGROUND

Left bundle branch block (LBBB) is common following trans-catheter aortic valve replacement (TAVR) and has been linked to increased mortality, although whether this is related to less favourable cardiac reverse remodeling is unclear. The aim of the study was to investigate the impact of TAVR induced LBBB on cardiac reverse remodeling.

METHODS

48 patients undergoing TAVR for severe aortic stenosis were evaluated. 24 patients with new LBBB (LBBB-T) following TAVR were matched with 24 patients with a narrow post-procedure QRS (nQRS). Patients underwent cardiovascular magnetic resonance (CMR) prior to and 6 m post-TAVR. Measured cardiac reverse remodeling parameters included left ventricular (LV) size, ejection fraction (LVEF) and global longitudinal strain (GLS). Inter- and intra-ventricular dyssynchrony were determined using time to peak radial strain derived from CMR Feature Tracking.

RESULTS

In the LBBB-T group there was an increase in QRS duration from 96 ± 14 to 151 ± 12 ms (P < 0.001) leading to inter- and intra-ventricular dyssynchrony (inter: LBBB-T 130 ± 73 vs nQRS 23 ± 86 ms, p < 0.001; intra: LBBB-T 118 ± 103 vs. nQRS 13 ± 106 ms, p = 0.001). Change in indexed LV end-systolic volume (LVESVi), LVEF and GLS was significantly different between the two groups (LVESVi: nQRS -7.9 ± 14.0 vs. LBBB-T -0.6 ± 10.2 ml/m2, p = 0.02, LVEF: nQRS +4.6 ± 7.8 vs LBBB-T -2.1 ± 6.9%, p = 0.002; GLS: nQRS -2.1 ± 3.6 vs. LBBB-T +0.2 ± 3.2%, p = 0.024). There was a significant correlation between change in QRS and change in LVEF (r = -0.434, p = 0.002) and between change in QRS and change in GLS (r = 0.462, p = 0.001). Post-procedure QRS duration was an independent predictor of change in LVEF and GLS at 6 months.

CONCLUSION

TAVR-induced LBBB is associated with less favourable cardiac reverse remodeling at medium term follow up. In view of this, every effort should be made to prevent TAVR-induced LBBB, especially as TAVR is now being extended to a younger, lower risk population.

Echocardiographic follow-up after transcatheter aortic valve replacement

The use of transcatheter aortic valve replacement (TAVR) for high-risk patients with aortic stenosis has rapidly increased during the past years. Accordingly, more and more patients are referred for a follow-up echocardiographic study after TAVR. However, the echocardiographic evaluation of patients who underwent TAVR places specific demands on echocardiographers. Furthermore, TAVR may be associated with new types of complications, which are frequently unrecognized or underestimated due to lack of familiarity with the normal and pathological appearance of TAVR. Therefore, this review summarizes the echocardiographic parameters describing the structural and functional status of bioprostheses used in TAVR, procedures taking into account their peculiar hemodynamics. We also describe the strengths and the limitations of echocardiography and of other imaging modalities in detecting long-term complications of TAVR (eg, infective endocarditis, thrombosis). The aim of this review was to serve as a guide for a structured echocardiographic follow-up of TAVR patients, as well as for the echocardiographic diagnosis of the procedure-associated complications.

Correlation of CoreValve implantation 'true cover index' with short and mid-term aortic regurgitation: A novel index

BACKGROUND

'Cover index' has been proposed to appraise the congruence between the aortic annulus and the device, with the assumption of not taking into account the actual device implantation depth. The aim of this study was to investigate whether the annulus-prosthesis mismatch, as expressed with the new proposed 'true cover index' according to actual implantation depth, can predict aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI).

METHODS

Patients who had undergone TAVI with the self-expandable CoreValve device, were retrospectively studied. All available prosthesis sizes were ex-vivo scanned and the precise diameter at 0.3mm intervals along each device was measured. The 'true cover index' was evaluated, as a ratio of the following: 100×([prosthesis actual diameter at implantation depth-annulus diameter]/prosthesis actual diameter at implantation depth). AR was echocardiographically evaluated at discharge and 30days and classified as prominent if moderate, or trivial if none or mild.

RESULTS

Overall, 120 patients who had undergone TAVI, were considered eligible for the study. 'True cover index' was statistically significantly lower among patients with prominent AR in comparison with trivial AR at discharge (5.7±4.8mm vs 9±5.1, p=0.025), as well as at one month post-TAVI (5.4±5.1mm vs 9.0±5.1, p=0.023), indicating increased AR for smaller index. After adjustment for severe annulus calcification, impaired baseline LVEF and previous valvuloplasty, it remained an independent predictor of one month prominent AR (OR: 0.854, CI: 0.730-0.999; p=0.048). 'True cover index' of <4.3 was shown to predict one-month prominent AR with sensitivity =75% and specificity =82.5%.

CONCLUSIONS

'True cover index' is strongly and independently correlated with the short and mid-term AR after CoreValve implantation.

A granular approach to improve reproducibility of the echocardiographic assessment of paravalvular regurgitation after TAVI

Paravalvular leak (PVL) after transcatheter aortic valve implantation (TAVI) is challenging to quantitate. Transthoracic echocardiography (TTE) is the main tool used for the assessment of PVL but is modestly reproducible. We sought to develop a reproducible echocardiographic approach to assess PVL in the post-TAVI setting. Four observers independently analyzed eleven parameters of PVL severity in 50 pre-discharge TTE studies performed after TAVI. The parameters included color-Doppler parameters [jet circumferential extent (CE) and planimetered vena contracta area in the short-axis view and jet breadth and qualitative features in the long-axis views], continuous-wave Doppler parameters [jet velocity time integral (VTI) and pressure half time (PHT)], quantitative Doppler parameters (regurgitation volume and fraction and effective regurgitant orifice area), aortic diastolic flow reversal and valve stent eccentricity. Intraclass correlation coefficient (ICC) and coefficient of variation (CV) for numerical parameters and kappa coefficient (κ) for categorical parameters were calculated for inter- and intra-observer comparisons. Inter-observer ICC was highest and CV lowest for CE (0.88 and 0.36), jet origin breadth (0.82 and 0.39), jet qualitative features in long-axis views (0.87 and 0.26), jet VTI (0.87 and 0.04) and PHT (0.73 and 0.10). Similar results were found in intra-observer comparisons. A 2-step granular approach combining the most reproducible parameters was used to grade PVL by the four observers. Inter-observer agreement was achieved in 86 % of cases (κ = 0.79). Combining color Doppler and continuous wave Doppler parameters in a granular algorithm yields excellent reproducibility of PVL assessment by TTE.

Sex-related differences in left ventricular remodeling in severe aortic stenosis and reverse remodeling after aortic valve replacement: A cardiovascular magnetic resonance study

BACKGROUND

Cardiac adaptation to aortic stenosis (AS) appears to differ according to sex, but reverse remodeling after aortic valve replacement has not been extensively described. The aim of the study was to determine using cardiac magnetic resonance imaging whether any sex-related differences exist in AS in terms of left ventricular (LV) remodeling, myocardial fibrosis, and reverse remodeling after valve replacement.

METHODS

One hundred patients (men, n = 60) with severe AS undergoing either transcatheter or surgical aortic valve replacement underwent cardiac magnetic resonance scans at baseline and 6 months after valve replacement.

RESULTS

Despite similar baseline comorbidity and severity of AS, women had a lower indexed LV mass than did men (65.3 ± 18.4 vs 81.5 ± 21.3 g/m(2), P < .001) and a smaller indexed LV end-diastolic volume (87.3 ± 17.5 vs 101.2 ± 28.6 mL/m(2), P = .002) with a similar LV ejection fraction (58.6% ± 10.2% vs 54.8% ± 12.9%, P = .178). Total myocardial fibrosis mass was similar between sexes (2.3 ± 4.1 vs 1.3 ± 1.1 g, P = .714), albeit with a differing distribution according to sex. After aortic valve replacement, men had more absolute LV mass regression than did women (18.3 ± 10.6 vs 12.7 ± 8.8 g/m(2), P = .007). When expressed as a percentage reduction of baseline indexed LV mass, mass regression was similar between the sexes (men 21.7% ± 10.1% vs women 18.4% ± 11.0%, P = .121). There was no sex-related difference in postprocedural LV ejection fraction or aortic regurgitation. Sex was not found to be a predictor of LV reverse remodeling on multiple regression analysis.

CONCLUSIONS

There are significant differences in the way that male and female hearts adapt to AS. Six months after aortic valve replacement, there are no sex-related differences in reverse remodeling, but superior reverse remodeling in men as a result of their more adverse remodeling profile at baseline.

Transcatheter Aortic Valve Implantation in Lower-Risk Patients With Aortic Stenosis

Transcatheter aortic valve implantation underwent progressive improvements until it became the default therapy for inoperable patients, and a recommended therapy in high-risk operable patients with symptomatic severe aortic stenosis. In the lower-risk patient strata, a currently costly therapy that still has important complications with questionable durability is competing with the established effective and still-improving surgical replacement. This report tries to weigh the clinical evidence, the recent technical improvements, the durability, and the cost-effectiveness claims supporting the adoption of transcatheter aortic valve implantation in intermediate-low risk patients. The importance of appropriate patients’ risk stratification and a more comprehensive approach to estimate that risk are also emphasized in the present report.

Regression of Paravalvular Aortic Regurgitation and Remodeling of Self-Expanding Transcatheter Aortic Valve: An Observation From the CoreValve U.S. Pivotal Trial

OBJECTIVES

The aim of this study was to describe the natural history and clinical importance of paravalvular aortic regurgitation (PVAR) after CoreValve transcatheter aortic valve replacement (TAVR) and to relate these findings to the structural and hemodynamic changes documented by serial echocardiographic analysis.

BACKGROUND

PVAR after TAVR with the self-expanding CoreValve bioprosthesis has been shown to regress over time, but the time course and the mechanism of PVAR regression has not been completely characterized.

METHODS

Patients with severe aortic stenosis who underwent CoreValve TAVR and followed up to 1 year in the multicenter CoreValve U.S. Pivotal Trial (Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement) were studied. Serial echocardiography studies were analyzed by an echocardiographic core laboratory. Annular sizing ratio was calculated from computed tomography measurements. Paired, as well as total, data were compared.

RESULTS

The CoreValve was implanted in 634 patients with a mean age of 82.7 ± 8.4 years. After a marked improvement noted at discharge, aortic valve velocity, mean gradient, and effective orifice area further improved significantly at 1 month (2.08 ± 0.45 m/s vs. 1.99 ± 0.46 m/s, p < 0.0001, 9.7 ± 4.4 mm Hg vs. 8.9 ± 4.6 mm Hg, p < 0.0001, and 1.78 ± 0.51 cm(2) vs. 1.85 ± 0.58 cm(2), p = 0.03, respectively). The improvement was sustained through 1 year. PVAR was moderate or severe in 9.9%, and of 36 patients with moderate PVAR at discharge and paired data, 30 (83%) improved at least 1 grade of regurgitation at 1 year. Annular sizing ratio was significantly associated with the degree of PVAR.

CONCLUSIONS

There was further improvement in aortic prosthetic valve hemodynamics and regression of PVAR up to 1 year compared with discharge after TAVR with CoreValve. These changes are possibly due to remodeling and outward expansion of the self-expandable CoreValve with nitinol frame. (Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement [Medtronic CoreValve U.S. Pivotal Trial]; NCT01240902).

Assessment of Paravalvular Regurgitation Following Transcatheter Aortic Valve Replacement

Paravalvular regurgitation (PVR) following transcatheter aortic valve replacement is a known complication associated with poorer outcomes. This article discusses the current techniques for assessing the severity of PVR, including angiography, hemodynamics, MRI, and echocardiography. The strengths and pitfalls of each modality are reviewed.

The role of cardiovascular magnetic resonance in stratifying paravalvular leak severity after transcatheter aortic valve replacement: an observational outcome study

BACKGROUND

Significant paravalvular leak (PVL) after transcatheter aortic valve replacement (TAVR) confers a worse prognosis. Symptoms related to significant PVL may be difficult to differentiate from those related to other causes of heart failure. Cardiovascular magnetic resonance (CMR) directly quantifies valvular regurgitation, but has not been extensively studied in symptomatic post-TAVR patients.

METHODS

CMR was compared to qualitative (QE) and semi-quantitative echocardiography (SQE) for classifying PVL and prognostic value at one year post-imaging in 23 symptomatic post-TAVR patients. The primary outcome was a composite of all-cause death, heart failure hospitalization, and intractable symptoms necessitating repeat invasive therapy; the secondary outcome was a composite of all-cause death and heart failure hospitalization. The difference in event-free survival according to greater than mild PVL versus mild or less PVL by QE, SQE, and CMR were evaluated by Kaplan-Meier survival analysis.

RESULTS

Compared to QE, CMR reclassified PVL severity in 48% of patients, with most patients (31%) reclassified to at least one grade higher. Compared to SQE, CMR reclassified PVL severity in 57% of patients, all being reclassified to at least one grade lower; SQE overestimated PVL severity (mean grade 2.5 versus 1.7, p=0.001). The primary and secondary outcomes occurred in 48% and 35% of patients, respectively. Greater than mild PVL by CMR was associated with reduced event-free survival for the primary outcome (p<0.0001), however greater than mild PVL by QE and SQE were not (p=0.83 and p=0.068). Greater than mild PVL by CMR was associated with reduced event-free survival for the secondary outcome, as well (p=0.012).

CONCLUSION

In symptomatic post-TAVR patients, CMR commonly reclassifies PVL grade compared with QE and SQE. CMR provides superior prognostic value compared to QE and SQE, as patients with greater than mild PVL by CMR (RF>20%) had a higher incidence of adverse events.

Determinants of clinical improvement after surgical replacement or transcatheter aortic valve implantation for isolated aortic stenosis

Background

Transcatheter aortic valve implantation (TAVI) is an alternative to surgical aortic valve replacement (SAVR) in patients with aortic stenosis (AS) and high surgical risk. Hemodynamic performance after TAVI is superior, but the impact of reverse remodeling on clinical improvement is controversial. We aim to address the differences in hemodynamic changes between SAVR and TAVI, and its correlation with LV remodeling and clinical improvement at 6 months follow-up.

Methods

Forty-two patients treated by TAVI were compared with 45 SAVR patients with a stented bioprosthesis. Clinical, 2D and 3D echocardiographic data were prospectively obtained before and six months after intervention.

Results

Patients had similar distribution for sex, body surface area and AS severity. TAVI patients were older, more symptomatic and had more comorbidities. They also had higher LV filling pressures, larger 3D indexed left atrium volume, but similar 3D indexed LV mass. At 6 months, TAVI patients had greater clinical improvement and higher effective orifice area index (EAOI), but only SAVR patients already had a significant decrease in 3D indexed LV mass and diastolic volume. In univariate analysis older age, NYHA class ≥ III, increase in EAOI and TAVI were related with functional class improvement. After multivariate analysis only NYHA class ≥ III (OR 8.81, CI:2.13-36.52; p = 0.003) and an increase in EAOI ≥ 105% (OR 3.87, CI:1.02-14.70; p = 0.04) were predictors of clinical improvement.

Conclusions

At 6 months, functional class improvement was greater after TAVI. Higher initial NYHA class and an increase in EAOI ≥ 105% were independently associated with functional enhancement. It is debatable if left ventricular remodeling is determinant for functional class improvement.

Electronic supplementary material

The online version of this article (doi:10.1186/1476-7120-12-41) contains supplementary material, which is available to authorized users.

Predictors of 1-year mortality in patients with aortic regurgitation after transcatheter aortic valve implantation: an analysis from the multicentre German TAVI registry

OBJECTIVE

Residual aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) has been associated with increased mortality. Nevertheless, a considerable proportion of these patients survives and appears to tolerate AR. Identification of patients at higher risk of death may assist in tailoring therapy, but predictors of mortality in this subset of patients is largely unknown.

METHODS

A total of 1432 patients were included in the German TAVI registry. One-year follow-up data were available for 1318 patients (92%). Of the latter, 201 patients (15.2%) had more-than-mild AR as evaluated by angiography and represent the population of the current analysis. Among these patients, baseline demographic, clinical, echocardiographic and angiographic characteristics were compared among survivors and non-survivors to identify factors associated with mortality at 1 year.

RESULTS

Mean age was 81.2±6.6 years and men represented 55%. The mean logistic EuroSCORE was 22±15%. Overall, 92% of patients received the Medtronic CoreValve and 8% received the Edwards Sapien valve. At 1 year, 61 patients (31%) with more-than-mild post-TAVI AR had died. Compared with patients who survived, patients who died had more commonly coronary artery disease, peripheral arterial disease and chronic renal impairment. Patients who died had a lower baseline LVEF (44±18% vs 52±16%, p=0.002), higher prevalence of more-than-mild (≥2+) mitral regurgitation (44% vs 27%, p=0.001), and a higher systolic pulmonary artery pressure (51±18 mm Hg vs 44±19 mm Hg, p=0.002), but the severity of aortic stenosis was similar, and the prevalence and severity of pre-TAVI AR was comparable (any AR in 88% vs 83%, respectively, p=0.29). Using Cox regression analysis, only baseline mitral regurgitation ≥2+ (HR 1.77, 95% CI 1.05 to 2.99, p=0.03) and systolic pulmonary artery pressure (HR 1.15, 95% CI 1.01 to 1.33, p=0.04) were independently associated with 1-year mortality, while female gender was protective (HR 0.54, 95% CI 0.30 to 0.96, p=0.03).

CONCLUSIONS

We identified preprocedural characteristics associated with 1-year mortality in patients with more-than-mild AR after TAVI. More-than-mild baseline mitral regurgitation, higher systolic pulmonary artery pressure and male gender were independently associated with worse outcome.