Lifetime Management of Aortic Stenosis: Transcatheter Versus Surgical Treatment for Young and Low-Risk Patients

Transcatheter aortic valve replacement is now indicated across all risk categories of patients with symptomatic severe aortic stenosis and has been proposed as first line option for the majority of patients >74 years old. However, median age of patients enrolled in the transcatheter aortic valve replacement low-risk trials is 74 years and transcatheter aortic valve replacement has never been systematically investigated in young low risk patients. Although the long-term data in surgical aortic valve replacement in young patients (age <75) are well known, such data remain lacking in transcatheter aortic valve replacement. In the absence of clear guideline recommendations in patients with challenging anatomies (eg, hostile calcium, bicuspid), it is important to know the potential advantages and disadvantages of each treatment and to consider how they might integrate with each other in the lifetime management of such patients. In this review, we discuss current outstanding issues on the management of severe aortic stenosis from a lifetime management perspective, particularly in terms of initial intervention and future reinterventions.

Clinical outcomes in patients with bicuspid aortic valves and ascending aorta dilatation equal or above 50mm

Background

Little is known about clinical outcomes in patients with bicuspid aortic valve (BAV) and ascending aortic diameters ≥50 mm where the elective surgical-indication zone begins.

Purpose

To assess incident aortic dissection (AoD), post-surgical survival and guideline implementation.

Methods

Multi-center retrospective study of BAV patients (≥18 years) with maximal root or tubular-ascending aortic diameters ≥50mm detected by transthoracic echocardiography at baseline. Ascertainment of aortic surgery, AoD and death was carried-out at their respective institutions. The primary outcome was AoD: “confirmed” AoD by surgery or death certificate, or “possible” AoD defined as sudden cardiac death of unknown cause by death certificate. Secondary outcomes were aortic surgery, post-surgical survival and guideline implementation.

Results

We included 506 consecutive BAV patients, mean age 61±14 years, 83% men, mean maximal aortic diameter 52±2 mm at baseline, ascending aorta was the most common segment ≥50mm (85%). During a median follow-up of 7.7 years, 356 (71%) underwent elective surgery (89% of class 1 patients). Early-surgery (≤6 months from baseline) occurred in 195 patients and 311 patients remained “under-surveillance”. Surgery under-surveillance (&gt;6 months from baseline) occurred in 161/311 (52%) patients at 2.6 [IQR: 1.5–4.7] years of follow-up. Surgical mortality was 1.4%. Ten-year post-surgical survival was &gt;90% and similar between early-surgery and surgery under-surveillance (p=0.8). Of 8 AoD events, 3 confirmed and 5 possible (all occurring in unoperated patients under-surveillance), 5 events occurred with maximal aortic baseline diameter ≥55 mm and/or &gt;1 year without clinical follow-up; therefore, under guideline non-compliance. Incidence of confirmed plus possible aortic dissection was 0.37% per year with size 50–54mm, 1.13% per year between 55–59mm, and 10.41% per year with size ≥60mm. Aortic stenosis was associated with AoD (p=0.04) and all-cause death in unoperated patients (p=0.001).

Conclusions

Our results suggest that BAV patients can be safely followed as per guidelines after aortic diameters enter the elective surgical zone (≥50mm), with excellent post-surgical survival regardless of whether surgery is early- or under-surveillance. Appropriate guideline implementation for surgical thresholds and interval clinical follow-up could have prevented most AoD events. Valvular disease guideline should also be followed to prevent AoD and improve survival in these patients.

Funding Acknowledgement

Type of funding sources: None.

Deformation of Transcatheter Aortic Valve Prostheses: Implications for Hypoattenuating Leaflet Thickening and Clinical Outcomes

BACKGROUND

Although transcatheter aortic valve replacement (TAVR) therapy continues to grow, there have been concerns about the occurrence of hypoattenuating leaflet thickening (HALT), which may affect prosthesis function or durability. This study aimed to examine prosthesis frame factors and correlate their extent to the frequency of HALT and clinical outcomes.

METHODS

We prospectively examined 565 patients with cardiac computed tomography screening for HALT at 30 days after balloon-expandable SAPIEN3 and self-expanding EVOLUT TAVR. Deformation of the TAVR prostheses, asymmetric prosthesis leaflet expansion, prosthesis sinus volumes, and commissural alignment were analyzed on the postprocedural computed tomography. For descriptive purposes, an index of prosthesis deformation was calculated, with values >1.00 representing relative midsegment underexpansion. A time-to-event model was performed to evaluate the association of HALT with the clinical outcome.

RESULTS

Overall, HALT was present in 21% of SAPIEN3 patients and in 16% of EVOLUT patients at 30 days after TAVR. The occurrence of HALT was directly associated with greater prosthesis frame deformation (P<0.001), worse asymmetry of the leaflets (P<0.001), and smaller TAVR neosinus volumes (P<0.001). These relations were present in both prosthetic types and in all of their size ranges (all P<0.05). In multivariable analyses that include clinical variables previously associated with HALT (eg, anticoagulant therapy), variables of TAVR prosthesis deformation remained predictive of HALT. Although HALT was not associated with changes in prosthetic hemodynamics, its presence was associated with the risk of mortality at 1 year, with respect to greater incidences of all-cause mortality (hazard ratio, 2.98 [95% CI, 1.57-5.63]; P=0.001), cardiac death (hazard ratio, 4.58 [95% CI, 1.81-11.6]; P=0.001), and a composite outcome of all-cause mortality and heart failure hospitalization (hazard ratio, 1.94 [95% CI, 1.14-3.30]; P=0.02) with adjustment for age, sex, and comorbidities.

CONCLUSIONS

Nonuniform expansion of TAVR prostheses resulting in frame deformation, asymmetric leaflet, and smaller neosinus volume is related to occurrence of HALT in patients who undergo TAVR. These data may have implications for both prosthesis valve design and deployment techniques to improve clinical outcomes for these patients.

Comparison Between Bicuspid and Tricuspid Aortic Regurgitation

Background

Although the Asian population is growing globally, data in Asian subjects regarding differences between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) in aortic regurgitation (AR) remain unexplored.

Objectives

The aim of this study was to examine differences between Asian BAV-AR and TAV-AR in significant AR, including aorta complications.

Methods

The study included 711 consecutive patients with chronic moderate to severe and severe AR from 2008 to 2020. Outcomes included all-cause death, aortic valve surgery (AVS), and incidence of aortic dissection (AD).

Results

There were 149 BAV-AR (mean age: 48 ± 16 years) and 562 TAV-AR (mean age: 68 ± 15 years; P < 0.0001) patients; baseline indexed left ventricle and indexed aorta size were larger in TAV-AR. Total follow-up was 4.8 years (IQR: 2.0-8.4 years), 252 underwent AVS, and 185 died during follow-up; 18 cases (only 1 BAV) of AD occurred, with a mean maximal aorta size of 60 ± 9 mm. The 10-year AVS incidence was higher in TAV-AR (51% ± 4%) vs BAV-AR (40% ± 5%) even after adjustment for covariates (P < 0.0001). The 10-year survival was higher in BAV-AR (86% ± 4%) vs TAV-AR (57% ± 3%; P < 0.0001) and became insignificant after age adjustment (P = 0.33). Post-AVS 10-year survival was 93% ± 5% in BAV-AR and 78% ± 5% in TAV-AR, respectively (P = 0.08). The 10-year incidence of AD was higher in TAV-AR (4.8% ± 1.5%) than in BAV-AR (0.9% ± 0.9%) and was determined by aorta size ≥45 mm (P ≤ 0.015). Compared with an age- and sex-matched population in Taiwan, TAV-AR (HR: 3.1) had reduced survival (P < 0.0001).

Conclusions

Our findings suggest that TAV-AR patients were at a later stage of AR course and had a high AD rate as opposed to BAV-AR patients in Taiwan, emphasizing the importance of early referral for timely management. Surgery on the aorta with a lower threshold in TAV-AR should be considered.

Association of Left Ventricular Remodeling Assessment by Cardiac Magnetic Resonance With Outcomes in Patients With Chronic Aortic Regurgitation

Importance

Chronic aortic regurgitation (AR) causes left ventricular (LV) volume overload, which results in progressive LV remodeling negatively affecting outcomes. Whether cardiac magnetic resonance (CMR) volumetric quantification can provide incremental risk stratification over standard clinical and echocardiographic evaluation in patients with chronic moderate or severe AR is unknown.

Objective

To compare LV remodeling measurements by CMR and echocardiography between patients with and without heart failure symptoms and to verify the association of remodeling measurements of patients with chronic moderate or severe AR but no or minimal symptoms with clinical outcomes receiving medical management.

Design, Setting, and Participants

This multicenter retrospective cohort study included consecutive patients with at least moderate chronic native AR evaluated by 2-dimensional transthoracic echocardiography and CMR examination within 90 days from each other between January 2012 and February 2020 at Allina Health System. Data were analyzed from June 2021 to January 2022.

Exposures

Clinical evaluation and risk stratification by CMR.

Main Outcomes and Measures

The end point was a composite of death, heart failure hospitalization, or progression of New York Heart Association functional class while receiving medical management, censoring patients at the time of aortic valve replacement (when performed) or at the end of follow-up.

Results

Of the 178 included patients, 119 (66.9%) were male, 158 (88.8%) presented with no or minimal symptoms (New York Heart Association class I or II), and the median (IQR) age was 58 (44-69) years. Compared with patients with no or minimal symptoms, symptomatic patients had greater LV end-systolic volume index (LVESVi) by CMR (median [IQR], 66 [46-85] mL/m2 vs 42 [30-58] mL/m2; P < .001), while there were no significant differences by echocardiography (LVESVi: median [IQR], 38 [30-58] mL/m2 vs 27 [20-42] mL/m2; P = .07; LV end-systolic diameter index: median [IQR], 21 [17-25] mm/m2 vs 18 [15-22] mm/m2; P = .17). During the median (IQR) follow-up of 3.3 (1.6-5.8) years, 50 patients with no or minimal symptoms receiving medical management developed the composite end point, which, in multivariate analysis adjusted for age and EuroSCORE II, was independently associated with LVESVi of 45 mL/m2 or greater and aortic regurgitant fraction of 32% or greater, the latter adding incremental prognostic value to CMR volumetric assessment.

Conclusions and Relevance

In patients with chronic moderate or severe AR, patients presenting with heart failure symptoms have greater LVESVi by CMR than those with no or minimal symptoms. In patients with no or minimal symptoms, CMR quantification of LVESVi and AR severity may identify those at risk of death or incident heart failure and therefore should be considered in the clinical evaluation and decision-making of these patients.

Coaptation Reserve Predicts Optimal Reduction in Mitral Regurgitation and Long-Term Survival With Transcatheter Edge-to-Edge Repair

BACKGROUND

Although transcatheter edge-to-edge repair (TEER) is effective and safe, there is a need for better prediction of optimal outcomes. We aimed to determine predictors of optimal reduction in mitral regurgitation (MR) and survival with TEER.

METHODS

We examined mitral anatomy and its change with TEER on outcomes in 183 patients (age, 82 [77-87] years; 53% women). Coaptation reserve was measured as the distance of continuous apposition of the A2 and P2 leaflet segments in 2-dimensional apical long-axis imaging at the site of the predominant jet of MR. Augmentation in coaptation was measured as the total amount of leaflet insertion. Addressable coaptation area was calculated using the physical boundaries of the TEER device.

RESULTS

Coaptation reserve, its augmentation, and addressable coaptation area were strong predictors of MR reduction (all P<0.001), as well as heart failure hospitalization and death. For patients with either mild or no residual MR, median values for coaptation reserve, its augmentation, and addressable coaptation area were 3.7 (2.8-4.5) mm, 7.3 (5.2-9.5) mm, and 59.0 (48.0-71.8) mm2, respectively. Receiver operating characteristic analyses determined the best values for optimal MR reduction as a coaptation reserve of >3.0 mm (P<0.001), addressable coaptation area of ≥52 mm2 (P<0.001), and coaptation augmentation of ≥4.7 mm (P<0.001). These values were associated with greater 2-year survival free of all-cause mortality and persisting even in analyses restricted to those with mild or no residual MR after TEER.

CONCLUSIONS

Coaptation reserve and its augmentation are simple, independent parameters that predict optimal MR reduction and better survival in patients undergoing TEER. These findings may have implications for patient selection and expanded use of the therapy.

Computed Tomography Planning for Transcatheter Mitral Valve Replacement

Transcatheter mitral valve replacement (TMVR) is a rapidly evolving treatment for mitral regurgitation. As with transcatheter aortic valve replacement, multidetector computed tomography analysis plays a central role in defining the candidacy, device selection and safety for TMVR procedures. This contemporary review will describe in detail the multidetector computed tomography data collection, analysis, and planning for TMVR procedures in patients with native mitral regurgitation as well as in those with failed surgical prosthetic mitral valve replacement or surgical mitral valve repair.

Automated Global Longitudinal Strain Exhibits a Robust Association with Death in Asymptomatic Chronic Aortic Regurgitation

BACKGROUND

Whether automated left ventricular global longitudinal strain (LVGLS) is associated with outcomes in asymptomatic aortic regurgitation (AR) is unknown.

OBJECTIVE

To explore the impact of automated LVGLS on survival and compare it with conventional LV parameters in chronic asymptomatic AR.

METHODS

LVGLS (presented as absolute value) was measured using fully-automated two-dimensional strain software in consecutive patients with isolated chronic ≥moderate-severe AR between 2004 and 2020; incremental value of LVGLS was assessed. Limited correction of endocardial border tracking was performed if needed.

RESULTS

Of 550 asymptomatic patients (age 60±17 years; 86% men), average LVGLS was 17±3% (1^st and 2^nd tertile, 15.8% and 18.5%). In 16% cases, tracking border was partially corrected; average time for analysis was 25±5 seconds. At a median (interquartile range) of 4.8(1.5-9.9) years, 87 patients had died (19 died after aortic-valve surgery [AVS]). Separate multivariable models adjusted for age, sex, Charlson index, AR severity and time-dependent AVS demonstrated that LVEF(hazard ratio[HR] per 10%: 0.9), LV end-systolic volume index(LVESVi; HR per 5ml/m²: 1.08) and LVGLS(HR per unit: 0.87) were independently associated with death(all p≤0.018); however, LVGLS remained statistically significant (HR: 0.86-0.9; P≤0.007) as compared head-to-head to LVEF, LVESVi and LV end-systolic dimension index(LVESDi). The association of LVGLS and mortality was consistent across all subgroups (P for interaction all≥0.08). Spline curves showed that continuous risk of death rose at LVGLS <15%. Those with LVGLS <15% had 2.6-fold risk of death [95% CI 1.54-4.23] while those with LVGLS <15% plus LVESVi≥45ml/m² had 3.96-fold risk[95% CI 1.94-8.03].

CONCLUSION

In this large cohort of asymptomatic patients with ≥moderate-severe AR, automated LVGLS was feasible, efficient, and independently associated with death on head-to-head comparison with conventional LVEF, LVESDi, and LVESVi. The automated-LVGLS threshold of <15% alone or combined with LVESVi≥45ml/m², was significantly associated with increased mortality risk and may be considered in early surgery decision-making.

Genome-wide association study reveals novel genetic loci: a new polygenic risk score for mitral valve prolapse

AIMS

Mitral valve prolapse (MVP) is a common valvular heart disease with a prevalence of >2% in the general adult population. Despite this high incidence, there is a limited understanding of the molecular mechanism of this disease, and no medical therapy is available for this disease. We aimed to elucidate the genetic basis of MVP in order to better understand this complex disorder.

METHODS AND RESULTS

We performed a meta-analysis of six genome-wide association studies that included 4884 cases and 434 649 controls. We identified 14 loci associated with MVP in our primary analysis and 2 additional loci associated with a subset of the samples that additionally underwent mitral valve surgery. Integration of epigenetic, transcriptional, and proteomic data identified candidate MVP genes including LMCD1, SPTBN1, LTBP2, TGFB2, NMB, and ALPK3. We created a polygenic risk score (PRS) for MVP and showed an improved MVP risk prediction beyond age, sex, and clinical risk factors.

CONCLUSION

We identified 14 genetic loci that are associated with MVP. Multiple analyses identified candidate genes including two transforming growth factor-β signalling molecules and spectrin β. We present the first PRS for MVP that could eventually aid risk stratification of patients for MVP screening in a clinical setting. These findings advance our understanding of this common valvular heart disease and may reveal novel therapeutic targets for intervention.

Arrhythmias in Patients With Valvular Heart Disease: Gaps in Knowledge and the Way Forward

The prevalence of both organic valvular heart disease (VHD) and cardiac arrhythmias is high in the general population, and their coexistence is common. Both VHD and arrhythmias in the elderly lead to an elevated risk of hospitalization and use of health services. However, the relationships of the two conditions is not fully understood and our understanding of their coexistence in terms of contemporary management and prognosis is still limited. VHD-induced left ventricular dysfunction/hypertrophy and left atrial dilation lead to both atrial and ventricular arrhythmias. On the other hand, arrhythmias can be considered as an independent condition resulting from a coexisting ischemic or non-ischemic substrate or idiopathic ectopy. Both atrial and ventricular VHD-induced arrhythmias may contribute to clinical worsening and be a turning point in the natural history of VHD. Symptoms developed in patients with VHD are not specific and may be attributable to hemodynamical consequences of valve disease but also to other cardiac conditions including arrhythmias which are notably prevalent in this population. The issue how to distinguish symptoms related to VHD from those related to atrial fibrillation (AF) during decision making process remains challenging. Moreover, AF is a traditional limit of echocardiography and an important source of errors in assessment of the severity of VHD. Despite recent progress in understanding the pathophysiology and prognosis of postoperative AF, many questions remain regarding its prevention and management. Furthermore, life-threatening ventricular arrhythmias can predispose patients with VHD to sudden cardiac death. Evidence for a putative link between arrhythmias and outcome in VHD is growing but available data on targeted therapies for VHD-related arrhythmias, including monitoring and catheter ablation, is scarce. Despite growing evidences, more research focused on the prognosis and optimal management of VHD-related arrhythmias is still required. We aimed to review the current evidence and identify gaps in knowledge about the prevalence, prognostic considerations, and treatment of atrial and ventricular arrhythmias in common subtypes of organic VHD.