Impact of new-onset arrhythmia on cardiac reverse remodeling following transcatheter aortic valve replacement: computed tomography-derived left ventricular and atrial strains

OBJECTIVE

Patients who undergo transcatheter aortic valve replacement (TAVR) are at risk for new-onset arrhythmia (NOA) that may require permanent pacemaker (PPM) implantation, resulting in decreased cardiac function. We aimed to investigate the factors that are associated with NOA after TAVR and to compare pre- and post-TAVR cardiac functions between patients with and without NOA using CT-derived strain analyses.

METHODS

We included consecutive patients who underwent pre- and post-TAVR cardiac CT scans six months after TAVR. New-onset left bundle branch block, atrioventricular block, and atrial fibrillation/flutter lasting over 30 days after the procedure and/or the need for PPM diagnosed within 1 year after TAVR were regarded as NOA. Implant depth and left heart function and strains were analyzed using multi-phase CT images and compared between patients with and without NOA.

RESULTS

Of 211 patients (41.7% men; median 81 years), 52 (24.6%) presented with NOA after TAVR, and 24 (11.4%) implanted PPM. Implant depth was significantly deeper in the NOA group than in the non-NOA group (- 6.7 ± 2.4 vs. - 5.6 ± 2.6 mm; p = 0.009). Left ventricular global longitudinal strain (LV GLS) and left atrial (LA) reservoir strain were significantly improved only in the non-NOA group (LV GLS,  - 15.5 ± 4.0 to  - 17.3 ± 2.9%; p < 0.001; LA reservoir strain, 22.3 ± 8.9 to 26.5 ± 7.6%; p < 0.001). The mean percent change of the LV GLS and LA reservoir strains was evident in the non-NOA group (p = 0.019 and p = 0.035, respectively).

CONCLUSIONS

A quarter of patients presented with NOA after TAVR. Deep implant depth on post-TAVR CT scans was associated with NOA. Patients with NOA after TAVR had impaired LV reserve remodeling assessed by CT-derived strains.

CLINICAL RELEVANCE STATEMENT

New-onset arrhythmia (NOA) following transcatheter aortic valve replacement (TAVR) impairs cardiac reverse remodeling. CT-derived strain analysis reveals that patients with NOA do not show improvement in left heart function and strains, highlighting the importance of managing NOA for optimal outcomes.

KEY POINTS

• New-onset arrhythmia following transcatheter aortic valve replacement (TAVR) is a concern that interferes with cardiac reverse remodeling. • Comparison of pre-and post-TAVR CT-derived left heart strain provides insight into the impaired cardiac reverse remodeling in patients with new-onset arrhythmia following TAVR. • The expected reverse remodeling was not observed in patients with new-onset arrhythmia following TAVR, given that CT-derived left heart function and strains did not improve.

Transcatheter Aortic Valve Implantation: Addressing the Subsequent Risk of Permanent Pacemaker Implantation

Transcatheter aortic valve implantation (TAVI) is now a commonly used therapy in patients with severe aortic stenosis, even in those patients at low surgical risk. The indications for TAVI have broadened as the therapy has proven to be safe and effective. Most challenges associated with TAVI after its initial introduction have been impressively reduced; however, the possible need for post-TAVI permanent pacemaker implantation (PPI) secondary to conduction disturbances continues to be on the radar. Conduction abnormalities post-TAVI are always of concern given that the aortic valve lies in close proximity to critical components of the cardiac conduction system. This review will present a summary of noteworthy pre-and post-procedural conduction blocks, the best use of telemetry and ambulatory device monitoring to avoid unnecessary PPI or to recognize the need for late PPI due to delayed high-grade conduction blocks, predictors to identify those patients at greatest risk of requiring PPI, important CT measurements and considerations to optimize TAVI planning, and the utility of the MInimizing Depth According to the membranous Septum (MIDAS) technique and the cusp-overlap technique. It is stressed that careful membranous septal (MS) length measurement by MDCT during pre-TAVI planning is necessary to establish the optimal implantation depth before the procedure to reduce the risk of compression of the MS and consequent damage to the cardiac conduction system.

Pacing-Related Differences After SAPIEN-3 TAVI: Clinical and Echocardiographic Correlates

Data regarding the impact of pacing on outcomes after transcatheter aortic valve implantation (TAVI) is evolving especially with regards to pre-existing permanent pacemaker (PPM). We examined the impact of new and previous PPM on the clinical and hemodynamic outcomes after SAPIEN-3 TAVI. We included all consecutive patients who underwent transfemoral TAVI using SAPIEN-3 valve from 2015 to 2018 at our institution. Among 1,028 patients, 10.2% required a new PPM within 30 days, whereas 14% had a pre-existing PPM. The presence of either previous or new PPM had no impact on the 3-year mortality (log-rank p = 0.6) or 1-year major adverse cardiac and cerebrovascular events (log-rank p = 0.65). New PPM was associated with lower left ventricular (LV) ejection fraction (LVEF) at both 30 days (54.4 ± 11.3% vs 58.4 ± 10.1%, p = 0.001) and 1 year (54.2 ± 12% vs 59.1 ± 9.9%, p = 0.009) than no PPM. Similarly, previous PPM was associated with worse LVEF at 30 days (53.6 ± 12.3%, p <0.001) and 1 year (55.5 ± 12.1%, p = 0.006) than no PPM. Interestingly, new PPM was associated with lower 1-year mean gradient (11.4 ± 3.8 vs 12.6 ± 5.6 mm Hg, p = 0.04) and peak gradient (21.3 ± 6.5 vs 24.1 ± 10.4 mm Hg, p = 0.01), despite no baseline differences. Previous PPM was also associated with lower 1-year mean gradient (10.3 ± 4.4 mm Hg, p = 0.001) and peak gradient (19.4 ± 8 mm Hg, p <0.001) and higher Doppler velocity index (0.51 ± 0.12 vs 0.47 ± 0.13, p = 0.039). Moreover, 1-year LV end-systolic volume index was higher with new (23.2 ± 16.1 vs 20 ± 10.8 ml/m², p = 0.038) and previous PPM (24.5 ± 19.7, p = 0.038) than no PPM. Previous PPM was associated with higher moderate-to-severe tricuspid regurgitation (35.3% vs 17.7%, p <0.001). There were no differences regarding the rest of the studied echocardiographic outcomes at 1 year. In conclusion, new and previous PPM did not affect 3-year mortality or 1-year major adverse cardiac and cerebrovascular events; however, they were associated with worse LVEF, higher 1-year LV end-systolic volume index, and lower mean and peak gradients on follow-up than no PPM.

Right bundle branch block is not associated with worse short- and mid-term outcome after transcatheter aortic valve implantation

Background

Transcatheter aortic valve implantation (TAVI) is the standard treatment option for patients with severe aortic stenosis (AS) at intermediate or high surgical risk. Preexisting right bundle branch block (RBBB) is a strong predictor of new pacemaker implantation (PPM) after TAVI, and previous data indicate a worse short- and long-term outcome of patients. The aim of this study was to investigate whether preexisting RBBB has an effect on the short- and mid-term outcome of patients undergoing TAVI in a German high-volume TAVI center.

Methods

For the present retrospective analysis, a total of 1,891 patients with native severe AS with successful TAVI without preexisting PPM were included. The primary endpoint was all-cause mortality after 30 days and 12 months. Baseline RBBB was present in 190 (10.1%) of cases.

Results

Patients with preexisting RBBB had a considerably higher rate of new PPM after TAVI compared with patients without RBBB (87/190 [45.8%] vs. 219/1,701 [12.9%]; p<0.001). RBBB had no impact on all-cause mortality at 30 days (2.1% vs. 2.7%; p = 0.625) and at 12 months (14.4% vs. 13.6%; p = 0.765). Further stratification according to the presence of new PPM showed a difference in mid-term survival rates between the four groups, with the worst outcome for patients without RBBB and new PPM (log rank p = 0.024). However, no difference in mid-term cardiovascular survival was found.

Conclusion

Preexisting RBBB is a common finding in patients with severe AS undergoing TAVI and is associated with considerably higher PPM rates but not with worse short- and mid-term outcome.

Transcatheter aortic valve implantation in low-risk patients: A case of rational over exuberance. The time is not now

BACKGROUND

Review of evidence and concerns, relating to extension of transcatheter aortic valve implantation usage to low-risk patients.

METHODS

Comprehensive literature review was conducted identifying articles relating to transcatheter aortic valve implantation.

RESULTS

Transcatheter aortic valve implantation is effective in patients with aortic stenosis. Currently, long-term durability and cost-effectiveness are unproven, anticoagulation requirement undefined, permanent pacemaker implantation and paravalvular leak rates higher than following surgical aortic valve replacement.

CONCLUSIONS

Current evidence supporting transcatheter aortic valve implantation usage in low-risk patients is insufficient. Extending use now, to this large young patient population is premature, and should be delayed.

Predictors of pacemaker dependency in patients implanted with a pacemaker after Transaortic valve replacement

Introduction and objectives

The development of complete AV block and the need for pacemaker implantation (PM) is the most frequent complication after Transaortic valve replacement (TAVR). In other PM clinical contexts, a higher percentage of ventricular stimulation has been associated with worse prognosis. The objective was to study the existence of predictors of PM dependence.

Methods

We identified 96 consecutive patients who had received a PM post-TAVR (all Core-Valve). We retrospectively analyzed this cohort with the aim of identifying predictors of a high and very high percentage of ventricular pacing (VP), PM dependency and survival.

Results

The mean age was 82.3 years, with a mean logistic EuroSCORE of 17.1, 53% were women and 12% of patients had LVEF < 50%. The indication was complete AV block in 40.5%, and LBBB in 59.5%. Mean survival was 62.7 months, IQR [54.4-71]. The only independent predictor of mortality was the pre-TAVR logistic Euro-SCORE (RR = 1,026, p = 0.033), but not LVEF < 50%, VP > 50%, VP > 85% or PM dependence. In 73 patients PM rhythm was documented at the end of follow-up. Of these, 14 (19.2%) were considered dependent, and 37 (50.7%) presented VP > 50%. The post-TAVR complete AV block recovery rate was 67.8%. In multivariate analysis, female sex (HR = 5.6, p = 0.005), and indication of complete AV block vs. LBBB (HR = 15.7, p = 0.017) were independently associated with PM dependency.

Conclusions

Female sex and indication due to complete AV block were independent predictors of PM dependency during follow up. In our series of patients with mostly normal LVEF, a high percentage of stimulation does not influence prognosis.

Intraventricular Conduction Disturbances After Transcatheter Aortic Valve Implantation

Despite significant improvements in transcatheter aortic valve implantation (TAVI) outcomes, periprocedural conduction disturbances, such as new-onset left bundle branch block (LBBB) and new pacemaker implantation (PMI), remain relatively frequent concerns. The development of periprocedural conduction disturbances can be explained by the proximity between the aortic valve and the conduction system. Although prior studies reported heterogeneity in PMI rates after TAVI, current evidence supports the potentially deleterious consequence of LBBB and PMI, and several predisposing factors have been reported. Therefore, new strategies to avoid conduction disturbances and to improve their management are required, particularly with the current trend to expand TAVI to a low-risk population.

Pacemaker implantation after transcatheter aortic valve: why is this still happening?

During the past years, the industry and most transcatheter aortic valve operators have focused on reduction of paravalvular leaks rather than on the reduction of permanent pacemakers (PPM). However, since indication for transcatheter aortic valve implantation (TAVI) is moving toward a healthier and younger patient population, new PPMs may become more of an issue. Certain factors such as pre-existing conduction disorders or anatomical features cannot be changed. However, the amount of mechanical trauma to the conduction system and periprocedural medical management offers the potential for optimization. By optimizing our procedure, we may finally be able to achieve low, surgical-like, PPM rates.

Adverse effects of left ventricular electrical dyssynchrony on cardiac reverse remodeling and prognosis after aortic valve surgery

BACKGROUND

Electrical dyssynchrony (ED) is one of the important contributing mechanisms in the progression of heart failure. We hypothesized that ED would interfere with cardiac reverse remodeling and affect prognosis after aortic valve surgery.

METHODS

A total of 411 consecutive patients (233 males, mean age 65±11 years) who underwent aortic valve surgery were retrospectively analyzed. The patients were divided into two groups according to the presence of ED [Group 1: no ED (n=382, 93%), Group 2: ED (n=29, 7%)]. ED was defined as either left ventricular bundle branch block, or electrical pacing rhythm. Cardiac reverse remodeling was assessed at 1 year after surgery by the changes in left ventricular ejection fraction (LVEF), LV end-systolic volume (LVESV), and left atrial volume index (LAVI). The primary endpoint was a composite of hospitalization for heart failure, and all-cause mortality.

RESULTS

At 1 year after surgery, group 2 showed lower LVEF (58±15% vs. 64±9%, p=0.044), and higher LAVI (42±18ml/m² vs. 33±13ml/m², p=0.018) than group 1. However, LVESV values (55±38ml vs. 42±24ml, p=0.076) were not significantly different. In particular, in patients with reduced preoperative LVEF, the LVEF was markedly increased in group 1 but not in group 2 after 1 year. During a median follow-up of 39 months, group 2 showed a worse clinical outcome than group 1 (20.7% vs. 7.6%, p=0.031). After adjusting for confounding factors in the multivariate analyses, age [hazard ratio (HR) 1.11, 95% confidence interval (CI) 1.06-1.16, p<0.001] and the presence of ED (HR 2.43, 95% CI 1.01-5.89, p=0.046) were found to be independent predictors of clinical outcomes.

CONCLUSIONS

ED after aortic valve surgery negatively affected cardiac remodeling and prognosis.

Clinical and Echocardiographic Outcomes Following Permanent Pacemaker Implantation After Transcatheter Aortic Valve Replacement: Meta-Analysis and Meta-Regression

BACKGROUND

Transcatheter aortic valve replacement has become the procedure of choice for inoperable, high-risk, and many intermediate-risk patients with aortic stenosis. Conduction abnormalities are a common finding after transcatheter aortic valve replacement and often result in permanent pacemaker (PPM) implantation. Data pertaining to the clinical impact of PPM implantation are controversial. We used meta-analysis techniques to summarize the effect of PPM implantation on clinical and echocardiographic outcomes after transcatheter aortic valve replacement.

METHODS AND RESULTS

Data were summarized as Mantel-Haenszel relative risk (RR) and 95% confidence intervals (CIs) for dichotomous variables and as standardized mean difference and 95% CI for continuous variables We used the Higgins I² statistic to evaluate heterogeneity. We found that patients with and without PPM have similar all-cause mortality (RR, 0.85; 95% CI, 0.70-1.03), cardiovascular mortality (RR, 0.84; 95% CI, 0.59-1.18), myocardial infarction (RR, 0.47; 95% CI, 0.20-1.11), and stroke (RR, 1.26; 95% CI, 0.70-2.26) at 30 days. The groups were also comparable in all-cause mortality (RR, 1.03; 95% CI, 0.92-1.16), cardiovascular mortality (RR, 0.69; 95% CI, 0.39-1.24), myocardial infarction (RR, 0.58; 95% CI, 0.30-1.13), and stroke (RR, 0.70; 95% CI, 0.47-1.04) at 1 year. We observed that the improvement in left ventricular ejection fraction was significantly greater in the patients without PPM (standardized mean difference, 0.22; 95% CI, 0.12-0.32).

CONCLUSIONS

PPM implantation is not associated with increased risk of all-cause mortality, cardiovascular mortality, stroke, or myocardial infarction both at short- and long-term follow-up. However, PPM is associated with impaired left ventricular ejection fraction recovery post-transcatheter aortic valve replacement.

Permanent pacemaker insertion in patients with conduction abnormalities post transcatheter aortic valve replacement: a review and proposed guidelines

Conduction abnormalities are a common and serious complication of transcatheter aortic valve replacement (TAVR) with well-established predictive factors. Current guidelines are not concrete, leaving several questions unanswered about indications, timing and risks of pacemaker implantation post-TAVR. In this review article, we discuss current guidelines, predictors of pacemaker implantation, clinical implications of this procedure and our recommendations for reducing the pacemaker implantation rate post-TAVR.

Conduction Disturbances After Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR) has become a well-accepted option for treating patients with aortic stenosis at intermediate to high or prohibitive surgical risk. TAVR-related conduction disturbances, mainly new-onset left bundle-branch block and advanced atrioventricular block requiring permanent pacemaker implantation, remain the most common complication of this procedure. Furthermore, improvements in TAVR technology, akin to the increasing experience of operators/centers, have translated to a major reduction in periprocedural complications, yet the incidence of conduction disturbances has remained relatively high, with perhaps an increasing trend over time. Several factors have been associated with a heightened risk of conduction disturbances and permanent pacemaker implantation after TAVR, with prior right bundle-branch block and transcatheter valve type and implantation depth being the most commonly reported. New-onset left bundle-branch block and the need for permanent pacemaker implantation may have a significant detrimental association with patients’ prognosis. Consequently, strategies intended to reduce the risk and to improve the management of such complications are of paramount importance, particularly in an era when TAVR expansion toward treating lower-risk patients is considered inevitable. In this article, we review the available evidence on the incidence, predictive factors, and clinical association of conduction disturbances after TAVR and propose a strategy for the management of these complications.

Patient selection for TAVI in 2016: should we break through the low-risk barrier?

The earliest evidence supporting transcatheter aortic valve implantation (TAVI) was derived from its comparison with conservative therapy in inoperable patients and with surgical aortic valve replacement (SAVR) in extremely high risk patients. TAVI had a relative advantage in these situations being less invasive and hence less prone to the classic early postoperative devastating complications. To prove as effective in less fragile and less morbid patients, the long-term durability of the haemodynamic and clinical gains from TAVI needs to be confirmed. In this report we will discuss three aspects of the dilemma of expanding TAVI indications to lower-risk patients: first, available data on early and late outcomes after TAVI; second, durability issues; and third, TAVI complications and procedural refinements.

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.

Permanent pacemaker implantation after transcatheter aortic valve implantation: impact on late clinical outcomes and left ventricular function

BACKGROUND

Very few data exist on the clinical impact of permanent pacemaker implantation (PPI) after transcatheter aortic valve implantation. The objective of this study was to assess the impact of PPI after transcatheter aortic valve implantation on late outcomes in a large cohort of patients.

METHODS AND RESULTS

A total of 1556 consecutive patients without prior PPI undergoing transcatheter aortic valve implantation were included. Of them, 239 patients (15.4%) required a PPI within the first 30 days after transcatheter aortic valve implantation. At a mean follow-up of 22±17 months, no association was observed between the need for 30-day PPI and all-cause mortality (hazard ratio, 0.98; 95% confidence interval, 0.74-1.30; P=0.871), cardiovascular mortality (hazard ratio, 0.81; 95% confidence interval, 0.56-1.17; P=0.270), and all-cause mortality or rehospitalization for heart failure (hazard ratio, 1.00; 95% confidence interval, 0.77-1.30; P=0.980). A lower rate of unexpected (sudden or unknown) death was observed in patients with PPI (hazard ratio, 0.31; 95% confidence interval, 0.11-0.85; P=0.023). Patients with new PPI showed a poorer evolution of left ventricular ejection fraction over time (P=0.017), and new PPI was an independent predictor of left ventricular ejection fraction decrease at the 6- to 12-month follow-up (estimated coefficient, -2.26; 95% confidence interval, -4.07 to -0.44; P=0.013; R(2)=0.121).

CONCLUSIONS

The need for PPI was a frequent complication of transcatheter aortic valve implantation, but it was not associated with any increase in overall or cardiovascular death or rehospitalization for heart failure after a mean follow-up of ≈2 years. Indeed, 30-day PPI was a protective factor for the occurrence of unexpected (sudden or unknown) death. However, new PPI did have a negative effect on left ventricular function over time.

Targeting the renin-angiotensin-aldosterone system in heart failure

The renin-angiotensin-aldosterone system is a well-established therapeutic target in the treatment of heart failure (HF). Substantial advances have been made with existing agents--angiotensin-converting enzyme (ACE) inhibitors, angiotensin II-receptor blockers (ARBs), and mineralocorticoid-receptor antagonists (MRAs)--and new data continue to emerge. The indication for the use of MRAs has been broadened to include potentially all patients who have HF with reduced ejection fraction (HFrEF), and ACE inhibitors might have a novel application in patients who are at risk of left ventricular dysfunction (those with aortic valvular disease or pacing-induced heart disease). ARBs have been shown to be a beneficial alternative to ACE inhibitors in HFrEF, but their value when added to ACE inhibitors has been questioned. Upstream, direct renin blockade with aliskiren is being pursued in two large trials of HF, despite the premature halting of a third study. A substantial, unmet need remains in patients who have HF with preserved ejection fraction (HFpEF). New data on spironolactone and LCZ696 (a combined ARB and neprilysin inhibitor) show promise for these patients. Results of the TOPCAT study of spironolactone in patients with HFpEF are awaited, and LCZ696 is now being tested in a large trial in patients with HFrEF.

Renin-angiotensin system blockers are associated with reduced mortality and heart failure hospitalization in patients paced for complete atrioventricular block

BACKGROUND

Right ventricular apical pacing can cause dyssynchronous activation of the ventricles, increase sympathetic activation, cause abnormalities in myocardial perfusion, worsen cardiac output and endothelial function, and may be associated with adverse cardiovascular effects. The use of rennin-angiotensin system blockers (RASBs) may be beneficial in counteracting these potentially harmful effects of right ventricular pacing.

OBJECTIVE

To explore the impact of RASB use on the outcome in patients with right ventricular pacemakers implanted for complete atrioventricular (AV) block.

METHODS

Patients implanted with right ventricular pacemakers for complete AV block between 1994 and 2009 were identified from the Tayside Pacing Registry. Cox proportional hazards model was used to assess differences in all-cause mortality and congestive heart failure hospitalizations for those receiving RASB during follow-up, adjusted for confounding variables. We also performed 2 sensitivity analyses--a propensity score-matched analysis and time-dependent analyses--to minimize bias.

RESULTS

Eight hundred twenty patients (57% men; median age 73 years; range 22-103 years) received pacemakers for complete AV block between 1994 and 2008 (54% dual-chamber pacemaker and 46% ventricular demand pacemaker). Two hundred seventy-eight (34%) patients had received RASBs. Mean follow-up was 4.9 ± 4.6 years, with 540 (65%) deaths. RASB use was independently associated with significantly reduced mortality (adjusted hazard ratio 0.67; 95% confidence interval 0.47-0.94; P = .017) and reduced heart failure hospitalization (adjusted hazard ratio 0.42; 95% confidence interval 0.17-0.92; P <.001).

CONCLUSIONS

This study suggests that RASBs may confer outcome benefits in patients with right ventricular pacemakers implanted for complete AV block.