Does Surgical Ablation of Atrial Fibrillation Benefit Patients Undergoing Bioprosthetic Valve Replacement?

The impact of permanent pacemaker implantation on long-term survival after cardiac surgery: A systematic review and meta-analysis

OBJECTIVES

The long-term impact of permanent pacemaker (PPM) implantation on survival after cardiac surgery remains ill defined. We aimed to investigate the effect of PPM on survival and explore factors driving outcomes using meta-regression according to the type of surgery.

METHODS

MEDLINE, EMBASE, and the Cochrane Library Central Register of Controlled Trials were searched through October 2023 to identify studies reporting the long-term outcomes of PPM implantation. The primary outcome was all-cause mortality during follow-up. The secondary outcome was heart failure rehospitalization. The subgroup analysis and meta-regression analysis were performed according to the type of surgery.

RESULTS

A total of 28 studies met the inclusion criteria. 183,555 patients (n = 6298; PPM, n = 177,257; no PPM) were analyzed for all-cause mortality, with a weighted median follow-up of 79.7 months. PPM implantation was associated with increased risks of all-cause mortality during follow-up (hazard ratio, 1.22; confidence interval, 1.08-1.38, P < .01) and heart failure rehospitalization (hazard ratio, 1.24; confidence interval, 1.01-1.52, P = .04). Meta-regression demonstrated the adverse impact of PPM was less prominent in patients undergoing mitral or tricuspid valve surgery, whereas studies with a greater proportion with aortic valve replacement were associated with worse outcomes. Similarly, a greater proportion with atrioventricular block as an indication of PPM was associated with worse survival.

CONCLUSIONS

PPM implantation after cardiac surgery is associated with a greater risk of long-term all-cause mortality and heart failure rehospitalization. This impact is more prominent in patients undergoing aortic valve surgery or atrioventricular block as an indication than those undergoing mitral or tricuspid valve surgery.

The long-term influence of lesion set in the surgical ablation of atrial fibrillation during mitral valve surgery: Multicenter propensity-score weighted study

OBJECTIVE

This study aimed to assess the effect of the lesion sets for surgical ablation of atrial fibrillation on long-term outcomes and identify the optimal lesion set.

METHODS

Between 2005 and 2017, 1825 patients underwent surgical ablation concomitant to mitral valve surgery in the participating institutions. Of these, 529 underwent left atrial ablation, whereas the remainder had biatrial ablation. The clinical and rhythm outcomes were compared, considering death as a competing event. Inverse probability treatment weighting was used to mitigate the selection bias.

RESULTS

The patients undergoing left atrial ablation were younger and less frequently had long-standing atrial fibrillation with a shorter duration or required concomitant tricuspid valve surgery. Adjusted analysis showed that left atrial ablation was associated with a lower risk of early pacemaker implantation (odds ratio, 0.16; 95% CI, 0.07-0.38; P < .001) than biatrial ablation. Over a median follow-up of 70.4 months (interquartile range, 44.1-111.2 months), the left atrial ablation group presented a higher risk of atrial fibrillation recurrence (subdistribution hazard ratio, 1.26; 95% CI, 1.12-1.41; P < .001), with a 5-year cumulative incidence of 34.2% compared with 28.6% in the biatrial group. The risk of late mortality (subdistribution hazard ratio, 1.17; 95% CI, 0.74-1.86; P = .507) and stroke (subdistribution hazard ratio, 1.21; 95% CI, 0.82-1.79; P = .345) did not differ between the groups.

CONCLUSIONS

In patients undergoing surgical ablation concomitant to mitral valve surgery, both lesion sets provided comparable incidence of mortality and stroke. However, biatrial ablation was associated with a superior rhythm outcome at the expense of a higher risk of early pacemaker implantation.

The Society of Thoracic Surgeons 2023 Clinical Practice Guidelines for the Surgical Treatment of Atrial Fibrillation

The Society of Thoracic Surgeons 2023 Clinical Practice Guidelines for the Surgical Treatment of Atrial Fibrillation incorporate the most recent evidence for surgical ablation and left atrial appendage occlusion in different clinical scenarios. Substantial new evidence regarding the risks and benefits of surgical left atrial appendage occlusion and the long-term benefits of surgical ablation has been produced in the last 5 years. Compared with the 2017 clinical practice guideline, the current update has an emphasis on surgical ablation in first-time, nonemergent cardiac surgery and its long-term benefits, an extension of the recommendation to perform surgical ablation in all patients with atrial fibrillation undergoing first-time, nonemergent cardiac surgery, and a new class I recommendation for left atrial appendage occlusion in all patients with atrial fibrillation undergoing first-time, nonemergent cardiac surgery. Further guidance is provided for patients with structural heart disease and atrial fibrillation being considered for transcatheter valve repair or replacement, as well as patients in need of isolated left atrial appendage management who are not candidates for surgical ablation. The importance of a multidisciplinary team assessment, treatment planning, and long-term follow-up are reiterated in this clinical practice guideline with a class I recommendation, along with the other recommendations from the 2017 guidelines that remained unchanged in their class of recommendation and level of evidence.

Surgical ablation for atrial fibrillation during aortic and mitral valve surgery: A nationwide population-based cohort study

OBJECTIVE

There is limited evidence on the effectiveness of surgical atrial fibrillation ablation in reducing mortality or thromboembolic events during aortic/mitral valve surgery. We evaluated the association of surgical ablation versus no ablation with risks of all-cause death and ischemic stroke or systemic embolization among patients with preoperative atrial fibrillation undergoing concomitant aortic valve or mitral valve surgery.

METHODS

With the use of administrative healthcare datasets from the Korean National Health Insurance Service database between 2003 and 2018, adult patients with atrial fibrillation undergoing aortic/mitral valve replacement or mitral valve repair were enrolled, and their outcomes were compared according to the performance of concomitant surgical ablation. The primary end points were all-cause death and thromboembolic event of ischemic stroke or systemic embolization.

RESULTS

Among 17,247 patients with atrial fibrillation undergoing aortic/mitral valve surgery, 8716 (50.5%) received surgical ablation, whereas 8531 (49.5%) did not. During a median follow-up of 6.7 years (124,842.2 patient-years), death was less in the ablation group than in the no-ablation group (2.7 vs 4.1 patient-years; P < .001). The incidence of ischemic stroke or systemic embolization was also lower in the ablation group (0.9 vs 1.3 patient-years; P < .001). After adjustment with inverse probability of treatment weighting, surgical ablation was associated with decreased risks of all-cause death (hazard ratio, 0.86; 95% confidence interval, 0.80-0.92), ischemic stroke or systemic embolization (hazard ratio, 0.62; 95% confidence interval, 0.55-0.71), and hospitalization from heart failure (hazard ratio, 0.87; 95% confidence interval, 0.79-0.96).

CONCLUSIONS

In patients with atrial fibrillation undergoing aortic/mitral valve surgery, concomitant surgical ablation was significantly associated with lower risks of mortality and thromboembolic events.

Functional Insufficiency of Mitral and Tricuspid Valves Associated With Atrial Fibrillation: Impact of Postoperative Atrial Fibrillation Recurrence on Surgical Outcomes

BACKGROUND AND OBJECTIVES

To identify the factors associated with adverse outcomes following surgery for functional insufficiency of the mitral valve (MV) or tricuspid valve (TV) associated with atrial fibrillation (AF).

METHODS

We evaluated 100 patients (age, 66.5±10.0 years; 47 males) who consecutively underwent surgery for functional insufficiency of the MV or TV associated with AF between January 2000 and December 2020 at our center. The primary outcome was a composite endpoint of all-cause death, valve reoperation, congestive heart failure (CHF) requiring rehospitalization, and stroke.

RESULTS

During follow-up (532 patients-years [PYs]), adverse events included death in 16 (3.0%/yr), MV reoperation in 1 (0.2%/yr), CHF in 14 (2.6%/yr), and stroke in 5 (0.9%/yr) patients, demonstrating a 5-year rate of freedom from the primary endpoint of 69.5%. The rate of postoperative AF was high even in those who underwent AF ablation (n=92), with cumulative rates of 48.1% at 1 year and 60.2% at 5 years. In multivariable analyses, the primary outcome was significantly associated with age (adjusted hazard ratio [aHR], 1.06; 95% confidence interval [CI], 1.02-1.10; p=0.005), chronic kidney disease (aHR, 7.76; 95% CI, 2.28-26.38; p=0.001), left atrial appendage exclusion (aHR, 0.35; 95% CI, 0.16-1.78; p=0.010), and postoperative AF as a time-varying covariate (aHR, 3.33; 95% CI, 1.50-7.40; p=0.003).

CONCLUSION

Among patients undergoing surgery for functional atrioventricular insufficiency associated with AF, a significant proportion showed recurrence of AF over time after concomitant AF ablation, which was significantly associated with poor clinical outcomes.

Decision-Making in Transcatheter Edge-to-Edge Repair: Insights into Atrial Functional Mitral Regurgitation

The 2020 American College of Cardiology focused update on the mitral regurgitation (MR) pathway provides an excellent summary of the decision-making trees in the treatment of severe MR, in which 2 main branches of the flowchart are suggested depending on whether MR is primary or secondary. Surgery is suggested as preferable over transcatheter edge-to-edge repair (TEER) in primary MR that needs intervention. The decision-making for secondary MR generally prioritizes TEER over surgery according to the guidelines, but further stratification is necessary based on the pathophysiologic mechanisms of MR. TEER is probably the more suitable option in secondary MR caused by left ventricular dysfunction or dilatation, given the high perceived surgical risks, despite the lack of sufficient evidence in support of overt clinical benefits from surgical therapy in these patients. In atrial functional MR associated with atrial fibrillation (AF), however, concomitant ablation of AF seems to be a desirable option, as it has been demonstrated to be a key factor leading to improved survival, reduced stroke risk, and more durable mitral and tricuspid function in patients undergoing mitral surgery. Therefore, atrial functional MR requiring intervention may be best treated by surgical therapy that combines mitral repair and AF ablation in the majority of patients. This particular issue, however, needs further research to obtain scientific evidence to guide optimal management strategies.