Concomitant ablation of atrial fibrillation in rheumatic mitral valve surgery

Chinese guidelines for the diagnosis and management of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of the guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice timely and fully, the Chinese Society of Cardiology of Chinese Medical Association and the Heart Rhythm Committee of Chinese Society of Biomedical Engineering jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2‑VASc‑60 stroke risk score based on the characteristics of the Asian AF population. The guidelines also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice in a timely and comprehensive manner, the Chinese Society of Cardiology of the Chinese Medical Association and the Heart Rhythm Committee of the Chinese Society of Biomedical Engineering have jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines have comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2-VASc-60 stroke risk score based on the characteristics of AF in the Asian population. The guidelines have also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

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.

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.

Superiority of complete bi-atrial ablation procedure for atrial fibrillation in rheumatic mitral valve disease

INTRODUCTION

The necessity of complete bi-atrial lesion created by radiofrequency clamp and pen for nonparoxysmal atrial fibrillation (AF) in patients with rheumatic mitral valve disease (RMVD) remains unclear.

METHODS

From January 2014 to December 2018, patients with RMVD concomitant with nonparoxysmal AF who underwent mitral valve surgery concomitant surgical ablation were retrospectively enrolled. We divided patients into Group A (complete bi-atrial lesion set created by radiofrequency clamp and pen) and Group B (simplified lesion sets created by radiofrequency clamp alone including bi-atrial ablation with incomplete mitral isthmus line and stand-alone left atrial ablation) according to the surgical ablation lesion sets. Propensity score matching was applied to analyze freedom from atrial tachyarrhythmias between the two groups.

RESULTS

Two hundred eight (38.5%) and 332 (61.5%) patients were divided into Group A and Group B, respectively. In Group B, the proportion of patients with recurrent atrial flutter in the subgroup of bi-atrial ablation with incomplete mitral isthmus line was higher than that in Group A (p = .044). After propensity score matching, there were 203 patients in each group. Better freedom from atrial tachyarrhythmias without antiarrhythmic drugs was obtained in Group A (83.1%, 79.6%, and 65.4%) than Group B (73.1%, 68.4%, and 52.7%) at 12, 36, and 60 months after operation (p = .012).

CONCLUSION

The application of radiofrequency clamp and pen to create complete bi-atrial lesion set in surgical ablation for nonparoxysmal AF in RMVD was associated with superior long-term efficacy.

Combined atrial fibrillation ablation and balloon mitral commissurotomy in patients with rheumatic mitral stenosis

INTRODUCTION

Ablation of atrial fibrillation (AF) is usually not considered in patients with rheumatic mitral stenosis (RMS). We analyzed the results of a combined procedure of AF ablation and percutaneous balloon mitral commissurotomy (PBMC).

METHODS

We prospectively included 22 patients with severe RMS to undergo a combined PBMC + AF ablation procedure. Noninvasive mapping of the atria was also performed. A historical sample of propensity-scored matched patients who underwent PBMC alone was used as controls. The primary endpoint was freedom from AF/AT at 1-year. Multivariate analysis evaluated sinus rhythm (SR) predictors.

RESULTS

Successful pulmonary vein isolation and electrocardiographic imaging-based drivers ablation was performed in 20 patients following PBMC. At 1-year, 75% of the patients in the combined group were in SR compared to 40% in the propensity-score matched group (p = 0.004). The composite of AF recurrence, need for mitral surgery and all-cause mortality was also more frequent in the control group (65% vs. 30%; p = 0.005). Catheter ablation (odds ratio [OR] 1.58; 95% confidence interval [CI] [1.17-17.37]; p = 0.04) and AF type (OR 1.46; 95% CI [1.05-82.64]; p < 0.001) were the only independent predictors of SR at 1-year. Noninvasive mapping in the combined group showed that the number of simultaneous rotors (OR 2.10; 95% CI [1.41-10.2]; p = 0.04) was the only independent predictor of AF.

CONCLUSION

A combined procedure of AF ablation and PBMC significantly increased the proportion of patients in sinus rhythm at 1-year. Noninvasive mapping may help to improve AF characterization and guide personalized AF treatment.

Bi-atrial versus left atrial ablation for patients with rheumatic mitral valve disease and non-paroxysmal atrial fibrillation (ABLATION): rationale, design and study protocol for a multicentre randomised controlled trial

INTRODUCTION

Atrial fibrillation (AF) is common in patients with rheumatic mitral valve disease (RMVD) and increase the risk of stroke and death. Bi-atrial or left atrial ablation remains controversial for treatment of AF during mitral valve surgery. The study aims to compare the efficacy and safety of bi-atrial ablation with those of left atrial ablation among patients with RMVD and persistent or long-standing persistent AF.

METHODS AND ANALYSIS

The ABLATION trial (Bi-atrial vs Left Atrial Ablation for Patients with RMVD and Non-paroxysmal AF) is a prospective, multicentre, randomised controlled study. The trial will randomly assign 320 patients with RMVD and persistent or long-standing persistent AF to bi-atrial ablation procedure or left atrial ablation procedure in a 1:1 randomisation. The primary end point is freedom from documented AF, atrial flutter or atrial tachycardia of >30 s at 12 months after surgery off antiarrhythmic drugs. Key secondary end point is the probability of freedom from permanent pacemaker implantation at 12 months after surgery. Secondary outcomes include the probability of freedom from any recurrence of atrial tachyarrhythmias with antiarrhythmic drugs, AF burden, incidence of adverse events and cardiac function documented by echocardiography at 12 months after operation.

ETHICS AND DISSEMINATION

The central ethics committee at Fuwai Hospital approved the ABLATION trial. The results of this study will be disseminated through publications in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05021601.

Effect of electrophysiological mapping on non-transmural annulus ablation and atrial fibrillation recurrence prediction after 6 months of Cox-Maze IV procedure

Objective

The objective of this study was to observe the safety and efficacy of electrophysiological mapping following the Cox-Maze IV procedure and to investigate whether a correlation exists between recurrence of atrial fibrillation (AF) with the completeness of bidirectional electrical isolation and the inducibility of AF immediately after the Cox-Maze IV procedure.

Methods

Totally, 80 consecutive patients who suffered from aortic valve or mitral valve disease and persistent AF were randomly enrolled into the control group and electrophysiological mapping following the Cox-Maze IV group (Electrophysio-Maze group). In the Electrophysio-Maze group, patients underwent concomitant Cox-Maze procedure and following electrophysiological mapping of ablation lines in mitral isthmus, left atrial “box,” and tricuspid annulus. If the bidirectional electrical isolation of tricuspid annulus ablation line is incomplete, whether to implement supplementary ablation will be independently decided by the operator. Before and after the Cox-Maze IV procedure, AF induction was performed. All patients in both groups were continuously followed-up and underwent electrocardiogram Holter monitoring after 6 months.

Results

In total, 42 Electrophysio-Maze patients and 38 controls were enrolled. Compared with patients in the control group, there were shorter hospital stay, better cardiac remodeling changes, and higher relief from AF during the follow-up period of 6 months in the Electrophysio-Maze group. Within the Electrophysio-Maze group, the rate of incomplete the bidirectional electrical isolation of “box” ablation lines was zero, and the rate of incomplete bidirectional electrical isolation of mitral isthmus ablation line or tricuspid annulus ablation line was 23.8%. After two cases of successful complementary ablation on the tricuspid annulus ablation line, the final incomplete bidirectional electrical isolation of annulus ablation lines was 19.0%. There were correlations between late AF recurrence after 6 months with incomplete bidirectional electrical isolation of annulus ablation lines and AF induction immediately after the Cox-Maze IV procedure.

Conclusion

Electrophysiological mapping following the Cox-Maze procedure is safe and effective. Electrophysiological mapping in the Cox-Maze procedure can find out the non-transmural annulus ablation lines by assessing the completeness of bidirectional electrical isolation of ablation lines, guide supplementary ablation, and predict AF recurrence after 6 months.

Efficiency and safety of ablation procedure for the treatment of atrial fibrillation in valve surgery: A PRISMA-compliant cumulative systematic review and meta-analysis

BACKGROUND

Atrial fibrillation is the main complication of patients who suffer from valvular heart disease (VHD), which may lead to an increased susceptibility to ventricular tachycardia, atrial dysfunction, heart failure, and stroke. Therefore, seeking a safe and effective therapy is crucial in prolonging the lives of patients with VHD and improving their quality of life.

METHODS

Our target database included PubMed, Web of Science, Embase, and Cochrane Library, from which published articles were retrieved from inception to June 2020. We retrieved all randomized controlled trials (RCTs) that compared patients undergoing valve surgery with (VSA) or without ablation (VS) procedure. Studies to be included were screened and data extraction was performed independently by 2 investigators. The Cochrane risk-of-bias table was used to evaluate the methodological quality of the included RCTs. The mean difference (MD) with 95% confidence interval (CI) and relative risk (RR) ratio was calculated to analyze the data. Heterogeneity was evaluated using I2 and chi-square tests. Egger test and the trim and fill analysis were used to further determine publication bias.

RESULTS

Fourteen RCTs that included 1376 patients were eventually selected for this meta-analysis. Surgical ablation was found to be effective in restoring sinus rhythm in valvular surgery patients at discharge (RR 2.91, 95% CI [1.17, 7.20], I2 97%, P = .02), 3 to 6 months (RR 2.85, 95% CI [2.27, 3.58], I2 49%, P < .00001), 12 months, and more than 1 year after surgery (RR 3.54, 95% CI [2.78, 4.51], I2 27%, P < .00001). All-cause mortality (RR 0.98, 95% CI [0.64, 1.51], I2 0%, P = .94) and stroke (RR 1.29, 95% CI [0.70, 2.39], I2 0%, P = .57) were similar in the VSA and VS groups. Compared with VS, VSA prolonged cardiopulmonary bypass time (MD 30.44, 95% CI [17.55, 43.33], I2 88%, P < .00001) and aortic cross-clamping time (MD 19.57, 95% CI [11.10, 28.03], I2 89%, P < .00001). No significant differences were found between groups with respect to the risk of bleeding (RR 0.64, 95% CI [0.37, 1.12], I2 0%, P = .12), heart failure (RR 1.11, 95% CI [0.63, 1.93], I2 0%, P = .72), and low cardiac output syndrome (RR 1.41, 95% CI [0.57, 3.46], I2 18%, P = .46). However, the demand for implantation of a permanent pacemaker was significantly higher in the VSA group (RR 1.84, 95% CI [1.15, 2.95], I2 0%, P = .01).

CONCLUSION

Although we found high heterogeneity in the restoration of sinus rhythm at discharge, we assume that the comparison is valid at this time, given the current state in the operating room. This study provides evidence of the efficacy and security of concomitant ablation intervention for patients with VHD and atrial fibrillation. Surgical ablation would increase the safety of implantation of a permanent pacemaker in the population that underwent valve surgery.

Surgical ablation in rheumatic heart disease-Uncharted territory

BACKGROUND

Atrial fibrillation is a common arrhythmia with a large impact on society and on patients. Rheumatic valve disease is still prevalent in low- and medium-income countries. Performing surgical ablation during surgery for mitral valve disease has been shown to restore sinus rhythm in most patients.

AIMS, MATERIALS AND METHODS

In this issue of the Journal of Cardiac Surgery, Ma et al., publish a meta-analysis of surgical ablation in patients with rheumatic heart disease (RHD).

RESULTS

They found no difference in short-term outcomes with a higher incidence of restoration to sinus rhythm. In mid- to long-term follow-up, there was no difference in mortality with a signal towards more permanent pacemaker implantation.

DISCUSSION AND CONCLUSION

Despite some inherent limitations and some methodological flows, this meta-analysis has important insights and is valuable for surgeons taking care of patients with RHD.

Safety and efficacy of concomitant ablation for atrial fibrillation in rheumatic mitral valve surgery: A meta-analysis

OBJECTIVES

This review aimed to evaluate the safety and efficacy of concomitant surgical ablation (SA) for patients with atrial fibrillation (AF) undergoing rheumatic mitral valve (MV) surgery.

METHODS

A systematic search of relevant studies focusing on SA for patients with AF undergoing rheumatic MV surgery was performed. The primary outcomes included mortality, efficacy, and complications.

RESULTS

Four randomized controlled trials (RCTs) and four observational studies covering 1931 patients met the inclusion criteria. In RCTs, no significant differences in reoperation for bleeding, low cardiac output syndrome, thromboembolic events, and early (risk ratio [RR], 2.07; 95% confidence intervals [CI], 0.37-11.40; p = .41) and midterm all-cause death (RR, 1.07; 95% CI, 0.40-2.88; p = .89) were noted between the SA group and the nonablation group. These results were similar to those obtained from observational studies. However, ablation was associated with a higher incidence of permanent pacemaker implantation (RR, 2.44; 95% CI, 1.15-5.18; p = .02) in observational studies but not in RCTs (RR, 2.03; 95% CI, 0.19-21.26; p = .56). Furthermore, additional SA was significantly more effective in sinus rhythm (SR) restoration than MV surgery alone at discharge and at the 12-month and 3-year follow-ups.

CONCLUSIONS

Concomitant SA during rheumatic MV surgery does not increase perioperative adverse events. In addition, SA promotes considerable restoration of SR. Although some evidence exists that permanent pacemaker implantation is more common after ablation, not all studies support this notion.

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.

Long-Term Outcomes of Surgical Ablation for Atrial Fibrillation: Impact of Ablation Lesion Sets

BACKGROUND

The lesion sets for surgical ablation of atrial fibrillation (AF) that provide optimal outcomes have remained controversial.

OBJECTIVES

We evaluated the effects of left-atrial (LA) ablation of AF compared with bi-atrial (BA) ablation on the clinical and rhythm outcomes, and examined the predictors for AF recurrence and permanent pacing in consideration of ablation lesion sets.

METHODS

Between 2001 and 2018, 1,965 patients underwent surgical ablation during cardiac surgery at our institution. Among these, 796 and 1,169 patients underwent LA and BA ablation, respectively. The clinical outcomes were evaluated after propensity score adjustment, with death accounting for a competing event. The probability of AF recurrence was estimated with the generalized estimating equations model.

RESULTS

The patients with BA ablation had morbidities greater than those with LA ablation. The probability of AF recurrence at 1 and 5 years was 13.9% and 37.1% in patients with LA ablation, and 11.2% and 30.1% in those with BA ablation (hazard ratio [HR]: 1.24; 95% confidence interval [CI]: 0.96-1.61; P = 0.100). After adjustment, LA ablation was associated with a decreased risk of early death (<30 days) (odds ratio [OR]: 0.56; 95% CI: 0.31-0.96; P = 0.041) and new-onset dialysis (OR 0.47; 95% CI: 0.27-0.78; P = 0.003). However, the risk of overall mortality (HR: 1.03; 95% CI: 0.75-1.41; P = 0.878) and permanent pacing (HR: 0.68; 95% CI: 0.43-1.06; P = 0.091) was comparable between the 2 groups.

CONCLUSIONS

The risk of AF recurrence and adverse events was comparable between the 2 ablation lesion sets. BA ablation was not related to an increased risk of permanent pacing.

The Characteristics, Long-Term Outcomes, Risk Factors, and Antithrombotic Therapy in Chinese Patients With Atrial Fibrillation and Bioprosthetic Valves

Introduction: There were few data about the clinical profiles and long-term outcomes in Chinese patients with atrial fibrillation (AF) and bioprosthetic valves.

Methods: The retrospective study enrolled 903 patients with bioprosthetic valve replacement at our hospital and discharged with a diagnosis of AF from January 2010 to December 2018.

Results: The median age was 65.6 (61.9–69.1) years, and 548 (60.7%) patients were women. During a follow-up period of 3.84 (2.64–5.51) years, 68 (1.8 per 100 person-years) patients died, 81 (2.1 per 100 person-years) patients developed thromboembolism, and 23 (0.6 per 100 person-years) patients experienced major bleeding. The CHA₂DS₂-VASc score, as a categorical variable (low, moderate, or high risk), predicted the risk of thromboembolism with the C-statistic of 0.6 (95% CI: 0.511–0.689, p = 0.046). The incidence of the CHA₂DS₂-VASc score increment was 11.6 per 100 person-years, and the annual reclassification rate of stroke risk (from a low or moderate group to a higher group) was 12.7%. The current proportion of oral anticoagulants was 52.3, 59, and 63.2%, respectively, in the low, moderate, and high stroke risk groups. Age (OR: 1.04, 95% CI: 1.01–1.06, p = 0.01), left atrial size (OR: 1.05, 95% CI: 1.03–1.08, p < 0.001), and rheumatic heart disease (OR: 1.49, 95% CI: 1.05–2.10, p = 0.025) were positively associated with the use of oral anticoagulants. The history of chronic kidney disease (OR: 0.20, 95% CI: 0.05–0.76, p = 0.018), prior surgical ablation (OR: 0.33, 95% CI: 0.24–0.47, p < 0.001), and antiplatelet agent use (OR: 0.08, 95% CI: 0.05–0.13, p < 0.001) were inversely related to the use of oral anticoagulants. Higher admission estimated glomerular filtration rate (HR: 0.515, 95% CI: 0.311–0.853, p = 0.01), left ventricular ejection fraction (HR: 0.961, 95% CI: 0.931–0.992, p = 0.014), concomitant surgical ablation (HR: 0.348, 95% CI: 0.171–0.711, p = 0.004), and rheumatic heart disease history (HR: 0.515, 95% CI: 0.311–0.853, p = 0.01) were associated with a lower risk of death. Surgical ablation (HR: 0.263, 95% CI: 0.133–0.519, p < 0.001) and oral anticoagulants (HR: 0.587, 95% CI: 0.375–0.918, p = 0.019) were related to a lower risk of thromboembolism.

Conclusion: Chinese patients with AF and bioprosthetic valve(s) were relatively young and had a high prevalence of rheumatic heart disease with few comorbidities. The percentage of mitral bioprosthetic valve replacement was high. The proportion of concomitant surgical ablation or surgical left atrial appendage occlusion or exclusion was relatively low. The thromboembolic events were the major long-term adverse events. The anticoagulation therapy was underused in patients at moderate or high stroke risk. The CHA₂DS₂-VASc score was verified to be used for predicting stroke risk in this population. The stroke risk dynamically changed; it needed to be reestimated once the risk factor changed.

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

The benefit of avoiding lifelong anticoagulation therapy in patients with bioprosthetic heart valve implantation may potentially be offset by atrial fibrillation (AF); however, clinical impact of surgical AF ablation in such patients remains controversial. We enrolled 426 patients (aged 72.0 ± 7.8 years) with AF who underwent left-side valve replacement with bioprostheses between 2001 and 2018. Of these, 297 underwent concomitant surgical ablation (ablation group) and 129 underwent valve replacement alone (non-ablation group). Clinical outcomes were compared, and mortality was considered as a competing risk factor against valve-related complications. Inverse-probability weighting (IPTW) was adopted to reduce selection bias. The ablation group had lower baseline risk profiles than the non-ablation group. In crude analysis, early mortality rates were 3.4% and 7.0% in the ablation and non-ablation groups, respectively (P = 0.104). During follow-up (1521.9 patient-years), the ablation group showed lower AF-recurrence (P < 0.001) and anticoagulant medication rate (P = 0.021), and lower overall mortality risk (subdistribution hazard ratio [SHR], 0.63; 95% confidence interval [CI], 0.42-0.94), but higher risk of permanent pacemaker implantation (SHR, 4.67; 95% CI, 1.36-16.05). No significant difference in the risk of stroke (SHR, 1.27; 95% CI, 0.55-2.95) was observed between the groups. After baseline IPTW-adjustment, findings of the clinical outcomes were analogous to those from crude analyses. In patients undergoing bioprosthetic valve replacement, the addition of surgical ablation was associated with improved rhythm outcomes and survival but at the expense of a higher risk of pacemaker implantation. The underlying mechanism of improved survival by AF ablation needs further investigation.

Isolated left atrial cryoablation of atrial fibrillation in conventional mitral valve surgery

Background

Recent trends of surgery for atrial fibrillation (AF) are towards more safe and effective energy sources, as well as to simplified sets of atrial lesions.

Methods

One hundred eighteen (mean age, 67.4 ± 9.2 years) selected patients with paroxysmal/persistent AF and mitral valve (MV) disease underwent cryoablation of AF combined with conventional (not via mini-thoracotomy) MV surgery; the lesion set was limited to only the left atrium. Multivariable analyses identified predictors of cardiac rhythm at hospital discharge and follow-up.

Results

There were 7 (5.9%) hospital deaths; 33 (28%) patients were discharged on AF. Higher values of preoperative left atrial volume index (odds ratio [OR] = 1.07, 95% confidence interval [95%CI]: 1.01-1.13) and mixed etiology of MV disease (OR = 4.19, 95%CI: 1.23-14.2) were predictors of hospital discharge on AF. Seventy-four (66.7%) patients were on stable sinus rhythm at follow-up (median period, 6.6 years); the 1, 5, and 10-year nonparametric estimates of adjusted freedom from AF were 98.1%, 89.2% and 45.6%, respectively. Higher values of preoperative systolic pulmonary artery pressure (hazard ratio [HR] = HR = 1.04, 95%CI: 1.01-1.08) and AF at hospital discharge (HR = 4.14, 95%CI: 1.50-11.4) were predictors of AF at follow-up.

Conclusions

During conventional MV surgery, a cryo-lesion set limited to only the left atrium may give good, immediate and long-term results. Left atrial dilation and mixed etiology of MV disease were predictors of hospital discharge on AF. Preoperative pulmonary hypertension and AF at discharge combined with an increased risk of AF at follow-up.

Exclusion versus preservation of the left atrial appendage in rheumatic mitral valve surgery

OBJECTIVES

This study aimed to evaluate the impact of left atrial appendage exclusion on clinical outcomes in patients with atrial fibrillation (AF) undergoing rheumatic mitral surgery.

METHODS

We retrospectively reviewed 1226 consecutive patients with AF (54.5±11.6 years; 68.2% females) who underwent rheumatic mitral valve (MV) surgery from 1997 to 2016. The left atrial appendage was preserved in 836 (68.2%) and excluded in 390 (31.8%) patients. Surgical AF ablation was performed in 506 (60.5%) and 304 (77.9%) patients with preserved and excluded left atrial appendage, respectively. For baseline adjustment, propensity matching was used.

RESULTS

During a median follow-up of 63.4 months (IQRs, 20-111 months), there were no significant intergroup differences in the risks of mortality (2.77% vs 3.03%/patient-years) and thromboembolic events (0.91% vs 1.02%/patient-years). In the 258 pairs of propensity-score matched patients, death (2.77% vs 3.03%/patient-years) and thromboembolism (1.36% vs 0.82%/patient-years) outcomes were comparable for both groups. In a subgroup undergoing ablation (n=810), there were no significant differences in the adjusted risks of death (HR, 0.67; 95% CI, 0.34 to 1.32) and thromboembolism (HR, 0.47; 95% CI, 0.18 to 1.26). In a subgroup not undergoing ablation (n=416), however, left atrial appendage preservation tended to have higher adjusted risks for death (HR, 2.24; 95% CI, 0.98 to 5.13) and thromboembolism (HR, 4.41; 95% CI, 0.97 to 20.1).

CONCLUSIONS

Left atrial appendage preservation did not seem to have greater risks of adverse clinical events in patients with AF undergoing rheumatic MV surgery particularly when ablation procedure is combined.

Atrial Fibrillation Ablation: Indications and Techniques

PURPOSE OF REVIEW

Atrial fibrillation (AF) predisposes to embolic strokes and reduced quality of life. Ablation (catheter-based or surgically performed) can be employed to promote the maintenance of sinus rhythm in a carefully selected subset of patients with AF. The goal of this review is to discuss the indications and techniques for AF ablation, as well as post-procedural outcomes.

RECENT FINDINGS

Atrial fibrillation ablation improves quality of life in patients with atrial fibrillation although no clear reduction in stroke or overall mortality has been shown. Familiarity with the indications for AF ablation is important for all cardiologists, as is having a sound understanding of the efficacy of the procedure and potential complications. Furthermore, acquiring a grasp of the different modalities of AF ablation (including percutaneous endocardial techniques and surgical ablation approaches) will help to facilitate effective and appropriate referrals.