Surgical ablation in patients undergoing mitral valve surgery: impact of lesion set and surgical techniques on long-term success

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.

Surgical Atrial Fibrillation Ablation With and Without Left Atrium Reduction for Patients Scheduled for Mitral Valve Surgery: A Prospective Randomised Study

BACKGROUND

The influence of left atrium (LA) enlargement on atrial arrhythmia recurrence (AAR) after surgical ablation in patients with mitral valve (MV) disease remains unresolved.

OBJECTIVE

Left atrial size is critical to the success of concomitant atrial fibrillation (AF) ablation in patients scheduled for MV surgery. However, a large LA should not be a limiting factor when evaluating surgical candidates with AF if they receive appropriate treatment during concomitant ablation. This randomised study assessed whether adding LA reduction (LAR) to the maze procedure for MV surgery patients can improve freedom from AAR.

METHODS

From September 2014 to September 2017, 140 patients were randomly assigned into two groups. The maze group underwent MV surgery with concomitant surgical AF ablation (n=70). The maze + LA reduction group underwent MV surgery with concomitant AF ablation and LA reduction procedure (n=70). Rhythm outcomes were estimated by Holter monitoring, according to Heart Rhythm Society guidelines.

RESULTS

The concomitant LA reduction procedure did not increase early mortality and complications rates. Significant differences in freedom from AAR were observed at 24 months (maze, 78.4%; maze + LAR group, 92.3%; p=0.025). A significant difference in LA volume was detected at discharge (p<0.0001); however, it was not significantly different at 24 months (p=0.182).

CONCLUSIONS

Adding LA reduction to the maze procedure led to improvements in freedom from AAR for patients with AF and LA enlargement scheduled for MV surgery. A concomitant LA reduction procedure did not increase mortality and perioperative risk.

Catheter ablation or surgical therapy in moderate-severe tricuspid regurgitation caused by long-standing persistent atrial fibrillation. Propensity score analysis

BACKGROUND

This study aimed to describe the mid-term outcomes of different treatments in patients with atrial fibrillation caused tricuspid regurgitation.

METHODS

A retrospective study of patients diagnosed as atrial fibrillation caused moderate-severe tricuspid regurgitation undergoing ablation (n = 411) were reviewed. The surgical cohort (n = 114) underwent surgical ablation and tricuspid valve repair; the catheter cohort (n = 279) was selected from those patients who had catheter ablation.

RESULTS

The estimated actuarial 5-year survival rates were 96.8% (95% CI: 92.95-97.78) and 92.0% (95% CI: 85.26-95.78) in the catheter and surgical cohort, respectively. Tethering height was showed as independent risk factors for recurrent atrial fibrillation and tricuspid regurgitation in both cohorts. A matched group analysis using propensity-matched was conducted after categorizing total patients by tethering height < 6 mm and ≥ 6 mm. Kaplan-Meier analysis showed in patients with tethering height < 6 mm, there were no differences in survival from mortality, stroke, recurrent atrial fibrillation and tricuspid regurgitation between two groups. In patients with tethering height ≥ 6 mm, there were significantly higher cumulative incidence of stroke (95% CI, 0.047-0.849; P = 0.029), recurrent atrial fibrillation (95% CI, 0.357-09738; P = 0.039) and tricuspid regurgitation (95% CI, 0.359-0.981; P = 0.042) in catheter group.

CONCLUSIONS

Atrial fibrillation caused tricuspid regurgitation resulted in less leaflets coaptation, which risk the recurrence of atrial fibrillation and tricuspid regurgitation. Patients whose tethering height was less than 6 mm showed satisfying improvement in tricuspid regurgitation with the restoration of sinus rhythm after catheter ablation. However, in patients with severe leaflets tethering, the results favored surgical over catheter.

Safety and efficacy of biatrial vs left atrial surgical ablation during concomitant cardiac surgery: A meta-analysis of clinical studies with a focus on the causes of pacemaker implantation

INTRODUCTION

The latest STS guidelines recommend concomitant atrial fibrillation (AF) ablation not only during mitral surgery (Class IA) but also during other-than-mitral cardiac surgery procedures (Class IB) in patients with preoperative AF. Conventional Cox-Maze III/IV procedures are performed on both atria (BA), but several studies reported excellent results with left atrial only (LA) ablations: the scope of this study is to compare the safety and efficacy of BA vs LA approach.

METHODS AND RESULTS

Pubmed, Scopus, and WOS were searched from inception to November 2018: 28 studies including 7065 patients and comparing the performance of BA vs LA approaches were identified: of these, 16 (57.1%) enrolled exclusively patients with non-paroxysmal AF forms, 10 (35.7%) focused on mitral surgery as main procedure, and 16 (57.1%) regarded patients undergone Cox-Maze with radiofrequency. The 6- and 12-months prevalence of sinus rhythm were higher in the BA group (OR, 1.37, CI, 1.09-1.73, P = .008 and OR, 1.37, CI, 0.99-1.88, P = .05 respectively). Permanent pacemaker (PPM) implantation (OR, 1.85, CI, 1.38-2.49, P < .0001) and reopening for bleeding (OR, 1.70, CI, 1.05-2.75, P = .03) were higher in the BA group. Among patients undergone PPM implantation, BA group had a significantly higher risk of sinoatrial node dysfunction (OR, 3.01, CI, 1.49-6.07, P = .002).

CONCLUSIONS

Concomitant BA ablation appears superior to LA ablation in terms of efficacy but is associated with a higher risk of bleeding and of PPM implantation, more frequently due to sinoatrial node dysfunction. LA approach should be preferable in patients with a higher risk of bleeding or with perioperative risk factors for PPM implantation.

The long-term efficacy of concomitant maze IV surgery in patients with atrial fibrillation

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and associated with increased risk of morbidity and mortality. AF surgery is widely used for rhythm control of AF, but previous studies have shown varying results. This study sought to investigate the long-term efficacy of concomitant maze IV (CMIV) surgery in an unselected AF population and identify predictors of late AF recurrence.

Methods

In total 144 consecutive patients, who underwent CMIV between January 2006 and December 2010 were enrolled. By data from electronic medical records, registers, and rhythm prints, late AF recurrences and heart rhythm at latest follow-up were retrospectively registered. All patients still alive were invited to an ambulant follow-up to update rhythm status.

Results

During a median (IQR) follow-up of 7.39 (2.67) years, 114 (79.2%) patients had recurrence. The cumulative incidence of sinus rhythm (SR) without antiarrhythmic drugs (AADs) was 52.3% after 1 year. Long-term results after 2, 5 and 7 years were 47.9%, 32.6% and 25.1%, respectively. At latest follow-up 34.7% were in SR off AADs. No difference in 10-year event-free survival stratified by recurrence were found (p = 0.678). Contrary, time to death (5.40 vs. 3.43 years, p = 0.004) revealed death as competing risk event. The Fine-Gray model identified preoperative sustained AF (SAF) (SHR 3.54, 95%CI [2.35;5.32], p < 0.001), AF duration (1.08, [1.05;1.11], p < 0.001), and postoperative atrial tachyarrhythmia (ATA) (2.29, [1.21;4.35], p = 0.011) as predictors.

Conclusion

CMIV in the present cohort provided limited long-term success in obtaining SR. SAF, longer AF duration, and postoperative ATA were associated with late AF recurrence.

Rhythmic and haemodynamic determinants of long-term survival after radiofrequency ablation of atrial fibrillation in mitral valve surgery

Aims

The aim of the present study was to evaluate the effects of sinus rhythm recovery on long-term survival after radiofrequency (RF) ablation in patients with permanent atrial fibrillation (AF) undergoing surgery for mitral valve disease.

Methods and results

This study included 173 consecutive patients (101 men and 72 women, age 67 ± 9 years) with AF and mitral valve disease who underwent RF ablation procedure associated with mitral valve surgery. Four patients died during hospitalization. At the 6-year follow-up, sinus rhythm was present in 68% of the surviving patients. Thirty-nine patients remained in persistent AF after hospital discharge. In patients with stable sinus rhythm, mortality (10 vs. 30%) and recurrent hospitalization were significantly lower than in patients with persistent AF, but functional capacity improved. The incidence of stroke was also lower in patients with stable sinus rhythm. A pre-operative higher right and left atrial area, pulmonary hypertension, and rheumatic disease were associated with the persistence of AF despite RF ablation. At multivariate analysis, only age and concomitant tricuspid valve repair were independently associated with mortality, whereas the right atria area and tricuspid valve repair were associated with persistent AF.

Conclusion

Although the re-establishment of sinus rhythm by unipolar RF ablation is associated with a higher survival rate after mitral valve surgery, our data suggest that a more severe haemodynamic impairment, in particular in patients with rheumatic valve disease, may be responsible both for higher long-term mortality and lower rate of sinus rate maintenance.

Sinus Rhythm Restoration after Radiofrequency Ablation Improves Survival in Patients Undergoing Mitral Valve Surgery : A Eight Year Single Center Study

Background

The usefulness of radiofrequency (RF) ablation in restoring sinus rhythm in patients with permanent atrial fibrillation (AF) undergoing surgery for mitral valve has been demonstrated. But whether sinus rhythm recovery affects long-term survival is less clear.

Methods

This study included 301 consecutive patients (126 men and 175 women, age 69±6 years) undergoing radiofrequency ablation of persistent atrial fibrillation along with mitral valve surgery. Radiofrequency ablation was performed using unipolar probe in 55.3%, bipolar probe in the remaining 44.7% of cases.

Results

Four patients died during hospitalization. At follow-up, sinus rhythm was present in 76% of the surviving patients. 71 patients never recovered sinus rhythm after hospital discharge. Mortality and recurrent hospitalization were significantly lower in patients with sinus rhythm at the end of follow-up in comparison to permanent AF. The incidence of stroke was also lower in patients with stable sinus rhythm. Larger atria, pulmonary hypertension and history of rheumatic disease were associated with the persistence of AF despite radiofrequency ablation. Although survival and functional capacity were significantly lower in patients with permanent AF at multivariate analysis only age and pulmonary artery pressure before surgery were independently associated with mortality.

Conclusion

Sinus rhythm restoration by RF ablation in patients undergoing mitral valve surgery is associated with an improved long-term survival. However our results suggest that a more severe hemodynamic impairment, expressed by higher pulmonary artery pressure, and increasing age are the only independent factors related to long-term survival.

Impact of Surgical Ablation of Atrial Fibrillation on the Progression of Tricuspid Regurgitation and Right-Sided Heart Remodeling After Mitral-Valve Surgery: A Propensity-Score Matching Analysis

BACKGROUND

This study assessed the role of surgical ablation for atrial fibrillation (AF) in decreasing tricuspid regurgitation (TR) and right-sided heart remodeling in patients after mitral valve procedure.

METHODS AND RESULTS

Between 1994 and 2014, 1568 consecutive patients with AF undergoing mitral valve procedure were identified. In 26.0% (n=408), surgical ablation of AF was used. Propensity-score matching (PSM) was performed on the basis of 41 known perioperative risk variables. Survival, reoperation, stroke, and moderate-to-severe TR, as well as echocardiography indices in long-term follow-up, were compared in 406 matched patient pairs (ablated and nonablated groups). The nonablated group showed significantly higher risks of death (hazard ratio [HR], 1.644; 95% CI, 1.081-2.501; P=0.020), reoperation (HR, 2.644; 95% CI, 1.299-5.466; P=0.008), and moderate-to-severe TR (HR, 1.436; 95% CI, 1.059-1.948; P=0.020), associated with a significantly deteriorated cardiac function, progression of TR, and right-sided heart remodeling after 5-year follow-up. In a subgroup comparison of ablated patients with sinus rhythm versus AF recurrence, a PSM analysis was performed at the 5-year follow-up. The recurrent group showed significantly higher risks of moderate-to-severe TR (HR, 2.427; 95% CI, 1.261-4.671; P=0.008). AF recurrence was associated with progressive TR and significant deterioration in right-sided heart remodeling.

CONCLUSIONS

In a retrospective PSM analysis, mitral valve disease with AF was associated with TR progression as well as right-sided heart remodeling, which are alleviated by surgical ablation.