From the Guidelines
The need for a permanent pacemaker after mitral valve repair due to bradycardia occurs in approximately 1-3% of patients, with the most recent guidelines recommending permanent pacing before discharge in patients with new postoperative sinoatrial node dysfunction or atrioventricular block associated with persistent symptoms or hemodynamic instability 1. This complication is relatively uncommon but represents an important consideration when planning mitral valve procedures. The risk increases with certain factors including advanced age, pre-existing conduction abnormalities, extensive calcification of the mitral annulus, and procedures involving the posterior annulus near the atrioventricular node. Some key points to consider include:
- Temporary bradycardia is more common in the immediate post-operative period but typically resolves without permanent pacing.
- When permanent pacemaker implantation is required, it usually occurs within the first week after surgery, with a recommended timing of 5 to 7 days after mitral valve surgery 1.
- The mechanism involves surgical trauma or edema affecting the conduction system, particularly when procedures involve manipulation near the atrioventricular node or bundle of His.
- Patients should be monitored closely for bradycardia symptoms including fatigue, dizziness, or syncope following mitral valve repair, as prompt recognition allows for timely intervention if permanent pacing becomes necessary. The American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society recommend permanent pacing in patients with new postoperative sinoatrial node dysfunction or atrioventricular block associated with persistent symptoms or hemodynamic instability after mitral valve repair or replacement surgery 1.
From the Research
Pacemaker Implantation after Mitral Valve Repair
- The need for pacemaker implantation after mitral valve repair is a significant concern, with studies indicating that a substantial number of patients require pacemakers due to bradyarrhythmias 2, 3, 4.
- According to a study published in 2021, approximately 10% of patients (80 out of 797) required pacemaker implantation for bradyarrhythmia after mitral valve surgery, with a cumulative rate of 6.4% at 50 days 2.
- Another study published in 2022 found that 7.6% of patients (2820 out of 37,124) required a permanent pacemaker implantation after mitral valve replacement, with post-MVR atrioventricular block being the most common indication 3.
- A 2024 study reported that 9.6% of patients (36 out of 401) required pacemaker implantation within 2 years of randomization, with 16.0% of patients in the mitral valve surgery + tricuspid annuloplasty group requiring pacemakers compared to 3.2% in the mitral valve surgery alone group 4.
Risk Factors for Pacemaker Implantation
- Mitral valve replacement and tricuspid ring annuloplasty have been identified as significant operative risk factors for pacemaker requirement after mitral valve surgery 2, 4.
- Insulin-dependent diabetes mellitus has also been identified as a predictor of pacemaker requirement 2.
- Age, male gender, pre-existing comorbid conditions, prior CABG, history of arrhythmias or using antiarrhythmic drugs, atrial fibrillation ablation, and double valve replacement have been reported as predictors of pacemaker implantation post-mitral valve replacement 3.
- Concomitant tricuspid annuloplasty, age, and baseline left ventricular ejection fraction have been associated with pacemaker implantation in patients who underwent mitral valve surgery for degenerative mitral regurgitation 4.
Indications for Pacemaker Implantation
- Post-mitral valve replacement atrioventricular block is the most commonly observed indication for pacemaker implantation, followed by sinoatrial node dysfunction and bradycardia 3.
- Most pacemaker implantations occur within 30 days postoperatively, with 80.6% of implantations occurring within this timeframe in one study 4.