From the Research
Pacemaker implantation for bradycardia in single ventricle infants should be considered when the heart rate is consistently below 70 beats per minute (bpm) during the day or below 60 bpm during sleep, especially if associated with symptoms or hemodynamic compromise. Specific criteria for pacemaker implantation include:
- Persistent bradycardia with a heart rate <70 bpm during waking hours
- Pauses in heart rhythm >3 seconds
- Symptoms associated with bradycardia (e.g., fatigue, poor feeding, syncope)
- Evidence of compromised cardiac output or circulatory instability Before proceeding with pacemaker implantation, other causes of bradycardia should be ruled out, including electrolyte imbalances, medication side effects, and hypothyroidism, as suggested by 1. The decision to implant a pacemaker should be made in consultation with a pediatric electrophysiologist and consider the infant's overall clinical status, stage of palliation, and potential risks of the procedure. Epicardial pacing is typically preferred in these infants due to their small size and complex anatomy, as seen in 2. The pacemaker settings should be optimized to maintain adequate heart rates while minimizing unnecessary pacing. Justification: Single ventricle infants have limited cardiac reserve and are particularly vulnerable to bradycardia, making it crucial to maintain an appropriate heart rate for ensuring adequate cardiac output and systemic perfusion in these patients with complex congenital heart disease, as highlighted by 3.