Complete Atrioventricular Block and Permanent Pacemaker Implantation Following Percutaneous Coronary Intervention to Left Anterior Descending Artery Chronic Total Occlusion

Area of Science:

• Cardiology
• Interventional Cardiology
• Electrophysiology

Background:

• Patients with pre-existing conduction abnormalities, such as first-degree atrioventricular block and left bundle branch block (LBBB), may be at higher risk during percutaneous coronary interventions.
• Chronic total occlusions (CTOs) in the left anterior descending (LAD) artery present unique challenges during revascularization.

Observation:

• A 72-year-old male with baseline conduction abnormalities underwent recanalization of a CTO LAD.
• Following the procedure, the patient developed persistent complete atrioventricular block, necessitating permanent pacemaker implantation.

Findings:

• The complication is speculated to be caused by occlusion of a septal branch artery supplying the His bundle's right branch.
• This suggests a potential vulnerability of the His bundle's blood supply during LAD interventions.

Implications:

• Elective interventions in the LAD territory require meticulous attention to preserving blood flow to septal perforator branches, especially in patients with baseline ECG abnormalities.
• Prompt restoration of flow to compromised septal arteries via wiring and balloon angioplasty should be considered if perfusion deteriorates during the procedure.