Prevalence of coronary artery disease in patients with symptomatic conduction blocks requiring permanent pacemaker implantation
Background: Patients undergoing permanent pacing are not routinely investigated for coronary artery disease (CAD). This study aims to diagnose the potential CAD in patients admitted with symptomatic conduction blocks who may be at risk of CAD but are not admitted for ischemic symptoms.
Subjects and Methods: This cross-sectional study included 111 symptomatic conduction block non-acute coronary syndrome (N-ACS) patients and had 2 or more conventional risk factors of CAD (family history, diabetes, hypertension, smoking, and dyslipidemia) presented to emergency department in Punjab Institute of cardiology Lahore, Pakistan. All these patients underwent conventional coronary angiogram and coronary anatomy was analyzed by two independent cardiologists.
Results: Mean age of patients was 57.99±10.85 years, 76 (68.5%) were males and 35 (31.5%) females. Hypertension was most common risk factor observed in 101 (91%) patients followed by smoking 51 (45.9%), diabetes 47 (42.3%), family history of CAD 20 (18%) and dyslipidemia 19 (17.1%). Complete heart block was the most common conduction defect found in 87 (78.4%) patients. Among 111 patients, 49 (44.1%) had significant CAD, 20 (18.0%) had non-obstructive CAD and 42 (37.8%) had normal angiograms. Among obstructive CAD, left anterior descending (LAD) artery (73.4%) was the most common involved vessel followed by right coronary artery (RCA) (61.2%), left circumflex artery (LCX) (53.1%) and left main coronary artery (8.2%). Obstructive CAD group was further analyzed according to Mosseri`s classification as 5 (10.2%) Type I, 12 (24.5%) Type II, 09 (18.4 %) Type III and 23 (46.9%) had Type IV coronary anatomy. Significant correlation of diabetes (p = 0.005) and dyslipidemia (p = 0.001) was observed with CAD.
Conclusion: Among patients with symptomatic conduction blocks and multiple CAD risk factors, coronary artery disease on angiography is present in significant population. It supports the coronary evaluation as pre-permanent pacemaker (PPM) workup in these patients at high risk of CAD.