Distribution of coronary artery lesions in patients with permanent pacemakers.

Abstract

In the present study we examined retrospectively the coronary anatomy pathology of 78 consecutive patients with coronary artery disease (CAD) who underwent permanent pacemaker implantation in order to find a common pathological anatomic basis for conduction disturbances and to compare them with a group of matched patients with angiographically proven CAD. Study group consists of seventy-eight patients with angiographically documented CAD and permanent pacemaker implantation. Control group included comparable patients with CAD and without a pacemaker implantation. Coronary angiography was performed using standard Judkins approach in all patients within 2 months before pacemaker implantation. The locations of narrowings in the left anterior descending (LAD) and right (RCA) coronary arteries, as the arteries supplying the conduction system, were documented accurately and further classified as follows. Type I: Anatomy not compromising blood supply to the conduction system, namely, either the absence of significant narrowing in the LAD, RCA, left circumflex, posterolateral, or posterior descending arteries or the presence of mid-distal LAD lesions beyond the septal branches. Type II: Pathological coronary anatomy involving septal branches emerging from the LAD (and without significant lesions in the RCA). Type III: Pathological coronary anatomy compromising blood supply to the sinoatrial (SAN) or atrioventricular (AVN) nodes but not compromising blood flow to the septal branches. This subset included patients with distal LAD lesions after the septal branches. Type IV: Combination of types II and III pathological coronary anatomy that compromises blood supply both to the septal branches and SAN and AVN arteries. Occurrence of the type IV coronary anatomy (45%) was significantly higher than type I (19%), type II(24%) and type III (11%) in the study group (p<0.02). Statistically significant differences were found between the two groups (p<0.05): more patients in the study group had type II (24%) and IV(45%) coronary anatomy (p<0.02) while type I (35%) and III (37%) anatomy were more frequently observed in control group (p<0.05). Analysis of flow quality of septal perforators, SAN and AVN arteries, in the study group demonstrated a significant tendency for reduced blood flow in the conduction system. Presence of first perforator lesions with poor quality of flow and right coronary artery lesions shown angiographically should be considered as the risk factors requiring permanent pacemaker implantation in patients with coronary artery disease.