Prevalence of angiographically recognizable atherosclerosis in non-dominant right coronary arteries.

Among 1,000 consecutive patients referred for coronary arteriography because of chest pain, 89 patients were found to have a non-dominant right coronary artery (NDRCA). These patients were compared to 89 consecutive patients with dominant right coronary artery (DRCA) matched for age, sex, smoking and serum cholesterol. There was a lower incidence of obstructive disease in NDRCA (23 of 89 patients, 26%) than in DRCA (55 of 89 patients, 62%), X2 = 23.368, p less than 0.001. The incidence of coronary disease was also lower in the NDRCA group, 50 of 89 patients (56%), than in the DRCA group, 68 of 89 patients (76%), X2 = 8.146, p less than 0.01. When only patients with coronary artery disease (CAD) were included in the analysis: 23 of 50 (46%) patients with CAD and NDRCA had obstructive disease in the right coronary artery (RCA) while 55 of 68 (80%) patients with DRCA and CAD had obstructive disease in the RCA, X2 = 15.646, p less than 0.001. The lower incidence of disease in NDRCA persisted even when only the proximal one-third of the DRCA was considered: 41 of 89 (46%) patients with DRCA had proximal lesions compared to the total length of NDRCA, 23 of 89 patients (26%), X2 = 7.940, p less than 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)