25-year survival of patients with atherosclerotic non-obstructive coronary plaques

Background Atherosclerotic non-obstructive coronary artery disease (NobCAD) is frequently observed in patients referred for coronary angiography. No available data exist for the long-term prognosis of NobCAD patients beyond 20 years. Purpose The aim of our study was to compare the 15-, 20-and 25-year survival among 3 groups of patients (with smooth coronary arteries, NobCAD, and obstructive (ObCAD)) diagnosed by invasive coronary angiography due to suspected coronary artery disease. Methods Coronary angiographies of 671 consecutive patients presenting with suspected CAD were retrospectively evaluated from a single-center registry between January and December 1998 and linked to administrative databases for outcome evaluation. No CAD (group A), NobCAD (B), and ObCAD (C) were defined as 0%, 1% to 49%, and ≥50% luminal narrowing in the epicardial coronary artery. The 15- , 20-, and 25-year survival rates were compared using Kaplan-Meier curves, and multivariate Cox proportional hazards regression was utilized to identify significant independent predictors of mortality. Results Of 613 individuals (78.7% men, median age 60.1 years) 74 (12.1%) had normal coronary arteries, 42 (6.9%) had NobCAD, and 497 (81%) had ObCAD. The 15-year survival was 89% vs. 66.7% vs. 62.4%, 20-year survival 79.7% vs. 54.7% vs. 42,5% and the 25-year survival 56.8% vs. 33.3% vs. 21.7% in in patients with normal, NobCAD, and ObCAD, respectively, (P = 0.050 for normal versus NobCAD; P = 0.001 for normal versus ObCAD at 20-year).The angiographic severity categories showed a strong gradient in survival (P < 0.001) (Figure 1). At 25-year follow-up, patients with ObCAD had significantly higher mortality risk compared to the normal coronary arteries group (HR = 1.93, 95% CI: (1.314–2.829), p = 0.001), while those with NobCAD showed no significant difference (HR = 1.49, 95% CI: (0.884–2.500), p = 0.136). Age at admission remained an independent predictor of mortality (HR = 1.006, 95% CI: (1.005–1.007), P < 0.001). Conclusion Patients with more severe coronary atherosclerosis have significantly worse long-term prognosis. Presence of NobCAD carries a mortality risk higher to patients with normal coronary arteries. These findings support the need for aggressive anti-atherosclerotic drug therapy in such individuals and underscore the necessary efforts to improve the risk stratification and management of patients also in the early stages of atherosclerosis.