Catheter-induced Spasm in the Proximal Right Coronary Artery

Objectives The clinical characteristics in patients with catheter-induced spasm in the proximal right coronary artery (RCA) are controversial. We performed a clinical analysis of catheter-induced spasm in the RCA. Methods We retrospectively analyzed 5,296 consecutive patients who underwent diagnostic or follow-up angiography during a 26-year period. During this period, we found 40 patients with catheter-induced spasm in the RCA. We compared the clinical characteristics and procedures of cardiac catheterization in patients with catheter-induced spasm in the RCA with those in patients without such spasm. Results The frequency of catheter-induced spasm in the RCA was 0.75% (40/5,296). We performed pharmacological spasm provocation tests in 36 of 40 patients after spasm relief. Positive spasm was observed in 32 patients (88.9%), and 25 patients (78.1%) had multiple spasms. The catheter procedures, including the approach sites (radial/brachial/femoral), catheter size (4/5/6Fr) and catheter type (Judkins right/Sones/Shared/Judkins left 3.5/Amplatz) were not markedly different between the two groups. A multivariate analysis showed that positive spasm [odds ratio (OR): 7.030, 95% confidence interval (CI): 1.920-25.700], a younger age (OR: 0.937, 95% CI: 0.910-0.965) and diabetes mellitus (OR: 0.278, 95% CI: 0.083-0.928) were the determinant factors for the catheter-induced spasm. Conclusion Approximately 80% of patients with catheter-induced spasm in the proximal RCA had coronary spastic angina. Positive provoked spasm was the most powerful determinant factor for catheter-induced spasm.