[Clinical predictive factors of coronary artery stenosis located distally to myocardial bridging].

OBJECTIVE

To explore the clinical predictive factors of coronary artery stenosis located distally to myocardial bridging (MB).

METHODS

A total of 603 patients with MB-mural coronary artery (MB-MCA) diagnosed by angiography initially were enrolled during May 2004 to May 2009. Their angiographic and clinical data were collected according to an uniform protocol. And standard questionnaires were used to acquire demographic information and clinical examinations. Univariate and multivariate analysis were performed to explore the related clinical predictive factors.

RESULTS

A total of 644 MB-MCAs were detected. Diastolic vessel diameters in MCAs were significantly smaller than those in reference segments ( (2.29 ± 0.39) vs (2.48 ± 0.40) mm, P < 0.001) . Lesions located distally to MB detected in 36 patients were significantly fewer than those proximally to MB in 382 patients (5.9% vs 62.4%, P < 0.001) . Univariate analysis suggested that the narrowing degree of vessel located proximally to MB, the narrowing degree and the number of diseased coronary vessels of non-MB-MCAs and course of hypertension were positively correlated with the narrowing degree of vessel located distally to MB (all P < 0.05) . Multivariate Logistic regression analysis suggested that the number of cigarettes per day, the narrowing degree of diseased coronary vessels of non-MB-MCAs, the narrowing degree of vessel located proximally to MB and diastolic narrow rate of MCA were positively correlated with the occurrence of coronary artery stenosis located distally to MB (all P < 0.05) . Their standardized coefficients (β) were 0.763, 0.727, 0.420 and 0.403 respectively. And the corresponding Exp (β) were 2.146 (1.089-4.229) , 2.070 (1.371-3.125) , 1.521 (1.050-2.204) and 1.496 (1.094-2.045) .

CONCLUSION

The number of cigarettes per day, the narrowing degree of diseased coronary vessels of non-MB-MCAs, the narrowing degree of vessel located proximally to MB and diastolic narrowing rate of MCA are likely to be important clinical predictive factors of coronary artery stenosis located distally to MB.