7 vs. 16.6 atm, p = 0.014, respectively). As shown in Table 4, the atrial branch diameter, presence of atherosclerotic plaque at the ostium of atrial branches and maximal inflation pressure during stenting emerged as predictors of ABO in the multivariate analyses. However, none of the factors related to the procedure (predilatation, postdilatation, type, platform, strut thickness, cell design, length and diameter CB-839 supplier of stent, AB diameter, AB ostial atherosclerotic plaque, bifurcation lesion) or dyslipidemia or diabetes mellitus reached statistical significance. The ROC curve

(Fig. 2) showed that an atrial branch diameter cut-off value of 1.00 mm had a sensitivity of 77% and a specificity of 67.5% to predict ABO after elective PTCA (p ≤ 0.0001). This study reveals that accidental occlusion of atrial coronary branches occurred rather frequently in patients submitted to elective PTCA of the right or circumflex coronary arteries in an experienced coronary interventional center. Data also indicated that this complication is more frequent in patients with atrial branches of less than 1.00 mm in diameter, and occurred see more when this vessel is affected by ostial atherosclerosis and when higher

maximal inflation pressure during stenting is applied. Blood supply to the atrial myocardial in humans is afforded by vessels arising from the right and circumflex coronary arteries [18]. Our study is concordant with this description as it shows that more than 90% of our patients had atrial branches arising from both the right and circumflex coronary arteries. Likewise, we also observed that the arteries supplying the sinus and AV nodes originate in most instances from the right coronary artery. Knowledge of the magnitude of atrial branch diameter in a series of normal subjects is not presently available, but our study indicates that the mean

atrial branch diameter in patients with ischemic heart disease is about 1.23 mm (SD 0.34) thus highlighting the concept that these vessels should not be overlooked. The prevalence of atherosclerotic involvement of the atrial arteries is not well known, but this study shows that 45% Farnesyltransferase of our patients had appreciable atherosclerotic disease in the origin of the atrial branches. The incidence of accidental occlusion of atrial branches after PTCA has not been systematically analyzed. A few case-report studies [19] and [20] have afforded limited information and a study by Kotoku et al. [4] in 80 patients submitted to elective PTCA of the proximal right coronary artery revealed that 17.5% of cases presented an occlusion of the sinus node artery leading to transient sinus node dysfunction in some patients. Our study shows that 21.5% of patients undergoing elective PTCA presented accidental occlusion of atrial branches with a comparable incidence whenever the right or the circumflex coronary arteries were treated (22% and 20%, respectively).