STENOSIS OF THE RIGHT CORONARY-ARTERY AND RETROGRADE CARDIOPLEGIA PREDISPOSE PATIENTS TO ATRIAL-FIBRILLATION AFTER CORONARY-ARTERY BYPASS-GRAFTING

It is assumed that stenosis of the right coronary artery (RCA) predisp oses CABG patients, by way of incomplete atrial myocardial protection, to postoperative atrial fibrillation (AF). Sixty patients with high-g rade RCA lesion were randomized into four groups according to the tech nique of delivery of cold blood cardioplegia: antegrade, retrograde, r etrograde without catheter cuff, and combined antegrade and retrograde . As controls, 34 patients without RCA lesion were randomized to recei ve antegrade or retrograde cardioplegia. Postoperative atrial fibrilla tion episodes were recorded. Patients with RCA lesion were more prone to develop Ar; odds ratio (OR)= 3.75 (95% confidence interval [CI]= 1. 22-11.5). Retrograde delivery in these patients was more often associa ted with Ar, OR = 4.97 (95% CI = 1.02 - 24.1). Other risk factors for Ar were an increasing number of preoperative infarcts (p < 0.05) and m ore advanced coronary artery disease (p < 0.05). Prolonged stay in the intensive care unit (p < 0.001) and occurrence of postoperative ventr icular tachycardia (p < 0.05) were associated with AF. RCA stenosis an d retrograde cardioplegia delivery in RCA-affected patients were risk factors for postoperative atrial fibrillation. Retrograde cardioplegia may offer poorer protection at the atrial level.