Prognostic factors of atrial fibrillation following elective coronary artery bypass grafting: the impact of quantified intraoperative myocardial ischemia.

BACKGROUND: Atrial fibrillation (AF) occurs in 28-33% of the patients undergoing coronary artery revascularization (CABG). This study focuses on both pre- and peri-operative factors that may affect the occurrence of AF. The aim is to identify those patients at higher risk to develop AF after CABG. PATIENTS AND METHODS: Two patient cohorts undergoing CABG were retrospectively studied. The first group (group A) consisted of 157 patients presenting AF after elective CABG. The second group (group B) consisted of 191 patients without AF postoperatively. RESULTS: Preoperative factors presenting significant correlation with the incidence of post-operative AF included: 1) age > 65 years (p = 0.029), 2) history of AF (p = 0.022), 3) chronic obstructive pulmonary disease (p = 0.008), 4) left ventricular dysfunction with ejection fraction < 40% (p = 0.015) and 5) proximal lesion of the right coronary artery (p = 0.023). The intraoperative factors that appeared to have significant correlation with the occurrence of postoperative AF were: 1) CPB-time > 120 minutes (p = 0.011), 2) myocardial ischemia index < 0.27 ml.m2/Kg.min (p = 0.011), 3) total positive fluid-balance during ICU-stay (p < 0.001), 4) FiO2/PO2 > 0, 4 after extubation and during the ICU-stay (p = 0.021), 5) inotropic support with doses 15-30 µg/Kg/min (p = 0.016), 6) long ICU-stay recovery for any reason (p < 0.001) and perioperative myocardial infarction (p < 0.001). CONCLUSIONS: Our results suggest that the incidence of post-CABG atrial fibrillation can be predicted by specific preoperative and intraoperative measures. The intraoperative myocardial ischemia can be sufficiently quantified by the myocardial ischemia index. For those patients at risk we would suggest an early postoperative precautionary anti-arrhythmic treatment.

Stented within a stentless aortic valve. A simple surgical solution for the replacement of a stentless aortic bioprosthesis.

Stentless aortic bioprostheses are designed to offer better hemodynamics, less mechanical stress to the leaflets and as a result less degeneration. Although encouraging results are reported, little evidence has been published regarding reoperations of stentless valves. We are reporting a case of a structural valve dysfunction of an O'Brien-Angell stentless prosthesis, which could not be extracted during reoperation without damaging the aortic root. We are presenting a simple, quick and effective surgical solution, the surgical 'valve within a valve' technique for the avoidance of a redo complex root procedure.