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.

Two stage hybrid approach for complex aortic coarctation repair.

BACKGROUND: Management of an adult patient with aortic coarctation and an associated cardiac pathology poses a great surgical challenge since there are no standard guidelines for the therapy of such complex pathology. Debate exists not only on which lesion should be corrected first, but also upon the type and timing of the procedure. Surgery can be one- or two-staged. Both of these strategies are accomplice with elevate morbidity and mortality. CASE REPORT: In the face of such an extended surgical approach, balloon dilatation seems preferable for treatment of severe aortic coarctation.We present an adult male patient with aortic coarctation combined with ascending aorta aneurysm and concomitant aortic valve regurgitation. The aortic coarctation was corrected first, using percutaneous balloon dilatation; and in a second stage the aortic regurgitation and ascending aorta aneurysm was treated by Bentall procedure. The patients' postoperative period was uneventful. Three years after the operation he continues to do well.

Influence of ultra-low dose Aprotinin on thoracic surgical operations: a prospective randomized trial.

BACKGROUND: The blood saving effect of aprotinin has been well documented in cardiac surgery. In thoracic surgery, very few recent studies, using rather high doses of aprotinin, have shown a similar result. In a randomized prospective trial, we have tested the influence of aprotinin using an ultra-low dose drug regime. METHODS: Fifty-nine patients, mean age 58 +/- 13.25 years (mean +/- SD) undergoing general thoracic procedures were randomized into placebo (Group A) and treatment group (Group B). The group B (n = 29) received 500.000 IU of aprotinin after induction to anesthesia and a repeat dose immediately after chest closure. A detailed protocol with several laboratory parameters was recorded. Patients were transfused when perioperative Ht was less than 26%. RESULTS: The two groups were similar in terms of age, gender, diagnosis, pathology, co-morbidity and operations performed. The mean drainage of the first and second postoperative day in group B was significantly reduced (412.6 +/- 199.2 vs. 764.3 +/- 213.9 ml, p < 0.000, and 248.3 +/- 178.5 vs. 455.0 +/- 274.6, p < 0.001). Similarly, the need for fresh frozen plasma transfusion was lower in group B, p < 0.035. Both the operation time and the hospital stay were also less for group B but without reaching statistical significance (84.6 +/- 35.2 vs 101.2 +/- 52.45 min. and 5.8 +/- 1.6 vs 7.2 +/- 3.6 days respectively, p < 0.064). The overall transfusion rate did not differ significantly. No side effects of aprotinin were noted. CONCLUSION: The perioperative ultra-low dose aprotinin administration was associated with a reduction of total blood losses and blood product requirements. We therefore consider the use of aprotinin safe and effective in major thoracic surgery.

Ulcerated calcification of the interventricular septum causing transient ischemic attacks: case report.

BACKGROUND: Calcific deposits are frequently observed at sites of healed myocardial infarcts. Grossly visible calcification of myocardial infarcts and calcified intracavitary cardiac thrombi are less common but recently are becoming more frequent findings during surgical ventricular restoration procedures. CASE PRESENTATION: A 64 year old male diabetic patient experienced two episodes of transient ischemic attacks during the last six months. During the diagnostic work up he was found to have triple vessel coronary artery disease with mild left ventricular dysfunction, akinesia of the anterior-apical wall and hypokinesia of the inferior wall. He was referred to our department for coronary artery bypass grafting. He underwent elective triple coronary artery bypass and a ventricular restoration procedure due to apical wall thinning. The inspection of the left ventricle revealed an ulcerated round shape calcification of the interventricular septum with a crater filled with clot. We resected the above lesion and covered the damaged area with the septal Dacron patch of the modified linear closure. The patient was discharged from the hospital on the 11th postoperative day and has been doing well 6 months later, with improvement in both ventricular function and clinical status. CONCLUSION: The exploration of the left ventricular cavity reveals interesting phases of the post-infarction healing process. The suspicion of left ventricular thrombosis in patients with ventricular asynergy justifies a ventricular exploration during coronary artery bypass surgery.

In situ cooling in a lung hilar clamping model of ischemia-reperfusion injury.

Experimental models for studying transplantation have up to now been unable to isolate reperfusion injury with minimal surgical manipulation and without the interference of graft rejection. Six pigs were subjected to left hilum preparation only (control group), and eight pigs were subjected to left hilum preparation plus in situ cooling ischemia and reperfusion of the lung (experimental group). The hilum was dissected free from other tissues in both groups. Lung preservation was achieved by antegrade flush perfusion via the left pulmonary artery. Pulmonary veins were clamped at the left atrium and a vent was created. The left main bronchus was clamped. Lung temperature was maintained at 4 degrees -8 degrees C, while core temperature was kept at 38 degrees C. After 3 hrs of cold ischemia the clamps were removed and the lung was reperfused. Elevated pulmonary vascular resistance and local and systemic aspects of ischemia-reperfusion syndrome were consistently reproduced. This large-animal model of in situ unilateral lung cold ischemia with warm reperfusion proved to be very reliable in reproducing all aspects of ischemia-reperfusion injury. It excludes the interference of rejection and extensive surgical manipulation. We therefore propose its use in experimental studies investigating pharmaceutical or cooling modifications affecting lung ischemia-reperfusion outcomes.