Prediction of postoperative atrial fibrillation after coronary artery bypass grafting surgery: is CHA 2 DS 2 -VASc score useful?

AIMS AND OBJECTIVES: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass grafting (CABG) surgery. The identification of patients at risk for POAF would be helpful to guide prophylactic therapy. Presently, there is no simple preoperative scoring system available to predict patients at higher risk of POAF. In a retrospective observational study, we evaluated the usefulness of CHA 2 DS 2 -VASc score to predict POAF after CABG. MATERIALS AND METHODS: After obtaining approval from Institutional Review Board, 729 patients undergoing CABG on cardiopulmonary bypass (CPB) were enrolled. Patients were followed in the postoperative period for POAF. A multiple regression analysis was run to predict POAF from various variables. The area under the receiver operating characteristic (ROC) curve was calculated to test discriminatory power of CHA 2 DS 2 -VASc score to predict POAF. RESULTS: POAF occurred in 95 (13%) patients. The patients with POAF had higher CHA 2 DS 2 -VASc scores than those without POAF (4.09 ± 0.90 vs. 2.31 ± 1.21; P < 0.001). The POAF rates after cardiac surgery increased with increasing CHA 2 DS 2 -VASc scores. The odds ratio for predicting POAF was highest with higher CHA 2 DS 2 -VASc scores (3.68). When ROC curve was calculated for the CHA 2 DS 2 -VASc scores, area of 0.87 was obtained, which was statistically significant (P < 0.0001). CONCLUSIONS: The CHA 2 DS 2 -VASc score was found useful in predicting POAF after CABG. This scoring system is simple and convenient to use in the preoperative period to alert the clinician about higher probability of POAF after CABG surgery.

Management of patients with hematological malignancies undergoing coronary artery bypass grafting.

The number of patients with a previously diagnosed malignancy who need cardiac surgery is increasing. Patients with hematological malignancies represent only 0.38% of all patients undergoing cardiac surgery. The literature in this subset of patients is limited to only a few retrospective case series, with limited number of patients undergoing emergency cardiac surgery. We describe three cases with hematological malignancies namely chronic myelogenous leukemia, acute promyelocytic leukemia and chronic lymphocytic leukemia presenting for coronary artery bypass grafting (CABG). Two patients were taken up for emergency CABG in view of ongoing ischemia, one of them was on preoperative intra-aortic balloon pump support. No mortality was observed. Two patients needed transfusion of blood products which was guided by thromboelastography. One patient developed superficial sternal wound infection requiring antibiotic therapy.

The application of European system for cardiac operative risk evaluation II (EuroSCORE II) and Society of Thoracic Surgeons (STS) risk-score for risk stratification in Indian patients undergoing cardiac surgery.

AIMS AND OBJECTIVES: To validate European system for cardiac operative risk evaluation II (EuroSCORE II) and Society of Thoracic Surgeons (STS) risk-score for predicting mortality and STS risk-score for predicting morbidity in Indian patients after cardiac surgery. MATERIALS AND METHODS: EuroSCORE II and STS risk-scores were obtained pre-operatively for 498 consecutive patients. The patients were followed for mortality and various morbidities. The calibration of the scoring systems was assessed using Hosmer-Lemeshow test. The discriminative capacity was estimated by area under receiver operating characteristic (ROC) curves. RESULTS: The mortality was 1.6%. For EuroSCORE II and STS risk-score C-statics of 5.43 and 6.11 were obtained indicating satisfactory model fit for both the scores. Area under ROC was 0.69 and 0.65 for EuroSCORE II and STS risk-score with P values of 0.068 and 0.15, respectively, indicating poor discriminatory power. Good fit and discrimination was obtained for renal failure, long-stay in hospital, prolonged ventilator support and deep sternal wound infection but the scores failed in predicting risk of reoperation and stroke. Mortality risk was correctly estimated in low (< 2%) and moderate (2-5%) risk patients, but over-estimated in high-risk (> 5%) patients by both scoring systems. CONCLUSIONS: EuroSCORE II and STS risk-scores have satisfactory calibration power in Indian patients but their discriminatory power is poor. Mortality risk was over-estimated by both the scoring systems in high-risk patients. The present study highlights the need for forming a national database and formulating risk stratification tools to provide better quality care to cardiac surgical patients in India.