No abstract

BackgroundRenal impairment is one of the predictors of mortality in cardiac surgery. Usually a binarized value of serum creatinine is used to assess the renal function in risk models. Creatinine clearance can be easily estimated by the Cockcroft and Gault equation from serum creatinine, gender, age and body weight. In this work we examine whether this estimation of the glomerular filtration rate can advantageously replace the serum creatinine in the EuroSCORE preoperative risk assessment.MethodsIn a group of 8138 patients out of a total of 11878 patients, who underwent cardiac surgery in our hospital between January 1996 and July 2002, the 18 standard EuroSCORE parameters could retrospectively be determined and logistic regression analysis performed. In all patients scored, creatinine clearance was calculated according to Cockcroft and Gault. The relationship between the predicted and observed 30-days mortality was evaluated in systematically selected intervals of creatinine clearance and significance values computed by employing Monte Carlo methods. Afterwards, risk scoring was performed using a continuous or a categorical value of creatinine clearance instead of serum creatinine. The predictive ability of several risk score models and the individual contribution of their predictor variables were studied using ROC curve analysis.ResultsThe comparison between the expected and observed 30-days mortalities, which were determined in different intervals of creatinine clearance, revealed the best threshold value of 55 ml/min. A significantly higher 30-days mortality was observed below this threshold and vice versa (both with p < 0.001). The local adaptation of the EuroSCORE is better than the standard EuroSCORE and was further improved by replacing serum creatinine (SC) by creatinine clearance (CC). Differential ROC analysis revealed that CC is superior to SC in providing predictive power within the logistic regression. Variable rank comparison identified CC as the best single variable predictor, even better than the variable age, former number 1, and SC, previously number 9 in the standard set of EuroSCORE variables.ConclusionThe renal function is an important determinant of mortality in heart surgery. This risk factor is not well captured in the standard EuroSCORE risk evaluation system. Our study shows that creatinine clearance, calculated according to the Cockcroft and Gault equation, should be applied to estimate the preoperative renal function instead of serum creatinine. This predictor variable replacement gains a significant improvement in the predictive accuracy of the scoring model.

Rupture of the left ventricular free wall is one of the most serious complications of myocardial infarction. A 73-year-old man with severe chest pain visited our hospital. Coronary angiography revealed acute myocardial infarction in the territory of the diagonal branch. About six hours after successful percutaneous coronary intervention, the patient fell into cardiogenic shock with chest pain. Echocardiography showed moderate pericardial effusion with a subepicardial hematoma, and percardioentesis led to the diagnosis of free wall rupture. Emergency surgery was performed with the use of intra-aortic balloon pumping. The rupture was a blowout type in a small tear at the anterolateral wall of the left ventricle. We repaired the tear with an off-pump sutureless patch using collagen fleece with fibrinogen-based impregnation (TachoComb) and equinous pericardium with fibrin spray. The patient was free of both re-rupture and pseudoaneurysm postoperatively, and was discharged 20 days after the operation. Considering previously reported various procedures for surgical repair, this technique may be useful if the tear is small.

BackgroundThe proportion of older patients in cardiac surgery is continuously increasing. 37% of patients undergoing heart surgery in Germany in the year 2000 were 70 years of age and older. We have studied the role of age as a determinant of mortality in cardiac surgery in our institutional patient population.MethodsWe have calculated the EuroSCORE and the corresponding age-adjusted EuroSCORE in 8769 patients who underwent heart surgery between January 1996 and January 2002 and collected the information on the occurrence of postoperative complications and 30-days mortality.ResultsThe multimorbidity increased with ascending age. Both the EuroSCORE and the age-adjusted EuroSCORE values increased significantly with age in the whole group of patients as well as in the group of patients who were alive 30 days after heart surgery. The incidence of postoperative complications and 30-days mortality increased significantly with age. In patients who died within 30 days after surgery, the EuroSCORE increased significantly with age, whereas the age-adjusted EuroSCORE did not. The occurrence of diabetes mellitus, arterial hypertension and atrial fibrillation, i.e., the risk factors not considered by the EuroSCORE, exhibited a significant age dependence in our patients. The univariate analysis identified the significant dependence of 30-days mortality on diabetes and atrial fibrillation. The stepwise logistic regression analysis showed the dependence of mortality on diabetes.ConclusionsOn the background of the well-known age-dependent structural and functional changes of different body organs, our data show that age is a significant risk indicator in cardiac surgery, strongly correlating with morbidity and mortality. Consequently, special preventive and therapeutic measures are required in clinical environment in the case of elderly patients undergoing cardiac surgery.

As the average age of patients undergoing cardiac surgery is increasing, the effects of age on the incidence of postoperative complications and 30-day mortality after coronary artery bypass grafting were examined. The EuroSCORE and corresponding age-stripped EuroSCORE were calculated in 6,057 patients who underwent isolated coronary bypass between January 1996 and January 2002. Both EuroSCORE and age-stripped EuroSCORE exhibited a significant increase with age in the whole group of patients and in those who were alive 30 days after surgery. The 30-day mortality and the incidence of postoperative complications increased significantly with age. A significant age-dependent increase in EuroSCORE was found in patients who died within 30 days postoperatively, whereas no age dependence was observed in the age-stripped EuroSCORE. Univariate analysis showed diabetes mellitus and atrial fibrillation to be significant risk factors for 30-day mortality; atrial fibrillation was also found to significantly affect 30-day mortality on multivariate analysis. In view of the increasing co-morbidity and age-dependent organ changes in the elderly, specific preventive and therapeutic measures are needed in this group of patients undergoing cardiac surgery.