[Pre and perioperative factors determining early in-hospital mortality in patients over 75 years of age undergoing cardiac surgery]

Cirugía cardíaca en el anciano: nuevas perspectivas para una población en crecimiento

Improvement in socioeconomic and sanitary conditions during last 2 decades has lead to 4 year-life expectancy increasing in Spanish population. Increasing in age-related cardiovascular pathologies makes more necessary cardiac surgery in the elderly. Analysis of current characteristics of elderly population, cardiac surgery indications in this group, as well as morbimortality published results and future expectations, constitute the topic of this review.

[Aortic valve replacement in patients over 70 years old: determinants of early death]

INTRODUCTION AND OBJECTIVES

There is controversy regarding the risk factors associated with early death in geriatric patients undergoing aortic valve replacement. We analyzed the risks in these patients and established an accurate model for predicting in-hospital mortality.

PATIENTS AND METHOD

Univariate and multivariate analyses were made of the risk factors associated with early death in a group of 129 patients older than 70 years who underwent aortic valve replacement (May 1994-June 2001). The variables obtained by multivariate logistic regression were combined to produce an equation for the prediction of early death. The equation was tested using a receiver operating characteristic curve.

RESULTS

Univariate analysis identified four factors related to early death: NYHA III-IV (p < 0.0001), ejection fraction < 40% (p < 0.05), aortic regurgitation (p < 0.05) and high left ventricular mass index (p < 0.05). Multivariate analysis revealed three independent risk factors: NYHA III-IV (p < 0.01), aortic regurgitation (p < 0.05), and small body surface area (p < 0.05). A lower mortality was observed in patients with a larger body surface area (0% for > 1.90 m2, 20% for < 1.40 m2). The estimated mortality with the predictive model was 7.06%, which was similar to the observed mortality of 7.80% (area under the ROC curve 0.87) and better than estimates obtained with the EuroSCORE (6.5%; area under the ROC curve 0.56).

CONCLUSIONS

Risk factors associated with early death after aortic valve replacement in geriatric patients include functional status, aortic regurgitation, and small body surface area. Our model based on these factors accurately predicted operative mortality in our patients. Gender, prosthesis size, and pump time were not identified as risk factors.

[Cardiac surgery in elderly patients]

OBJECTIVE

The morbimortality of elderly patients, (age 70 years or older), who underwent surgery for valvular and coronary artery disease in the last 17 years was analyzed.

PATIENTS AND METHOD

A total of 1,305 patients (654 valvular, 531 coronary and 120 combined) operated from January 1985 to December 2000 were retrospectively studied. Mean age was 73.7 years. We analyzed the progression of the pathology, comorbidity, and results. A second retrospective analysis was made of patients who underwent surgery in the last three years (436 patients) to determine the relation between preoperative comorbidity and postoperative evolution.

RESULTS

The mean hospital mortality was 16% (18% valvular, 11% coronary artery, and 23% combined). In the last three years this mortality was reduced to 11% (15.17, 6.26, and 16.18%, respectively) despite an increase in comorbidity. Comorbidity and complications increased with age (p < 0.05). Mean hospital stay was 15.5 days and the stay in intensive/semi-intensive care was 5 days. Independent risk factors of postoperative complications were creatinine levels > 2 mg/dl, combined surgery, and prior surgery. Predictors of death were prior surgery, valvular surgery, and combined surgery, with a clear tendency in the case of obesity. The presence of any complication in the postoperative period (renal or respiratory failure, infections, or myocardial infarction) was an independent predictor of mortality. Off-pump coronary surgery reduced mortality. In recent years, the mortality of patients operated without extracorporeal circulation has decreased from 5.71% to 4% for those who underwent extracorporeal circulation.

CONCLUSIONS

Nowadays, cardiac surgery in older patients accounts for more than 30% of our surgical activity. Mortality is being controlled although comorbidity is increasing. The difference with respect to younger people is due to comorbidity (creatinine > 2 mg/dl, combined surgery, and previous surgery) and the higher probability of complications (infections, renal, and respiratory complications), which worsens prognosis. We believe that off-pump coronary surgery helps to improve results.