Perioperative risk of heart failure patients undergoing major noncardiac surgery

Over 10 million major non-cardiac surgical procedures were performed in the U.S. in 2000 There have been significant advances in the care of the perioperative patient undergoing non-cardiac surgery in the last two decades. These have primarily been aimed at the assessment and risk modification of those patients with coronary artery disease. Patients with heart failure (HF), however, represent an increasingly large and high risk population undergoing major non-cardiac surgery. HF is a major medical problem in the United States. There are over five million patients with HF in this country, and there are an estimated 555,000 new cases each year. The reason for the increasing incidence and prevalence of HF is likely multifactorial including improved therapies and survival of patients with chronic medical conditions such as atherosclerosis, hypertension, acute coronary syndromes and heart failure itself. Additionally, HF has a high prevalence among older individuals with 80% of cases occurring in patients 65 or older. Older individuals are undergoing major non-cardiac surgery at increasing rates with 4 million major non-cardiac procedures performed each year. Patients with HF are at significant risk for life threatening perioperative complications. There are several widely used risk indices as well as practice guidelines that recognize HF as an important risk factor for adverse outcomes in the perioperative period. Currently, the ACC/AHA guideline for the cardiovascular assessment of the patient undergoing non-cardiac surgery lists decompensated heart failure as a major clinical predictor and compensated or prior heart failure as an intermediate clinical predictor of poor outcome. Prior studies and recommendations have also recognized the importance of heart failure as a predictor of poor outcome in non-cardiac surgery. In 1977 Goldman, et al. published the original cardiac risk index for patients undergoing major non-cardiac surgery. Included in this index were clinical signs of heart failure including the presence of JVD or S3 gallop. In the Revised Cardiac Risk index HF remains as one of six important preoperative risk factors. The data available for the assessment of risk and prevention of perioperative complications remain limited. In an ongoing retrospective review of patients with heart failure who underwent intermediate to high risk non-cardiac surgery at our institution (n=134), 27% of patients had at least one perioperative event including death (7.5%), non ST-segment elevation MI (14.2%), ST elevation MI (1.2%), and HF exacerbations (21%). Advances in therapeutic and diagnostic modalities in the treatment of HF including medical therapy such as vasodilator therapy, beta adrenergic antagonism and neurohormonal blockade, as well as serum studies such as BNP may prove useful in the evaluation and prevention of cardiac risk in patients undergoing non-cardiac surgery. HF remains a clinical diagnosis, however B-type natriuretic peptide (BNP) levels have been shown to be useful in determining HF as a cause of dyspnea in patients presenting to the emergency room. Furthermore, high levels of plasma BNP have been correlated with morbidity and mortality in patients with asymptomatic or minimally symptomatic HF, and BNP levels vary largely within a population of patients with heart failure. The levels have not been evaluated with regard to non-cardiac surgery. Other clinical signs of decompensated cardiac failure such as the S3 gallop (used in the initial cardiac risk index) have been shown to have poor inter-observer agreement. Phonocardiography is considered the gold standard for detection of an S3 and is relatively simple to perform, but is generally not used in the assessment of patients with HF. Patients with HF represent an important and high risk group undergoing major non-cardiac surgery. Specific risk factors and novel indexes have not yet been developed to predict adverse outcomes in this cohort of patients. Furthermore, recent advances in the treatment and evaluation of patients with