Development and validation of a risk calculator for prediction of cardiac risk after surgery.

BACKGROUND: Perioperative myocardial infarction or cardiac arrest is associated with significant morbidity and mortality. The Revised Cardiac Risk Index is currently the most commonly used cardiac risk stratification tool; however, it has several limitations, one of which is its relatively low discriminative ability. The objective of the present study was to develop and validate a predictive cardiac risk calculator. METHODS AND RESULTS: Patients who underwent surgery were identified from the American College of Surgeons' 2007 National Surgical Quality Improvement Program database, a multicenter (>250 hospitals) prospective database. Of the 211 410 patients, 1371 (0.65%) developed perioperative myocardial infarction or cardiac arrest. On multivariate logistic regression analysis, 5 predictors of perioperative myocardial infarction or cardiac arrest were identified: type of surgery, dependent functional status, abnormal creatinine, American Society of Anesthesiologists' class, and increasing age. The risk model based on the 2007 data set was subsequently validated on the 2008 data set (n=257 385). The model performance was very similar between the 2007 and 2008 data sets, with C statistics (also known as area under the receiver operating characteristic curve) of 0.884 and 0.874, respectively. Application of the Revised Cardiac Risk Index to the 2008 National Surgical Quality Improvement Program data set yielded a relatively lower C statistic (0.747). The risk model was used to develop an interactive risk calculator. CONCLUSIONS: The cardiac risk calculator provides a risk estimate of perioperative myocardial infarction or cardiac arrest and is anticipated to simplify the informed consent process. Its predictive performance surpasses that of the Revised Cardiac Risk Index.

Intensive smoking cessation intervention reduces mortality in high-risk smokers with cardiovascular disease.

PURPOSES: To compare an intensive smoking cessation intervention against usual care in hospitalized high-risk smokers with acute cardiovascular disease. METHODS: A total of 209 hospitalized smokers were randomized to the intensive intervention (n = 109) or to usual care (n = 100). Usual care consisted only of counseling and printed educational material provided prior to hospital discharge. Intensive treatment consisted of a minimum of 12 weeks of behavior modification counseling and individualized pharmacotherapy provided at no cost to the participant. Smoking status in all subjects was confirmed biochemically (ie, by measuring expired carbon monoxide) at 3, 6, 12, and 24 months after randomization. Outcomes included point prevalence and continuous abstinence smoking cessation rates, hospitalizations, and all-cause mortality. RESULTS: At each follow-up interval, point prevalence and continuous abstinence smoking cessation rates were significantly greater in the intensive-treatment group compared to the usual-care group. At 24 months, continuous abstinence smoking cessation rates were 33% in the intensive-treatment group and 9% in the usual-care group (p < 0.0001). Over the 2-year follow-up period, 41 patients in the usual-care group were hospitalized compared to 25 patients in the intensive-treatment group (relative risk reduction [RRR], 44%; 95% confidence interval [CI], 16 to 63%; p = 0.007). The all-cause mortality rate was 2.8% in the intensive-treatment group and 12.0% in the usual-care group (RRR, 77%; 95% CI, 27 to 93%; p = 0.014). The absolute risk reduction in mortality was 9.2% with a number needed to treat of 11. CONCLUSION: Hospitalized smokers, especially those with cardiovascular disease, should undergo treatment with a structured intensive cessation intervention. The duration of the initial treatment should be 3 months.

Pharmacological management of atrial fibrillation following cardiac surgery.

Atrial fibrillation (AF) is the most common complication following coronary artery bypass graft surgery (CABG). Post-CABG AF occurs most commonly on the second postoperative day and declines in incidence thereafter. A number of risk factors have been found to be associated with a higher frequency of post-CABG AF. These risk factors include advanced age, a prior history of AF, hypertension, and heart failure. Postoperative complications--including low cardiac output, use of an intra-aortic balloon pump, pneumonia, and prolonged mechanical ventilation--are also associated with higher rates of post-CABG AF. Post-CABG AF increases the risk of stroke, and the length and cost of hospitalization. Prophylactic administration of conventional beta-adrenoceptor antagonists (beta-blockers) or sotalol produces a consistent and significant reduction in the incidence of post-CABG AF; however, results with prophylactic amiodarone or magnesium are less consistent. Termination of post-CABG AF, once it occurs, can be accomplished with a number of antiarrhythmic agents. Ibutilide has been the most widely studied agent for this indication. Sotalol is not indicated for cardioversion of AF and has not been studied in the post-CABG setting. Electrical cardioversion and biatrial pacing have also been used to terminate post-CABG AF. Ventricular rate is best controlled with beta-blockers and calcium channel antagonists. Esmolol has a rapid onset of action and is easily titrated to effect. Digoxin can control the ventricular rate, but has a slow onset of action. There are limited data available to guide decisions regarding the optimal management of post-CABG AF.