Derivation and validation of a new score to predict long-term survival after sudden cardiac arrest.

BACKGROUND: There is insufficient information about the long-term prognosis of sudden cardiac arrest (SCA) survivors. We therefore derived a clinical score (Sudden Cardiac Arrest-mortality score, SCA-MS) that predicts long-term mortality in patients surviving to hospital discharge and validated it in an independent cohort of SCA survivors. METHODS: A total of 1433 SCA survivors data were collected, who were discharged from the hospitals of the University of Pittsburgh Medical Center between 2002 and 2012. The overall cohort was randomly divided into two near equal cohorts used for the derivation and validation of the SCA-MS, respectively. RESULTS: The derivation cohort included 768 patients and identified serum potassium level>4.2 mg/dL at admission, the presence of atrial fibrillation at any time during the index hospitalization, and the presence of asystole or pulseless electrical activity as the initial documented rhythm as independent predictors of long-term mortality. Based on the multivariable modeling result, one point was assigned to each one of these variables to create the SCA-MS that ranged from 0 to 3. In the validation cohort, the SCA-MS was predictive of long-term mortality (hazards ratio = 1.69, 95% confidence interval 1.50-1.91, P < 0.001) per 1-point increment in the SCA-MS. CONCLUSIONS: We describe a new clinical score that predicts long-term survival after SCA based on serum potassium levels at the admission, presence of atrial fibrillation, and documented rhythm of SCA.

Gender Differences in Cardiac Resynchronization Therapy Device Choice and Outcome in Patients ≥75 Years of Age with Heart Failure.

Cardiac resynchronization therapy (CRT) is an established therapy for heart failure and can be delivered through a CRT pacemaker (CRT-P) or a CRT defibrillator (CRT-D). CRT-P devices are smaller and less expensive, have better battery longevity, and have been subject to fewer recalls and advisories but cannot deliver high-energy shocks to terminate potentially lethal ventricular arrhythmias. As published guidelines do not distinguish between CRT-P and CRT-D indications, we examined the practice of prescribing these devices in older women and men with heart failure. A total of 512 CRT recipients (age ≥75 years, 26% women, 21% CRT-P) were included in this analysis. Baseline characteristics were collected on all patients, and overall survival was compared by gender and type of CRT device implanted. Women were more likely to receive CRT-Ps than men (26% vs 19%). Men with CRT-Ps were significantly older than women with CRT-Ps and both men and women with CRT-Ds (p = 0.04). In addition, women had lower all-cause mortality compared with men (hazard ratio [HR] 0.75, confidence interval [CI] 0.58 to 0.99, p = 0.04), mainly among CRT-P recipients (HR 0.48, CI 0.26 to 0.8, p = 0.02), but this association was attenuated after adjusting for differences in patient characteristics (HR 0.56, CI 0.26 to 1.18, p = 0.13). In conclusion, women are more likely to receive CRT-Ps than men. Whether this difference is driven by patient preference or physician biases remains unclear. Women with CRT, particularly CRT-Ps, have a better overall survival than men. These differences, which may be driven by unbalanced baseline characteristics of patients or by differences in gender response to CRT, deserve further investigation.