Warning Symptoms Are Associated With Survival From Sudden Cardiac Arrest

Survival after sudden cardiac arrest (SCA) remains low, and tools for improved prediction of patients at long-term risk for SCA are lacking. Alternative short-term approaches aimed at preemptive risk stratification and prevention are needed.

To assess characteristics of symptoms in the 4 weeks before SCA and whether response to these symptoms is associated with better outcomes.

Ongoing prospective population-based study.

Northwestern United States (2002 to 2012).

Residents aged 35 to 65 years with SCA.

Assessment of symptoms in the 4 weeks preceding SCA and association with survival to hospital discharge.

Of 839 patients with SCA and comprehensive assessment of symptoms (mean age, 52.6 years [SD, 8]; 75% men), 430 (51%) had warning symptoms (50% of men vs. 53% of women; P = 0.59), mainly chest pain and dyspnea. In most symptomatic patients (93%), symptoms recurred within the 24 hours preceding SCA. Only 81 patients (19%) called emergency medical services (911) to report symptoms before SCA; these persons were more likely to be patients with a history of heart disease (P < 0.001) or continuous chest pain (P < 0.001). Survival when 911 was called in response to symptoms was 32.1% (95% CI, 21.8% to 42.4%) compared with 6.0% (CI, 3.5% to 8.5%) in those who did not call (P < 0.001).

Potential for recall and response bias, symptom assessment not available in 24% of patients, and missing data for some patients and SCA characteristics.

Warning symptoms frequently occur before SCA, but most are ignored. Emergent medical care was associated with survival in patients with symptoms, so new approaches are needed for short-term prevention of SCA.

National Heart, Lung, and Blood Institute.