Warning sign recognition may increase sudden cardiac arrest survival
In the 4 weeks before a sudden cardiac arrest, men and women frequently experience warning signs that, if responded to, could increase chance of survival, according to new study findings published in the Annals of Internal Medicine.
Because survival from sudden cardiac arrest is low, researchers conducted a prospective, population-based study (2002-2012) to assess symptoms in patients in the 4 weeks before sudden cardiac arrest to determine whether preventive strategies could improve survival rates.
Using the Oregon SUDS Sudden Unexpected Death Study (Oregon SUDS), researchers gathered data on symptoms and clinical history of both decedents and survivors (aged 35-65 years) of sudden cardiac arrest in the Portland, Oregon, metropolitan area. Symptoms were classified as chest pain (typical and atypical); dyspnea; palpitations; syncope; or other (abdominal pain, nausea, vomiting, back pain).
After excluding those patients for whom symptom assessment was not possible, 839 patients with sudden cardiac arrest were included in the final analysis. Of those, 51% experienced warning symptoms within the 4 weeks leading up to sudden cardiac arrest (50% of men vs. 53% of women; P = .59), but only 19% reported their symptoms by calling emergency medical services. The most common symptoms were chest pain (46%) and dyspnea (18%). In 93% of patients who experienced symptoms, the symptoms were recurrent within the 24 hours before sudden cardiac arrest occurred.
Most patients who called EMS before sudden cardiac arrest had a history of heart disease (P < .001) or were experiencing continuous chest pain (P < .001). These patients also were older (P = .021). Overall, the rate of survival was 32.1% (95% CI, 21.8-42.4) among patients who called in their symptoms before sudden cardiac arrest compared with 6% among those who did not report their symptoms (P < .001).
Although previous research has suggested that many women do not exhibit symptoms before sudden cardiac arrest, which can make prevention more challenging, the researchers found in this study that the number of symptomatic women and men were similar. However, men and women differed in the type of symptoms before sudden cardiac arrest. According to the researchers’ data, men were more likely to experience chest pain and women were more likely to experience dyspnea.
Sumeet S. Chugh, MD
“Now that we realize that sudden death may not be so sudden, there is also potential for new shorter-term approaches by increasing awareness and education of patients and their health care providers,” Sumeet S. Chugh, MD, medical director of the Heart Rhythm Center and the Harold Price Chair in Cardiac Electrophysiology Research at Cedars-Sinai Heart Institute, said in a press release. – by Tracey Romero
Disclosure: Chugh reports receiving grants from the Bettencourt Schueller Foundation, French Society of Cardiology Foundation for Medical Research, NHLBI and Philip Foundation outside of this study. The other researchers report no relevant financial disclosures.