Acute episodes of anger may cause ventricular arrhythmias in susceptible people, according to a presentation at the annual meeting of the American Heart Association.

Data from implantable cardioverter-defibrillators were used along with self-reports to look for correlations between emotion and arrhythmia sufficient to trigger a shock. American researchers enrolled 1,188 patients with devices for the two-year study.

“Prior studies have shown that anger affects the heart’s electrical properties, making it more vulnerable to dangerous rhythm disturbances,” said Christine M. Albert, MD, MPH, lead author of the study and director of the Center for Arrhythmia Prevention at Brigham and Women’s Hospital in Boston, Mass. “Our Triggers of Ventricular Arrhythmia study examined this theory in a population of people who have implantable cardioverter-defibrillators, making it possible to look for a connection between a patient’s self-reported level of anger and the development of life-threatening heart rhythms.”

Patients were asked about lifestyle habits and medical histories, as well as how often they felt four levels of anger (mildly angry, moderately angry, very angry, and furious). Patients were told to call and report their experience any time a shock was delivered and were asked to fill out a questionnaire about experience and emotions before the shock. Researchers analyzed this information against electrograms recorded before and after an arrhythmia to see if ventricular arrhythmias were more likely within an hour of an episode of moderate (or greater) level of anger.

Researchers obtained interview data from patients after 271 events. In 199 of those cases, shocks were delivered in response to ventricular fibrillation or ventricular tachycardia. Of the 199 shocks, 15 (7.5 percent) were preceded by at least moderate levels of anger within the hour before device discharge.

“We found that it was 3.2 times more likely for ventricular fibrillation or tachycardia to develop (prompting a shock from the device) after the participant became at least moderately angry, as compared to periods of no anger,” Albert said. “If they were very angry, or furious, there was about a 16.7-fold increased risk of having the device shock for these life-threatening rhythm disturbances.”

Researchers also found that the patients who were most vulnerable to developing ventricular arrhythmias coinciding with anger had weaker hearts, recently had their devices implanted, or had received previous shocks from the devices.

“Doctors and their patients want to avoid these shocks,” Albert said. “Our results suggest that emotions, particularly anger, can trigger dangerous rhythm disturbances and implantable device (ICD) shocks. Hopefully, educating doctors, patients and family members about these risks may help to minimize how often the patient experiences anger, and counseling could be considered for patients who have received ICD shocks in conjunction with anger.”