“Prior studies have shown that anger affects the heart’s electrical properties, making it more vulnerable to dangerous rhythm disturbances,” said Christine M. Albert, M.D., M.P.H., 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 ICDs, 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.”
A two-year study at more than 30 medical centers around the U.S. involved 1,188 patients with ICDs. Those patients were asked about their lifestyle habits, medical histories and 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 that their ICD delivered a shock. They were also asked to fill out a questionnaire about their experiences and their emotions before the shock. Researchers then reviewed stored electrograms made by the patients’ ICDs before and during the episodes. This information was used to determine if the study participants were more likely to experience a life-threatening arrhythmia 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 (VF) or ventricular tachycardia (VT), conditions that are fatal if not treated with a shock within minutes. Of the 199 shocks, 7.5 percent were preceded by at least moderate levels of anger within the hour before the ICD shock.
“We found that it was 3.2 times more likely for VF or VT to develop (prompting a shock from the ICD) 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 ICD shock for these life-threatening rhythm disturbances.”
Researchers also found that the patients who were most vulnerable to developing VF or VT coinciding with anger in general had weaker hearts, recently had their ICDs implanted or they had received previous shocks from the devices.
Researchers indicate that the shocks, while necessary for survival, are painful and psychologically disturbing to patients who have ICDs. Several other studies also suggest that patients who get frequent shocks from the ICDs have poorer prognoses than those who get fewer shocks from their 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 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.”