Acute episodes of anger may cause potentially fatal heart rhythm disturbances, researchers reported at the American Heart Association’s Scientific Sessions 2006.
Electrocardiographic data called electrograms from implantable cardioverter defibrillators, or ICDs, were used to gather evidence to support the researchers’ conclusion. ICDs monitor and record the electrical activity of a patient’s heart and deliver a shock to correct certain life-threatening arrhythmias.
“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.”
Researchers enrolled 1,188 patients with ICDs in a two-year study at more than 30 medical centers around the United States. Patients were asked about their lifestyle habits and medical histories. They were also asked 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 experience and their emotions before the shock. Researchers then reviewed stored electrograms made by the patients’ ICDs before and during the event. This information was used to determine if 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, 15 (7.5 percent) were preceded by at least moderate levels of anger within the hour before ICD discharge.
“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 had weaker hearts, recently had their ICDs implanted or had received previous shocks from the devices.
The shocks, while necessary for survival, are painful and psychologically disturbing to patients who have ICDs, researchers said. Several other studies also suggest that patients who get frequent shocks 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.”
Co-authors are: Rachel Lampert, M.D.; Jamie B. Conti, M.D.; Mina K. Chung, M.D.; Paul J. Wang, M.D.; James E. Muller, M.D., M.P.H.; and Murray A. Mittleman, M.D., M.P.H.
The study was funded by the National Heart, Lung and Blood Institute, and by the Guidant Foundation, Guidant Cardiac Rhythm Management.