Stress may trigger tear in large artery

NEW YORK (Reuters Health) - Severe physical or emotional stress may be the inciting events for sudden damage to the aorta, the body's largest artery, new research suggests. The underlying cause is likely to involve a sharp rise in blood pressure, which causes the tear.

High blood pressure (hypertension) and dilation (widening) of the arteries have been linked to a sudden tear in the artery, but the events immediately preceding the tear, also called a "dissection," have been unclear, according to the report in the American Journal of Cardiology. Aortic dissection is a potentially life-threatening condition in which there is bleeding into and along the wall of the aorta, the major artery leaving the heart.

Dr. John A. Elefteriades and colleagues, from Yale University School of Medicine in New Haven, Connecticut investigated physical and emotional stress as underlying factors by analyzing data from 175 consecutive patients with aortic dissection who were treated at their center over a 10-year period. In addition to performing a chart review, the researchers were able to conduct telephone interviews for 90 of the patients.

Sixty-five of the patients were women and the average age was 61 years, the report indicates. The ascending aorta was involved in 110 cases and the descending aorta in 65.

Of the 90 patients contacted by telephone, 65 could recall a specific inciting event, the researchers note. The ascending aorta was involved in 34 cases and the descending aorta in 31 cases. Eighteen of these patients had a family history of aortic disease.

Strenuous activity was identified as a precipitating factor for aortic dissection in 24 of the patients (27 percent) contacted. Severe emotional stress was identified as an inciting event in another 36 cases (40 percent).

About two thirds of patients were able to identify either severe exertion or severe emotion as a trigger for their acute aortic dissection," Elefteriades and colleagues note.

Three of the dissections were related to hospital care, the report indicates, and in two other patients, a flare-up in COPD, with heavy coughing, preceded the acute onset of chest pain.

The authors hypothesize that an individual's genetic background determines the initial susceptibility to aortic dissection. Over time, enzymes slowly degrade the aortic walls, possibly leading to aortic dilation. These factors set the stage for an acute physical or emotional stressor to trigger the dissection itself.

SOURCE: American Journal of Cardiology, October 2007.