Cardiac MR finds signature of broken heart syndrome

The shock of a surprise party or the loss of a loved one may not be the trigger of chest pain that sends grandma off to the hospital for emergency cardiac catheterization. The cause may not be heart attack at all but rather broken heart syndrome, also known as Tako-Tsubo cardiomyopathy, an increasingly common disease that can be diagnosed with cardiac MR.

Speaking at the 2006 RSNA meeting, staff radiologist Dr. Bernd Cornelius described the unique MR signature of Tako-Tsubo syndrome based on his experience with cases at the Hospital of the City of Ludwighafen am Rhein in Germany. Seven elderly women arrived at the hospital's emergency room in an eight-month period with acute chest pain and ECG changes. Troponin-T enzyme was elevated in five cases. Emergency coronary angiography was negative in all cases and led to referrals to MR.

MR was performed two to five days after onset of symptoms. Sequences included wall motion, first-pass perfusion with a steady-state free-precession, TRUFI, and delayed-enhancement with a Siemens-designed phase-sensitive inversion recovery protocol. From the delayed-enhancement images, Cornelius found that the myocardium appeared more gray than white in the left ventricular area. Apical ballooning and edema were also characteristic of the syndrome.

The grayish presentation did not appear in the first-pass images of the Tako-Tsubo cases. It was also absent on the first-pass and delayed-enhancement images of 66 patients who did not have broken heart syndrome despite fitting the social profile of the disease.

The ability to rule out myocardial infarction and myocarditis using the MR indicator is important, because it potentially spares elderly patients drug treatment for myocardial infarction, Cornelius said.

Tako-Tsubo cardiomyopathy derives its name from similarities between the distorted shape of the myocardium in patients with the condition and an octopus trap in use in Japan when Dr. H. Sato first described the disease in 1990. It is also generically referred to as transient left ventricular apical ballooning.

Research from Johns Hopkins University published in the Feb. 10, 2005, issue of The New England Journal of Medicine explained why elderly women under stress are susceptible. The study by assistant professor of cardiology Dr. Ilan Wittstein found that the symptoms of broken heart syndrome are caused by a surge of cathecholamines-especially epinephrine and norepinephrine-released after sudden, overwhelming emotional stress. The enzymes temporarily stun the heart, causing signs and symptoms similar to myocardial infarction: chest pain, pulmonary edema, shortness of breath, and depressed left ventricular ejection fraction.

The Johns Hopkins study also found that a characteristic ventricular contraction pattern appears during echocardiography. While the base of the left ventricle contracts normally, weakened contractions appear in the middle and upper portions of the muscle. A distinctive pattern also appears on electrocardiogram.

Though classified as rare, Tako-Tsubo cardiomyopathy has increased in incidence. Two radiologists who attended Cornelius' presentation had seen patients with the characteristic delayed-enhancement pattern of Taku-Tsubo in the previous two weeks.