Stress Cardiomyopathy June 27, 2009 Henry Green, MD, FACC, FACP Definition Stress cardiomyopathy is an acute cardiomyopathy of unknown etiology. It has been called the apical ballooning syndrome and nick-named the “broken heart syndrome.” Another popular term the tako-tsubu syndrome because of the resemblance of the left ventriculogram to the Japanese fishing pot of the same name. Incidence 90-95% of cases occur in women, usually in the older age group. The average age in one group was 66. However it can occur in much younger women, e.g. age 32. It usually follows an emotional trauma, often grief, divorce, death of a child or a spouse, or some other life-changing event. It may also follow a medical problem, such as worsening of lung disease or a cholecystectomy. Its occurrence in pheochromocytoma suggests the possibility of a catecholamine-induced cardiomyopathy. Other hyperadrenergic states, such as subarachnoid hemorrhage tend to support this view. It has also been reported with sepsis, Guillain-Barre syndrome, non-cardiac surgery and various critical illnesses. Proposed etiology The condition has been attributed to epicardial spasm. This is probably unlikely, since these patients do not have inducible spasm, and the condition usually does not recur. It has been suspected of representing a variant of myocardial infarction, but the area of injury does not conform to the distribution of a coronary vessel. Another possibility is catecholamine toxicity. High levels of neurohormones have been documented in these patients, levels that exceed those ordinarily found in myocardial infarction of comparable severity. Catecholamines could induce epicardial or microvascular vasospasm or possibly directly injure myocytes. Clinical Symptoms The predominant symptom is chest pain that closely mimics that of a myocardial infarction. 10% present with a cardiac arrest that can be due either to ventricular fibrillation or asystole. Other presentations can occur, such as dyspnea, nausea, or vomiting. Sometimes it is discovered by finding an abnormal ECG or troponin level that was done for another reason. Electrocardiogram The ECG looks like an acute anterior myocardial infarction with ST segment elevation in V2-V6. The QT interval is often prolonged. Biomarkers The cardiac enzymes are mildly increased

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Coronary angiography Coronary angiography is mandatory, since the condition is otherwise indistinguishable from an acute ST elevation myocardial infarction. Indeed, if angiography is not available, the patient would appropriately be given thrombolytic therapy because of this uncertainty. Angiography usually shows very little obstruction of the epicardial vessels. What narrowing there is probably relates to the patient’s age. There is reduced TIMI flow, however. Ventriculography is characteristic. The entire distal 2/3 of the ventricle is akinetic, ballooning outward in systole. The base is usually hyperkinetic. The result is a very characteristic appearance referred to as apical ballooning, and often a significant left ventricular outflow tract obstruction. Course The condition acts a great deal like myocardial stunning. One third recover by the time of hospital discharge. In the remainder, left ventricular function is usually regained over the next few weeks or months. The cardiomyopathy may recur in as many as 15% of patients. 30% develop significant hypotension with a blood pressure under 90. 20% need an intraaortic balloon pump. Apical thrombi are common, and embolism can result. Left ventricular failure is sometimes seen. Ventricular arrhythmias may occur, as may mitral regurgitation and rupture of the free wall of the left ventricle. 1% of cases are fatal. Treatment If left ventricular outflow tract obstruction is seen, the use of beta-blockers and calcium channel blockers can be beneficial by slowing the heart and thus aiding diastolic filling. Avoid inotropes as they may worsen injury. In addition, they increase contractility of the outflow tract, aggravating systolic anterior motion of the mitral valve and adding to the outflow tract obstruction. One should use the intra-aortic balloon pump if there is significant hypotension. If the patient has persistent left ventricular dysfunction, the use of ACE inhibitors or ARB’s and diuretics is helpful. These can be discontinued when left ventricular function has returned to normal. Beta-blocking drugs are given at some institutions and continued after discharge with the hope of preventing recurrences. Coumadin should be administered, and continued until wall motion has returned to normal. Followup echocardiography is indicated. References Virani SS et al. Takotsubo Cardiomyopathy, or Broken-Heart Syndrome Tex Heart Inst J. 2007; 34: 76–79.

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Girod JP et al. Tako-Tsubo–Like Transient Left Ventricular Dysfunction. Circulation 2003; 107:e120 Cherian J et al. Atypical Takotsubo Cardiomyopathy. Tex Heart Inst J 2008; 35:73-75 Azeem L et al. Broken Heart Syndrome: Tako-tsubo Cardiomyopathy. Canadian Medical Association Journal 2009; 180:1033-1034 Sharkey SW et al. Acute and Reversible Cardiomyopathy Provoked by Stress in Women From the United States. Circulation 2005;111:472-479 Wittstein IS et al. Neurohumoral Features of Myoardial Stunning Due to Sudden Emotional Stress. N Engl J Med 2005; 352:539-548

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