Takotsubo Cardiomyopathy

NORD gratefully acknowledges Etienne Leveille, MD Candidate, McGill University School of Medicine, and Leslie T. Cooper Jr., MD, Chair, Cardiovascular Department, Mayo Clinic in Florida, Professor of Medicine, Mayo Clinic, for assistance in the preparation of this report.
Synonyms of Takotsubo Cardiomyopathy
takotsubo syndrome
broken heart syndrome
stress cardiomyopathy
ampulla cardiomyopathy
apical ballooning syndrome

General Discussion

Summary
Takotsubo cardiomyopathy is a heart disease characterized by transient dysfunction and ballooning of the left ventricle of the heart. It mostly affects elderly women and is often triggered by severe physical or emotional stress. The symptoms are similar to those of a heart attack (myocardial infarction) and include chest pain, difficulty breathing (dyspnea), and sometimes transient loss of consciousness (syncope). Although complications can occur, most individuals fully recover within one month. The treatment of takotsubo cardiomyopathy is focused on symptom control and the prevention and treatment of associated complications.

Introduction
The role of the heart is to act as a pump to make sure blood is appropriately oxygenated and able to feed the body. The heart as four chambers: two small atria (left and right), which are located on top of the heart, and two larger ventricles (also left and right), which are located below the atria and act as the main pump of the heart. Blood flows in the body the following way: 1) Blood in the left ventricle is ejected into the aorta, which redistributes oxygenated blood throughout the body 2) Oxygen in the blood is extracted by organs and deoxygenated blood comes back in the right atrium of the heart via the veins 3) Deoxygenated blood in the right atrium falls into the right ventricle 3) Deoxygenated blood is ejected from the right ventricle into the pulmonary arteries, where it will be able to take oxygen from the lungs 4) Oxygenated blood comes back to the left atrium via the pulmonary veins 5) Oxygenated blood in the left atrium falls into the left ventricle of the heart, where the cycle can start again.

Takotsubo cardiomyopathy is a type of disease of cardiac muscle (cardiomyopathy) that is characterized by dysfunction and ballooning of a portion of the left ventricle of the heart, most often its tip (apex). It was first identified in Japan in the 1990s and was named after Japanese octopus traps (takotsubo) that are shaped similarly to the heart of affected individuals. Since that time, the condition has been recognized in individuals all over the world.

Takotsubo cardiomyopathy can occur in adults of any age, but most often develops in elderly women. The most common symptoms are the abrupt (acute) onset of crushing chest pain and difficulty breathing (dyspnea). Anxiety, sweating (diaphoresis), nausea, vomiting, palpitations, and transient loss of consciousness (syncope) can also occur.
Most individuals that develop takotsubo cardiomyopathy fully recover within one month, and recurrence is rare. However, complications occur in about 20% of patients. In some individuals, the heart might be unable to pump blood efficiently (heart failure), which can lead to fatigue, dyspnea, and leg and abdomen swelling due to fluid accumulation (edema). In severe cases, cardiac dysfunction might prevent organs from receiving adequate oxygen supply (cardiogenic shock). Takotsubo cardiomyopathy can also lead to an irregular, too fast, or too slow heartbeat (arrhythmia). Another possible complication is pooling of blood in the heart, which promotes clot formation. These clots can be expulsed from the heart and lodge into arteries of the brain, which can lead to a stroke. Despite the possibility of complications, more than 90% of affected individuals survive takotsubo cardiomyopathy.

Causes
The mechanism by which takotsubo cardiomyopathy develops in not entirely understood. In about 2/3 of cases, the disease is preceded by intense emotional stress (such as divorce, death of a loved one, or bankruptcy) or physical stress (such as a stroke, fracture, or infection). A hypothesis is that these stressors lead to the release of large amounts of adrenaline (epinephrine) and other stress-related hormones collectively known as catecholamines. This surge of hormones might lead to spasms of the blood vessels and disruption of the ventricles of the heart, which would be responsible for the ventricular dysfunction and ballooning seen in takotsubo cardiomyopathy.

Affected Populations
Takotsubo cardiomyopathy can develop in men and women of any age and ethnic background. However, about 90% of affected individuals are women, and 80% are women over the age of 50. The exact frequency of the disease is not known and might be underestimated, but is thought to comprise approximately 2% of all individuals (and up to 5% of women) with suspected ST-segment elevation myocardial infarction, which is the most severe type of heart attack. This represents more than 4000 individuals in the United States.

Related Disorders
Angina is a condition caused by limitation of blood flow to the heart. It is usually caused by partial obstruction of the arteries that feed the heart (coronary arteries) by a fatty plaque (atheroma), but can also rarely be caused by spasms of the arteries (vasospastic angina). Angina is usually triggered by exercise or stress and is relieved by rest, except in the case of vasospastic angina, which occurs at rest. The main symptom of angina is chest pain, which patients usually describe as a squeezing, pressure, or tightness. It is often accompanied by difficulty breathing (dyspnea), sweating (diaphoresis), nausea, and anxiety. Angina that occurs at rest, lasts longer than before, becomes more frequent, or becomes more intense is known as unstable angina.

Acute myocardial infarction (MI) also called heart attack, often progresses from angina and is characterized by a total or almost total obstruction of a coronary artery, most commonly by a blood clot (thrombus) that forms after rupture of a fatty plaque. The clinical presentation of acute MI is undistinguishable from takotsubo cardiomyopathy and includes crushing chest pain, difficulty breathing (dyspnea), sweating (diaphoresis), nausea, and anxiety. As acute MI is a much more common condition than takotsubo cardiomyopathy, diagnostic testing (described in the following section) has to be performed to exclude the possibility of a myocardial infarction in all patients presenting with the symptoms described above.

Myocarditis is a rare cause of cardiovascular disease that primarily manifests as sudden death, chest pain or heart failure. The symptoms of myocarditis are not specific to the disease and are similar to symptoms of more common heart disorders. A sensation of tightness or squeezing in the chest that is present with rest and with exertion is common. The cause of myocarditis is an inflammation of the heart muscle, most often following a viral infection. (For more information on this disorder, choose “myocarditis” as your search term in the Rare Disease Database.)

Pheochromocytoma is a rare type of tumor that arises from certain cells known as chromaffin cells, which produce hormones necessary for the body to function properly. Most pheochromocytomas originate in one of the two adrenal glands located above the kidneys in the back of the upper abdomen. Symptoms associated with pheochromocytomas occur because of the release of catecholamines. Symptoms include high blood pressure (hypertension), pain in the chest or abdomen, nausea, vomiting, diarrhea, constipation, pallor, weakness, and weight loss. In addition, some cases of a takotsubo-like cardiomyopathy have been reported in individuals with a pheochromocytoma. (For more information on this disorder, choose “pheochromocytoma” as your search term in the Rare Disease Database.)

Diagnosis

Typically, individuals with takotsubo cardiomyopathy present with symptoms undistinguishable from a myocardial infarction and will therefore be considered to have a heart attack until proven otherwise. The two most common and useful initial tests for an individual with symptoms suggesting an acute MI is an electrocardiogram (ECG), which measures electrical activity of the heart, and blood troponin levels, which is a marker of damage to the heart. In takotsubo cardiomyopathy, the ECG shows changes that are typically seen in a ST-segment elevation myocardial infarction (the most severe type of heart attack), and troponin levels are elevated, as they also are in an MI. However, when coronary angiography (a medical imagining technique in which a dye is injected into the coronary arteries to visualize them with radiographs) is performed in individuals with takotsubo cardiomyopathy, no significant coronary artery occlusion is seen. Ventricular dysfunction and ballooning can be identified with ventriculography (which uses the same principles as coronary angiography but allows visualization of the ventricles), or echocardiography (which uses ultrasound waves to make visualization of the heart possible). Cardiac magnetic resonance imaging (MRI) is a specialized imaging technique that can occasionally be used to diagnose takotsubo cardiomyopathy and assess the extent of ventricular dysfunction and ballooning.

Standard Therapies

Treatment & Management
Although there is no standard treatment for takotsubo cardiomyopathy, most individuals fully recover within 1 month. Research has shown that the use of angiotensin-converting–enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARB), which are two class of medication used to treat high blood pressure, might improve survival after the condition has resolved. Many patients are prescribed beta-blockers, a class of medication that decreases the activating effects of catecholamines on the heart. However, there is no scientific evidence proving the use of beta-blockers improves survival in takotsubo cardiomyopathy.
The management of the disease is mostly centered on symptom control and prevention and treatment of associated complications (supportive therapy). Patients that develop heart failure are usually treated with medication that stimulate the production of urine to eliminate excess fluid (diuretics) and medication that dilate blood vessels (vasodilators) to decrease the blood pressure the heart has to pump against. Fluid resuscitation might be required in those that develop cardiogenic shock. In some patients, blood thinners (anticoagulants) might be administered to prevent the formation of blood clots (thrombus). Pain control and addressing emotional and physical stressors that might have played a role in the development of the condition are two other important factors to consider.

Investigational Therapies
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Toll-free: (800) 411-1222TTY: (866) 411-1010Email: prpl@cc.nih.gov