Takotsubo cardiomyopathy

Takotsubo cardiomyopathy
Schematic representation of takotsubo cardiomyopathy (A) compared to a normal heart (B).
Classification and external resources
Specialty	Cardiology
ICD-10	I42.8
ICD-9-CM	429.83
DiseasesDB	33976
eMedicine	article/1513631
Patient UK	Takotsubo cardiomyopathy
MeSH	D054549

Takotsubo cardiomyopathy, also known as transient apical ballooning syndrome, apical ballooning cardiomyopathy, stress-induced cardiomyopathy, Gebrochenes-Herz-Syndrom, and stress cardiomyopathy is a type of non-ischemic cardiomyopathy in which there is a sudden temporary weakening of the muscular portion of the heart. Because this weakening can be triggered by emotional stress, such as the death of a loved one, a break-up, or constant anxiety, it is also known as broken-heart syndrome. Stress cardiomyopathy is a well-recognized cause of acute heart failure, lethal ventricular arrhythmias, and ventricular rupture.

Signs and symptoms

The typical presentation of takotsubo cardiomyopathy is a sudden onset of congestive heart failure associated with ECG changes mimicking a myocardial infarction of the anterior wall. During the course of evaluation of the patient, a bulging out of the left ventricular apex with a hypercontractile base of the left ventricle is often noted. It is the hallmark bulging out of the apex of the heart with preserved function of the base that earned the syndrome its name "tako tsubo", or octopus pot in Japan, where it was first described.

Stress is the main factor in takotsubo cardiomyopathy, with over 85% of cases are set in motion by either a physically or emotionally stressful event that prefaces the start of symptoms. Examples of emotional stressors may include grief from the death of a loved one, fear from public speaking, arguing with a spouse, relationship disagreements, betrayal or financial problems. Acute asthma, surgery, chemotherapy, and stroke are examples of physical stressors.

Takotsubo cardiomyopathy is more commonly seen in postmenopausal women. Often there is a history of a recent severe emotional or physical stress.

Causes

File:Takotubo akasi-si PC012375.jpg

The Japanese octopus traps after which this disease is named.

The cause of takotsubo cardiomyopathy is not fully understood, but several mechanisms have been proposed.

1. Wraparound LAD: The left anterior descending artery (LAD) supplies the anterior wall of the left ventricle in the majority of patients. If this artery also wraps around the apex of the heart, it may be responsible for blood supply to the apex and the inferior wall of the heart. Some researchers have noted a correlation between takotsubo and this type of LAD. Other researchers have shown that this anatomical variant is not common enough to explain takotsubo cardiomyopathy. This theory would also not explain documented variants where the midventricular walls or base of the heart does not contract (akinesis).
2. Transient vasospasm: Some of the original researchers of takotsubo suggested that multiple simultaneous spasms of coronary arteries could cause enough loss of blood flow to cause transient stunning of the myocardium. Other researchers have shown that vasospasm is much less common than initially thought. It has also been noted that when there are vasospasms, even in multiple arteries, that they do not correlate with the areas of myocardium that are not contracting.
3. Microvascular dysfunction: The theory gaining the most traction is that there is dysfunction of the coronary arteries at the level where they are no longer visible by coronary angiography. This could include microvascular vasospasm, however it may well also have some similarities to the diseases such as diabetes mellitus. In such disease conditions the microvascular arteries fail to provide adequate oxygen to the myocardium.
4. Mid-ventricular obstruction, apical stunning It has also been suggested that a mid-ventricular wall thickening with outflow obstruction is important in the pathophysiology.

It is likely that there are multiple factors at play which could include some amount of vasospasm, failure of the microvasculature, and an abnormal response to catecholamines (such as epinephrine and norepinephrine, released in response to stress).

Case series looking at large groups of patients report that some patients develop takotsubo cardiomyopathy after an emotional stress, while others have a preceding clinical stressor (such as an asthma attack or sudden illness). Roughly one third of patients have no preceding stressful event. A recent large case series from Europe found that takotsubo was slightly more frequent during the winter season. This may be related to two different possible/suspected pathophysiological causes: coronary spasms of microvessels, which are more prevalent in cold weather, and viral infections – such as Parvovirus B19 – which occur more frequently during the winter season.

Diagnosis

Transient apical ballooning syndrome or takotsubo cardiomyopathy is found in 1.7–2.2% of patients presenting with acute coronary syndrome. While the original case studies reported on individuals in Japan, takotsubo cardiomyopathy has been noted more recently in the United States and Western Europe. It is likely that the syndrome went previously undiagnosed before it was described in detail in the Japanese literature. Evaluation of individuals with takotsubo cardiomyopathy typically includes a coronary angiogram, which will not reveal any significant blockages that would cause the left ventricular dysfunction. Provided that the individual survives their initial presentation, the left ventricular function improves within 2 months.

The diagnosis of takotsubo cardiomyopathy may be difficult upon presentation. The ECG findings are often confused with those found during an acute anterior wall myocardial infarction. It classically mimics ST-segment elevation myocardial infarction, and is characterised by acute onset of transient ventricular apical wall motion abnormalities (ballooning) accompanied by chest pain, shortness of breath, ST-segment elevation, T-wave inversion or QT-interval prolongation on ECG. Elevation of myocardial enzymes is moderate at worst and there is absence of significant coronary artery disease.

The diagnosis is made by the pathognomonic wall motion abnormalities, in which the base of the left ventricle is contracting normally or is hyperkinetic while the remainder of the left ventricle is akinetic or dyskinetic. This is accompanied by the lack of significant coronary artery disease that would explain the wall motion abnormalities. Although apical ballooning has been classically described as the angiographic manifestation of takotsubo, it has been shown that left ventricular dysfunction in this syndrome includes not only the classic apical ballooning, but also different angiographic morphologies such as mid-ventricular ballooning and rarely local ballooning of other segments.

The ballooning patterns were classified by Shimizu et al. as takotsubo type for apical akinesia and basal hyperkinesia, reverse takotsubo for basal akinesia and apical hyperkinesia, mid-ventricular type for mid-ventricular ballooning accompanied by basal and apical hyperkinesia and localised type for any other segmental left ventricular ballooning with clinical characteristics of takotsubo-like left ventricular dysfunction.

Focal myocytolysis is reported as an origin of this cardiomyopathy. No microbiological agent has been associated so far with takotsubo cardiomyopathy. Kloner et al. reported that a pathologic change in the myocardium was not demonstrated in the stunned myocardium. Infiltration of small mononuclear cells has been documented in some cases; these pathologic findings suggest that this cardiomyopathy is a kind of inflammatory heart disease, but not a coronary heart disease. There is also a report describing histologic myocardial damage without coronary heart disease.

In short, the main criterion for the diagnosis of takotsubo cardiomyopathy are: the patient must have experienced a stressor before the symptoms began to arise; the patient’s ECG reading must show abnormalities from a normal heart; the patient must not show signs of coronary blockage or other common causes of heart troubles; the levels of cardiac enzymes in the heart must be elevated or irregular; and the patient must recover complete contraction and be functioning normally in a short amount of time.

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  Left ventriculography during systole showing apical ballooning akinesis with basal hyperkinesis in a characteristic takotsubo ventricle.

• Takotsubo left ventriculogram.jpg

  Left ventriculogram during systole displaying the characteristic apical ballooning with apical motionlessness in a patient with takotsubo cardiomyopathy.

• Takotsubo ultrasound.gif

  (A) Echocardiogram showing dilatation of the left ventricle in the acute phase. (B) Resolution of left ventricular function on repeat echocardiogram 6 days later.

• Takotsubo ECG.JPEG

  ECG showing sinus tachycardia and non-specific ST and T wave changes from a patient with confirmed takotsubo cardiomyopathy.

Treatment

The treatment of takotsubo cardiomyopathy is generally supportive in nature. Although patients with takotsubo heart disease may have low blood pressure, treatment with inotropes will usually exacerbate the disease. Since the disease is due to a high catecholamine state, patients should not be given inotropes. Treatment recommendations include intra-aortic balloon pump, fluids, and negative inotropes such as beta blockers or calcium channel blockers. In many individuals, left ventricular function normalizes within 2 months. Aspirin and other heart drugs also appear to help in the treatment of this disease, even in extreme cases. After the patient has been diagnosed, and myocardial infarction (heart attack) ruled out, the aspirin regimen can be discontinued, and treatment becomes that of supporting the patient.

While medical treatments are important to address the acute symptoms of takotsubo cardiomyopathy, further treatment includes lifestyle changes. It is important that the individual stay physically healthy, while learning and maintaining methods to manage stress, and cope with future difficult situations.

Prognosis

Despite the grave initial presentation in some of the patients, most of the patients survive the initial acute event, with a very low rate of in-hospital mortality or complications. The patients are expecting a favorable outcome once recovering from the acute stage of the syndrome, and the long-term prognosis is excellent. Even when ventricular systolic function is heavily compromised at presentation, it typically improves within the first few days and normalises within the first few months. Although infrequent, recurrence of the syndrome has been reported and seems to be associated with the nature of the trigger.

Epidemiology

Takotsubo cardiomyopathy is rare, affecting between 1.2% and 2.2% of people in Japan and 2% to 3% in western countries. It also affects far more women than men with 90% of cases being women, most menopausal. Scientists believe one reason is that estrogen causes the release of catecholamine and glucocorticoid in response to mental stress. It is not likely for the same recovered patient to experience the syndrome twice, though it has happened in rare cases. The average ages at onset are between 58 to 75 years. Less than 3% of cases occurred in patients under age 50.

History

Although the first case of takotsubo cardiomyopathy was not until the 1990s, Cebelin and Hirsch wrote about human stress cardiomyopathy in 1980. The two looked at homicidal assaults that had happened in Cuyahoga County, Ohio the past 30 years, specifically those with autopsies that had no internal injury but had died of physical assault. They found that 11 of 15 had myofibrillar degeneration similar to animal stress studies. In the end they concluded their data supported “the theory of catecholamine mediation of these myocardial changes in man and of the lethal potential of stress through its effect on the heart”.

The first studied case of takotsubo cardiomyopathy was in Japan in 1991 by Sato et al. More cases of the syndrome appeared in Japan within the next decade, though western medicine had still not heard of it. The syndrome finally occurred in 1997 when Pavin et al. wrote about two cases of “reversible LV dysfunction precipitated by acute emotional stress.” The western world had not heard of such a thing at the time as it was incredibly rare and often misdiagnosed. The Japanese at last reported about the syndrome to the west in 2001 under the name “transient LV apical ballooning” though at this point the west had already heard of numerous cases. The syndrome reached international audiences through the media in 2005 when the New England Journal of Medicine wrote about the syndrome.

External links

• Takotsubo website