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In recent years, there have been increasing reports of an acute cardiac phenomenon of transient acute left ventricular dysfunction precipitated by profound emotional or physiological stress. There are associated ECG abnormalities and myocardial injury as evidenced by modestly elevated cardiac markers without angiographic evidence of obstructive coronary disease.

Initial reports were from Japan. However, this phenomenon has been described in other parts of the world including Europe, the United States, Australia and Israel.

The phenomenon is known as tako-tsubo or stress-induced cardiomyopathy, apical ballooning syndrome and broken heart syndrome. Dote et al proposed the term ‘tako-tsubo’ in 1991. Tako-tsubo is a Japanese device or pot with a round bottom and narrow neck used for catching octopuses. This device is similar in appearance to the left ventricle in systole as seen during the left ventriculogram (LV gram) of patients with this condition. In the most common form, there is apical ballooning with characteristic akinesis to dyskinesis of the anteroapical and inferoapical segments with hyper-contractility of the basilar segments. Other segmental wall motion abnormalities have been reported.

The precise pathogenesis is unclear. However, there is evidence supporting the role of catecholamine excess leading to cardiac microvascular dysfunction, acute myocarditis and myocardial stunning somewhat analogous to the transient left ventricular dysfunction reported in the setting of acute brain injury. High plasma levels of catecholamines have been measured in both conditions suggesting a similarity in pathogenesis. Myocardial fatty acid metabolism has been shown to be significantly decreased compared with myocardial perfusion at the akinetic apical segments in patients with established tako-tsubo cardiomyopathy. This suggests the involvement of multivessel coronary microvascular dysfunction.

Reported triggers include events such as the death of a spouse, relative or close friend, catastrophic financial losses, and recent diagnoses of life-threatening illness or natural disasters.
The clinical characteristics described in the literature include:

• A large female predominance


•  Age greater than 60 years


• Acute emotional stressors


•  Abnormal ECG findings with ST segment elevation or depression usually in leads V3-V6. Prolonged QTc and Q waves have also been reported


•  Elevated cardiac biomarkers – albeit modestly so.


• Apical ballooning noted on left ventriculogram or echocardiography


• No angiographic evidence of obstructive coronary disease


• Recovery of normal myocardial function within several weeks


• Transient left ventricular outflow tract obstruction (LVOT) secondary to basilar hyper-contractility with systolic anterior motion of the mitral valve as seen in hypertrophic cardiomyopathy has also been reported.

Tako-tsubo cardiomyopathy is a diagnosis of exclusion. Thus, even if the condition is suspected in patients presenting with ST segment elevations, the standard of care for ST elevation myocardial injury should be adhered to - they should be taken to the cardiac catheterization laboratory or given thrombolytics unless contraindicated. A diagnosis should be made only in the absence of obstructive coronary disease with the previously mentioned associated features.

Tako-tsubo or stress-induced cardiomyopathy is a transient/reversible condition with a severe presentation. Most patients would recover their cardiac function in 1-4 weeks and only supportive or conservative management is required. Established medications for cardiomyopathies such as beta-blockers, ACE inhibitors or angiotensin receptor blockers, diuretics and aldosterone antagonists have been used. Aspirin and statins are also recommended. The role of Plavix or chronic anticoagulation with coumadin is questionable and should be used if there are other established indications.

Since the prognosis is favorable with prompt recovery, the duration of therapy is unclear. Occasional recurrence has been reported and some patients may require indefinite treatment. The four-year recurrence rate has been estimated at 11.4 percent after initial presentation. The four year survival is, however, not different from age-matched and gender-matched population. A diagnosis of underlying pheochromocytoma should be excluded.

Complications may include atrial or ventricular dysrhythmias, which should be managed accordingly. Severe conditions such as cardiogenic shock requiring pressors, inotropes (which are contraindicated in the presence of moderate to severe LVOT obstruction) and intra-aortic balloon pump support have been reported. More serious life-threatening albeit rare complications such as apical thrombus and ventricular rupture have also been reported and should be treated accordingly. Involvement of the right ventricle is not uncommon and this seems to portend a more severe impairment of the left ventricle.

In summary, tako-tsubo cardiomyopathy is an acute cardiac syndrome that is beginning to gain more recognition outside of Japan. It should be suspected in patients presenting with acute chest symptoms, modestly elevated cardiac enzymes, angiographically unremarkable coronary angiograms, apical ballooning noted during LV grams and characteristic features mentioned earlier. Although there can be significant cardiac complications, the prognosis is excellent and patients should be assured of this. Established therapy for cardiomyopathies should be instituted at least until recovery of cardiac function.
Recurrence has been reported and such patients should be treated indefinitely.

Dr. Linus A. Wodi attended the University of Lagos, College of Medicine in Nigeria. He is Board Certified in Internal Medicine, Cardiovascular Medicine and Nuclear Cardiology. He is a member of the American College of Cardiology and the American Society of Nuclear Cardiology. Dr. Wodi practices at the Orlando Heart Center’s downtown location.



July 2008

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