Takotsubo Cardiomyopathy – The Broken Heart Syndrome
By Amy Chircop,
Reviewer: Dr. Justine Farrugia Preca
First described by Sato et al. in 1990 in Japan, Takotsubo Cardiomyopathy (TCM) is a cardiac phenomenon where the patient presents with features of acute coronary syndrome in the absence of obstructive coronary artery disease1.
Although not frequently encountered, TCM may be responsible for up to1-2% of admission for acute coronary syndromes in industrialised countries2. Patients present mainly with abrupt onset of chest pain and dyspnoea, and are admitted to hospital where a workup for acute coronary syndrome is usually started. In the majority of patients with TCM, initial investigations point towards an ischemic event, with characteristic ECG changes such as ST segment elevation and T wave inversion, further supported with increased cardiac biomarkers: Troponin T and Troponin I3. However, on echocardiography, there is characteristic hypokinesia or akinesia of mid-segment and apex of the left ventricle extending beyond the distribution of any single coronary artery (See Fig 1). This is confirmed by a coronary angiography which shows intact coronary arteries and characteristic apical ballooning, and a left ventriculography which shows characteristic wall motion and reduced ejection fraction4. Guidelines have been developed by Kawai et al. which give 4 diagnostic criteria which the patient must meet in order to be diagnosed with TCM5. These include:
- Transient hypokinesia, dyskinesia, or akinesia of the left ventricular mid-segments, with or without apical involvement; the regional wall-motion abnormalities extend beyond a single epicardial vascular distribution, and a stressful trigger is often, but not always, present
- Absence of obstructive coronary disease or angiographic evidence of acute plaque rupture
- New electrocardiographic abnormalities (either ST-segment elevation and/or T-wave inversion) or modest elevation in cardiac troponin level
- Absence of pheochromocytoma or myocarditis
The aetiology of TCM has been linked to multivessel coronary artery spasm, impaired cardiac microvascular function, impaired myocardial fatty acid metabolism, acute coronary syndrome with reperfusion injury, and endogenous catecholamine-induced myocardial stunning and microinfarction6. The vast majority of cases have been reported to occur after a severely stressful or emotional event or else with other physical stressors such as trauma, surgery, severe hypoglycemia or asthma; events which result in a high surge of adrenaline release. In fact, studies have shown that patients diagnosed with TCM have a higher level of cathecholamines than patients with myocardial infarction7. The apex of the left ventricle has the highest portion of sympathetic innervation hence this might explain why this phenomenon predominantly affects this region of the heart8.
The greater number of patients diagnosed with TCM are post-menopausal women, and interestingly a study by Pilgrim et al. done in 2008 found that patients with TCM have a lower incidence of cardiac risk factors such as hypertension, hyperlipidemia and diabetes4. TCM is a transient condition and left ventricular function is regained within 7 to 37 days. Initial management should be that for acute coronary syndrome due to the identical presentation and due to the fact that initial investigations are unable to differentiate between the two9. If the patient is haemodynamically unstable, then intra-aortic balloon pump counterpulsation is recommended. There are no current randomized control trials about the chronic management of TCM, however treatment with beta-blockers appears beneficial by preventing excessive sympathetic activation10.
References
1. Satoh H, Tateishi H, Uchida T, Dote K, Ishihara M. Takotsubo-type cardiomyopathy due to multivessel spasm. Clinical Aspect of Myocardial Injury: From Ischemia to Heart Failure. Tokyo: Kagakuhyouronsya Co., 1990: 56-64.
2. Banning AP. Takotsubo Cardiomyopathy. BMJ 2010; 340:1272
3. Jain SKA, Larsen TR, Sougiyyeh A, David SW. Takotsubo cardiomyopathy: reversible stress-induced cardiac insult- a stress protective mechanism. Am J Cardiovasc Dis. 2013; 3(1):53-59.
4. Pilgrim TM, Wyss TR. Takotsubo cardiomyopathy or transient left ventricular apical ballooning syndrome: A systematic review. Int J Cardiol. 2008; 124 (3):283-292.
5. Kawai S, Kitabatake A, Tomoike H. Guidelines for diagnosis of takotsubo (ampulla) cardiomyopathy. Circ J. 2007;71(6)990-992
6. Afonso L, Bachour K, Awad K, Sandidge G. Takotsubo Cardiomyopathy: pathogenic insights and myocardial perfusion kinetics using myocardial contrast echocardiography. Eur J Echocardiogr. 2008; 9(6):849-854.
7. Buchholz S, Rudan G. Tako-tsubo syndrome on the rise: a review of the current literature. Postgrad Med J. 2007;83(978):261-264.
8. Dorfman TA, Iskandrian AE. Takotsubo cardiomyopathy: State-of-the-art review. J Nucl Cardiol. 2009;16(1):122-134
9. Kolkebeck TE, Contant CL, Krasuski RA. Takotsubo cardiomyopathy: an unusual syndrome mimicking an ST- elevation myocardial infarction. Am J Emerg Med. 2007;25(1):92-95.
10. Palacek T, Kuchynka P, Linhart A. Treatment of Takotsubo cardiomyopathy. Current Pharm Des. 2010; 16(26):2905-2909.