PURPOSE:Transient left ventricular apical ballooning syndrome or takotsubo cardiomyopathy (TC) is characterized by symptoms and electrocardiographic changes similar to acute myocardial infarction, in presences of non-obstructive coronaries.We describe six patients with LVABS to illustrate the clinical features and a possible cause of this transient left ventricular systolic dysfunction. These patients developed TC on exposure to exogenous catecholamines.
METHODS:This retrospective study was approved by Institutional Review Board. We reviewed six patients who were diagnosed with TC based on Mayo criteria. All patients underwent coronary angiography and serial echocardiography. Perfusion defects were assessed by Technetium Myoview SPECT imaging on presentation and during recovery.
RESULTS:All four cases (3 males, 3 females) (Median age 62 years) exhibited characteristic transient clinical, ECG and echocardiographic changes of TC. They were admitted with varied presentations including chest pain, pulmonary edema and cardiogenic shock requiring intra-aortic balloon counterpulsation (1 patient). Initial ECG showed sinus rhythm and ST & T abnormalities. Median peak Troponin I was 2.3 ng/ml.On echocardiography they had similar contractile pattern, with preserved basal function and apical and mid-ventricle akinesis. Median Ejection fraction of 0.20 at presentation improved to 0.55 six to ten days later with normal contractility of all segments. Angiography revealed non obstructive coronary arteries. All patients exhibited moderate to large size perfusion defect at apex after persantine infusion with partial to complete reversibility at rest. Perfusion defect decreased in size at one month duration in 5 patients and completely resolved at 6months (1 patient). Notably, all four were exposed to catecholamines (× agonist inhalers and dobutamine infusion during stress tests) immediately prior to developing regional wall motion abnormality.
CONCLUSION:Takotsubo cardiomyopathy is an important condition mimicking acute coronary syndromes but the pathogenesis remains unclear. Catecholamines (exogenous or endogenous) may be central to the cause of transient left ventricular apical ballooning syndrome. Transient perfusion defects in presences of normal coronaries may implicate catecholamine mediated microcirculatory dysfunction.
CLINICAL IMPLICATIONS:Catecholamines may play a central role in takotsubo cardiomyopathy.
DISCLOSURE:Shikha Sharma, No Financial Disclosure Information; No Product/Research Disclosure Information