Scintigraphic imaging in Tako-Tsubo cardiomyopathy.

Tako-Tsubo cardiomyopathy (TTC, stress cardiomyopathy) is more common in elderly women and its symptoms can be deceptively similar to those of acute myocardial infarction. Although coronary arteries appear normal on coronary angiograms, a shape like a Tako-Tsubo (a Japanese fishing pot for trapping octopuses) can be observed on left ventriculogram. TTC is generally considered to be a trigger for sudden cardiac death. The onset mechanism of TTC is still controversial. Catecholamine cardiotoxicity and/or coronary circulation disturbance due to coronary microvascular spasm and/or neurogenic stunned myocardium as a result of autonomic imbalance are considered to be the most likely causes. In this review, we assess the usefulness of myocardial scintigraphic imaging in TTC patients on the basis of the results obtained from earlier studies and case reports in order to establish a deeper understanding of the pathophysiological mechanism of this syndrome.

Cardiac autonomic imbalance in patients with reversible ventricular dysfunction takotsubo cardiomyopathy.

BACKGROUND: Although in reversible takotsubo cardiomyopathy (TC), wall motion generally recovers dramatically within a few weeks, there are few data on changes in autonomic function in this condition. AIM: To investigate cardiac autonomic function in the acute and chronic phases of TC. METHODS: Ten patients with TC (mean age 70.1 +/- 13.7 years) underwent cardiac catheterization on the first hospital day, when left ventricular (LV) ejection fraction (EF) was calculated. A Holter electrocardiographic study was performed within 3 days after the onset of symptoms (0 months) and 3 months after discharge (3 months). The standard deviation of the mean cycle length of normal-normal R-R (NN) intervals over 24 h (SDNN), and the 24-h standard deviation of the mean value of the difference between the NN intervals for each 5-min segment (SDANN), were calculated according to time-area analysis of heart rate variability over 24 h. Frequency domain analysis was also done. RESULTS: Coronary angiography in the acute and chronic phases revealed no significant stenosis in any TC patient. LV wall motion returned to normal in 17.6 +/- 6.4 days. LVEF was 45.7 +/- 8.8% in the acute phase and 69.8 +/- 6.8% after the improvement of wall motion (p < 0.001). Between 0 months and 3 months, SDNN and SDANN improved significantly, from 88.8 +/- 35.5 to 109.5 +/- 33.4 ms (p = 0.01) and from 79.9 +/- 34.7 to 99.3 +/- 40.3 ms (p = 0.03), respectively. No significant changes were observed in frequency domain parameters. DISCUSSION: These results support our previous hypothesis that TC might be caused by neurogenic stunning of the myocardium, due to acute autonomic dysfunction.

Plasma brain natriuretic peptide in takotsubo cardiomyopathy.

BACKGROUND: Takotsubo cardiomyopathy is a reversible left ventricular dysfunction with symptoms resembling acute myocardial infarction, but without coronary lesions. Patients have wall motion abnormalities (apical akinesis and basal hyperkinesis), and characteristic left ventricular morphology. AIM: To investigate plasma brain natriuretic peptide (BNP) concentrations in takotsubo cardiomyopathy. METHODS: Ten consecutive patients with takotsubo cardiomyopathy underwent cardiac catheterization on their first hospital day, and blood was collected to measure BNP. To evaluate acute basal hyperkinesis, the difference in diameter between systole and diastole was measured at 10 mm below the aortic valve (the deltaBase value). RESULTS: Coronary angiography revealed no significant stenosis in any patient. Initial ejection fraction was 42.2 +/- 7.3%, cardiac index was 1.90 +/- 0.39 l/min/m(2), and plasma BNP was 522.5 +/- 632.9 pg/ml. Ventricular contraction and the ejection fraction were normalized on echocardiography after 17.9 +/- 6.3 days. BNP was significantly correlated with deltaBase, but not with other cardiac parameters. DISCUSSION: Initial deltaBase value seems to be a good indicator of the severity of basal hyperkinesis in patients with takotsubo cardiomyopathy. In contrast to other diagnoses, a high BNP concentration is not associated with a poor prognosis in this condition.

The clinical features of takotsubo cardiomyopathy.

BACKGROUND: Cardiologists have recently recognized a reversible form of heart failure of unknown origin characterized by a takotsubo-shaped hypokinesis of the left ventricle on left ventriculography. AIM: To clarify the clinical features of this cardiomyopathy. DESIGN: Observational study. METHODS: Seven patients with reversible ventricular dysfunction were followed for 4.5 years. Clinical course, routine examinations, and cardiac catheterizations in each patient were documented. RESULTS: The cardiomyopathy developed in six elderly female and one male patients (mean age 75.3 years), all of whom had been exposed to stress. Cardiac enzymes did not significantly increase, but serum norepinephrine increased remarkably (1.19 ng/ml). Coronary angiography revealed normal coronary arteries. However, left ventriculography showed akinesis in the apical segments, together with hyperkinesis in the basal segments (a takotsubo shape). The abnormal kinesis normalized within 17.4 hospital days without any treatment in five patients, and with haemodynamic support for 3 days in the other two. Endocardial biopsies did not suggest any specific pathology. The cardiac events did not recur over a 1-4 year follow-up. DISCUSSION: Coronary vasospasm, myocarditis and other substantial diseases previously described were ruled out as the cause of takotsubo cardiomyopathy in our subjects. Prognosis was good without any form of treatment, provided that the patients survived the severe heart failure state. Catecholaminergic or adrenoceptor-hyperactive cardiomyopathy may be the cause of this cardiomyopathy.

Reversible left ventricular dysfunction "takotsubo" cardiomyopathy associated with pneumothorax.

An 83 year old woman presented to the emergency department with chest pain and dyspnoea. Chest radiography showed pneumothorax of the left lung. Arteries were normal on coronary angiography. Left ventriculography showed asynergy of apical akinesis and basal hyperkinesis. Within 18 days, the asynergy improved without any specific treatment. In the present case the left ventricular dysfunction may have been induced by altered catecholamine dynamics as a result of pneumothorax.