Nuclear medicine imaging of takotsubo cardiomyopathy: Typical form and midventricular ballooning syndrome

Abstract

Transient left ventricular (LV) apical ballooning syndrome, also known as takotsubo cardiomyopathy (TTC), was first described in the early 1990s in Japan. 1 TTC symptoms and electrocardiographic findings are close to those of acute myocardial infarction. 2 Cardiac enzyme levels, such as creatinine phosphokinase and troponin I, are slightly increased. During the acute phase, 2-dimensional transthoracic echocardiography (TTE) demonstrates akinesia or dyskinesia of the apical and midventricular segments associated with hypercontractility of the LV base. Emergency left ventriculography confirms TTE motion abnormalities and reveals a typical apical ballooning aspect at end systole. Coronary angiography reveals an absence of significant organic stenosis in the epicardial coronary arteries. 3,4 Variant forms of TTC, known as "inverted takotsubo" or "midventricular ballooning syndrome," have been described recently. 5-7 TTC is often triggered by preceding physical or emotional stress, but its pathophysiologic bases remain poorly understood. 4,[8][9][10][11] We describe 2 didactic cases of TTC: the first with typical apical ballooning of the left ventricle and second with an uncommon LV midportion dilatation. In both patients LV perfusion, glucose metabolism, and sympathetic innervation were assessed by nuclear medicine techniques.Patient 1: Transient ventricular apical ballooning. An 83-year-old white woman who had no cardiovascular history and was treated for mild hyperlipidemia was referred to our institution for further examination of ischemic-like chest pain. At admission, the systolic blood pressure was normal, and the heart rate was 85 beats/min with a regular rhythm. Respiratory crackles were heard bilaterally. Electrocardiography revealed STsegment elevation in the following leads: D1, aVL, and V 1 through V 6 . Biologic results showed a maximum troponin I level of 4.56 ng/mL (normal value Ͻ0.14 ng/mL) and total creatine kinase level of 390 IU/L (normal value Ͻ200 IU/L). TTE revealed LV apical akinesis, discrete dyskinesis of the septal mid-ventricle, and preserved basal function. The left ventricular ejection fraction (LVEF) was moderately decreased (40%). Coronary angiography showed normal epicardial coronary arteries. Left ventriculography confirmed wall motion abnormalities in the apical and mid-septal areas with hypercontractility of basal segments. TTE revealed improvement of LV wall motion and function (LVEF of 55%) within 1 month.Patient 2: Transient midventricular ballooning. A 67-year-old white woman with no prior history of cardiovascular disease and no coronary risk factors presented to our emergency department because of chest pain. Clinical examination and routine biologic evaluation showed no remarkable findings, except moderately increased troponin I and total creatine kinase levels: 4.15 ng/mL and 258 IU/L, respectively. Electrocardiographic recording was normal. At admission, TTE showed akinesis of LV mid-segments and hypercontractility of both apex and base. LVEF was moderately decreased (42%)....

Scintigraphic Evaluation of Takotsubo Cardiomyopathy

“…In keeping with other published studies however, myocardial perfusion was not completely absent even on the stress study [6]. In fact, some reports have noted that myocardial perfusion may be completely normal despite significant wall motion abnor- malities and the presence of symptoms [7,8]. Although the perfusion abnormality in the apex can be partially explained by a partial volume effect involving the non-thickening apical segments [9,10], many studies have demonstrated that microvascular dysfunction may be responsible for a true perfusion defect [6,11,12].…”

“…Reduction in fatty acid metabolism occurs under conditions of ischemia and has been documented through SPECT imaging with I-123 BMIPP [6, 12]. On PET imaging, reduced perfusion with N-13 ammonia [13] and decreased metabolism with F-18 FDG imaging has also been described [7,13]. The radio-iodinated analog for norepinephrine I-123 MIBG has also been used to demonstrate a suppression of myocardial sympathetic nerve function in response to myocardial ischemia in TC.…”

Stress-Induced Cardiomyopathy: Assessment with Cardiac Magnetic Resonance Imaging and Multi-Detector Computed Tomography

“…In the acute and subacute phases of stress-induced cardiomyopathy, the affected hypocontractile ventricular segment shows defects of MIBG and FDG uptake despite normal to slightly reduced perfusion. Subsequent rapid normalization of myocardial perfusion and delayed recovery of both LV glucose metabolism and sympathetic innervation are also observed [25,26].…”

“…Single-photon emission computed tomography can assess neurogenic myocardial stunning, a consequence of defects in myocardial perfusion and sympathetic innervation, using 201 Thallium or 99m Technetium-labelled radiopharmaceuticals and 123 I-metalodobenzylguanidine (I-123 MIBG). Likewise, 18F-fluorodeoxyglucose (FDG) positron emission tomography can be used to detect myocardial glucose metabolism [25,26]. In the acute and subacute phases of stress-induced cardiomyopathy, the affected hypocontractile ventricular segment shows defects of MIBG and FDG uptake despite normal to slightly reduced perfusion.…”

A Comprehensive Literature Review of the Epidemiology, Diagnosis and Management of Takotsubo Cardiomyopathy Syndrome

“…The mid-ventricular type: accounts for ~40% [10] is characterized by transient LV midsegment akinesis but preservation of LV apical segment [17]. The localized type: is characterized by any other segmental LV dysfunction with clinical characteristics similar to takotsubo-like LV dysfunction.…”