Transient left ventricular apical ballooning developing after the Central Niigata Prefecture Earthquake: two case reports.

Two patients presented with transient left ventricular apical ballooning (takotsubo cardiomyopathy) induced by emotional stress caused by the Central Niigata Prefecture Earthquake in 2004. These patients complained of chest pain immediately after the earthquake. In patient 1, electrocardiography (ECG) showed slight ST elevation in leads V5 to V6 and 1 mm ST depression in lead III. Serial ECG revealed inverted giant T waves in leads V3 to V6 and inverted T waves in leads I, II, aVL and aVF 13 days after the earthquake occurred. Patient 2 also complained of chest pain right after the earthquake, but consulted a doctor 15 days after the earthquake occurred. ECG showed inverted giant T wave in leads V1 to V6 and inverted T waves in leads I, II and aVL. Transthoracic echocardiography showed hypokinesis of the apical area of the left ventricle with normokinesis in the basal area in both patients. Coronary angiography showed no stenotic segments and coronary spasms were not induced by provocative testing. Serial cardiac radionuclide single photon emission computed tomography of myocardial functional sympathetic innervation using iodine-123-metaiodobenzyl-guanidine (MIBG) and thiallium-201 (201Tl) showed an MIBG uptake defect and increased wash-out in the apical area, but only mild decrease of apical 201Tl uptake. Due to strong emotional stress, earthquakes may induce transient left ventricular apical ballooning (takotsubo cardiomyopathy).