Role of Telemetry Monitoring to Detect the Onset of Tako‐tsubo Cardiomyopathy in Consciousness Disturbance

To the Editor: Tako-tsubo cardiomyopathy is characterized by transient left ventricular apical wall motion abnormality with electrocardiographic changes and minimal myocardial enzymatic release, mimicking acute myocardial infarction.1-3 Most patients with tako-tsubo cardiomyopathy are elderly women, who experience chest pain or discomfort during the early phase. Subjective symptoms are often useful in making an early and precise diagnosis, but tako-tsubo cardiomyopathy may occur in patients who are in a coma and are unable to complain about their symptoms. We report a case of brain infarction in which telemetry monitoring was found to be useful for detecting the onset of tako-tsubo cardiomyopathy. An 83-year-old hypertensive woman was admitted to Hiroshima City Hospital with right hemiparesis and consciousness disturbance. On physical examination, she was unconscious with a Glasgow Coma Scale score of 7/15. Her temperature was 36.6°C, pulse rate 80 beats per minute, blood pressure 180/90 mmHg, and oxygen saturation 98% on room air. Auscultation revealed no cardiac murmurs or rales. Electrocardiogram showed shallow negative T-wave inversion in leads V5-6, and chest X-ray showed no pulmonary edema. Subsequent magnetic resonance imaging showed a lesion responsible for these symptoms, and she was diagnosed with a brain infarction. Continuous telemetry monitoring was started immediately after admission (Figure 1A). Telemetry monitoring showed a flat T-wave for longer than 12 hours. A manifest T-wave inversion appeared 20 hours later, but ST-segment elevation was not seen during follow-up. She could not complain about her symptoms because she was in a coma, but she had no objective findings suggestive of congestive heart failure, such as tachypnea, tachycardia, or decreased oxygen saturation. Transthoracic echocardiography showed apical akinesia and basal hyperkinesia of the left ventricle (Figure 1B, C). She was diagnosed with tako-tsubo cardiomyopathy after brain infarction. Paroxysmal atrial fibrillation occurred 2 days later, but no major cardiac event occurred. T-wave inversion persisted during follow-up, but left ventricular function returned to normal 7 days later. Telemetry monitoring showed a flat T-wave for longer than 12 hours. A manifest T-wave inversion appeared 20 hours later, but ST-segment elevation was not seen during follow-up (A). Transthoracic echocardiography showed apical akinesia and basal hyperkinesia of the left ventricle (B, C). This report demonstrates that T-wave inversion on telemetry monitoring might be useful for detecting the onset of tako-tsubo cardiomyopathy in patients in a coma. Since tako-tsubo cardiomyopathy was first reported in 1990,1 this disorder has been recognized worldwide. Most patients have been elderly women, symptoms are similar to those of acute myocardial infarction, and patients have often experienced emotional or physical stress before onset. Tako-tsubo cardiomyopathy should be considered in the differential diagnoses of acute myocardial infarction. In our case, acute stress due to brain infarction could have been a precipitating factor leading to tako-tsubo cardiomyopathy. Because apical ballooning of tako-tsubo cardiomyopathy is transient and resolves dramatically in a short time, its prognosis is generally favorable, although recent reports have demonstrated early life-threatening complications, including left ventricular rupture,4, 5 arrhythmia,6 heart failure, cardiogenic shock, and apical thrombus formation.7 Early diagnosis and subsequent treatment are required to prevent these complications even in patients with tako-tsubo cardiomyopathy. Tako-tsubo cardiomyopathy often occurs as a complication of noncardiac disorders. The development of tako-tsubo cardiomyopathy may be diagnosed at a later stage or overlooked, especially in patients who are in a coma. Clinicians should recognize that there is a possibility of the development of tako-tsubo cardiomyopathy when T-wave inversion appears in patients with noncardiac disorders during hospitalization. Transthoracic echocardiography or repeated electrocardiogram should be performed routinely in these patients.