Cardiology/case report
Stress-Induced Cardiomyopathy Caused by Heat Stroke

https://doi.org/10.1016/j.annemergmed.2011.11.005Get rights and content

Heat stroke is defined by central nervous system abnormalities and failure of proper maintenance of thermoregulation as a result of high core body temperature ensuing from exposure to high environmental temperatures or strenuous exercise. Common complications include acute respiratory distress syndrome, disseminated intravascular coagulation, acute renal injury, hepatic injury, and rhabdomyolysis. Myocardial injury may also occur during heat stroke, resulting in cardiac enzyme increase and ST-segment changes on the ECG. Such findings might behave as diagnostic pitfalls by mimicking the presentation of coronary artery occlusive myocardial infarction. A previous case report described a patient with heat stroke and ST-segment elevation, in which the definite cause of the ST-segment elevation was unclear; however, acute myocardial infarction caused by coronary artery disease was ruled out according to the clinical signs, serial ECG changes, and serum level of cardiac biomarkers. Stress-induced cardiomyopathy (Takotsubo cardiomyopathy) was suspected, but it could not be confirmed because of the lack of coronary angiography. We herein report a case of heat stroke presenting with ST-segment elevation and cardiogenic shock. Coronary angiography was performed and coronary artery occlusive myocardial infarction was ruled out because of the presence of patent coronary arteries. Left ventriculography showed midventricular and apical hypokinesis, and stress-induced cardiomyopathy was then determined to be the appropriate diagnosis. Heat stroke causes increase of serum catecholamine levels, in which oversecretion and abnormal responses to catecholamines are a possible cause of stress-induced cardiomyopathy. Catecholamines may therefore be the key in linking heat stroke and stress-induced cardiomyopathy.

Introduction

Heat stroke is defined clinically by core body temperature exceeding 40°C (104°F), failure of thermoregulation, and central nervous system abnormalities such as delirium, convulsions, or coma. Heat stroke occurs during exposure to high environmental temperatures or during the performance of strenuous work and is classified as classic or exertional.1 Cooling, airway protection, supportive care, and management for complications are the mainstays of treatment. Mortality correlates with age and the degree of temperature increase, which affects the organs and the effectiveness of treatment.2

Heat stroke may cause multiorgan dysfunction syndromes. The myocardial injury of the heat stroke often presents with elevation of cardiac enzymes and electrocardiographic changes, which might act as diagnostic pitfalls.3, 4, 5 Such findings may lead to an erroneous diagnosis of acute myocardial infarction caused by coronary atherosclerosis subsequently followed by improper treatment. Wakino et al6 and Garcia-Rubira et al7 have described heat stroke patients with electrocardiographic ST-segment elevation diagnosed as acute myocardial infarction, in which transient coronary artery spasms or stress-induced cardiomyopathy was suspected; however, coronary angiography is necessary to make such diagnoses, yet these data were lacking in those studies. In addition, acute myocardial infarction from coronary artery occlusion should be ruled out before the diagnosis of coronary artery spasms or stress-induced cardiomyopathy is made. Coronary angiography was not performed in these cases, and acute coronary artery occlusive myocardial infarction was ruled out by indirect methods, including echocardiographic findings, the evolutional changes of ECG, the symptoms, and the physical signs.

We herein present another case of high core body temperature with hypotension and pulmonary edema. In addition, the laboratory data presented increased cardiac troponin I and ST-segment elevation at V4 to 6 by ECG. Echocardiogram revealed left ventricle systolic dysfunction with regional wall motion abnormality. Coronary angiography and left ventriculography were also performed, revealing patent coronary arteries, hence suggesting stress-induced cardiomyopathy. To the best of our knowledge, no previous studies have reported a direct method for ruling out myocardial infarction from coronary artery occlusion in patients with heat stroke and ST-segment elevation or provided direct evidence of stress-induced cardiomyopathy. Therefore, this is the first case report of coronary angiography displaying stress-induced cardiomyopathy in a patient with heat stroke.

Section snippets

Case Report

A 39-year-old male construction worker worked in an open field, with an ambient temperature of 35.6°C (96°F). After working for approximately 8 hours, he suddenly collapsed and was immediately sent to our emergency department. He presented with an infrared tympanic temperature on admission of 42.2°C (108°F) and rectal temperature was 43.1°C (109.6°F) and was determined to be 6 points on the Glasgow Coma Scale. Blood pressure was 98/50 mm Hg, pulse rate 160 beats/min, and respiratory rate 30

Discussion

ST-segment elevation is one of the ECG findings in patients with heat stroke.3, 4, 5, 6, 7 In addition, previous reports have indicated that patients with heat stroke and ST-segment elevation do not have symptoms of angina pectoris.6 Although echocardiography during the acute phase revealed segmental hypokinesis of the left ventricle, this condition resolved spontaneously in the absence of any specific treatment for acute coronary syndrome. In addition, ECG did not reveal Q waves in the

References (15)

There are more references available in the full text version of this article.

Cited by (34)

  • Sudden death during physical restraint by the Dutch police

    2020, Journal of Forensic and Legal Medicine
    Citation Excerpt :

    Hyperthermia leads to loss of consciousness, epilepsy, break down of muscles and renal failure. Hyperthermia can cause acute heart failure or stress cardiomyopathy,43 acute myocardial infarction, and incessant ventricular arrhythmias.44 During stress, cortisol levels elevate and as a result of this adrenaline and noradrenaline rise (fight or flight response).

  • Association between heat stroke and ischemic heart disease: A national longitudinal cohort study in Taiwan

    2019, European Journal of Internal Medicine
    Citation Excerpt :

    In a retrospective cohort study, Yang et al. analyzes the data from 117 consecutive patients (86 survivors, 31 nonsurvivors) who has suffered an exertional heat stroke, at 48 Chinese hospitals between April 2003 and July 2015, which demonstrates that recurrent heat strokes could predispose to central nervous system injuries [6]. Heat stroke can cause multiple syndromes including bowel ischemia, [7] acute liver failure, [8] coagulopathy, [9] impaired renal function with electrolyte disturbances [10] and myocardial damage [11,12]. It is reported that patients who have suffered a heat stroke might have decreased left-ventricular end-diastolic volume, leading to a reduced cardiac stroke volume and decrease in coronary artery perfusion [13], resulting in ischemic heart disease (IHD).

View all citing articles on Scopus

Supervising editor: Deborah B. Diercks, MD

Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article as per ICMJE conflict of interest guidelines (see www.icmje.org). The authors have stated that no such relationships exist.

Publication date: Available online December 7, 2011.

View full text