The prevalence of ECG manifestations in heat stroke - 'A quick-lit-review'.

The prevalence of ECG manifestations in heat stroke - 'A quick-lit-review'.

Transcript

1. A 'quick-lit-review'. ECG manifestations in heat stroke. B Y S I M O N M A R K D A L E Y ( 2 0 1 9 ) The prevalence of
2. WHY? I reviewed a patient with non-cardiac chest pain, who had presented with heat-stroke. His ECG showed ST-segment deviation, and prompted me to look at the literature for a consensus on the ECG changes likely to manifest in the context of heat stroke.
3. WHAT? Heat stroke is a condition caused by the overheating of the body, usually as a result of prolonged exposure to - or physical exertion in - high temperatures. This can occur if the body's temperature rises to 40c (104f) or higher and is a serious medical issue potentially leading to coma and death. Signs and symptoms include; high temperature, altered mental states, alteration in sweating, nausea and vomiting, flushed skin, tachypnoea, tachycardia & headache.
4. 7 STUDIES IDENTIFIED; "The Heart in Heatstroke". Kew et al (1969). "Electrocardiographic Abnormalities in Patients With Heat Stroke". Akhtar et al (1993). "Heat stroke, an unusual trigger of Brugada electrocardiogram". Lacunza et al (2009). "Stress-Induced Cardiomyopathy Caused by Heat Stroke". Chen et al (2012). (Based on a search for the terms "heat stroke" & "ECG). "Electrocardiographic findings in heat stroke and exhaustion: A study on Makkah pilgrims". Mimish (2012). "Heat Stroke–Induced Sinoatrial Node Dysfunction". Case & Harrington (2015). "Severe heatstroke complicated with Takotsubo cardiomyopathy". Tada et al (2015).
5. KEW ET AL (1969). Evidence of cardiac damage found in 17 of the 26 patients. Myocardial injury was diagnosed by serum lactic dehydrogenase (LDH) isoenzyme alongside their ECG. 69% had raised enzyme, whilst 58% had ECG changes. Most common abnormality was ST-segment deviation, T-wave changes & sinus tachycardia. All of these changes resolved when followed up after cooling treatment completed. 26 Bantu gold-miners suffering heat stroke.
6. AKHTAR ET AL (1993). ECG abnormalities were common; 61% QT interval prolongation. 46% sinus tachycardia. 26% non-specific ST-segment deviation or T-wave changes. 22% conduction defects. 21% ST-segment deviation or T-wave changes corresponding to a specific coronary territory. 46 Hajj pilgrims suffering heatstroke
7. LACUNZA ET AL (2009). Describes a case study in which a young patient (early 30s) presented with heat stroke and reduced Glasgow coma score (GCS) and was found to be Brugada Syndrome (BrS) positive on their ECG. This ECG pattern resolved following cooling treatment and subsequent genetic testing for BrS proved to be negative. Individual case study.
8. CHEN ET AL (2012). Patient with heat stroke presented with ST-segment elevation and cardiogenic shock. Coronary angiogram demonstrated normal coronary arteries . LV-gram was positive, mid-ventricular and apical hypokinesis. Diagnosis was catecholamine-induced Takotsubo cardiomyopathy precipitated by heat stroke. Individual case study.
9. MIMISH ET AL (2012). ECG abnormalities occurred with high frequency in both heat stroke and heat exhaustion groups. Most common abnormality was sinus tachycardia and ischaemic changes, which were most common - by far - in the heat stroke group. Study comparing 3 groups; 34 patients w/ heat stroke. 28 w/ "heat exhaustion". 31 control patients.
10. CASE & HARRINGTON (2015). 87 year old female presented with severe heat stroke and profound bradycardia. ECG showed complete heart block and patient required external pacing. Heart block resolved with aggressive cooling strategies and the patient did not require further management of bradycardia. Individual case study.
11. TADA ET AL (2015). 69 year old female with heat stroke and reduced GCS. ECG showed ST-segment elevation in v2-v6, II, III and avF. Coronary angiogram demonstrated unobstructed coronary arteries. Echocardiogram showed apical ballooning suggestive of Takotsubo cardiomyopathy. Individual case study.
12. Whilst there are no large, multi-center studies, there is a reasonable body of evidence demonstrating that ECG changes are a common manifestation of heat stroke. Most commonly these are; sinus tachycardia, ST- segment deviation and T- wave changes. CONCLUSIONS & CLINICAL IMPLICATIONS; There have been various case studies demonstrating a range of other manifestations including; Takotsubo cardiomyopathy, cardiogenic shock, complete heart block and ST-segment changes suggestive of Brugada syndrome in the absence of corresponding genetic abnormality. ECG manifestations, as well as physical manifestations (such as cardiomyopathy and shock) have been observed to fully resolve with successful cooling therapy. Whilst common, these manifestations should be judged on individual merit & may prompt urgent management to mitigate the potentially life- threatening complications that some of these represent (particularly heart block and cardiogenic shock).
13. Akhtar et al - https://www.sciencedirect.com/science/article/abs/pii/S0012369216353508 Chen et al - https://www.sciencedirect.com/science/article/abs/pii/S0196064411017690 Kew et al - https://www.sciencedirect.com/science/article/abs/pii/0002870369901884 Lacunza et al (2009) - https://www.ajemjournal.com/article/S0735-6757(08)00703-1/abstract Mimish - https://www.sciencedirect.com/science/article/pii/S1016731511002119 Case & Harrington - https://www.sciencedirect.com/science/article/abs/pii/S073646791401453X Tada et al - https://onlinelibrary.wiley.com/doi/full/10.1002/ams2.151 REFERENCES;