Validation of Corrected and Dispersed QT as Predictors of Adverse Outcomes in Acute Cardiotoxicities.

Abstract

Acute cardiovascular poisoning is a major cause of adverse outcomes in poisoning emergencies. The prognostic validity of corrected QT (QTc) and dispersed QT (QTd) in these outcomes is still limited. The present study aimed to determine the risk factors of mortality, adverse cardiovascular events (ACVE), and intensive care unit (ICU) admission in patients with acute cardiovascular toxicities and assess the validity of QTc and QTd intervals in predicting these outcomes. This study was conducted on adult patients admitted to Tanta University Poison Control Center with a history of acute cardiotoxic drugs or toxins exposure. The demographic and toxicological data of patients were recorded. Clinical examination, routine laboratory investigations, ECG grading, and measurement of QTc and QTd were performed. The patients were grouped according to their adverse outcomes. Among the included patients, 51 (31.48%) patients died, 61 (37.65%) patients had ACVE, and 68 (41.98%) patients required ICU admission. The most common cause of poisoning is aluminum phosphide, followed by cholinesterase inhibitors. QTd and QTdc showed no significant difference among outcome groups. The best cut-off values of QTc to predict mortality, ACVE, and ICU admission were > 491.1ms, > 497.9ms, and ≥ 491.9ms, respectively. The derived cut-off QTc values were independent predictors for all adverse outcomes after adjusting for poison type, serum HCO3, and pulse. The highest odds ratios for all adverse outcomes were observed in aluminum phosphide poisoning and low HCO3 < 18mmol/L. Thus, serum HCO3 and QTc interval should be monitored for acute cardiotoxicities, especially in aluminum phosphide and cholinesterase inhibitors poisoning.