Electrocardiographic manifestations of COVID-19: Effect on cardiac activation and repolarization.

BACKGROUND

Prolonged QT intervals are reported in patients with COVID-19. Additionally, virus particles in heart tissue and abnormal troponin levels have been reported. Consequently, we hypothesize that cardiac electrophysiologic abnormalities may be associated with COVID-19.

METHODS

This is a retrospective study between March 15, 2020 and May 30, 2020 of 828 patients with COVID-19 and baseline ECG. Corrected QT (QTc) and QRS intervals were measured from ECGs performed prior to intervention or administration of QT prolonging drugs. QTc and QRS intervals were evaluated as a function of disease severity (patients admitted versus discharged; inpatients admitted to medical unit vs ICU) and cardiac involvement (troponin elevation >0.03 ng/ml, elevated B-natriuretic peptide (BNP) or NT pro-BNP >500 pg/ml). Multivariable analysis was used to test for significance. Odds ratios for predictors of disease severity and mortality were generated.

FINDINGS

Baseline QTc of inpatients was prolonged compared to patients discharged (450.1±30.2 versus 423.4±21.7  msec, <0.0001) and relative to a control group of patients with influenza (=0.006). Inpatients with abnormal cardiac biomarkers had prolonged QTc and QRS compared to those with normal levels (troponin - QTc: 460.9±34.6 versus 445.3±26.6  msec, <0.0001, QRS: 98.7±24.6 vs 90.5±16.9  msec, <0.0001; BNP - QTc: 465.9±33.0 versus 446.0±26.2  msec, <0.0001, QRS: 103.6±25.3 versus 90.6±17.6 msec, <0.0001). Findings were confirmed with multivariable analysis (all <0.05). QTc prolongation independently predicted mortality (8.3% increase in mortality for every 10  msec increase in QTc; OR 1.083, CI [1.002, 1.171], =0.04).

INTERPRETATION

QRS and QTc intervals are early markers for COVID-19 disease progression and mortality. ECG, a readily accessible tool, identifies cardiac involvement and may be used to predict disease course.

FUNDING

St. Francis Foundation.