Electrocardiographic findings and mortality in covid-19 patients hospitalized in different clinical settings.

Background: Twelve-lead electrocardiogram (ECG) represents the first-line approach for cardiovascular assessment in patients with Covid-19.

Objectives: We sought to describe and compare admission ECG findings in 3 different hospital settings: intensive-care unit (ICU) (invasive ventilatory support), respiratory care unit (RCU) (non-invasive ventilatory support) and Covid-19 dedicated internal-medicine unit (IMU) (oxygen supplement with or without high flow). We also aimed to assess the prognostic impact of admission ECG variables in Covid-19 patients.

Methods: We retrospectively analyzed the admission 12-lead ECGs of 1124 consecutive patients hospitalized for respiratory distress and Covid-19 in a single III-level hospital. Age, gender, main clinical data and in-hospital survival were recorded.

Results: 548 patients were hospitalized in IMU, 361 in RCU, 215 in ICU. Arrhythmias in general were less frequently found in RCU (16% vs 26%, p<0.001). Deaths occurred more frequently in ICU patients (43% vs 20-21%, p<0.001). After pooling predictors of mortality (age, intensity of care setting, heart rate, ST-elevation, QTc prolongation, Q-waves, right bundle branch block, and atrial fibrillation), the risk of in-hospital death can be estimated by using a derived score. Three zones of mortality risk can be identified: <5%, score <5 points; 5-50%, score 5-10, and >50%, score >10 points. The accuracy of the score assessed at ROC curve analysis was 0.791.

Conclusions: ECG differences at admission can be found in Covid-19 patients according to different clinical settings and intensity of care. A simplified score derived from few clinical and ECG variables may be helpful in stratifying the risk of in-hospital mortality.