Table 4.
Categorical electrocardiographic QRS amplitude changes in COVID-19 by patient disposition
| Voltage characteristic no. (%) | Death (n = 52) | Discharge (n = 88) | p value |
|---|---|---|---|
| Composite low QRS amplitude (LoQRS)* | 25 (48.1) | 9 (10.2) | <0.01 |
| QRS amplitude <5 mm in limb leads AND <10 mm in precordial leads | 0 (0.0) | 0 (0.0) | 0.99 |
| ≥50% decrease in QRS amplitude | 19 (36.5) | 5 (5.7) | <0.01 |
| QRS amplitude <5 mm limb OR <10 mm precordial in precordial leads | 15 (28.9) | 7 (8.0) | 0.001 |
| LoQRS in limb leads | 7 (13.5) | 3 (3.4) | 0.026 |
| LoQRS in precordial leads | 18 (34.6) | 6 (6.8) | <0.01 |
| LoQRS in leads V1-V3 | 10 (19.2) | 5 (5.7) | 0.01 |
| LoQRS in leads V4-V6 | 14 (26.9) | 4 (4.6) | <0.01 |
| LoQRS with LIQRS morphology† | 5 (9.6) | 2 (2.3) | 0.05 |
| Any QRS amplitude increase (baseline to admission ECG) | 8 (15.4) | 8 (9.1) | 0.26 |
| Any QRS amplitude increase (baseline to last ECG) | 4 (7.7) | 11 (12.5) | 0.37 |
| Any QRS amplitude increase (admission to last ECG) | 4 (7.7) | 12 (13.6) | 0.29 |
⁎
Low QRS amplitude (LoQRS) is a composite of relative QRS amplitude reduction by ≥50% from baseline or admission ECG or meeting a threshold of QRS amplitude <5 mm in the limb leads or <10 mm in the precordial leads or in V1-V3 or V4-V6.
†
Limited interpretablity QRS morphology due to change from sinus rhythm, new bundle branch block, or pacing.