Table 2. Pooled Estimates of Characteristics and Outcomes of Myopericarditis After COVID-19 Vaccination in Adolescents and Young Adults.
| Characteristic | Pooled estimates, % (95% CI) | I2, % | P value for heterogeneity |
|---|---|---|---|
| Age, y | 15.9 (15.5-16.2) | 83.6 | <.001 |
| Sex | |||
| Female | 9.7 (6.8-12.7) | 33.6 | .13 |
| Male | 90.3 (87.3-93.2) | 33.6 | .13 |
| History of COVID-19 | 3.8 (1.1-6.4) | 11.5 | .34 |
| Dose of vaccination | |||
| First | 20.7 (1.0-31.8) | 95.7 | <.001 |
| Second | 74.4 (58.2-90.5) | 97.9 | <.001 |
| Type of vaccine | |||
| BNT162b2 (Pfizer-BioNTech) | 97.5 (95.7-99.2) | 52.8 | .02 |
| mRNA-1273 (Moderna) | 2.2 (0.6-3.7) | 44.7 | .06 |
| Time from vaccination to symptom onset, mean (95% CI), d | 2.6 (1.9-3.3) | 89.0 | <.001 |
| Symptoms | |||
| Chest pain | 83.7 (72.7-94.6) | 98.6 | <.001 |
| Fever | 44.5 (16.9-72.0) | 98.1 | <.001 |
| Headache | 33.3 (8.6-58.0) | 98.0 | <.001 |
| Dyspnea or respiratory distress | 25.2 (17.2-33.1) | 51.2 | .07 |
| Myalgia | 17.8 (2.7-33.3) | 90.9 | <.001 |
| Treatment | |||
| NSAIDs | 81.8 (75.3-88.3) | 45.4 | .09 |
| Glucocorticoid | 13.8 (6.7-20.9) | 67.5 | .005 |
| IVIG | 12.0 (3.8-20.2) | 80.1 | <.001 |
| Colchicine | 7.3 (4.1-10.4) | 0 | .62 |
| Elevated troponin I | 84.5 (75.1-94.5) | 97.5 | <.001 |
| Electrocardiography findings | |||
| ST-segment elevation or changes | 53.0 (34.6-71.3) | 91.5 | <.001 |
| T-wave changes | 14.5 (5.1-24.0) | 0 | .80 |
| Nonsustained VT | 5.3 (2.5-8.1) | 0 | .75 |
| Echocardiography findings | |||
| LVEF, mean (95% CI), % | 62.1 (59.1-65.1) | 71.2 | .03 |
| LV systolic dysfunctiona | |||
| Any | 15.6 (11.7-19.5) | 0 | .90 |
| Mild | 14.1 (10.2-18.1) | 0 | .94 |
| Moderate | 1.3 (0-2.6) | 0 | .98 |
| Severe | 1.3 (0-2.6) | 0 | .96 |
| Pericardial effusion | 5.1 (0.6-9.6) | 45.2 | .11 |
| Cardiac magnetic resonance findings | |||
| Presence of LGE | 87.2 (79.8-94.7) | 52.2 | .08 |
| Myocardial edema | 58.0 (33.5-82.5) | 92.3 | <.001 |
| Outcome | |||
| Hospitalization | 92.6 (87.8-97.3) | 74.0 | <.001 |
| ICU admission | 23.2 (11.7-34.7) | 79.4 | <.001 |
| Inotropes | 1.3 (0-2.7) | 0 | .93 |
| Hospital length of stay, d | 2.8 (2.1-3.5) | 92.9 | <.001 |
Abbreviations: ICU, intensive care unit; IVIG, intravenous immune globulin; LGE, late gadolinium enhancement; LV, left ventricular; LVEF, left ventricle ejection fraction; NSAIDS, nonsteroidal anti-inflammatory drugs; VT, ventricular tachycardia.
a
LV systolic dysfunction was defined as LVEF less than 55%; mild LV systolic function, as LVEF 45% to 54%; moderate, as LVEF 35% to 44%; and severe, as LVEF less than 35%.