Study characteristics
The systematic search resulted in 853 records, and after eliminating duplicates, 557 articles remained. Then, after screening titles and abstracts of the remaining articles, 181 studies were selected to be potentially eligible. Afterwards, based on the mentioned exclusion and inclusion criteria, 40 articles were included in the present systematic review and meta-analysis (Fig. 1) (5, 8–46). These 40 articles were treated as 60 different experiments, as some studies reported more than one cardiac complication/abnormality. Two studies were taken place in the United States (41, 45), one study was conducted in Spain (9), one study was in Italy (42) and the rest of the included studies were conducted in China. Regarding the study design of the included articles, one study was ambispective (22), four studies were conducted prospectively (9, 14, 19, 39) and the other 35 studies were retrospective. Overall, 15616 patients confirmed with COVID-19 were enrolled in the included studies, with 2985 males among them [patients’ gender was not reported in two of the studies (42, 46)]; however, not all of the patients were assessed for each cardiac complication, so the total number of patients tested for each manifestation is presented for each complication in Table 1. In general, 9 different cardiac complications/abnormalities were reported in the studies including acute cardiac injury, which was reported in 26 studies (5, 8, 11, 13, 16, 18–20, 22–24, 26–30, 32, 33, 35, 37–41, 43, 46), abnormal serum troponin level, reported in 19 studies (8, 10–12, 14, 15, 17, 19, 25, 30, 32, 36–38, 40, 41, 43–45), heart failure, reported in four studies (8, 11, 32, 41), cardiac arrest, reported in three studies (5, 34, 42), myocarditis, reported in two studies (9, 44), cardiac insufficiency, reported in two studies (29, 30), pericardial effusion, reported in two studies (21, 31) and cardiomyopathy (45) and myocardial infarction (32), each reported in one study. Mortality rate was reported in 18 studies (8, 11, 13, 14, 16–18, 20, 26, 29, 30, 33, 34, 37, 39, 40, 44, 46). These numbers were further used to evaluate the odds ratio (OR) between the appearance of each cardiac complication and the mortality rate in COVID-19 patients. Table 1 demonstrates a summary of the characteristics of the included studies.
Table 1
Summary of the included studies
Author; Year; Country | Study design | Total study population | Mean age | Number of males | Diagnostic methods | Type of cardiac complication | No. of patients tested for the complication | No. of the complication | No. of deceased in patients with the complication | No. of deceased in patients without the complication |
Aggarwal S; 2020; USA | Retrospective | 16 | 67 | 12 | Blood Sample, Echo | Acute cardiac injury | 16 | 3 | NR | NR |
| | | | | NR | Heart failure | 16 | 2 | NR | NR |
| | | | | Blood Sample | Abnormal Troponin | 16 | 10 | NR | NR |
Arentz M; 2020; USA | Retrospective | 21 | 70 | 11 | Blood Sample, Echo, Clinical | Cardiomyopathy | 21 | 7 | NR | NR |
| | | | | Blood Sample | Abnormal Troponin | 21 | 3 | NR | NR |
Baldi E; 2020; Italy | Retrospective | 9806 | NR | NR | Hospital report | Cardiac arrest | 9806 | 362 | NR | NR |
Barrasa H; 2020; Spain | Prospective | 48 | 63.2 | 27 | NR | Myocarditis | 48 | 1 | NR | NR |
Chen C; 2020; China | Retrospective | 150 | 59 | 84 | Blood Sample | Abnormal Troponin | 150 | 22 | NR | NR |
Chen T; 2020; China | Retrospective | 274 | 62 | 171 | NR | Acute cardiac injury | 203 | 89 | 72 | 22 |
| | | | | NR | Heart failure | 176 | 43 | 41 | 42 |
| | | | | Blood Sample | Abnormal Troponin | 203 | 83 | 68 | 26 |
Deng Q; 2020; China | Retrospective | 112 | 65 | 57 | Blood Sample | Abnormal Troponin | 112 | 42 | NR | NR |
Deng Y; 2020; China | Retrospective | 225 | 54 | 124 | Blood Sample | Acute cardiac injury | 225 | 66 | 65 | 44 |
Du Ra; 2020; China | Prospective | 179 | 57.6 | 97 | Blood Sample | Abnormal Troponin | 179 | 31 | 13 | 8 |
Du Rb; 2020; China | Retrospective | 109 | 70.7 | 75 | Blood Sample | Abnormal Troponin | 109 | 52 | NR | NR |
Du Y; 2020; China | Retrospective | 85 | 65.8 | 62 | Blood Sample | Acute cardiac injury | 85 | 38 | NR | NR |
| | | | | Clinical | Cardiac arrest | 85 | 7 | NR | NR |
Guo T; 2020; China | Retrospective | 187 | 58.5 | 91 | Blood Sample | Acute cardiac injury | 187 | 52 | 31 | 12 |
Han H; 2020; China | Retrospective | 273 | NR | 97 | Blood Sample | Abnormal Troponin | 273 | 27 | 13 | 8 |
He X; 2020; China | Retrospective | 54 | 68 | 34 | Blood Sample | Acute cardiac injury | 54 | 24 | 18 | 8 |
Hu L; 2020; China | Retrospective | 323 | 61 | 166 | Blood Sample | Acute cardiac injury | 323 | 24 | NR | NR |
| | | | | Blood Sample | Abnormal Troponin | 323 | 68 | NR | NR |
Huang C; 2020; China | Prospective | 41 | 49 | 30 | Blood Sample | Abnormal Troponin | 41 | 5 | NR | NR |
| | | | | | Acute cardiac injury | 41 | 5 | NR | NR |
Lei S; 2020; China | Retrospective | 34 | 55 | 14 | Blood Sample | Acute cardiac injury | 34 | 5 | 4 | 3 |
Li K; 2020; China | Retrospective | 83 | 45.5 | 44 | CT | Pericardial effusion | 83 | 4 | NR | NR |
Li X; 2020; China | Ambispective | 548 | 60 | 279 | Blood Sample | Acute cardiac injury | 548 | 119 | NR | NR |
Li Y; 2020; China | Retrospective | 54 | 61.8 | 34 | Blood Sample | Acute cardiac injury | 41 | 23 | NR | NR |
Liu M; 2020; China | Retrospective | 30 | 35 | 10 | Blood Sample | Acute cardiac injury | 30 | 5 | NR | NR |
Liu Y; 2020; China | Retrospective | 76 | 45 | 49 | Blood Sample | Abnormal Troponin | 76 | 14 | NR | NR |
Ma K; 2020; China | Retrospective | 84 | 48 | 48 | Blood Sample | Abnormal Troponin | 84 | 36 | 0 | 0 |
| | | | | Blood Sample, Clinical Symptom | Myocarditis | 84 | 4 | 0 | 0 |
Ruan Q; 2020; China | Retrospective | 150 | NR | NR | NR | Acute cardiac injury | 68 | 5 | 5 | 63 |
Shi S; 2020; China | Retrospective | 416 | 64 | 205 | Blood Sample | Acute cardiac injury | 416 | 82 | 42 | 15 |
Wan S; 2020; China | Retrospective | 135 | 47 | 72 | Blood Sample | Acute cardiac injury | 135 | 10 | NR | NR |
Wang Da; 2020; China | Retrospective | 138 | 56 | 75 | Blood Sample, ECG, Echo | Acute cardiac injury | 138 | 10 | NR | NR |
Wang Db; 2020; China | Retrospective | 107 | 51 | 57 | Blood Sample | Abnormal Troponin | 107 | 6 | 5 | 14 |
| | | | | Blood Sample, ECG, Echo | Acute cardiac injury | | 12 | 8 | 19 |
Wang La; 2020; China | Retrospective | 339 | 69 | 166 | Blood Sample | Acute cardiac injury | 339 | 70 | 39 | 26 |
| | | | | Blood Sample, Clinical Symptom | Cardiac insufficiency | 339 | 58 | 25 | 52 |
Wang Lb; 2020; China | Retrospective | 202 | 63 | 88 | Blood Sample | Acute cardiac injury | 202 | 27 | 17 | 14 |
| | | | | Blood Sample, ECG, Echo | Cardiac insufficiency | 202 | 24 | 14 | 19 |
| | | | | Blood Sample | Abnormal Troponin | 202 | 27 | NR | NR |
Wei J; 2020; China | Prospective | 101 | 49 | 54 | Blood Sample | Acute cardiac injury | 101 | 16 | 3 | 0 |
Xu X; 2020; China | Retrospective | 90 | 50 | 39 | CT | Pericardial effusion | 90 | 1 | NR | NR |
Yang F; 2020; China | Retrospective | 92 | 69.8 | 49 | Blood Sample | Acute cardiac injury | 92 | 31 | NR | NR |
| | | | | NR | Myocardial infarction | 92 | 6 | NR | NR |
| | | | | NR | Heart failure | 92 | 2 | NR | NR |
| | | | | Blood Sample | Abnormal Troponin | 92 | 31 | NR | NR |
Yang X; 2020; China | Retrospective | 52 | 59.7 | 35 | Blood Sample | Acute cardiac injury | 52 | 12 | 9 | 23 |
Yao W; 2020; China | Retrospective | 202 | 63.4 | 136 | Clinical | Cardiac arrest | 202 | 4 | 0 | 21 |
Zhang G; 2020; China | Retrospective | 221 | 55 | 108 | NR | Acute cardiac injury | 221 | 17 | NR | NR |
Zhao X; 2020; China | Retrospective | 91 | 46 | 49 | Blood Sample | Acute cardiac injury | 91 | 14 | NR | NR |
| | | | | Blood Sample | Abnormal Troponin | 88 | 3 | NR | NR |
Zheng Y; 2020; China | Retrospective | 99 | 49.4 | 51 | Blood Sample | Abnormal Troponin | 99 | 88 | NR | NR |
Zhou F; 2020; China | Retrospective | 191 | 56 | 119 | Blood Sample | Abnormal Troponin | 145 | 24 | 23 | 31 |
| | | | | | Heart failure | 145 | 44 | 28 | 26 |
| | | | | | Acute cardiac injury | 145 | 33 | 32 | 22 |
Zou X; 2020; China | Retrospective | 178 | 60.68 | 67 | Blood Sample, ECG, Echo | Acute cardiac injury | 154 | 45 | 34 | 18 |
| | | | | Blood Sample | Abnormal Troponin | 154 | 33 | 28 | 24 |
CT: Computed tomography scan; Echo: Echocardiography; ECG: Electrocardiography; NR: Not reported |
Meta-analysis
In the beginning, the prevalence of cardiac complications following SARS-CoV-2 infection was evaluated, and the results are depicted in Figs. 3, 4, 5 and 6 and Table 3. The abnormal serum level of troponin was observed in 22.86% (95% CI: 21.19 to 24.56) of the patients (Fig. 4). Moreover, the prevalence of acute cardiac injury, heart failure and cardiac arrest were 19.46% (95% CI: 18.23 to 20.72), 19.07% (95% CI: 15.38 to 23.04) and 3.44% (95% CI: 3.08 to 3.82), respectively (Fig. 3 and Table 3). Furthermore, the I2 test revealed no heterogeneity regarding the prevalence of abnormal troponin levels and acute cardiac injury. The prevalence of other cardiac complications including myocarditis, cardiac insufficiency, pericardial effusion, myocardial infarction and cardiomyopathy are depicted in Table 3.
Table 3
Summary of finding regarding the cardiac complications in COVID-19
Complication | Number of studies | Prevalence | 95% CI | | Number of studies | Odds ratio | 95% CI | P |
Acute cardiac injury | 26 | 19.46 | 18.23, 20.72 | | 14 | 14.24 | 8.67, 23.38 | < 0.001 |
Abnormal troponin | 19 | 22.86 | 21.19, 24.56 | | 6 | 19.03 | 11.85, 30.56 | < 0.001 |
Heart failure | 4 | 19.07 | 15.38, 23.04 | | 2 | 10.66 | 5.69, 19.97 | < 0.001 |
Cardiac arrest | 3 | 3.44 | 3.08, 3.82 | | 1 | 0.04 | 0.00, > 999.0 | 0.651 |
Myocarditis | 2 | 3.66 | 0.88, 7.82 | | 1 | 1.00 | 0.00, > 999.0 | > 0.99 |
Pericardial effusion | 2 | 2.62 | 0.58, 5.73 | | --- | --- | --- | --- |
Cardiac insufficiency | 2 | 15.06 | 12.15, 18.22 | | 2 | 4.65 | 2.82, 7.66 | < 0.001 |
Cardiomyopathy | 1 | 33.33 | 17.19, 54.63 | | --- | --- | --- | --- |
Myocardial infarction | 1 | 6.52 | 3.02, 13.51 | | --- | --- | --- | --- |
---: No data; CI: Confidence interval |
Further analysis revealed that the odds of mortality in COVID-19 patients with acute cardiac injury is 14.24 (OR = 14.24, 95% CI: 8.67 to 23.38) times higher than the COVID-19 patients without acute cardiac injury. However, I2 test showed some degrees of heterogeneity regarding the relationship of cardiac complication and mortality of COVID-19 patients (Fig. 5). Moreover, the odds of mortality in a COVID-19 patient presenting with abnormal serum troponin level in his/her blood sample was 19.03 (OR = 19.03; 95% CI: 11.85 to 30.56) times higher than the patients not having this manifestation. Interestingly, no heterogeneity was observed when calculating the OR for the mortality in COVID-19 patients with abnormal serum troponin level (Fig. 6). The odds of mortality of patients having other cardiac complications are presented in Table 3.