Changes in Subclinical Cardiac Abnormalities 1 Year after Recovering from COVID-19 in Patients without Clinical Cardiac Findings

Background: The follow-up of cardiovascular sequelae of participants recovered from coronavirus disease 2019 (COVID-19) without cardiac symptoms or clinical findings is not well known. This study to evaluate changes of subclinical cardiac involvement in longitudinal follow-up in participants recovered from COVID-19 without clinical evidence of cardiac involvement using cardiac MRI.Methods: In this longitudinal prospective observational cohort study, participants recovered from COVID-19 and no cardiovascular medical history, without cardiac symptoms, with normal ECG, normal serological cardiac enzyme levels, and discharged > 180 days at baseline CMR had follow up after discharged > 300 days. Demographic characteristics, serum cardiac enzymes, and cardiac MRI were obtained. Cardiac function, native T1, ECV and Two-dimensional (2D) strain were quantitatively evaluated and compared with controls (n = 20).Findings: Twenty participants (mean age±standard deviation, 50±11 years; 10 men) enrolled with baseline cardiac MRI examination had mean durations from admission and discharge of 156 ±15 days and 126 ±17 days, respectively. The Follow-up mean durations from admission and discharge to cardiac MRI examination were 394±57 days and 364±58 days, respectively. There was no LV and RV size or functional differences among participants recovered from COVID-19 at baseline and follow-up as compared to healthy controls. All baseline and follow-up studies were negative for LGE. Global ECV values was elevated in both baseline and follow-up groups, compared with the healthy controls (median ECV (IQR) COVID-19 baseline, 30.0% (28.3%-32.5%), follow-up, 31.0% (28.0%-32.8%), healthy control group, 27.0% (25.3%-28.0%); p<.001 for both baseline and follow-up groups compared to control). The mean global native T1 (median (IQR) COVID-19 baseline,1140(1108.3-1192.0) ms, follow-up, 1176.0(1113.0-1206.3) ms, healthy control group, 1160.7(1119.6-1195.4) ms; p=.224) were not different among these groups. The mean global T2 at follow-up were 41(40-42) ms which was within the normal range. We found 2D-global LV longitudinal stains (GLS) recovered -17.2(-16.2- -18.3)% versus (-12.4(-11.7- -14.3)%; P<.001) at follow-up cardiac MRI as compared to baseline. There was no differences (-17.2(-16.2 - -18.3)% vs-15.4(-14.3- -17.8)%; P=.134) between follow-up and health controls. 2D global radial strain (GRS) and 2D global circumferential strain (GCS) showed no differences among these groups (p=.476, p=.921, respectively)Interpretation: CMR myocardial tissue and strain imaging parameters suggest that subclinical myocardial tissue characteristic abnormalities in individuals without cardiac symptoms or clinical findings of myocardial injury persists in 30% at 300 days.Funding: Supported in part by the Anhui Natural Science Foundation (202004a0702003, 201904a07020060). Fuyang Natural Science Foundation (FK20202815-3). National Natural Science Foundation of China (82071897,81970446).Declaration of Interest: None to declare. Ethical Approval: The study was approved by the local Institutional Ethics Committee (PJ2020-02-10).