COVID-19
Authors: Daniel S. Knight, Tushar Kotecha, Yousuf Razvi, Liza Chacko, James T. Brown, Paramjit S. Jeetley, James Goldring, Michael Jacobs, Lucy E. Lamb, Rupert Negus, Anthony Wolff, James C. Moon, Hui Xue, Peter Kellman, Niket Patel, Marianna Fontana
Journal: Circulation (2020)

◼ gadolinium ◼ magnetic resonance imaging ◼ myocarditis ◼ severe acute respiratory syndrome coronavirus 2 ◼ troponin H ospitalized patients with coronavirus disease 2019 (COVID-19) frequently have myocardial injury with troponin elevation, 1-4 but the underlying causes beyond acute coronary syndromes and pulmonary emboli are ill defined.We used cardiovascular magnetic resonance (CMR) during early convalescence to assess the presence, type, and extent of myocardial injury in troponin-positive patients with COVID-19.All patients with COVID-19 discharged from the Royal Free London NHS Foundation Trust until April 30, 2020 were reviewed (Figure).Diagnosis was either by (1) positive oro/nasopharyngeal throat swab for severe acute respiratory syndrome coronavirus 2 by reverse transcriptase polymerase chain reaction or (2) negative swabs for severe acute respiratory syndrome coronavirus 2 but the triad of viral illness symptoms (≥1 of cough, fever, myalgia), typical blood biomarkers (≥1 of new lymphopenia, high d-dimer, high ferritin, elevated liver transaminases), and probable likelihood of COVID-19 infection on thoracic imaging.A CMR scan (1.5T, Magnetom Aera, Siemens Healthcare) was offered to patients discharged with a COVID-19 diagnosis and myocardial injury as indicated by elevated high-sensitivity troponin T (hsTnT, >14 ng/L).Exclusions were hospitalization with acute coronary syndromes or pulmonary emboli, known cardiac pathology likely to cause scar, age ≥80 years, severe renal impairment, pregnancy, medical unsuitability, and standard CMR contraindications.CMR included cines, native myocardial T1 and T2 mapping, early and late gadolinium enhancement (LGE) with, if no contraindications, adenosine stress perfusion imaging.The CMR diagnosis of myocarditis followed published expert recommendations. 5Ethical approval was obtained (London Hampstead Research Ethics Committee, reference 19/LO/1561), and all patients provided written informed consent.The majority (71%) of the 828 reverse transcriptase polymerase chain reactionpositive patients had elevated hsTnT, which was associated with higher inpatient mortality (elevated versus normal hsTnT: 239/586 [41%] died versus 20/242 [8%], respectively, P<0.001).Fifty-one patients were referred for CMR, 22 of whom had ≥1 identifiable causes of troponin elevation (6 with acute coronary syndromes, 12 with pulmonary emboli) or known cardiac pathology (7 had a history of ischemic heart disease) or both.The remaining 29 patients who were included in the final analysis had unexplained myocardial injury and no cause for previous myocardial scarring, 19 of whom (66%) underwent additional adenosine stress perfusion.The intervals between CMR and symptom onset, diagnosis, or discharge were 46±15 days, 37±10 days, and 27±11 days, respectively.Of the 29 patients with elevated hsTnT of unknown cause (average age 64±9 years), most were male (24, 83%) and were reverse transcriptase polymerase chain reaction positive (28, 97%).Median inpatient stay was 9 days (6-16), and 10 (34%) patients required intensive care unit ventilatory support.