A case of novel coronavirus (COVID-19)-induced viral myocarditis mimicking a Takotsubo cardiomyopathy

The patient’s medical history was notable for hypertension, hyperlipidemia, and hypothyroidism.

The differential diagnosis of acute dyspnea with hypoxia in a 73-year-old woman is broad. COVID-19-induced acute respiratory distress syndrome was a major concern. Other differential diagnoses were acute pulmonary embolism, acute heart failure, septic shock, cardiac tamponade, acute coronary syndrome, viral pneumonia from other pathogens, bacterial pneumonia, and viral cardiomyopathy.

Results of laboratory testing during initial hospital admission were the following: potassium 2.2 mEQ/L (3.5–5.0 mEQ/L), creatinine 1.79 mg/dL (0.7–1.3 mg/dL), C-reactive protein 23.10 mg/L (0.0–0.8 mg/dL), interleukin-6 (IL-6) 781.46 mg/L (0–12.4 mg/L), lactate dehydrogenase 334 U/L (60–100 U/L), ferritin 457 ng/mL (15–200 ng/mL), procalcitonin 15.20 ng/mL (0.10–0.49 ng/mL), prothrombin time 18.9 seconds (11–13 seconds), fibrinogen >600 mg/dL (150–350 mg/dL), white blood cell count 16.1 cells/L (4000–10,000 cells/μL) with 92.7% neutrophils, IgG 1622 mg/dL (700–1600 mg/dL). The patient tested positive for SARS-CoV-2. Initially, the troponin was 0.03 ng/dL; however, high-sensitivity troponin peaked later in the hospital course at 503 ng/L (<14 ng/L for women) and proBNP was 35,000 pg/mL (<450 pg/mL). These values indicated extraordinarily high levels of these serum enzymes. A chest radiograph showed diffuse bilateral pulmonary edema vs infiltrates (Supplemental Figure 1). A repeat chest radiograph revealed worsening diffuse bilateral pulmonary opacities/infiltrates vs edema (Figure 1). An electrocardiogram showed no signs of ischemia, normal sinus rhythm with a short PR interval of 72 ms, left ventricular (LV) hypertrophy, and a QTc interval of 680 ms (Supplemental Figure 2). Previous echocardiograms from prior hospitalizations and initially on admission showed a normal LV ejection fraction (LVEF) and no wall motion abnormalities. Now, a transthoracic echocardiogram (TTE) revealed a severely decreased LV systolic function with segmental wall motion abnormalities, akinesis of the distal segments of the left ventricle with relatively preserved function at the base, and akinesis of the mid and distal portions of the right ventricle with preserved function at the base of the free wall as well as an ejection fraction (EF) of 25%–30% (normal range >50%) (Figure 2, Supplemental Figure 3, Supplemental Videos 1–3).

The patient was intubated for respiratory distress and hypoxic respiratory failure. At that time, a limited bedside TTE was conducted to evaluate the thoracic structures and overall hemodynamic state of the patient, which revealed a normal cardiac EF of 55%. She was found to be in a shock state and required vasopressor support with norepinephrine. This was followed by initiation of the ARDSnet protocol. The patient was treated with 2 doses of tocilizumab (480 mg and 240 mg), intravenous immunoglobulin (25 g for 5 days), ceftriaxone, cefdinir, and cefepime owing to cytokine storm from COVID-19 and leukocytosis. She was not treated with hydroxychloroquine or azithromycin owing to a prolonged QTc interval.

A repeat chest radiograph (Figure 1) revealed worsening bilateral airspace opacities vs vascular congestion, so the patient was treated with intravenous furosemide 40 mg. At this time, cardiac enzymes were found to be elevated. A repeat bedside TTE was performed and revealed an LVEF of 20%–25%. The resulting findings created concern for severe viral myocarditis, so the patient was transferred to a tertiary center for possible advanced management. At the facility, a complete 2D echocardiogram revealed an LVEF of 25%–30% along with wall motion abnormalities (Supplemental Videos 1–3). Her non-ST-elevation myocardial infarction was suspected to be secondary to a viral cardiomyopathy, but she was treated with therapeutic enoxaparin as a precaution.

After completion of tocilizumab, and within 2 days of completing intravenous immunoglobulin, her LVEF recovered to 50% on TTE, with overall mildly reduced LV systolic function, mid-septal and apical hypokinesis, and mildly reduced right ventricular function (Figure 3, Supplemental Figure 4, Supplemental Videos 4–6). Blood and respiratory cultures were negative. Inflammatory markers greatly improved but then worsened again. IL-6, however, continued to downtrend from 781.46 mg/L to 171.82 mg/L 2 days after the completion of treatment. A decrease in the level of high-sensitivity troponin from 503 ng/L to 418 ng/L was also observed. She was not a candidate for extracorporeal membrane oxygenation owing to her advanced age. After improvement of her LVEF, the patient was transferred back to our intensive care unit.