Newsletter Edition October 2020 - Corner Case -1​

Contributed by Dr Priya Chudgar
Jupiter Hospital,
Thane, Mumbai

A 46-year-old gentleman, euglycemic and normotensive, presented with fever and respiratory complaints and was diagnosed with COVID-19 infection in June 2020. Post recovery, as defined by the state guidelines then, he was discharged. The day after his discharge, he returned to the hospital with acute chest pain and chest tightness. ECG findings (Fig 1) and Troponin levels were consistent with acute myocardial infarction. After initial conservative management, he underwent CT coronary angiography two weeks post-presentation for further evaluation. 

Figure 1: ECG revealed ST-segment elevation.

Findings:

CT coronary angiography performed on 128 Slice MDCT Scanner (Fig 2). It revealed a calcium score of 3 by the Agatson scoring system, and an eccentric mixed density plaque in proximal Left anterior descending coronary artery (LAD) close to the ostium of the 1st diagonal artery (D1) causing m ild (40-50%) luminal stenosis. The distal LAD was unremarkable.  The circumflex and right coronary artery revealed no plaques or stenosis.

Lung window images of the same patient revealed multiple patchy confluent areas of ground-glass densities in both lungs. These were associated with curvilinear subpleural atelectatic changes in lower lobes. Imaging features are consistent with COVID-19 infection (Fig 3).

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(b)

(c)

Fig 2.
Axial (a) and multiplanar reconstructions (b) and volume rendered images (c) of CT Coronary angiography reveal eccentric mixed density plaque in the proximal LAD.(Thin white arrow in image a points towards plaque)

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(b)

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Fig 3.
Lung windows reveal patchy confluent ground glass densities in both lungs, consistent with COVID-19 infection. (Thin white arrow in image c points towards abnormality)
Discussion:

COVID-19 infection is the clinical disease caused by SARS-CoV-2 virus. The presentation of COVID-19 can range from patients being asymptomatic to pneumonia and acute respiratory distress syndrome. Myocardial injury, is also common in COVID-19 infection, has a poor prognosis irrespective of the cause.  Myocardial injury, defined by a raised troponin level, can occur in patients with or without a prior cardiovascular diagnosis. Patients with co-morbidities such as diabetes mellitus, hypertension, cardiovascular disease and obesity are at a higher risk for poorer prognosis.

Patients with acute infection, whether viral or bacterial, are known to have increased inflammatory prothrombotic and procoagulant responses.1 Patients infected with the virus SARS-CoV-2 and its clinical disease COVID-19 are often minimally symptomatic or asymptomatic. More severe presentations include pneumonia and acute respiratory distress syndrome. Possible mechanisms may include stress-related such as hypoxic injury, stress cardiomyopathy and systemic inflammatory response syndrome (aka cytokine storm), or ischemic injury (caused by microvascular injury or coronary artery disease). However, only a small number of these patients present with an acute coronary syndrome.

The Fourth Universal Definition of MI includes a clinical classification according to the assumed proximate cause of the myocardial ischemia.
●Type 1: MI caused by acute atherothrombotic CAD and usually precipitated by atherosclerotic plaque disruption (rupture or erosion).
●Type 2: MI consequent to a mismatch between oxygen supply and demand.

With COVID-19 infection, the majority of MIs are type 2 due to the primary infection-related hemodynamic and respiratory derangement and can be conservatively managed. If a type 1 MI is thought to be the aetiology, standard therapies have to be considered.

In the current case, the patient was athletic and otherwise healthy and had no co-morbidities or cardiovascular risk factors. He had an MI while recovering from the viral illness and therefore, was conservatively managed.

Learning point: This case is a lucid representation of the utility of coronary CT angiography in determining the cause of myocardial injury and a reminder that cardiovascular complications can occur in the COVID-19 population, even in those patients with minimal risk factors for heart disease.

References:

  1. Juthani P, Bhojwani R, Gupta N. Coronavirus Disease 2019 (COVID-19) Manifestation as Acute Myocardial Infarction in a Young, Healthy Male. Case Rep Infect Dis. 2020;2020:8864985. Published 2020 Jul 11. DOI:10.1155/2020/8864985
  2. Bonow RO, Fonarow GC, O’Gara PT, Yancy CW. Association of Coronavirus Disease 2019 (COVID-19) With Myocardial Injury and Mortality. JAMA Cardiol. 2020;5(7):751–753. DOI:10.1001/jamacardio.2020.1105