Severe hypoxemia in a patient with right ventricular myocardial infarction and SARS-CoV-2 infection

Background: Refractory hypoxemia after right ventricular myocardial infarction and concomitant SARS-CoV-2 infection represents an uncommon, yet particularly challenging clinical scenario. We report a challenging diagnostic case of refractory hypoxemia due to right-to-left shunt highlighting contemporary challenges and pitfalls in acute cardiovascular care associated with the current COVID-19 pandemic. Case presentation: A 52-year-old patient admitted for inferior acute myocardial infarction developed rapidly worsening hypoxemia shortly after primary percutaneous coronary intervention. RT-PCR screening for SARS-CoV-2 was positive, even though the patient had no prior symptoms. A computed tomography pulmonary angiogram excluded pulmonary embolism and showed only mild interstitial pulmonary involvement of the virus. Transthoracic echocardiogram showed severe right ventricular dysfunction and significant right-to-left shunt at the atrial level after agitated saline injection. Progressive improvement of right ventricular function allowed weaning from supplementary oxygen support. Patient was latter discharged with marked symptomatic improvement. Conclusion: Refractory hypoxemia after RV myocardial infarction should be carefully addressed, even in the setting of other more common and tempting diagnoses. After exclusion of usual etiologies, right-to-left shunting at the atrial level should always be suspected, as this may avoid unnecessary and sometimes harmful interventions.