Abstract
Patients with paroxysmal nocturnal hemoglobinuria (PNH) have transient attacks of complement-mediated hemolysis and thrombosis that can be spontaneous or secondary to precipitating factors such as infections. We present a case of a 63-year-old male patient with a medical history of PNH who presented with typical chest pain, fever, cough, jaundice, and dark-colored urine. On examination, he was hemodynamically stable but had conjunctival icterus. A few minutes after presentation, the patient suffered a ventricular fibrillation cardiac arrest and then achieved a return of spontaneous circulation after receiving two defibrillator shocks. EKG showed inferior wall ST-segment elevation myocardial infarction. Labs showed hemoglobin of 6.4 g/dl, elevated cardiac markers, serum lactate dehydrogenase, and indirect bilirubin. Serum haptoglobin was < 1 mg/dl. His COVID-19 polymerase chain reaction test was positive. Immediately, the patient received 2 units of packed RBCs and underwent a coronary angiogram (CA), which revealed total proximal occlusion of the right coronary artery. He underwent successful percutaneous coronary intervention (PCI), and two drug-eluting stents were placed. His peripheral blood immunophenotyping and flow cytometry showed loss of glycosylphosphatidylinositol-linked antigens and decreased expression of CD 59/14/24. He was started on ravulizumab, a humanized monoclonal antibody complement five inhibitor. Both PNH and COVID-19 increase the risk of thrombosis. Endothelial injury and cytokine storm increase the risk of thrombosis in COVID-19 patients, whereas the activation of the coagulation system and the impairment of the fibrinolytic system by complement cascade leads to thrombosis in PNH patients. Regardless of which pathway leads to coronary artery thrombosis, CA and PCI can be life-saving.