Subacute pulmonary embolism mimicking acute heart failure, acute coronary syndrome and pneumonia: A case report

Abstract Background Venous thromboembolism, encompassing deep vein thrombosis (DVT) and pulmonary embolism (PE), is a potentially condition that is frequently misdiagnosed. PE is the third leading cause of cardiovascular death worldwide, commonly arises from dislodged thrombi and occludes the pulmonary circulation. It may mimic acute heart failure (AHF), acute coronary syndrome (ACS), or pneumonia, leading to delayed diagnosis and increased morbidity and mortality. Case Illustration A 57-year-old man initially suspected of AHF, ACS, and pneumonia but was subsequently diagnosed with subacute PE. He reported one month of progressive dyspnoea, dry cough, history of fever, no haemoptysis, non-specific chest pain, with prior hospitalisations for presumed pulmonary infections without improvement. Oxygen saturation was 90% on room air. Electrocardiography demonstrated right ventricular strain with an S1Q3T3 pattern. Chest radiography demonstrated cardiomegaly and pulmonary congestion. Laboratory tests revealed elevated high-sensitivity troponin I and NT-pro BNP, with markedly elevated D-dimer. Echocardiography showed left ventricular D-shaped configuration, right heart dilatation. Computed tomography pulmonary angiography confirmed bilateral pulmonary artery thrombi. The patient received intravenous heparin followed by catheter-directed thrombolysis with alteplase. Angiography demonstrated high pulmonary artery pressures and filling defects. Duplex ultrasonography identified thrombi in the upper and lower extremity veins despite low clinical probability for DVT. Follow-up demonstrated significant clinical improvement, right ventricular recovery, and reduced pulmonary artery pressure. The patient was discharged on oral anticoagulant with complete symptom resolution. Conclusion PE may mimic other cardiopulmonary conditions, necessitating high clinical suspicion and prompt multimodal evaluation to ensure accurate diagnosis and timely management to improve clinical outcomes.Figure 1.Multimodality data findings of the patient. (A) Electrocardiography. (B) Chest radiography. (C) Transthoracic echocardiography. (D) Duplex ultrasonography. (E) Computed tomography pulmonary angiography. (F) Pulmonary angiography.