Massive Pulmonary Thromboembolism Mimicking Acute Coronary Syndrome: Diagnostic Relevance of the Daniel ECG Score: A Case Report

Aims: To highlight the potential diagnostic value of the Daniel electrocardiographic score in recognising severe pulmonary thromboembolism when its clinical presentation mimics acute coronary syndrome. Presentation of Case: A 67-year-old woman presented with dyspnoea, chest pain and weakness. Twenty days earlier, she had sustained a leg injury followed by reduced mobility. On admission, blood pressure was 90/60 mmHg, heart rate 109 beats/min and oxygen saturation 90% on room air. Electrocardiography showed sinus tachycardia, S1Q3T3, incomplete right bundle branch block, and T-wave inversion in leads III, aVF and V1 – V5. The Daniel electrocardiographic score was 18. Troponin I increased from 470 to 1132 pg/mL, N-terminal pro-B-type natriuretic peptide was 11,749 pg/mL and D-dimer was 20 mg/L. Echocardiography demonstrated right ventricular dilatation with reduced systolic function. Venous Doppler confirmed right popliteal deep-vein thrombosis. Computed tomography pulmonary angiography demonstrated extensive thrombus involving the left main pulmonary artery and lobar branches. Discussion: Chest pain, hypotension and elevated troponin initially raised concern for acute coronary syndrome. However, the high Daniel score and electrocardiographic signs of right ventricular strain prompted evaluation for pulmonary thromboembolism. The patient was treated according to contemporary recommendations. At one-month follow-up, the electrocardiographic and echocardiographic abnormalities had resolved, with near-complete regression of thrombotic obstruction. Conclusion: The Daniel electrocardiographic score may be a useful bedside clue to severe pulmonary thromboembolism, particularly when its presentation mimics acute coronary syndrome. It should complement, rather than replace, clinical assessment and definitive imaging.