Tachycardia as an Early Clinical Sign of Pulmonary Embolism: A Case of Unprovoked Massive Bilateral Pulmonary Embolism “Saddle’’ Embolismin a Young Adult

Abstract Pulmonary embolism (PE) is a potentially fatal condition presenting with various symptoms. Typical features include sudden-onset dyspnea, pleuritic chest pain, and hemoptysis; however, atypical presentations may delay diagnosis. A massive PE caused by a saddle thrombus at the pulmonary trunk bifurcation—as in our case—may present with syncope, presyncope, hypotension, and can progress to circulatory collapse and shock. We present a 47-year-old female with bronchial asthma who presented with sore throat and shortness of breath. Despite lacking traditional risk factors or symptoms, a borderline unexplained tachycardia (HR 105 bpm) prompted further workup. Elevated D-dimer and CT pulmonary angiography identified a massive bilateral saddle embolus with right heart strain. The patient underwent thrombolysis and recovered fully. This case highlights the critical importance of considering tachycardia as a sole early PE indicator in the emergency setting.