Recurrent Syncope in a Young Adult with Exercise Intolerance

Case at a Glance

A 24-year-old male presents with recurrent episodes of syncope, progressive exercise intolerance, and dyspnea on exertion over a 4-month period, ultimately diagnosed with hypertrophic cardiomyopathy and ventricular tachycardia.

Patient's Story

The patient is a 24-year-old Caucasian male with no significant known medical history who experienced his first syncopal episode 4 months prior while at home. The episode was preceded only by fatigue, with no other prodromal symptoms. Initial emergency department evaluation included an ECG which was reported as normal but tachycardic, attributed to anxiety. Four months later, while engaged in heavy lifting, the patient developed acute onset of severe fatigue and dyspnea, followed by dizziness and a second syncopal episode. Emergency medical services evaluated him at the scene, reporting normal oxygen saturation. The following day, he complained of persistent fatigue and dyspnea at rest despite remaining sedentary.

Initial Assessment

Physical examination findings were not documented in detail. Vital signs from EMS showed normal oxygen saturation post-syncope. The patient appeared to have exercise-induced symptoms with dyspnea on exertion progressing to dyspnea at rest. Initial ECG 4 months prior was documented as showing sinus tachycardia.

The Diagnostic Journey

Given the recurrent nature of syncope, exercise intolerance, and progressive symptoms, the patient was advised to seek emergency care despite his reluctance. Cardiac workup was initiated including repeat ECG, echocardiography, and cardiac biomarkers (troponin, creatine kinase). The diagnostic evaluation revealed significant cardiac abnormalities requiring immediate intervention.

Final Diagnosis

Hypertrophic cardiomyopathy with left bundle branch block (LBBB) and ventricular tachycardia (VT). Genetic testing was initiated to confirm suspected genetic etiology of the cardiomyopathy.

Treatment Plan

The patient was started on cardiac medications for heart failure management and arrhythmia control. Given the life-threatening nature of ventricular tachycardia and risk of sudden cardiac death, an implantable cardioverter-defibrillator (ICD) was recommended and planned for insertion. Genetic counseling was provided, though family screening was limited due to the patient's adoption status.

Outcome and Follow-up

The patient's condition was stabilized with medical therapy. The diagnosis likely prevented sudden cardiac death, as ventricular tachycardia can degenerate into ventricular fibrillation. Long-term management will include regular cardiology follow-up, activity restriction as appropriate, and ICD monitoring. The case highlights the importance of investigating recurrent syncope in young adults, as it may indicate serious underlying cardiac pathology.