年青人運動時心臟不適引起的猝死不常發生，但往往令人措手不及而悲劇收場。此狀況通常在劇烈運動一小時內發作，主要致命機轉是：因劇烈運動而導致血行動力學或電生理學的改變。最常見的死因為致命性心室性心律不整。其中較常見的死因為肥厚性心肌病(Hypertrophy cardiomyopathy)及心律不整右心室心肌病(Arrythmogenic right ventricular cardiomyopathy),但也有少數病例為無心臟病史而發生的運動心因性猝死。本篇報告敘述一個19歲男性，因進行三千公尺的跑步，突然休克倒下，經CPR急救後，再轉送到本院CCU。到院時心電圖呈現心室頻脈，經電擊治療後，心律恢復正常，但因休克過久，最後因併發多重器官衰竭而過世。在病理解剖方面，除了體腔積水、肺水腫、腦部分區域蜘蛛膜下腔出血，以及肝、腎衰竭以外，主要在顯微鏡觀察下，發現心臟左心室心肌排列有不規則現象。以本病例而言，沒有任何心臟病史的年青人也可能發生運動性心因性猝死。此病例與常見無心臟病史病例所造成的運動性心因性猝死有所不同，可觀察到病理解剖上心臟左心室心肌排列有不規則現象，為其造成左心室頻脈最可能的死因。
Exercise-related sudden cardiac death (SCD) is defined by symptoms that arise within 1 hour of participation in an athletic event. The major mechanisms involved in exercise-related SCD are related to hemodynamic and electrophysiological changes caused by exercise in the susceptible individual. Fatal ventricular arrhythmia is the most common mechanism of death. In young adults (<35 years old), the majority of SCDs are caused by defined and hereditary cardiovascular disorders. Among other etiologies, hypertrophy cardiomyopathy and coronary artery anomalies are the most common. But different ventricular tachyarrhythmias may cause syncope or cardiac arrest in patients without known heart diseases. Few exercise-related sudden cardiac deaths due to ventricular tachycardia originated from irregular muscle arrangement in left ventricle myocardium had been reported. We described a 19 years old male without history of heart disease who developed sudden cardiac death during exercise. Ventricular tachycardia was noted at that time and ECG pattern at the beginning was the same as the pattern of "idiopathic left ventricular tachycardia" in electrophysiological study. Post mortem diagonosis revealed irregular muscle arrangement in left ventricle myocardium was the only specific. Exercise related sudden cardiac death of young adult without history of heart disease, ventricular tachycardia was always the etiology and some of which were very likely related to irregular muscle arrangement in left ventricle myocardium.
