What electrocardiogram (ECG) finding is suggestive of underlying cardiac disease in a 20-year-old football player: T wave inversion in leads V1-V5, voltage criteria for left ventricular hypertrophy (LVH), Wenkebach phenomenon (Mobitz type I second-degree atrioventricular (AV) block), dominant R wave in lead V1, or junctional rhythm with bradycardia at rest?

Differential Diagnosis for Cardiac Disease in a 20-year-old Football Player

Single most likely diagnosis

• Hypertrophic Cardiomyopathy (HCM): T wave inversion in V1-V5 and voltage criteria for left ventricular hypertrophy are suggestive of HCM, a common cause of sudden cardiac death in young athletes. The presence of these ECG findings, especially in the context of a young athlete, warrants further investigation for HCM.

Other Likely diagnoses

• Left Ventricular Hypertrophy (LVH): Voltage criteria for LVH can be seen in various conditions, including hypertension, aortic stenosis, and athletic heart syndrome. While LVH itself is not necessarily a disease, it can be a marker for underlying conditions that need to be evaluated.
• Athletic Heart Syndrome: This condition, characterized by physiological adaptations to exercise, can include ECG changes such as T wave inversion and increased QRS voltages. However, it's crucial to differentiate this from pathological conditions like HCM.

Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)

• Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): Although less common, ARVC can present with T wave inversion in the right precordial leads (V1-V3) and is a significant cause of sudden cardiac death in young people. It's essential to consider ARVC in the differential diagnosis due to its potential lethality.
• Long QT Syndrome: While not directly suggested by the provided ECG findings, long QT syndrome is a condition that can lead to sudden cardiac death and should be considered in any young athlete undergoing cardiac evaluation, especially if there's a family history or symptoms suggestive of the condition.

Rare diagnoses

• Cardiac Sarcoidosis: This condition can cause various ECG abnormalities, including T wave inversion and arrhythmias. While rare, it's an important consideration in the differential diagnosis due to its potential for significant morbidity and mortality.
• Myocarditis: Inflammation of the heart muscle can result in ECG changes, including T wave inversion. Myocarditis is a rare but potentially serious condition that could be considered if other findings or symptoms are present.