Features of T wave inversion and diagnosis of cardiomyopathy: relevance for a cardiac screening programme in young individuals

AIMS: To determine the clinical significance of T wave depth and T wave/QRS voltage ratio in young individuals who exhibit TWI on ECG performed as part of cardiac screening. METHODS: We analysed an electronic database of individuals aged 14-35 years who underwent voluntary cardiac screening between 2008 and 2013. The prevalence of TWI, the lead distribution, the T wave depth and the T wave/QRS voltage ratio were assessed. Follow-up information was available for all subjects, including data regarding diagnosis of cardiac disease and major cardiac events. RESULTS: The cohort consisted of 5360 individuals and TWI was documented in 120 (2%) cases. After further investigations, a diagnosis of cardiomyopathy was made in 16 cases. Individuals who were eventually diagnosed with cardiomyopathy exhibited more frequently TWI in multiple territories than individuals who did not receive a diagnosis at follow-up. T waves were deeper (p=0.03) in the former compared to the latter, but no significant difference in T/QRS ratio was observed. The cut-off value of TWI depth that best differentiated between presence and absence of cardiomyopathy was 0.183 mV; ROC curve analysis showed an AUC of 0.767. During a mean follow-up of 8.1±1.2 years, no deaths were documented, but 3 of the 16 patients experienced a sudden cardiac arrest (all of them were diagnosed with arrhythmogenic cardiomyopathy). CONCLUSIONS: T wave inversion is a relatively common ECG finding in young apparently healthy individuals. The distribution on multiple lead territories and deeper T waves are early indicators of an underlying cardiomyopathy.