Electrocardiographic screening for hypertrophic cardiomyopathy and long QT syndrome: the drivers of cost-effectiveness for the prevention of sudden cardiac death.

It is universally recognized that the prevention of sudden cardiac death (SCD) in youth is an important public health initiative. The best approach remains uncertain. Many European and Asian countries support the use of electrocardiograms (ECGs). In the United States, this is highly controversial. Many debate its cost-effectiveness. We designed a comprehensive economic model of two of the most prevalent causes of SCD identifiable by ECG, hypertrophic cardiomyopathy (HCM) and long QT syndrome (LQTS), to determine the drivers of uncertainty in the estimate of cost-effectiveness. We compared the cost-effectiveness of screening with history and physical examination (H&P) plus ECG to the current United States standard, H&P alone, for the detection and treatment of HCM and LQTS. We used a Markov model on a theoretical cohort of healthy 12-year-olds over a 70-year time horizon from a societal perspective, employing extensive univariable and probabilistic sensitivity analyses, to determine drivers of costs and effectiveness. The incremental cost-effectiveness of adding ECGs to H&Ps was $41,400/life-year saved. The model was highly sensitive to the effect of identification and treatment of previously undiagnosed individuals with HCM; however, it was insensitive to many variables commonly assumed to be significant, including the costs of ECGs, echocardiograms, and genetic testing, as well as the sensitivity and specificity of ECGs. No LQTS-related parameters were significant. This study suggests that the key to determining the cost-effectiveness of ECG screening in the United States lies in developing a better understanding of disease progression in the previously undiagnosed HCM population.