SCD-HeFT /MASTER Review Summary:

SCD-HeFT and MASTER are not new.	Results of both MASTER and SCD-HeFT have been in the public domain for some time now.  MASTER was presented at AHA last year, and SCD-HeFT was presented at AHA in 2006.
SCD-HeFT has one of the highest indeterminate rates of any study published to date.	One of the most noted limitations of the SCD-HeFT trial is the high indeterminate rate (41%).  This is more than twice the rate of other published studies including Chow (21%), Ikeda (9%) and ALPHA (21%).  Such a high indeterminate rate calls into question the overall quality of the MTWA data.
The SCD-HeFT study can be interpreted as positive for MTWA.	Per Dr. Rosenbaum’s editorial, the SCD-HeFT study shows that the Kaplan-Meier curves for MTWA start to separate when the mortality curves from the main study begin to separate.  This suggests that “a TWA signal of risk closely corresponded with emergence of the SCD phenotype in this population.”
Both studies use ICD shocks as a surrogate endpoint for SCD.	In clinical trials, ICD shocks, even those deemed appropriate, have been shown to outnumber SCD events by a factor of 2 to 3.  Such data shows that ICD shocks are not an optimal surrogate endpoint for SCD.  This is discussed in the MASTER publication and is the main topic of several other studies.