Dr. Neil Riordan on health: what the evidence says · JRE #1066
“The BMP came down in every single case. The ejection fraction, which measures kind of like the efficiency, how much blood your heart's pumping on each stroke, went up in every single patient.”
What the evidence says
Riordan claimed that in stem-cell trials for heart failure, a biomarker (likely BNP, brain natriuretic peptide) fell and ejection fraction rose in every single treated patient. The best available synthesis of controlled evidence, a 2016 Cochrane systematic review and meta-analysis of 38 randomized controlled trials (1,907 participants) of autologous bone-marrow-derived stem/progenitor cells in chronic ischemic heart disease and congestive heart failure, found only low-quality evidence of a modest average improvement in left ventricular ejection fraction, with wide confidence intervals. In the long-term MRI-measured subgroup, the mean difference in ejection fraction was -1.60 (95% CI -8.70 to 5.50, n=25), not statistically distinguishable from zero. The Cochrane authors explicitly cautioned that findings should be interpreted with caution given low event rates and imprecision, which is inconsistent with a uniform 100% response across patients. Universal, exceptionless improvement in both a natriuretic peptide biomarker and ejection fraction has not been demonstrated in peer-reviewed controlled trials; individual patient variability in response is the norm in this literature, not the exception. Ejection fraction is a standard, well-defined measure of heart pumping efficiency, so the claim's description of the metric is accurate, but the assertion of a universal (100%) responder rate across trials is not supported by the controlled-trial evidence base.