Impact of Cell Therapy on Myocardial Perfusion and Cardiovascular Outcomes in Patients With Angina Refractory to Medical Therapy: A Systematic Review and Meta-Analysis
Rationale: The effect of stem/progenitor cells on myocardial perfusion and clinical outcomes in patients with refractory angina (RFA) remains unclear because studies published to date have been small phase I-II trials.
Objective: We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of cell-based therapy in patients with RFA who were ineligible for coronary revascularization.
Methods and Results: Several data sources were searched from inception till September 2015, which yielded six studies. The outcomes pooled were indices of angina (anginal episodes, Canadian Cardiovascular Society [CCS] angina class, exercise tolerance, anti-anginal medications), myocardial perfusion, and clinical end-points. We combined the reported clinical outcomes (myocardial infarction, cardiac-related hospitalization, and mortality) into a composite end-point (MACE). Mean difference (MD), standardized mean differences (SMD), or odds ratio (OR) were calculated to assess relevant outcomes. Our analysis shows an improvement in anginal episodes (MD -7.81;95% CI, -15.22−-0.-41), use of anti-anginal medications (SMD -0.59;CI, -1.03−-0.14), CCS class (MD -0.58;CI, -1.00−-0.16), exercise tolerance (SMD 0.331;CI, 0.08−0.55), and myocardial perfusion (SMD -0.49;CI, -0.76−-0.21) and a decreased risk of MACE(OR 0.49;CI, 0.25−0.98) and arrhythmias(OR 0.25; 95% CI, 0.06−0.98)in cell-treated patients compared with patients on maximal medical therapy.
Conclusions: The present meta-analysis indicates that cell-based therapies are not only safe but also lead to an improvement in indices of angina, relevant clinical outcomes, and myocardial perfusion in patients with RFA. These encouraging results suggest that larger, phase III RCTs are in order to conclusively determine the effect of stem/progenitor cells in RFA.
- Received November 22, 2015.
- Revision received January 4, 2016.
- Accepted January 13, 2016.