Efficacy and Safety of Stem Cell Therapy in Advanced Heart Failure Patients: A Systematic Review with a Meta-analysis of Recent Trials Between 2017 and 2019

Objective The effects of stem cell therapy in patients with advanced heart failure is an ongoing debate. This study aimed to assess the effectiveness and safety of stem cell therapy plus the standard of care as compared to the placebo plus the standard of care in advanced heart failure patients. Methods A comprehensive keyword search of PubMed between 2017 and 2019 was performed to extract trials conducted with stem cell therapy controlled with placebo in advanced heart failure. We included randomized controlled trials (RCTs) with data on safety and efficacy in patients with advanced heart failure after stem cell transplantation. Results Six RCTs, consisting of 569 patients, were selected. Three-hundred sixty-seven (367) out of 369 participants from the eligible four out of six RCTs were included for efficacy analysis, as we lost two patients from the final analysis due to early death. Five-hundred twenty-six (526) out of 527 participants from the eligible five out of six RCTs were included for safety analysis, as we lost one patient from the final analysis for not being able to receive the intervention. Stem cell transplantation significantly improved left ventricular ejection fraction (LVEF) by 4.58% (95% CI: 3.73-5.43%; p = 0.00001), improved left ventricular end-systolic volume (LVESV) by -5.18 ml (95% CI: -9.74 to -0.63 ml; p =0.03), and there was no difference in the risk of all-cause mortality (OR 0.97; 95% CI: 0.52 to 1.78%; p = 0.91). The above results correlate with the previous meta-analysis data conducted in 2016. Conclusions This meta-analysis provided the cumulative efficacy and safety results of stem cell transplantation in advanced heart failure based on recent RCTs. The above results suggest that stem cell therapy was associated with a moderate improvement in LVEF, and the safety analysis indicates no increased risk of mortality in patients with advanced heart failure. This meta-analysis recommends conducting more RCTs comparing stem cell transplantation and placebo with a larger patient population and longer follow-up.