Impact of intracoronary bone marrow cell transfer on diastolic function in patients after acute myocardial infarction: results from the BOOST trial

AIMS: We have recently shown in the randomized-controlled BOne marrOw transfer to enhance ST-elevation infarct regeneration (BOOST) trial that intracoronary autologous bone marrow cell (BMC) transfer improves left ventricular (LV) ejection fraction recovery in patients after acute myocardial infarction (AMI). However, the impact of BMC therapy on LV diastolic function in patients after AMI has remained uncertain. METHODS AND RESULTS: Using (tissue) Doppler echocardiography, we evaluated the effects of BMC transfer on LV diastolic function in patients enrolled in the BOOST trial. After successful primary percutaneous coronary intervention (PCI) for acute ST-elevation myocardial infarction (MI), patients were randomized to a control (n = 29) or BMC transfer group (n = 30). Diastolic function was determined 4.5+/-1.5 days after PCI, at 6 months, and at 18 months by measuring transmitral flow velocities (E/A ratio), diastolic myocardial velocities (Ea/Aa ratio), isovolumic relaxation time (IVRT), and deceleration time (DT). All analyses were performed in a blinded fashion. There was an overall effect of BMC transfer on E/A [0.33+/-0.12; 95% confidence interval (CI): 0.09-0.57; P = 0.008] and Ea/Aa ratios (0.29+/-0.14; 95% CI: 0.01-0.57; P = 0.04). In contrast, we found no effect of BMC transfer on DT (-5+/-14 ms; 95% CI: -33 to 22; P = 0.70), IVRT (-7+/-7 ms; 95% CI: -20 to 6; P = 0.29), and E/Ea ratio (0.35+/-0.14; 95% CI: -0.92 to 1.62; P = 0.57). CONCLUSION: Intracoronary autologous BMC transfer improves echocardiographic parameters of diastolic function in patients after AMI.