Predictors of ventricular remodelling in patients with reperfused acute myocardial infarction and left ventricular dysfunction candidates for bone marrow cell therapy: insights from the BONAMI trial.

Abstract

Few data are available regarding the relation of left ventricular (LV) mechanical dyssynchrony to remodelling after acute myocardial infarction (MI) and stem cell therapy. We evaluated the 1-year time course of both LV mechanical dyssynchrony and remodelling in patients enrolled in the BONAMI trial, a randomized, multicenter controlled trial assessing cell therapy in patients with reperfused MI. Patients with acute MI and ejection fraction (EF) ≤ 45% were randomized to cell therapy or to control and underwent thallium single-photon emission computed tomography (SPECT), radionuclide angiography, and echocardiography at baseline, 3months, and 1year. Eighty-three patients with a comprehensive 1-year follow-up were included. LV dyssynchrony was assessed by the standard deviation (SD) of the LV phase histogram using radionuclide angiography. Remodelling was defined as a 20% increase in LV end-systolic volume index (LVESVI) at 1year. At baseline, LVEF, wall motion score index, and perfusion defect size were significantly impaired in the 43 patients (52%) with LV remodelling (all p < 0.001), without significant increase in LV mechanical dyssynchrony. During follow-up, there was a progressive increase in LV SD (p = 0.01). Baseline independent predictors of LV remodelling were perfusion SPECT defect size (p = 0.001), LVEF (p = 0.01) and a history of hypertension (p = 0.043). Bone marrow cell therapy did not affect the time-course of LV remodelling and dyssynchrony. LV remodelling 1year after reperfused MI is associated with progressive LV dyssynchrony and is related to baseline infarct size and ejection fraction, without impact of cell therapy on this process.