Purposes: To determine if 123MIBG (meta-iodo-benzyl-guanidine) cardiac scintigraphy can be used as predictor for CRT response.
Patients: We studied 126 patients, 66.7% male, mean age 69.4+12, 60% non ischemic, basal Left Ventricular ejection fraction 26.3±7%.
Methodology: Prospective one-centre study including consecutive HF pts submitted to CRT who performed echocardiography and planar cardiac scintigraphy with 123MIBG evaluation before cardiac resynchronizer implantation. Cardiac autonomic function was evaluated by the early and late heart-mediastinum ratio (HMRe and HMRl). Left ventricular systolic function was measured by left ventricular ejection fraction (LVEF), left ventricular systolic and diastolic volumes (LVES and LVED) and left ventricular mass (LV mass). CRT response was defined by LVEF increase at least 10% (relative value) after cardiac resynchronizer implant .
LVTD and LV mass were greater in HMRe and HMRl <1.5 (table 1).
HMRe + HMRl >3 was associated to CRT response (table2).
More severe cardiac autonomic dysfunction was present in heart failure patients referred to CRT with greater baseline left ventricular diastolic volume and mass. 123MIBG scintigraphic HMRe and HMRl added values superior to 3 was significantly associated to CRT response.