BACKGROUND: Cardiac contractility modulation (CCM) delivers nonexcitatory electrical signals to the heart during the absolute refractory period intended to improve contraction. METHODS: We tested CCM in 428 New York Heart Association class III or IV, narrow QRS heart failure patients with ejection fraction (EF) /= 25% and New York Heart Association class III symptoms) in which all parameters were improved by CCM. CONCLUSIONS: In the overall target population, CCM did not improve VAT (the primary end point) but did improve pVo and MLWHFQ. Cardiac contractility modulation did not have an adverse affect on hospitalizations or mortality within the prespecified boundaries. Further study is required to clarify the role of CCM as a treatment for medically refractory heart failure.
Tags: Anaerobic Threshold, analysis, Cardiac Resynchronization Therapy, contractility, contraction, Disease Progression, EF, female, heart, heart failure, Hospitalization, Humans, male, methods, Middle Aged, Minnesota, mortality, myocardial contraction, New York, patients, physiopathology, Prospective Studies, Research, Safety, Single-Blind Method, therapy, Vo