Cardiac contractility modulation: A treatment option for patients with refractory heart failure

Heart failure is the cardiovascular epidemic of the 21st century, with poor prognosis and quality of life despite optimized medical treatment. In the past two decades, only two new drugs have been added to therapeutic strategies for patients with symptomatic heart failure and even less progresses have been made on devices, with the implantable defibrillator indicated for patients with ejection fraction ≤35% and cardiac resynchronization therapy for those with QRS >130 ms and evidence of left bundle branch block. Nevertheless, only a third of patients meet these criteria and a high percentage of patients are non-responders in terms of improving symptoms. Nowadays, in patients with symptomatic heart failure with ejection fraction between 25% and 45% and QRS <130 ms, not eligible for cardiac resynchronization therapy, cardiac contractility modulation represents a concrete treatment option, having proved to be safe and effective in reducing hospitalizations for heart failure and improving symptoms, functional capacity and quality of life. The aim of this review is therefore to summarize the pathophysiological mechanisms, the current indications and the recent developments regarding the new applications of cardiac contractility modulation for patients with chronic heart failure.