The Predictive Value of Dobutamine Echo-stress in the Clinical Response to CCM Therapy in Advanced HF

-Introductory summary When no other therapeutic options are available, CCM can be a helpful complement to treating heart failure, improving quality of life, and prolonging survival. Still, the high cost and availability of implants in qualified centers limit their use.

Then, searching for indicators that maximize the benefit/risk ratio is appropriate. According to the study's proponents, the contractile reserve of the left ventricle assessed by stress echo to low-dose Dobutamine may be among the most promising indicators for this purpose.

Introduction Heart failure (H.F.) has a very poor prognosis in terms of mortality, quality of life, and functional capacity. It is one of the most important cardiovascular diseases in terms of global prevalence and healthcare costs. Despite appropriate medical care, many patients experience frequent hospitalizations and limitations in daily activities (1).

The prevalence of heart failure ranges between 1% and 3% in the general adult population in industrialized countries. It is expected to increase substantially due to the availability of better diagnostic tools and medical treatments that prolong life after diagnosis of HF (2).

The latest international guidelines on the management of reduced ejection fraction H.F. recommend a timely approach with the simultaneous introduction of the four main categories of drugs (ACE inhibitors or ARNIs, beta-blockers, mineralocorticoid receptor antagonists (MRAs), and SGLT2 inhibitors). If drug therapy alone is not sufficient or not well tolerated by the subject, or if there is a disorder in the conduction of the electrical impulse (in particular, a left bundle branch block), it is possible to associate it with electrical therapy, which consists of the implantation of biventricular cardiac devices (pacemakers or defibrillators) that resynchronize cardiac contraction (cardiac resynchronization therapy, CRT). These devices work in close synergy with anti-decompensation drugs to curb the progression of heart failure and, in some cases, restore normal cardiac contractility. Cardiac resynchronization therapy, combined with drug therapy, has been shown to improve survival and quality of life by reducing the symptoms of heart failure, increasing exercise capacity, and enabling subjects to resume many of their daily activities.

Cardiac Contractility Modulation (CCM) CRT is indicated for patients with a large QRS (\>130 ms and evidence of left bundle branch block)3; however, the percentage of individuals who do not respond to CRT varies between studies, usually between 25% and 33% (4). Randomized clinical trials have shown that Cardiac Contractility Modulation (CCM) is a treatment option5 for patients with symptomatic heart failure despite optimized medical therapy and not eligible for CRT. CCM therapy has also been evaluated in patients who have not responded to CRT (6) therapy.