Cardiac Contractility Modulation in Patients With Chronic Heart Failure and the Various Forms of Atrial Fibrillation

Overview

Chronic heart failure (CHF) is a global pandemic which affects around 26 million people worldwide and develops in 10% of people over 70 years . According to the results of the EPOCHA-CHF study, CHF is detected in 7-10% of cases in the Russian Federation . Atrial fibrillation (AF) is the most common arrhythmia in patients with both preserved (HFpEF) and reduced ejection fraction (HFrEF) heart failure. The prognostic impact of AF on CHF is negative, including the significant increase in mortality and hospitalization. One of the common causes of decompensation of CHF is AF. The debut of AF in CHF is one of the markers of disease progression. Rapid development in interventional cardiology due to the invention of cardiac catheter technologies during the last decades provided a new option for non-pharmacological treatment of CHF. Nowadays the use of electrophysiological methods of treatment can significantly improve the prognosis of CHF. Pacemakers, cardiac resynchronization devices, and cardioverter defibrillators are the most commonly implanted devices in patients with CHF. In 2014, the European Society of Cardiology presented a report of the European Heart Rhythm Association on the use of new devices for CHF, including the Optimizer device for delivery of cardiac contractility modulation therapy (CCM) . It is worth noting that CCM is a new step in the CHF treatment. This device is of proven benefit to patients with symptomatic heart failure on optimal medical therapy who do not qualify for cardiac resynchronization therapy. Multiple studies of CCM show clinical improvement with this therapy, including metrics such as peak VO2, 6MW, and NYHA functional class. However, the vast majority of patients enrolled in these studies were patients in sinus rhythm. As the technology progressed and the need for the trial sensing led wanted, further experiences incorporated patients with AF. A new generation of devices (Optimizer Smart®), which does not require the implantation of an atrial electrode made it possible to implant CCM in patients with AF. The present trial demonstrates the results of a pilot study conducted in National Medical Research Center of Cardiology Ministry of Health of the Russian Federation which compares the efficacy of CCM in patients with AF and ischemic and non-ischemic CHF compared to patients who received only optimal drug therapy CHF

Background: Chronic heart failure (CHF) and atrial fibrillation (AF) often coexist and lead to severe decompensation of patients' lifestyle. Nowadays device therapy such as cardiac contractility modulation (CCM), which is used in addition to medical treatment, can significantly impact further prognosis and outcomes of patients with such comorbidities. Methods: In the National Medical Research Center of Cardiology we conducted a study dedicated to investigating the efficacy of CCM in patients with CHF and AF. 200 patients with Hf and AF were included in the study and were divided into two groups according to implantation of a heart contractility modulation device and optimal drug therapy. 100 patients were implanted with a CCM Optimizer device without an atrial lead, per the protocol specifications ( 1 group) and 100 patients ( 2 group) received only optimal drug therapy CHF The following studies were performed in the 200 patients with CHF and AF before implantation of the MCC device and after 2 and 6 и 12 months of follow-up: 12-channel ECG with an estimate of the width of the QRS complex, transthoracic EchoCG, Speckle-tracking EchoCG, Myocardial work, 6-minute walk test, determination of the level of Pro-natriuretic N-terminal peptide (NT-proBNP), Holter ECG, and a questionnaire based on the Minnesota quality of life questionnaire for patients with CHF (MHFLQ),Perfusion Single-Photon Emission Computed Tomography All patients received long-term optimal drug therapy for CHF before surgery.