[Predictive value of QRS complex duration in patients with chronic heart failure and atrial fibrillation: retrospective study].

AIM: To study of the features of the clinical course and prognosis in patients with chronic heart failure with low ejection fraction (HFrEF) and atrial fibrillation (AF) depending on the width of the QRS complex. MATERIALS AND METHODS: We studied the case histories of 514 patients (aged 60.213.84 years, 78% men) with HFrEF, hospitalized at the Chazov National Medical Research Center of Cardiology (Moscow) for the period from Jan 1, 2017 to Dec 31, 2018. Patients were divided into 2 groups depending on the duration of the QRS complex. RESULTS: Clinical and statistical retrospective analysis of the medical histories of patients with HFrEF, depending on the QRS duration, showed the predominance of patients with a QRS complex size of less than 130 ms (60.7%). In HFrEF, the expansion of the QRS complex is accompanied by an increase in the rate of readmission in patients with sinus rhythm (p=0.004). In patients with AF, the rehospitalization rate is significantly higher than in sinus rhythm and does not depend on the QRS duration (p=0.001). The incidence of unfavorable outcomes increases in connection with the addition of AF, which is most likely a more significant risk factor than QRS width. CONCLUSION: These results highlight that patients with AF and a narrow QRS complex have the same poor prognosis as those with a wide QRS complex and require the close attention of cardiologists.

[Dynamics of Holter electrocardiogram monitoring in patients with chronic heart failure and atrial fibrillation on the background of cardiac contractility modulation].

AIM: To evaluate the dynamics of cardiac arrhythmias on the background of cardiac contractility modulation (MCC) in patients with chronic heart failure (CHF) and various forms of atrial fibrillation (AF) on the basis of daily electrocardiogram (ECG) monitoring. MATERIALS AND METHODS: In 100 patients with CHF and AF, the following studies were performed before implantation of the MCC device and after 12 months of follow-up: 12-channel ECG with an estimate of the width of the QRS complex, transthoracic echocardiography (EchoCG), and Holter ECG monitoring. All patients received long-term optimal drug therapy for CHF before surgery. RESULTS: The results obtained indicate that there is no effect of MCC on the development and progression of ventricular arrhythmias in patients with CHF and AF during the year of follow-up, both extrasystole and tachyarrhythmias, regardless of the etiology and LVEF (less than 35% or more than 35%), and a decrease in the frequency of AF paroxysms in patients with CHF during treatment. These results are due to the reverse remodeling of the LV myocardium under the influence of the MCC device. CONCLUSION: The use of MСС in patients with CHF and AF is a safe method of therapy that does not induce cardiac arrhythmias, including ventricular extrasystole. Large-scale comparative studies are required to evaluate these results.