Left ventricular myocardial cellular perfusion against the background of cardiac contractility modulation in patients with heart failure and atrial fibrillation

Aim. To assess the effect of cardiac contractility modulation (CCM) in patients with heart failure (HF) and atrial fibrillation (AF) on left ventricular (LV) myocardial cellular perfusion using perfusion single photon emission computed tomography (SPECT).Material and methods. 99mTc-MIBI SPECT gated myocardial perfusion imaging was performed in 60 patients with HF and AF before implantation of CCM device and after 6-months follow-up. All patients received long-term optimal medication therapy for HF. Results. The results obtained indicate a significant positive effect of CCM use in patients with HF and AF on LV ejection fraction (increase from 22 [18;30] to 25,5 [19;38] (p=0,002)), LV volume (decrease in LV end-systolic volume from 187 [114;238] to 154 [100;201] (p=0,001), end-diastolic volume from 229 [174;290] to 209 [159;259] (p=0,007)), as well as myocardial perfusion values. There is a favorable myocardial perfusion dynamics, which was more pronounced in nonischemic HF: increase in SRS from 6 [5;9] to 8,0 [6;11] after 6 months (p=0,01)). The extent of impaired perfusion significantly decreases from 12 [9;17] to 9 [6;16] (p=0,04). An indicator reflecting the total impairment of LV myocardial perfusion significantly decreases: total perfusion deficit decreased from 10 [8;14] to 7 [6;14] after 6 months (p=0,02), compared with ischemia-related HF.Conclusion. Perfusion SPECT makes it possible to assess the myocardial cellular perfusion during CCM therapy in patients with HF of various origin and AF. CCM therapy improves myocardial contractility and perfusion in patients with HF and AF

Safety and Tolerability of Implanted Subcutaneous Cardioverter-Defibrillator Systems

Aim. To study the safety and tolerability of the subcutaneous implantable cardioverter defibrillator (S-ICD) after implantation.Material and methods. The results of 33 patients with implanted S-ICD 6 months follow-up. The criteria for inclusion in the observational study were: age over 18 years, indications for primary or secondary prevention of sudden cardiac death. The exclusion criteria were indications for implantation of transvenous ICD (patients with sustained monomorphic ventricular tachycardia, the need for anti-bradycardia or resynchronization therapy), as well as patients with a QRS complex of more than 130 msec. All patients underwent a standard preoperative examination (routine blood tests, chest X-ray, transthoracic echocardiography), quality-of-life questionnaires and transesophageal echocardiography. At follow-up, patients were examined after 6 months after implantation, the device was interrogated and a quality-of-life questionnaire was completed. All episodes of shock therapy and complications were documented.Results. Male patients predominated (84%), with a mean age of 57 [43;62] years. Left ventricular ejection fraction was 30% [26;34]. The mean QRS duration was 100 [94;108] msec. According to the of 24-hour Holter ECG monitoring, episodes of unstable VT were recorded in 42.4% of patients. The most common indications for S-ICD implantation were dilated (33%) and ischemic cardiomyopathy (42%). Primary prevention was indicated in 97% of patients. At the end of the implantation of the S-ICD, the patients underwent a defibrillation test and device configuration. In 63.6% of cases, during automatic tuning, the device selected the primary perception vector. In 27.2% of patients, optimal recognition of the subcutaneous signal was observed in the secondary vector, and in 9.2% of patients, the alternative vector was favorable. All patients underwent two-zone programming. The conditional shock zone was programmed at an average rate of 192 beats/min (range 180-210 beats/min) and the shock zone was programmed at an average rate of 222 beats/min (range 220-240 beats/min). Perioperative complications occurred in two patients. During the follow-up period, no shocks were recorded in 27 patients. Adequate shocks for 6 months were recorded in two patients. During 6 months of observation, one lethal outcome was noted due to complications of viral pneumonia. During the observation period, there were no rehospitalizations for cardiovascular diseases.Conclusion. The use of S-ICD, even in patients with structural myocardial disease who do not require antibradycardia pacing, is effective in preventing SCD. The number of inadequate discharges and the number of complications in clinical practice is comparable to the data of multicenter studies. S-ICD implantation was not accompanied by a decrease in quality of life. Careful selection of candidates, along with state-of-the-art device programming, is an important parameter for the selection and success of S-ICD application

Possibilities of Evaluating the Dynamics of Left Ventricular Perfusion and Contractility in Patients with Chronic Heart Failure after Implantation of a Heart Contractility Modulator Using Perfusion Single-Photon Emission Computed Tomography

Perfusion scintigraphy and single-photon emission tomography of the myocardium are promising methods for complex assessment of the state of the left ventricle myocardium in patients with chronic heart failure. These methods of nuclear cardiology can be performed in patients with reduced renal function, as well as the presence of implanted devices such as implantable cardioverters-defibrillators, resynchronizing devices and cardiac modulating therapy, which is their undeniable advantage. The reproducibility of the method is ensured bu fully automated calculation of parameters of myocardial perfusion and contractility. To date, there are no data in the literature on the use of nuclear cardiology methods as an imaging technique in patients with cardiac contractility modulation devises. This paper describes the current possibilities and prospects of nuclear medicine methods in patients with chronic heart failure after implantation of a heart contractility modulator