Репозиторий Университета

© 2018 Limited Liability Company KlinMed Consulting. All Rights Reserved. The article covers the development of the problem of sudden cardiac death prevention with the implantable cardioverterdefibrillators from the moment of creation of these devices to our days. The current concept of primary prevention of sudden cardiac death, based on the severity of manifestation of heart failure and left ventricular dysfunction, is not effective enough. Its practical application is difficult because it requires mass application of implantable defibrillators, with low predictive accuracy of these criteria in terms of development of lifethreatening arrhythmias. The development of methods for visualizing the myocardium, allowing to assess the severity of myocardial fibrosis, as well as the possibilities of medical genetics, at the present stage, allows us to clarify indications for implantation of cardioverterdefibrillators and thereby significantly improve the concept of preventing sudden cardiac death with these instruments.

© 2018 GEOTAR Media. All rights reserved. Aim: to value the significance of various predictors of sudden cardiac death (SCD) and clarify the selection criteria for implantation of cardioverter-defibrillators in patients with cardiomyopathies [dilated (DCM), arrhythmogenic right ventricular (ARVC), left ventricular noncompaction (LVNC)]. Material and methods. 220 patients with DCM syndrome were observed, 151 men, average age 47.5±12.5 years [mean left ventricular end-diastolic dimension (LV EDD) 6.5 [6.0, 7.1] cm, LV EF 30.3±10.1%], 50 patients with ARVC (definite diagnosis in 26 patients, probable in 13, possible in 11), 20 men, average age 38.1±14.6 years and 108 patients with a definite diagnosis of LVNC, 63 men, average age 45.4±14.8 years [mean LV ejection fraction (LF EV) 38.4±14.4%, LV EDD 5.9±0.8 cm]. The average follow-up periods were 16 [6, 37], 13.5 [4, 34] and 14 [3, 5, 36.0] months accordingly. The decision to implant the ICD / CRT-D was taken individually. The endpoints of the study were overall mortality, SCD, death + transplantation, appropriate defibrillators shocks and the "shocks + SCD". Results. The overall mortality in DCM, ARVC, and LVNC was 19.1%, 14.0% and 14.8%. It was mainly determined by terminal heart failure; SCD was recorded in 2.7%, 4.0% and 2.8%. Cardioverter-defibrillators were implanted in 66 (30%) patients with DCM (37 ICD, 29 CRT-D, 93.9% as the primary prevention of SCD), in 13 (26%) patients with ARVC (only ICD, primary prevention in 32,1%) and in 33 (30,6%) patients with LVNC (24 ICD, 9 CRTD, primary prevention in 88,1%). The frequency of appropriate shocks was 18.2% (15.0% in the primary prevention group and 50.0% in the secondary group) in patients with DCM syndrome, 69.2% (33.3% and 80.0% %) in ARVC, and 27.2% in LVNC (22.2% and 50.0%). The primary (genetic) nature of DCM (RR 1.58, OR 10.93), stable VT (RR 18, OR 26.5), and unstable VT (RR 1.43), a low QRS voltage (RR 1.75, OR 1.98), absence of LV hypertrophy signs on the ECG (RR 1.37, OR 2.56) were identified as criteria for selection for the implantation of a defibrillators in patients with DCM syndrome. In the patients with ARVC, these were a stable VT/VF and syncope (RR 4.75, OR 19), male sex (RR 1.25, OR 2), the low QRS voltage (RR 2.2, OR 10.5), chronic heart failure (OR 2.4, OR 8.0), the size of RV 2.85 cm (RR 1.55, OR 3.5), LV EDD> 5.5 cm (RR 2.1, OR 16, 7). In patients with LVNC the criteria were a stable VT/ VF, the presence of myocarditis (RR 3.3, OR 6.3), more than 500 PVBs per day (RR 3.3, OR 4.9), the low QRS voltage (RR 1,1, ОR 1,1), the follow up more than one year (RR 1,5, ОR 1,8). EF is not a statistically significant predictor of appropriate defibrillators shocks. Conclusions. In patients with various cardiomyopathies, which are accompanied by a high risk of SCD, the implantation of a cardioverter-defibrillators is an effective method of preventing SCD, including primary prevention. Due to adequate use of cardioverter-defibrillators in patients with DCM, ARVC and LVNC implanted in view of conventional and additional indications established in the study, mortality is determined primarily not by SCD, but terminal heart failure. Isolated myocarditis as the cause of DCM syndrome is not accompanied by a high risk of SCD, but its adherence to genetic cardiomyopathy determines the high risk of SCD.

© 2018, Silicea-Poligraf. All rights reserved. Aim. To evaluate the exact efficacy of the implantable cardioverter-defibrillators (ICD) and combination devices (CRT-D), and to evaluate their influence on the rate of sudden death and overall mortality in patients with the dilation cardiomyopathy syndrome (DCMP), and to clarify the selection criteria for implantation. Material and methods. Totally, 220 DCMP patients investigated: 66 (30%) of them (mean age 48,5±12,8 y. o., 47 males) underwent implantation of ICD (n=37) and CRT-D (n=29), 154 (70%) patients were in comparison group (mean age 47,1±12,4 y. o., 104 males). In 60 patients (93,9%) the devices were implanted for primary prevention of sudden cardiac death (SCD). Follow-up lasted for 16 [6; 37] months. As primary endpoints, the following parameters were used: “death+transplantation”, mortality, SCD, “SCD+shock” and “death+transplantation+proper shocks of the defibrillators”. Results. Mortality in all DCMP patients was 19,1%, “death+transplantation” — 21,4%, SCD — 2,7%. There were no significant differences by these values in patients with both devices (19,7%; 22,7% and 1,5%), ICD (21,6%; 24,3% and 2,7%), CRT-D (17,2%; 20,7; and 0) and patients with no devices (18,8%; 20,8% and 3,2%). Significantly higher rates by “SCD+shocks” (18,2% v 3,2%, p<0,001) and “death+transplantation+shocks” (36,4% vs 20,8%, p<0,05) in patients with the implanted devices witness for real impact of the defibrillators in equality of overall mortality and SCD parameters. Among the patients with implanted devices, the genetic and mixed (genetic and inflammatory) nature of DCMP predominated (62,1 v 35,7%, p<0,001), there was significantly lower EF (26,3±9,2 v 30,7±10,3%, p<0,01), its end value (31,1±11,0 v 39,2±13,5%, p<0,01), significantly higher end diastolic size of the left ventricle (EDS, LV, 6,8±0,8 v 6,5±0,8 cm, p<0,05) and the grade of mitral regurgitation. In patients with the devices, rate of proper shocks was 18,2%. In isolated myocarditis there were no shocks (35,3±9,1% v 26,8±9,3%, p<0,05), EDS significantly lower (6,2±0,6 cm v 6,9±0,9 cm, p<0,01), ECG signs of LV hypertrophy were more rare (16,7% v 56,3%, p<0,05), but more commonly — the low voltage of QRS (33,3% v 10,6%, p=0,53); there were no differences in the rates of cardiotropic drugs prescription. Main predictors of the shocks were genetic origin of DCMP (isolated or with myocarditis, 25/75%, comparing with 20/33% in patients with no shocks, p<0,01, HR 1,58, OR 10,93, sensitivity 94,1%, negative predictive value 99,2%), and sustained (HR 18,0, sensitivity 98,1%) and non-sustained ventricular tachycardia (HR 1,43, sensitivity and negative predictive value 100%), decrease of QRS voltage and absence of the signs of LV hypertrophy on ECG (negative predictive value 92,8% and 95,6%). Conclusion. In DCMP patients, implanting of ICD/CRT-D was performed with acknowledged additional criteria (genetic or mixed DCMP etiology, lower EF and worse response to treatment); due to more effective ICD therapy, the values of mortality, “death+transplantation” and SCD were not higher than in less severe patients with no such devices. Proper shocks developed in patients with significantly higher EF. As an independent SCD risk factor and a criteria for patients selection to defibrillator implantation, genetic origin of DCMP should be used, especially if comorbid with myocarditis. As the predictors for benign outcome — absence of non-sustained ventricular tachycardia, lower QRS voltage, signs of LV hypertrophy on ECG. An algorithm proposed of DCMP patients selection for ICD treatment.