[Efficacy and Safety of Nonfluoroscopic Approach During Catheter Ablation of Ventricular Tachycardias].

Aim      To evaluate a possibility of using radiofrequency catheter ablation guided by intracardiac echocardiography (ICE), its efficacy and safety for treatment of ventricular tachycardia (VT) of various etiology.Material and methods  Catheter intervention was performed for 20 enrolled patients with symptomatic VT. Ablation procedures were guided by a 3D electroanatomical mapping system and ICE.Results Mean duration of the procedure was 201.2±62.5 min. The procedure was successful (non-inducibility of VT) in 100% of cases. None of the patients had postoperative complications.Conclusion      Ablation of VT arrhythmogenic substrate guided by 3D electroanatomical navigational mapping and ICE without X-ray is feasible and safe.

[Possibilities of modern biomarkers for assessing the risk of developing ventricular tachyarrhythmias and sudden cardiac death in patients with chronic heart failure].

Current biomarkers allow diagnosing a wide array of pathological processes and evaluating effects of therapies and prognosis for cardiological patients. This review focuses on a possibility of using N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble suppressor of tumorigenicity 2 (sST2), galectin-3, and other biomarkers in patients with chronic heart failure for evaluating the risk of life-threatening ventricular tachyarrhythmias and sudden cardiac death.

New ECG criteria for differential diagnosis of wide QRS complex tachycardias with right bundle branch block pattern.

AIM: To evaluate standard 12-lead ECG indices for the differential diagnosis of wide QRS tachycardias with right bundle branch block (RBBB) pattern. MATERIALS AND METHODS: Study analyses the 244 ECG indices in 111 patients (79 males and 32 females, age 53±17 years) with RBBB tachycardias, who underwent electrophysiological studies. First step includes retrospective analysis of QRS characteristics in 20 patients with ventricular tachycardias (VT), 24 pts with aberrant supraventricular tachycardias (SVT+RBBB) and 14 pts with antidromic SVTs (WPW). ROC- and multifactorial analyses were performed to develop diagnostic ECG algorithms. The prognostic accuracy of the algorithms was subsequently evaluated on a prospective group of patients with RBBB tachycardias (n=53). RESULTS: ECG criteria of RBBB VTs were: 1) the presence Q-wave in lead II, 2) the duration interval R(peak)-S(end) >100 ms in lead V5. ECG criteria for antidromic SVTs with RBBB were: 1) the duration of the R wave in lead I ≥80 ms, 2) the absence of split (M-sharp) R-waves in lead V2, 3) the absence notch in ascending S wave in lead aVL. The accuracy of the algorhythm for diagnostic of VTs with RBBB was 83% (sensitivity 100%, specificity 73%). The accuracy of the algorhythm for diagnostic of antidromic SVTs with RBBB was 91% (sensitivity 85%, specificity 96%). CONCLUSION: The proposed algorithms are based on new ECG criteria for the differential diagnosis of wide QRS complexes tachycardias with RBBB pattern, unlike the previous algorithms.

Characteristic of fibrotic myocardial lesions associated with life-threatening ventricular tachyarrhythmias in patients with ischemic and non-ischemic cardiomyopathies.

AIM: To identify the features of myocardial scar and fibrosis associated with the occurrence of malignant ventricular tachyarrhythmias (VTs) in high-risk patients with ischemic (ICMP) and non-ischemic cardiomyopathy (NICMP). MATERIALS AND METHODS: This prospective study included 50 patients (41 men, 9 women), age = 60 ± 13 years, 30 patients of them with ICMP and 20 patients with NICMP, who underwent echocardiography (Echo) and contrast magnetic resonance imaging (MRI) of the heart followed by implantation of cardioverter-defibrillators (ICD) or resynchronizing devices with defibrillator (CPTD) to prevent sudden cardiac death. RESULTS: Sustained VTs were reported in 20/30 (67%) patients with ICMP and in 5/20 (25%) patients with NICMP on follow-up [26 (22-37) months]. Successive univariate and ROC-analyses of Echo and MRI-indices between patients with and without recurrence of VTs found different results for ICMP and NICMP patients groups. In ICMP patients the VTs were associated with wide transmural fibrosis on contrast MRI that covered 3 or more segments of left ventricular. These segments were preferably localized in the middle parts of the inferior and inferolateral segments of the left ventricle. The independent predictors of VTs in NICMP patients were non-transmural fibrosis at 4.5% of the left ventricular mass by contrast MRI as well as low left ventricular ejection fraction (less than 26%) by Echo. CONCLUSION: To determine the indications for implantation of the ICD and CRTD for primary prevention of sudden cardiac death, it is advisable to take into account not only the value of ejection fraction of left ventricular, but also the features of the fibrosis of the left ventricle by contrast MRI of the heart.

[Ventricular Tachycardia as a First Manifestation of Myotonic Dystrophy].

We report a case of bundle-branch reentrant ventricular tachycardia as a first and severe manifestation of myotonic dystrophy. Progressive cardiac conduction disturbances and cardiac arrhythmias are well-known features of myotonic dystrophy, although they are commonly found in late stage of disease in patients with established diagnosis. We review clinical manifestations, diagnostics, management, and prognostic value of cardiac involvement in myotonic dystrophy.

[Electrophysiological effects and antiarrhythmic activity of novel domestic class III antiarrhythmogenic drug niferidil administered in patients with paroxismal supraventricular tachycardia].

Intracardiac electrophysiological effects and antiarrhythmic activity of novel domestic class III antiarrhythmogenic drug niferidil has been studied in a group of 25 patients with paroxismal supraventricular tachycardia (PSVT) diagnosis. The drug was administered in a dose of 20 mg/kg (i.v.). Niferidil injections increased the refractory periods in both right and left atrium (by 22 and 20%, respectively, p < 0.001), right ventricle (12%, p < 0.01), and the His-Purkinje system (34%, p < 0.001) and improved additional anterograde and retrograde conduction (by 22 and 31%, respectively, p < 0.001), while not influencing the conduction via excitable cardiac tissues. Elongation of the QTc interval (22%, p <0.05) in one case was accompanied by an arrythmogenic effect (induction of short-term polymorphous ventricular tachycardia of the "torsade de pointes" type. Niferidil arrested PSVT in 78% cases and prevented PSVT development in response to endocardial stimulation in 86% of patients.

[Prediction of results of antiarrhythmic drug therapy in patients with malignant ventricular tachyarrhythmias, based on the prognostic value of left ventricular contractility parameters].

In 44 patients (3 women and 41 men, mean age 54 +/- 11 years) with malignant ventricular tachyarrhythmias (MVT) we assessed dependence of results of testing of antiarrhythmic drugs and efficacy of their long term use for prevention of recurrences of MVT on topography of derangement of local left ventricular (LV) contractility. Regional LV contractility was assessed with transthoracic echocardiography and radionuclide ventriculography (RNV). Testing of antiarrhythmic drugs was performed under control of repetitive intracardiac electrophysiological studies. Duration of follow-up was 28 (13 - 61) months. According to ROC-analysis most precise markers of positive results of drug testing were values of local ejection fraction (EF) in apical LV segment (10th segment on RNV) above 55%. Signs predisposing to absence of MVT recurrences during long term use of antiarrhythmic drugs were lack of mitral regurgitation (above I degree) according to echocardiography data, values of local EF in segment of lateral LV wall (4th segment on RNV) exceeding 42%, or value of LV end diastolic volume less than 365 ml according to RNV data. Parameters of local LV contractility are most precise markers of results of the use of antiarrhythmic drugs in patients with MVT, their diagnostic value is hair than that of global LVEF. Efficacy of antiarrhythmic drugs at electrophysiologic testing and long term follow-up are associated with different parameters of local LV contractility.