Borislav Dinov

Outcomes in Catheter Ablation of Ventricular Tachycardia in Dilated Nonischemic Cardiomyopathy Compared With Ischemic Cardiomyopathy Results From the Prospective Heart Centre of Leipzig VT (HELP-VT) Study

Background— Data on the outcomes of ventricular tachycardia (VT) ablation in nonischemic dilated cardiomyopathy (NIDCM) are insufficient. The Heart Center of Leipzig VT (HELP-VT) study was conducted prospectively to compare outcomes after radiofrequency catheter ablation of VT in patients with NIDCM compared with ischemic cardiomyopathy (ICM). Methods and Results— Two hundred twenty-seven patients, 63 with NIDCM and 164 with ICM, presenting with sustained VT were ablated with radiofrequency catheter ablation. Noninducibility of any clinical and nonclinical VT was achieved in 66.7% of NIDCM and in 77.4% of ICM patients. Ablation of the clinical VT only was achieved in 18.3% of ICM and in 22.2% of NIDCM patients. There was no statistically significant difference in short-term outcomes between the 2 groups. At the 1-year follow-up, VT-free survival in NIDCM was 40.5% compared with 57% in ICM. In univariate analysis, the hazard ratio for VT recurrence was significantly higher for NIDCM (1.62; 95% confidence interval, 1.12– 2.34; P=0.01). In both the ICM and NIDCM subgroups, procedure failure and incomplete procedural success were independent predictors of VT recurrence. Conclusions— Although the short-term success rates after VT ablation in NIDCM and ICM patients were similar, the long-term outcomes in NIDCM patients were significantly worse. Complete VT noninducibility at the end of the ablation is associated with beneficial long-term outcome in NIDCM. Pursuing compete elimination of all inducible VTs is desirable and may improve the long-term success in NIDCM.

Long-term follow-up after atrial fibrillation ablation in patients with impaired left ventricular systolic function: The importance of rhythm and rate control

BACKGROUND Atrial fibrillation (AF) ablation is increasingly used in patients with reduced left ventricular ejection fraction (LVEF), but long-term outcomes are still unknown. OBJECTIVE To assess the long-term effects of AF ablation in patients with systolic heart failure according to rhythm outcome. METHODS We included 69 patients with LVEF ≤40%, referred for circumferential pulmonary vein isolation with or without additional substrate modification to our institution in 2006-2010. Follow-up included 7-day Holter electrocardiography and echocardiography at baseline and at 6, 12, and 24 months after ablation. A matched control group (n = 69) after AF ablation without heart failure was used for comparison. RESULTS After 28 ± 11 months and 1.6 ± 0.7 ablation procedures, 45 (65%) patients were still in the stable sinus rhythm (SSR) group. LVEF increased from 33 ± 6% to 53 ± 11% (P < .001) in the SSR group and from 33 ± 5% to 38 ± 12% (P = .03) in patients with recurrences (atrial tachycardia/fibrillation group). While LVEF increase was similar in the 2 groups at 6 months (15 ± 12% vs 8 ± 11%; P = .2), further LVEF improvements were observed in the SSR group only. Adjustments for baseline characteristics revealed that the increase in LVEF at 6 months was associated with higher baseline heart rate and not with rhythm outcome. Heart rate did not change in either group after 6 months of follow-up. Complications and procedural data of the study group were similar to the control group. CONCLUSION In patients with heart failure undergoing AF ablation, there is an initial short-term LVEF improvement related to baseline heart rate. However, long-term LVEF improvement is associated with rhythm outcome.

Early Referral for Ablation of Scar-Related Ventricular Tachycardia Is Associated With Improved Acute and Long-Term Outcomes Results From the Heart Center of Leipzig Ventricular Tachycardia Registry

Background—The effects of time to referral for catheter ablation (CA) of scar-related ventricular tachycardia (VT) on acute success, VT recurrence, and cardiac mortality are unclear. Methods and Results—We investigated 300 patients after CA of sustained VT. CA was performed within 30 days after the first documented VT in 75 (25%) patients (group 1), between 1 month and 1 year in 84 (28%) patients (group 2), and >1 year after the first VT occurrence in 141 (47%) patients (group 3). The end points were noninducibility of any VT after CA (acute success), VT recurrence and cardiac mortality after 2 years. Acute success was achieved in 66 (88%) patients in group 1, 68 (81%) in group 2, and in 99 (70.2%) in group 3 (P=0.008). During the 2-year follow-up period, VT recurred in 28 (37.3%) patients in group 1, 52 (61.9%) patients in group 2, and 91 (64.5%) patients in group 3 (P<0.0001). Recurrence-free survival was higher in group 1, as compared with group 2 (hazard ratio [HR], 1.85; P=0.009) and group 3 (HR, 2.04; P=0.001). No survival difference was observed between groups 1 and 2 (HR, 0.85; P=0.68) and groups 1 and 3 (HR, 1.13; P=0.73). &bgr;-blocker therapy, VT of ischemic origin, and complete success were associated with VT-free survival. VT recurrence (HR, 1.91; P=0.037) predicted cardiac mortality. Conclusions—CA of scar-related VT performed within 30 days after the first documented VT was associated with improved acute and long-term success. VT recurrence, but not the early referral for CA, was associated with cardiovascular mortality.

Long‐Term Efficacy of Single Procedure Remote Magnetic Catheter Navigation for Ablation of Ischemic Ventricular Tachycardia: A Retrospective Study

Long‐Term Efficacy of Single Procedure Remote Magnetic Catheter Navigation.

Catheter Ablation of Ventricular Tachycardia and Mortality in Patients with Nonischemic Dilated Cardiomyopathy: Can Noninducibility after Ablation be a Predictor for Reduced Mortality?

Background—Data on outcomes after catheter ablation of ventricular tachycardia (VT) in patients with nonischemic dilated cardiomyopathy (NIDCM) are insufficient. We aimed to investigate the effects of successful catheter ablation of VT on cardiac mortality in patients with NIDCM. Methods and Results—One hundred two patients with NIDCM (86 men; mean age, 58.8±15.2 years; mean ejection fraction, 33.3±11.9%) underwent VT ablation. After catheter ablation, a programmed ventricular stimulation to test for success was performed. Complete VT noninducibility was achieved in 62 (61%) patients and partial success or failure in 32 (31%) patients. During 2 years of follow-up, VT recurrence was observed in 33 patients (53%) without inducible VTs and in 24 patients (75%) with inducible VT inducible (P=0.041). VT inducibility was associated with higher VT recurrence (adjusted hazard ratio, 1.84; 95% confidence interval, 1.08–3.13; P=0.025). The primary end point of all-cause mortality was reached in 9 patients (15%) with noninducible VTs versus 11 patients (34%) with inducible sustained VTs (P=0.026). VT inducibility was associated with all-cause mortality (adjusted hazard ratio, 2.73; 95% confidence interval, 1.003–7.43; P=0.049). Conclusions—In patients with NIDCM and recurrent sustained VTs, a complete ablation of all inducible VTs may be achieved in 60% of the cases. The complete noninducibility may be a preferable end point of ablation because it was associated with better long-term success. Importantly, if possible to achieve through ablation, a complete VT noninducibility was associated with reduction of the likelihood for all-cause mortality in patients with NIDCM.

Treatment with novel oral anticoagulants in a real-world cohort of patients undergoing cardiac rhythm device implantations

AIMS The safety and efficacy of novel oral anticoagulants in patients with atrial fibrillation undergoing pacemaker or implantable cardioverter-defibrillator interventions have not been clearly defined. Therefore, we compared the incidence of bleeding and thrombo-embolic complications following cardiac rhythm device (CRD) implantations under dabigatran vs. rivaroxaban in a real-world cohort. METHODS AND RESULTS We analysed 176 consecutive procedures performed in 93 patients treated peri-interventionally with dabigatran and 83 patients with rivaroxaban, respectively. Post-operative bleeding complications and thrombo-embolic events occurring within 30 days were compared. There were no significant differences in baseline characteristics between patients in the dabigatran and the rivaroxaban group. Most of the patients in both the groups received dual chamber or cardiac resynchronization devices (71 vs. 78%) as opposed to single-chamber systems (29 vs. 22%). In the dabigatran group, two (2%) bleeding complications (two pocket haematomas) were observed in comparison with four (5%, three pocket haematomas and one pericardial effusion) in the rivaroxaban group (P = 0.330). Three complications in the rivaroxaban group necessitated surgical intervention as opposed to none in the dabigatran group (P = 0.064). One case of a transient ischaemic attack occurred in the dabigatran group (P = 0.343). CONCLUSION Bleeding and thrombo-embolic complications in patients treated with dabigatran or rivaroxban are rare. Further and larger studies are warranted to define the optimal anticoagulation management in patients with a need for oral anticoagulation and CRD interventions.

Impact of Metabolic Syndrome on Left Atrial Electroanatomical Remodeling and Outcomes After Radiofrequency Ablation of Nonvalvular Atrial Fibrillation

Background—Recent studies reported worse outcomes after atrial fibrillation (AF) ablation in patients with metabolic syndrome (MetS). However, mechanisms of AF recurrence in MetS remain unclear. Method and Results—We performed pulmonary vein isolation and voltage mapping in 236 patients with AF (age 61±9.6 years; persistent AF 64%; MetS 54%). Left atrial (LA) low voltage areas were semiquantitatively estimated and presented as low voltage index. MetS was defined according to National Cholesterol Education Program Adult Treatment Panel III. Follow-up for AF recurrence ⩽12 months was performed. LA low voltage areas were observed in 46% of patients with MetS versus 8.2% patients without MetS ; P<0.0001. MetS was an independent predictor of LA low voltage areas: odds ratio, 11.64; 95% confidence interval, 4.381–30.903; P<0.0001. Observed AF recurrence at 12 months was 42.7% in MetS versus 36.1% in the non-MetS group (P=0.303). The presence of LA low voltage areas was a predictor of 12-month AF recurrence: odds ratio, 2.99; 95% confidence interval, 1.36–6.56; P=0.006. Probability of 12-month AF recurrence increased with 84.5% for every unit of low voltage Index. Conclusions—MetS was not associated with worse outcomes after radiofrequency catheter ablation of AF, but LA low voltage areas were more frequently observed in patients with MetS. The presence and extent of LA low voltage areas may influence the long-term outcomes after catheter ablation.

Prospective, multicenter validation of a clinical risk score for left atrial arrhythmogenic substrate based on voltage analysis: DR-FLASH score

BACKGROUND Left atrial (LA) low-voltage areas (LVAs) are frequently observed in patients with atrial fibrillation (AF) and may predict AF recurrence after catheter ablation. OBJECTIVE The aim of this study was to develop and validate a clinical tool to identify LVAs that are associated with AF recurrence after pulmonary vein isolation (PVI). METHODS In a cohort of 238 patients, voltage maps were created during LA procedures. LVAs were defined as areas with electrogram amplitudes <0.5 mV. On the basis of regression analysis, predictors of LA substrate were identified. These parameters were used to establish a dedicated risk score (DR-FLASH score, based on diabetes mellitus, renal dysfunction, persistent form of AF, LA diameter >45 mm, age >65 years, female sex, and hypertension). This risk score was then prospectively validated in a multicenter cohort of 180 patients. The association of the score with long-term recurrence of atrial arrhythmias after circumferential PVI was tested in a retrospective cohort of 484 patients. RESULTS The DR-FLASH score effectively identified LVA substrate (C statistic = 0.801, P < .001). In the prospective multicenter validation cohort, the predictive value of the DR-FLASH score was confirmed (C statistic = 0.767, P < .001). The probability for the presence of LA substrate increased by a factor of 2.2 (95% confidence interval [CI] 1.6-2.9, P < .001) with each point scored. Furthermore, the risk of AF recurrence after PVI increased by a factor of 1.3 (95% CI 1.1-1.5, P < .001) with every additional point and was almost 2 times higher in patients with a DR-FLASH score >3 (odds ratio 1.7, 95% CI 1.1-2.8, P = .026). CONCLUSION The DR-FLASH score may be useful to identify patients who may require extensive substrate modification instead of PVI alone.

Galectin-3 in patients with atrial fibrillation undergoing radiofrequency catheter ablation.

Background Galectin-3 (Gal-3) is an emerging biomarker in heart failure that is involved in fibrosis and inflammation. However, its potential value as a prognostic marker in atrial fibrillation (AF) is unknown. The aim of this study was to assess the impact of AF catheter ablation on Gal-3 and evaluate its prognostic impact for predicting rhythm outcome after catheter ablation. Methods Gal-3 was measured at baseline and after 6 months using specific ELISA. AF recurrences were defined as any atrial arrhythmia lasting longer than 30 sec within 6 months after ablation. Results In 105 AF patients (65% males, age 62±9 years, 52% paroxysmal AF) undergoing catheter ablation, Gal-3 was measured at baseline and after 6 months and compared with an AF-free control cohort (n=14, 50 % males, age 58±11 years). Gal-3 was higher in AF patients compared with AF-free controls (7.8±2.9 vs. 5.8±1.8, ng/mL, p=0.013). However, on multivariable analysis, BMI (p=0.007) but not AF (p=0.068) was associated with Gal-3. In the AF cohort, on univariable analysis higher Gal-3 levels were associated with female gender (p=0.028), higher BMI (p=0.005) and both CHADS2 (p=0.008) and CHA2DS2-VASC (p=0.016) scores, however, on multivariable analysis only BMI remained significantly associated with baseline Gal-3 (p=0.016). Gal-3 was similar 6 months after AF catheter ablation and was not associated with sinus rhythm maintenance. Conclusions Although galectin-3 levels are higher in AF patients, this is driven by cardiometabolic co-morbidities and not heart rhythm. Gal-3 is not useful for predicting rhythm outcome of catheter ablation.

Procedural Outcomes and Survival After Catheter Ablation of Ventricular Tachycardia in Relation to Electroanatomical Substrate in Patients With Nonischemic-Dilated Cardiomyopathy: The Role of Unipolar Voltage Mapping.

In patients with ischemic cardiomyopathy the size of bipolar low‐voltage areas (LVA) in electroanatomical maps (EAM) was associated with poorer outcomes after catheter ablation (CA) of ventricular tachycardia (VT). However, the effect of LVA size on the survival after VT ablation in patients with nonischemic dilated cardiomyopathy (NIDCM) has not been studied.