Sascha Rolf

Tailored Atrial Substrate Modification Based On Low-Voltage Areas in Catheter Ablation of Atrial Fibrillation

Background—Reduced electrogram amplitude has been shown to correlate with diseased myocardium. We describe a novel individualized approach for catheter ablation of atrial fibrillation (AF) based on low-voltage areas (LVAs) in the left atrium (LA). We sought to assess (1) the incidence of LVAs in patients undergoing AF catheter ablation, (2) the distribution of LVAs within the LA, and (3) the effect of an individualized ablation strategy on long-term rhythm outcomes. Methods and Results—In 178 patients with paroxysmal or persistent AF, LA voltage maps were created during sinus rhythm after circumferential pulmonary vein isolation. Subsequent substrate modification was confined to the presence of LVA (<0.5 mV) and inducible regular atrial tachycardias. LVAs were identified in 35% and 10% of patients with persistent and paroxysmal AF, respectively. The LA roof and the anterior, septal, and posterior wall LA were most often affected. The 12-month atrial tachycardias/AF-free survival was 62% for patients without LVAs and 70% for patients with LVAs and tailored substrate modification (P=0.3). Success rate in a comparison group of 26 LVA patients without further substrate modification was 27%. Conclusions—LVAs can be found at preferred sites in 10% of patients with paroxysmal AF and in 35% of patients with persistent AF. This is the first clinical report describing a consistent voltage-based approach for substrate modification in addition to circumferential pulmonary vein isolation irrespective of AF type. Application of this limited individualized approach may have the potential to compensate for the impaired 12-month outcome of patients with endocardial structural defects.

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.

Comparison of CHADS2, R2CHADS2 and CHA2DS2-VASc Scores for the Prediction of Rhythm Outcomes after Catheter Ablation of Atrial Fibrillation: The Leipzig Heart Center AF Ablation Registry

Background—Recurrences of atrial fibrillation (AF) occur in up to 30% within 1 year after catheter ablation. This study evaluated the value of CHADS2, R2CHADS2, and CHA2DS2-VASc scores for the prediction of rhythm outcomes after AF catheter ablation. Methods and Results—Using the Leipzig Heart Center AF Ablation Registry, we documented rhythm outcomes within the first 12 months in 2069 patients (67% men; 60±10 years; 35% persistent AF) undergoing AF catheter ablation. AF recurrences were defined as any atrial arrhythmia occurring within the first week (early recurrences, ERAF) and between 3 and 12 months (late recurrences, LRAF) after ablation. ERAF and LRAF occurred in 36% and 33%, respectively. On multivariable analysis, R2CHADS2 (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.02–1.21; P=0.016) and CHA2DS2-VASc (OR, 1.09; 95% CI, 1.017–1.17; P=0.015) scores as well as persistent AF and left atrial diameter were significant predictors for ERAF. Similarly, the same clinical variables remained significant predictors for LRAF even after adjustment for ERAF, which was the strongest predictor for LRAF (HR, 3.12; 95% CI, 2.62–3.71; P<0.001). However, using receiver operating characteristic curve analyses, both scores demonstrated relatively low predictive value for ERAF (area under the curve [AUC], 0.536 [0.510–0.563]; P=0.007; and AUC, 0.547 [0.521–0.573]; P<0.001 for R2CHADS2 and CHA2DS2-VASc, respectively) and LRAF (AUC, 0.548 [0.518–0.578]; P=0.002; and AUC, 0.550 [0.520–0.580]; P=0.001). Conclusions—R2CHADS2 and CHA2DS2-VASc were associated with rhythm outcomes after catheter ablation. However, AF type, left atrial diameter, and especially ERAF are also significant predictors for LRAF that should be included into new clinical scores for the prediction of rhythm outcomes after catheter ablation.

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

BACKGROUNDnAtrial fibrillation (AF) ablation is increasingly used in patients with reduced left ventricular ejection fraction (LVEF), but long-term outcomes are still unknown.nnnOBJECTIVEnTo assess the long-term effects of AF ablation in patients with systolic heart failure according to rhythm outcome.nnnMETHODSnWe 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.nnnRESULTSnAfter 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.nnnCONCLUSIONnIn 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.

Renal Dysfunction, Stroke Risk Scores (CHADS2, CHA2DS2-VASc and R2CHADS2) and the Risk of Thromboembolic Events after Catheter Ablation of Atrial Fibrillation: The Leipzig Heart Center AF Ablation Registry

Background— There are limited data on the predictive value of stroke risk scores for thromboembolic events (TEs) after catheter ablation of atrial fibrillation (AF). Our objectives were to report the incidence of TEs after AF ablation in a large contemporary AF ablation cohort and to investigate the impact of renal dysfunction and the value of stroke risk stratification scores (CHADS2, CHA2DS2-VASc, and R2CHADS2) for predicting TE after AF ablation. Methods and Results— Using the Leipzig Heart Center AF Ablation Registry, we documented TEs in patients undergoing radiofrequency AF catheter ablation. TE was defined as stroke, transient ischemic attack, or systemic embolism. Study population (N=2069; 66% men; 60±10 years; 62% paroxysmal AF; mean CHADS2, 1.2±0.9; CHA2DS2-VASc, 2.1±1.4; and R2CHADS2, 1.3±1.1) were followed up for a median 18 (Q1–Q3, 12–29) months (ie, 3078 patient-years). Overall, 31 TEs occurred, with 16 events within 30 days of ablation and 15 TEs (0.72%) during the follow-up period. On multivariate analysis, CHADS2 (P<0.001), R2CHADS2 (P<0.001), and CHA2DS2-VASc (P=0.003) scores were independent predictors of TEs during follow-up, and AF recurrence conferred a nonsignificant trend for increased TE risk (P=0.071–0.094). The CHA2DS2-VASc score further differentiated TE risk in patients with CHADS2 and R2CHADS2 0 to 1 (0.13% if CHA2DS2-VASc was 0–1 and 0.71% if CHA2DS2-VASc was >2) and had the best predictive value in patients with AF recurrences (c-index 0.894, P=0.022 versus CHADS2, P=0.031 versus R2CHADS2). Conclusions— CHADS2, CHA2DS2-VASc, and R2CHADS2 scores were associated with TE risk. The CHA2DS2-VASc score differentiated TE risk in the low-risk strata based on CHADS2 and R2CHADS2 scores and may be superior in the subgroup with AF recurrences.

The APPLE score: a novel and simple score for the prediction of rhythm outcomes after catheter ablation of atrial fibrillation

BackgroundRecurrent atrial fibrillation (AF) occurs in up to 50xa0% of patients within 1xa0year after catheter ablation, and a clinical risk score to predict recurrence remains a critical unmet need. The aim of this study was to (1) develop a simple score for the prediction of rhythm outcome following catheter ablation; (2) compare it with the CHADS2 and CHA2DS2-VASc scores, and (3) validate it in an external cohort.MethodsRhythm outcome between 3 and 12xa0months after AF catheter ablation were documented. The APPLE score [one point for age >65xa0years, persistent AF, impaired eGFR (<60xa0ml/min/1.73xa0m2), LA diameter ≥43xa0mm, EFxa0<xa050xa0%] was associated with AF recurrence and was validated in an external cohort in 261 patients with comparable ablation and follow-up.ResultsIn 1145 patients (60xa0±xa010xa0years, 65xa0% male, 62xa0% paroxysmal AF) the APPLE score showed better prediction of AF recurrences (AUC 0.634, 95xa0% CI 0.600–0.668, pxa0<xa00.001) than CHADS2 (AUC 0.538) and CHA2DS2-VASc (AUC 0.542). Compared to patients with an APPLE score of 0, the odds ratio for AF recurrences was 1.73, 2.79 and 4.70 for APPLE scores 1, 2, or ≥3, respectively (all pxa0<xa00.05). In the external validation cohort, the APPLE score showed similar results (AUC 0.624, 95xa0% CI 0.562–0.687, pxa0<xa00.001).ConclusionsThe novel APPLE score is superior to the CHADS2 and CHA2DS2-VASc scores for prediction of rhythm outcome after catheter ablation. It holds promise as a useful tool to identify patients with low, intermediate, and high risk for AF recurrence.

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.

Ablation of atrial fibrillation using novel 4-dimensional catheter tracking within autoregistered left atrial angiograms.

Background— We describe a novel fluoroscopy coregistered, 4-dimensional catheter tracking technology (MediGuide Technology [MGT]) used for treatment of patients with atrial fibrillation. The aim of the study was to investigate (1) the feasibility of nonfluoroscopic catheter manipulation within dynamic left atrial chamber models; (2) the integration of the technology into an established electroanatomical mapping system; and (3) potential clinical impact. Methods and Results— Forty-nine patients received atrial fibrillation ablation using MGT-enabled NavX-EnSite. Matched patients ablated with a conventional NavX-EnSite system served as a control group. MGT was used for the deployment of diagnostic catheters within preacquired cine loops, for nonfluoroscopic chamber mapping within dynamic angiograms, and for 4-dimensional tagging of anatomical landmarks. Integration with the electroanatomical mapping system allowed correction of field distortions and a reference tool to detect and correct map shifts. Catheter ablation was done without MGT because the ablation catheter was not MGT enabled. MGT worked safely and stably in all 49 patients. Catheter deployment within the preacquired cine loops was successfully performed in 45 of 49 (92%) patients. Catheter tracking within dynamic left atrial angiograms allowed nearly nonfluoroscopic creation of NavX-EnSite geometries with subsequent computed tomography model registration in all 49 patients. Overall, MGT significantly reduced total procedural fluoroscopy time (median [quartiles]) from 31 minutes (25, 43 minutes) to 16 minutes (10, 23 minutes) and irradiation dose from 14 453±7403 to 7363±5827 cGy*cm2 (mean±SD), respectively (P<0.001). Conclusions— MGT is a tracking technology that allows 4-dimensional visualization of dedicated catheters within moving chamber models. Integration of the MGT with an established electroanatomical mapping system provided algorithms to facilitate mapping in the electroanatomical mapping system environment. As a first measurable clinical impact, MGT was able to reduce fluoroscopy exposure by nearly 50%.

Catheter ablation of atrial fibrillation supported by novel nonfluoroscopic 4D navigation technology

BACKGROUNDnThe MediGuide technology (MGT) represents a novel sensor-based electromagnetic 4-dimensional (4D) navigation system allowing real-time catheter tracking in the environment of prerecorded X-ray loops.nnnOBJECTIVEnTo report on our clinical experience in atrial fibrillation (AF) ablation with recently available MGT-enabled ablation catheters.nnnMETHODSnThe MGT was used in addition to a conventional 3D mapping system in 80 patients with AF (age 61 ± 10 years; 47 men; 40 with persistent AF), who underwent circumferential pulmonary vein isolation and voltage mapping with and without substrate modification. Short native right anterior oblique/left anterior oblique loops were used as background movies for the nonfluoroscopic placement of sensor-equipped diagnostic catheters into the coronary sinus and the right ventricle. After single transseptal puncture, selective angiograms of the pulmonary veins were used as background movies for near nonfluoroscopic left atrial reconstruction. Computed tomography registration as well as mapping/ablation was performed by using the new open-irrigated MGT-enabled ablation catheter.nnnRESULTSnMGT application was not associated with a change in established workflow. Large parts of the procedure (mean entire duration 167 ± 47 minutes) could be done without additional fluoroscopy, whereas median residual fluoroscopy duration of 4.6 (interquartile range: 2.9, 7.1) minutes was mainly used for the acquisition of background loops, transseptal puncture, occasional verification of transseptal sheath position, and manipulation of the circular mapping catheter. Three (4%) minor complications occurred.nnnCONCLUSIONSnThe MGT integrates easily into the workflow of standard AF ablation and allows for high-quality nonfluoroscopic 4D catheter tracking. This results in low radiation exposure for patients and staff without complicating the workflow of the procedure.