Sandeep R. Gangireddy

Feasibility and Safety of Uninterrupted Rivaroxaban for Periprocedural Anticoagulation in Patients Undergoing Radiofrequency Ablation for Atrial Fibrillation

OBJECTIVES The purpose of this study was to evaluate the feasibility and safety of uninterrupted rivaroxaban therapy during atrial fibrillation (AF) ablation. BACKGROUND Optimal periprocedural anticoagulation strategy is essential for minimizing bleeding and thromboembolic complications during and after AF ablation. The safety and efficacy of uninterrupted rivaroxaban therapy as a periprocedural anticoagulant for AF ablation are unknown. METHODS We performed a multicenter, observational, prospective study of a registry of patients undergoing AF ablation in 8 centers in North America. Patients taking uninterrupted periprocedural rivaroxaban were matched by age, sex, and type of AF with an equal number of patients taking uninterrupted warfarin therapy who were undergoing AF ablation during the same period. RESULTS A total of 642 patients were included in the study, with 321 in each group. Mean age was 63 ± 10 years, with 442 (69%) males and 328 (51%) patients with paroxysmal AF equally distributed between the 2 groups. Patients in the warfarin group had a slightly higher mean HAS- BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol concomitantly) score (1.70 ± 1.0 vs. 1.47 ± 0.9, respectively; p = 0.032). Bleeding and embolic complications occurred in 47 (7.3%) and 2 (0.3%) patients (both had transient ischemic attacks) respectively. There were no differences in the number of major bleeding complications (5 [1.6%] vs. 7 [1.9%], respectively; p = 0.772), minor bleeding complications (16 [5.0%] vs. 19 [5.9%], respectively; p = 0.602), or embolic complications (1 [0.3%] vs. 1 [0.3%], respectively; p = 1.0) between the rivaroxaban and warfarin groups in the first 30 days. CONCLUSIONS Uninterrupted rivaroxaban therapy appears to be as safe and efficacious in preventing bleeding and thromboembolic events in patients undergoing AF ablation as uninterrupted warfarin therapy.

Percutaneous left atrial appendage closure for stroke prevention in patients with atrial fibrillation: an assessment of net clinical benefit.

AIMS The PROTECT-AF (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients with Atrial Fibrillation) trial found left atrial appendage (LAA) closure an alternative to anticoagulation in selected patients with non-valvular atrial fibrillation (AF). We aim to estimate the net clinical benefit (NCB) of percutaneous LAA closure. METHODS AND RESULTS Post hoc analysis of outcomes among 707 adults with AF in the PROTECT-AF trial and 566 in the Continued Access (CAP) registry undergoing LAA closure with the Watchman device compared with sustained anticoagulation. Outcomes were ischaemic stroke, intracranial haemorrhage, major bleeding, pericardial effusion, and death, weighted to reflect the relative impact in terms of death and disability. Net clinical benefit was calculated as the sum of annualized rates of these outcomes after intervention minus rates on warfarin. The NCB of LAA closure during 1623 person-years follow-up in the trial was 1.73%/year (95% CI: -0.54 to 4.39%/year) and during 741 patient-years in the registry was 4.97%/year (95% CI: 3.07-7.15%/year). Among patients with a history of ischaemic stroke, the NCB was greater in the registry (8.68%/year, CI: 2.82-14.92%/year) than the trial (4.30%/year, CI -2.07 to 11.25%/year). In the registry, the NCB of LAA closure increased from 2.22%/year (CI: 0.27-6.01%/year) in patients with CHADS(2) scores = 1 to 6.12%/year (CI: 3.19-8.92%/year) in those with scores ≥2. CONCLUSION Combining rates of thrombo-embolism, intracranial haemorrhage, major adverse events, and death allows objective comparison of the benefit and risk of device therapy vs. anticoagulation in patients with AF. The NCB of LAA closure is greatest for patients at a higher risk of stroke.

Multicenter study on acute and long-term safety and efficacy of percutaneous left atrial appendage closure using an epicardial suture snaring device

BACKGROUND Pericardial suture ligation of the left atrial appendage (LAA) may be an alternative to endoluminal devices for stroke prevention in patients with atrial fibrillation, but multicenter safety and efficacy data in high-risk patients with contraindications to oral anticoagulation are lacking. OBJECTIVE The purpose of this study was to report the outcomes of consecutive cases of pericardial suture ligation of the LAA in high-risk patients performed at 4 centers. METHODS The cohort included 41 consecutive patients who underwent LAA closure with the LARIAT system. Epicardial and transeptal access was obtained, and the epicardial snare was advanced over an endo-epicardial magnetic-tipped guidewire to close the LAA. Transesophageal echocardiography was used to confirm LAA exclusion. RESULTS Mean age was 75 ± 10 years, mean CHADS2 score was 3.0 ± 1.3, and mean HAS-BLED score was 4.4 ± 1.4. These patients accumulated 24.6 person-years of follow-up. Acute LAA closure was achieved in 38 patients (93%). Transesophageal echocardiography or computerized tomographic angiography performed up to 3.3 ± 0.8 months after the procedure demonstrated LAA leakage in 24% of patients. One patient (2%) had a transient ischemic attack, and 8 (20%) developed pericardial effusions requiring pericardiocentesis. Four cases (9%) were complicated by perforation of the LAA, with 2 of these patients requiring open surgical correction. CONCLUSION This multicenter experience revealed that pericardial suture ligation with the LARIAT system is technically feasible and acutely efficacious. However, additional improvements are required to minimize the rate of pericardial complications. A randomized study is warranted to accurately define the long-term efficacy and safety profile of percutaneous epicardial suture ligation.

Multicenter experience with extraction of the Riata/Riata ST ICD lead

BACKGROUND In November 2011, the Food and Drug Administration issued a class I recall of Riata and Riata ST implantable cardioverter-defibrillator leads. Management recommendations regarding the recall have remained controversial. OBJECTIVE Data regarding the safety and feasibility of extraction of Riata implantable cardioverter-defibrillator leads are limited. METHODS We performed a retrospective study of patients undergoing extraction of Riata/Riata ST leads at 11 centers. RESULTS Between July 2003 and April 2013, 577 Riata/Riata ST leads were extracted from 577 patients (Riata 467, [84%]; Riata ST 89, [16%]). Complete procedural success achieved in 99.1%. The cohort was 78% men, with a mean age of 60 years and a mean left ventricular ejection fraction of 34% ± 14%. The mean implant duration was 44.7 months (range 0-124.6 months). The majority of leads extracted were for infection (305 [53.0%]) and 220 (35.7%) for lead malfunction. Evaluation for lead integrity was performed in 295 cases. Of these, 34.9% were found to have externalized cables. Implant duration was significantly longer in leads with externalized cables (P < .0001). No difference in lead integrity was noted between Riata and Riata ST leads (11.7% vs. 17.7% failure; P = .23). Among leads in which cable externalization was noted, laser sheaths were used more frequently (P = .01). Major complications included 3 superior vena cava/right ventricular perforations requiring surgical intervention with 1 death 12 days after the procedure and 1 pericardial effusion requiring percutaneous drainage (0.87%). CONCLUSION Extraction of the Riata/Riata ST leads can be challenging, and leads with externalized cables may require specific extraction techniques. Extraction of the Riata/Riata ST leads can be performed safely by experienced operators at high-volume centers with a complication rate comparable to published data.

Catheter ablation of scar-related atypical atrial flutter

AIMS The aim of the study was to assess the impact of isthmus location of atypical atrial flutters/atrial tachycardias (ATs) on outcomes of catheter ablation. Atrial tachycardias are clinically challenging arrhythmias that can occur in the presence of atrial scar--often due to either cardiac surgery or prior ablation for atrial fibrillation. We previously demonstrated a catheter ablation approach employing rapid multielectrode activation mapping with targeted entrainment manoeuvrs. However, the role that AT isthmus location plays in acute and long-term success of ablation remains uncertain. METHODS AND RESULTS Retrospective multicenter analysis of 91 consecutive AT patients undergoing ablation using a systematic four-step approach: (i) high-density activation mapping; (ii) analysis of atrial activation to identify wavefronts of electrical propagation; (iii) targeted entrainment of putative channels; and (iv) irrigated radiofrequency ablation of constrained regions of the circuit. Clinical outcomes, procedural details, and clinical profiles were determined. A total of 171 ATs (1.9 ± 1.0 per patient, 26% septal ATs) were targeted for ablation. The acute success rates were 97 and 77% for patients with either non-septal ATs or septal ATs, respectively (P = 0.0023). Similarly, the long-term success rates were 82 and 67% for patients with either no septal ATs or at least one septal AT, respectively (P = 0.1057). The long-term success rates were 75, 88, and 57% for patients with ATs associated with prior catheter ablation, cardiac surgery or MAZE, and idiopathic atrial scar, respectively. CONCLUSION Catheter ablation of AT can be successfully performed employing a strategy of combined high-density activation and entrainment mapping. Septal ATs are associated with higher rates of acute and long-term recurrences.

Adjunctive Renal Sympathetic Denervation to Modify Hypertension as Upstream Therapy in the Treatment of Atrial Fibrillation (H-FIB) Study: Clinical Background and Study Design

Hypertension is the most important risk factor directly attributable to the high prevalence of atrial fibrillation (AF), and is one of the few modifiable risk factors for AF. Activation and overactivity of the sympathetic nervous system (SNS) have been implicated in the pathogenesis of both essential hypertension and AF. Catheter‐based renal sympathetic denervation (RSDN) appears to be an effective adjunctive treatment for refractory hypertension, and may be beneficial in other conditions characterized by SNS overactivity, such as left ventricular hypertrophy and atrial arrhythmias.

Objective quality assessment of atrial fibrillation ablation: A novel scoring system

health-care processes and overall patient outcomes. 1 However, these critical evaluations have been lacking in the field of interventional cardiac electrophysiology and in the assessment of catheter ablation for atrial fibrillation (CAAF) in particular. The clinical success of CAAF, the most common ablation procedure performed worldwide, is currently reported in terms of atrial fibrillation (AF) recurrence rates, an assessment strategy with considerable limitations. Since recognition of AF recurrence is largely based on the presence of symptoms and as recurrences are frequently asymptomatic, 2 this strategy can substantially underestimate the true incidence of postablation AF. Even when noninvasive monitoring is routinely used after ablation, the sensitivity for the detection of asymptomatic AF recurrences depends on the protocol used, with more aggressive arrhythmia surveillance certain to identify higher rates of recurrence. 3 Furthermore, the definition of AF burden (symptomatic and asymptomatic) used to define recurrence varies and there are discrepancies as to whether a requirement for antiarrhythmic drugs is considered separately from maintenance of sinus rhythm without adjuvant pharmacotherapy. 4 As a result, there are wide variations in reported recurrence rates after CAAF among centers and the factors accounting for these differences have not been systematically delineated. In addition, and perhaps most importantly, reported success rates do not account for procedural safety, precluding meaningful comparisons between different techniques. The appraisal of CAAF requires a more objective evaluation that combines data on the quality of lesion delivery, complication rates, and clinical outcomes. To develop a more comprehensive, less biased criterion to assess the quality of CAAF and standardize comparisons between ablation strategies, we devised a novel quantitative scoring system based on more objective measures of the ablation procedure and a weighted assessment of procedurerelated complications, which we have termed the AF ablation (AFA) score.

Renal Sympathetic Denervation Using an Electroanatomic Mapping System

![Figure][1] A 54-year-old man with refractory hypertension presented for catheter-based renal sympathetic denervation. Three-dimensional (3D) geometric reconstruction of the renal arteries and real-time visualization of the ablation catheter were performed with an irrrigated straight-tipped

STRUCTURAL AND FUNCTIONAL DIFFERENCES IN PHYSIOLOGICAL VERSUS PATHOLOGICAL PATTERNS OF LEFT ATRIAL REMODELING: A SPECKLE TRACKING STRAIN ECHOCARDIOGRAPHY STUDY

methods: A total of 143 subjects were studied in two groups: 91 healthy volunteers included 77 athletes, and 52 patients with diastolic dysfunction including 27 patients with AF. LAVi was correlated with diastolic function and speckle tracking derived global LAƐ and LVƐ. results: For patients, LAƐ and LVƐ (Fig. A and B) independently predicted LAVi (R2=0.51, P=0.04 for both). In contrast, volunteers showed higher LAƐ (40±10 vs. 23±12%, P<0.01) despite similar LAVi (P=0.21). LAƐ in volunteers correlated with LV early (r=0.36; P<0.01), late diastolic (r=0.39; P<0.01) annular velocities and end-diastolic volume (r=0.27; P=0.02). LAƐ showed diagnostic value in differentiating pathologic and physiologic LA remodeling (Fig. C; AUC, 0.84, P< 0.01).