Gender-specific outcomes after percutaneous left atrial appendage closure: A nationwide readmission database analysis.

INTRODUCTION: Thromboembolism-associated stroke is the most feared complication of atrial fibrillation (AF). Percutaneous left atrial appendage closure (pLAAC) is indicated for stroke prevention in patients with AF who can not tolerate long-term anticoagulation. We aim to study gender differences in peri-procedural and readmissions outcomes in pLAAC patients. METHODS: Using the national readmission database from January 2016 to December 2018, AF patients undergoing the pLAAC procedure were identified. We used multivariate logistic regression analyses and time-to-event Cox regression analyses to conduct the study. Propensity matching with the Greedy method was done for the accuracy of results. RESULT: A total of 28 819 patients were included in our study. Among them 11 946 (41.5%) were women and 16 873 (58.6%) were men. The mean age of overall population was 76.1 ± 8.5 years, with women ~1 year older than men. The overall rate of complications was higher in women (8.6% vs. 6.6%, p < .001), primarily driven by bleeding-related complications, that is, major bleed (odds ratio [OR]: 1.32 95% confidence interval [CI]: 1.03-1.69, p = .029), blood transfusion (OR: 1.45, 95% CI: 1.06-1.97, p = .019), and cardiac tamponade (OR: 1.80, 95% CI: 1.13-2.89, p = .014). Women had two times higher peri-procedural ischemic stroke. There was no difference in peri-procedural mortality. Women remained at 20% and 13% higher risk for readmission at 30 days and 6 months of discharge. CONCLUSION: Women had higher peri-procedural complications and were at higher risk of readmissions at 30 days and 6 months. However, there was no difference in mortality during the index hospitalization. Further studies are necessary to determine causality.

Perioperative hematoma with subcutaneous ICD implantation: Impact of anticoagulation and antiplatelet therapies.

BACKGROUND: The safety of perioperative anticoagulation (AC) and antiplatelet (AP) therapy with subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation is unknown. The purpose of this study was to identify the risk factors associated with hematoma complicating S-ICD implantation. METHODS: Records were retrospectively reviewed from 200 consecutive patients undergoing S-ICD implantation at two academic medical centers. A hematoma was defined as a device site blood accumulation requiring surgical evacuation, extended hospital stay, or transfusion. RESULTS: Among 200 patients undergoing S-ICD implantation (age 49 ± 17 years, 67% men), 10 patients (5%) had a hematoma, which required evacuation in six patients (3%). Warfarin was bridged or uninterrupted in 12 and 13 patients, respectively (6% and 6.5%). Four of 12 patients with warfarin and bridging AC (33%) and two of 13 patients with uninterrupted warfarin (15%) developed a hematoma. Neither of the two patients with uninterrupted DOAC had a hematoma. No patients on interrupted AC without bridging (n = 26, 13 with warfarin, 13 with DOAC) developed a hematoma. A hematoma was also more likely with the use of clopidogrel (n = 4/10 vs 10/190, 40% vs 5.3%, P < 0.0001) in combination with aspirin in 12/14 patients. Any bridging AC (odds ratio [OR] 10.3, 1.8-60.8, P = 0.01), clopidogrel (OR 10.0, 1.7-57.7, P = 0.01), and uninterrupted warfarin without bridging (OR 11.1, 1.7-74.3, P = 0.013) were independently associated with hematoma formation. CONCLUSION: AC and/or AP therapy with clopidogrel appears to increase the risk for hematoma following S-ICD implantation. Interruption of AC without bridging should be considered when it is an acceptable risk to hold AC.

Safety profiles of percutaneous left atrial appendage closure devices: An analysis of the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database from 2009 to 2016.

BACKGROUND: Percutaneous left atrial appendage closure (LAAC) is a viable option for AF patients who are unable to tolerate long-term oral anticoagulation (OAC). OBJECTIVE: We sought to assess the safety of two commonly used percutaneous devices for LAA closure in the United States by analysis of surveillance data from the FDA Manufacturer and User Facility Device Experience (MAUDE) database. METHODS: The MAUDE database was queried between May 1, 2006 and May 1, 2016 for LARIAT® (SentreHEART Inc., Redwood City, CA, USA) and WATCHMAN™ (Boston Scientific Corp., Marlborough, MA, USA) devices. Among 622 retrieved medical device reports, 356 unique and relevant reports were analyzed. The cumulative incidence of safety events was calculated over the study period and compared between the two devices. RESULTS: LAAC was performed with LARIAT in 4,889 cases. WATCHMAN was implanted in 2,027 patients prior to FDA approval in March 2015 and 3,822 patients postapproval. The composite outcome of stroke/TIA, pericardiocentesis, cardiac surgery, and death occurred more frequently with WATCHMAN (cumulative incidence, 1.93% vs. 1.15%; P = 0.001). The same phenomenon was observed when comparing the WATCHMAN pre- and postapproval experiences for the composite outcome, as well as device embolization, cardiac surgery, and myocardial infarction. CONCLUSIONS: MAUDE-reported data show that postapproval, new technology adoption is fraught with increased complications. Improved collaboration between operators, device manufacturers, and regulators can better serve patients through increased transparency and practical postmarket training and monitoring mechanisms.

Incidence, predictors and outcomes of hematoma after ICD implantation: An analysis of a nationwide database of 85,276 patients.

BACKGROUND: Pocket hematoma is one of the most common complications following cardiac device implantation. This study examined the impact of this complication on in-hospital outcomes following Implantable Cardioverter Defibrillator (ICD) implantation. METHODS: Data from Nationwide Inpatient Sample (NIS) 2010 was queried to identify all primary implantations of ICDs and Cardiac Resynchronization Therapy Defibrillators (CRT-D) during the year 2010 using ICD-9 codes. We then identified the patients who experienced a procedure related hematoma during the hospital stay. We compared the outcomes of the patients with and without a hematoma complication. All analyses were performed using SPSS 20 complex samples using appropriate weights to adjust for the complex sampling design of the national database. RESULTS: Out of a total of 85,276 primary ICD implantations in the year 2010, 2233 (2.6% of the implantations) were complicated by a hematoma. Increased age (p < 0.001), and comorbidities such as congestive heart failure (odds ratio (OR) - 1.86, p < 0.001), coagulopathy (OR - 2.3, p < 0.001) and renal failure (OR - 1.52, p < 0.001) were associated with an increased risk of pocket hematoma formation. Patients who developed a hematoma had a longer hospitalization (9.1 days versus 5.5 days, p < 0.001) and higher in-hospital costs ($56,545 versus $47,015, p < 0.001) compared to patients who did not have a hematoma. Overall mortality associated with ICD implantation was low (0.6%), and hematoma formation did not adversely affect mortality (0.6% versus 0.4%, p = 0.63). CONCLUSION: Hematoma occurs infrequently after ICD implantation, however, it adversely impacts the cost of procedure and length of stay.

Cardiac Resynchronization Therapy: US Trends and Disparities in Utilization and Outcomes.

BACKGROUND: The use of cardiac resynchronization therapy (CRT) has increased significantly since its initial approval in 2001 for use in patients with advanced heart failure. However, trends in utilization of CRT have not been systematically characterized. METHODS AND RESULTS: We used the Nationwide Inpatient Sample database to identify all patients with CRT implantation during 2002 to 2010. The overall trends in CRT device implantation, patient characteristics, and outcomes were examined in detail and compared among demographic subgroups. During 2002 to 2010, a total of 374,202 CRT procedures were recorded. Significant and persistent gender and racial disparities favoring men (71.4%) and white (79.6%), respectively, were noted in all years. The highest number of CRT devices were implanted in the 65- to 84-year age group (64.6%), with significant increase in number of CRT implants in older patients ≥ 85 years over the years (P = 0.02). The CRT-associated in-hospital mortality improved from 1.08% in 2003 to 0.70% in 2010 (P = 0.03). The correlates of higher mortality included males (0.93% versus 0.71% in females; P = 0.04) and older age (age ≥ 85 years had 1.5% mortality versus 0.8% for age < 85 year; P < 0.001). The mean hospital length of stay for CRT decreased, while mean CRT-associated hospital charges increased progressively over the years. Factors associated with higher charges were gender (males > females), older age, and greater comorbidities. CONCLUSIONS: CRT implantation is a relatively safe procedure that has become safer in higher risk patients. However, significant disparities in CRT utilization exist in certain demographic subgroups, and these disparities have persisted across the years.

Impact of Tricuspid Regurgitation on the Success of Atrioventricular Node Ablation for Rate Control in Patients With Atrial Fibrillation: The Node Blast Study.

Atrioventricular node (AVN) ablation is an effective treatment for symptomatic patients with atrial arrhythmias who are refractory to rhythm and rate control strategies where optimal ventricular rate control is desired. There are limited data on the predictors of failure of AVN ablation. Our objective was to identify the predictors of failure of AVN ablation. This is an observational single-center study of consecutive patients who underwent AVN ablation in a large academic center. Baseline characteristics, procedural variables, and outcomes of AVN ablation were collected. AVN "ablation failure" was defined as resumption of AVN conduction resulting in recurrence of either rapid ventricular response or suboptimal biventricular pacing. A total of 247 patients drug refractory AF who underwent AVN ablation at our center with a mean age of 71 ± 12 years with 46% being males were included. Ablation failure was seen in 11 (4.5%) patients. There were no statistical differences between patients with "ablation failure" versus "ablation success" in any of the baseline clinical variables. Patients with moderate-to-severe tricuspid regurgitation (TR) were much more likely to have ablation failure than those with ablation success (8 [73%] vs 65 [27%]; p = 0.003). All 11 patients with ablation failure had a successful redo procedure, 9 with right and 2 with the left sided approach. On multivariate analysis, presence of moderate-to-severe TR was found to be the only predictor of failure of AVN ablation (odds ratio 9.1, confidence interval 1.99 to 42.22, p = 0.004). In conclusion, moderate-to-severe TR is a strong and independent predictor of failure of AVN ablation.

Initial real world experience with a novel insertable (Reveal LinQ(@Medtronic)) compared to the conventional (Reveal XT(@Medtronic)) implantable loop recorder at a tertiary care center - Points to ponder!

INTRODUCTION: Limited data is available regarding the novel Reveal LinQ (LinQ) which is a new generation implantable loop recorders (ILRs). METHODS: We performed a prospective, observational study of all consecutive patients undergoing conventional (Reveal XT; XT) and LinQ devices at our institution between January 2012 and December 2014. RESULTS: A total of 217 patients underwent ILR implantation. XT was implanted in 105 and LinQ in 112 patients. There were no significant differences in baseline characteristics between the two groups. LinQ implantation using the manufacturer's technique termed, "manufacturer's method" group had significantly higher incidence of pocket infection compared to XT (6/50, 12% vs 3/105, 3%, p=0.032). With modifications to the LinQ implantation technique (using a conventional scalpel and placing a suture when needed to the incision) termed "modified method" group, the rate of infection has decreased significantly compared to "manufacturer's method group" (0/62, 0% vs 6/50, 12%, p=0.004) (Table 3). In multivariate regression analysis, the only independent predictors of infection were younger age (OR 0.95; p=0.04), insertion of LinQ device (OR 30.02; p=0.006) and procedure time (OR 1.07; p=0.03). CONCLUSION: In our single-center, prospective, observational study we found that with the current implantable techniques, the novel insertable LinQ device is associated with increased risk of complications.

Endocardial (Watchman) vs epicardial (Lariat) left atrial appendage exclusion devices: Understanding the differences in the location and type of leaks and their clinical implications.

BACKGROUND: Watchman and Lariat left atrial appendage (LAA) occlusion devices are associated with LAA leaks postdeployment. OBJECTIVE: The purpose of this study was to compare the incidence, characteristics, and clinical significance of these leaks. METHODS: We performed a multicenter prospective observational study of all patients who underwent LAA closure. Baseline, procedural, and imaging variables along with LAA occlusion rates at 30-90 days and 1-year postprocedure were compared. RESULTS: A total of 478 patients (219 with the Watchman device and 259 with the Lariat device) with successful implants were included. Patients in the Lariat group had a higher CHADS2 (congestive heart failure, hypertension, age >74 years, diabetes, stroke) score and a larger left atrium and LAA. A total of 79 patients (17%) had a detectable leak at 1 year. More patients in the Watchman group had a leak compared with those in the Lariat group (46 [21%] vs 33 [14%]; P = .019). All the leaks were eccentric (edge effect) in the Watchman group and concentric (gunny sack effect) in the Lariat group. The size of the leak was larger in the Watchman group than in the Lariat group (3.10 ± 1.5 mm vs 2.15 ± 1.3 mm; P = .001). The Watchman group had 1 device embolization requiring surgery and 2 pericardial effusions requiring pericardiocentesis. In the Lariat group, 4 patients had cardiac tamponade requiring urgent surgical repair. Three patients in each group had a cerebrovascular accident and were not associated with device leaks. CONCLUSION: The Lariat device is associated with a lower rate of leaks at 1 year as compared with the Watchman device, with no difference in rates of cerebrovascular accident. There was no correlation between the presence of residual leak and the occurrence of cerebrovascular accident.

Effect of atrial fibrillation ablation on gastric motility: the atrial fibrillation gut study.

BACKGROUND: Collateral damage to the vagal nerve and the upper gastrointestinal (UGI) system during atrial fibrillation ablation has not been systematically evaluated. METHODS AND RESULTS: We performed a prospective, observational study assessing the effect of atrial fibrillation ablation on the function of the vagus nerve/UGI system. All patients underwent esophageal manometry, gastric emptying study, and sham-feeding test (corresponding to esophageal, gastric, and small intestinal function evaluation, respectively) before ablation (baseline) and subsequently at 24 hours, 90 days, and 180 days after the procedure. In addition, UGI symptom assessment using the patient assessment of upper gastrointestinal disorders-symptom severity index (PAGI-SYM) questionnaire was performed at baseline and during each of the subsequent evaluations. Of the 27 patients enrolled in the study, 9 (33%) patients had abnormal UGI function at baseline; defined as at least one of the 3 abnormal tests. At 24 hours after the radiofrequency catheter ablation, 20 (74%) patients had at least 1 new abnormality on the UGI function tests (P<0.001). New onset esophageal dysmotility, delayed gastric emptying time, and abnormal sham-feeding tests were observed in 13 (48%), 13 (48%), and 9 (33%) patients, respectively. Mean PAGI-SYM scores increased from 7.78±6.6 at baseline to 15.56±13.4 (P=0.002) at 24 hours. New onset abnormalities persisted in 9 (33%) patients at 3 months and normalized in all patients at 6 months. CONCLUSIONS: Atrial fibrillation ablation results in functional impairment of the UGI system, including the esophagus, stomach, and small intestine. This impairment is transient and is probably mediated by the injury to the components of the vagal nerve. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov. Unique Identifier: NCT01396356.

Pulmonary vein isolation for atrial fibrillation in the postpneumonectomy population: a feasibility, safety, and outcomes study.

BACKGROUND: Pulmonary vein isolation (PVI) of the remnant pulmonary vein (PV) stumps in pneumonectomy patients has not been well characterized. METHODS: This is a multicenter observational study of patients with a remnant PV stump after pneumonectomy. Consecutive patients with a history of pneumonectomy and who had undergone RF ablation for drug refractory AF were identified from the AF database at the participating institutions. RESULTS: There were 15 patients in whom pneumonectomy was performed, for resection of tumors in 10, infection in 4, and bullae in 1 patient and who underwent RF ablation for AF. The mean age was 63 ± 7 years. The stumps were from the right lower PV in 5, left upper PV in 5, left lower PV in 3, and right upper PV in 2 patients. All the PV stumps were electrically active with PV potentials and 9 (60%) of them had triggered activity. PVI was performed in 14 and focal isolation in 1 patient. At 1-year follow-up, 80% were free of AF, off of antiarrhythmic medications. CONCLUSION: PV stumps in AF patients with previous pneumonectomy are electrically active and are frequently the sites of active firing. Isolation of these PV stumps can be accomplished safely and effectively using catheter ablation with no practical concern for PV stenosis or compromising PV stump integrity.

Lone atrial fibrillation: electrophysiology, risk factors, catheter ablation and other non-pharmacologic treatments.

Atrial fibrillation occurring in the absence of cardiovascular disease in individuals younger than 60 years is known as lone atrial fibrillation. Nearly 1-12% of atrial fibrillation is considered to be lone atrial fibrillation. As our understanding of atrial fibrillation grows, we wonder as to whether there is such as thing as "lone" atrial fibrillation? We know that male sex, obesity, obstructive sleep apnea, alcohol consumption and endurance sports increase the risk of developing lone atrial fibrillation. Family history of atrial fibrillation increases the risk strongly and there are several recognized mutations that are causative of lone atrial fibrillation. Common triggers for origin of atrial fibrillation are the pulmonary veins. The atrial substrate provides the reentry circuits for perpetuating the arrhythmia. The autonomic nervous system is a key modulator and allows the continuation of the atrial fibrillation. Catheter ablation has been very effective in the treatment of this condition. The ablation procedure involves isolation of the pulmonary veins, antrum, complex fractionated electrograms and other sites. Alternatively surgical techniques can be used to isolate the pulmonary veins and surgical techniques have evolved to minimally invasive procedures and these are as effective as catheter ablation. Early intervention improves the left atrial remodeling and may lead to fewer recurrences.

Left Atrial Appendage Ligation and Ablation for Persistent Atrial Fibrillation: The LAALA-AF Registry.

OBJECTIVES: This study was intended to evaluate the impact of adding the left atrial appendage (LAA) closure system (LARIAT) procedure to conventional atrial fibrillation (AF) ablation in patients with persistent AF. BACKGROUND: Percutaneous endoepicardial LARIAT may result in both mechanical and electrical exclusion of the LAA and aid in improving the outcomes of catheter ablation by eradicating the LAA triggers and altering the substrate. METHODS: We performed a prospective observational study of patients with persistent AF referred for AF ablation. Patients underwent LAA ligation with LARIAT procedure before undergoing AF ablation (LARIAT group). Age- and sex-matched persistent AF patients undergoing AF ablation during the same time frame were included in the control group (ablation-only group). RESULTS: A total of 138 patients were included in the study, with 69 patients in the LARIAT group. The mean age of the population was 67 ± 10 years, with 96 (70%) men. Left atrial (LA) size, CHADS2, CHADSVasc, and HAS-BLED scores were higher in the LARIAT group when compared with the ablation-only group. There were no differences in the type of lesions during AF ablation between the groups. The primary outcome of freedom from AF at 1 year off antiarrhythmic therapy after 1 ablation procedure was higher in the LARIAT group (45 [65%] vs. 27 [39%]; p = 0.002). More patients in the ablation-only group underwent repeat ablation because of AF recurrence (11 [16%] vs. 23 [33%]; p = 0.018). CONCLUSIONS: In patients with persistent AF, addition of LAA ligation with the LARIAT device to conventional ablation appears to improve the success rate of AF ablation.

Incidence, predictors, and clinical course of atrial tachyarrhythmias in patients with pulmonary hypertension.

BACKGROUND: The prevalence and predictors of atrial tachyarrhythmias (ATa) in patients with pulmonary hypertension (PH) is less well understood. METHODS: We performed a retrospective study including 311 patients with PH, confirmed by right heart catheterization in our center between 2007 and 2011. Baseline characteristics, clinical, echocardiographic, and hemodynamic data were collected and compared between patients with and without ATa. RESULTS: The mean age was 61 ± 13 years with 64 % females. The mean pulmonary artery pressure (mPAP) was 46 ± 20 mmHg, mean left ventricular ejection fraction (LVEF) was 55 ± 13 %, and mean pulmonary capillary wedge pressure (PCWP) was 19 ± 9 mmHg. Of the 311 patients with PH, 121 (39 %) patients had ATa. Patients with ATa were older (p<0.001) and were more likely to have systemic hypertension (p=0.03), diabetes (p=0.015), coronary artery disease (p<0.001), heart failure (p<0.001), mitral regurgitation (p=0.001), impaired LVEF (p=0.02), and left atrial enlargement (p<0.001). There was no difference in the prevalence of ATa in mild, moderate, or severe PH. The mean PCWP was higher in patients with ATa (17.9 ± 9 vs 20.3 ± 8; p=0.022). In multivariate analysis using Cox-proportional hazard model, the independent predictors of mortality were age (HR 1.05; p=0.003), coronary artery disease (HR 2.34; p=0.047), LVEF (HR 0.793; p=0.023), and mPAP (HR 1.023; p=0.003). CONCLUSION: ATa are common in patients with PH. Left heart disease, left atrial enlargement, and elevated PCWP but not right atrial enlargement or mPAP predict the occurrence of ATa in patients with PH.

MediGuide-impact on catheter ablation techniques and workflow.

Since the introduction of percutaneous intervention in modern medical science, specifically cardiovascular medicine fluoroscopy has remained the gold standard for navigation inside the cardiac structures. As the complexity of the procedures continue to increase with advances in interventional electrophysiology, the procedural times and fluoroscopy times have proportionately increased and the risks of radiation exposure both to the patients as well as the operator continue to rise. 3D electroanatomic mapping systems have to some extent complemented fluoroscopic imaging in improving catheter navigation and forming a solid platform for exploring the electroanatomic details of the target substrate. The 3D mapping systems are still limited as they continue to be static representations of a dynamic heart without being completely integrated with fluoroscopy. The field needed a technological solution that could add a dynamic positioning system that can be successfully incorporated into fluoroscopic imaging as well as electroanatomic imaging modalities. MediGuide is one such innovative technology that exploits the geo-positioning system principles. It employs a transmitter mounted on the X-ray panel that emits an electromagnetic field within which sensor-equipped diagnostic and ablation catheters are tracked within prerecorded fluoroscopic images. MediGuide is also integrated with NavX mapping system and helps in developing better 3D images by field scaling-a process that reduces field distortions that occur from impedance mapping alone. In this review, we discuss about the principle of MediGuide technology, the catheter ablation techniques, and the workflow in the EP lab for different procedures.

Catheter ablation of atrial fibrillation in patients with mechanical mitral valve: long-term outcome of single procedure of pulmonary vein antrum isolation with or without nonpulmonary vein trigger ablation.

INTRODUCTION: It is unclear whether extended pulmonary vein antrum isolation (PVAI) plus nonpulmonary vein (non-PV) trigger elimination prevents more arrhythmia recurrence than PVAI alone in patients with mechanical mitral valve (MMV) undergoing AF ablation. This study compared the efficacy and long-term outcome of 2 ablation strategies--PVAI alone versus extended PVAI plus non-PV trigger elimination--for the treatment of AF in patients with MMV. METHODS AND RESULTS: One hundred and nine consecutive AF patients with MMV were divided into 2 groups: standard PVAI was performed in group 1 (N = 45); in group 2 (N = 64) PVAI was extended to the LA posterior wall, LA septum, and CS; and all non-PV triggers were eliminated. Patients were followed up for 3 years. At the 12th month, 7 (15.6%) patients in group 1, and 39 (60.9%) patients in group 2 were arrhythmia free (log-rank P < 0.001). Four patients (8.9%; 3 cases of AT and 1 case of AF) from group 1, and 12 patients (18.8%; 9 cases of AT, and 3 cases of AFL) from group 2 experienced very late recurrence. At 36 ± 7 months follow-up, the cumulative recurrence after a single procedure was 42/45 (93.3%) in group 1, and 37/64 (57.8%) in group 2 (log-rank P < 0.001). CONCLUSION: Compared with the standard PVAI alone, a strategy including extended PVAI and non-PV trigger elimination is associated with a higher 12-month and long-term arrhythmia-free survival in patients with MMV undergoing AF ablation. Very late recurrence may occur years after the initial procedure with focal AT as the most common type of recurrent arrhythmia.

Percutaneous left ventricular assist devices in ventricular tachycardia ablation: multicenter experience.

BACKGROUND: Data on relative safety, efficacy, and role of different percutaneous left ventricular assist devices for hemodynamic support during the ventricular tachycardia (VT) ablation procedure are limited. METHODS AND RESULTS: We performed a multicenter, observational study from a prospective registry including all consecutive patients (N=66) undergoing VT ablation with a percutaneous left ventricular assist devices in 6 centers in the United States. Patients with intra-aortic balloon pump (IABP group; N=22) were compared with patients with either an Impella or a TandemHeart device (non-IABP group; N=44). There were no significant differences in the baseline characteristics between both the groups. In non-IABP group (1) more patients could undergo entrainment/activation mapping (82% versus 59%; P=0.046), (2) more number of unstable VTs could be mapped and ablated per patient (1.05±0.78 versus 0.32±0.48; P<0.001), (3) more number of VTs could be terminated by ablation (1.59±1.0 versus 0.91±0.81; P=0.007), and (4) fewer VTs were terminated with rescue shocks (1.9±2.2 versus 3.0±1.5; P=0.049) when compared with IABP group. Complications of the procedure trended to be more in the non-IABP group when compared with those in the IABP group (32% versus 14%; P=0.143). Intermediate term outcomes (mortality and VT recurrence) during 12±5-month follow-up were not different between both groups. Left ventricular ejection fraction ≤15% was a strong and independent predictor of in-hospital mortality (53% versus 4%; P<0.001). CONCLUSIONS: Impella and TandemHeart use in VT ablation facilitates extensive activation mapping of several unstable VTs and requires fewer rescue shocks during the procedure when compared with using IABP.

Feasibility and safety of uninterrupted rivaroxaban for periprocedural anticoagulation in patients undergoing radiofrequency ablation for atrial fibrillation: results from a multicenter prospective registry.

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.

Embryology and Anatomy of the Left Atrial Appendage: Why Does Thrombus Form?

The left atrial appendage (LAA) is a long tubular structure that opens into the left atrium. In patients with atrial fibrillation, the LAA develops mechanical dysfunction and fibroelastotic changes on the endocardial surface. The complex anatomy of the LAA makes it a good site for relative blood stasis. In addition, systemic factors exacerbate the hypercoagulable state, eventually resulting in endothelial dysfunction, release of tissue factor, and production of inflammatory cytokines and oxidative free radicals, and eventually initiating the coagulation cascade. Thus, the LAA is susceptible to thrombus formation and is the most common source of systemic thromboembolism.

Impact of nonfluoroscopic MediGuide™ tracking system on radiation exposure in radiofrequency ablation procedures (LESS-RADS registry)-an initial experience.

BACKGROUND: Radiation exposure in the electrophysiology (EP) lab is a major concern to most electrophysiologists. A new technology, MediGuide™ nonfluoroscopic catheter tracking system, has been used for the first time in the USA recently. We intended to evaluate the efficacy of this novel catheter tracking system in reducing radiation exposure. METHODS: We performed a prospective observational study by comparing the radiation exposure with MediGuide™ system to that of conventional mapping systems. The first 45 EP procedures performed with the MediGuide™ system were compared to 45 matched patients undergoing similar procedures during the same time frame using conventional mapping systems (CARTO and NavX) and fluoroscopy. We collected and compared baseline characteristics, procedural variables including fluoroscopic exposure between both groups. RESULTS: Forty-five patients underwent EP procedures using the MediGuide™ technology. They were matched with an equal number of patients with conventional mapping systems. Of the 45 patients included in the study, 33 underwent right atrial flutter ablations, 5 underwent atrioventricular nodal reentrant tachycardia ablations, 4 underwent ablation of Wolf-Parkinson-White syndrome, and 3 underwent EP studies with no ablation. There were no differences in mean age, gender distribution, and body mass index between the groups. Procedure duration in the MediGuide™ group was significantly lower than the duration in the conventional group (103 vs. 142 min, p = 0.03). The fluoroscopic time was significantly less during the procedures performed with the MediGuide™ technology when compared to the control group (8 vs. 21 min, p < 0.001). No major complications occurred during the procedures in either group. CONCLUSION: MediGuide™, a new nonfluoroscopic catheter tracking system, is associated with more than a 50 % reduction in fluoroscopic time when compared to conventional mapping systems.