Evaluation of a novel cardiac signal processing system for electrophysiology procedures: The PURE EP 2.0 study.

BACKGROUND: Intracardiac electrogram data remain one of the primary diagnostic inputs guiding complex ablation procedures. However, the technology to collect, process, and display intracardiac signals has known shortcomings and has not advanced in several decades. OBJECTIVE: The purpose of this study was to evaluate a new signal processing platform, the PURE EP™ system (PURE), in a multi-center, prospective study. METHODS: Intracardiac signal data of clinical interest were collected from 51 patients undergoing ablation procedures with PURE, the signal recording system, and the 3D mapping system at the same time stamps. The samples were randomized and subjected to blinded, controlled evaluation by three independent electrophysiologists to determine the overall quality and clinical utility of PURE signals when compared to conventional sources. Each reviewer assessed the same (92) signal sample sets and responded to (235) questions using a 10-point rating scale. If two or more reviewers rated the PURE signal higher than the control, it was deemed superior. RESULTS: A total of 93% of question responses showed consensus amongst the blinded reviewers. Based on the ratings for each pair of signals, a cumulative total of 164 PURE signals out of 218 (75.2%) were statistically rated as Superior for this data set (p < .001). Only 14 PURE signals out of 218 were rated as Inferior (6.4%). CONCLUSION: The PURE intracardiac signals were statistically rated as superior when compared to conventional systems.

State of Fluoroless Procedures in Cardiac Electrophysiology Practice.

In the past decade, the use of interventional electrophysiological (EP) procedures for the diagnosis and treatment of cardiac arrhythmias has exponentially increased. These procedures usually require fluoroscopy to guide the advancement and frequent repositioning of intracardiac catheters, resulting in both the patient and the operator being subjected to a considerable degree of radiation exposure. Although shielding options such as lead gowns, glasses, and pull-down shields are useful for protecting the operator, they do not lessen the patient's level of exposure. Furthermore, the prolonged use of lead gowns can exponentiate the onset of orthopedic problems among operators. Recent advancements in three-dimensional cardiac mapping systems and the use of radiation-free imaging technologies such as magnetic resonance imaging and intracardiac ultrasound allow operators to perform EP procedures with minimal or even no fluoroscopy. In this review, we sought to describe the state of fluoroless procedures in EP practice.

Should fast pathway ablation be reconsidered in typical atrioventricular nodal re-entrant tachycardia?

INTRODUCTION: Atrioventricular nodal re-entry tachycardia (AVNRT) is the most common, regular narrow-complex tachycardia. The established treatment is catheter ablation of the AV nodal slow pathway (SP). However, in a select group of patients with long PR intervals in sinus rhythm, SP ablation can lead to AV block due to the absence of robust anterograde conduction through the fast pathway (FP). This report aims to demonstrate that AV nodal FP ablation is a reasonable approach in patients with AVNRT and poor or absent anterograde FP conduction. METHODS AND RESULTS: Standard electrophysiology study techniques were used in the electrophysiology laboratory. Catheter ablations were performed using radiofrequency energy. Mapping of intracardiac activation was performed with electroanatomical mapping systems. Outcomes were assessed acutely during the procedure and during routine clinical follow-up. Six patients with first-degree AV block and recurrent AVNRT who underwent ablation of their tachycardia at our institution are presented. One patient underwent ablation of AV nodal SP resulting in high-degree AV block necessitating pacemaker implantation. The remaining five patients underwent ablation of the AV nodal FP guided by electroanatomical mapping of the earliest atrial activation in tachycardia. These five had successful treatment of the tachycardia with preservation of anterograde AV nodal conduction. Mapping and ablation approach to eliminate retrograde FP conduction are described. CONCLUSION: In select patients with AVNRT and poor anterograde FP conduction, retrograde FP ablation is reasonable and is less likely to result in AV block and pacemaker dependency.

Programming Cardiac Resynchronization Therapy for Electrical Synchrony: Reaching Beyond Left Bundle Branch Block and Left Ventricular Activation Delay.

BACKGROUND: QRS narrowing following cardiac resynchronization therapy with biventricular (BiV) or left ventricular (LV) pacing is likely affected by patient-specific conduction characteristics (PR, qLV, LV-paced propagation interval), making a universal programming strategy likely ineffective. We tested these factors using a novel, device-based algorithm (SyncAV) that automatically adjusts paced atrioventricular delay (default or programmable offset) according to intrinsic atrioventricular conduction. METHODS AND RESULTS: Seventy-five patients undergoing cardiac resynchronization therapy (age 66±11 years; 65% male; 32% with ischemic cardiomyopathy; LV ejection fraction 28±8%; QRS duration 162±16 ms) with intact atrioventricular conduction (PR interval 194±34, range 128-300 ms), left bundle branch block, and optimized LV lead position were studied at implant. QRS duration (QRSd) reduction was compared for the following pacing configurations: nominal simultaneous BiV (Mode I: paced/sensed atrioventricular delay=140/110 ms), BiV+SyncAV with 50 ms offset (Mode II), BiV+SyncAV with offset that minimized QRSd (Mode III), or LV-only pacing+SyncAV with 50 ms offset (Mode IV). The intrinsic QRSd (162±16 ms) was reduced to 142±17 ms (-11.8%) by Mode I, 136±14 ms (-15.6%) by Mode IV, and 132±13 ms (-17.8%) by Mode II. Mode III yielded the shortest overall QRSd (123±12 ms, -23.9% [P<0.001 versus all modes]) and was the only configuration without QRSd prolongation in any patient. QRS narrowing occurred regardless of QRSd, PR, or LV-paced intervals, or underlying ischemic disease. CONCLUSIONS: Post-implant electrical optimization in already well-selected patients with left bundle branch block and optimized LV lead position is facilitated by patient-tailored BiV pacing adjusted to intrinsic atrioventricular timing using an automatic device-based algorithm.

Prognostic Value of Her2/neu Expression in Gastrointestinal Stromal Tumors: Immunohistochemical Study.

BACKGROUND: Gastrointestinal stromal tumor (GIST) is a relatively rare type of neoplasms. In Egypt, it represents 2.5% of gastrointestinal tumors and 0.3% of all malignancies. Most of the GISTs develop in the stomach. AIM: To reveal the significance of Her2/neu immunohistochemical expression in GIST and its correlation with other histopathologic parameters and tumor relapse after regular follow-up. PATIENTS AND METHODS: This study is a retrospective and prospective cohort. It included 32 patients with GISTs, who were resectable with no distant metastasis. Immunohistochemical staining by Her2/neu was performed after complete surgical resection of the tumors with preservation of the pseudocapsule. RESULTS: In total, 53.1% of cases were men and 46.9% women. Tumors were classified into low-risk (25%), intermediate-risk (21.9%), and high-risk groups (53.1%). Her2/neu expression was negative in 56.3% of GISTs and positive in 43.7%. Its expression was significantly correlated with risk grade (P = .04), tumor size (P = .001), mitotic count (P = .00), and increased risk of relapse (P = .00). Furthermore, tumor relapse was significantly correlated with the tumor mitotic counts (P = .00). Using kappa agreement test, it showed that 4 mitotic counts/50 high-power fields (HPF) was the cutoff value with which the tumor might be associated more with relapse, with 83% sensitivity, 70% specificity, and P value of .003. CONCLUSIONS: Her2/neu might be used as an independent prognostic marker for tumor recurrence after complete resection of GIST, and the cutoff value of mitotic count that might predict tumor relapse is 4/50 HPF. However, more clinical studies with greater number of cases with fluorescent in situ hybridization integration are recommended.

Initial Experience With High-Risk Patients Excluded From Clinical Trials: Safety of Short-Term Anticoagulation After Left Atrial Appendage Closure Device.

BACKGROUND: The implantation of left atrial appendage closure device (WATCHMAN, Boston Scientific, Natick, MA) is an alternative option to oral anticoagulation (OAC) for stroke prevention in atrial fibrillation. Patients require short-term OAC after implantation to avoid device thrombosis. The 2 clinical trials that assessed this device excluded patients thought not to be candidates for OAC. As such, little is known about the safety of this strategy in patients with previous major bleeding events. METHODS AND RESULTS: All 20 consecutive patients with history of spontaneous major bleeding while on OAC who had subsequently undergone WATCHMAN device implantation at our institution were included. A newly conceived multidisciplinary Atrial Fibrillation Stroke Prevention Center evaluated patients for candidacy for device implantation and subsequent antithrombotic therapy. The primary outcome was spontaneous major bleeding while receiving short-term postprocedural OAC. Median CHA2DS2-VASc and HAS-BLED scores were 5 (quartiles 5-6) and 5 (quartiles 4-5), respectively. Previous major bleeding events were major gastrointestinal bleeding, intracranial bleeding, spontaneous hemopericardium with cardiac tamponade, and hemarthrosis in 11, 7, 1, and 1 patients, respectively. None of the patients had spontaneous major bleeding during the course of OAC after device implantation. In 1 patient, OAC was discontinued after 40 days because of mechanical fall with head trauma resulting in subdural hematoma with no associated neurological deficits; this was managed conservatively. CONCLUSIONS: With careful multidisciplinary evaluation, a short course of OAC after WATCHMAN device implantation in patients with previous spontaneous major bleeding events is associated with low risk of recurrent spontaneous major bleeding.

Evaluation oF Epicardial Fat and Carotid Intima-Media Thickness in Obese Children.

BACKGROUND: Epicardial fat has a role in cardiovascular diseases. OBJECTIVES: To assess epicardial fat and its relation with carotid intima-media thickness (IMT) in obese adolescents with metabolic syndrome (MetS). PATIENTS AND METHODS: The study included 60 obese adolescents and 25 control subjects. According to the presence or absence of MetS, obese subjects were divided into two subgroups. We measured weight, height, calculated Body Mass Index, waist circumference, hip circumference, systolic blood pressure, diastolic blood pressure and biochemical parameters (fasting glucose, total cholesterol, triglycerides, high density lipoprotein cholesterol, and low density lipoprotein cholesterol, High sensitivity C-reactive protein, fasting insulin, a homeostasis model assessment index of insulin resistance. plus an echocardiographic examination with measurement of epicardial adipose tissue thickness (EATT). RESULTS: Left ventricular mass index measurements were significantly higher in MetS group than both non-MS and control groups. The MetS and non-MetS obese patients had significantly higher carotid IMT in comparison to the control group. Carotid IMT measurements were significantly higher in MetS group had than both non-MetS and control groups. Also, EATT was significantly increased in patients with MetS compared to control group. Among MetS obese group, EATT was positively correlated with body mass index-standard deviation score, waist circumference, fasting glucose, fasting insulin, insulin resistance, triglyceride levels, left ventricular thickness, left ventricular mass index and myocardial performance index. EATT was found to be the only predictor of carotid IMT. CONCLUSIONS: EATT is closely related to carotid IMT and early cardiac dysfunction in obese adolescents with MetS.

Radiofrequency Ablation of Persistent Atrial Fibrillation: Diagnosis-to-Ablation Time, Markers of Pathways of Atrial Remodeling, and Outcomes.

BACKGROUND: Various ablation strategies of persistent atrial fibrillation (PersAF) have had disappointing outcomes, despite concerted clinical and research efforts, which could reflect progressive atrial fibrillation-related atrial remodeling. METHODS AND RESULTS: Two-year outcomes were assessed in 1241 consecutive patients undergoing first-time ablation of PersAF (2005-2012). The time intervals between the first diagnosis of PersAF and the ablation procedures were determined. Patients had echocardiograms and measures of B-type natriuretic peptide and C-reactive protein before the procedures. The median diagnosis-to-ablation time was 3 years (25th-75th percentiles 1-6.5). With longer diagnosis-to-ablation time (based on quartiles), there was a significant increase in recurrence rates in addition to an increase in B-type natriuretic peptide levels (P=0.01), C-reactive protein levels (P<0.0001), and left atrial size (P=0.03). The arrhythmia recurrence rates over 2 years were 33.6%, 52.6%, 57.1%, and 54.6% in the first, second, third, and fourth quartiles, respectively (P(categorical)<0.0001). In Cox Proportional Hazard analyses, B-type natriuretic peptide levels, C-reactive protein levels, and left atrial size were associated with arrhythmia recurrence. The diagnosis-to-ablation time had the strongest association with the ablation outcomes which persisted in multivariable Cox analyzes (hazard ratio for recurrence per +1Log diagnosis-to-ablation time 1.27, 95% confidence interval 1.14-1.43; P<0.0001; hazard ratio fourth versus first quartile 2.44, 95% confidence interval 1.68-3.65; P(categorical)<0.0001). CONCLUSIONS: In patients with PersAF undergoing ablation, the time interval between the first diagnosis of PersAF and the catheter ablation procedure had a strong association with the ablation outcomes, such as shorter diagnosis-to-ablation times were associated with better outcomes and in direct association with markers of atrial remodeling.

Safety of Catheter Ablation for Atrial Fibrillation in Patients With Prior Cerebrovascular Events.

OBJECTIVES: This study sought to report on the safety of catheter ablation for atrial fibrillation (AF) in patients with prior cerebrovascular events (CVEs), at a large-volume tertiary care center over the course of the past 15 years. BACKGROUND: Many patients with drug-refractory AF have a history of a prior CVE. These patients are considered to be at high procedural risk for catheter ablation but data are scant. METHODS: All consecutive patients undergoing AF ablation at the Cleveland Clinic were enrolled in a prospectively maintained data registry, which was used to identify patients with a prior CVE. Strict periprocedural anticoagulation protocols were in place. Extreme care was taken with sheath and catheter manipulation to prevent thrombus formation or air embolism. All thromboembolic and hemorrhagic events occurring periprocedurally and up to 3 months of follow-up were identified. RESULTS: Of 9,413 consecutive patients who underwent AF ablation, 247 patients with a prior CVE were identified (median age, 64 years; 40.1% female; median CHA2DS2-VASC score, 4). Anticoagulants used were warfarin (n = 192), dabigatran (n = 32), rivaroxaban (n = 15), and apixaban (n = 8). All patients received intravenous heparin before transseptal access (activated clotting time target during procedure, 350 to 400 seconds). The energy source was radiofrequency in 242 patients and cryoenergy in 5 patients. Acute procedural complications included 5 groin hematomas (1 requiring transfusion), 5 pericardial effusions with associated tamponade physiology in 2 (1 required pericardiocenthesis, 1 required surgery), and 1 arteriovenous fistula (managed conservatively). Importantly, none of the patients had a periprocedural thromboembolic event. CONCLUSIONS: Patients with a prior history of cerebrovascular events do not seem to be predisposed to a significant risk of clinical CVE recurrence when undergoing catheter ablation for AF without interruption of therapeutic anticoagulation.

Long-term outcomes in patients with ambulatory new york heart association class III and IV heart failure undergoing cardiac resynchronization therapy.

Patients with ambulatory New York Heart Association (NYHA) class IV heart failure were significantly underrepresented in clinical trials of cardiac resynchronization therapy (CRT). The natural long-term trajectory of survival free of left ventricular assist device (LVAD) or heart transplant in patients with ambulatory class IV symptoms who underwent CRT has not been established. We extracted clinical data on 723 consecutive patients with NYHA class III or ambulatory class IV heart failure, left ventricular ejection fraction ≤35%, and a QRS duration ≥120 ms who underwent CRT from September 30, 2003, to August 6, 2007. Chart notes immediately before CRT were reviewed to confirm NYHA class status before CRT. Kaplan-Meier curves and a multivariate Cox proportional hazards model were constructed to determine long-term survival free of heart transplant and LVAD based on NYHA class status. Of the 723 patients, 52 had ambulatory class IV symptoms. Over a mean follow-up of 5.0 ± 2.5 years controlling for many possible confounders, ambulatory NYHA class IV status was independently associated with poor long-term outcomes. The 1-, 2-, 3-, 4-, and 5-year survival free of LVAD or heart transplant for class III versus ambulatory class IV patients was 92.0%, 84.0%, 75.0%, 68.1%, and 63.2% versus 75.0%, 61.5%, 52.0%, 45%, and 40.4%, respectively. Although patients with ambulatory class IV heart failure receiving CRT have inferior long-term outcomes compared with those with class III symptoms, survival in class IV patients continues to parallel class III patients over an extended follow-up. At 5 years, survival free of LVAD or heart transplant in ambulatory class IV patients receiving CRT is 40%.

Percutaneous extraction of stented device leads.

BACKGROUND: There are limited published data regarding the percutaneous extraction of device leads jailed by a venous stent. OBJECTIVE: In this study we assessed the feasibility and safety of percutaneous extraction of stented device leads. METHODS: We reviewed our experience percutaneously extracting 7 chronically implanted device leads jailed to the wall of the left innominate and/or subclavian veins by a previously placed stent. RESULTS: All leads were successfully extracted by using a percutaneous approach. Both pacing leads and defibrillator leads were extracted. The oldest pacing lead extracted was 14 years old. The oldest defibrillator lead extracted was 6 years old. Three of the leads were extracted with simple manual traction alone. The 4 remaining leads required a more complex, femoral extraction approach for successful removal. CONCLUSION: In our experience extracting 7 stented device leads, complete percutaneous removal was feasible 100% of the time using a combination of simple manual traction and a femoral approach. No major complications were associated with the extraction procedures.

Omega-3 fatty acids, vitamin C and Zn supplementation in asthmatic children: a randomized self-controlled study.

OBJECTIVES: Bronchial asthma is a chronic inflammatory airways disease. Nutritional intervention is an important tool to decrease the severity of many chronic inflammatory diseases including asthma. The aim of this study is to evaluate the role of omega-3 fatty acids, vitamin C and Zn in children with moderately persistent asthma. PATIENTS AND METHODS: Randomly assigned, placebo-self-controlled 60 children with moderate persistent asthma completed the study, were subjected to alternating phases of supplementation with omega-3 fatty acids, vitamin C and Zn either singly or in combination separated with washout phases. Childhood asthma control test (C-ACT), pulmonary function tests and sputum inflammatory markers were evaluated at the beginning of the study and at the end of each therapeutic phase. RESULTS: There was a significant improvement of C-ACT, pulmonary function tests and sputum inflammatory markers with diet supplementation with omega-3 fatty acids, vitamin C and Zn (p < 0.001*). There was also significant improvement with the combined use of the three supplementations than single use of any one of them (p < 0.001*). CONCLUSION: Diet supplementation with omega-3 fatty acids, Zn and vitamin C significantly improved asthma control test, pulmonary function tests and pulmonary inflammatory markers in children with moderately persistent bronchial asthma either singly or in combination.

HLA in Egyptian children with biliary atresia.

We studied the human leukocytes antigens in 18 Egyptian children with biliary atresia (BA) without extrahepatic congenital malformations. There was a significant increased frequency of both B8 and DR3 (83.3% and 94.4% in patients with BA compared with 6.5% and 14.9% in the general population, respectively). Ten patients had the B8/DR3 haplotype. Our results support the hypothesis that genetic factors may play a role in susceptibility to BA.