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Background: Preliminary reports have suggested the role of annular calcium in independently predicting pacemaker implantation after transcatheter aortic valve replacement (TAVR). Data regarding role of calcium in the aortic-valvular complex on pacemaker dependency is lacking. Hypothesis: Calcium volume and score in the aortic annular region predicts RV (right ventricle) pacing burden. Methods: We conducted a retrospective single-center study at our tertiary care center including patients who had new pacemaker implantation after TAVR procedure (n=47). Standard calcium scoring software was used to demarcate and quantify the calcium along the aortic cusps and subvalvular region and dichotomized into septal and non-septal based on proximity to the interventricular septum. Standard statistical tests were used for analysis with two-sided p-value Results: The mean age was 78.6 ± 10.3 years and females were 42.6%. At baseline, 44.7% had narrow QRS complex, with 31.9% had right bundle branch block (RBBB), 8.5% had left bundle branch block (LBBB). Median Pre-TAVR QRS duration was 112 ms. Median septal and non-septal calcium score were 646 and 474 with a volume of 441 mm 3 and 327.2 mm 3 , respectively. Patients with progression to complete heart block (CHB) during index admission had significantly higher non-septal volume (650 mm 3 vs 344 mm 3 ;p=0.01) and score (892 vs 485;p=0.01) when compared to progression after discharge. Similarly, the high burden of RV pacing (>40%) was associated with lower septal calcium score (989 vs 552, p= 0.03) and volume (717 mm 3 vs 385 mm 3 , p=0.03) within 3 months of TAVR. No septal or non-septal parameters were predictive of pacing burden for mid-term (3-12 months) and long-term (>12 months) follow up. Septal calcium parameters were not predictive of RV pacing burden or progression to CHB. Conclusion: Quantitative calcium in the non-septal and septal regions were predictive of early progression to CHB and a higher burden of RV pacing, respectively. Larger scale studies on calcium distribution and the burden should be performed to validate our findings.

Introduction: The Emory risk score has been developed to predict new pacemaker implantation in patients undergoing TAVR procedures. There is limited data on assessing risk of early versus late pacemaker implantation in these patients. Hypothesis: The Emory risk score is similar for patients with both early and late pacemaker implantation in TAVR patients. Methods: A single center observational study was performed at our tertiary care center. All patients who underwent pacemaker implantation after TAVR procedures were included. Patients were categorized as early or late if they had pacemaker implantation within the same admission versus implantation post discharge. Standard statistical tests were used for analysis with two-sided p value Results: A total of 97 patients were studied between January 2017 to April 2020. The mean age was 77.5 ± 7 years and females were 41.2%. At baseline patients with early implantation of pacemakers (n=66) had a higher proportion of underlying RBBB (45.2% vs 23.3%, p=0.43), higher valve size as well as a higher incidence of valve oversizing > 146% (43.9 % vs 19.4 %, p =0.23)when compared to patients with late pacemakers(n=31). There was no difference between patient characteristics, baseline comorbidities, pre procedural ECG parameters as well as use of beta blocking agents. Late pacemaker implantations were associated with a overall lower Emory Risk score (1.06±1.41 vs 1.70±1.35, p =0.037). Conclusions: The Emory Risk score is significantly different for early and late pacemaker implantation. Further studies are needed evaluate risk of late pacemaker implantation.

Introduction: Cardiac resynchronization therapy (CRT) upgrade is indicated for improvement of cardiac function in patients with chronic right ventricular (RV) pacing burden >40% and heart failure with reduced ejection fraction. It is uncertain whether the CRT response is different among patients with high (≥90%) versus intermediate ( Hypothesis: To assess the impact of baseline RV pacing percent on ECG and echocardiographic response after CRT upgrade for pacing induced cardiomyopathy. Methods: We conducted a retrospective study of all CRT upgrades for pacing induced cardiomyopathy at our hospital from January 2017 to December 2018. Cohorts were grouped by RV pacing burden ≥90% or Results: We included 82 patients (age 74 ± 12 yr., 71% male) who underwent CRT upgrade for pacing induced cardiomyopathy. The RV pacing burden was ≥90% [median 99% (IQR 98-99%)] in 61 patients, and Conclusions: A higher baseline RV pacing burden predicts a greater improvement in LVEF after CRT upgrade for pacing induced cardiomyopathy.

In the recently published review “Techniques to Avoid Complications of Atrial Fibrillation Ablation,” the following author name was inadvertently misspelled as Amit Shreshta.

Dofetilide is a class III antiarrhythmic drug that has been reported to be safe and efficacious in the treatment of atrial dysrhythmias with a known initial risk of QT prolongation and torsades de pointes (TdP). As a result, the Federal Drug Administration (FDA) mandated in-hospital dofetilide initiation and adherence to a common dosing protocol. However, there is a lack of clarity on how to manage dofetilide re-initiation.An observational survey was performed including 347 cardiologists in the United States and worldwide to evaluate the deviations from approved manufacturer's protocol during dofetilide initiation and re-initiation among practicing cardiologists.Most practicing cardiologists were cautious about outpatient dofetilide use and adhered to the manufacturer's in-patient dofetilide protocol during de-novo initiation and reported low incidence of TdP in clinical practice. There were substantial differences among practicing cardiologists with deviation from the manufacturer's protocol during re-initiation of dofetilide. About 21% cardiologists always admitted patients to the hospital while 37% admitted patients10% of the time for dofetilide re-initiation. Only 4% reported major adverse events with outpatient dofetilide re-initiation. There was also wide variation regarding monitoring of electrolytes and QT interval as an outpatient with dofetilide.There is significant practice pattern variation in the use of dofetilide for the management of AF. This degree of variation noted is concerning and is a reflection of the current lack of substantial clinical evidence in the re-initiation dofetilide protocol to help direct the provider.

Anomalous Coronary Artery arising from Opposite Sinus (ACAOS) is rare anomaly which does not generally lead to heart block & PSVT A 47 years old active, healthy woman presented with dyspnea on exertion & palpitations. On long term cardiac monitor, she had multiple episodes of high-grade AV block

ObjectivesThis study sought to examine whether suppressing premature ventricular contractions (PVC) using radiofrequency ablation improves effectiveness of the cardiac resynchronization therapy (CRT) in nonresponders.BackgroundCRT is an effective strategy for drug refractory congestive heart failure. However, one-third of patients with CRT do not respond clinically, and the causes for nonresponse are poorly understood. Whether frequent PVC contribute to CRT nonresponse remains unknown.MethodsIn this multicenter study, CRT nonresponders with >10,000 PVC in 24 h who underwent PVC ablation were enrolled from a prospective database.ResultsSixty-five subjects (age 66.6 ± 12.4 years, 78% men, QRS duration of 155 ± 18 ms) had radiofrequency ablation of PVC from 76 foci. Acute and long-term success rates of ablation were 91% and 88% in 12 ± 4 months of follow-up. There was significant improvement in left ventricular (LV) ejection fraction (26.2 ± 5.5% to 32.7 ± 6.7 %, p < 0.001), LV end-systolic diameter (5.93 ± 0.55 cm to 5.62 ± 0.32 cm, p < 0.001), LV end-diastolic diameter (6.83 ± 0.83 cm to 6.51 ± 0.91 cm, p < 0.001), LV end-systolic volume (178 ± 72 to 145 ± 23 ml, p < 0.001), LV end-diastolic volume (242 ± 85 ml to 212 ± 63 ml, p < 0.001), and median New York Heart Association functional class (3.0 to 2.0, p < 0.001). Modeling of pre-ablation PVC burden revealed an improvement in ejection fraction when the pre-ablation PVC burden was >22% in 24 h.ConclusionsFrequent PVC is an uncommon yet significant cause of CRT nonresponse. Radiofrequency ablation of PVC foci improves LV function and New York Heart Association class and promotes reverse remodeling in CRT nonresponders. PVC ablation may be used to enhance CRT efficacy in nonresponders with significant PVC burden.

Patients with prosthetic valves have a high prevalence of atrial fibrillation (AF). We report a multicenter experience of performing pulmonary vein antral isolation (PVAI) in this challenging, high-risk cohort of patients.The purpose of this study was to assess the feasibility, safety, and efficacy of radiofrequency (RF) ablation for sinus rhythm restoration in AF patients with mitral or aortic mechanical prosthetic valves.A total of 50 patients with prosthetic valves (group I) who underwent RF ablation for AF between January 1, 2007, and April 30, 2009, were identified prospectively at four tertiary care centers. A matched group of 50 patients (group II) acted as controls.Total procedural time (199.4 ± 49 minutes vs 166.6 ± 27.5 minutes, P.001) and fluoroscopy time (60 ± 17 minutes vs 53.8 ± 6.8 minutes, P.01) were prolonged, with a higher incidence of atrial flutter at 3 months in group I (18% vs 6%, P = .1) compared to group II. At 12 months, 80% of patients in the valve group were in sinus rhythm after an average of 1.3 procedures, and 82% of controls were in sinus rhythm after an average 1.2 procedures (P = .9). There was a trend toward a higher nonfatal complication rate in the valve group than in the control group (8% vs 4%, P = .1).In patients with prosthetic valves, RF ablation for AF is feasible, safe, and efficacious, with a trend toward a higher nonfatal complication rate and an increased rate of postablation atrial flutter.

Patients presenting with frequent ventricular arrhythmias can have underlying myocardial inflammation as an inciting factor. We seek to determine whether the site of origin (SOO) of ventricular arrhythmias on 12 lead EKG correlate with areas of inflammation on FDG PET cardiac imaging in patients

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.

This study addressed whether cardiac sympathetic denervation progresses over time in Parkinson's disease. In 9 patients without orthostatic hypotension, 6-[(18)F]fluorodopamine positron emission tomography scanning was repeated after a mean of 2 years from the first scan. 6-[(18)F]fluorodopamine-derived radioactivity was less in the second scan than in the first scan, by 31% in the left ventricular free wall and 16% in the septum. In Parkinson's disease, loss of cardiac sympathetic denervation progresses in a pattern of loss suggesting a dying-back mechanism.

Background: Patients with PD often have signs or symptoms of autonomic failure, including orthostatic hypotension. Cardiac sympathetic denervation occurs frequently in PD, but this has been thought to occur independently of autonomic failure.Methods: Forty-one patients with PD (18 with and 23 without orthostatic hypotension) and 16 age-matched healthy volunteers underwent PET scanning to visualize sympathetic innervation after injection of 6-[18F]fluorodopamine. Beat-to-beat blood pressure responses to the Valsalva maneuver were used to identify sympathetic neurocirculatory failure and plasma norepinephrine to indicate overall sympathetic innervation.Results: All patients with PD and orthostatic hypotension had abnormal blood pressure responses to the Valsalva maneuver and septal and lateral ventricular myocardial concentrations of 6-[18F]fluorodopamine-derived radioactivity >2 SD below the normal mean. In contrast, only 6 of the 23 patients without orthostatic hypotension had abnormal Valsalva responses (p < 0.0001 compared with patients with orthostatic hypotension), and only 11 had diffusely decreased 6-[18F]fluorodopamine-derived radioactivity in the left ventricular myocardium (p = 0.0004). Of the 12 remaining patients without orthostatic hypotension, 7 had locally decreased myocardial radioactivity. Supine plasma norepinephrine was lower in patients with than in those without orthostatic hypotension (1.40 ± 0.15 vs 2.32 ± 0.26 nmol/L, p = 0.005). 6-[18F]fluorodopamine-derived radioactivity was less not only in the myocardium but also in the thyroid and renal cortex of patients with PD than in healthy control subjects.Conclusions: In PD, orthostatic hypotension reflects sympathetic neurocirculatory failure from generalized sympathetic denervation.

Background: Rapid and significant rise in esophageal temperature (ET) during radiofrequency ablation (RFA) for atrial fibrillation (AF) can be an indicator of an esophageal injury and limits our ability to achieve pulmonary vein isolation(PVI) by incomplete left atrial posterior wall (PW)ablation.

Importance Significant differences have been described between women and men regarding presentation, mechanism, and treatment outcome of certain arrhythmias. Previous studies of ventricular tachycardia (VT) ablation have not included sufficient women for meaningful comparison. Objective To compare outcomes between women and men with structural heart disease undergoing VT ablation. Design, Setting, and Participants Investigator-initiated, multicenter, observational study performed between 2002 and 2013, conducted by the International VT Ablation Center Collaborative Group, consisting of 12 high-volume ablation centers. Consecutive patients with structural heart disease undergoing VT ablation were studied. Structural heart disease was defined as left ventricular ejection fraction less than 55%, hypertrophic cardiomyopathy, or right ventricular cardiomyopathy, with scar confirmed during electroanatomic mapping. Exposures Catheter ablation. Main Outcomes and Measures Ventricular tachycardia–free survival and transplant-free survival were compared between women and men. Cox proportional hazard modeling was performed. Results Of 2062 patients undergoing ablation, 266 (12.9%) were women. Mean (SD) age was 62.4 (13.3) years and 1095 (53.1%) had ischemic cardiomyopathy. Compared with men, women were younger, with higher left ventricular ejection fraction and less VT storm. Despite this, women had higher rates of 1-year VT recurrence following ablation (30.5% vs 25.3%; P = .03). This difference was only partially explained by higher prevalence of nonischemic cardiomyopathy among women and was actually most pronounced among those with ischemic cardiomyopathy. Conclusions and Relevance In 12 high-volume ablation centers, women with structural heart disease have worse VT-free survival following ablation than men. Whether this is owing to differences in referral pattern, arrhythmia substrate, or undertreatment requires further study.

To evaluate the real-world practice patterns of utilization of dofetilide for treating Atrial Fibrillation (AF). We performed an online survey of cardiologists and cardiac electrophysiologists in US and Europe. Participation was voluntary. 31 specific questions were included in the study, primarily

We intended to evaluate the incidence of electrical and mechanical failure of QuickSite (QS) and QuickFlex (QF) left ventricular (LV) leads which are a part of a lead advisory. We invited all 154 alive patients who had the QS and QF leads implanted at our center to participate in this prospective

Pulmonary hypertension is associated with significant changes in the right heart. The safety of performing Implantable Cardiac Defibrillator (ICD) implantation in these patients is not well evaluated. We performed a retrospective analysis of all consecutive patients who had a clinical diagnosis of

There is limited data on the impact of very low left ventricular ejection fraction (LVEF) on mortality after catheter ablation of ventricular tachycardia (VT). Multicenter, retrospective analysis of all consecutive patients undergoing VT ablation at 4 high volume centers between 2007 and 2010. We

Induced external hypothermia during ventricular fibrillation (VF) improves resuscitation outcomes. Our objectives were twofold (1) to determine if very rapid hypothermia could be achieved by intrapulmonary administration of cold perfluorocarbons (PFC), thereby using the lungs as a vehicle for targeted cardiopulmonary hypothermia, and (2) to determine if this improved resuscitation success.Part 1: Nine female swine underwent static intrapulmonary instillation of cold perfluorocarbons (PFC) during electrically induced VF. Part 2: Thirty-three female swine in VF were immediately ventilated via total liquid ventilation (TLV) with pre-oxygenated cold PFC (-15 degrees C) or warm PFC (33 degrees C), while control swine received no ventilation during VF. All swine in both Parts 1 and 2 underwent VF arrest for 11 min, then defibrillation, ventilation and closed chest massage until resumption of spontaneous circulation (ROSC). The endpoint was continued spontaneous circulation for 1h without pharmacologic support.Static intrapulmonary instillation of cold PFC achieved rapid cardiopulmonary hypothermia; pulmonary artery (PA) temperature of 33.5+/-0.2 degrees C was achieved by 10 min. Nine of 9 achieved ROSC. Hypothermia was achieved faster using TLV: at 6 min VF, cold TLV temperature was 32.9+/-0.4 degrees C vs. cold static instillation temperature 34.3+/-0.2 degrees C. Nine of 11 cold TLV swine achieved ROSC for 1h vs. 3 of 11 control swine (p=0.03). Warm PFC also appeared to be beneficial, with a trend toward greater achievement of ROSC than control (ROSC; warm PFC 8 of 11 vs. control 3 of 11, p=0.09).Targeted cardiopulmonary intra-arrest moderate hypothermia was achieved rapidly by static intrapulmonary administration of cold PFC and more rapidly by total liquid ventilation with cold PFC; resumption of spontaneous circulation was facilitated. Warm PFC showed a trend toward facilitating ROSC.

Background: Depolarization of myocytes requires less energy when electrical current flows along the longitudinal axis compared to the transverse axis of myocytes. Since ventricular fibrillation (VF) amplitude in ECG leads reflects the functional electrical orientation of the majority of myocytes, we hypothesized that a defibrillation shock would be more effective if the shock vector was oriented along the functional electrical axis of the majority of myocytes, and this axis could be determined in real time from the relative amplitudes of the VF signal measured in three orthogonal ECG leads. Methods: In closed-chest, anesthetized, swine (22.0 ± SE0.8 kg, n=9), a new directional defibrillation device was used to simultaneously measure the VF amplitude through three orthogonal pairs of defibrillation electrodes: anterior-posterior, lateral-lateral, and superior-inferior. VF was electrically induced and persisted for 15 seconds. During defibrillation, the device identified the electrode pair that measured the largest or smallest peak amplitudes (+ or −) within the previous 100msec through which to deliver the shock. Defibrillation success for the electrodes measuring the largest or smallest VF amplitude was evaluated by delivering four 50J shocks for VF through each of these electrode pairs (in random order). The electrode pair measuring the largest VF signal amplitude was considered to be most closely aligned with the functional VF vector. Results: Fifty J shocks (n=37) delivered through the electrode pair measuring the largest VF signal amplitude had higher defibrillation success than 50J shocks (n=37) delivered through the electrodes measuring the smallest VF signal amplitude (62 ± 10% vs.19 ± 8%, p Conclusions: By using a directional defibrillation device which instantaneously measures the peak VF signal amplitude in three pairs of orthogonally oriented defibrillation electrodes, it is feasible to determine which set of electrodes is oriented more favorably to the functional VF vector and to direct the shock through that set of electrodes. Matching the defibrillation vector to the fibrillation vector improves shock success.

Neurocardiogenic syncope is the most common cause of acute loss of consciousness in adults. The present study attempted to identify neuroendocrine and hemodynamic changes before syncope that could therefore play a pathophysiologic role. Twenty-five patients referred for chronic orthostatic intolerance had plasma catecholamines measured serially; 21 patients during tilt-table testing (evoking syncope in 13) and 4 others with spontaneous syncope while supine. Forearm blood flow was measured by impedance plethysmography. All 12 patients with blood sampled before tilt-induced syncope had progressive, marked increases in plasma epinephrine levels (mean 11 times baseline, p

A correct electrocardiographic diagnosis of the mechanism of a wide complex tachycardia (WCT) is important when instituting emergent therapy and for long-term prognostic and therapeutic considerations. While any algorithm has the risk of oversimplifying a complex problem, it is absolutely essential to have an initial strategy for the acute evaluation of an arrhythmia. Causes of wide QRS tachycardia include (1) supraventricular tachycardia (SVT) with pre-existing or functional bundle branch block, including sinus tachycardia, atrial tachycardia, atrial flutter, atrial fibrillation (AF) and AV nodal re-entry tachycardia, (2) orthodromic circus movement tachycardia with pre-existing or functional bundle branch block, (3) SVT with conduction over an accessory pathway, (4) Antidromic circus movement tachycardia using an accessory pathway in the anterograde direction and AV node in the retrograde direction, (5) ventricular tachycardia, and (6) ventricular paced rhythm. Ventricular tachycardia is by far the commonest underlying mechanism of WCT.1 The overall goal of any algorithm is to make things simpler yet effective. Most criteria are based on QRS complex duration, QRS axis, concordant pattern, presence of Q-waves, AV dissociation, fusion beats, absence of precordial RS complex, QRS alternans, and presence of multiple wide complex morphologies. Starting in 1978, several criteria have been developed to aid in the diagnosis of WCT. For evaluation of RBBB morphology tachycardias,Wellens et al .2 proposed (1) duration of QRS > 140 ms, (2) left-axis deviation, (3) certain configurational characteristics of QRS, and (4) atrioventricular (A-V) dissociation as the criteria for … *Corresponding author. Tel: +1 617 632 7393; fax: +1 617 632 7620. E-mail address : mjoseph2{at}caregroup.harvard.edu

Limited data is available on the role of percutaneous left ventricular assist devices (pLVADs) during ablation of unstable VT. Multicenter observational study of all consecutive pts undergoing VT ablation with either intra aortic balloon pump (IABP) or pLVAD. We compared the baseline

Dofetilide is one of the most effective anti-arrhythmic agents for Atrial Fibrillation (AF). Reverse Use Dependence (RUD) property of Dofetilide improves antiarrhythmic efficacy at lower heart rate. Several patients with AF have pacemakers or defibrillators for various reasons. The effectiveness of

AV nodal (AVN) ablation is sometimes needed to control ventricular rate and/or to optimize biventricular pacing (BiVP) in patients with atrial tachyarrhythmias (ATa). Limited data is available on the predictors of failure of AV nodal ablation. We performed a retrospective study including all