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Introduction Prospective studies on rivaroxaban and apixaban have shown the safety and efficacy of direct anticoagulation agents (DOAC)s used peri-procedurally during radiofrequency ablation (RFA) of atrial fibrillation (AF). Studies comparing the two agents have not been performed. Methods Consecutive patients from a prospective registry who underwent RFA of AF between April 2012 and March 2015 and were on apixaban or rivaroxaban were studied. Clinical variables and outcomes were noted. Results There were a total of 358 patients (n = 56 on apixaban and n = 302 on rivaroxaban). There were no differences in baseline characteristics between both groups. The last dose of rivaroxaban was administered the night before the procedure in 96% of patients. In patients on apixaban, 48% of patients whose procedure was in the afternoon took the medication on the morning of the procedure. TIA/CVA occurred in 2 patients (0.6%) in rivaroxaban group with none in apixaban group (p = 0.4). There was no difference in the rate of pericardial effusion between apixaban and rivaroxaban groups [1.7% vs 0.6% (p = 0.4)]. Five percent of patients in both groups had groin complications (p = 0.9). In apixaban group, all groin complications were small hematomas except one patient who had a pseudoaneurysm (1.6%). One pseudo-aneurysm, 1 fistula and 3 large hematomas were noted in patients on rivaroxaban (1.7%) with the rest being small hematomas. DOACs were restarted post procedure typically 4 h post hemostasis. Conclusions Peri-procedural uninterrupted use of apixaban and rivaroxaban during AF RFA is safe and there are no major differences between both groups.

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: Subcutaneous ICD (S-ICD) implantation is a viable alternative to transvenous ICD implantation in patients without a pacing indication. The S-ICD lead is placed near the sternum. The safety of S-ICD implantation and risk for inappropriate shocks is uncertain in patients with prior sternotomy. Methods: This single-center retrospective cohort study included patients that had implantation of an S-ICD between February 2014 - May 2020. The 30-day complication rates and long-term risks of inappropriate shocks were compared between patients with and without prior sternotomy. Results: Ninety-eight patients (52 ± 15 years old, 43% men, BMI 29 ± 6, 72% primary prevention, 28% ischemic cardiomyopathy, median LVEF 30% (IQR 25-45%)) underwent S-ICD implantation, among whom 19 (19.4%) had a prior sternotomy. The median time between sternotomy and S-ICD implantation was 96 (IQR 4.1-306) months. The sternal coil was primarily implanted left of the sternum (n=17/19, 89%). A two-incision technique was used in 79% of patients with prior sternotomy vs. 65% without sternotomy (p=0.23). The 30-day complication rate was similar between those with and without prior sternotomy (n=1/19 vs. n=10/79, 5% vs. 13%, p=0.36). The only 30-day complication in patients with prior sternotomy was a hematoma without intervention. The 30-day complications in patients without prior sternotomy included: superficial site infection resolving with brief antibiotics (n=4), inappropriate shock (n=3), lead migration requiring revision (n=2), and a hematoma without intervention (n=1). Over a median follow-up of 17.1 (IQR 3.4-29.1) months, the frequency of inappropriate shocks was similar between patients with and without prior sternotomy (n=1/19 and n=6/79, 5% vs. 8%, p=0.72). The median time to inappropriate shock from S-ICD implantation was 1.1 (IQR 0.1-19.8) months. The mechanisms of inappropriate shocks were T-wave oversensing or other oversensing (n=5/7, 72%), air in the pocket (n=1/7, 14%), and atrial tachycardia (n=1/7, 14%). Conclusions: Implantation of S-ICD in patients with prior sternotomy was not associated with an increased risk of 30-day complications or inappropriate shocks. These outcomes need to be confirmed in larger, multicenter studies.

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.

Atrial fibrillation ablation is an increasingly common procedure adapted by electrophysiologists across the world. Any procedure naturally comes with inherent risks of complications. The goal of this review is to elaborate latest techniques and strategies to avoid complications of ablation. There is increased focus on new tools for avoiding esophageal injury as well as minimizing phrenic nerve injury in addition to utilization of newer ablation technologies to address safer and effective ablation. A combination of improved patient selection and better treatment protocols combined with methods for early detection of complications will significantly reduce the incidence of complications. Newer innovative technologies like esophageal temperature monitoring, mechanical deviation, and integration of ablation parameters are helping to avoid or minimize collateral damage.

INTRODUCTION Ultrasound guided axillary vein access (UGAVA) is an emerging approach for cardiac implantable electronic device (CIED) implantation not widely utilized. METHODS AND RESULTS This is a retrospective, age and sex-matched cohort study of CIED implantation from January 2017 to July 2019 comparing UGAVA before incision to venous access obtained after incision without ultrasound (conventional). The study population included 561 patients (187 with attempted UGAVA, 68 ± 13 years old, 43% women, body mass index (BMI) 30 ± 8 kg/m2 , 15% right-sided, 43% implantable cardioverter-defibrillator, 15% upgrades). UGAVA was successful in 178/187 patients (95%). In nine patients where UGAVA was abandoned, the vein was too deep for access before incision. BMI was higher in abandoned patients than successful UGAVA (38 ± 6 vs. 28 ± 6 kg/m2 , p

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

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.

Abandoned and epicardial leads from cardiovascular implantable electronic devices (CIED) remains a contraindication to magnetic resonance imaging (MRI) studies due to previous in vitro data showing lead heating and a theoretical concern for device malfunction. We postulated that a MRI in patients

Ultrasound (US) guided axillary vein access (UGAVA) is an emerging approach to venous access for cardiac device implantation. Although US guidance is commonly utilized for central venous catheter placement, it is utilized less frequently for the implantation of cardiac devices. There is limited

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.

Background The fibrous capsule around cardiac implantable device generators is known to promote bacterial colonization and latent infection. Removal of the capsule during device replacement procedures may reduce infection rates but may increase hemorrhagic complications. Objective The purpose of this study was to evaluate the effect of pocket capsule decortication procedure on infection and bleeding rates in patients undergoing device replacement procedures. Methods In a prospective randomized single-blind control study, patients undergoing device replacement, upgrade, or lead extraction were randomized to Group A "with pocket revision" (n = 131) and group B "without pocket revision" (n = 127). Deep and superficial infection rates, bleeding, and prolonged serous drainage were assessed during 12 months of follow-up. Data were analyzed according to intention-to-treat principle. Results A total of 258 patients were enrolled in the study. Rates of generator change, upgrade, and lead extraction/replacement were similar between both groups. There was no incidence of deep infection in either group at 12-month follow-up. There was no significant difference in the incidence of superficial infection between groups (1.5% vs 4.7%, P = .13) during 12-month follow-up. There was a significant increase in acute hematoma formation in group A compared to group B (6.1% vs 0.8%, P = .03). Two patients in group A had to undergo hematoma evacuation. Conclusion There was increased incidence of hematoma formation in group A with no effect on infection rates. Our study suggests that there is no benefit to performing empiric pocket revision.

Background Despite ACC/AHA guidelines indicating implantable cardioverter defibrillator (ICD) as class I therapy for primary prevention of sudden cardiac death in patients with EF≤35%, ICD utilization rates in real world practice have been low. Objective To determine the rate of ICD implantation at a tertiary care academic center and to assess the reasons for under-utilization of the same. Methods Review of a prospectively collected database which included all patients diagnosed with an EF≤35% was performed to assess the rate of ICD implantation and mortality. Reasons for non-implantation of ICD were then assessed from detailed chart review. Results A total of 707 patients (age 69.4 ± 14.1 years) with mean EF of 26±7% were analyzed. Only 28% (200/707) of patients had ICDs implanted. Mortality was lower in the group with ICD (25% vs 37%, p=0.004). When patients who either died or were lost to follow-up prior to 2005 were excluded, ICD utilization rate was still low at 37.6%. The most common reason for non-implantation of ICD was physicians not discussing this option with their patients. Patient refusal was the second most common reason. Conclusions ICD Implantation rates for primary prevention of SCD in patients with EF≤35% is low. Physician and patient education should be addressed to improve the utilization rates.

Background Use of corticosteroids before and after atrial fibrillation (AF) ablation can decrease acute inflammation and reduce AF recurrence. Purpose To assess the efficacy of oral prednisone in improving the outcomes of pulmonary vein isolation with radiofrequency ablation and its effect on inflammatory cytokine. Methods A total of 60 patients with paroxysmal AF undergoing radiofrequency ablation were randomized (1:1) to receive either 3 doses of 60 mg daily of oral prednisone or a placebo. Inflammatory cytokine levels (TNF-α, IL-1, IL6, IL-8) were measured at baseline, prior to ablation, immediately after ablation, and 24 hours post ablation. Patients underwent 30 day event monitoring at 3 months, 6 months and 12 months post procedure. Results Immediate post ablation levels of inflammatory cytokines were lower in the steroid group when compared to the placebo group; IL-6: 9.0 ±7 vs 15.8 ±13 p=0.031; IL-8: 10.5 ±9 vs 15.3 ±8; p=0.047 respectively. Acute PV reconnection rates during the procedure (7/23% vs 10/36%; p = 0.39), and RF ablation time (51±13 vs 56±11 min, p = 0.11) trended to be lower in the placebo group than the steroid group. There was no difference in the incidence of early recurrence of AF during the blanking period and freedom from AF off AAD at 12 months between both groups (5/17% vs 8/27%; p = 0.347 and 21/70% vs 18/60%; p=0.417 in placebo and steroid groups respectively). Conclusion Although oral corticosteroids have significant effect in lowering certain cytokines, it did not impact the clinical outcomes of AF ablation.

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.

Parkinson's disease patients frequently have symptoms and signs of autonomic nervous dysfunction that are the source of considerable disability. Recent studies have revealed that most patients with Parkinson's disease, and all with Parkinson's disease-associated orthostatic hypotension, have a loss of cardiac sympathetic innervation. Familial Parkinson's disease, caused by mutation of the gene encoding alpha-synuclein, also features orthostatic hypotension, sympathetic neurocirculatory failure and cardiac sympathetic denervation. We have recently described a whole-gene triplication of alpha-synuclein causing Lewy body parkinsonism in a large, well characterized family called the 'Iowa kindred'. Here we report the results of cardiac PET scanning using the sympathoneural imaging agent, 6-[18F]fluorodopamine in affected and unaffected members of this kindred. Four family members were studied, two with parkinsonism, one clinically normal and one with benign essential tremor alone. Both affected members had obvious loss of cardiac sympathetic innervation; the unaffected member had normal innervation, as did the member with isolated essential tremor. The results indicate that, in this family, where disease is caused by overexpression of normal alpha-synuclein, cardiac sympathetic denervation cosegregates with parkinsonism. Post-mortem studies have demonstrated synuclein-positive Lewy body formation in the brains of individuals with parkinsonism who were also in the family described here and who also carry this triplication. These results indicate that both parkinsonism and cardiac sympathetic denervation can result from an excess of normal synuclein.

In PD, orthostatic hypotension reflects sympathetic noradrenergic denervation. The authors assessed sympathetic cholinergic innervation by the quantitative sudomotor axon reflex test (QSART) in 12 patients who had sympathetic neurocirculatory failure, markedly decreased cardiac 6-[ 18 F] fluorodopamine-derived radioactivity, and subnormal plasma norepinephrine increments during standing. All 12 had normal QSART results. The sympathetic nervous system lesion in PD involves loss of postganglionic catecholaminergic but not cholinergic nerves.

Background— In postural tachycardia syndrome (POTS) and repeated neurocardiogenic presyncope (NCS), orthostatic intolerance occurs without persistent sympathetic neurocirculatory failure. Whether these conditions involve abnormal cardiac sympathetic innervation or function has been unclear. Methods and Results— Patients with POTS or NCS underwent measurements of neurochemical indices of cardiac release, reuptake, and synthesis of the sympathetic neurotransmitter norepinephrine based on entry of norepinephrine into the cardiac venous drainage (cardiac norepinephrine spillover), cardiac extraction of circulating 3 H-norepinephrine, and cardiac production of dihydroxyphenylalanine and measurement of left ventricular myocardial innervation density using 6-[ 18 F]fluorodopamine positron emission tomographic scanning. Mean cardiac norepinephrine spillover in POTS (171±30 pmol/min, N=16) was higher and in NCS (62±9 pmol/min, N=20) was lower than in a large group of healthy volunteers (102±9 pmol/min, N=52) and in a subgroup of age-matched healthy women (106±18 pmol/min, N=11). Both patient groups had normal cardiac extraction of 3 H-norepinephrine, normal cardiac production of dihydroxyphenylalanine, and normal myocardial 6-[ 18 F]fluorodopamine-derived radioactivity. Conclusions— POTS and NCS differ in tonic cardiac sympathetic function, with increased cardiac norepinephrine release in the former and decreased release in the latter. Both groups had normal values for indices of function of the cell membrane norepinephrine transporter, norepinephrine synthesis, and density of myocardial sympathetic innervation. Because POTS and NCS both include specific abnormalities of cardiac sympathetic function, both can be considered forms of dysautonomia.

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.

Background: Very recently St Jude Medical (SJM) released an advisory regarding premature battery depletion in a family of implantable cardioverter-defibrillators (ICDs) including biventricular cardiac defibrillators (CRTDs). There have been reported cases of loss of pacing and inability to

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. 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. 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

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

To evaluate the impact of pre-procedural oral prednisone on inflammatory cytokines (TNF-α, Interleukin (IL)-1, IL-6, and IL-8) levels and outcomes of atrial fibrillation (AF) ablation in patients with paroxysmal AF. A total of 60 patients with paroxysmal AF undergoing AF ablation were randomized (

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

Background Staphylococcus aureus bacteremia (SAB) is commonly associated with cardiac implantable electronic device infection (CIED-I). This usually requires explantation of the device. In cases of SAB in the presence of CIED that is not obviously infected (after examination of the pocket and transesophageal echocardiogram), decision about device removal is less clear. Predicting CIED-I in those cases would be helpful. Methods: This case-control study included all adults admitted to the University of Kansas Medical Center with SAB in the presence of a CIED between 1/1/2007 and 12/31/2012, using ICD 9 codes, CIED registry, and microbiology database. Cases had device infection evidenced by pocket infection or CIED related endocarditis; controls did not, over a 12 weeks follow up period. Clinical predictors of CIED-I were evaluated using logistic regression. Mortality was evaluated at 30 and 365 days. Results: We identified 64 patients with CIED who had 70 separate episodes of SAB during the study period. Of all 70 episodes of SAB, 74.3% were in males, 74.3% were in white, and mean age was 65.3 years. MRSA accounted for 48.6% of SAB. There were 31 episodes involving the device (44.3%, cases) and 39 SAB without CIED-I (55.7%, controls). On univariate analysis, factors associated with increased risk of device infection included fever (Odds ratio [OR] 5.65, 95% confidence interval [CI] [1.45-22.04], pvalue 0.011), persistent bacteremia at 72h (OR 2.89, CI [0.978.60], p-value 0.052), and tachycardia (OR 2.41, CI [0.827.10], p-value 0.098). Factors associated with decreased risk of device infection included end stage renal disease (ESRD) (OR 0.24, CI [0.07 0.81], p-value 0.029) and immunosuppression in the past 3 months (OR 0.23, CI [0.051.16], p-value 0.096). On multivariate analysis only fever remained significantly associated with device infection (OR 6.58, CI [1.20-36.04]). Mortality at 30 and 365 days was not significantly different between cases and controls. Conclusion: Fever, tachycardia and persistent bacteremia were associated with increased risk of CIED-I among patient with SAB, while ESRD and immunosuppression were protective on univariate analysis. Only fever remained significantly associated with CIED infection on multivariate analysis.  Retrospective review of all patients with SAB who had CIED at the same time between 1/1/2007 and 12/31/2012

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.

Combined chemotherapy and radiotherapy increase long-term survival in patients with head and neck tumors. Late complications of treatment, however, are being recognized increasingly. Surgery or radiotherapy of the carotid sinuses or brain stem can evoke labile hypertension and orthostatic intolerance from acute or subacute baroreflex failure. Here we report cases in which chronic baroreflex failure appeared to develop as a late sequela of neck irradiation. Three patients referred for autonomic nervous system function testing had labile blood pressure and chronic orthostatic intolerance that developed years after neck irradiation for cancer. In each patient, heart rate remained constant during performance of the Valsalva maneuver, suggesting baroreflex-cardiovagal failure. All 3 patients had virtually zero baroreflex-cardiovagal gain, quantified by interbeat interval–systolic blood pressure relationships after intravenous phenylephrine or nitroglycerine. Ambulatory blood pressure monitoring revealed highly variable blood pressure, with sudden pressor and depressor episodes, a characteristic feature of baroreflex failure. Cardiovagal efferent function, assessed by power spectral analysis of heart rate variability during slow, deep respiration, was normal. Sympathetic noradrenergic efferent function, assessed by cold pressor testing and plasma catecholamine levels during supine rest and orthostasis, was also normal or increased. These findings indicated a primarily afferent lesion. Carotid ultrasonography revealed intimal thickening and atheromatous plaques in all 3 patients. We propose that labile hypertension and orthostatic intolerance can develop as a late sequela of neck irradiation, due to chronic carotid baroreflex failure, which in turn is due to radiation-induced accelerated development of carotid arteriosclerosis. Splinting of carotid sinus mechanoreceptors in rigidified arterial walls would impede detection of alterations in blood pressure and thereby disrupt baroreflex regulation of cardiovagal and sympathetic outflows.

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