Asirvatham, Samuel J

Background: Heart failure with preserved ejection fraction is increasing in prevalence, but few effective treatments are available. Elevated left ventricular (LV) diastolic filling pressures represent a key therapeutic target. Pericardial restraint contributes to elevated LV end-diastolic pressure, and acute studies have shown that pericardiotomy attenuates the rise in LV end-diastolic pressure with volume loading. However, whether these acute effects are sustained chronically remains unknown. Methods: Minimally invasive pericardiotomy was performed percutaneously using a novel device in a porcine model of heart failure with preserved ejection fraction. Hemodynamics were assessed at baseline and following volume loading with pericardium intact, acutely following pericardiotomy, and then again chronically after 4 weeks. Cardiac structure was assessed by magnetic resonance imaging. Results: The increase in LV end-diastolic pressure with volume loading was mitigated by 41% (95% CI, 27%–45%, P <0.0001; ΔLV end-diastolic pressure reduced from +9±3 mm Hg to +5±3 mm Hg, P =0.0003, 95% CI, −2.2 to −5.5). The effect was sustained at 4 weeks (+5±2 mm Hg, P =0.28 versus acute). There was no statistically significant effect of pericardiotomy on ventricular remodeling compared with age-matched controls. None of the animals developed hemodynamic or pathological indicators of pericardial constriction or frank systolic dysfunction. Conclusions: The acute hemodynamic benefits of pericardiotomy are sustained for at least 4 weeks in a swine model of heart failure with preserved ejection fraction, without excessive chamber remodeling, pericarditis, or clinically significant systolic dysfunction. These data support trials evaluating minimally invasive pericardiotomy as a novel treatment for heart failure with preserved ejection fraction in humans.

This study presents gastric ablation as a new method for modulating slow wave activation and propagation in vivo, by creating localized electrical conduction blocks in the stomach, validated by high-resolution electrical mapping and histological tissue analysis. The results define the effective energy dose range for creating conduction blocks, while maintaining the mucosal and submucosal integrity, and demonstrate the electrophysiological effects of ablation. In future, gastric ablation can now be translated toward disrupting dysrhythmic slow wave activation.

Background The prognosis of left ventricular noncompaction (LVNC) remains elusive despite its recognition as a clinical entity for >30 years. We sought to identify clinical and imaging characteristics and risk factors for mortality in patients with LVNC. Methods and Results 339 adults with LVNC seen between 2000 and 2016 were identified. LVNC was defined as end‐systolic noncompacted to compacted myocardial ratio >2 (Jenni criteria) and end‐diastolic trough of trabeculation‐to‐epicardium (X):peak of trabeculation‐to‐epicardium (Y) ratio <0.5 (Chin criteria) by echocardiography; and end‐diastolic noncompacted:compacted ratio >2.3 (Petersen criteria) by magnetic resonance imaging. Median age was 47.4 years, and 46% of patients were female. Left ventricular ejection fraction <50% was present in 57% of patients and isolated apical noncompaction in 48%. During a median follow‐up of 6.3 years, 59 patients died. On multivariable Cox regression analysis, age (hazard ratio [HR] 1.04; 95% CI, 1.02–1.06), left ventricular ejection fraction <50% (HR, 2.37; 95% CI, 1.17–4.80), and noncompaction extending from the apex to the mid or basal segments (HR, 2.11; 95% CI, 1.21–3.68) were associated with all‐cause mortality. Compared with the expected survival for age‐ and sex‐matched US population, patients with LVNC had reduced overall survival ( P <0.001). However, patients with LVNC with preserved left ventricular ejection fraction and patients with isolated apical noncompaction had similar survival to the general population. Conclusions Overall survival is reduced in patients with LVNC compared with the expected survival of age‐ and sex‐matched US population. However, survival rate in those with preserved left ventricular ejection fraction and isolated apical noncompaction was comparable with that of the general population.

AbstractBackgroundLittle is known about the ablation outcomes of premature ventricular contractions (PVCs) that originate from the periprosthetic aortic valve (PPAV) regions of patients with aortic valve replacement (AVR).Methods and ResultsOur study had 11 patients who underwent catheter ablation for PVCs arising from the PPAV regions (bioprosthetic aortic valve, n = 5; mechanical aortic valve, n = 6). The PVC characteristics, procedure characteristics, and efficacy of ablation were compared with the control group (n = 33). At baseline, the PPAV group had a lower left ventricular ejection fraction (mean [SD], 41% [12%] vs. 51% [8%]; p = .002). The rate of acute ablation success was 90.9% in the PPAV group. Ablation sites were identified above the left coronary cusp (LCC) and right coronary cusp commissure (LRCC) in one PVC, below the prosthetic valve in eight PVCs (four below LCC and four below LRCC), and within the distal coronary sinus in two PVCs. The mean procedure time, fluoroscopy time, and radiation in the PPAV group were all significantly greater than those in the control group (all p < .05). However, the number of radiofrequency ablation energy deliveries was not different. The PPAV group had a long‐term success rate compared with the control group (72.7% vs. 87.9%, p = .48) and an increase of left ventricular ejection fraction from 43% to 49% after successful PVC ablation at follow‐up (p < .001). Echocardiography showed no significant change in valve regurgitation after ablation. No new atrioventricular block occurred.ConclusionPVCs arising from PPAV regions can be successfully ablated in patients with prior AVR, without damaging the prosthetic aortic valve and atrioventricular conduction.

Background: Increased parasympathetic activity is thought to play important roles in syncope events of patients with vasovagal syncope (VVS). However, direct measurements of the vagal control are difficult. The novel deceleration capacity (DC) of heart rate measure has been used to characterize the vagal modulation. This study aimed to assess vagal control in patients with VVS and evaluate the diagnostic value of the DC in VVS. Methods: Altogether, 161 consecutive patients with VVS (43±15 years; 62 males) were enrolled. Tilt table test was positive in 101 and negative in 60 patients. Sixty-five healthy subjects were enrolled as controls. DC and heart rate variability in 24-hour ECG, echocardiogram, and biochemical examinations were compared between the syncope and control groups. Results: DC was significantly higher in the syncope group than in the control group (9.6±3.3 versus 6.5±2.0 ms, P <0.001). DC was similarly increased in patients with VVS with a positive and negative tilt table test (9.7±3.5 and 9.4±2.9 ms, P =0.614). In multivariable logistic regression analyses, DC was independently associated with syncope (odds ratio=1.518 [95% CI, 1.301–1.770]; P =0.0001). For the prediction of syncope, the area under curve analysis showed similar values when comparing single DC and combined DC with other risk factors ( P =0.1147). From the receiver operator characteristic curves for syncope discrimination, the optimal cutoff value for the DC was 7.12 ms. Conclusions: DC>7.5 ms may serve as a good tool to monitor cardiac vagal activity and discriminate VVS, particularly in those with negative tilt table test.

Background: Left atrial appendage occlusion with the Watchman device is an alternative strategy for stroke risk reduction in patients with non-valvular atrial fibrillation. There are rare case reports of Watchman associated infection. Currently, there is no formal study that evaluated the incidence and outcomes of Watchman-related infections. Methods: All patients who underwent Watchman implantation over a 14 year study period (July 2004 through December 2018) comprised our cohort. Baseline characteristics, procedural data, and post-implantation events were identified. Primary study outcomes included Watchman related infection, other cardiovascular device related infection, bacteremia, and mortality. Results: A total of 181 patients with an average age of 75, and a median CHA2DS2-VASc Score of 4 (interquartile range 2) and a median HAS-BLED Score of 3 (interquartile range 1), were included for analysis. A total of 534.7 patient years of follow up was accrued with an average of 2.9 years per patient. The most common indications for implantation included gastrointestinal bleeding (56 patients; 30.9%) and intracerebral bleeding (51 patients; 28.2%). During follow up, 38 patients (21%) died. Six developed evidence of bacteremia. Only one developed an implantable cardioverter defibrillator (ICD) infection that required complete system extraction. None of the cohort developed Watchman-related device infection during the study period. Conclusion: In a single center study spanning a 14 year period, we report no Watchman-related devices infections. This is despite the presence of patients with bacteremia, as well as an ICD infection requiring extraction. These data suggest that Watchman devices are extremely unlikely to become infected.

AbstractIntroductionTherapies for substrate‐related arrhythmias include ablation or drugs targeted at altering conductive properties or disruption of slow zones in heterogeneous myocardium. Conductive compounds such as carbon nanotubes may provide a novel personalizable therapy for arrhythmia treatment by allowing tissue homogenization.MethodsA nanocellulose carbon nanotube‐conductive hydrogel was developed to have conduction properties similar to normal myocardium. Ex vivo perfused canine hearts were studied. Electroanatomic activation mapping of the epicardial surface was performed at baseline, after radiofrequency ablation, and after uniform needle injections of the conductive hydrogel through the injured tissue. Gross histology was used to assess distribution of conductive hydrogel in the tissue.ResultsThe conductive hydrogel viscosity was optimized to decrease with increasing shear rate to allow expression through a syringe. The direct current conductivity under aqueous conduction was 4.3 × 10−1 S/cm. In four canine hearts, when compared with the homogeneous baseline conduction, isochronal maps demonstrated sequential myocardial activation with a shift in direction of activation to surround the edges of the ablated region. After injection of the conductive hydrogel, isochrones demonstrated conduction through the ablated tissue with activation restored through the ablated tissue. Gross specimen examination demonstrated retention of the hydrogel within the tissue.ConclusionsThis proof‐of‐concept study demonstrates that conductive hydrogel can be injected into acutely disrupted myocardium to restore conduction. Future experiments should focus on evaluating long‐term retention and biocompatibility of the hydrogel through in vivo experimentation.

AbstractIntroductionThe need for transparency in financial relationships in the healthcare system, has culminated in Open Payments database, managed by the Center for Medicare and Medicaid Services (CMS). Since its inception in 2013, the trend in such payments to physicians practicing cardiac electrophysiology was not examined.Methods and ResultsPayment information reported to CMS from January 2013 to December 2018 was obtained from the publicly available Open Payments data set using the online query tool. The data were analyzed by an individual provider and by state. An in‐depth analysis of payments in the year 2018 payments was performed. From 2014 to 2018, there was an 18% increase in the total number of payments reported from 88 877 payments in 2014 to 105 000 in 2018. Despite the increase in the total number of payments reported, the average payment steadily decreased over time, resulting in an overall reduction in the total amount of payments from 2014 to 2018 ($34.9 million to $28.2 million). Payments to the top 5% of individual recipients have also decreased over this time. In 2018, 2888 unique providers received reportable payments, a total of 105 000 payments, with a median payment amount of $1378 (interquartile range: $165–$5781). The majority of these payments were for food and beverage (82%) and travel/lodging (10%). The top five payers include Boston Scientific, Medtronic Vascular, Abbott Laboratories, Janssen Pharmaceuticals, and Biotronik.ConclusionAmong cardiac electrophysiologists, there is increased reporting of payments in the Open Payments program over time, with a notable decrease in the payment amount.

AbstractTranscatheter mitral valve replacement (TMVR) with off‐label use of aortic balloon‐expandable transcatheter heart valves has emerged as a therapeutic option in high‐surgical risk patients with severe mitral annular calcification. Left ventricular outflow tract (LVOT) obstruction post valve deployment is a major limitation. We describe a case of septal reduction therapy using radiofrequency ablation (RFA) when established methods of septal reduction were either ineffective or not feasible. RFA permitted successful enlargement of the LVOT area and subsequent TMVR.