Citations

Background: Inability to eliminate intramural arrhythmogenic substrate may lead to recurrent ventricular tachycardia after catheter ablation. The aim of the present study was to evaluate intramural and full thickness lesion formation using a heated saline-enhanced radiofrequency (SERF) needle-tip catheter, compared with a conventional ablation catheter in normal and infarcted myocardium. Methods: Twenty-two adult mongrel dogs (30–40 kg, 15 normal and 7 myocardial infarct group) were studied. Lesions were created using the SERF catheter (40 W/50 °C) or a standard contact force (CF) catheter in both groups. Results: Comparing SERF to CF ablation, the SERF catheter produced larger lesion volumes than the standard CF catheter—even with >20 g of CF—in both normal (983.1±905.8 versus 461.9±178.3 mm 3 ; P =0.023) and infarcted left ventricular myocardium (1052.3±543.0 versus 340.3±160.5 mm 3 ; P =0.001). SERF catheter lesions were more often transmural than standard CF lesions with >20 g of CF in both groups (59.1% versus 7.7%; P <0.001 and 60.0% versus 12.5%; P =0.017, respectively). Using the SERF catheter, mean depth of ablated lesions reached 90% of the left ventricular wall in both normal and infarcted myocardium. Conclusions: The SERF catheter created more transmural and larger ablative lesions in both normal and infarcted canine myocardium. SERF ablation is a promising new approach for endocardial intramural and full thickness ablation of ventricular tachycardia substrate that is not accessible with current techniques.

Objectives: We sought to evaluate the procedural safety and outcomes of high power (HP) versus conventional power (CP) radiofrequency (RF) ablation during pulmonary vein isolation (PVI). Methods: A systematic search was used via MEDLINE, EMBASE, and Cochrane databases between 01/1998 and 05/2020 for studies comparing the safety and efficacy between HP and CP during RF ablation for PVI using contact-force catheters (ThermocoolSmartTouch or TactiCath). The search terms used were “AF” AND “catheter ablation” OR “radiofrequency ablation”. Results: From eight comparative observational studies, we developed a cohort of 992 patients (478 in the HP and 514 in the CP group). The median maximum energy output used in the HP group was 50W vs 35W in the CP group. There was a statistically significant difference noted in acute pulmonary vein reconnection (APVR) in the HP group compared to the CP groups at16% vs 32.6%, respectively (RR: 0.53, 95% CI: 0.33 - 0.86, P = 0.01). Freedom from arrhythmia at 12 months follow-up was also significant and found to be 87.8% of cases in the HP group versus75.2% of cases in the CP group (RR: 0.46, 95%CI: 0.32 - 0.65, P <0.01). The mean RF ablation time was 20.1 minutes in the HP group vs 39.6 minutes in the CP group (P <0.01). The mean total procedural time was 103.5 minutes in the HP group compared to 135 minutes in the CP group (P <0.01). Two patients in the CP group experienced severe adverse events (1 cardiac tamponade and 1 myocardial infarction). No serious AEs were found in the HP group. Non-serious AEs (groin complications, pericardial effusion, and phrenic nerve injury) were reported in 0.35% and 0.51% of cases in the HP and CP group, respectively. Conclusion: This study suggests that HP PVI ablation can be associated with better ablation outcomes by reducing the rate of acute and late PV reconnection and atrial arrhythmia recurrence, with similar safety profiles, and shorter procedural times. These findings merit evaluation in a randomized controlled trial.

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.

Background Patients with Eisenmenger syndrome are known to have a high incidence of sudden cardiac death ( SCD ), yet the underlying causes are not well understood. We sought to define the predictors of SCD in this population. Methods and Results A retrospective analysis of all patients with Eisenmenger syndrome from 2 large tertiary referral centers was performed. ECGs, prolonged ambulatory recordings, echocardiograms, and clinical histories were reviewed; and the cause of death was identified. A total of 246 patients (85 [34.6%] men) with a mean age of 37.3 (±14.2) years were followed up for a median of 7 years. Over the study period, 136 patients died, with 40 experiencing SCD and 74 experiencing cardiac death (sudden and nonsudden). Age, atrial fibrillation, prolonged QRS duration, complete heart block, right atrial enlargement, right bundle branch block, increased right atrial pressure, impaired biventricular function, and the presence of a pacemaker were associated with increased risk of SCD , whereas advanced pulmonary hypertension therapies were protective. Atrial fibrillation (11.45‐fold increased risk; P <0.001) and QRS duration ≥120 ms (2.06‐fold increased risk; P =0.034) remained significant predictors of SCD in the multivariate analysis, whereas advanced pulmonary hypertension therapies were strongly protective against SCD ( P <0.001). Conclusions Atrial arrhythmias, impaired ventricular function, and conduction system disease were associated with increased risk of SCD in this cohort of patients with Eisenmenger syndrome, providing an opportunity for early risk stratification and potential intervention. Clinical heart failure symptoms (New York Heart Association class ≥ II ) were predictive of increased mortality but not of SCD , suggesting a potential arrhythmic cause behind SCD .

AbstractBackgroundRecipients of implantable cardioverter defibrillator (ICD) generator replacement with multiple medical comorbidities may be at higher risk of adverse outcomes that attenuate the benefit of ICD replacement. The aim of this investigation was to study the association between the Charlson comorbidity index (CCI) and outcomes after ICD generator replacement.MethodsAll patients undergoing first ICD generator replacement at Mayo Clinic, Rochester and Beth Israel Deaconess Medical Center, Boston between 2001 and 2011 were identified. Outcomes included: (a) all‐cause mortality, (b) appropriate ICD therapy, and (c) death prior to appropriate therapy. Multivariable Cox regression analysis was performed to assess association between CCI and outcomes.ResultsWe identified 1421 patients with mean age of 69.6 ± 12.1 years, 81% male and median (range) CCI of 3 (0‐18). During a mean follow‐up of 3.9 ± 3 years, 52% of patients died, 30.6% experienced an appropriate therapy, and 23.6% died without experiencing an appropriate therapy. In multivariable analysis, higher CCI score was associated with increased all‐cause mortality (Hazard ratio, HR 1.10 [1.06‐1.13] per 1 point increase in CCI, P < .001), death without prior appropriate therapy (HR 1.11 [1.07‐1.15], P < .0001), but not associated with appropriate therapy (HR 1.01 [0.97‐1.05], P = .53). Patients with CCI ≥5 had an annual risk of death of 12.2% compared to 8.7% annual rate of appropriate therapy.ConclusionsCCI is predictive of mortality following ICD generator replacement. The benefit of ICD replacement in patients with CCI score ≥5 should be investigated in prospective studies.

Background: The treatment of heart failure with reduced ejection fraction has been the subject of numerous randomized controlled trials involving medications and cardiac implantable electronic device therapies. As newer effective pharmacological therapies suggest significant reductions in all-cause mortality, the role of additional device therapy in heart failure with reduced ejection fraction deserves further scrutiny. Methods: A systematic review and network meta-analysis on the effect of medication and device therapies in heart failure with reduced ejection fraction on all-cause mortality was performed. Randomized controlled trials published between January 1980 and July 2017 were identified using Medline, EMBASE, and Cochrane Controlled Register of Trials databases. Pcnetmeta package in R was used to calculate treatment arm–based estimated rates, rate ratios, and probability ranks with 95% credible intervals. Results: Combination therapy of ACE (angiotensin-converting enzyme) inhibitors or ARBs (angiotensin receptor blockers) with β-blockers (BBs) alone or in addition to implantable cardiac defibrillators or cardiac resynchronization therapy with defibrillators demonstrated a significant reduction of all-cause mortality when compared with placebo. By probability rank, implantable cardiac defibrillator+ACE inhibitor or ARB+BB+mineralocorticoid receptor antagonist, implantable cardiac defibrillator+ACE inhibitor or ARB+BB, and angiotensin receptor-neprilysin inhibitor+BB+mineralocorticoid receptor antagonist combination therapies have the highest probability of being ranked the best treatment. There was no significant difference in the rate of mortality when comparing angiotensin receptor-neprilysin inhibitor+BB+mineralocorticoid receptor antagonist to implantable cardiac defibrillator+optimal pharmacological combination therapy. Conclusions: BB and renin-angiotensin system blockers alone or in combination with defibrillator device therapy have robust evidence for a reduction in mortality compared with placebo. The comparative efficacy of pharmacological therapy with angiotensin receptor-neprilysin inhibitors and device therapy deserves further investigation.

Background Patients with tetralogy of Fallot ( TOF ) remain at risk for cardiovascular events despite successful repair. Some of the current risk stratification tools require advanced imaging and invasive studies, and hence are difficult to apply to routine patient care. A recent study showed that QRS fragmentation ( QRS ‐f) is predictive of mortality in patients with TOF. The current study aims to validate this result by assessing whether severity of QRS ‐f could predict all‐cause mortality in a different TOF population. Methods and Results The authors reviewed the Mayo Adult Congenital Heart Disease database for patients with TOF who had ECG from 1990–2017. QRS ‐f was defined as notches in QRS complex in ≥2 contiguous leads on ECG , not related to bundle branch block, and classified as none, mild (≤3 leads), moderate (4 leads), or severe (≥5 leads). Of 465 patients (age 37±14 years) in the study, QRS ‐f was present in 161 (35%): mild (n=43, 9%), moderate (n=77, 17%), and severe (n=41, 9%). There were 55 deaths (12%) during 13.6±8.2 years of follow‐up. Severity of QRS ‐f remained an independent predictor of all‐cause mortality after adjustment for other ECG parameters, patient demographics, and atrial and ventricular arrhythmia (hazard ratio, 1.74 per class; 95% confidence interval, 1.08–2.93 [ P =0.041]). Conclusions The presence of severe QRS ‐f may be used as complementary data to the usual clinical indices to determine whether interventions such as invasive electrophysiology study should be performed in patients with nonsustained ventricular tachycardia or to proceed with pulmonary valve replacement in patients with severe pulmonary regurgitation with ventricular volumes below the guideline‐directed threshold for intervention.

Background Tachyarrhythmias and bradyarrhythmias affect 20%–50% of adult patients with tetralogy of Fallot (TOF) and some of these patients will require cardiac implantable electronic devices (CIED) such as pacemaker and/or internal cardioverter defibrillator. Methods The Mayo Adult Congenital Heart Disease database was queried for patients with repaired TOF and history of CIED implantation, 1990–2017. The study objectives were: (1) determine the occurrence of device-related complications defined as lead failure, lead recall, device infection and lead thrombus; and (2) determine the occurrence and risk factors for defibrillator shock. Results There were 99 patients (age 46±14 years and 66 (66%) men) with CIED, and the CIEDs were 41 (41%) pacemakers and 73 (73%) defibrillators. Indication for defibrillator implantation was for primary prevention in 28 (38%) and secondary prevention in 45 (62%). Device-related complications occurred in 20 (20%) patients (lead failure 17, lead recall 4, device infection 12 and thrombus 3). Twenty-five per cent of all device infections occurred within 30 days from the time of device generator change. Annualised rates of appropriate and inappropriate shocks were 5.7% and 6.2%, respectively. The use of class III antiarrhythmic drug was protective against defibrillator shock. Conclusion The current study provides useful outcome data to aid patient counselling and clinical decision-making. Further studies are required to explore ways to decrease the risk of postprocedural infection after device generator change, and to determine which patients will benefit from empirical antiarrhythmic therapy as a strategy to decrease incidence of inappropriate defibrillator shock.

Background— The effectiveness of implantable cardioverter-defibrillators (ICDs) for primary prevention of sudden death in patients with an ejection fraction (EF) ≤35% and clinical heart failure is well established. However, outcomes after replacement of the ICD generator in patients with recovery of EF to >35% and no previous therapies are not well characterized. Methods and Results— Between 2001 and 2011, generator replacement was performed at 2 tertiary medical centers in 253 patients (mean age, 68.3±12.7 years; 82% men) who had previously undergone ICD placement for primary prevention but subsequently never received appropriate ICD therapy. EF had recovered to >35% in 72 of 253 (28%) patients at generator replacement. During median (quartiles) follow-up of 3.3 (1.8–5.3) years after generator replacement, 68 of 253 (27%) experienced appropriate ICD therapy. Patients with EF ≤35% were more likely to experience ICD therapy compared with those with EF >35% (12% versus 5% per year; hazard ratio, 3.57; P =0.001). On multivariable analysis, low EF predicted appropriate ICD therapy after generator replacement (hazard ratio, 1.96 [1.35–2.87] per 10% decrement; P =0.001). Death occurred in 25% of patients 5 years after generator replacement. Mortality was similar in patients with EF ≤35% and >35% (7% versus 5% per year; hazard ratio, 1.10; P =0.68). Atrial fibrillation (3.24 [1.63–6.43]; P <0.001) and higher blood urea nitrogen (1.28 [1.14–1.45] per increase of 10 mg/dL; P <0.001) were associated with mortality. Conclusions— Although approximately one fourth of patients with a primary prevention ICD and no previous therapy have EF >35% at the time of generator replacement, these patients continue to be at significant risk for appropriate ICD therapy (5% per year). These data may inform decisions on ICD replacement.