Comparative Effectiveness of Aspirin Dosing in Cardiovascular Disease.

BACKGROUND: The appropriate dose of aspirin to lower the risk of death, myocardial infarction, and stroke and to minimize major bleeding in patients with established atherosclerotic cardiovascular disease is a subject of controversy. METHODS: Using an open-label, pragmatic design, we randomly assigned patients with established atherosclerotic cardiovascular disease to a strategy of 81 mg or 325 mg of aspirin per day. The primary effectiveness outcome was a composite of death from any cause, hospitalization for myocardial infarction, or hospitalization for stroke, assessed in a time-to-event analysis. The primary safety outcome was hospitalization for major bleeding, also assessed in a time-to-event analysis. RESULTS: A total of 15,076 patients were followed for a median of 26.2 months (interquartile range [IQR], 19.0 to 34.9). Before randomization, 13,537 (96.0% of those with available information on previous aspirin use) were already taking aspirin, and 85.3% of these patients were previously taking 81 mg of daily aspirin. Death, hospitalization for myocardial infarction, or hospitalization for stroke occurred in 590 patients (estimated percentage, 7.28%) in the 81-mg group and 569 patients (estimated percentage, 7.51%) in the 325-mg group (hazard ratio, 1.02; 95% confidence interval [CI], 0.91 to 1.14). Hospitalization for major bleeding occurred in 53 patients (estimated percentage, 0.63%) in the 81-mg group and 44 patients (estimated percentage, 0.60%) in the 325-mg group (hazard ratio, 1.18; 95% CI, 0.79 to 1.77). Patients assigned to 325 mg had a higher incidence of dose switching than those assigned to 81 mg (41.6% vs. 7.1%) and fewer median days of exposure to the assigned dose (434 days [IQR, 139 to 737] vs. 650 days [IQR, 415 to 922]). CONCLUSIONS: In this pragmatic trial involving patients with established cardiovascular disease, there was substantial dose switching to 81 mg of daily aspirin and no significant differences in cardiovascular events or major bleeding between patients assigned to 81 mg and those assigned to 325 mg of aspirin daily. (Funded by the Patient-Centered Outcomes Research Institute; ADAPTABLE ClinicalTrials.gov number, NCT02697916.).

Combined left atrial appendage occlusion and catheter ablation procedure for left atrial arrhythmias: A real-world, propensity-matched analysis.

INTRODUCTION: Real-world studies comparing safety and efficacy of combined percutaneous left atrial appendage occlusion (LAAO) and catheter ablation (CA) to LAAO alone are limited. METHODS: Patients from a large US hospital system undergoing combined LAAO and left-atrial CA from 8/2020 to 2/2024 were retrospectively analyzed and compared to a control group undergoing LAAO alone. Controls were identified using a 1:2 propensity score match based on LAAO device type (Watchman FLX vs. Amulet), CHA2D2-VASc and Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio [INR], Elderly, Drugs/alcohol (HAS-BLED) scores and compared for safety, sealing performance and clinical outcomes at 6 months. RESULTS: Patients were younger in the combined (n = 72) than in the control group (n = 144, 70.2 ± 7.3 vs. 76.7 ± 6.9 years, p < 0.001) but otherwise comparable with a mean CHA2D2-VASc score of 4.2 ± 1.1 and 4.4 ± 1.2 (p = 0.26) and HAS-BLED score of 2.2 ± 0.8 and 2.3 ± 0.7 (p = 0.34). Successful LAAO implantation rates were the same (95.8% vs. 95.8%, p = 0.99) with longer procedure times seen in the combined group (156.5 ± 53 vs. 56 ± 26 min, p < 0.001). Both major (1.4% vs. 2.1%, p = 0.72) and minor (27.8% vs. 19.4%, p = 0.17) in-hospital complications were similar between the combined and control group, respectively. At 45 days, presence of peri-device leak (18.3% vs. 30.4%, p = 0.07) and device related thrombosis (4.5% vs. 4.5%, p = 0.96) on transesophageal echocardiogram did not differ. Finally, all-cause mortality (0% vs. 1.4%, p = 0.99), thromboembolic (0% vs. 0%, p = 0.99) and bleeding (6.1% vs. 4.4%, p = 0.73) events during follow-up were comparable. CONCLUSION: This large, real-world analysis indicates comparable safety and efficiency of combined LAAO and CA when compared with LAAO alone.

Comparison of the effectiveness and safety of 2 aspirin doses in secondary prevention of cardiovascular outcomes in patients with chronic kidney disease: A subgroup analysis of ADAPTABLE.

BACKGROUND: Among patients with established cardiovascular disease, the ADAPTABLE trial found no significant differences in cardiovascular events and bleeding rates between 81 mg and 325 mg of aspirin (ASA) daily. In this secondary analysis from the ADAPTABLE trial, we studied the effectiveness and safety of ASA dosing in patients with a history of chronic kidney disease (CKD). METHODS: ADAPTABLE participants were stratified based on the presence or absence of CKD, defined using ICD-9/10-CM codes. Within the CKD group, we compared outcomes between patients taking ASA 81 mg and 325 mg. The primary effectiveness outcome was defined as a composite of all cause death, myocardial infarction, or stroke and the primary safety outcome was hospitalization for major bleeding. Adjusted Cox proportional hazard models were utilized to report differences between the groups. RESULTS: After excluding 414 (2.7%) patients due to missing medical history, a total of 14,662 patients were included from the ADAPTABLE cohort, of whom 2,648 (18%) patients had CKD. Patients with CKD were older (median age 69.4 vs 67.1 years; P < .0001) and less likely to be white (71.5% vs 81.7%; P < .0001) when compared to those without CKD. At a median follow-up of 26.2 months, CKD was associated with an increased risk of both the primary effectiveness outcome (adjusted HR 1.79 [1.57, 2.05] P < .001 and the primary safety outcome (adjusted HR 4.64 (2.98, 7.21), P < .001 and P < .05, respectively) regardless of ASA dose. There was no significant difference in effectiveness (adjusted HR 1.01 95% CI 0.82, 1.23; P = .95) or safety (adjusted HR 0.93; 95% CI 0.52, 1.64; P = .79) between ASA groups. CONCLUSIONS: Patients with CKD were more likely than those without CKD to have adverse cardiovascular events or death and were also more likely to have major bleeding requiring hospitalization. However, there was no association between ASA dose and study outcomes among these patients with CKD.

Dofetilide use is not associated with increased mortality in patients with left ventricular hypertrophy and atrial fibrillation.

BACKGROUND: Left ventricular hypertrophy (LVH) is common in patients with atrial fibrillation (AF), however, many antiarrhythmic drugs (AADs) are contraindicated. US guidelines recommend avoiding pure class III antiarrhythmics such as dofetilide in patients with significant LVH due to concern for an increased risk of death, however, clinical data is lacking. We sought to determine if dofetilide use was associated with increased mortality in patients with LVH. METHODS: Patients ≥18 years of age with AF and LVH ≥ 1.4 cm were included. A group of patients treated with dofetilide and a control group of patients without a history of AAD use were propensity matched. The primary outcome was all-cause mortality at 3 years and secondary outcomes were total number of all-cause hospitalizations and hospitalizations related to AF. RESULTS: There were 359 patients in each of the groups. Baseline variables were well-matched. The primary outcome of all-cause mortality occurred in 7% of patients in the dofetilide group and 12% of patients in the control group (hazard ratio: 0.90, 95% confidence interval: 0.53-1.53). Total all-cause hospitalizations were higher in the control group but hospitalizations for AF were no different. CONCLUSIONS: In a propensity-matched cohort of 718 patients with AF and LVH, dofetilide was not associated with increased mortality at 3 years. Our study adds to prior data demonstrating the safety of dofetilide in this population despite guideline recommendations against its use. Given the limited options for AF management in LVH patients, dofetilide may be reasonable for symptomatic AF management.

Ventricular pacing and myocardial function in patient with congenital heart block.

INTRODUCTION: Pacing-induced cardiomyopathy (PICM) is a potential complication of chronic right ventricular (RV) pacing, but its characterization in adult patients is often complicated by pre-existing cardiomyopathy. This study investigated the incidence of PICM in patients with congenital heart block (cHB) who have conduction disease from birth without confounding pre-existing cardiac conditions. METHODS AND RESULTS: This retrospective cohort analysis included 42 patients with cHB and baseline left ventricular ejection fraction (LVEF) ≥50%. Kaplan-Meier analysis was used to assess freedom from cardiomyopathy (defined as LVEF <50%) between paced and nonpaced patients. Patients were 26 ± 3 years old at first presentation, 64% were women and baseline LVEF was 60.0 ± 0.2%. Median follow-up from birth was 35 (interquartile range [IQR]: 20-42) years with a median of 6.7 years (IQR: 3.6-9.2) at our institution. Thirty-two patients received pacing at mean age 21 ± 3 years. Patients receiving a pacemaker (PM) were significantly more likely to develop a cardiomyopathy (p = .021) and no patient developed a cardiomyopathy in the absence of a PM. Four patients who developed a new cardiomyopathy were upgraded to biventricular pacing, leading to stabilization or improvement of LVEF. CONCLUSION: In a relatively young and healthy cHB cohort, RV pacing is associated with a higher risk of developing a cardiomyopathy. These data confirm the deleterious effects of RV pacing on myocardial function in patients without pre-existing structural cardiac disease and has clinical implications to the management of patients with cHB.

Management of systemic fungal infections in the presence of a cardiac implantable electronic device: A systematic review.

Evidence to inform the management of systemic fungal infections in the setting of a cardiac implantable electronic devices (CIED), such as a permanent pacemaker or implantable cardioverter-defibrillator, is scant and limited to case reports and series. The available literature suggests high morbidity and mortality. To better characterize the shared experience of these cases and their outcomes, we performed a systematic review. We investigated all published reports of systemic fungal infections-fungemia and fungal vegetative disease-in the context of CIED, drawing from PubMed, EMBASE, and the Cochrane database of systematic reviews, inclusive of patients who received treatment between January 2000 and May 2020. Exclusion criteria included presence of ventricular assist device and concurrent bacteremia, bacterial endocarditis, bacterial vegetative infection, or viremia. Among 6261 screened articles, 48 cases from 41 individual studies were identified. Candida and Aspergillus species were the most commonly isolated fungi. There was significant heterogeneity in antifungal medication selection and duration. CIED extraction-either transvenous or surgical-was associated with increased survival to hospital discharge (92%) and clinical recovery at latest follow-up (81%), compared to cases where CIED extraction was deferred (56% and 40%, respectively). Importantly, there were no prospective data, and the data were limited to individual case reports and one small case series. In summary, CIED extraction is associated with improved fungal clearance and patient survival. Reported antifungal regimens are heterogeneous and nonuniform. Prospective studies are needed to verify these results and define optimal antifungal regimens.

Maternal focal atrial tachycardia during pregnancy: A systematic review.

INTRODUCTION: The presentation and optimal management of maternal focal atrial tachycardia (AT) during pregnancy are unknown. The objective of this study is to conduct a comprehensive summary of the existing evidence. METHODS AND RESULTS: A systematic review of all reported cases of maternal focal AT during pregnancy was performed. The primary search queried PubMed using the MeSH terms "supraventricular tachycardia" and "pregnancy." A stepwise ancillary search included article bibliographies, citations listed by the Google internet search engine, and PubMed using the MeSH terms "atrial tachycardia" and "pregnancy." In total, 28 citations that described 32 patients were retrieved. A case from our institution was added. Detailed information was available for 30 patients. Clinical characteristics at presentation included a mean ± standard deviation of 28.3 ± 5.7 years for maternal age and 24.6 ± 7.7 weeks for gestation age. Suspected tachycardia-induced cardiomyopathy was present in 20 of 30 (67%) patients and left ventricular ejection fraction improved in 15 of 15 (100%) patients with follow-up measurements. Medication failure was common. Focal AT resolved spontaneously after delivery in eight of nine (89%) patients treated with only medications. Automaticity was suggested by discrete electrograms at sites of origin and lack of reported inducibility and termination with programmed stimulation in all patients who underwent electrophysiology studies. There were nine cases of successful catheter ablation with zero fluoroscopy since 2010. CONCLUSIONS: Automaticity is the dominant mechanism for patients with maternal focal AT during pregnancy. Catheter ablation with zero fluoroscopy is an emerging therapy for medically refractory cases.

Association of sex, age and education level with patient reported outcomes in atrial fibrillation.

BACKGROUND: In atrial fibrillation (AF), there are known sex and sociodemographic disparities in clinical outcomes such as stroke. We investigate whether disparities also exist with respect to patient-reported outcomes. We explored the association of sex, age, and education level with patient-reported outcomes (AF-related quality of life, symptom severity, and emotional and functional status). METHODS: The PaTH AF cohort study recruited participants (N = 953) with an AF diagnosis and age ≥ 18 years across 4 academic medical centers. We performed longitudinal multiple regression with random effects to determine if individual characteristics were associated with patient-reported outcomes. RESULTS: Women reported poorer functional status (ß - 2.23, 95% CI: -3.52, - 0.94) and AF-related quality of life (ß - 4.12, 95% CI: -8.10, - 0.14), and higher symptoms of anxiety (ß 2.08, 95% CI: 0.76, 3.40), depression (ß 1.44, 95% CI: 0.25, 2.63), and AF (ß 0.29, 95% CI: 0.08, 0.50). Individuals < 60 years were significantly (p < 0.05) more likely to report higher symptoms of depression, anxiety, and AF, and poorer AF-related quality of life. Lack of college education was associated with reporting higher symptoms of AF (ß 0.42, 95% CI: 0.17, 0.68), anxiety (ß 1.86, 95% CI: 0.26, 3.45), and depression (ß 1.11, 95% CI: 0.15, 2.38), and lower AF-related quality of life (ß - 4.41, 95% CI: -8.25, - 0.57) and functional status. CONCLUSION: Women, younger adults, and individuals with lower levels of education reported comparatively poor patient-reported outcomes. These findings highlight the importance of understanding why individuals experience AF differently based on certain characteristics.

Non-vitamin K oral anticoagulants versus warfarin for left atrial appendage thrombus resolution in nonvalvular atrial fibrillation or flutter.

BACKGROUND: Non-vitamin K oral anticoagulants (NOACs) have emerged as alternatives to vitamin K antagonists in select situations. For left atrial (LA) appendage thrombus in nonvalvular atrial fibrillation (AF) or flutter, guidelines recommend oral anticoagulation (OAC) for at least 3 weeks prior to reassessment. Data comparing NOACs to warfarin in this scenario are scarce. METHODS: A retrospective study identified subjects with nonvalvular AF or flutter who were: a) noted to have LA thrombus detected on transesophageal echocardiography (TEE), b) previously not receiving long-term OAC; and c) evaluated for resolution of LA thrombus by follow-up TEE between 3 weeks to less than 1 year of the initial TEE. RESULTS: The study included 45 subjects with mean age 63.2 years, 69% male, 78% white race/ethnicity, 42% paroxysmal, and mean CHA2 DS2 -VASc score 3.4 ± 1.7. All LA thrombi were confined to the appendage. OAC received included apixaban (3), dabigatran (13), rivaroxaban (6), and warfarin (23), The median follow-up time to repeat TEE was 67 (interquartile range, 49-96) days. LA appendage thrombus resolution rates were 76% for the entire cohort, 77% for NOACs, and 74% for warfarin. In univariable logistic regression analysis, LA appendage thrombus resolution was similar for NOACs when compared to warfarin (odds ratio, 1.20; 95% confidence interval, 0.31-4.69; P = .79). CONCLUSIONS: In patients nonvalvular AF or flutter who were OAC naïve at the time of diagnosis with LA appendage thrombus, complete resolution was similar between NOACs and warfarin.

Myocardial recovery after cardiac resynchronization therapy in left bundle branch block-associated idiopathic nonischemic cardiomyopathy: A NEOLITH II substudy.

BACKGROUND: Baseline predictors of myocardial recovery after cardiac resynchronization therapy (CRT) in left bundle branch block (LBBB)-associated idiopathic nonischemic cardiomyopathy (NICM) are unknown. METHODS: A retrospective study included subjects with idiopathic NICM, left ventricular ejection fraction (LVEF) ≤35%, and LBBB. Myocardial recovery was defined as post-CRT LVEF ≥50%. Logistic regression analyses described associations between baseline characteristics and myocardial recovery. Cox regression analyses estimated the hazard ratio (HR) between myocardial recovery status and adverse clinical events. RESULTS: In 105 subjects (mean age 61 years, 44% male, mean initial LVEF 22.6% ± 6.6%, 81% New York Heart Association class III, and 98% CRT-defibrillators), myocardial recovery after CRT was observed in 56 (54%) subjects. Hypertension, heart rate, and serum blood urea nitrogen (BUN) had negative associations with myocardial recovery in univariable analyses. These associations persisted in multivariable analysis: hypertension (odds ratio (OR), 0.40; 95% confidence interval (CI), 0.17-0.95; p = 0.04), heart rate (OR per 10 bpm, 0.69; 95% CI, 0.48-0.997; p = 0.048), and serum BUN (OR per 1 mg/dl, 0.94; 95% CI, 0.88-0.99; p = 0.04). Subjects with post-CRT LVEF ≥50%, when compared to <50%, had lower risk for adverse clinical events (heart failure hospitalization, appropriate implantable cardioverter-defibrillator shock, appropriate anti-tachycardia pacing therapy, ventricular assist device implantation, heart transplantation, and death) over a median follow-up of 75.9 months (HR, 0.38; 95% CI, 0.16-0.88; p = 0.02). CONCLUSION: In LBBB-associated idiopathic NICM, myocardial recovery after CRT was associated with absence of hypertension, lower heart rate, and lower serum BUN. Those with myocardial recovery had fewer adverse clinical events.

Sex-specific clinical outcomes after cardiac resynchronization therapy in left bundle branch block-associated idiopathic nonischemic cardiomyopathy: A NEOLITH II substudy.

BACKGROUND: Sex differences in clinical outcomes for left bundle branch block (LBBB)-associated idiopathic nonischemic cardiomyopathy (NICM) after cardiac resynchronization therapy (CRT) are not well described. METHODS: A retrospective cohort study at an academic medical center included subjects with LBBB-associated idiopathic NICM who received CRT. Cox regression analyses estimated the hazard ratios (HRs) between sex and clinical outcomes. RESULTS: In 123 total subjects (mean age 62 years, mean initial left ventricular ejection fraction 22.8%, 76% New York Heart Association class III, and 98% CRT-defibrillators), 55 (45%) were men and 68 (55%) were women. The median follow-up time after CRT was 72.4 months. Similar risk for adverse clinical events (heart failure hospitalization, appropriate implantable cardioverter-defibrillator shock, appropriate antitachycardia pacing therapy, ventricular assist device implantation, heart transplantation, and death) was observed between men and women (HR, 1.20; 95% confidence interval [CI] 0.57-2.51; p = 0.63). This persisted in multivariable analyses. Men and women had similar risk for all-cause mortality in univariable analysis, but men had higher risk in the final multivariable model that adjusted for age at diagnosis, QRS duration, and left ventricular end-diastolic dimension index (HR, 4.55; 95% CI, 1.26-16.39; p = 0.02). The estimated 5-year mortality was 9.5% for men and 6.9% for women. CONCLUSIONS: In LBBB-associated idiopathic NICM, men have higher risk for all-cause mortality after CRT when compared to women.

Rupture of amorphous graphene via void formation.

Apart from its unique and exciting electronic properties, many sensor based applications of graphene are purely based on its mechanical and structural properties. Here, we report a numerical and analytical study of a void in amorphous (small domain polycrystalline) graphene, and we show that the energetics of the void is a balance between the line tension cost versus the increased area gain. Using the concepts of classical nucleation theory, we show that the critical radius of a void formed in amorphous graphene at constant pressure is simply the ratio of the line tension at the void and the applied pressure. The values of the critical radius of the void for flat and buckled graphene are 3.48 Å and 3.31 Å, respectively, at 2 eV Å-2 pressure. We also show that the dominant finite size correction to the line tension is inversely proportional to the radius of the void in both flat and buckled cases. In contrast to conventional wisdom, with the help of a simple analytical model, we find that the shear modulus sets the lower limit of the line tension in the samples. This makes our study relevant for other two-dimensional amorphous materials such as h-BN, phosphorene, borophene, and transition metal dichalcogenides. Our results are useful for the better understanding of polycrystalline graphene under tension and therefore they have direct implications in the very fascinating field of strain engineering known as "straintronics" to manipulate or improve the properties of graphene.

Oral anticoagulation and left atrial thrombi resolution in nonrheumatic atrial fibrillation or flutter: A systematic review and meta-analysis.

BACKGROUND: Oral anticoagulation (OAC) is prescribed for left atrial thrombi (LAT) in nonrheumatic atrial fibrillation (AF) and/or atrial flutter (AFL). The study objective was to review the existing evidence regarding LAT resolution in nonrheumatic AF and/or AFL with OAC agents. METHODS: Data sources included PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) between January 1, 1991 and February 10, 2017. English-language studies that assessed LAT resolution with OAC agents in subjects with nonrheumatic AF and/or AFL, by serial transesophageal echocardiography, and with follow-up times ≥ 3 weeks and < 1 year, were selected. Study quality was assessed using recommendations adapted from the Agency for Healthcare Research and Quality. Pooled LAT resolution rates were evaluated for vitamin K antagonist (VKA) studies and low risk of bias warfarin studies. RESULTS: The pooled LAT resolution rate of 619 subjects from 16 VKA studies was 63.7% (95% confidence interval [CI], 53.3%-72.9%). The pooled LAT resolution rate of 94 subjects from four studies that specified warfarin use, exclusion of prior long-term therapeutic OAC, and target international normalized ratio (INR) ≥ 2.0 and/or average achieved INR ≥ 2.0 was 79.3% (95% CI, 69.8%-86.4%). Two studies in direct-acting oral anticoagulants (DOACs) reported LAT resolution rates of 89.5% (17 of 19) for dabigatran and 41.5% (22 of 53) for rivaroxaban. CONCLUSIONS: Warfarin is the most studied initial OAC agent for treating LAT in nonrheumatic AF and/or AFL with a resolution rate of nearly 80%. Further studies in DOACs are warranted.

New-onset left bundle branch block-associated idiopathic nonischemic cardiomyopathy and time from diagnosis to cardiac resynchronization therapy: The NEOLITH II study.

BACKGROUND: The optimal timing for cardiac resynchronization therapy (CRT) after diagnosis of new-onset left bundle branch block (LBBB)-associated idiopathic nonischemic cardiomyopathy (NICM) and treatment with guideline-directed medical therapy (GDMT) is unknown. The purpose of this study was to describe relationships between time from diagnosis to CRT and outcomes in new-onset LBBB-associated idiopathic NICM with left ventricular ejection fraction (LVEF) ≤35%. METHODS: A retrospective cohort study examined associations between time from diagnosis to CRT (≤9 months vs >9 months) and clinical and echocardiographic outcomes. RESULTS: In 123 subjects with LBBB-associated idiopathic NICM, time from diagnosis to CRT was ≤9 months in 60 (49%) subjects and 9 months in 63 (51%) subjects. Clinical outcomes were similar for those implanted ≤9 months versus >9 months for adverse clinical events (hazard ratio [HR], 0.85; 95% confidence interval [CI], 0.41-1.78; P = 0.67) and all-cause mortality (HR, 0.57; 95% CI, 0.19-1.70; P = 0.31). Multivariable analyses demonstrated similar results. In 105 subjects with post-CRT echocardiograms, LVEF improvement to >35% was more likely in those implanted ≤9 months when compared to >9 months (odds ratio [OR], 3.53; 95% CI, 1.32-9.46; P = 0.01). This association persisted in the final multivariable model adjusted for age at diagnosis, sex, QRS duration, post-GDMT LVEF, and time from CRT to post-CRT echocardiogram (OR, 5.10; 95% CI, 1.71-15.22; P = 0.004). CONCLUSION: In LBBB-associated idiopathic NICM, earlier CRT implantation was associated with more favorable cardiac remodeling. Delaying CRT may miss a critical period to halt and reverse progressive myocardial damage.

Probing the shape of a graphene nanobubble.

Gas molecules trapped between graphene and various substrates in the form of bubbles are observed experimentally. The study of these bubbles is useful in determining the elastic and mechanical properties of graphene and adhesion energy between graphene and the substrate, and manipulating the electronic properties via strain engineering. In our numerical simulations, we use a simple description of the elastic potential and adhesion energy to show that for small gas bubbles (∼10 nm) the van der Waals pressure is in the order of 1 GPa. These bubbles show universal shape behavior irrespective of their size, as observed in recent experiments. With our results, the shape and volume of the trapped gas can be determined via the vibrational density of states (VDOS) using experimental techniques such as inelastic electron tunneling and inelastic neutron scattering. The elastic energy distribution in the graphene layer which traps the nanobubble is homogeneous apart from its edge, but the strain depends on the bubble size; thus variation in bubble size allows control of the electronic and optical properties.

Predictors and implications of early left ventricular ejection fraction improvement in new-onset idiopathic nonischemic cardiomyopathy with narrow QRS complex: A NEOLITH substudy.

BACKGROUND: Predictors and implications of early left ventricular ejection fraction (LVEF) improvement with guideline-directed medical therapy (GDMT) in new-onset idiopathic nonischemic cardiomyopathy (NICM) with narrow QRS complex are not well described. The objectives were to describe predictors of LVEF improvement after 3 months on GDMT and adverse cardiac events based on post-GDMT LVEF status (≤35% vs. >35%). METHODS: A retrospective cohort study was performed in subjects with new-onset NICM, LVEF ≤35%, and narrow QRS complex. Associations for baseline variables with post-GDMT LVEF improvement and absolute change in LVEF (∆LVEFGDMT ) were assessed. Cox proportional hazards models assessed associations for post-GDMT LVEF status with adverse cardiac events. RESULTS: In 70 subjects, 31 (44%) had post-GDMT LVEF ≤35% after a median follow-up time of 97.5 days (interquartile range, 84-121 days). In final multivariable models, severely dilated left ventricular end-diastolic diameter (LVEDD), compared with normal LVEDD, strongly predicted post-GDMT LVEF ≤35% (odds ratio, 7.77; 95% confidence interval [CI], 1.39-43.49; p = .02) and ∆LVEFGDMT (ß = -15.709; standard error = 4.622; p = .001). Subjects with post-GDMT LVEF ≤35% were more likely to have adverse cardiac events over a median follow-up time of 970.5 days (unadjusted hazard ratio, 2.15; 95% CI, 0.93-4.96; p = .07). In the post-GDMT LVEF ≤35% group, 9 of 26 subjects (35%) had long-term LVEF > 35%. CONCLUSION: In new-onset NICM with narrow QRS complex, nondilated LVEDD predicted early LVEF improvement. Those with post-GDMT LVEF ≤35% had higher risk of adverse cardiac events, but a substantial proportion demonstrated continued long-term LVEF improvement.

Efficacy of Cryoballoon Pulmonary Vein Isolation in Patients With Persistent Atrial Fibrillation.

INTRODUCTION: Cryoballoon PVI has emerged as an alternative to radiofrequency PVI for the treatment of paroxysmal AF. The optimal strategy for patients with persistent AF is unclear as data are limited. METHODS: We analyzed a prospective registry of consecutive patients with persistent AF who underwent Cryoballoon PVI at a single center between 2011 and 2014. Patients were assessed for atrial arrhythmia recurrence after a 3-month blanking period at 6 months, 1 year, and 2 years postprocedure. Recurrence was based on typical symptoms, ECG, or event monitor evidence of AF. Kaplan-Meier analysis was used to estimate arrhythmia-free survival. RESULTS: Final analysis included 69 patients who underwent Cryoballoon PVI with a mean age 59.4 ± 8.1 years, 85.5% male, 53.6% HTN patients, CHA2DS2-VASC score 1.6 ± 1.2, and LA size 4.5 ± 0.6 cm. The single procedure atrial arrhythmia recurrence-free rate at 1-year postprocedure after a 3-month blanking period was 59% and 50% at a mean follow-up of 607 days. Of the recurrence-free group, 17% were taking previously ineffective antiarrhythmic medications. In comparing patients with persistent AF duration <1 year versus >1 year, there was a trend toward greater AF recurrence-free rates in the <1 year group (66% vs. 55%, P = 0.09). CONCLUSION: Cryoballoon PVI appears to be an effective initial strategy in treating persistent AF, with an AF recurrence-free rate of 59% at 1 year.

Characteristics and Outcomes of Concurrently Diagnosed New Rapid Atrial Fibrillation or Flutter and New Reduced Ejection Fraction.

BACKGROUND: Characteristics and outcomes of concurrently diagnosed new rapid atrial fibrillation (AF) or atrial flutter (AFL) and new heart failure with reduced left ventricular ejection fraction (LVEF) are not well described. METHODS: A retrospective cohort study of subjects referred for expedited transesophageal echocardiography-guided rhythm-control strategies for concurrent new rapid AF/AFL and new LVEF ≤ 40% diagnosed during the same admission was analyzed. RESULTS: Twenty-five subjects (median age 57 years; 96% male; 96% Caucasian; median CHA2 DS2 -VASc = 2) presented with new AF (n = 18) or AFL (n = 7) with rapid ventricular rate (median 135 beats/min) and new reduced LVEF (median 27%; range, 10-37.5%). Seven (28%) subjects had left atrial appendage thrombi (LAAT) and five (20%) subjects had heavy or binge alcohol use. Baseline characteristics were similar between those with and without LAAT. Thirteen subjects with AF and without LAAT underwent direct-current cardioversion (DCCV) and 10 (77%) had AF recurrence within 90 days. Improvement of long-term LVEF to >40% was comparable for subjects with and without initial LAAT (83% vs 94%; P = 0.46). Three of four subjects who received primary prophylaxis implantable cardioverter-defibrillators improved their LVEF to >35% after sinus rhythm maintenance. The median long-term follow-up time was 3.0 years. CONCLUSIONS: Subjects with concurrently diagnosed new rapid AF/AFL and new reduced LVEF are characterized by a high prevalence of LAAT and significant alcohol use. AF subjects without initial LAAT who underwent DCCV had a high 90-day AF recurrence rate. The presence of LAAT did not have a prognosticative effect on eventual LVEF improvement, which was observed in almost all subjects.