Catheter Ablation as First-Line Therapy in Persistent Atrial Fibrillation: Patient Characteristics and Clinical Outcomes.

BACKGROUND: In patients with persistent atrial fibrillation (PerAF), antiarrhythmic drugs (AADs) are considered a first-line rhythm-control strategy, whereas catheter ablation is a reasonable alternative. OBJECTIVES: This study sought to examine the prevalence, patient characteristics, and clinical outcomes of patients with PerAF who underwent catheter ablation as a first or second-line strategy. METHODS: This multicenter observational study included consecutive patients with PerAF who underwent first-time ablation between January 2020 and September 2021 in 9 medical centers in the United States. Patients were divided into those who underwent ablation as first-line therapy and those who had ablation as second-line therapy. Patient characteristics and clinical outcomes were compared between the groups. RESULTS: A total of 2,083 patients underwent first-time ablation for PerAF. Of these, 1,086 (52%) underwent ablation as a first-line rhythm-control treatment. Compared with patients treated with AADs as first-line therapy, these patients were predominantly male (72.6% vs 68.1%; P = 0.03), with a lower frequency of hypertension (64.0% vs 73.4%; P < 0.001) and heart failure (19.1% vs 30.5%; P < 0.001). During a mean follow-up of 325.9 ± 81.6 days, arrhythmia-free survival was similar between the groups (HR: 1.13; 95% CI: 0.92-1.41); however, patients in the second-line ablation strategy were more likely to continue receiving AAD therapy (41.5% vs 15.9%; P < 0.001). CONCLUSIONS: A first-line ablation strategy for PerAF is prevalent in the United States, particularly in men with fewer comorbidities. More data are needed to identify patients with PerAF who derive benefit from an early intervention strategy.

A novel automated peak frequency annotation algorithm for identifying deceleration zones and ventricular tachycardia ablation sites.

BACKGROUND: Current annotation of local fractionated signals during ventricular electroanatomic mapping (EAM) requires manual input subject to variability and error. OBJECTIVES: The purpose of this study was to evaluate a novel peak frequency (PF) annotation software for its ability to automatically detect late potentials (LPs) and local abnormal ventricular activity (LAVA), determine an optimal range for display, and assess its impact on isochronal late activation mapping (ILAM). METHODS: EAM data from 25 patients who underwent ventricular tachycardia (VT) ablation were retrospectively analyzed. Samplings of electrogram PFs from areas of normal bipolar voltage, areas of low voltage, and areas of low voltage with fractioned signals were performed. An optimal range of frequency display was identified from these patients and applied to a validation cohort of 10 prospective patients to assess high PF within scar as a predictor of VT ablation target sites, in particular deceleration zones (DZs) identified by ILAM, LP, and LAVA. RESULTS: Voltage and PF ranges of normal endocardial tissue varied widely. Using 220 Hz as a frequency cutoff value in areas of low bipolar voltage, areas of high fractionation were identified with sensitivity of 91% and specificity of 85% There was no significant reduction in targeted DZ surface areas, and colocalization with DZs was observed in all cases. Applied to the prospective cohort, PF predicted fractionated areas and DZ in 9 of 10 patients. CONCLUSION: A PF annotation algorithm with a cutoff of 220 Hz accurately identifies areas of fractioned signals and accurately predicts DZs during ILAM.

Utility of Very High-Output Pacing to Identify VT Circuits in Patients Manifesting Traditionally Inexcitable Scar.

BACKGROUND: Entrainment and pace mapping are used to identify critical components (CCs) of ventricular tachycardia (VT) circuits. In patients with dense myocardial scarring, VT circuits may elude capture at standard high pacing outputs (up to 10 mA at a 2-millisecond pulse width). OBJECTIVES: The purpose of this study was to assess the utility of very high-output pacing (V-HOP, 50 mA at 2 milliseconds) for identifying CCs of VT circuits after standard high pacing output failed to elicit capture in densely scarred myocardial tissue. METHODS: Our standard VT ablation approach included electroanatomic mapping for substrate characterization and entrainment and/or pace mapping to identify CCs of VT circuits. Patients that required V-HOP to capture sites of interest comprised the study cohort. Ablation endpoints were VT termination and noninducibility. RESULTS: Twenty-five patients (71 ± 10 years of age, all males) undergoing 26 VT ablations met the inclusion criteria. The mean left ventricular ejection fraction was 30% ± 14%, and 85% had ischemic cardiomyopathy. V-HOP was used to successfully entrain VT in 17 patients, yielding central isthmus sites in 10 and entrance/exit sites in 4. VT terminated with radiofrequency ablation at these sites in 15 patients. In 9 patients, V-HOP identified scar locations with a delayed exit. Acute procedural success was achieved in 24 patients without any adverse events. Over a follow-up period of 16 ± 21 months, 2 patients experienced VT recurrence requiring repeat ablation during which the same location was targeted successfully in 1 patient. CONCLUSIONS: In VT patients with a dense scar that is traditionally inexcitable, V-HOP can identify CCs of the re-entrant circuit and guide successful ablation.

Left Bundle Branch Area Pacing From a Femoral Approach in a Patient Without Superior Access.

Limited venous access and lateral left ventricular scar are impediments to traditional cardiac resynchronization therapy. We present a case where placement of an implantable cardioverter-defibrillator from a femoral approach while using left bundle branch area pacing led to clinical improvement. (Level of Difficulty: Intermediate.).

Loss of Right Atrial Pacing Lead Capture Due to Myocardial Infarction Obscuring Diagnosis on Electrocardiogram.

Right coronary artery occlusion can lead to failure to capture from the right atrial pacing lead. In this case, acute infarction resulted in failure of the right atrial lead to capture and thus increased right ventricular pacing. The new ventricular pacing masked the diagnosis of acute myocardial infarction. (Level of Difficulty: Intermediate.).

Utility of Prolonged Duration Endocardial Ablation for Ventricular Arrhythmias Originating From the Left Ventricular Summit.

OBJECTIVES: This study sought to explore whether prolonged duration (PD) radiofrequency ablation (RFA) from adjacent endocardial locations can improve catheter ablation (CA) outcomes of left ventricular summit (LVS) ventricular arrhythmias (Vas). BACKGROUND: CA of VAs originating from the LVS region can be challenging. METHODS: Patients undergoing CA of LVS VAs from January 1, 2015, to December 31, 2019, were included. Standard RFA approach involved incremental power titration (20-45 W) over 60-120 seconds with irrigated tip catheter to achieve 10%-12% impedance drop. Prolonged duration RFA involved similar power titration; however, lesion application was extended beyond 120 seconds (maximum 5 minutes). Lesions were confined to lowest aspect of aortic cusps and/or subvalvular LV outflow tract region (≤0.5 cm from the valve). Procedural success was defined as suppression of VA ≥30 minutes postablation and clinical success as no arrhythmia symptoms on follow-up and >80% reduction of VA burden on postprocedure monitor. RESULTS: This study included 102 patients (60±14 years old, 62% male): standard RFA in 80 and PD RFA in 38. Procedural success was achieved in 54 patients with standard and 32 patients with PD RFA (68% vs 84%; P = 0.05). Short-term clinical success was achieved in 48 patients (60%) with standard and 30 patients (79%) with PD RFA (P = 0.04). Two pericardial effusions occurred (1 in each group) and no steam pops were noted. Patients in whom standard RFA was successful were more likely to have R/S ratio >1 or absence of qS in lead I (odds ratio: 3.35; 95% CI: 1.20-9.35; P = 0.03). CONCLUSIONS: Prolonged duration RFA from adjacent endocardial locations is a safe and effective technique for successfully targeting challenging LVS VAs that fail standard RFA.

Bacterial etiology of sputum from tuberculosis suspected patients and antibiogram of the isolates.

OBJECTIVE: The current study aims to explore the bacteriology of sputum of tuberculosis (TB) suspected patients. A cross-sectional study was carried out in the sputum samples of 150 TB suspected patients visiting District Public Health Office, Bharatpur, Nepal. The samples were subjected to cultural, microscopic and biochemical analyses for the identification of the isolates. In addition, antibiotic susceptibility tests were carried out with a special focus on ESBL and MBL production following Clinical and Laboratory Standard Institute guidelines. RESULTS: Bacterial growth was recovered in 47% (71/150) of the TB suspected patients of which 12.66% (19/150) had pulmonary TB infection. Streptococcus spp. (9%) and Pseudomonas aeruginosa (9%) were the most frequently isolated bacteria. Enterobacteriaceae accounted for 35% of the total isolates. Occurrence of bacterial pathogens was more in males (69%) than in females (31%).The incidence of bacterial pathogen was seen associated with gender of the patients and with the TB infection (p < 0.05) but independent with age of the patients and HIV infection (p > 0.05). Tetracycline was effective against Streptococcus spp. whereas gentamicin was effective against Bacillus species. Imipenem and co-trimoxazole were effective drugs for Gram-negative isolates. Among 83 isolates, 35 were multi-drug resistant, 9 were ESBL producers and 4 were MBL producers.

Bioprosthetic aortic valve haemodynamic deterioration secondary to a thrombus.

A 77-year-old man with a history of coronary artery bypass grafting and surgical aortic valve replacement for severe aortic stenosis 2 years prior presented with exertional chest pain and shortness of breath. The patient underwent a thorough initial evaluation including a transthoracic echocardiogram and coronary angiogram without significant findings. One month later the patient presented with worsened symptoms and a repeat echocardiogram showed an increased mean aortic valve gradient of 87 mm Hg. The patient had to undergo reoperation for a surgical aortic valve replacement and was found to have an aortic bioprosthetic valve thrombus. This case suggests a mismatch between the aortic prosthesis and the patient's aortic root size.

SARS-CoV-2 Infection and Cardiovascular Disease: COVID-19 Heart.

Coronavirus disease (COVID-19) is a serious illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The symptoms of the disease range from asymptomatic to mild respiratory symptoms and even potentially life-threatening cardiovascular and pulmonary complications. Cardiac complications include acute myocardial injury, arrhythmias, cardiogenic shock and even sudden death. Furthermore, drug interactions with COVID-19 therapies may place the patient at risk for arrhythmias, cardiomyopathy and sudden death. In this review, we summarise the cardiac manifestations of COVID-19 infection and propose a simplified algorithm for patient management during the COVID-19 pandemic.

Relation of Pretransplant Peak Oxygen Consumption to Outcomes After Heart Transplantation.

Peak exercise oxygen consumption (pVO2) is an important predictor of prognosis in patients with heart failure (HF). The association between pretransplant pVO2 and post-transplantation outcomes in HF patients has not been previously studied. We identified adult OHT recipients with available pVO2 in the United Network for Organ Sharing registry (2000 to 2015). Patients were divided into 3 categories using Weber classification: class B (pVO2 16 to 20 ml/kg/min), class C (pVO2 10 to 16 ml/kg/min), and class D (pVO2 <10 ml/kg/min). Postoperative outcomes (mortality, renal failure, rejection) were compared between the groups. A total of 9,623 patients were included in this analysis; the mean age was 54 ± 11 years, 74% were male, 75% were white and 59% had nonischemic etiology of HF. The mean pVO2 was 11.7 ± 3.6 ml/kg/min: 1,202 (12.5%) in class B, 6,055 (62.9%) in class C, and 2,366 (24.6%) were in class D. At a median follow-up of 6.1 years, 2,730 (28.4%) died. Post-transplantation survival decreased with decreasing pVO2; 1 and 5-year survival: B (92%, 80%), C (90%, 79%), and D (87%, 75%), p <0.001 by log-rank. After multiple adjustments, patients in class D had significantly higher post-transplantation mortality compared with class C (Hazard Ratio (HR) 1.21 [1.03 to 1.43], p = 0.02). When analyzed as a continuous variable, each 1 ml/kg/min increase in pVO2 was associated with 2% decrease in mortality during follow-up (adjusted HR 0.98 [0.96 to 0.99], p <0.001). Patients in class D had significantly prolonged (>14 days) hospitalization (adjusted Odds Ratio (OR) 1.42 [1.20 to 1.68], p <0.001) and a trend toward increased need for dialysis (adjusted OR 1.36 [1.00 to 1.84], p = 0.05) compared with patients in class B. In this large cohort, lower pretransplant pVO2 was associated with greater mortality and morbidity after OHT. These results suggest that earlier transplantation might improve post-transplantation outcomes in advanced HF patients.

Arrhythmias in Relation to Mortality After Transcatheter Aortic Valve Replacement.

BACKGROUND: The purpose of this study was to identify predictors of mortality and potentially modifiable factors related to arrhythmias in patients that undergo transcatheter aortic valve replacement (TAVR). Patients that undergo TAVR are at risk for complete heart block requiring pacemaker implant. Additionally, other arrhythmias, specifically atrial fibrillation (AF), are common in this population. It is unclear how arrhythmias and their management contribute to mortality risk. METHODS: The study analyzed 176 patients who underwent TAVR at a single center. Factors associated with pacemaker implantation within 30 days were analyzed by logistic regression. Factors associated with mortality were analyzed by Kaplan-Meier and Cox regression analyses. RESULTS: Mean age was 80 ± 8.5 years. AF was present in 69 patients, and 39 received anticoagulation. Post-TAVR, a pacemaker was implanted in 25 patients within 30 days. Over a follow up of 566 ± 496 days, 49 patients died. In multivariable analysis, right bundle branch block remained significant (odds ratio 4.212, P = 0.012) for pacemaker implant within 30 days. The AF (hazard ratio [HR] 3.905, P = 0.001), albumin level (HR 0.316, P = 0.034), and diabetes (HR 2.323, P = 0.027) were predictors of death in a multivariate analysis, while pacemaker implant within 30 days was not. Patients with AF who were anticoagulated had improved survival in a stratified Kaplan-Meier analysis compared with those who were not anticoagulated (P = 0.0001). CONCLUSION: AF, diabetes, and low albumin levels are independently associated with mortality after TAVR. In particular, patients with AF who are not anticoagulated are at highest risk for death. Efforts to identify AF and consider anticoagulation should be emphasized.

Outcomes of Patients with Atrial Fibrillation Undergoing Percutaneous Coronary Intervention Analysis of National Inpatient Sample.

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia with a prevalence of 15% of patients over 80 years. Coronary artery disease co-exists in 20-30% of patients with atrial fibrillation. The need for triple anticoagulation therapy makes the management of these patients challenging following PCI. METHODS: Nationwide inpatient sample which is a set of longitudinal hospital inpatient databases was used to evaluate the outcome of patients with AF who underwent PCI. All patients undergoing PCI between 2002 and 2011 were included in the study. Specific ICD-9-CM codes were used to identify the study patients and their outcomes. RESULTS: There were 3,226,405 PCIs during the time period of the study of which 472,609 (14.6%) patients had AF. AF patients were older and predominantly male (60%). The number of PCIs had a declining trend from 2002 to 2011. Age adjusted inpatient mortality was significantly higher in PCI AF group compared to the PCI non-AF group (100.82 ±â€¯9.03 vs 54.07 ±â€¯8.96 per 100,000; P < 0.01). Post PCI predictors of mortality were AF (OR 1.56, CI 1.53-1.59), CKD (OR 1.41, CI 1.37-1.46), PAD (OR 1.20, CI 1.15-1.24), acute myocardial infarction (OR 2.42 CI 2.37-2.46 and cardiogenic shock (OR 13.92 CI 13.60-14.24) P < 0.001. CONCLUSION: AF is common in patients undergoing PCI and those AF patients have a higher age-adjusted all cause inpatient mortality. There is a decline in total number of PCIs over time in US. Atrial fibrillation, chronic kidney disease, peripheral artery disease, MI and cardiogenic shock were associated with increased mortality following PCI.

Prophylactic Left Ventricular Outflow Tract Septal Ablation Before Transcatheter Mitral Valve Replacement.

An 82-year-old woman with severe respiratory distress and limitations in functional status was found to have severe mitral valve stenosis with annular calcification and referred for transcatheter mitral valve replacement. Prophylactic alcohol septal ablation was used pre-procedurally to minimize mortality risk due to obstruction of the left ventricular outflow tract. (Level of Difficulty: Intermediate.).

Pulmonary Capillary Wedge Pressure Patterns During Exercise Predict Exercise Capacity and Incident Heart Failure.

BACKGROUND: Single measurements of left ventricular filling pressure at rest lack sensitivity for identifying heart failure with preserved ejection fraction (HFpEF) in patients with dyspnea on exertion. We hypothesized that exercise hemodynamic measurements (ie, changes in pulmonary capillary wedge pressure [PCWP] indexed to cardiac output [CO]) may more sensitively differentiate HFpEF and non-HFpEF disease states, reflect aerobic capacity, and forecast heart failure outcomes in individuals with normal PCWP at rest. METHODS AND RESULTS: We studied 175 patients referred for cardiopulmonary exercise testing with hemodynamic monitoring: controls (n=33), HFpEF with resting PCWP≥15 mm Hg (n=32), and patients with dyspnea on exertion with normal resting PCWP and left ventricular ejection fraction (DOE-nlrW; n=110). Across 1835 paired PCWP-CO measurements throughout exercise, we used regression techniques to define normative bounds of "PCWP/CO slope" in controls and tested the association of PCWP/CO slope with exercise capacity and composite cardiac outcomes (defined as cardiac death, incident resting PCWP elevation, or heart failure hospitalization) in the DOE-nlrW group. Relative to controls (PCWP/CO slope, 1.2±0.4 mm Hg/L/min), patients with HFpEF had a PCWP/CO slope of 3.4±1.9 mm Hg/L/min. We used a threshold (2 SD above the mean in controls) of 2 mm Hg/L/min to define abnormal. PCWP/CO slope >2 in DOE-nlrW patients was common (n=45/110) and was associated with reduced peak Vo2 (P<0.001) and adverse cardiac outcomes after adjustment for age, sex, and body mass index (hazard ratio, 3.47; P=0.03) at a median 5.3-year follow-up. CONCLUSIONS: Elevated PCWP/CO slope during exercise (>2 mm Hg/L/min) is common in DOE-nlrW and predicts exercise capacity and heart failure outcomes. These findings suggest that current definitions of HFpEF based on single measures during rest are insufficient and that assessment of exercise PCWP/CO slope may refine early HFpEF diagnosis.

Heart failure in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disorder characterized by a constellation of cardiovascular (CV) and non-CV manifestations. Even though CV complications such as accelerated atherosclerosis and elevated risk of myocardial infarction (MI) have been recognized for many years, there is limited evidence regarding SLE and its association with heart failure (HF). Traditional risk factors of atherosclerotic CV disease, as well as various SLE manifestations and therapies, independently or together, increase the risk of HF in this population. There is a need for sufficiently powered intervention studies focusing on specific risk factors to improve CV outcomes in SLE patients.

Synthesis of highly substituted benzene ring systems through three-component coupling of enyne imines, Fischer carbene complexes, and electron-deficient alkynes.

Three-component coupling of Fischer carbene complexes, enyne aldehyde hydrazones, and electron-deficient alkynes leads to simple benzoate derivatives in a process involving the formation of an N-aminopyrrole derivative, Diels-Alder reaction, and nitrene extrusion. The products are readily converted into isoquinolones through reaction with primary amines. The reaction proceeds best with highly substituted and electron-rich pyrroles even though these are the sterically least favorable substrates, and this reactivity trend is supported by a computational study.