Local impedance-guided radiofrequency ablation with standard and high power: Results of a preclinical investigation.

BACKGROUND: Local impedance (LI) drop measured with microfidelity electrodes embedded in the tip of an ablation catheter accurately reflects tissue heating during radiofrequency (RF) ablation. Previous studies found 15-30 Ω LI drops created successful lesions, while more than 40 Ω drops were associated with steam pops. The objective of this study was to evaluate the safety and efficacy of LI-guided ablation using standard (30 W) and high-power (50 W) in a preclinical model. METHODS: RF lesions were created in explanted swine hearts (n = 6) to assess the feasibility of LI-guided ablation by targeting 10, 20, or 30 Ω (n = 20/group) drops. Subsequently, LI-guided ablation was evaluated in a chronic animal model (n = 8 Canines, 25-29 kg, 30/50 W). During the index procedure point-by-point intercaval line ablation and left inferior pulmonary vein (PV) isolation were performed. RF duration was at the operators' discretion but discontinued early if a 15-30 Ω drop was achieved. Operators attempted to avoid LI drops of more than 40 Ω. At 1-month, durable conduction block was evaluated with electroanatomic mapping followed by necropsy and histopathology. RESULTS: In explanted tissue, terminating ablation at 10, 20, or 30 Ω LI drops created statistically larger lesions (p < .05; 1.8 [1.6-2.4] mm, 3.3 [3.0-3.7] mm; 4.9 [4.3-5.5] mm). LI-guided high-power ablation in vivo significantly reduced RF duration per application compared to standard-power (p < .05; intercaval: 8.9 ± 5.2 vs. 18.1 ± 11.0 s, PV: 9.6 ± 5.4 vs. 23.2 ± 10.3 s). LI drops of 15-40 Ω were more readily achievable for high-power (90.1%, 318/353) than standard-power (71.7%, 243/339). All intercaval lines and PV isolations were durable (16/16) at 1-month. Necropsy revealed no major collateral injury to the pericardium, phrenic nerve, esophagus, or lungs. There was no pericardial effusion, stroke, tamponade, or PV stenosis. Vagal nerve injury was found in two 30 W animals after using 19.7 ± 13.9 and 19.5 ± 11.8 s RF applications. CONCLUSION: LI-guided ablation was found to be safe and efficacious in a chronic animal model. High-power ablation more readily achieved more than 15 Ω drops, reduced RF duration compared with standard-power, and had no major RF collateral injury.

Coronary artery aneurysm presenting as acute coronary syndrome: two case reports and a review of the literature.

Coronary artery aneurysm (CAA) is an uncommon coronary disease, with a reported incidence in adults ranging from 0.33 to 4.9%.It is usually considered a variant of coronary artery disease (CAD). CAA is associated with thrombus formation due to abnormal laminar flow, as well as abnormal platelet and endothelial-derived pathophysiologic factors within the CAA. CAA identified in the context of acute coronary syndrome (ACS) poses several unique management challenges. Optimal antiplatelet and anticoagulant therapy is the mainstay of therapy. Percutaneous intervention for CAA is associated with complications including distal embolization of thrombus, no-reflow phenomenon, stent malposition, dissection, and rupture. There are currently no accepted guidelines to direct the management of CAA in patients presenting with ACS. Preference for conservative vs. surgical or catheter-based management is controversial. We review the literature and report different treatment strategies for two cases with both CAA and ACS.

High-risk catheter ablation of refractory atrial fibrillation using Impella CP in a patient with cardiogenic shock.

BACKGROUND: Impella CP support during Posterior Vein Isolation/Posterior Wall Isolation (PVI/PWI) in the setting of persistent cardiogenic shock from refractory atrial fibrillation with rapid ventricular response (AF/RVR), has not been reported in the literature to the best of our knowledge. CASE: A 61-year-old male truck driver was admitted with acute HFrEF with AF/RVR 130 - 150. His EF was 20% with global hypokinesis. He was diuresed and cardioverted to sinus rhythm and had QTc of 532. He reverted to AF/RVR in less than 24 hours, requiring amiodarone drip. Shortly, amiodarone was discontinued because of intense anorexia, nausea, and vomiting. Class III and Class 1c agents were contraindicated due to prolonged QTc and cardiomyopathy. He developed cardiogenic shock, worsening cardiorenal syndrome, and shock liver requiring continuous renal replacement therapy (CRRT). Inotropes and vasopressors were contraindicated. AVN ablation was refused because he wanted to return to truck driving. EF dropped to 10%, and moderate RV dysfunction ensued. Right heart catheterization showed PASP 53, PADP 38, and PCWP 37 with RAP 28mmHg. Coronary angiogram was normal. An Impella device was inserted, and support was set to P6 with 3.4 L/min cardiac output. PVI with cryoablation, PWI, and anterior mitral isthmus ablation was successful. The adequacy of isolation was verified by demonstrating a complete exit block 30 mins after ablation. Normal sinus rhythm was restored after cardioversion. Echo 48 hours later revealed improvement in EF from 10% to 40% in sinus rhythm. Impella and CRRT were weaned. He was discharged on GDMT. CONCLUSION: There are no recommendations regarding PVI for AF/RVR on mechanical circulatory support (MCS). MCS assisted PVI/PWI may be the only resort to restore hemodynamic stability in cases where a pacemaker is not desirable. PVI/PWI is a lengthy procedure; the use of the Impella support for PVI/PWI in cardiogenic shock allows adequate time for exit block testing and PWI. The operator can do thorough mapping and ablation, knowing that the patient is receiving adjustable support based on hemodynamic demands. We had a good outcome; nevertheless, the potential pitfalls are unknown.

Coronary artery fistulae.

Coronary artery fistulae (CAF) are rare congenital or acquired in which a connection forms between one of the coronary arteries and a heart chamber or with other vessels. This paper describes three cases of CAF along with their initial presentation, imaging findings and management. The first case is a rare form of CAF in which the left circumflex coronary artery fistula empty into left ventricle. We discuss the different types of CAF along with their prevalence and the different imaging tools that could be utilized to identify CAF. There is no unifying consensus on treatment strategy for symptomatic fistulae and we proposed a management algorithm that could be used to make a decision for intervention versus observation. We discuss options for intervention- surgical, catheter-based and medical therapy.

Peptide Extract from Red Kidney Beans, Phaseolus vulgaris (Fabaceae), Shows Promising Antimicrobial, Antibiofilm, and Quorum Sensing Inhibitory Effects.

The rapid spread of multidrug-resistant bacteria has led to an increased risk of infectious diseases. Pseudomonas aeruginosa, in particular, poses a significant obstacle due to its propensity to rapidly acquire resistance to conventional antibiotics. This has resulted in an urgent need for the development of new classes of antibiotics that do not induce resistance. Antimicrobial peptides (AMPs) have been studied as potential small-molecule antibiotics due to their unique mode of action. In this study, peptides were extracted from the seeds of Phaseolus vulgaris (Fabaceae), and the antimicrobial activities of the extract were evaluated using microbroth dilution against five different microorganisms. The extract showed antimicrobial activity against all tested organisms with minimum inhibitory concentrations (MIC) of 2.5 mg/mL, except for Candida albicans and Pseudomonas aeruginosa, which had MICs of 1.25 mg/mL. The extract was also bacteriostatic for all tested organisms. The crude peptide extract from Phaseolus vulgaris was further studied for its antibiofilm activity against Pseudomonas aeruginosa, a common nosocomial pathogen associated with biofilm formation. The extract showed good antibiofilm activity at 1/2 MIC. The extract also inhibited the expression of pyocyanin and pyoverdine (virulence factors of P. aeruginosa whose expression is mediated by quorum sensing) by 82% and 66%, respectively. These results suggest that the peptide mix from Phaseolus vulgaris may inhibit biofilm formation and virulence factor expression by interfering with cell-to-cell communication in Pseudomonas aeruginosa. The ability of the extract to inhibit the growth and biofilm formation of all tested organisms indicates its potential as an antimicrobial agent that could be further studied for drug discovery.

Enhanced network load balancing technique for efficient performance in software defined network.

Hash collisions and redirection of loads are major limitations for recent Hash IP algorithms. To overcome this, we propose a new Hash IP algorithm dubbed HDW in network load balancing (NLB) to increase network's efficiency, availability and scalability. We achieve the new Hash IP load balancing algorithm via a constructive merger with weighted scheduler (WS) technique and dynamic switching of routing path (DSP). This helps to reduce delays, jitters and additionally assures some level of security owing to the hashing process. Our findings after comprehensive simulations and performance evaluation depicts that our proposed HDW algorithm is relatively efficient as against other related load balancing algorithms for software defined network.

Comparative Outcomes of TAVR in Mixed Aortic Valve Disease and Aortic Stenosis: A Meta-analysis.

INTRODUCTION: Transcatheter aortic valve replacement (TAVR) has become a suitable alternative to surgical aortic valve replacement (SAVR) for the treatment of symptomatic severe aortic stenosis (AS). A high proportion of patients with AS have mixed aortic valve disease (MAVD) with mild or more concurrent aortic regurgitation (AR). Differential outcomes of TAVR among patients with AS and MAVD have not been well characterized. We compared 1-year mortalities following TAVR among patients with MAVD and AS. METHODS: We conducted a meta-analysis of studies published in PubMed/Medline. The primary outcome was 1-year all-cause mortality following TAVR among patients with MAVD vs. AS. Secondary endpoints were: (1) incidence of AR within 30 days following TAVR (post TAVR AR); and (2) 1-year all-cause mortality within each group stratified according to severity of post TAVR AR. RESULTS: Nine studies involving 9505 participants were included in the analysis. At 1 year following TAVR, mortality was lower in MAVD than in AS; HR 0.89, 95% CI 0.81-0.98. The mortality advantage increased when pre-TAVR AR was moderate or more; HR 0.84, 95% CI 0.72-0.99. The mortality advantage was attenuated after correction for publication bias. There was a higher risk of post TAVR AR in the MAVD group; OR 1.51, 95% CI 1.20-1.90 but the impact on mortality of moderate vs. mild post TAVR AR was greater among patients with AS than in patients with MAVD HR 1.67 95% CI 0.89-3.14 vs. 0.93 95% CI 0.47-1.85. CONCLUSIONS: Patients with MAVD have similar or improved survival 1 year after TAVR compared to those with AS.

Reducing costs and improving care after hospitalization: Economic evaluation of a novel transitional care clinic.

Transitional care management (TCM) is a novel strategy for reducing costs and improving clinical outcomes after hospitalization but remains under-utilized. An economic analysis was performed on a hospital-based transition of care clinic (TCC) open to all patients regardless of payor status. TCC reduced re-hospitalization and emergency department (ED) utilization at six-month follow up. A cost-consequence analysis based on real world data found the TCC intervention to be cost effective relative to usual care. Hospital managers should consider adoption of TCC to improve patient care and reduce costs.

A rapidly enlarging giant pericardial cyst resected by video-assisted thoracoscopic surgery (VATS): A case report.

Pericardial cysts are rare mediastinal masses of congenital etiology. Giant pericardial cysts measuring greater than 10 cm are even rarer. In a small proportion of cases, the natural history of pericardial cyst is one of continuous slow growth. Symptomatic pericardial cysts can be treated initially with percutaneous aspiration. Very large or complicated cysts are preferentially treated by open surgical excision. We present a case of a rapidly growing giant pericardial cyst in a 36-year-old male. The cyst was an overlooked incidental finding on a computed tomography scan of the abdomen and pelvis obtained for unrelated reasons seven years prior. At that time, it measured 4 × 2 × 1 cm. No further evaluation was carried out until he became symptomatic, at which time the cyst had a more than 2-fold increase in maximum diameter to a size of 11 × 10 × 6 cm. This resulted in compression of adjacent cardiac structures without hemodynamic sequalae. The cyst was completely excised via video-assisted thoracoscopic surgery, facilitated by initial intra-operative needle aspiration to reduce the size for safe mobilization. .

Coronary Artery Fistulae in Adult: Two Decades of Experience in Clinical Presentation, Angiographic Feature, and Management.

Coronary artery fistula (CAF) in adults is a rare but significant coronary artery anomaly. Main data on that rare disease were mostly obtained from case reports and small studies. In presented study, we share our two-decade experience on the clinical and angiographic characteristics of CAF. The data were collected retrospectively by analyzing the angiographic data between January 1, 2000 and December 31, 2019. Demographic data, clinical data, laboratory, and cardiac catheterization reports were reviewed. CAFs were found in 40 patients (0.06%). There were 22 male (55%) patients. The mean age was 61.2 years. Twenty-nine patients (72.5%) had small, 4 patients (10%) had medium, and 7 patients (17.5%) had large CAFs. The majority of study population had solitary CAF ( n = 31, 77.5%). The pulmonary artery is the major side of fistula drainage ( n = 20, 50%). The study population was divided into two groups as follow: group 1-small CAFs 29 (72.5%), group 2-medium and large CAF (MLCAF) 11 (27.5%). Patients with MLCAFs had more atrial fibrillation, abnormal coronary morphology, and multiple fistulae. In patients with hemodynamically significant CAFs, 7 (17.5%) patients had surgical ligation and 3 (7.5%) patients had transcutaneous closure. Three patients died during mean follow-up period of 5 years. The incidence and the pattern of CAFs in our study were similar to previous studies. Clinical course of small fistulae was benign. Symptomatic MLCAFs need to be treated by transcatheter or surgical way and should be individualized per patient.

Eosinophilic Myocarditis: Is Endomyocardial Biopsy Essential for Diagnosis in the Era of Advanced Cardiac Imaging?

A 60-year-old female presented with dyspnea and chest pressure. Clinical presentation, laboratory data, echocardiography, and cardiac magnetic resonance (CMR) imaging findings confirmed diagnosis of eosinophilic myocarditis and obviated unnecessary invasive endomyocardial biopsy. She was treated with oral steroid and oral anticoagulation. Follow-up CMR imaging showed resolution of the left ventricle thrombus with improvement in endomyocardial inflammation.

A Case Report of Atezolizumab Induced Tumor Lysis Syndrome.

BACKGROUND Advanced urothelial carcinoma has been associated with poor prognosis due to high resistance to chemotherapy and radiation until immunotherapeutic agents, such as atezolizumab, emerged as an option and have shown improved survival. However, atezolizumab is associated with side effects, which were mainly autoimmune. In this case study, we report on a rare case of atezolizumab-induced tumor lysis syndrome. CASE REPORT A 67-year-old female with a primary diagnosis of metastatic urothelial carcinoma who presented to the emergency department with generalized weakness associated with nausea and vomiting 8 days after her first cycle of atezolizumab. Laboratory values showed hyperphosphatemia, hyperuricemia, hypocalcemia, and acute kidney injury consistent with tumor lysis syndrome. CONCLUSIONS In our report, we highlight tumor lysis syndrome as a potential reaction to atezolizumab; a condition that requires prophylaxis and close laboratory monitoring.

A Rare Case of Thyrotoxic Periodic Paralysis After Epidural Steroid Injection: A Case Report and Literature Review.

BACKGROUND Thyrotoxic periodic paralysis (TPP) is a rare cause of acute paralysis, which if not promptly recognized and treated, can lead to significant morbidity and mortality. TPP can be precipitated by several factors, including a high carbohydrate diet and exercise. This report is of a rare case of TPP after epidural steroid injection in a young man, with a review of the literature of previous cases. CASE REPORT A 36-year-old Asian man presented to the emergency department with sudden onset of paralysis of all his limbs following epidural steroid injection for traumatic low back pain. At presentation, he was found to have severe hypokalemia of 1.8 mEq/L. Further investigations led to the diagnosis of hyperthyroidism and Graves' disease. In the process of correcting his potassium, there was an unexpected rebound hyperkalemia that was successfully corrected. He had a rapid recovery and an early discharge from hospital. CONCLUSIONS Although several factors can lead to paralysis after an epidural steroid injection, TPP should be considered in the differential diagnosis, especially in individuals who have predisposing factors of ethnicity and gender. If patients have undiagnosed hyperthyroidism on presentation, the diagnosis of TPP can be delayed or missed. In the management of patients with TPP, care should be taken when correcting potassium levels.

Pathogens, prejudice, and politics: the role of the global health community in the European refugee crisis.

Involuntary migration is a crucially important global challenge from an economic, social, and public health perspective. The number of displaced people reached an unprecedented level in 2015, at a total of 60 million worldwide, with more than 1 million crossing into Europe in the past year alone. Migrants and refugees are often perceived to carry a higher load of infectious diseases, despite no systematic association. We propose three important contributions that the global health community can make to help address infectious disease risks and global health inequalities worldwide, with a particular focus on the refugee crisis in Europe. First, policy decisions should be based on a sound evidence base regarding health risks and burdens to health systems, rather than prejudice or unfounded fears. Second, for incoming refugees, we must focus on building inclusive, cost-effective health services to promote collective health security. Finally, alongside protracted conflicts, widening of health and socioeconomic inequalities between high-income and lower-income countries should be acknowledged as major drivers for the global refugee crisis, and fully considered in planning long-term solutions.