Implantable loop recorders in patients with Brugada syndrome: the BruLoop study.

BACKGROUND AND AIMS: Available data on continuous rhythm monitoring by implantable loop recorders (ILRs) in patients with Brugada syndrome (BrS) are scarce. The aim of this multi-centre study was to evaluate the diagnostic yield and clinical implication of a continuous rhythm monitoring strategy by ILRs in a large cohort of BrS patients and to assess the precise arrhythmic cause of syncopal episodes. METHODS: A total of 370 patients with BrS and ILRs (mean age 43.5 ± 15.9, 33.8% female, 74.1% symptomatic) from 18 international centers were included. Patients were followed with continuous rhythm monitoring for a median follow-up of 3 years. RESULTS: During follow-up, an arrhythmic event was recorded in 30.7% of symptomatic patients [18.6% atrial arrhythmias (AAs), 10.2% bradyarrhythmias (BAs), and 7.3% ventricular arrhythmias (VAs)]. In patients with recurrent syncope, the aetiology was arrhythmic in 22.4% (59.3% BAs, 25.0% VAs, and 15.6% AAs). The ILR led to drug therapy initiation in 11.4%, ablation procedure in 10.9%, implantation of a pacemaker in 2.5%, and a cardioverter-defibrillator in 8%. At multivariate analysis, the presence of symptoms [hazard ratio (HR) 2.5, P = .001] and age >50 years (HR 1.7, P = .016) were independent predictors of arrhythmic events, while inducibility of ventricular fibrillation at the electrophysiological study (HR 9.0, P < .001) was a predictor of VAs. CONCLUSIONS: ILR detects arrhythmic events in nearly 30% of symptomatic BrS patients, leading to appropriate therapy in 70% of them. The most commonly detected arrhythmias are AAs and BAs, while VAs are detected only in 7% of cases. Symptom status can be used to guide ILR implantation.

Utilizing Human-Induced Pluripotent Stem Cells to Study Cardiac Electroporation Pulsed-Field Ablation.

BACKGROUND: Electroporation is a promising nonthermal ablation method for cardiac arrhythmia treatment. Although initial clinical studies found electroporation pulsed-field ablation (PFA) both safe and efficacious, there are significant knowledge gaps concerning the mechanistic nature and electrophysiological consequences of cardiomyocyte electroporation, contributed by the paucity of suitable human in vitro models. Here, we aimed to establish and characterize a functional in vitro model based on human-induced pluripotent stem cells (hiPSCs)-derived cardiac tissue, and to study the fundamentals of cardiac PFA. METHODS: hiPSC-derived cardiomyocytes were seeded as circular cell sheets and subjected to different PFA protocols. Detailed optical mapping, cellular, and molecular characterizations were performed to study PFA mechanisms and electrophysiological outcomes. RESULTS: PFA generated electrically silenced lesions within the hiPSC-derived cardiac circular cell sheets, resulting in areas of conduction block. Both reversible and irreversible electroporation components were identified. Significant electroporation reversibility was documented within 5 to 15-minutes post-PFA. Irreversibly electroporated regions persisted at 24-hours post-PFA. Per single pulse, high-frequency PFA was less efficacious than standard (monophasic) PFA, whereas increasing pulse-number augmented lesion size and diminished reversible electroporation. PFA augmentation could also be achieved by increasing extracellular Ca2+ levels. Flow-cytometry experiments revealed that regulated cell death played an important role following PFA. Assessing for PFA antiarrhythmic properties, sustainable lines of conduction block could be generated using PFA, which could either terminate or isolate arrhythmic activity in the hiPSC-derived cardiac circular cell sheets. CONCLUSIONS: Cardiac electroporation may be studied using hiPSC-derived cardiac tissue, providing novel insights into PFA temporal and electrophysiological characteristics, facilitating electroporation protocol optimization, screening for potential PFA-sensitizers, and investigating the mechanistic nature of PFA antiarrhythmic properties.

Foot Surgery Using Resorbable Magnesium Screws.

The use of bioabsorbable magnesium (Mg) screws is new in foot surgery. Their relative merit over conventional titanium screws has not yet been proven. This prospective case series study was conducted to compare the clinical and radiological outcomes of bioabsorbable Mg screws and titanium screws. A consecutive series of patients (n = 60; 11 men and 49 women) underwent corrective hallux valgus surgery. The minimum follow-up period was 1 year. The assessment was based on a patient questionnaire, including the American Orthopedic Foot and Ankle Society (AOFAS) hallux valgus score, visual analog scale, patient's global impression of change (PGIC), and fifth metatarsus circumference (IF5C). The radiographic assessment included the intermetatarsal and hallux valgus angles, as well as time to osteotomy union and hardware failure. At 1 year, similar results were obtained radiographically. The healing of the osteotomies was significantly faster in the Mg group. Hardware failure was common in the Mg group (5/26) than in the TI group (0/34) but hardware removal was more common in the TI group (6/34) versus the MG group (0/26). IF5C increased by 8 ± 2 mm in the Mg group. The AOFAS and PGIC scores at 6 months were similar. Validated foot scores and radiographic analysis indicated that there was no detectable difference between the groups. The fast achievement of osteotomy union compensates for a high rate of hardware failure, resulting in patient satisfaction and avoiding reoperation for hardware removal.

Differential effect of high-frequency electroporation on myocardium vs. non-myocardial tissues.

AIMS: Pulsed-field ablation (PFA) is an emerging non-thermal ablation method based on the biophysical phenomenon of electroporation. Data on PFA cardiac selectivity nature and tissue-specific thresholds are lacking. We aim to compare the in vivo differential effect of high-frequency irreversible electroporation (HF-IRE) protocols on various tissues. METHODS AND RESULTS: Twenty-three Sprague-Dawle rodents were allocated into three different protocols of 300, 600, and 900 V, respectively, while delivering twenty 100 µs bursts of a 150 kHz biphasic square wave to five tissues; cardiac muscle, skeletal muscle, liver, carotid artery and sciatic nerve. Lesions were evaluated quantitatively by histologic analysis and by morphometric evaluation. There were eight, seven and eight animals in the 300, 600, and 900 V protocols, respectively. High-frequency electroporation protocols showed a graded effect on myocardial tissue with larger lesions in the 900 V protocol compared with the other two protocols as demonstrated by width (P = 0.02), length (P = 0.01) and fibrosis ratio (P = 0.001). This effect was not observed for other tissues with attenuated degree of damage. No damage to the carotid artery was observed in all protocols. Partial damage to the sciatic nerve was observed in only two samples (25%) in the 600 V group and in one sample (14.3%) in the 900 V group. CONCLUSION: Electroporation effect is tissue-specific such that myocardium is more prone to electroporation damage compared with neural and vascular tissues. Our results suggest no neural or vascular damage with using a low-amplitude HF-IRE protocol. Further investigation is warranted to better identify other tissue-specific thresholds.

Prevalence and clinical implication of thrombocytopenia and heparin-induced thrombocytopenia in patients who are critically ill with COVID-19.

As the COVID-19 pandemic continues to evolve, different clinical manifestations are better understood and studied. These include various haematologic disorders that have been shown to be associated with increased morbidity and mortality. We studied the prevalence of one unusual manifestation, heparin-induced thrombocytopenia (HIT) and its clinical implications in patients who are severely ill with COVID-19 in a single tertiary centre in Israel. The presence of thrombocytopenia, disseminated intravascular coagulation (DIC) and HIT, and their association with clinical course and outcomes were studied. One-hundred and seven patients with COVID-19 were included. Fifty-seven (53.2%) patients developed thrombocytopenia, which was associated with the worst outcomes (ventilation, DIC and increased mortality). Sixteen (28.0%) patients with thrombocytopenia were positive for HIT, all of which were supported by extracorporeal devices. HIT was independently associated with ventilation days, blood product transfusions, longer hospitalisation and mortality.Platelet abnormalities and HIT are common in patients who are critically ill with COVID-19 and are associated with the worst clinical outcomes. The mechanisms underlying HIT in COVID-19 are yet to be studied; HIT may contribute to the dysregulated immunologic response associated with COVID-19 critical illness and may play a significant part in the coagulopathy seen in these patients. As many patients with COVID-19 require aggressive thromboprophylaxis, further understanding of HIT and the implementation of appropriate protocols are important.

Automated processing of thermal imaging to detect COVID-19.

Rapid and sensitive screening tools for SARS-CoV-2 infection are essential to limit the spread of COVID-19 and to properly allocate national resources. Here, we developed a new point-of-care, non-contact thermal imaging tool to detect COVID-19, based on advanced image processing algorithms. We captured thermal images of the backs of individuals with and without COVID-19 using a portable thermal camera that connects directly to smartphones. Our novel image processing algorithms automatically extracted multiple texture and shape features of the thermal images and achieved an area under the curve (AUC) of 0.85 in COVID-19 detection with up to 92% sensitivity. Thermal imaging scores were inversely correlated with clinical variables associated with COVID-19 disease progression. In summary, we show, for the first time, that a hand-held thermal imaging device can be used to detect COVID-19. Non-invasive thermal imaging could be used to screen for COVID-19 in out-of-hospital settings, especially in low-income regions with limited imaging resources.

Comparing High-Frequency With Monophasic Electroporation Protocols in an In Vivo Beating Heart Model.

This study compared monophasic 100-µs pulses with high-frequency electroporation (HF-EP) bursts using an in vivo animal model. Myocardial damage was evaluated by histologic analysis. Compared with 10 monophasic pulses, 20 bursts of HF-EP at 100 and 150 kHz were associated with less damage. However, when the number of HF-EP bursts was increased to 60, myocardial damage was comparable to that of the monophasic group. HF-EP protocols were associated with attenuated collateral muscle contractions. This study shows that HF-EP is feasible and effective and that pulse frequency has a significant effect on extent of ablation.

Comparing the Temperature Effect of Dedicated Minimally Invasive Motor System to the Discontinuous Use of Rotatory Burrs in the Correction of Hallux Valgus.

The purpose of this study was to compare 2 motor systems for percutaneous osteotomy. The study consisted of 2 stages. In the first stage, bone temperatures during osteotomy using burrs or saw was measured using a thermal camera. In the second stage, the tissue and burr temperature elevation during surgery in 80 consecutive patients (96 feet) with hallux valgus undergoing distal first metatarsal and phalangeal osteotomies (hallux and in 61/96 feet lesser digits) were measured. The burr osteotomy procedure included the use of irrigated 2- or 4.1 mm rotary wedge burrs in discontinuous cutting bursts of less than 20 seconds. Tissue surface temperature was measured with a thermal camera. The temperature generated during the procedure was found to be significantly associated with the burr diameter used but was not affected by the type of motor. At the 6-week visit, thickness of the soft tissues over the first metatarsal head was similar in both groups. Temperature control using a noninvasive thermal camera is recommended to prevent tissue damage associated with heat generated during the use of rotary burrs. A dedicated low-speed high-torque system does not seem to be necessary and standard orthopaedic equipment can be used.Levels of Evidence: Level II: Comparative prospectively collected series.

[PERCUTANEOUS CORRECTION OF FOREFOOT DEFORMITIES IN DIABETIC PATIENTS IN ORDER TO PREVENT PRESSURE SORES - TECHNIQUE AND RESULTS IN 20 CONSECUTIVE PATIENTS].

INTRODUCTION: Diabetes mellitus is a 21st century pandemic. Due to life-span prolongation combined with the increased rate of diabetes, a growing population of patients is afflicted with neuropathic foot deformities. Traditional operative repair of these deformities is associated with a high complication rate and relatively common infection incidence. In recent years, in order to prevent these complications, percutaneous deformity correction methods were developed. OBJECTIVES: Description of experience accumulated in treating 20 consecutive patients with diabetic neuropathic foot deformities treated in a percutaneous fashion. METHODS: A consecutive series of patients treated at our institute for neuropathic foot deformity was assessed according to a standard protocol using the AOFAS forefoot score and the LUMT score performed at baseline as well as at 6 months and 12 months. Treatment related complications were monitored. RESULTS: All procedures were performed in an ambulatory setting using local anesthesia. A total of 12 patients had soft tissue corrections, and 8 had a combined soft tissue and bone correction. Baseline AOFAS score was 48±7 and improved to 73±9 at six months and 75±7 at one year. LUMT score in 11 patients with a chronic wound decreased from 22±4 to 2±1 at one year post-op. One patient required hospitalization due to post-op bleeding. CONCLUSIONS: Percutaneous techniques allow deformity correction of diabetic feet, including those with open wounds in an ambulatory setting with a low complication rate.

Non-Small-cell Lung Cancer Patients With Adenocarcinoma Morphology Have a Better Outcome Compared With Patients Diagnosed With Non-Small-cell Lung Cancer Favor Adenocarcinoma.

BACKGROUND: Non-small-cell lung cancer (NSCLC) includes 2 major histologic subtypes: squamous cell carcinoma and non-squamous carcinoma, mainly adenocarcinoma, a distinction that carries significant clinical and therapeutic implications. NSCLC is diagnosed as adenocarcinoma or as squamous cell carcinoma on the basis of histologic parameters. However, when morphology is inconclusive, tumors with immunohistochemistry (IHC) findings characteristic of adenocarcinoma are referred to as "NSCLC favor adenocarcinoma" (NFA). Our aim was to evaluate whether pulmonary adenocarcinoma diagnosis on the basis of morphology had a similar prognosis compared with NFA. PATIENTS AND METHODS: Patients with advanced NSCLC non-squamous carcinoma who were treated with a platinum-pemetrexed doublet as first-line combination chemotherapy were identified. Demographic, clinical, laboratory, and pathological data including the method of pathological diagnosis (morphology or IHC) was extracted from the clinical charts. The correlation between the various parameters and overall survival was evaluated. RESULTS: Lack of adenocarcinoma morphology, male sex, smoking history, and negative thyroid transcription factor 1 IHC were associated with worse prognosis and shorter overall survival in multivariate analysis. High white blood cell count, absolute neutrophil count, neutrophil to lymphocyte ratio, and low albumin levels were associated with shorter overall survival only in univariate analysis. CONCLUSION: Pulmonary adenocarcinoma has a better prognosis than NFA, regarding advanced NSCLC treated with platinum-pemetrexed combination chemotherapy. This distinction should be a stratification factor in clinical trials and a prognostic factor to consider in analysis of previous trials.

Hammertoe Correction With K-Wire Fixation Compared With Percutaneous Correction.

BACKGROUND: Kirschner wire (K-wire) fixation for correction of hammertoe deformity is the gold standard for hammertoe surgery fixation, the current study compares it to percutaneous surgery with 3M Coban dressings. METHODS: All hammertoe corrections performed were retrospectively reviewed. For the K-wire fixation group: resection arthroplasty of the proximal interphalangeal joint was performed and fixed with a K-wire. The percutaneous technique used involved percutaneous diaphyseal osteotomy of the middle and proximal phalanges combined with tendon release. The toes are then wrapped in 3M Coban dressing for 3 weeks. Follow-up duration, preoperative diagnosis, pin duration, concomitant procedures, visual analogue scale (VAS) pain, recurrence rates, and complications were reviewed and analyzed. A total of 352 patients (87 percutaneous/265 open), in whom 675 hammertoes (221 percutaneous/454 open) were corrected. There were 55.9% females, with an average age of 52.8 years, followed for 6 months. The percutaneous group had more diabetics and multiple toes surgery. RESULTS: Complications of the open surgery group included 5.5% pin migrations, 4.5% infections, and 8 (3%) had impaired wound healing. There were 6.2% recurrent deformities and 2.6% toes were revised. Malalignment was noted in 3.3% toes. Vascular compromise occurred in 0.5%, with 0.25% amputated. Complications of the percutaneous surgery group included 18.4% cases of impaired healing and 2.3% infection. Deep tissue dehiscence occurred in 4.5% of open surgery patients. VAS score decreased in both groups with a more pronounced decline in the percutanteous group (2 ± 2.1 vs 0.5 ± 1.6). The per toe infection rate of patients undergoing open hammertoe correction was 5.3% was significantly higher than with the percutaneous correction group, which was 2.2%. CONCLUSIONS: K-wire fixation and percutaneous surgery have similar abnormal healing rates, alignment and patient satisfaction but the latter technique has fewer infections. LEVELS OF EVIDENCE: Level III: Prospective case series with noncontamporenous cohorts.

Treatment of anterior tarsal tunnel syndrome through an endoscopic or open technique.

Anterior tarsal tunnel syndrome is often underdiagnosed, due to lack of clinical awareness and vague clinical presentation. Most often patients complain of pain located to the dorsum of the foot. The present study is a consecutive series of 13 patients treated according to a fixed protocol followed for a minimum of 24 months. A total of 12/13 cases presented with a bulge in the anterior part of the ankle or the dorsal foot and Tinel's sign was positive over it. Only half had decreased sensation. Surgical technique was either endoscopic or open. Endoscopy is preferable when compression is due to an osteophyte (4/13) or an isolated ganglion 2/13). In other cases presenting with synovitis (5/13) or unknown etiology (2/13) performing open surgery was deemed as safer. The American Orthopedic Foot and Ankle Society (AOFAS) hindfoot scores improved from an average of 55 ± 8 to 83 ± 11 at 12 months after surgery and 88 ± 10 at 24 months after surgery. The anterior tarsal tunnel syndrome accounts for approximately 5% of cases complaining of feet numbness, which undergo electromyographic and nerve conduction testing. Reports in the scientific literature are scarce, perhaps due to underdiagnosis, while it is amenable to surgical management. Clinical diagnosis supported by imaging studies demonstrated osteophytes, ganglions or localized synovitis. Endoscopic treatment can be performed safely provided a clear-cut single compressing element is identified.

Gelfoam first metatarsophalangeal replacement/interposition arthroplasty--a case series with functional outcomes.

Reported below are the functional results of a case-series of Gelfoam®-based first metatarsophalangeal total joint replacements using an interposition arthroplasty technique carried out between April 1997 and December 2007. All patients who underwent Gelfoam-based arthroplasty under the care of a single surgeon were included; outcome scores and complications were recorded. A total of 31 joints in 31 consecutive patients were followed for a mean duration of 64 (range 24-150) months, and the mean patient age at the time of operation was 48±9 (range 35-80) years. Hallux rigidus was the primary diagnosis in all of the cases except one in which a failed chevron ostetomy was the indication for treatment. The mean American Orthopaedic Foot & Ankle Society Hallux-Metatarsophalangeal-Interphalangeal score increased from an average of 35 pre-operatively to an average of 74 at final follow-up (range 67-100), with 20 (64.5%) joints rated good to excellent. One (3.5%) joint was fused 6 months after the arthroplasty procedure. Based on these results, we concluded that first MTPJ total joint Gelfoam™-based interpostion arthroplasty is a cheap alternative to other joint replacement systems for the MTP joint. The results appear similar to those achieved using more expensive devices.

Traumatic pathologies of the calcaneal peroneal tubercle.

The peroneal tubercle occurs in about one half of human feet. It size varies from a small nodule of less than 1mm height to a prominent spur up to 1cm in size. It had been noted to cause stenosing tenosynovitis of the peroneal tendons, especially in association with an accessory peroneal bone. The current manuscript describes two cases of symptomatic tenosynovitis developing after an ankle sprain with fracture of the peroneal tubercle. The tenosynovitis caused dysfunction of the peroneal tendons unresponsive to prolonged conservative therapy. Symptoms were resolved following surgical resection.

Economic consequences of operative delay for hip fractures in a non-profit institution.

This retrospective study evaluated the economic consequences of delaying hip fracture surgery in 191 elderly patients. Data was collected regarding fracture type, surgery, timing of surgery, background diseases, postoperative hospital stay, and complications. In addition, calculation of the drugs administered to the patients, cost of the surgery, blood transfusion, physiotherapy, laboratory examinations, radiographs, and any financial data were evaluated. Spending more resources for performing hip surgery within 48 hours is more cost-effective than delaying surgery past the third day.