Different leadless pacemakers working in harmony (Aveir in the atrium/Micra AV2 in the ventricle) in a patient with dextrocardia and double outlet right ventricle after high-risk infected device extraction.

INTRODUCTION: Patients with congenital heart disease are at increased risk for requiring cardiac pacing during their lifetime. METHODS: We present the first described case of using two leadless pacing systems manufactured by separate companies implanted within the same patient to provide atrial and ventricular pacing due to complex congenital anatomy. RESULTS: A 27-year-old male with dextrocardia with double outlet right ventricle, subaortic ventricular septal defect, and pulmonary stenosis status-post pulmonary valve replacement complicated by ventricular pacing dependence and subsequent atrial pacing dependence after atriotomy-based atypical flutter ablation developed recurrent mediastinitis and pocket infection with erosion despite prolonged antibiotic treatment. Due to atrial and ventricular pacing dependence, a comprehensive congenital care team concluded the need for lead extraction and replacement of pacemaker via leadless peacemaking device. Laser-lead extraction and temporary atrial pacemaker placement was performed. Afterward, a transesophageal echocardiogram guided implantation of both a Micra AV 2 (Medtronic) leadless pacemaker in the interventricular septum within the right ventricle and an Aveir (Abbott) leadless pacemaker in the superior base of the right atrial appendage was performed with successful pacing. Although there is no communication between these devices, atrial-mechanical ventricular pacing was reliable with good implant thresholds, impedances and sensing from both devices. CONCLUSION: Our case demonstrates the feasibility of using dual leadless pacing modalities to simultaneously pace someone at complex, prohibitive risk for temporary permanent or permanent pacemaker devices.

Hypertrophic Cardiomyopathy in Youth Athletes: Successful Screening With Point-of-Care Ultrasound by Medical Students.

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) is a life-threatening genetic cardiovascular disease that often goes undetected in young athletes. Neither history nor physical examination are reliable to identify those at risk. The objective of this study is to determine whether minimally trained medical student volunteers can use ultrasound to screen for HCM. METHODS: This was a prospective enrollment of young athletes performed at 12 area high schools and three area colleges, between May 2012 and August 2013. All participants underwent point-of-care ultrasound performed screening for HCM by trained medical students and reviewed by a pediatric cardiologist. An interventricular septum to left ventricular posterior wall ratio greater than 1.25 was considered to be abnormal (positive screen). RESULTS: A total of 2332 participants were enrolled. There were 137 (5.8%) with a positive screening for HCM, of which 7 (5.1%) were confirmed to have HCM by a pediatric cardiologist. In a small cohort with positive screen for HCM, there was a 100% sensitivity (95% confidence interval, 59.04 to 100%) and 4.86% (95% confidence interval, 1.98 to 9.76%) positive predictive value of for having HCM. CONCLUSIONS: Volunteer medical students, using point-of-care ultrasound, were able to effectively screen for HCM in young athletes.

Exploratory use of intraprocedural transesophageal echocardiography to guide implantation of the leadless pacemaker.

Background: Fluoroscopy is the standard tool for transvenous implantation of traditional and leadless pacemakers (LPs). LPs are used to avoid complications of conventional pacemakers, but there still is a 6.5% risk of major complications. Mid-right ventricular (RV) septal device implantation is suggested to decrease the risk, but helpful cardiac landmarks cannot be visualized under fluoroscopy. Transesophageal echocardiography (TEE) is an alternative intraprocedural imaging method. Objective: The purpose of this study was to explore the spatial relationship of the LP to cardiac landmarks via TEE and their correlations with electrocardiographic (ECG) parameters, and to outline an intraprocedural method to confirm mid-RV nonapical lead positioning. Methods: Fifty-six patients undergoing implantation of LP with TEE guidance were enrolled in the study. Device position was evaluated by fluoroscopy, ECG, and TEE. Distances between the device and cardiac landmarks were measured by TEE and analyzed with ECG parameters with and without RV pacing. Results: Mid-RV septal positioning was achieved in all patients. TEE transgastric view (0°-40°/90°-130°) was the optimal view for visualizing device position. Mean tricuspid valve-LP distance was 4.9 ± 0.9 cm, mean pulmonary valve-LP distance was 4.2 ± 1 cm, and calculated RV apex-LP distance was 2.9 ± 1 cm. Mean LP paced QRS width was 160.8 ± 28 ms and increased from 117.2 ± 34 ms at baseline. LP RV pacing resulted in left bundle branch block pattern on ECG and 37.8% QRS widening by 43.5 ± 29 ms. Conclusion: TEE may guide LP implantation in the nonapical mid-RV position. Further studies are required to establish whether this technique reduces implant complications compared with conventional fluoroscopy.

A 70-Year-Old Man With Relapsed CNS Lymphoma Has Incidental Finding of Right Atrial Mass.

CASE PRESENTATION: A 70-year-old man was admitted to the hospital for planned chemotherapy for recently diagnosed CNS lymphoma. His medical history included follicular lymphoma (achieved remission 1 year prior with chemotherapy) and tonic-clonic seizure 1 month prior to admission, which led to his eventual biopsy-confirmed diagnosis of CNS lymphoma. Physical examination revealed temperature 36.4 °C, heart rate of 60 beats/min, BP of 160/81 mm Hg, and 98% oxygen saturation on room air. Neurologic condition, including mental status examination, was normal. His cardiac examination revealed regular rate and rhythm with normal first and second heart sounds without murmurs, rubs, or gallops. The remainder of the examination was unremarkable. Review of systems noted progressive and intermittent confusion prior to his seizure. He denied any shortness of breath, dyspnea on exertion, orthopnea, lower extremity edema, palpitations, or syncope. Laboratory data were unremarkable.

Photorefractive keratectomy after late traumatic LASIK flap loss.

PURPOSE: To present a case of photorefractive keratectomy (PRK) after late traumatic LASIK flap loss. METHODS: The initial LASIK procedure was performed in 2003 with a Moria M2 microkeratome and NIDEK EC-5000 excimer laser using a 5.0/9.0-mm aspheric ablation pattern, resulting in 20/20(+) uncorrected distance visual acuity (UDVA) and plano refraction. Traumatic flap loss of the right eye occurred in 2007. The patient was treated for the trauma, and PRK for -5.00 -1.25 × 090° was performed 2 months later. RESULTS: Posttraumatic flap loss UDVA was 20/200 in the right eye, with corrected distance visual acuity (CDVA) of 20/25(+2). After PRK with mitomycin C (MMC), UDVA was 20/15 2 months postoperatively and was maintained through the last postoperative follow-up in 2010 (approximately 3 years after PRK). CONCLUSIONS: Treating a patient with traumatic LASIK flap loss can be done by careful, conservative treatment of the abrasion followed by correction of the refractive error using PRK with MMC.

Circadian rhythms in Neurospora crassa: Downstream effectors.

The circadian rhythm in Neurospora crassa is exhibited as alternating areas of conidiating and non-conidiating mycelia growth. A significant role in this circadian rhythm is played by the frq (frequency) and wc (white-collar) genes, comprising the "FWC" oscillator. Strains lacking the FWC can be restored to rhythmicity, which has been attributed to a second oscillator, called the FLO (frq-less oscillator). This study reports additional conditions that allow this rhythmicity to occur. Rhythmicity was restored to mutants lacking either the frq, or wc-1, or wc-2 genes in D/D (constant darkness) or L/L (constant light) by the addition of low levels of menadione, a known stimulator of ROS (reactive oxygen species). Additional studies are reported on the rhythm effects from caffeine, a known cAMP phospho-diesterase inhibitor as well as the effects from mutations in the csp-1 gene, the rco-1 gene, and other genes. A theme ties all of these "downstream effects" together, i.e., they affect either components thought to be part of the conidiation process itself, or the RAS-cAMP-protein kinase pathway. Since mutations in these components unexpectedly had rhythm effects, this suggests that these components may be good candidates for some part of the frq-less oscillator.