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We report a novel use of transcatheter aortic valve replacement (TAVR) for valve-in-valve tricuspid valve replacement. A man in his 50s with prohibitive risks for surgical intervention underwent this procedure to improve severe, symptomatic tricuspid stenosis. Though current literature is limited to case reports, the Valve-in-Valve International Database (VIVID) reports similar mortality rates between surgical and transcutaneous replacement. As a novel, off-label procedure, there is limited operator experience. Nonetheless, in non-operative or high-risk patients, similar outcomes are noted in between transcatheter tricuspid valve replacement and surgical replacement. This registry sets the framework for further studies with the possibility of observing outcomes as operator experience increases, while highlighting the feasibility of the procedure.

INTRODUCTION Limited data are available about the outcomes of transcatheter mitral valve replacement (TMVR) using transseptal approach in patients with prior mitral valve repair (valve-in-ring) or replacement (valve-in-valve) (TMViVR) and on modes of the prior surgical valve failures. We report our tertiary center TMVR experience in high surgical risk patients with prior mitral valve repair or replacement. METHODS From December 2016 to January 2020, patients with symptomatic severe mitral valve stenosis and/or insufficiency at increased redo surgical risk were included. TMViVR was performed off-label with Sapien S3 valve (Edwards Lifesciences). Patients were followed within 30-days and 1-year from the procedure. RESULTS Twenty-seven patients underwent transcatheter mitral valve-in-valve (n = 21) or valve-in-ring (n = 6) replacement. Mean ± SD age was 71.8 ± 11 years with Society of Thoracic Surgeons' calculated mortality 7.1 ± 4.6%. The etiology of valve failure was stenosis in 17 (63%) patients, insufficiency in 4 (14.8%) patients, and both in 6 (22.2%) patients. TMViVR technical success was 100% in all patients. Left ventricular outflow track (LVOT) obstruction was observed in only one (3.7%) patient. Zero patients had moderate or severe central mitral valve regurgitation or paravalvular leak. All patients had symptomatic improvement at 30 days. The mean transmitral diastolic pressure gradient decreased from 14.1 ± 4.6 to 6.9 ± 4.6 mm Hg (p

Treatment advances for severe symptomatic aortic stenosis including transcatheter and open surgical valve replacement have improved patient survival, length of stay, and speed to recovery. However, paravalvular regurgitation (PVR) is occasionally seen and when moderate or greater in severity is associated with an at least 2‐fold increase in 1 year mortality. While several treatment approaches focused on single‐jet PVR have been described in the literature, few reports describe multijet PVR. Multijet PVR can successfully be treated with a variety of catheter‐based options including valve‐in‐valve (ViV) transcatheter aortic valve replacement (TAVR). We present two patients with at least moderate PVR following aortic valve replacement who were successfully treated with ViV TAVR along with a review of literature highlighting our rationale for utilizing each management approach. Multijet PVR can be treated successfully with ViV TAVR, but additional options such as self‐expanding occluder devices and bioprosthetic valve fracture have a role as adjunctive treatments to achieve optimal results. The etiology of multijet PVR can differ between patients, this heterogeneity underscores the paucity of data to guide treatment strategies. Therefore, successful treatment of multijet PVR requires familiarity with available therapeutic options to achieve optimal results and, by extension, decrease patient mortality.

Patients with end-stage heart failure with reduced ejection fraction requiring mechanical support while awaiting heart transplant present a clinical dilemma. Intra-aortic balloon pump (IABPs) provide a modest improvement in hemodynamics and are easy to implant. Left axillary IABP implantation allows patients to engage in daily physical activity pre-transplant. We present a case of a patient awaiting heart transplant with a left axillary IABP that prolapsed above the aortic valve in the ascending aortic root requiring immediate removal. We describe our multi-modal imaging evaluation, and technique to safely remove the IABP and replace a new one into the same left axillary access while preserving vascular access.

Intra-aortic balloon pump via the axillary approach has been increasingly utilized to facilitate physical rehabilitation prior to definitive heart failure therapy. There is a high risk of device fracture with loss of arterial accessibility. Three cases are presented that demonstrate innovative arteriotomy hemostasis techniques for malfunctioning axillary intra-aortic balloon pumps. (Level of Difficulty: Intermediate.), Graphical abstract, Intra-aortic balloon pump via the axillary approach has been increasingly utilized to facilitate physical rehabilitation prior to definitive…

Objective Little is known regarding the specific ways personal protective equipment (PPE) has been used and reused during the coronavirus disease 2019 (COVID‐19) pandemic. The objective of this study was to evaluate the patterns of PPE use and the impact of PPE availability on the attitudes and well‐being of an international population of healthcare workers. Methods This was an online, cross‐sectional survey of healthcare workers. The survey was disseminated internationally using social media, specialty society list‐serves, and email augmented by snowball sampling to healthcare workers who provided direct care to patients with suspected or confirmed COVID‐19. The survey was conducted between April 13 and May 1, 2020. The primary outcome was self‐reported PPE use during aerosol‐generating medical procedures. Other outcomes included PPE use during care for respiratory patients in general, PPE reuse, PPE decontamination, and healthcare worker impressions related to their work and the pandemic. Results A total of 2227 healthcare workers from 23 countries completed the survey. The N95 was the most common respirator among the 1451 respondents who performed aerosol‐generating procedures (n = 1050, 72.3%). Overall, 1783 (80.1%) of providers reported general reuse of PPE, which was similar across US regions but less common in Canada, Italy, and Spain. The most commonly reused item of PPE was the N95 respirator, with the majority of respondents who reused PPE reporting N95 reuse (n = 1157, 64.9%). Of the 1050 individuals who wore an N95 mask while performing an aerosol‐generating medical procedure, 756 (72%) reported re‐using an N95, and 344 (45.5%) reported reuse for >3 days. Qualitative results identified several common themes, including (1) lack of availability of PPE, (2) fear and anxiety as a result of inadequate PPE, (3) potential exposure to family members, and (4) concerns regarding workload and pay. Conclusions This international survey of healthcare workers found that N95 respirators were commonly used to care for patients with respiratory symptoms with and without aerosol‐generating medical procedures. Healthcare workers reported an unprecedented need to reuse PPE that was designed for single‐use, specifically the N95 respirator. The reuse of PPE increased the perceived risk for COVID‐19 infection and harmed mental health.

Tricuspid valve regurgitation (TR) can be associated with poor prognosis. Transcatheter valve technology was adopted to treat the upstream effects of severe TR by placing a transcatheter valve in the inferior vena cava (IVC). In this study, we report off-label transcatheter valve implantation into the stented IVC in patients with severe TR for compassionate use. From September 2018 to February 2020, 6 inoperable patients with severe TR who failed medical treatment underwent percutaneous caval valve implantation (CAVI). Severity of TR was confirmed by intraoperative transesophageal echocardiography. Z-stents (Cook, Inc., Bloomington, IN, USA) were placed in the proximal IVC, and then a transcatheter valve was deployed in the suprahepatic cava without rapid pacing. Six patients, 2 females and 4 males, with a mean ± SD age of 74.7 ± 8.0 years were included. The procedure was successfully performed in all 6 patients (100%) employing a 29-mm SAPIEN 3 valve (Edwards Lifesciences, Irvine, CA, USA) with supranominal volume. No procedural complication was detected. At 30 days, TR improved from severe to trace in 1 patient, to mild-moderate in 3 patients, and 2 patients remained with severe TR. Among patients with improved TR, left ventricular ejection fraction increased from 47.5% ± 18.5% to 55% ± 20.4% ( P = 0.014). No patient had readmission at 30 days. Four patients needed rehospitalization within 6 months. Percutaneous CAVI is feasible and can be considered as a short-term palliative measure in patients with severe TR. CAVI can improve TR and potentially improve cardiac output in selected patients.

Introduction Lower transcatheter aortic valve replacement (TAVR) pressure gradients have been reported after implantation of self-expanding valves compared with balloon-expandable valves; however, there is a paucity of data on the relationship between invasively measured transvalvular pressure gradients and Doppler-derived measurements. Methods From September 2013 to September 2018, patients with native aortic valve stenosis who had both intraoperative invasive and postoperative echocardiography transvalvular pressure gradients were included for analysis. We used parametric and nonparametric statistics to compare aortic gradients within and between groups. Results Of 171 patients, 152 (88.9%) patients had TAVR with a balloon-expandable valve and 19 (11.1%) with a self-expanding valve. Among all patients, the invasive aortic gradient was 7.8 ± 3.2 mmHg and the Doppler-derived aortic gradient was 11.0 ± 4.5 mmHg (p p p = 0.18). Conclusions Balloon-expandable valves were associated with lower invasive measurements versus post-TAVR Doppler gradients, while results were inconclusive regarding self-expanding valves.

Introduction When transcatheter aortic valve replacement (TAVR) was introduced, pre-implantation balloon aortic valvuloplasty (BAV) was a routine part of the procedure. Smaller device profiles have resulted in selective use of BAV; however, there is a paucity of data about the trend in use of direct TAVR and the safety of this strategy. Methods All patients who underwent TAVR at a Veterans Affairs Medical Center from September 2013 to November 2016 were included in this retrospective analysis. We reviewed angiography films and verified with procedure reports to assess if direct TAVR was performed. Troponin T was assessed within 72 h after the TAVR. Multivariate analysis examined the association between direct TAVR and periprocedural myocardial infarction (MI) or 1-year mortality. Results Overall, 207 patients were available for analysis. The mean follow-up was 13.3 months. A balloon-expandable valve was used 93.2% of the time, and 35.3% of patients were treated with conscious sedation. Periprocedural MI or 1-year mortality occurred in 12.5% of the direct TAVR group versus 18.3% of the pre-implantation BAV group (p = 0.30). After controlling for potential confounding variables, direct TAVR was not associated with periprocedural MI or 1-year mortality. Conclusions Direct TAVR appears to be safe and is not associated with periprocedural MI or 1-year mortality. With current generation devices, this strategy can be considered for most patients undergoing TAVR.

Introduction Hemodynamic measurements can assess for paravalvular aortic regurgitation after transcatheter aortic valve replacement (TAVR). This study compared the utility of different invasive hemodynamic measures in providing prognostic information. Methods This retrospective observational study of TAVR patients at a Veterans Hospital assessed aortic regurgitation index, diastolic delta, pulse pressure, and heart rate adjusted diastolic delta obtained at valve implantation. The primary outcome was total mortality. Results Overall, 151 patients underwent TAVR. Immediately after implantation, mean aortic regurgitation index was 31 ± 8.6, mean diastolic delta was 38 ± 9.8 mmHg, mean pulse pressure was 67 ± 18 mmHg, and mean heart rate adjusted diastolic delta was 47 ± 14.3 mmHg/beats per minute. Two percent of patients had ≥ moderate paravalvular aortic regurgitation by postoperative transthoracic echocardiography. Total mortality was 15.2% at a mean follow-up of 12.7 ± 9.2 months. Aortic regurgitation index 60 vs. ≤60 mmHg were not associated with total mortality. However, total mortality was 50% for heart rate adjusted diastolic delta

Pressure measurements are frequently obtained during transcatheter aortic valve replacement (TAVR). Historically, pressures have been used to diagnose paravalvular aortic regurgitation ([1][1]). Our aim was to explore whether a modified hemodynamic assessment could provide long-term prognostic

We adopted e-consults within an active referral management (ARM) process for our Veterans Health Administration (VHA) outpatient cardiology clinic to reduce clinic wait times.Prospective multiphase cohort study.Our ARM process consisted of reviewing all incoming consult requests for our outpatient clinic and triaging the requests to either an e-consult or a clinic visit. The primary outcome was wait time for an appointment in our clinic.Median wait time prior to the ARM process was 24 days. After implementation of the ARM process, wait times decreased to 13 days (46% reduction). Approximately 60% of incoming consults could be triaged into e-consults, predominantly by managing stable diseases or minor symptoms.E-consults and ARM of clinical referrals were effective at reducing wait times for our outpatient VHA cardiology clinic. The majority of clinical referrals could be handled through an e-consult and did not require an in-person clinic visit.

Training in quality improvement (QI) is a pillar of the next accreditation system of the Accreditation Committee on Graduate Medical Education and a growing expectation of physicians for maintenance of certification. Despite this, many postgraduate medical trainees are not receiving training in QI methods. We created the Fellows Applied Quality Training (FAQT) curriculum for cardiology fellows using both didactic and applied components with the goal of increasing confidence to participate in future QI projects.Fellows completed didactic training from the Institute for Healthcare Improvement's Open School and then designed and completed a project to improve quality of care or patient safety. Self-assessments were completed by the fellows before, during, and after the first year of the curriculum. The primary outcome for our curriculum was the median score reported by the fellows regarding their self-confidence to complete QI activities. Self-assessments were completed by 23 fellows. The majority of fellows (15 of 23, 65.2%) reported no prior formal QI training. Median score on baseline self-assessment was 3.0 (range, 1.85-4), which was significantly increased to 3.27 (range, 2.23-4; P = 0.004) on the final assessment. The distribution of scores reported by the fellows indicates that 30% were slightly confident at conducting QI activities on their own, which was reduced to 5% after completing the FAQT curriculum. An interim assessment was conducted after the fellows completed didactic training only; median scores were not different from the baseline (mean, 3.0; P = 0.51).After completion of the FAQT, cardiology fellows reported higher self-confidence to complete QI activities. The increase in self-confidence seemed to be limited to the applied component of the curriculum, with no significant change after the didactic component.

Summary Background Few studies have examined the efficacy of drug-eluting stents (DES) for reducing aortocoronary saphenous vein bypass graft (SVG) failure compared with bare-metal stents (BMS) in patients undergoing stenting of de-novo SVG lesions. We assessed the risks and benefits of the use of DES versus BMS in de-novo SVG lesions. Methods Patients were recruited to our double-blind, randomised controlled trial from 25 US Department of Veterans Affairs centres. Eligible participants were aged at least 18 years and had at least one significant de-novo SVG lesion (50–99% stenosis of a 2·25–4·5 mm diameter SVG) requiring percutaneous coronary intervention with intent to use embolic protection devices. Enrolled patients were randomly assigned, in a 1:1 ratio, by phone randomisation system to receive a DES or BMS. Randomisation was stratified by presence or absence of diabetes and number of target SVG lesions requiring percutaneous coronary intervention (one or two or more) within each participating site by use of an adaptive scheme intended to balance the two stent type groups on marginal totals for the stratification factors. Patients, referring physicians, study coordinators, and outcome assessors were masked to group allocation. The primary endpoint was the 12-month incidence of target vessel failure, defined as the composite of cardiac death, target vessel myocardial infarction, or target vessel revascularisation. The DIVA trial is registered with ClinicalTrials.gov, number NCT01121224. Findings Between Jan 1, 2012, and Dec 31, 2015, 599 patients were randomly assigned to the stent groups, and the data for 597 patients were used. The patients' mean age was 68·6 (SD 7·6) years, and 595 (>99%) patients were men. The two stent groups were similar for most baseline characteristics. At 12 months, the incidence of target vessel failure was 17% (51 of 292) in the DES group versus 19% (58 of 305) in the BMS group (adjusted hazard ratio 0·92, 95% CI 0·63–1·34, p=0·70). Between-group differences in the components of the primary endpoint, serious adverse events, or stent thrombosis were not significant. Enrolment was stopped before the revised target sample size of 762 patients was reached. Interpretation In patients undergoing stenting of de-novo SVG lesions, no significant differences in outcomes between those receiving DES and BMS during 12 months of follow-up were found. The study results have important economic implications in countries with high DES prices such as the USA, because they suggest that the lower-cost BMS can be used in SVG lesions without compromising either safety or efficacy. Funding US Department of Veterans Affairs Cooperative Studies Program.

Background: Electronic consultations (e-consults) are a novel approach to patient care that may improve access to specialty care by reducing the burden on outpatient clinics. We adopted e-consults within an active referral management (ARM) process for our Veterans Health Administration (VHA) outpatient cardiology clinic to reduce clinic wait times. Methods: Our ARM process consisted of reviewing all incoming consult requests for our outpatient clinic and triaging the requests to either an e-consult or a clinic visit. This occurred in two phases, triaged by physician alone in the first phase (11/1/15 to 10/30/16) and by a non-physician provider/provider dyad (11/1/16 to 3/1/17) in the second phase. Results: The primary outcome was wait time for an appointment in our clinic. A secondary analysis of consult requests was reviewed to determine the proportions of ordering specialties, reasons for consults, and the result of the ARM triage. The median wait time for our clinic prior to adopting e-consults and the ARM process was 24 days. In phase 1, we observed 20 weeks of wait times below the median and the wait time was calculated to be 13 days (46% reduction). In phase 2, we observed a significant increase in both overall consult volume and in wait times. Approximately 60% of incoming consults could be triaged into e-consults, predominantly by managing stable diseases or minor symptoms. Conclusions: E-consults and ARM of clinical referrals were effective at reducing wait times for outpatient VHA cardiology clinic. The majority of clinical referrals could be handled through e-consult and did not require an in-person clinic visit.

Saphenous venous graft (SVG) pseudoaneurysms are a rare complication of coronary artery bypass grafting (CABG). An 85-year-old man with CABG and a distal SVG stent presented with dyspnea. Chest computed tomography (CT) revealed a large partially thrombosed pseudoaneurysm at the distal SVG with stent fracture. Endoluminal exclusion of the distal SVG pseudoaneurysm using a covered stent was performed. Follow-up chest CT and angiography showed persistent pseudoaneurysm filling and enlargement. The SVG proximal to the pseudoaneurysm was embolized with coils to reduce rupture risk. Following embolization, the patient’s left ventricular ejection fraction was moderately depressed but the patient remained stable and was discharged. Learning objective: Saphenous venous graft pseudoaneurysms are a rare post-operative complication of coronary artery bypass graft procedures with a risk of impending rupture if left untreated. Fracture of a vein graft stent is an even further unique etiology of pseudoaneurysms. Covered stents are a practical therapeutic option for the treatment of vein graft pseudoaneurysms, especially in high risk patients who are not surgical candidates.>

Patients with advanced liver disease have a high prevalence of cardiovascular risk factors, but many of them are asymptomatic. Cardiovascular risk stratification prior to liver transplant can be done by dobutamine stress echocardiography, stress myocardial perfusion imaging, cardiac computer tomography, and coronary angiography, but there are no clear recommendations regarding what method should be used and who should be screened. Because of this and because of inherent risk profile in this population, the variations in practice are significant. Careful screening and rigorous management of cardiovascular risk factors are important to ensure optimal cardiovascular outcomes in the immediate post-transplantation period and in the long term as well.

Background: Formal training in quality improvement (QI) methods is sporadic in medical educational settings. QI is a growing expectation for individual professional certifications and facility accreditations; future physicians will need to understand and apply QI methods as part of their practice. We developed a curriculum with both didactic and applied components to teach QI methods to cardiology fellows. Methods: The Fellows Applied Quality Training (FAQT) curriculum started in July 2013 with an initial cohort of 23 postgraduate trainees in general and subspecialty cardiovascular medicine fellowships. The FAQT is a multifaceted QI curriculum consisting of online learning modules, didactic training, and the start-to-finish completion of a team-based, self-directed quality improvement project under supervision of a faculty mentor. Trainees completed selected modules from the Institute of Healthcare Improvement Open School including basic terminology and background of QI methods. Trainees were assigned to small groups and challenged to identify an area in need, design an intervention to improve quality or safety, select an appropriate metric to measure, determine how to acquire the necessary data, implement their plan, analyze data to measure their success, and formally present the results. Prior to, during, and at the completion of the FAQT, trainees completed the 13 question self-assessment from the Quality Assessment and Improvement Curriculum. This assessment asks participants to rate their confidence to perform QI activities independently. The primary outcome of our investigation was an increase in the median confidence score reported on a 4 point scale (1=not at all confident, 2=slightly confident, 3=moderately confident, 4=extremely confident) compared by Wilcoxon signed rank test. Results: Prior to the FAQT, 15 trainees reported no prior formal QI training. Of those with prior training, 4 were practical and 4 had only didactic training. At baseline, the median score given on the assessment was 3.0. After completion of online training modules, the median score did not increase (3.0, p=0.51). At the conclusion of the self-directed projects, average confidence was higher (3.27, p=0.004). The proportion of fellows reporting they were “extremely” confident about using quality assessment and improvement in your future career increased from15% to 50% while the proportion reporting “slight” confidence decreased from 30% to 5%. Conclusion: At our institution, the majority of post-graduate medical trainees had no formal exposure to QI training. After completing a curriculum with practical application of QI methods, trainees reported an increase in their self-confidence to independently conduct QI; no increase was observed with didactic training alone.

Enhanced external counterpulsation (EECP) is a noninvasive technique for treatment of symptomatic coronary artery disease in patients not amenable to revascularization procedures. However, the mechanisms underlying the benefits of EECP remain unknown. We hypothesized that decreases in arterial stiffness and aortic wave reflection are a therapeutic target for EECP. Patients with coronary artery disease and chronic angina pectoris were randomized (2:1 ratio) to 35 1-hour sessions of EECP (n = 28) or sham EECP (n = 14). Central and peripheral arterial pulse-wave velocity and aortic wave reflection (augmentation index) were measured using applanation tonometry before, and after 17 and 35 1-hour treatment sessions. Wasted left ventricular pressure energy and aortic systolic tension-time index, markers of left-ventricular myocardial oxygen demand, were derived from the synthesized aortic pressure wave. Exercise duration, anginal threshold, and peak oxygen consumption were measured using a graded treadmill test. Central arterial stiffness and augmentation index were decreased after 17 and 35 sessions in the treatment group. Measurements of peripheral arterial stiffness were decreased after 35 sessions in the treatment group. Changes in aortic pressure wave reflection resulted in decreased measurements of myocardial oxygen demand and wasted left ventricular energy. No changes in central or peripheral arterial stiffness were observed in the sham group. Furthermore, measurements of exercise capacity were improved in the EECP group but unchanged in the sham group. In conclusion, EECP therapy decreases central and peripheral arterial stiffness, which may explain improvements in myocardial oxygen demand in patients with chronic angina pectoris after treatment.

Background— Mechanisms responsible for anti-ischemic benefits of enhanced external counterpulsation (EECP) remain unknown. This was the first randomized sham-controlled study to investigate the extracardiac effects of EECP on peripheral artery flow-mediated dilation. Methods and Results— Forty-two symptomatic patients with coronary artery disease were randomized (2:1 ratio) to thirty-five 1-hour sessions of either EECP (n=28) or sham EECP (n=14). Flow-mediated dilation of the brachial and femoral arteries was performed with the use of ultrasound. Plasma levels of nitrate and nitrite, 6-keto-prostaglandin F 1α , endothelin-1, asymmetrical dimethylarginine, tumor necrosis factor-α, monocyte chemoattractant protein-1, soluble vascular cell adhesion molecule, high-sensitivity C-reactive protein, and 8-isoprostane were measured. EECP increased brachial (+51% versus +2%) and femoral (+30% versus +3%) artery flow-mediated dilation, the nitric oxide turnover/production markers nitrate and nitrite (+36% versus +2%), and 6-keto-prostaglandin F 1α (+71% versus +1%), whereas it decreased endothelin-1 (−25% versus +5%) and the nitric oxide synthase inhibitor asymmetrical dimethylarginine (−28% versus +0.2%) in treatment versus sham groups, respectively (all P P P Conclusions— Our findings provide novel mechanistic evidence that EECP has a beneficial effect on peripheral artery flow-mediated dilation and endothelial-derived vasoactive agents in patients with symptomatic coronary artery disease.

Myocardial injury after transcatheter aortic valve replacement (TAVR) is a potential complication following the procedure. Cardiac enzyme elevation after TAVR has been associated with increased adverse events including cardiac mortality. The impact of pre-TAVR balloon aortic valvuloplasty (BAV) and

Cardiovascular disease is associated with chronic low-level inflammation, as evidenced by elevated circulating proinflammatory cytokines. Experimental evidence suggests that inflammation can be suppressed under conditions of high shear stress. This study was conducted to examine the effects of enhanced external counterpulsation (EECP), a noninvasive therapy that increases endothelial shear stress, on circulating levels of inflammatory biomarkers and adhesion molecules in patients with angina pectoris. Twenty-one patients were randomly assigned to either 35 1-hour treatments at cuff pressures of 300 mm Hg (EECP; n=12) or 75 mm Hg (sham; n=9). Plasma tumor necrosis factor-alpha, monocyte chemoattractant protein-1, and soluble vascular cell adhesion molecule-1 were measured before and after 35 1-hour sessions of treatment or sham. Patients in the EECP group demonstrated reductions in tumor necrosis factor-alpha (6.9+/-2.7 vs 4.9+/-2.5 pg/ml, p

A major protein in the postsynaptic density fraction is α-CAM kinase II, the α-subunit of the Ca2+/calmodulin-dependent protein kinase. Autophosphorylation of the postsynaptic density-associated CaM kinase II is likely to be a crucial event in the induction of activity-dependent synaptic modification. This study focuses on the regulation and consequences of Ca2+-independent autophosphorylation of the enzyme. In isolated postsynaptic densities, a sub-stochiometric level of autophosphorylation in the presence of Ca2+ is sufficient to trigger maximal Ca2+-independent autophosphorylation of α-CaM Kinase II. A major fraction of the sites phosphorylated in the absence of Ca2+ can be dephosphorylated by the endogenous phosphatase activity in the preparation. Ca2+-independent autophosphorylation is correlated with a drastic decrease in calmodulin binding to postsynaptic densities. This may represent a physiological mechanism that lowers the calmodulin trapping capacity of the organelle, thus increasing the availability of calmodulin to other elements within a spine.

We present the growth and properties of asymmetric triangular quantum wells (ATQWs) involving GaAs/Al 0.3 Ga 0.7 As and strained In x Ga 1-x As by molecular beam epitaxy. Compositional grading was approximated using a superlattice technique and varying the thickness of the ternary material in each «cell». GaAs/AlGaAs ATQWs exhibit narrow low temperature photoluminescence (PL) linewidths of 2 meV for an 11 period 675 A well width. Sub-meV linewidths are obtained for both InGaAs/GaAs rectangular and asymmetric triangular single QWs, indicative of high quality InGaAs material as well as smooth heterointerfaces

Pregnant patients with mechanical valves require anticoagulation. The risk of bleeding and embryopathy associated with oral anticoagulation must be weighed against the risk of valve thrombosis. In the presence of a mechanical valve thrombosis, an appropriate treatment modality must be selected, as it is critical for the health of mother and fetus. In this review, we present a pregnant patient with mechanical valve thrombosis (MVT) who underwent thrombolytic therapy, subsequent anticoagulation according to available guidelines, and delivered a healthy baby at full term. Copyright © 2007 Wiley Periodicals, Inc.

Electron micrographs of rotary shadowed replicas of α-Ca 2+ /calmodulin-dependent protein kinase II reveal a flower-shaped multimeric molecule with a central particle surrounded by 8–10 smaller peripheral particles. Peripheral particles are attached to the central particle by thin arms or “linkers.” Movement of peripheral particles to contact each other for autophosphorylation is likely to involve these linkers. It has generally been accepted that the segment 317–328 of the α-subunit constitutes the linker domain. In the present study we test this assumption by generating a mutant lacking the proposed sequence. The mutant has biochemical and morphological properties similar to those of the wild type, and a thin linker is occasionally observed in replicas from either type. The results indicate that the deleted sequence does not correspond to the linker domain. This conclusion, combined with observations from two recent studies which identify the C-terminal domain involved in oligomerization, narrows down the location of the linker domain within the sequence 330–354.

The first measurement of indium desorption activation energy (DAE) from InP layers in gas‐source molecular‐beam epitaxy is being reported. A thick layer of InP (1.5 μm) was grown on GaAs to relax the strain induced from the lattice mismatch. Temperature programmed desorption (TPD) and laser induced fluorescence (LIF) were used to monitor the temperature dependent indium desorption rate from phosphorus stabilized InP surface. From the TPD experiment, Arrhenius plots of the indium LIF signal versus 1000/Tsub, show that the indium DAE was 4.49±0.15 eV. This value is 1.4 eV higher than our previous measurement of indium DAE from InAs.

Introduction Fractional flow reserve (FFR) is recommended by society guidelines for assessment of the hemodynamic significance of intermediate coronary lesions when non-invasive evidence of myocardial ischemia is unavailable. However, the prevalence of FFR usage in current practice and how FFR values impact revascularization decisions are not well known. Methods At a single-center Veterans Administration Hospital, all subjects referred for coronary angiography for any indication from the period from May 2012 until January 2014 were prospectively entered into a database. FFR was measured in all intermediate coronary lesions (30–70% stenosis). Based on the FFR results, the lesions were categorized into 3 different groups: FFR > 0.80 (non-ischemic), FFR 0.75–0.80 (gray zone), and FFR

Introduction We aimed to assess if ranolazine would improve angina symptoms among patients with documented myocardial ischemia. Methods Eligible subjects had chronic stable angina and at least one coronary stenosis with fractional flow reserve (FFR) ≤0.80 or at least one chronic total occlusion (CTO) without attempted revascularization. Subjects were randomized to oral ranolazine 500 mg twice daily for 1 week, then ranolazine 1000 mg twice daily for 15 weeks versus matching placebo. The primary end point was change in angina at 16 weeks as assessed by the Seattle Angina Questionnaire (SAQ). Results Between September 2014 and January 2016, 25 subjects were randomized to ranolazine versus 25 to placebo. The most common reason for eligibility was CTO (72%), while the remainder had myocardial ischemia documented by low FFR. The mean FFR was 0.57 ± 0.12. Sixty-eight percent of subjects were on two or more anti-angina medications at baseline. Study medication was discontinued in 32% (eight of 25) of the ranolazine group versus 36% (nine of 25) of the placebo group. By intention-to-treat, 46 subjects had baseline and follow-up SAQ data completed. Ranolazine was not associated with an improvement in angina compared with placebo at 16 weeks. The results were similar among 33 subjects that completed study medication. The incidence of ischemia-driven hospitalization or catheterization was 12% (three of 25) of the ranolazine group versus 20% (five of 25) in the placebo group (p > 0.05). Conclusions In subjects with chronic stable angina and documented myocardial ischemia, ranolazine did not improve angina symptoms at 16 weeks. Funding Gilead. Clinical trial registration The study was registered at ClinicalTrials.gov (NCT02265796).