Use of Spinal Cord Stimulators in Patients With Pacemakers or Implantable Cardiac Defibrillators: A Review of Documented Accounts of Interference.

OBJECTIVES: To assess the currently available evidence regarding associations between spinal cord stimulator (SCS) lead type, clinical indications for device placement, and interference between SCSs and cardiac pacemakers (CPMs)/implantable cardioverter-defibrillators (ICDs). STUDY DESIGN: Review of case reports and original research studies assessing the interference between SCS and CPM/ICD. MATERIALS AND METHODS: PubMed and Cochrane databases were searched for articles commenting on the interference between SCS and CPM/ICD. The search criteria which generated the greatest number of relevant studies was (spinal cord stimulator AND [pacemaker OR implantable cardioverter defibrillator]). Additional, empiric review was conducted using JSTOR, ScienceDirect, and EBSCOhost databases; however, no additional eligible studies were identified. Data were extracted, summarized into tables, and quantitatively analyzed using LibreTexts and MedCalc software. RESULTS: There was no statistically significant interference observed between SCS and CPM/ICD devices in patients regardless of indication for SCS placement and SCS lead polarity. LIMITATIONS: Limited by variability of patient cases and variability in maximum frequency and amplitude of SCS devices tried in individual cases. Also limited by small sample size and the absence of a standard definition for device interference across studies. CONCLUSIONS: Interference between cardiac devices and SCSs is a rare occurrence. As there are currently no published guidelines, devices should be interrogated on a case-by-case basis in the SCS trial period (if implanted after cardiac device), during permanent implantation, and during scheduled follow-up visits. Peri-operative testing should include increasing the SCS settings to maximally tolerated levels with cardiac device set at its maximum sensitivity.

Acute kidney injury after radial or femoral artery access in ST-segment elevation myocardial infarction: AKI-SAFARI.

BACKGROUND: Acute kidney injury (AKI) complicating primary percutaneous coronary intervention (PCI) is an independent predictor of short- and long-term outcomes in patients presenting with ST-elevation myocardial infarction (STEMI). Prior studies suggest a lower incidence of AKI in patients undergoing PCI through radial artery compared to femoral artery access; however, no randomized clinical trials have specifically investigated this question in patients presenting with STEMI. METHODS: To determine whether radial access (RA) is associated with a reduced frequency of AKI following primary PCI, we performed a substudy of the SAFARI-STEMI trial. The SAFARI-STEMI trial was an open-label, multicenter trial, which randomized patients presenting with STEMI to RA or femoral access (FA), between July 2011 and December 2018. The primary outcome of this post hoc analysis was the incidence of AKI, defined as an absolute (>0.5 mg/dL) or relative (>25%) increase in serum creatinine from baseline. RESULTS: In total 2,285 (99.3%) of the patients enrolled in SAFARI-STEMI were included in the analysis-1,132 RA and 1,153 FA. AKI occurred in 243 (21.5%) RA patients and 226 (19.6%) FA patients (RR: 0.91, 95% CI: 0.78-1.07, P = .27). An absolute increase in serum creatinine >0.5 mg/dL was seen in 49 (4.3%) radial and 52 (4.5%) femoral patients (RR: 1.04, 95% CI: 0.71-1.53, P = .83). AKI was lower in both groups when the KDIGO definition was applied (RA 11.9% vs FA 10.8%; RR: 0.90, 95% CI: 0.72-1.13, P = .38). CONCLUSIONS: Among STEMI patients enrolled in the SAFARI-STEMI trial, there was no association between catheterization access site and AKI, irrespective of the definition applied. These results challenge the independent association between catheterization access site and AKI noted in prior investigations.

Impact of baseline beta-blocker use on inotrope response and clinical outcomes in cardiogenic shock: a subgroup analysis of the DOREMI trial.

BACKGROUND: Cardiogenic shock (CS) is associated with significant morbidity and mortality. The impact of beta-blocker (BB) use on patients who develop CS remains unknown. We sought to evaluate the clinical outcomes and hemodynamic response profiles in patients treated with BB in the 24 h prior to the development of CS. METHODS: Patients with CS enrolled in the DObutamine compaREd to MIlrinone trial were analyzed. The primary outcome was a composite of all-cause mortality, resuscitated cardiac arrest, need for cardiac transplant or mechanical circulatory support, non-fatal myocardial infarction, transient ischemic attack or stroke, or initiation of renal replacement therapy. Secondary outcomes included the individual components of the primary composite and hemodynamic response profiles derived from pulmonary artery catheters. RESULTS: Among 192 participants, 93 patients (48%) had received BB therapy. The primary outcome occurred in 47 patients (51%) in the BB group and in 52 (53%) in the no BB group (RR 0.96; 95% CI 0.73-1.27; P = 0.78) throughout the in-hospital period. There were fewer early deaths in the BB group (RR 0.41; 95% CI 0.18-0.95; P = 0.03). There were no differences in other individual components of the primary outcome or in hemodynamic response between the two groups throughout the remainder of the hospitalization. CONCLUSIONS: BB therapy in the 24 h preceding the development of CS did not negatively influence clinical outcomes or hemodynamic parameters. On the contrary, BB use was associated with fewer deaths in the early resuscitation period, suggesting a paradoxically protective effect in patients with CS. Trial registration ClinicalTrials.gov Identifier: NCT03207165.

Effect of Moderate vs Mild Therapeutic Hypothermia on Mortality and Neurologic Outcomes in Comatose Survivors of Out-of-Hospital Cardiac Arrest: The CAPITAL CHILL Randomized Clinical Trial.

Importance: Comatose survivors of out-of-hospital cardiac arrest experience high rates of death and severe neurologic injury. Current guidelines recommend targeted temperature management at 32 °C to 36 °C for 24 hours. However, small studies suggest a potential benefit of targeting lower body temperatures. Objective: To determine whether moderate hypothermia (31 °C), compared with mild hypothermia (34 °C), improves clinical outcomes in comatose survivors of out-of-hospital cardiac arrest. Design, Setting, and Participants: Single-center, double-blind, randomized, clinical superiority trial carried out in a tertiary cardiac care center in eastern Ontario, Canada. A total of 389 patients with out-of-hospital cardiac arrest were enrolled between August 4, 2013, and March 20, 2020, with final follow-up on October 15, 2020. Interventions: Patients were randomly assigned to temperature management with a target body temperature of 31 °C (n = 193) or 34 °C (n = 196) for a period of 24 hours. Main Outcomes and Measures: The primary outcome was all-cause mortality or poor neurologic outcome at 180 days. Neurologic outcome was assessed using the Disability Rating Scale, with poor neurologic outcome defined as a score greater than 5 (range, 0-29, with 29 being the worst outcome [vegetative state]). There were 19 secondary outcomes, including mortality at 180 days and length of stay in the intensive care unit. Results: Among 367 patients included in the primary analysis (mean age, 61 years; 69 women [19%]), 366 (99.7%) completed the trial. The primary outcome occurred in 89 of 184 patients (48.4%) in the 31 °C group and in 83 of 183 patients (45.4%) in the 34 °C group (risk difference, 3.0% [95% CI, 7.2%-13.2%]; relative risk, 1.07 [95% CI, 0.86-1.33]; P = .56). Of the 19 secondary outcomes, 18 were not statistically significant. Mortality at 180 days was 43.5% and 41.0% in patients treated with a target temperature of 31 °C and 34 °C, respectively (P = .63). The median length of stay in the intensive care unit was longer in the 31 °C group (10 vs 7 days; P = .004). Among adverse events in the 31 °C group vs the 34 °C group, deep vein thrombosis occurred in 11.4% vs 10.9% and thrombus in the inferior vena cava occurred in 3.8% and 7.7%, respectively. Conclusions and Relevance: In comatose survivors of out-of-hospital cardiac arrest, a target temperature of 31 °C did not significantly reduce the rate of death or poor neurologic outcome at 180 days compared with a target temperature of 34 °C. However, the study may have been underpowered to detect a clinically important difference. Trial Registration: ClinicalTrials.gov Identifier: NCT02011568.

Overprescription of Opioids Following Outpatient Anorectal Surgery: A Single-Institution Study.

BACKGROUND: Surgeons contribute to the opioid epidemic by overprescribing opioids for postoperative pain. Excess, unused opioids may be diverted for misuse/abuse. OBJECTIVE: This study aimed to characterize opioid prescribing and use among patients undergoing outpatient anorectal procedures and to assess the adequacy of postoperative pain management. DESIGN: This is a retrospective cohort study, prospective cross-sectional survey. SETTINGS: Patients were treated by colorectal surgeons in an academic medical center between January 2018 and September 2019. PATIENTS: Six hundred twenty-seven patients undergoing an outpatient anorectal procedure were included. MAIN OUTCOME MEASURES: The primary outcomes measured were the opioids prescribed at discharge, opioid prescription refills, patient-reported outcomes regarding opioid use, and the adequacy of postoperative pain management in terms of pain intensity and pain interference. Opioids were standardized to 5-mg oxycodone pills. Patient-reported outcomes were assessed by using previously validated instruments. RESULTS: The majority of patients underwent fistula surgery (n = 234) followed by examination under anesthesia (n = 183), hemorrhoidectomy (n = 131), incision and drainage (n = 51), and pilonidal excision (n = 28). Most patients received opioids (78% fistula, 49% examination under anesthesia, 87% hemorrhoidectomy, 71% incision and drainage, 96% pilonidal). Patients undergoing examination under anesthesia received the fewest opioid pills (median 10; range 3-50) followed by patients undergoing fistula surgery (median13, range 1-50), incision and drainage (median 15, range 3-120), pilonidal excisions (median 15, range 3-60), and hemorrhoidectomies (median 28, range 3-60). Regardless of procedure, the majority of patients used fewer than 5 opioid pills postoperatively. Patients undergoing pilonidal excisions had the largest number of excess unused pills (median 14, range 0-30) followed by patients undergoing fistula surgery and incision and drainage (median 7, ranges 0-30 and 5-17), hemorrhoidectomy (median 6, range 0-50), and examination under anesthesia (median 2, range 0-23). Whereas patients undergoing hemorrhoidectomy reported higher pain levels following discharge, most reported minimal interference with day-to-day activities due to pain regardless of the procedure performed. LIMITATIONS: The limitations of this study included recall bias and sample bias. CONCLUSIONS: The majority of patients do not need more than five to ten 5-mg oxycodone equivalents to achieve adequate pain management after outpatient anorectal surgical procedures. See Video Abstract at http://links.lww.com/DCR/B347. EXCESO DE PRESCRIPCIÓN DE OPIOIDES DESPUÉS DE UNA CIRUGÍA ANORRECTAL AMBULATORIA: UN ESTUDIO DE UNA SOLA INSTITUCIÓN: Cirujanos contribuyen a la epidemia de opioides al recetar en exceso opioides para el dolor postoperatorio. El exceso de opioides no utilizados puede ser desviado por para mal uso o abuso.Caracterizar la prescripción y el uso de opioides entre pacientes sometidos a procedimientos anorrectales ambulatorios y evaluar la efectividad del tratamiento del dolor postoperatorio.Estudio de cohorte retrospectivo, encuesta transversal prospectiva.pacientes tratados por cirujanos colorrectales en un centro médico académico entre enero de 2018 y septiembre de 2019.se incluyeron 627 pacientes que se sometieron a un procedimiento anorrectal ambulatorio.Opioides recetados al alta, reabastecimientos de prescripción de opioides, resultados informados por el paciente con respecto al uso de opioides y efectividad del manejo del dolor postoperatorio en términos de intensidad del dolor y trastornos secundarios a dolor. Los opioides se estandarizaron con píldoras de oxicodona de 5 mg. Los resultados informados por los pacientes se evaluaron utilizando instrumentos previamente validados.La mayoría de los pacientes fueron sometidos a cirugía de fístula (n = 234) seguida de un examen bajo anestesia (EUA; n = 183), hemorroidectomía (n = 131), incisión y drenaje (I&D) (n = 51) y escisión pilonidal (n = 28). La mayoría de los pacientes recibieron opioides (78% fístula, 49% EUA, 87% hemorroidectomía, 71% I&D, 96% pilonidal). Las EUA recibieron la menor cantidad de píldoras opioides (mediana 10, rango 3-50) seguidas de fístula (mediana 13, rango 1-50), I y D (mediana 15, rango 3-120), pilonidales (mediana 15, rango 3-60) y hemorroides. (mediana 28, rango 3-60). Independientemente del procedimiento, la mayoría de los pacientes usaron menos de cinco píldoras opioides después de la operación. Los pacientes pilonidales tuvieron el mayor número de píldoras no utilizadas en exceso (mediana 14, rango 0-30) seguido de fístula e I&D (mediana 7, rangos 0-30 y 5-17, respectivamente), hemorroidectomía (mediana 6, rango 0-50) y EUA (mediana 2, rango 0-23). Si bien los pacientes con hemorroidectomía informaron niveles de dolor más altos después del alta, la mayoría de pacientes informaron un mínimo de interferencia con las actividades diarias debido al dolor, independientemente del procedimiento realizado.Sesgo de recuerdo autoinformado, sesgo de muestra.La mayoría de los pacientes no necesitan más de cinco a diez equivalentes de oxicodona de 5 mg para lograr un manejo adecuado del dolor después de procedimientos quirúrgicos anorrectales ambulatorios. Consulte Video Resumen en http://links.lww.com/DCR/B347. (Traducción-Dr. Adrian Ortega).

Coronary Artery Disease in patients with End-Stage Kidney Disease; Current perspective and gaps of knowledge.

Coronary artery disease (CAD) is very common in dialysis patients. One third have preexisting CAD and another one third have significant occult disease at the time of starting dialysis. Symptoms are often absent or are atypical, emphasizing the need for vigorous screening, specifically in patients awaiting transplant. The lesions tend to be heavily calcified, diffuse, and involve multiple vessels, consequently, percutaneous coronary interventions are more complicated to perform, and are less successful in achieving and maintaining short- and long-term patency. Dialysis patients have been excluded from the randomized controlled trials on which the current standards for managing CAD have been established. Due to differences in pathobiology and risks and benefits, it is uncertain that the results of these clinical trials extrapolate to patients with advanced chronic kidney disease (CKD). Here we review the data from observational studies and identify special considerations concerning the diagnosis and management of CAD in dialysis patients, including the use of noninvasive functional testing vs anatomical testing, the management of acute coronary syndromes and of stable coronary artery disease, the role for percutaneous revascularization vs coronary artery bypass grafting, and of platelet inhibitor therapy after coronary stenting. We review the preliminary results of the recently published ISCHEMIA-CKD trial, the only trial to date to involve large numbers of dialysis patients. This is the first of, hopefully, many trials in the pipeline that will examine therapies for CAD specifically in patients with advanced CKD, a growing population that is at particularly high risk for poor outcomes.

In-hospital outcomes of STEMI patients on warfarin undergoing primary PCI.

OBJECTIVES: We sought to describe the safety and efficacy outcomes of patients on warfarin presenting with ST-elevation myocardial infarction (STEMI). BACKGROUND: Limited data exist on the outcomes and optimal management of STEMI patients on warfarin undergoing primary percutaneous coronary intervention (PCI). METHODS: Baseline characteristics and outcomes were prospectively collected for 2,390 consecutive STEMI patients referred for primary PCI. Patients were stratified based on warfarin use at baseline. The primary safety endpoint was the rate of in-hospital bleeding (a composite of major bleeding or minor bleeding) according to the thrombolysis in myocardial infarction (TIMI) classification. Efficacy endpoints included major adverse cardiovascular events (MACE), defined as death, myocardial infarction, or stroke, as well as intracranial bleeding, cardiogenic shock, and length of stay. Multiple logistic regression was used to determine if warfarin was independently associated with bleeding and MACE. RESULTS: Warfarin patients (n = 59 vs. n = 2,331) were significantly older (73.2 years vs. 61.7 years; P < 0.01), and more likely to present as Killip Class IV (13.6% vs. 2.7%; P < 0.01). TIMI major/minor bleeding occurred in 30.4% of the warfarin patients and 14.2% of the control patients (P < 0.01). After adjustment warfarin was independently associated with an increased risk of bleeding (OR 2.08; P = 0.04). Warfarin patients also had an increased frequency of MACE (20.3% vs. 5.9%; P < 0.01), though this was not significant after adjustment (OR 2.00; P = 0.10). CONCLUSIONS: STEMI patients on warfarin referred for primary PCI are more likely to experience bleeding. New strategies are needed to optimize the management and minimize bleeding in this high-risk population.

Clinical performance of Rb-82 myocardial perfusion PET and Tc-99m-based SPECT in patients with extreme obesity.

BACKGROUND: We evaluated the performance of stress imaging with technetium-99m-labeled tetrofosmin single-photon emission computed tomography (SPECT) and rubidium-82 positron emission tomography (PET) in patients with extreme obesity, defined as body mass index ≥40 kg/m2. METHODS: We identified patients with extreme obesity who underwent angiography in our center and either stress SPECT or PET within the previous six months. Cohorts of patients with extreme obesity and a <5% pretest likelihood of CAD who underwent SPECT (N = 25) or PET (N = 25) were also included. RESULTS: In total, 108 patients who underwent SPECT (N = 57) or PET (N = 51) were identified. Scan interpretation was classified as definitely normal or abnormal in 83.3% of PET and 60.5% of SPECT scans, respectively (P < .01). PET demonstrated higher diagnostic accuracy and normalcy rate. PET was found to have higher specificity for the pooled cohort. Similar findings were observed using stenosis cut-offs of ≥50% and ≥70%. CONCLUSIONS: In patients with extreme obesity, PET enabled more definitive scan interpretation with less artifact compared to SPECT. PET provided higher diagnostic accuracy and specificity in the detection of obstructive coronary artery disease.

DNA Area and NETosis Analysis (DANA): a High-Throughput Method to Quantify Neutrophil Extracellular Traps in Fluorescent Microscope Images.

BACKGROUND: Neutrophil extracellular traps (NETs), extracellular structures composed of decondensed chromatin and antimicrobial molecules, are released in a process called NETosis. NETs, which are part of normal host defense, have also been implicated in multiple human diseases. Unfortunately, methods for quantifying NETs have limitations which constrain the study of NETs in disease. Establishing optimal methods for NET quantification holds the potential to further elucidate the role of NETs in normal and pathologic processes. RESULTS: To better quantify NETs and NET-like structures, we created DNA Area and NETosis Analysis (DANA), a novel ImageJ/Java based program which provides a simple, semi-automated approach to quantify NET-like structures and DNA area. DANA can analyze many fluorescent microscope images at once and provides data on a per cell, per image, and per sample basis. Using fluorescent microscope images of Sytox-stained human neutrophils, DANA quantified a similar frequency of NET-like structures to the frequency determined by two different individuals counting by eye, and in a fraction of the time. As expected, DANA also detected increased DNA area and frequency of NET-like structures in neutrophils from subjects with rheumatoid arthritis as compared to control subjects. Using images of DAPI-stained murine neutrophils, DANA (installed by an individual with no programming background) gave similar frequencies of NET-like structures as the frequency of NETs determined by two individuals counting by eye. Further, DANA quantified more NETs in stimulated murine neutrophils compared to unstimulated, as expected. CONCLUSIONS: DANA provides a means to quantify DNA decondensation and the frequency of NET-like structures using a variety of different fluorescent markers in a rapid, reliable, simple, high-throughput, and cost-effective manner making it optimal to assess NETosis in a variety of conditions.

Incidence, predictors, and clinical outcomes of early stent thrombosis in acute myocardial infarction patients treated with primary percutaneous coronary angioplasty (insights from the University of Ottawa Heart Institute STEMI registry).

BACKGROUND: Early stent thrombosis (ST) remains an important complication of primary percutaneous intervention (PCI). To date, our information on angiographic and clinical predictors of early ST in ST-segment elevation myocardial infarction (STEMI) patients treated with primary PCI is limited. METHODS: We tried to evaluate the incidence, predictors, and outcomes of early ST in real-world patients treated with primary PCI. We identified all the patients presenting with STEMI between June 2004 and January 2011 who underwent primary PCI as the primary mode of revascularization. Diagnosis of ST was made as per the standard definition proposed by the Academic Research Consortium. RESULTS: The incidence of early ST was 1% among 2,303 patients treated with primary PCI. Definite and probable early ST occurred in 22 and 2 patients, respectively. Patients with early ST had higher in-hospital (P = 0.03) and 30-day mortality (P = 0.048). The rate of cardiogenic shock (P = 0.0006) and cerebrovascular accident (P = 0.0004) was also greater in the early ST group. Smaller stent diameter and lower use of intracoronary glycoprotein IIb/IIIa inhibitor were associated with higher rate of early ST. There was a trend of higher bivalirudin use in ST group, which did not reach significance (P = 0.07) On IVUS imaging, stent malapposition and uncovered plaque area were noted in 6 out of 11 cases. CONCLUSION: The incidence of early ST in primary PCI cohort is low. However, it is still associated with higher mortality and morbidity. Small stent diameter and disuse of intracoronary glycoprotein IIb/IIIa inhibitor may be associated with early ST.

Transcatheter Aortic Valve Implantation (TAVI) for Native Aortic Valve Regurgitation　- A Systematic Review.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) has become the standard of care for management of high-risk patients with aortic stenosis. Limited data is available regarding the performance of TAVI in patients with native aortic valve regurgitation (NAVR).Methods and Results:We performed a systematic review from 2002 to 2016. The primary outcome was device success as per VARC-2 criteria. Secondary endpoints included procedural complications, and 30-day and 1-year mortality rates. A total of 175 patients were included from 31 studies. Device success was reported in 86.3% of patients - with device failure driven by moderate aortic regurgitation (AR ≥3+) and/or need for a second device. Procedural complications were rare, with no procedural deaths, myocardial infarctions or annular ruptures reported. Procedural safety was acceptable with a low 30-day incidence of stroke (1.5%). The 30-day and 1-year overall mortality rates were 9.6% and 20.0% (cardiovascular death, 3.8% and 10.1%, respectively). Patients receiving 2nd-generation valves demonstrated similar safety profiles with greater device success compared with 1st-generation valves (96.2% vs. 78.4%). This was driven by the higher incidence of second-valve implantation (23.4% vs. 1.7%) and significant paravalvular leak (8.3% vs. 0.0%). CONCLUSIONS: TAVI demonstrates acceptable safety and efficacy in high-risk patients with severe NAVR. Second-generation valves may afford a similar safety profile with improved device success. Dedicated studies are needed to definitively establish the efficacy of TAVI in this population.

Transcatheter Aortic Valve Implantation in Intermediate Surgical Risk Patients With Severe Aortic Stenosis: A Systematic Review and Meta-Analysis.

BACKGROUND: Recent data from randomised and observational studies have reported non-inferior outcomes for transcatheter aortic valve implantation (TAVI) compared to surgical aortic valve replacement (SAVR) in intermediate-risk patients. We performed a systematic review to evaluate the mortality of TAVI compared to SAVR in intermediate-risk patients. METHODS: A comprehensive search of four major databases (Embase, Ovid MEDLINE, PubMed, and Google Scholar) was performed from their inception to 29 April 2016. We included original research studies reporting data on TAVI and SAVR in intermediate-risk patients. We compared the outcomes of TAVI to SAVR. RESULTS: A total of 2,375 and 2,377 intermediate-risk patients underwent TAVI and SAVR respectively. The 30-day all-cause (p=0.07), 30-day cardiac (p=0.53), and 12-month all-cause mortality (p=0.34) was similar between the two groups. However, TAVI through transfemoral access had a significantly lower mortality than SAVR (OR 0.58, p=0.006). The incidence of ≥moderate aortic incompetence (p<0.00001) and pacemaker implantation (p<0.0001) was higher in the TAVI group. CONCLUSIONS: In the intermediate-risk patients, the 30-day and 12-month mortality are similar between TAVI and SAVR. Increased operator experience and improved device technology have led to a significant reduction in mortality in intermediate-risk patients undergoing TAVI.

Evaluation of Cobalt and Chromium Levels Following Implantation of Cobalt Chromium Coronary Stents: A Pilot Study.

BACKGROUND: Large increases in myocardial trace elements may adversely affect metabolism and become detrimental to cardiac function. Percutaneous coronary intervention (PCI) allows for the revascularisation of obstructive coronary artery disease using drug-eluting stents. These stents are comprised of a metallic stent backbone covered in an engineered polymer which delivers a drug over a prescribed period to the vessel wall. Given the potential implications of trace metal accumulation within the myocardium, our goal is to determine if metallic coronary stents are able to cause detectable elevations in serum cobalt and/or chromium levels. METHODS: This study was a single centre, observational, pilot study with 20 patients who underwent planned PCI with implantation of a cobalt chromium drug eluting stent. Serum blood samples were drawn at baseline prior to PCI, 4hours post-stent deployment and at the time of routine follow-up after PCI. All blood samples were analysed for cobalt and chromium concentrations. The primary outcome of this study was the difference in serum cobalt and chromium levels at routine clinical follow-up. RESULTS: The mean follow up was 64.1±17.3 days. There was no difference in serum cobalt levels when comparing baseline and routine clinical follow up (3.32±2.14nmol/L vs. 3.14±1.00nmol/L, p=0.99) nor in chromium levels (4.24±2.31nmol/L vs. 2.82±1.22 nmol/L, p=0.11). There was also no difference between baseline and 4hours post-PCI serum concentrations. CONCLUSIONS: Percutaneous coronary intervention with cobalt chromium coronary stents does not appear to cause an elevation in these trace element serum concentrations.

Efficacy and Complications of Transcatheter Aortic Valve Implantation With and Without Balloon Aortic Valvuloplasty.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is an effective treatment for severe aortic stenosis in high-risk patients. Several complications related to the TAVI procedure, including aortic regurgitation (AR), cerebrovascular accident (CVA) and the requirement for permanent pacemaker (PPM), are thought to be secondary to balloon aortic valvuloplasty (BAV) before TAVI. The aim of the present review was to evaluate any beneficial role of the direct TAVI approach over BAVTAVI. METHODS: A comprehensive search of major databases was performed. Only studies comparing TAVI with and without BAV were included. A total of nine full length articles was included in the analysis. RESULTS: Among 2,650 patients, 1,043 underwent 'direct TAVI' without pre-BAV, while 1,607 underwent TAVI following BAV. Overall, there was no difference between the 30-day all-cause mortality (OR 0.96, 95% CI 0.63-1.47, p = 0.86), CVA (OR 0.81, 95% CI 0.34-1.92, p = 0.63) and PPM implantation (OR 0.84, 95% CI 0.66- 1.05, p = 0.12) between the two approaches. The rate of moderate to severe AR was significantly lower with direct TAVI implantation (OR 0.44, 95% CI 0.20-0.96, p = 0.04). In the case of self-expandable valves, direct TAVI was associated with a lower device success (OR 5.15, 95% CI 1.33-19.9, p = 0.02). CONCLUSIONS: No difference was identified in mortality between direct TAVI and BAV-TAVI. However, direct TAVI is associated with a lower incidence of AR, a finding that would only be confirmed by conducting further randomized studies.

Predicting Acute Kidney Injury following Transcatheter Aortic Valve Replacement.

PURPOSE: Acute kidney injury occurs in up to a quarter of patients following transcatheter aortic valve replacement (TAVR) and has been associated with increased short and long-term mortality rates. A variety of patient characteristics predictive of post-TAVR acute kidney injury (AKI) have been identified, however discrepancies among studies exist almost uniformly. We investigated the hypothesis that the change in glomerular filtration rate (ΔGFR) in response to contrast administered during pre-TAVR coronary angiography is predictive of ΔGFR post-TAVR. METHODS: The study comprised 195 patients who underwent TAVR at a single center between August 2008 and June 2015 and were prospectively included in the CAPITAL TAVR registry. Multiple linear regression analysis was conducted to estimate the effect of independent variables on the change in renal function post-TAVR. RESULTS: There was no relationship identified between the ΔGFR post-angiogram and the ΔGFR post-TAVR (r=0.043, P=0.582). Multiple linear regression analysis revealed that a significant amount of the change in renal function post-TAVR can be explained by the patient's baseline creatinine (beta coefficient, -0.310, P.

A meta analysis of current status of alcohol septal ablation and surgical myectomy for obstructive hypertrophic cardiomyopathy.

OBJECTIVE: Our objective was to perform an updated systematic review to compare the efficacy and short- and long-term mortality of surgical myectomy (SM) and alcohol septal ablation (ASA) by including most recent and largest cohort studies published in last few years. BACKGROUND: SM and ASA are the two invasive strategies used to relieve left ventricular outflow tract obstruction (LVOTO) in patients with drug refractory symptomatic hypertrophic cardiomyopathy (HCM). In the absence of a randomized trial, we tried to compare the pros and cons of the two procedures using a systematic review and meta-analysis. METHOD: A comprehensive search of three major databases was performed. We included original research studies comparing data on ASA and SM. Of 1,143 citations, 10 studies were included in the analysis. RESULTS: A total of 805 patients underwent ASA and 1,019 underwent SM. Patients undergoing SM were younger (MD 6.3, P = 0.0001) and had higher reduction in the LVOT gradient (MD -9.56, P = 0.05). However, there was similar resolution of class III and IV symptoms between the two groups (P = 0.56). There was no difference in sudden cardiac death (SCD) (P = 0.93), short-term (P = 0.36), long-term all cause (P = 0.27), and long-term cardiac mortality (P = 0.58). Patients undergoing ASA had higher incidence of post procedure device implantation (OR 3.09, P < 0.00001). CONCLUSION: No significant difference in symptom relief was noted between the two approaches. ASA was as safe a myectomy with regards to SCD, short-term, and long-term mortality. © 2015 Wiley Periodicals, Inc.

Left Ventricular Outflow Tract Obstruction and Systolic Anterior Motion of the Mitral Valve in the Absence of Hypertrophic Cardiomyopathy.

Systolic anterior motion of the mitral valve is a mechanism for the development of left ventricular outflow tract (LVOT) obstruction. While often associated with left ventricular hypertrophy (LVH), a case is reported of symptomatic LVOT obstruction due to intrinsic mitral valve pathology in the absence of hypertrophy or cardiomyopathy. This case highlights the importance of recognizing isolated mitral valve pathology as a treatable cause of LVOT obstruction.

Granulocyte colony-stimulating factor therapy for stem cell mobilization following anterior wall myocardial infarction: the CAPITAL STEM MI randomized trial.

BACKGROUND: Small studies have yielded divergent results for administration of granulocyte colony-stimulating factor (G-CSF) after acute myocardial infarction. Adequately powered studies involving patients with at least moderate left ventricular dysfunction are lacking. METHODS: Patients with left ventricular ejection fraction less than 45% after anterior-wall myocardial infarction were treated with G-CSF (10 µg/kg daily for 4 days) or placebo. After initial randomization of 86 patients, 41 in the placebo group and 39 in the G-CSF group completed 6-month follow-up and underwent measurement of left ventricular ejection fraction by radionuclide angiography. RESULTS: Baseline and 6-week mean ejection fraction was similar for the G-CSF and placebo groups: 34.8% (95% confidence interval [CI] 32.6%-37.0%) v. 36.4% (95% CI 33.5%-39.2%) at baseline and 39.8% (95% CI 36.2%-43.4%) v. 43.1% (95% CI 39.2%-47.0%) at 6 weeks. However, G-CSF therapy was associated with a lower ejection fraction at 6 months relative to placebo (40.8% [95% CI 37.4%-44.2%] v. 46.0% [95% CI 42.7%-44.3%]). Both groups had improved left ventricular function, but change in left ventricular ejection fraction was lower in patients treated with G-CSF than in those who received placebo (5.7 [95% CI 3.4-8.1] percentage points v. 9.2 [95% CI 6.3-12.1] percentage points). One or more of a composite of several major adverse cardiac events occurred in 8 patients (19%) within each group, with similar rates of target-vessel revascularization. INTERPRETATION: In patients with moderate left ventricular dysfunction following anterior-wall infarction, G-CSF therapy was associated with a lower 6-month left ventricular ejection fraction but no increased risk of major adverse cardiac events. Future studies of G-CSF in patients with left ventricular dysfunction should be monitored closely for safety. TRIAL REGISTRATION: ClinicalTrials.gov, no. NCT00394498.

Off-Hours Presentation, Door-to-Balloon Time, and Clinical Outcomes in Patients Referred for Primary Percutaneous Coronary Intervention.

OBJECTIVES: Presentation with ST-segment-elevation myocardial infarction (STEMI) during off-hours may impact timely reperfusion and clinical outcomes. We investigated the association between off-hours presentation, door-to-balloon time, and in-hospital mortality in patients with STEMI referred for primary percutaneous coronary intervention (PCI). METHODS: We included consecutive patients referred for primary PCI at the University of Ottawa Heart Institute between July 2004 and December 2017. The off-hours group included patients presenting on weekends, statutory holidays, or between 18:00 to 07:59 hours on weekdays. The on-hours group included patients presenting between 08:00 and 17:59 hours on weekdays. The primary clinical outcome was the adjusted in-hospital mortality. The primary quality-of-care indicator was door-to-balloon time. RESULTS: A total of 5132 patients were included, with 3152 (61.4%) in the off-hours group and 1980 (38.6%) in the on-hours group. The median door-to-balloon time was longer in the off-hours group compared with the on-hours group (102 minutes vs 77 minutes; P<.001), while the median onset-to-door time was similar (P=.40). There was no difference in the rates of in-hospital mortality (3.5% vs 3.0%; P=.32) or in the adjusted mortality (odds ratio, 1.2; 95% confidence interval, 0.8-1.8; P=.44) between off-hours and on-hours groups. However, door-to-balloon time was an independent predictor of in-hospital mortality (P<.01) and off-hours presentation was an independent predictor of longer door-to-balloon time (P<.001), with an excess of 22.1 minutes. CONCLUSION: Patients treated with primary PCI during off-hours had longer door-to-balloon times. Treatment during off-hours was an independent predictor of longer door-to-balloon time and longer door-to-balloon times were associated with higher mortality.

X-ray-induced photo-chemistry and X-ray absorption spectroscopy of biological samples.

As synchrotron light sources and optics deliver greater photon flux on samples, X-ray-induced photo-chemistry is increasingly encountered in X-ray absorption spectroscopy (XAS) experiments. The resulting problems are particularly pronounced for biological XAS experiments. This is because biological samples are very often quite dilute and therefore require signal averaging to achieve adequate signal-to-noise ratios, with correspondingly greater exposures to the X-ray beam. This paper reviews the origins of photo-reduction and photo-oxidation, the impact that they can have on active site structure, and the methods that can be used to provide relief from X-ray-induced photo-chemical artifacts.