Objectives This study sought to characterize major bleeding on the basis of the components of the major bleeding definition, to explore major bleeding by location, to define 30-day mortality after a ...major bleeding event, and to identify factors associated with major bleeding. Background Apixaban was shown to reduce the risk of major hemorrhage among patients with atrial fibrillation in the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) trial. Methods All patients who received at least 1 dose of a study drug were included. Major bleeding was defined according to the criteria of the International Society on Thrombosis and Haemostasis. Factors associated with major hemorrhage were identified using a multivariable Cox model. Results The on-treatment safety population included 18,140 patients. The rate of major hemorrhage among patients in the apixaban group was 2.13% per year compared with 3.09% per year in the warfarin group (hazard ratio HR 0.69, 95% confidence interval CI: 0.60 to 0.80; p < 0.001). Compared with warfarin, major extracranial hemorrhage associated with apixaban led to reduced hospitalization, medical or surgical intervention, transfusion, or change in antithrombotic therapy. Major hemorrhage followed by mortality within 30 days occurred half as often in apixaban-treated patients than in those receiving warfarin (HR 0.50, 95% CI: 0.33 to 0.74; p < 0.001). Older age, prior hemorrhage, prior stroke or transient ischemic attack, diabetes, lower creatinine clearance, decreased hematocrit, aspirin therapy, and nonsteroidal anti-inflammatory drugs were independently associated with an increased risk. Conclusions Apixaban, compared with warfarin, was associated with fewer intracranial hemorrhages, less adverse consequences following extracranial hemorrhage, and a 50% reduction in fatal consequences at 30 days in cases of major hemorrhage.
Background Stroke is a major cause of morbidity and mortality during open-heart surgery. Up to 60% of intraoperative cerebral events are emboli induced. This randomized, controlled, multicenter trial ...is the first human study evaluating the safety and efficacy of a novel aortic cannula producing simultaneous forward flow and backward suction for extracting solid and gaseous emboli from the ascending aorta and aortic arch upon their intraoperative release. Methods Sixty-six patients (25 females; 68 ± 10 years) undergoing elective aortic valve replacement surgery, with or without coronary artery bypass graft surgery, were randomized to the use of the CardioGard (CardioGard Medical, Or-Yehuda, Israel) Emboli Protection cannula (“treatment”) or a standard (“control”) aortic cannula. The primary endpoint was the volume of new brain lesions measured by diffusion-weighted magnetic resonance imaging (DW-MRI), performed preoperatively and postoperatively. Device safety was investigated by comparisons of complications rate, namely neurologic events, stroke, renal insufficiency and death. Results Of 66 patients (34 in the treatment group), 51 completed the presurgery and postsurgery MRI (27 in the treatment group). The volume of new brain lesion for the treatment group was (mean ± standard error of the mean) 44.00 ± 64.00 versus 126.56 ± 28.74 mm3 in the control group ( p = 0.004). Of the treatment group, 41% demonstrated new postoperative lesions versus 66% in the control group ( p = 0.03). The complication rate was comparable in both groups. Conclusions The CardioGard cannula is safe and efficient in use during open-heart surgery. Efficacy was demonstrated by the removal of a substantial amount of emboli, a significant reduction in the volume of new brain lesions, and the percentage of patients experiencing new brain lesions.
Objective “Chimney” techniques used to extend landing zones for endovascular aortic repair (chEVAR) have been increasingly reported; however, concerns about durability and patency remain. The purpose ...of this analysis was to examine midterm outcomes of chEVAR. Methods All patients at the University of Florida treated with chEVAR were reviewed. Major adverse events (MAEs) were recorded and defined as any chimney stent thrombosis, type Ia endoleak in follow-up, reintervention, 30-day/in-hospital death, or ≥25% decrease in estimated glomerular filtration rate after discharge. Primary end points included chimney stent patency and freedom from MAE. Secondary end points included complications and long-term survival. Results From 2008 to 2012, 41 patients (age ± standard deviation, 73 ± 8 years; male, 66% n = 27) were treated with a total of 76 chimney stents (renal, n = 51; superior mesenteric artery, n = 16; celiac artery, n = 9) for a variety of indications: juxtarenal, 42% (n = 17, one rupture), suprarenal, 17% (n = 7), and thoracoabdominal aneurysm, 17% (n = 7); aortic anastomotic pseudoaneurysm, 15% (n = 6; three ruptures); type Ia endoleak after EVAR, 7% (n = 3); and atheromatous disease, 2% (n = 1). Two patients had a single target vessel abandoned because of cannulation failure, and one had a type Ia endoleak at case completion (technical success, 93%). Intraoperative complications occurred in seven patients (17%), including graft maldeployment with unplanned mesenteric chimney (n = 2) and access vessel injury requiring repair (n = 5). Major postoperative complications developed in 20% (n = 8). The 30-day mortality and in-hospital mortality were 5% (n = 2) and 7% (n = 3), respectively. At median follow-up of 18.2 months (range, 1.4-41.5 months), 28 of 33 patients (85%) with available postoperative imaging experienced stabilization or reduction of abdominal aortic aneurysm sac diameters. Nine patients (32%) developed endoleak at some point during follow-up (type Ia, 7% n = 3; type II, 10% n = 4; indeterminate, 7% n = 3), and one patient underwent open, surgical conversion. The estimated probability of freedom from reintervention (±standard error mean) was 96% ± 4% at both 1 year and 3 years. Primary patency of all chimney stents was 88% ± 5% and 85% ± 5% at 1 year and 3 years, respectively. Corresponding freedom from MAEs was 83% ± 7% and 57% ± 10% at 1 year and 3 years. The actuarial estimated survival for all patients at 1 year and 5 years was 85% ± 6% and 65% ± 8%, respectively. Conclusions These results demonstrate that chEVAR can be completed with a high degree of success; however, perioperative complications and MAEs during follow-up, including loss of chimney patency and endoleak, may occur at a higher rate than previously reported. Elective use of chEVAR should be performed with caution, and comparison to open and fenestrated EVAR is needed to determine long-term efficacy of this technique.
Background A large proportion of newly created arteriovenous fistulas cannot be used for dialysis because they fail to mature adequately to support the hemodialysis blood circuit. The Hemodialysis ...Fistula Maturation (HFM) Study was designed to elucidate clinical and biological factors associated with fistula maturation outcomes. Study Design Multicenter prospective cohort study. Setting & Participants Approximately 600 patients undergoing creation of a new hemodialysis fistula will be enrolled at 7 centers in the United States and followed up for as long as 4 years. Predictors Clinical, anatomical, biological, and process-of-care attributes identified pre-, intra-, or postoperatively. Outcomes The primary outcome is unassisted clinical maturation, defined as successful use of the fistula for dialysis for 4 weeks without maturation-enhancing procedures. Secondary outcomes include assisted clinical maturation, ultrasound-based anatomical maturation, fistula procedures, fistula abandonment, and central venous catheter use. Measurements Preoperative ultrasound arterial and venous mapping, flow-mediated and nitroglycerin-mediated brachial artery dilation, arterial pulse wave velocity, and venous distensibility; intraoperative vein tissue collection for histopathologic and molecular analyses; postoperative ultrasounds at 1 day, 2 weeks, 6 weeks, and prior to fistula intervention and initial cannulation. Results Assuming complete data, no covariate adjustment, and unassisted clinical maturation of 50%, there will be 80% power to detect ORs of 1.83 and 1.61 for dichotomous predictor variables with exposure prevalences of 20% and 50%, respectively. Limitations Exclusion of 2-stage transposition fistulas limits generalizability. The requirement for study visits may result in a cohort that is healthier than the overall population of patients undergoing fistula creation. Conclusions The HFM Study will be of sufficient size and scope to: (1) evaluate a broad range of mechanistic hypotheses, (2) identify clinical practices associated with maturation outcomes, (3) assess the predictive utility of early indicators of fistula outcome, and (4) establish targets for novel therapeutic interventions to improve fistula maturation.
Objective Access-related hand ischemia (ARHI) is a major complication after hemodialysis access construction. This study was designed to prospectively describe its incidence, predictors, ...interventions, and associated access maturation. Methods The Hemodialysis Fistula Maturation Study is a multicenter prospective cohort study designed to identify predictors of autogenous arteriovenous access (arteriovenous fistula AVF) maturation. Symptoms and interventions for ARHI were documented, and participants who received interventions for ARHI were compared with other participants using a nested case-control design. Associations of ARHI with clinical, ultrasound, vascular function, and vein histologic variables were each individually evaluated using conditional logistic regression; the association with maturation was assessed by relative risk, Pearson χ2 test, and multiple logistic regression. Results The study cohort included 602 participants with median follow-up of 2.1 years (10th-90th percentiles, 0.7-3.5 years). Mean age was 55.1 ± 13.4 (standard deviation) years; the majority were male (70%), white (47%), diabetic (59%), smokers (55%), and on dialysis (64%) and underwent an upper arm AVF (76%). Symptoms of ARHI occurred in 45 (7%) participants, and intervention was required in 26 (4%). Interventions included distal revascularization with interval ligation (13), ligation (7), banding (4), revision using distal inflow (1), and proximalization of arterial inflow (1). Interventions were performed ≤7 days after AVF creation in 4 participants (15%), between 8 and 30 days in 6 (23%), and >30 days in 16 (63%). Female gender (odds ratio, 3.17; 95% confidence interval, 1.27-7.91; P = .013), diabetes (13.62 1.81-102.4; P = .011), coronary artery disease (2.60 1.03-6.58; P = .044), higher preoperative venous capacitance (per %/10 mm Hg, 2.76 1.07-6.52; P = .021), and maximum venous outflow slope (per mL/100 mL/min/10 mm Hg, 1.13 1.03-1.25; P = .011) were significantly associated with interventions; a lower carotid-femoral pulse wave velocity and the outflow vein diameter in the early postoperative period (days 0-3) approached significance ( P < .10). Intervention for ARHI was not associated with AVF maturation failure (unadjusted risk ratio, 1.18 0.69-2.04, P = .56; adjusted odds ratio, 0.97 0.41-2.31, P = .95). Conclusions Remedial intervention for ARHI after AVF construction is uncommon. Diabetes, female gender, capacitant outflow veins, and coronary artery disease are all associated with an increased risk of intervention. These higher risk patients should be counseled preoperatively, their operative plans should be designed to reduce the risk of hand ischemia, and they should be observed closely.
Contemporary pacemakers (PMs) are powered by primary batteries with a limited energy-storing capacity. PM replacements because of battery depletion are common and unpleasant and bear the risk of ...complications. Batteryless PMs that harvest energy inside the body may overcome these limitations.
The goal of this study was to develop a batteryless PM powered by a solar module that converts transcutaneous light into electrical energy.
Ex vivo measurements were performed with solar modules placed under pig skin flaps exposed to different irradiation scenarios (direct sunlight, shade outdoors, and indoors). Subsequently, 2 sunlight-powered PMs featuring a 4.6-cm2 solar module were implanted in vivo in a pig. One prototype, equipped with an energy buffer, was run in darkness for several weeks to simulate a worst-case scenario.
Ex vivo, median output power of the solar module was 1963 μW/cm2 (interquartile range IQR 1940–2107 μW/cm2) under direct sunlight exposure outdoors, 206 μW/cm2 (IQR 194–233 μW/cm2) in shade outdoors, and 4 μW/cm2 (IQR 3.6–4.3 μW/cm2) indoors (current PMs use approximately 10–20 μW). Median skin flap thickness was 4.8 mm. In vivo, prolonged SOO pacing was performed even with short irradiation periods. Our PM was able to pace continuously at a rate of 125 bpm (3.7 V at 0.6 ms) for 1½ months in darkness.
Tomorrow’s PMs might be batteryless and powered by sunlight. Because of the good skin penetrance of infrared light, a significant amount of energy can be harvested by a subcutaneous solar module even indoors. The use of an energy buffer allows periods of darkness to be overcome.
Transcatheter aortic valve implantation (TAVI) has become the standard therapy for high-risk and non-operable patients with severe aortic stenosis. However, the procedure involves several adverse ...effects, such as rhythm and conduction disturbances. Patients with postprocedural left bundle branch block may have an increased mortality risk, whereas patients with preprocedural right bundle branch block display a higher rate of postinterventional bradyarrhythmias.
The purpose of this study was to investigate the occurrence of high-degree atrioventricular block (AVB) in patients with preexisting bundle branch block (BBB) or BBB occurring during TAVI.
In this prospective single-center study, 50 consecutive patients undergoing TAVI with the Medtronic CoreValve Revalving System were included. Of these patients, 17 with preexisting BBB or BBB occurring during TAVI received a primary prophylactic permanent DDD pacemaker, programmed to the SafeR-mode and featuring dual-channel event counters as well as stored intracardiac electrograms. Pacemaker readouts and intracardiac electrograms were analyzed for the occurrence of high-degree AVB.
Ten of 17 patients (58.8%) with preexisting BBB or BBB occurring during TAVI developed episodes of high-degree AVB that were immediately terminated due to switch into DDD backup pacing. In 5 of the cases (29.4%), the first documented episode of high-degree AVB occurred after hospital discharge. Mean follow-up period was 578.1 ± 294.9 days.
Development of high-degree AVB is a common complication in patients with preexisting BBB or BBB occurring during TAVI. Accordingly, intensified monitoring might be reasonable, especially in patients treated with the self-expandable Medtronic CoreValve Revalving System.
Objective Open conversion after endovascular aortic aneurysm repair (EVAR-c) is performed nonelectively in up to 60% of cases. EVAR-c has been reported to have significantly greater risk of ...postoperative morbidity and mortality than primary aortic repair, but few data exist on outcomes for symptomatic or ruptured presentations. This study determined outcomes and identified predictors of postoperative major adverse cardiac events (MACEs) and mortality for patients undergoing nonelective EVAR-c compared with nonelective primary aortic repair (PAR) in the Vascular Quality Initiative (VQI). Methods All VQI patients undergoing urgent/emergency EVAR-c or urgent/emergency PAR from 2002 to 2014 were reviewed. Urgent presentation was defined by repair ≤24 hours of a nonelective admission, and emergency operations had clinical or radiographic evidence, or both, of rupture. End points included in-hospital MACE (myocardial infarction, dysrhythmia, congestive heart failure) and 30-day mortality. Possible covariates identified on univariate analysis ( P < .2) were entered into a multivariable model, and stepwise elimination identified the best subset of predictors. Generalized estimating equations logistic regression analysis was used to determine the relative effect of EVAR-c compared with PAR on outcomes. Results During the study interval, we identified 277 EVAR-c, and 118 (43%) underwent urgent/emergency repair. nonelective PAR was performed in 1388 of 6152 total (23%). EVAR-c patients were older (75 ± 9 vs 71 ± 10 years; P < .0001), more likely to be male (84% vs 74%; P = .02), and had a higher prevalence of hypertension (88% vs 79%; P = .02) and coronary artery disease (38% vs 27%; P = .01). No differences in MACE (EVAR-c, 31% n = 34 vs PAR, 30% n = 398) or any major postoperative complication (EVAR-c, 57% n = 63 vs PAR, 55% n = 740; P = .8) were found; however, 30-day mortality was significantly greater in EVAR-c (37% n = 41) than in (PAR, 24% n = 291; P = .003), with an odds ratio (OR) of 2.2 (95% confidence interval CI, 1.04-4.77; P = .04) for EVAR-c. Predictors of any MACE included age (OR, × 1.03 for each additional year; 95% CI, 1.01-1.03; P = .0002), male gender (OR, 1.3; 95% CI, 1.03-1.67; P = .03), body mass index ≤20 kg/m2 (OR, 1.8; 95% CI, 1.13-2.87; P = .01), chronic obstructive pulmonary disease (OR, 1.2; 95% CI, 0.86-1.80; P = .25), congestive heart failure (OR, 1.5; 95% CI, 0.98-2.34; P = .06), preoperative chronic β-blocker use (OR, 1.3; 95% CI, 0.97-1.63; P = .09), and emergency presentation (OR, 2.3; 95% CI, 1.8-3.01; area under the curve, 0.70; P < .0001). Significant predictors for 30-day mortality were age (OR × 1.07 for each additional year; 95% CI, 1.05-1.09; P < .0001), female gender (OR, 1.6; 95% CI, 1.01-2.46; P = .04), preoperative creatinine >1.8 mg/dL (OR, 1.6; 95% CI, 1.04-2.35; P = .03), an emergency presentation (OR, 4.8; 95% CI, 2.93-7.93; P < .0001), and renal/visceral ischemia (OR, × 1.1 for each unit increase log (time-minutes); 95% CI, 1.02-1.22; area under the curve, 0.84; P = .01). Conclusions Nonelective EVAR-c patients are older and have higher prevalence of cardiovascular risk factors than PAR patients. Similar rates of postoperative complications occur; however, urgent/emergency EVAR-c has a significantly higher risk of 30-day mortality than nonelective PAR. Several variables are identified that predict outcomes after these repairs and may help risk stratify patients to further inform clinical decision making when patients present nonelectively with EVAR failure.
Objective Spinal cord ischemia (SCI) is a devastating but potentially preventable complication of thoracic endovascular aortic repair (TEVAR). The purpose of this analysis was to determine what ...factors predict SCI after TEVAR. Methods All TEVAR procedures at a single institution were reviewed for patient characteristics, prior aortic repair history, aortic centerline of flow analysis, and procedural characteristics. SCI was defined as any lower extremity neurologic deficit that was not attributable to an intracranial process or peripheral neuropathy. Forty-three patient and procedural variables were evaluated individually for association with SCI. Those with the strongest relationships to SCI ( P < .1) were included in a multivariable logistic regression model, and a stepwise variable elimination algorithm was bootstrapped to derive a best subset of predictors from this model. Results From 2002 to 2013, 741 patients underwent TEVAR for various indications, and 68 (9.2%) developed SCI (permanent: n = 38; 5.1%). Because of the lack of adequate imaging for centerline analysis, 586 patients (any SCI, n = 43; 7.4%) were subsequently analyzed. Patients experiencing SCI after TEVAR were older (SCI, 72 ± 11 years; no SCI, 65 ± 15 years; P < .0001) and had significantly higher rates of multiple cardiovascular risk factors. The stepwise selection procedure identified five variables as the most important predictors of SCI: age (odds ratio OR multiplies by 1.3 per 10 years; 95% confidence interval CI, 0.9-1.8, P = .06), aortic coverage length (OR multiplies by 1.3 per 5 cm; CI, 1.1-1.6; P = .002), chronic obstructive pulmonary disease (OR, 1.9; CI, 0.9-4.1; P = .1), chronic renal insufficiency (creatinine concentration ≥ 1.6 mg/dL; OR, 1.9; CI, 0.8-4.2; P = .1), and hypertension (defined as chart history or medication; OR, 6.4; CI, 2.6-18; P < .0001). A logistic regression model with just these five covariates had excellent discrimination (area under the receiver operating characteristic curve = .83) and calibration ( χ2 = 9.8; P = .28). Conclusions This analysis generated a simple model that reliably predicts SCI after TEVAR. This clinical tool can assist decision-making about when to proceed with TEVAR, guide discussions about intervention risk, and help determine when maneuvers to mitigate SCI risk should be implemented.
Objective Open surgical revascularization for subclavian artery occlusive disease (OD) has largely been supplanted by endovascular treatment despite the excellent long-term patency of bypass. The ...indications for carotid-subclavian bypass (C-SBP) and subclavian transposition (ST) have been recently expanded with the widespread application of thoracic endovascular aortic repair (TEVAR), primarily to augment proximal landing zones or treat endovascular failures. This study was performed to determine the outcomes of patients undergoing C-SBP/ST in the context of contemporary endovascular therapies and evolving indications. Methods A prospective database including all procedures performed at a single institution from 2002 to 2012 was retrospectively queried for patients who underwent subclavian revascularization for TEVAR or OD indications. Patient demographics and perioperative outcomes were recorded. Patency was determined by computed tomography angiography in the TEVAR group. Noninvasive studies were used for the OD patients. Life-table methods were used to estimate patency, reintervention, and survival. Results Of 139 procedures identified, 101 were performed for TEVAR and 38 for OD. All TEVAR patients underwent C-SBP/ST to augment landing zones (49% preoperative; 41% intraoperative), treat arm ischemia (8% postoperative), or for internal mammary artery salvage (2%). OD patients had a variety of indications, including failed stent/arm fatigue, 49%; asymptomatic >80% internal carotid stenosis with concurrent subclavian occlusion, 18%; symptomatic cerebrovascular OD, 13%; redo bypass, 8%; and coronary-subclavian steal, 5%. Differences in postoperative stroke and death, primary patency, or freedom from reintervention were not significant. The 30-day postoperative stroke, death, and combined stroke/death rates were, respectively, 10.8%, 5.8%, and 13.7% for the entire cohort; 8.9%, 7.1%, and 12.9% in TEVAR patients; and 15.8%, 2.6%, and 15.8% in OD patients. The 1- and 3-year primary patencies were, respectively, 94% and 94% for TEVAR and 93% and 73% for OD patients. Survival was similar between the groups, with an estimated survival rate of 88% at 1 year and 76% at 5 years. Conclusions Stroke risk in this contemporary series of C-SBP/ST performed for TEVAR and OD indications may be higher than previously reported in historical series. In TEVAR patients, this may be attributed to procedural complexity of the TEVAR in patients requiring subclavian revascularization. In OD patients, this is likely due to the changing patient population that requires more frequent concomitant carotid interventions. Despite the short-term morbidity, excellent bypass durability and equivalent long-term patient survival can be anticipated.