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Background: Implementation of an anesthesiology-led cardiac implantable electronic device (CIED) service can be viewed to have economic and efficiency challenges. This study evaluates the cost savings of an anesthesiology-led CIED service. Methods: A total of 830 patients presented in the pre-implementation period from 1 March 2016 to 31 December 2017, and 1981 patients presented in the post-implementation period from 1 January 2018 to 31 October 2021. Interrupted time-series analysis for single-group comparisons was used to evaluate the cost savings resulting from reduction in operating room (OR) start delays for patients with CIEDs. Results: OR start-time delay was reduced by 10.6 min (95%CI: −20.5 to −0.83), comparing pre- to post-implementation. For an OR cost of USD 45/min, we estimated the direct cost to the department to be USD 1.68/min. The intervention translated into a total cost reduction during the intervention period of USD 250,000 (USD 18,000 to USD 470,000) per year for the institution and USD 9800 (USD 730 to USD 17,000) per year for the department. The yearly cost of employing a full-time team of CIED specialists would have been USD 135,456. The service triggered electrophysiology consultation on 13 device malfunctions. Conclusions: An anesthesiology-led CIED service resulted in substantial cost savings, increased OR efficiency and patient safety.

DIAMOND-AF (DiamondTemp™ Ablation System for the Treatment of Paroxysmal Atrial Fibrillation) was a prospective, multicenter, noninferiority, randomized trial that compared the safety and effectiveness of the DTA system versus those of a force-sensing RF ablation system (control) for the treatment of patients with drug-refractory, recurrent, symptomatic paroxysmal atrial fibrillation (AF).Irrigated radiofrequency (RF) ablation catheters lose tissue temperature acuity, which is vital in assessing lesion formation. DiamondTemp Ablation (DTA) was designed to re-establish accurate tissue temperature measurements during ablation.A total of 482 patients with paroxysmal AF were randomized (239 DTA, 243 control) to undergo pulmonary vein isolation and were followed up at 23 sites. Patients were screened for disease progression, cardiac characteristics, and prior interventions. Primary endpoints were effectiveness (freedom from atrial arrhythmia recurrence) and safety (composite of procedure- and device-related serious adverse events).The primary safety event rate was 3.3% in the DTA group versus 6.6% in the control group (p 0.001 vs. 6.5% noninferiority margin). Primary effectiveness was met in 79.1% of DTA subjects and 75.7% of control subjects (p 0.001 vs. -12.5% noninferiority margin). Secondary endpoint analysis found that off-drug effectiveness favored DTA compared with the control (142 [59.4%] vs. 120 [49.4%], respectively; p = 0.03). Total RF time and individual RF ablation duration were significantly shorter with less saline infused through the DTA catheter (p 0.001). Both arms saw clinically meaningful improvements in quality of life at 12 months.Safety and efficacy of the DTA system proved noninferior to force-sensing RF ablation in a paroxysmal AF population. Efficiencies were observed using DTA with shorter total RF times, individual RF ablation durations, and less saline infusion. (DiamondTemp™ Ablation System for the Treatment of Paroxysmal Atrial Fibrillation; NCT03334630).

Summary Background Endovascular renal denervation reduces blood pressure in patients with mild-to-moderate hypertension, but its efficacy in patients with true resistant hypertension has not been shown. We aimed to assess the efficacy and safety of endovascular ultrasound renal denervation in patients with hypertension resistant to three or more antihypertensive medications. Methods In a randomised, international, multicentre, single-blind, sham-controlled trial done at 28 tertiary centres in the USA and 25 in Europe, we included patients aged 18–75 years with office blood pressure of at least 140/90 mm Hg despite three or more antihypertensive medications including a diuretic. Eligible patients were switched to a once daily, fixed-dose, single-pill combination of a calcium channel blocker, an angiotensin receptor blocker, and a thiazide diuretic. After 4 weeks of standardised therapy, patients with daytime ambulatory blood pressure of at least 135/85 mm Hg were randomly assigned (1:1) by computer (stratified by centres) to ultrasound renal denervation or a sham procedure. Patients and outcome assessors were masked to randomisation. Addition of antihypertensive medications was allowed if specified blood pressure thresholds were exceeded. The primary endpoint was the change in daytime ambulatory systolic blood pressure at 2 months in the intention-to-treat population. Safety was also assessed in the intention-to-treat population. This study is registered with ClinicalTrials.gov , NCT02649426 . Findings Between March 11, 2016, and March 13, 2020, 989 participants were enrolled and 136 were randomly assigned to renal denervation (n=69) or a sham procedure (n=67). Full adherence to the combination medications at 2 months among patients with urine samples was similar in both groups (42 [82%] of 51 in the renal denervation group vs 47 [82%] of 57 in the sham procedure group; p=0·99). Renal denervation reduced daytime ambulatory systolic blood pressure more than the sham procedure (−8·0 mm Hg [IQR –16·4 to 0·0] vs –3·0 mm Hg [–10·3 to 1·8]; median between-group difference –4·5 mm Hg [95% CI –8·5 to –0·3]; adjusted p=0·022); the median between-group difference was –5·8 mm Hg (95% CI –9·7 to –1·6; adjusted p=0·0051) among patients with complete ambulatory blood pressure data. There were no differences in safety outcomes between the two groups. Interpretation Compared with a sham procedure, ultrasound renal denervation reduced blood pressure at 2 months in patients with hypertension resistant to a standardised triple combination pill. If the blood pressure lowering effect and safety of renal denervation are maintained in the long term, renal denervation might be an alternative to the addition of further antihypertensive medications in patients with resistant hypertension. Funding ReCor Medical.

Introduction: Cardiac device extraction procedures are associated with increased risk of in-hospital mortality. The objective of this study was to determine risk factors for in-hospital mortality of patients undergoing cardiac device extraction. Methods: We studied patients undergoing cardiac device removal between January 2016 and December 2019 at a single tertiary care center. Baseline patient characteristics, comorbidities, and preoperative laboratory data were obtained by database query (Table 1) . The outcome of interest was in-hospital death following cardiac device extraction. Odds ratios (OR) and confidence intervals (CI) were used to measure relationships between exposures and the main outcome. Results: Our cohort consisted of 333 patients who underwent cardiac device extraction procedures. Cardiac device infection was the indication for procedure in 48% of patients (n=161). In-hospital mortality occurred in 9% of patients (n=29). Patients that died inpatient post-operatively were more likely to be male gender (OR 3.59, 95% CI [1.2, 10.6], p = 0.02), have acute kidney failure (OR 3.17, 95% CI [1.42, 7.05], p = 0.005), have anemia (OR 3.22, 95% CI [1.49, 6.99], p = 0.003), or have a diagnosis of severe malnutrition (OR 2.88, 95% CI [1.26, 6.58], p = 0.01). In a subgroup analysis, patients with diabetes undergoing extraction for infectious reasons had an increased risk of in-hospital mortality (OR 4.36, 95% CI [1.54, 12.34], p = 0.005). Conclusion: Patients undergoing cardiac device extraction are high risk for in-hospital mortality. Patients experiencing in-hospital mortality were more likely to be male, have acute renal failure, anemia and severe malnutrition. Careful analysis of preoperative risk factors, laboratory data, and nutritional status can help stratify risk for patients and providers.

The COVID-19 global pandemic presents with a wide range of clinical manifestations, including biochemical, echocardiographic, and electrocardiographic (ECG) evidence of myocardial involvement ([1–3][1]). However, the occurrence of atrial arrhythmias in patients with this infection and how these

Aims The objective of this study was to verify acute safety, performance, and usage of a novel ultra-high density mapping system in patients undergoing ablation procedure in a real-world clinical setting. Methods and results The TRUE HD study enrolled patients undergoing catheter ablation with mapping for all arrhythmias (excluding de novo atrial fibrillation) who were followed for 1 month. Safety was determined by collecting all serious adverse events and adverse events associated with the study devices. Performance was determined as the composite of: ability to map the arrhythmia/substrate, complete the ablation applications, arrhythmia termination (where applicable), and ablation validation. Use of mapping system in the ablation validation workflow was also evaluated. Among the 519 patients who underwent a complete (504) or attempted (15) procedure, 21 (4%) serious ablation-related complications were collected, with 3 (0.57%) potentially related to the mapping catheter. Four hundred and twenty treated patients resulted in a successful procedure confirmed by arrhythmia-specific validation techniques (83.3%; 95% confidence interval: 79.8–86.5%). A total of 1419 electroanatomical maps were created with a median acquisition time of 9:23 min per map. Of these, 372 maps in 222 (44%) patients were collected for ablation validation purposes. Following validation mapping, 162/222 (73%) patients required additional ablation. Conclusion In the TRUE HD study mapping was associated with rates of acute success and complications consistent with previously published reports. Importantly, a low percentage of events (0.57%) was attributed to the mapping catheter. When performed, validation mapping was useful for identifying additional targets for ablation in the majority of patients.

Background: The multicenter, international, randomized, blinded, sham-controlled RADIANCE-HTN SOLO trial (A Study of the ReCor Medical Paradise System in Clinical Hypertension) demonstrated a 6.3 mm Hg greater reduction in daytime ambulatory systolic blood pressure (BP) at 2 months by endovascular ultrasound renal denervation (RDN) compared with a sham procedure among patients not treated with antihypertensive medications. We report 6-month results after the addition of a recommended standardized stepped-care antihypertensive treatment to the randomized endovascular procedure under continued blinding to initial treatment. Methods: Patients with a daytime ambulatory BP ≥135/85 mm Hg and Results: A total of 69/74 RDN patients and 71/72 sham patients completed the 6-month ambulatory BP measurement. At 6 months, 65.2% of patients in the RDN group were treated with the standardized stepped-care antihypertensive treatment versus 84.5% in the sham group ( P =0.008), and the average number of antihypertensive medications and defined daily dose were less in the RDN group than in the sham group (0.9±0.9 versus 1.3±0.9, P =0.010 and 1.4±1.5 versus 2.0±1.8, P =0.018; respectively). Despite less intensive standardized stepped-care antihypertensive treatment, RDN reduced daytime ambulatory systolic BP to a greater extent than sham (−18.1±12.2 versus −15.6±13.2 mm Hg, respectively; difference adjusted for baseline BP and number of medications: −4.3 mm Hg, 95% confidence interval, −7.9 to −0.6, P =0.024). There were no major adverse events in either group through 6 months. Conclusions: The BP-lowering effect of endovascular ultrasound RDN was maintained at 6 months with less prescribed antihypertensive medications compared with a sham control. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02649426.

Summary Background Early studies suggest that radiofrequency-based renal denervation reduces blood pressure in patients with moderate hypertension. We investigated whether an alternative technology using endovascular ultrasound renal denervation reduces ambulatory blood pressure in patients with hypertension in the absence of antihypertensive medications. Methods RADIANCE-HTN SOLO was a multicentre, international, single-blind, randomised, sham-controlled trial done at 21 centres in the USA and 18 in Europe. Patients with combined systolic–diastolic hypertension aged 18–75 years were eligible if they had ambulatory blood pressure greater than or equal to 135/85 mm Hg and less than 170/105 mm Hg after a 4-week discontinuation of up to two antihypertensive medications and had suitable renal artery anatomy. Patients were randomised (1:1) to undergo renal denervation with the Paradise system (ReCor Medical, Palo Alto, CA, USA) or a sham procedure consisting of renal angiography only. The randomisation sequence was computer generated and stratified by centres with randomised blocks of four or six and permutation of treatments within each block. Patients and outcome assessors were blinded to randomisation. The primary effectiveness endpoint was the change in daytime ambulatory systolic blood pressure at 2 months in the intention-to-treat population. Patients were to remain off antihypertensive medications throughout the 2 months of follow-up unless specified blood pressure criteria were exceeded. Major adverse events included all-cause mortality, renal failure, an embolic event with end-organ damage, renal artery or other major vascular complications requiring intervention, or admission to hospital for hypertensive crisis within 30 days and new renal artery stenosis within 6 months. This study is registered with ClinicalTrials.gov, number NCT02649426. Findings Between March 28, 2016, and Dec 28, 2017, 803 patients were screened for eligibility and 146 were randomised to undergo renal denervation (n=74) or a sham procedure (n=72). The reduction in daytime ambulatory systolic blood pressure was greater with renal denervation (−8·5 mm Hg, SD 9·3) than with the sham procedure (−2·2 mm Hg, SD 10·0; baseline-adjusted difference between groups: −6·3 mm Hg, 95% CI −9·4 to −3·1, p=0·0001). No major adverse events were reported in either group. Interpretation Compared with a sham procedure, endovascular ultrasound renal denervation reduced ambulatory blood pressure at 2 months in patients with combined systolic–diastolic hypertension in the absence of medications. Funding ReCor Medical.

Background Despite cardiac resynchronization therapy (CRT), some patients with heart failure progress and undergo left ventricular assist device (LVAD) implantation. Management of CRT after LVAD implantation has not been well studied. The purpose of this study was to determine whether RV pacing or biventricular pacing measurably affects acute hemodynamics in patients with an LVAD and a CRT device. Methods and Results Seven patients with CRT and LVAD underwent right heart catheterization. Pressures and oximetry were measured and LVAD parameters were recorded during 3 different conditions: RV pacing alone, biventricular pacing, and intrinsic atrioventricular conduction. Paired t tests were used to evaluate changes within subjects. There were no significant changes in right atrial pressure, pulmonary arterial pressures, pulmonary capillary wedge pressure, cardiac index, or any LVAD parameter (P > .05). Conclusions Our data suggest that CRT probably has no acute hemodynamic effect in patients with LVADs, but further study is needed.

Dabigatran versus Warfarin for AF AblationBackground Uninterrupted oral anticoagulant (OA) therapy with warfarin has become the standard of care at many centers performing catheter ablation of atrial fibrillation (AF). Compared with warfarin, dabigatran, a direct thrombin inhibitor, has been demonstrated to reduce the risk of stroke in nonvalvular AF with similar bleeding risk. Few data exist on the safety profile of uninterrupted dabigatran therapy during AF ablation. Methods We compared the safety and efficacy of uninterrupted OA therapy with either warfarin or dabigatran in all patients undergoing AF catheter ablation at the University of Alabama at Birmingham between November 1, 2010 and January 31, 2012. All patients underwent a transesophageal echocardiogram (TEE) on the day of their ablation procedure to assess for the presence of intracardiac thrombi. All complications were identified and classified as bleeding, thromboembolic events, or other. Results There were 212 patients in the dabigatran group and 251 patients in the warfarin group. The groups were well matched. There were 3 complications in the dabigatran group and 6 in the warfarin group (P = 0.45). There were 2 bleeding complications in the dabigatran group and 6 in the warfarin group (P = 0.23). There was one thromboembolic complication (a possible TIA) in the dabigatran group and none in the warfarin group (P = 0.28). Conclusion The administration of dabigatran is as safe and effective as warfarin for uninterrupted OA therapy during catheter ablation of AF.

Thromboembolic cerebrovascular accident remains a rare but potentially devastating complication of catheter-based atrial fibrillation (AF) ablation. Uninterrupted oral anticoagulant therapy with warfarin has become the standard of care when performing catheter-based AF ablation. Compared with warfarin, apixaban, a factor Xa inhibitor, has been shown to reduce the risk of stroke and major bleeding in nonvalvular AF. With an increase in apixaban use for stroke prophylaxis in patients with AF, there is an increased interest in the safety and efficacy of uninterrupted apixaban therapy during AF ablation. We compared the safety and efficacy of uninterrupted OA therapy with either warfarin or apixaban in all patients who underwent catheter-based AF ablation at the University of Alabama at Birmingham and at Augusta University Medical Center from January 7, 2013, to February 25, 2016. All patients underwent a transesophageal echocardiogram on the day of their ablation to assess for the presence of intracardiac thrombi. All complications were identified and classified as bleeding, thromboembolic events, or other. A total of 627 patients were analyzed as described earlier. There were 310 patients in the warfarin group and 317 patients in the apixaban group. There were 8 complications in the warfarin group and 5 complications in the apixaban group (p = 0.38). There were no thromboembolic complications in either group. In conclusion, the use of apixaban is as safe and effective as warfarin for uninterrupted OA therapy during catheter-based ablation of AF.

Backgrounds— Idiopathic ventricular arrhythmias (VAs) originating from the left ventricular outflow tract (LVOT) sometimes require catheter ablation from both the endocardial and epicardial sides for their elimination, suggesting the presence of intramural VA foci. This study investigated the prevalence and electrocardiographic and electrophysiological characteristics of these idiopathic intramural LVOT VAs when compared with the idiopathic endocardial and epicardial LVOT VAs. Methods and Results— We studied 82 consecutive VAs with origins in the aortomitral continuity (n=30), LV summit (n=34), and intramural site (n=18). The maximum deflection index (the time to the maximum deflection in the precordial leads/QRS duration) was the largest in LV summit VAs (0.52±0.07), smallest in aortomitral continuity VAs (0.45±0.06), and midrange in intramural VAs (0.49±0.05). The electrocardiographic and electrophysiological characteristics of the intramural LVOT VAs were similar to those of the aortomitral continuity VAs. The intramural LVOT VAs exhibited a significantly smaller R-wave amplitude ratio in leads III to II, and ratio of the Q-wave amplitude in leads aVL to aVR, and a significantly earlier and later local ventricular activation time relative to the QRS onset at the His bundle and successful ablation sites than the LV summit VAs, respectively. Conclusions— Intramural sites account for a significant proportion of LVOT VAs. The electrocardiographic and electrophysiological characteristics of the idiopathic intramural LVOT VAs were midrange between those of the idiopathic endocardial and epicardial LVOT VAs, and more similar to those of the idiopathic endocardial LVOT VAs than those of the idiopathic epicardial LVOT VAs.

The case of a patient who presented with angina following a coronary artery bypass (CABG) operation during which the left internal mammary artery was inadvertently anastomosed to a cardiac vein is presented. The literature concerning previously reported cases of aortocoronary arteriovenous fistulas (ACAVF) due to inadvertent grafting of a coronary vein is reviewed and the significance of this complication is discussed. ACAVF due to inadvertent grafting of a coronary vein is a rare complication of CABG and may be a more common cause of graft failure than has previously been recognized. Distortion of cardiac anatomy, the presence of epicardial fat, and an intramyocardial course of the artery intended for grafting are predisposing factors. Some patients present with angina pectoris and heart failure whereas others have no symptoms. The diagnostic test of choice is coronary angiography. Cardiac MRI and CT have a limited role due to the smaller size and the more clearly defined course of these fistulas. Asymptomatic patients are simply observed since spontaneous closure of these fistulas is reported. Symptomatic patients can be treated with combined medical management and percutaneous methods.

We read with great interest the study by Aragam et al. [(1)][1] and the editorial comment by Thomas [(2)][2]. Indeed, cardiac rehabilitation (CR) is an important preventive measure that remains underused in the United States [(3,4)][3]. Intuitively, the first step in improving use of CR is to

Introduction: Hemodialysis patients (HD pts) with atrial fibrillation (AF) have increased risk of stroke. The HASBLED (Hypertension (HTN), Abnl Renal/Liver Function, Stroke, Bleeding Hx, Labile INR, Elderly, Drugs/Alcohol) risk score predicts bleeding in the general AF population. It is unknown whether the HASBLED score can be applied to HD pts who are at additional bleeding risk due to uremic platelet dysfunction and the regular use of heparin. Hypothesis: To address this question, we queried the United States Renal Data System (USRDS) for bleeding events in HD pts with AF, and correlated those events with a modified HASBLED (mHASBLED) score. Methods: All incident HD pts with AF from the USRDS for 2006-2010 were queried for major bleeding events and mHASBLED parameters using ICD-9 diagnosis codes and data from CMS form 2728. For mHASBLED, the HTN parameter was defined as "HTN as the cause of renal failure", and labile INR as > 16 INRs/yr, but all other parameters could be derived from the dataset. Logistic regression (LR) analysis was used to estimate the odds ratio (OR) for the mHASBLED score to predict major bleeding events. Results: 74,631 HD pts had AF, and 9.8% had a major bleeding event (GI bleeding and hemorrhagic stroke). By univariate analysis, those who bled were more likely to be elderly, have an underlying cause of renal disease due to HTN, prior bleeding event, hepatitis C, labile INR, and be on oral anticoagulants. By LR, variables with the greatest impact on bleeding were HTN as a cause of underlying renal disease, prior bleeding history, and labile INR (OR of 1.10, 2.20 and 2.24, respectively). The OR for bleeding events increased by 1.28 for each unit increase in mHASBLED. Older age, prior stroke, abnormal renal or liver function, and drug use had the least effect. Note that the lowest possible score in this cohort is 1, given that all patients had renal failure. Conclusions: In HD pts with AF, the mHASBLED predicts major bleeding events. The universal presence of renal disease, and the lack of specific clinical data from the USRDS may limit the clinical precision of a given score, however mHASBLED may remain a useful indicator of bleeding risk in this population.

Introduction Cardiac implantable electronic devices (CIED) are increasingly being used in end-stage renal disease (ESRD) patients. These patients have a high risk of device infection. Objectives To study the optimal management of device infections in patients with ESRD. Method We used the United States Renal Data System (USRDS) to assess the presence of a CIED and associated comorbidities, risk factors for infection, and mortality following device extraction or medical management in ESRD patients with CIED infection. Univariable, multivariable, and survival analyses were performed using USRDS data from 2005 to 2009. Results Of 546,769 patients, 6.4% had CIED and 8.0% of those developed CIED infection. The major risk factors for device infection were black race, temporary dialysis catheter, and body mass index >25. Patients with artificial valves were excluded from the analysis. Only 28.4% of infected CIED were removed. CIED removal was more common in those with congestive heart failure. The median time to death following diagnosis of a CIED infection was 15.7 months versus 9.2 months for those treated via device extraction versus medical-only therapy (hazard ratio: 0.75; 95% confidence interval: 0.68–0.82). Conclusion Patients with ESRD and infected CIEDs have a poor prognosis. Rates of device extraction are low, but this strategy appears to be associated with modest improvement in survival.

Cardiac rehabilitation (CR) is an effective preventive measure that remains underutilised in the United States. The study aimed to determine the CR referral rate (RR) after percutaneous coronary intervention (PCI) at an academic tertiary care centre, identify barriers to referral, and evaluate awareness of CR benefits and indications (CRBI) among cardiologists. Subsequently, it aimed to evaluate if an intervention consisting of physicians' education about CRBI and implementation of a formal CR referral system could improve RR and consequently participation rate (PR).Data were retrospectively collected for all consecutive patients who underwent PCI over 12 months. Referral rate was determined and variables were compared for differences between referred and non-referred patients. A questionnaire was distributed among the physicians in the Division of Cardiology to assess awareness of CRBI and referral practice patterns. After implementation of the intervention, data were collected retrospectively for consecutive patients who underwent PCI in the following six months. Referral rate and changes in PRs were determined.Prior to the intervention, RR was 17.6%. Different barriers were identified, but the questionnaire revealed lack of physicians' awareness of CRBI and inconsistent referral patterns. After the intervention, RR increased to 88.96% (Odds Ratio 37.73, 95% CI 21.34-66.70, p0.0001) and PR increased by 32.8% to reach 26%. Personal endorsement of CRBI by cardiologists known to patients increased CR program graduation rate by 35%.Cardiologists' awareness of CRBI increases CR RR and their personal endorsement improves PR and compliance. Education of providers and implementation of a formal referral system can improve RR and PR.

Backgrounds— Idiopathic ventricular arrhythmias (VAs) originating from the left ventricular outflow tract (LVOT) sometimes require catheter ablation from the endocardial and epicardial sides for their elimination, suggesting the presence of intramural VA foci. This study investigated the efficacy of sequential and simultaneous unipolar radiofrequency catheter ablation from the endocardial and epicardial sides in treating intramural LVOT VAs. Methods and Results— Fourteen consecutive LVOT VAs, which required sequential or simultaneous irrigated unipolar radiofrequency ablation from the endocardial and epicardial sides for their elimination, were studied. The first ablation was performed at the site with the earliest local ventricular activation and best pace map on the endocardial or epicardial side. When the first ablation was unsuccessful, the second ablation was delivered on the other surface. If this sequential unipolar ablation failed, simultaneous unipolar ablation from both sides was performed. The first ablation was performed on the epicardial side in 9 VAs and endocardial side in 5 VAs. The intramural LVOT VAs were successfully eliminated by the sequential (n=9) or simultaneous (n=5) unipolar catheter ablation. Simultaneous ablation was most likely to be required for the elimination of the VAs when the distance between the endocardial and epicardial ablation sites was >8 mm and the earliest local ventricular activation time relative to the QRS onset during the VAs of Conclusions— LVOT VAs originating from intramural foci could usually be eliminated by sequential unipolar radiofrequency ablation and sometimes required simultaneous ablation from both the endocardial and epicardial sides.

Microdynamic systems have been studied for a number of years. Only limited work, however, has been completed on integrating microdynamic components into systems that satisfy mechanical tasks on macroscopic scales. In this paper, we describe microdynamic components needed to produce a surface which is actively deformable on local scales. In particular, we consider the design and demonstration of smart journal and thrust bearings capable of using embedded sensors and actuators to change dynamically the surface geometry. The ability actively to deform bearing surfaces allows for the design of bearings which are less prone to failure, the design of bearings with greater load-carrying abilities, and a fundamental study of the effect of surface geometries and fluid conditions on bearing performance, such as start-up and shut-down conditions. Some results of our new bearing designs are presented, focusing on numerical bearing models, sensor and actuator design and fabrication, and physical experimentation.

The focus of new research efforts to improve the morbidity and mortality associated with acute myocardial infarction (AMI) has turned to adjuvant agents that show promise of improving outcomes following coronary thrombolysis. We enrolled 162 patients with AMI in a randomized trial comparing front-loaded tissue-plasminogen activator (t-PA) plus weight-adjusted heparin with anisoylated plasminogen streptokinase activator complex (APSAC) without heparin as well as standarddose (325 mg) and low-dose (81 mg) aspirin. The primary end point was an in-hospital morbidity profile; secondary end points were clinical and angiographic patency and hemorrhagic events. Selected sites performed an electrocardiographic substudy to determine the time to 50% ST-segment recovery and the time to steady state. Although the trial was terminated when the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries-I trial showed that t-PA had a significant mortality advantage over streptokinase, important trends were evident. Patients given t-PA and heparin were better anticoagulated (p = 0.001), yet AP-SAC-treated patients had more bleeding complications. The primary end point favored t-PA (25.4% vs 31.3%), and the secondary end points were similar in both groups. In the electrocardiographic substudy, the t-PA group achieved both 50% ST-segment recovery and steady-state recovery sooner than the APSAC group. Patients taking low-dose aspirin had lower in-hospital mortality and less recurrent ischemia but more strokes than the standard-dose aspirin group. Thus, this trial demonstrated trends favoring front-loaded t-PA with weight-adjusted heparin over APSAC without heparin in the treatment of AMI. The use of low-dose aspirin did not appear to impose a loss of protection from adverse events, nor did standard-dose aspirin increase serious bleeding.

Uninterrupted oral anticoagulant (OA) therapy with warfarin has become the standard of care at many centers performing catheter ablation of atrial fibrillation (AF). Compared with warfarin, dabigatran, a direct thrombin inhibitor, has been demonstrated to reduce the risk of stroke in nonvalvular AF with similar bleeding risk. Few data exist on the safety profile of uninterrupted dabigatran therapy during AF ablation.We compared the safety and efficacy of uninterrupted OA therapy with either warfarin or dabigatran in all patients undergoing AF catheter ablation at the University of Alabama at Birmingham between November 1, 2010 and January 31, 2012. All patients underwent a transesophageal echocardiogram (TEE) on the day of their ablation procedure to assess for the presence of intracardiac thrombi. All complications were identified and classified as bleeding, thromboembolic events, or other.There were 212 patients in the dabigatran group and 251 patients in the warfarin group. The groups were well matched. There were 3 complications in the dabigatran group and 6 in the warfarin group (P = 0.45). There were 2 bleeding complications in the dabigatran group and 6 in the warfarin group (P = 0.23). There was one thromboembolic complication (a possible TIA) in the dabigatran group and none in the warfarin group (P = 0.28).The administration of dabigatran is as safe and effective as warfarin for uninterrupted OA therapy during catheter ablation of AF.

Background: Triaging of patients with chest pain in the emergency department is costly and time consuming. Human fatty acid binding protein is an emerging biomarker which is known to be sensitive marker of early myocardial cell injury. We prospectively investigated the usefulness of serial Human Fatty Acid Binding Protein determination in the evaluation of acute chest pain in patients arriving at the emergency department. Methods: In 47 consecutive patients who had acute chest pain for less than 12 hours without electrocardiographic changes and initial negative troponin elevation, serial human fatty acid binding protein was determined. Testing was performed at enrollment and 1 hour later using a point-of-care assay. Serial troponin determination and ischemia workup with stress testing was performed according to standard protocols. Results: Human fatty acid binding protein was positive in 7/47 (14.9%) patients while troponin was positive in 4 (8.5%) patients. There were 2/47 (4.3%) patients with angiographically significant stenosis. The sensitivity and specificity of human fatty acid binding protein was 75% and 83.7%, respectively compared to serial troponin measurement. The positive and negative predictive value of human fatty acid binding protein was 30% and 93.3%, respectively. The diagnostic accuracy was 82.9%. Conclusion: Point-of-care serial human fatty acid binding protein testing for early detection of myocardial cell injury has inferior diagnostic performance compared to serial troponin determination. The addition of human fatty acid binding protein measurement to troponin did not improve the diagnostic performance of troponin. Further assay validation and a larger study cohort is required to confirm these findings.

The CHA2DS2VASc score predicts stroke occurrence and mortality in atrial fibrillation (AF) patients. AF and End Stage Renal Disease (ESRD) share many risk factors including heart failure, hypertension, and diabetes. Patients with ESRD and AF may exhibit some or all of these risk factors, suggesting