A H Kadish

Northwestern University, Evanston, Illinois, United States

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Publications (320)2025.6 Total impact

  • Circulation 01/2014; 129(4):516-26. · 15.20 Impact Factor
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    ABSTRACT: To provide a meta-analysis to estimate the performance of 12 commonly reported risk stratification tests as predictors of arrhythmic events in patients with NIDCM. Multiple techniques have been assessed as predictors of death due to ventricular tachyarrhythmias/sudden death in patients with non-ischemic dilated cardiomyopathy (NIDCM). Forty-five studies enrolling 6088 patients evaluating the association between arrhythmic events and predictive tests (baroreflex sensitivity, heart rate turbulence, heart rate variability, left ventricular end diastolic dimension, left ventricular ejection fraction, electrophysiology study, non-sustained ventricular tachycardia, left bundle branch block, signal-averaged electrocardiogram, fragmented QRS, QRS-T angle, and T-wave alternans) were included. Raw event rates were extracted and meta-analysis was performed using mixed effects methodology. We also used trim-and-fill method to estimate the influence of missing studies on the results. Patients were 52.8±14.5 years old and 77% were male. LVEF was 30.6±11.4%. Test sensitivities ranged from 28.8% to 91.0%; specificities from 36.2% to 87.1%; odds ratios from 1.5 to 6.7. OR was highest for fragmented QRS and TWA (OR=6.73 and 4.66, 95% confidence interval 3.85-11.76 and 2.55-8.53, respectively) and lowest for QRS duration (OR=1.51, 1.13-2.01). None of the autonomic tests (HRV, HRT, BRS) were significant predictors of arrhythmic outcomes. Accounting for publication bias reduced the odds ratios for the various predictors but did not eliminate the predictive association. Techniques incorporating functional parameters, depolarization abnormalities, repolarization abnormalities, and arrhythmic markers provide only modest risk stratification for SCD in patients with NIDCM. It is likely that combinations of tests will be required to optimize risk stratification in this population.
    Journal of the American College of Cardiology 01/2014; · 14.09 Impact Factor
  • International journal of cardiology 01/2014; · 7.08 Impact Factor
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    ABSTRACT: Background The benefit of a primary prevention implantable cardioverter-defibrillator (ICD) among patients with chronic kidney disease is uncertain. Study Design Meta-analysis of patient-level data from randomized controlled trials. Setting & Population Patients with symptomatic heart failure and left ventricular ejection fraction < 35%. Selection Criteria for Studies From 7 available randomized controlled studies with patient-level data, we selected studies with available data for important covariates. Studies without patient-level data for baseline estimated glomerular filtration rate (eGFR) were excluded. Intervention Primary prevention ICD versus usual care effect modification by eGFR. Outcomes Mortality, rehospitalizations, and effect modification by eGFR. Results We included data from the Multicenter Automatic Defibrillator Implantation Trial I (MADIT-I), MADIT-II, and the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). 2,867 patients were included; 36.3% had eGFR < 60 mL/min/1.73 m2. Kaplan-Meier estimate of the probability of death during follow-up was 43.3% for 1,334 patients receiving usual care and 35.8% for 1,533 ICD recipients. After adjustment for baseline differences, there was evidence that the survival benefit of ICDs in comparison to usual care depends on eGFR (posterior probability for null interaction P < 0.001). The ICD was associated with survival benefit for patients with eGFR ≥ 60 mL/min/1.73 m2 (adjusted HR, 0.49; 95% posterior credible interval, 0.24-0.95), but not for patients with eGFR < 60 mL/min/1.73 m2 (adjusted HR, 0.80; 95% posterior credible interval, 0.40-1.53). eGFR did not modify the association between the ICD and rehospitalizations. Limitations Few patients with eGFR < 30 mL/min/1.73 m2 were available. Differences in trial-to-trial measurement techniques may lead to residual confounding. Conclusions Reductions in baseline eGFR decrease the survival benefit associated with the ICD. These findings should be confirmed by additional studies specifically targeting patients with varying eGFRs.
    American Journal of Kidney Diseases 01/2014; · 5.29 Impact Factor
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    ABSTRACT: Cardiovascular imaging studies generate a wealth of data which is typically used only for individual study endpoints. By pooling data from multiple sources, quantitative comparisons can be made of regional wall motion abnormalities between different cohorts, enabling reuse of valuable data. Atlas-based analysis provides precise quantification of shape and motion differences between disease groups and normal subjects. However, subtle shape differences may arise due to differences in imaging protocol between studies. A mathematical model describing regional wall motion and shape was used to establish a coordinate system registered to the cardiac anatomy. The atlas was applied to data contributed to the Cardiac Atlas Project from two independent studies which used different imaging protocols: steady state free precession (SSFP) and gradient recalled echo (GRE) cardiovascular magnetic resonance (CMR). Shape bias due to imaging protocol was corrected using an atlas-based transformation which was generated from a set of 46 volunteers who were imaged with both protocols. Shape bias between GRE and SSFP was regionally variable, and was effectively removed using the atlas-based transformation. Global mass and volume bias was also corrected by this method. Regional shape differences between cohorts were more statistically significant after removing regional artifacts due to imaging protocol bias. Bias arising from imaging protocol can be both global and regional in nature, and is effectively corrected using an atlas-based transformation, enabling direct comparison of regional wall motion abnormalities between cohorts acquired in separate studies.
    Journal of Cardiovascular Magnetic Resonance 09/2013; 15(1):80. · 4.44 Impact Factor
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    ABSTRACT: A collaborative framework was initiated to establish a community resource of ground truth segmentations from cardiac MRI. Multi-site, multi-vendor cardiac MRI datasets comprising 95 patients (73 men, 22 women; mean age 62.73±11.24years) with coronary artery disease and prior myocardial infarction, were randomly selected from data made available by the Cardiac Atlas Project (Fonseca et al., 2011). Three semi- and two fully-automated raters segmented the left ventricular myocardium from short-axis cardiac MR images as part of a challenge introduced at the STACOM 2011 MICCAI workshop (Suinesiaputra et al., 2012). Consensus myocardium images were generated based on the Expectation-Maximization principle implemented by the STAPLE algorithm (Warfield et al., 2004). The mean sensitivity, specificity, positive predictive and negative predictive values ranged between 0.63 and 0.85, 0.60 and 0.98, 0.56 and 0.94, and 0.83 and 0.92, respectively, against the STAPLE consensus. Spatial and temporal agreement varied in different amounts for each rater. STAPLE produced high quality consensus images if the region of interest was limited to the area of discrepancy between raters. To maintain the quality of the consensus, an objective measure based on the candidate automated rater performance distribution is proposed. The consensus segmentation based on a combination of manual and automated raters were more consistent than any particular rater, even those with manual input. The consensus is expected to improve with the addition of new automated contributions. This resource is open for future contributions, and is available as a test bed for the evaluation of new segmentation algorithms, through the Cardiac Atlas Project (www.cardiacatlas.org).
    Medical image analysis 09/2013; 18(1):50-62. · 3.09 Impact Factor
  • Heart rhythm: the official journal of the Heart Rhythm Society 07/2013; · 4.56 Impact Factor
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    ABSTRACT: BACKGROUND: As LVEF may improve, worsen, or stay the same over time, patients' prognosis may also be expected to change related to change in LVEF, among other factors. OBJECTIVE: To evaluate the effect of LVEF change on outcome in DEFINITE. METHODS: DEFINITE enrolled patients with nonischemic cardiomyopathy with LVEF<36%, history of symptomatic heart failure, and the presence of significant ventricular ectopic activity. Follow-up LVEF measurements were obtained annually in only a minority (17%) of trial participants. This study therefore evaluated survival and arrhythmic endpoints in patients whose LVEF was re-assessed between 90-730 days after enrollment. RESULTS: During the 90-730 days post-randomization period, 187/449 enrolled patients (42%) who survived past 90 days had at least one follow-up LVEF measurement; these patients tended to be younger, white, diabetic, had better 6-minute walk tests, higher BMI, were more likely to have appropriate shocks, and had fewer deaths compared to those without follow-up LVEF measurements. Patients whose LVEF improved had reduced mortality compared to patients who had a decrease in LVEF (HR=0.09, 95% CI 0.02-0.39; p=0.001). Survival free of appropriate shocks was not significantly related to LVEF improvement during follow-up. CONCLUSIONS: LVEF improvement was associated with improved survival, but not with a significant decrease in appropriate shocks. These data highlight that appropriate caution should be taken not to extrapolate the positive effect of improved LVEF to elimination of arrhythmic events.
    Heart rhythm: the official journal of the Heart Rhythm Society 02/2013; · 4.56 Impact Factor
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    ABSTRACT: BACKGROUND: Whether there is an optimal time to place an implantable cardioverter-defibrillator (ICD) more than 40 days after myocardial infarction (MI) in guideline-eligible patients is unknown. OBJECTIVE: To evaluate the impact of time from MI to randomization on mortality, re-hospitalizations, and complications. METHODS: Individual data on patients enrolled in 9 primary prevention ICD trials were provided. Clinical trials were eligible for the current analysis if they enrolled patients with an MI more than 40 days prior to randomization to primary prevention ICD therapy versus usual care: MADIT-I, MUSTT, MADIT-II, and SCD-HeFT. RESULTS: ICD recipients died less frequently than non-recipients at 5 years across all subgroups of time from MI to randomization. In unadjusted Cox proportional hazards regression, a survival benefit was evident in most subgroups. Adjusted Bayesian Weibull survival modeling yielded hazard ratio (HR) 0.50, 95% posterior credible interval [PCI] 0.20-1.25 41-180 days after MI; HR 0.98, 95% PCI 0.37-2.37 181-365 days after MI; HR 0.22, 95% PCI 0.07-0.59 >1-2 years after MI; HR 0.42, 95% PCI 0.17-0.90 >2-5 years after MI; HR 0.55, 95% PCI 0.25-1.15 >5-10 years after MI; and HR 0.48, 95% PCI 0.20-1.02 > 10 years after MI. There was no evidence of an interaction between time from MI and all-cause mortality, re-hospitalizations, or complications. CONCLUSIONS: In this meta-analysis, there was scant evidence that the efficacy of primary prevention ICD therapy and no evidence that the risks of re-hospitalizations or complications are dependent on time to implantation more than 40 days after MI.
    Heart rhythm: the official journal of the Heart Rhythm Society 02/2013; · 4.56 Impact Factor
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    ABSTRACT: Peri-infarct border zone (BZ) as quantified by late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (MRI) has been proposed as a risk stratification tool, and is associated with increased mortality. BZ has been measured by various methods in the literature. We assessed which BZ analysis best predicts inducible arrhythmia during electrophysiological study (EPS). LGE was performed in 47 patients with coronary artery disease referred for EPS to assess for ventricular tachycardia (VT). LGE data was analyzed for BZ quantification by 3 previously published methods. Method I (BZ-I) used pixels 2-3 standard deviations over the mean of normal tissue, expressed as % of left ventricular mass, Method II (BZ-II, as described by Yan) and Method III (BZ-III, as described by Schmidt). EPS results were classified as negative (non-inducible) or positive (monomorphic VT - MVT). There were 47 subjects-age 61.7 years, 72% male. During EPS, 20 patients were non-inducible and 18 had induced MVT. Ejection fraction was not significantly different between non-inducible patients and those with MVT (34.1% vs. 28.5%, p = 0.13). BZ-I was significantly different (1.4% vs. 2.6%, p = 0.001), but not BZ-II (7.9% vs. 6.9%, p = 0.68) or BZ-III (2.7 g vs. 2.1 g, p = 0.88). Multivariate analysis demonstrated that only BZ-I was an independent predictor of EPS outcome after controling for infarct size (OR 1.97 per % change, 95% CI 1.04-3.73, p = 0.04). This study demonstrates significant variability between the published methods for measuring BZ. Also, BZ-I is a stronger predictor of inducible MVT during EPS than ejection fraction and infarct size. BZ may be another LGE marker of elevated risk of arrhythmia.
    Cardiology journal 01/2013; 20(1):68-77. · 1.15 Impact Factor
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    ABSTRACT: Background- Implantable cardioverter-defibrillators (ICDs) are increasingly used for primary prevention after randomized, controlled trials demonstrating that they reduce the risk of death in patients with left ventricular systolic dysfunction. The extent to which the clinical characteristics and long-term outcomes of unselected, community-based patients with left ventricular systolic dysfunction undergoing primary prevention ICD implantation in a real-world setting compare with those enrolled in the randomized, controlled trials is not well characterized. This study is being conducted to address these questions. Methods and Results- The study cohort includes consecutive patients undergoing primary prevention ICD placement between January 1, 2006 and December 31, 2009 in 7 health plans. Baseline clinical characteristics were acquired from the National Cardiovascular Data Registry ICD Registry. Longitudinal data collection is underway, and will include hospitalization, mortality, and resource use from standardized health plan data archives. Data regarding ICD therapies will be obtained through chart abstraction and adjudicated by a panel of experts in device therapy. Compared with the populations of primary prevention ICD therapy randomized, controlled trials, the cohort (n=2621) is on average significantly older (by 2.5-6.5 years), more often female, more often from racial and ethnic minority groups, and has a higher burden of coexisting conditions. The cohort is similar, however, to a national population undergoing primary prevention ICD placement. Conclusions- Patients undergoing primary prevention ICD implantation in this study differ from those enrolled in the randomized, controlled trials that established the efficacy of ICDs. Understanding a broad range of health outcomes, including ICD therapies, will provide patients, clinicians, and policy makers with contemporary data to inform decision-making.
    Circulation Cardiovascular Quality and Outcomes 11/2012; 5(6):e78-85. · 5.66 Impact Factor
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    ABSTRACT: BACKGROUND: Implantable cardioverter-defibrillators (ICD) are recommended for the primary prevention of sudden cardiac death in patients with left ventricular dysfunction but it is unclear whether treatment benefits are diminished in patients with very low baseline left ventricular ejection fraction (LVEF) (<25%) or increased in those with prolonged QRS duration (>120 msec). OBJECTIVE: To study the effects of very low LVEF and prolonged QRS duration on the mortality benefits of ICD therapy. METHODS: We performed a meta-analysis of primary prevention randomized controlled trials comparing ICD and standard medical therapy. All-cause mortality hazard ratios in subgroups according to thresholds of 25% for LVEF and 120 msec for QRS duration were extracted from published reports or contributed by trial investigators and synthesized. RESULTS: There was no significant difference of ICD effectiveness in LVEF subgroups of 25-35% (random effects HR 0.81, 95% CI 0.70-0.94) versus <25% (HR 0.71, 95% CI 0.55-0.93). Results were similar also in the narrow and wide QRS subgroups (HR 0.78, 95% CI 0.68-0.90 and 0.70, 0.51-0.95, respectively). Within the LVEF<25% and wide QRS subgroups, there was large heterogeneity driven by the DINAMIT trial that included early post-myocardial infarction patients and its results (HR 1.49, 95% CI 0.84-2.68, and 1.51, 0.83-2.83, respectively) differed significantly from other trials (p=0.008 and p=0.01, respectively). CONCLUSION: LVEF values and QRS duration do not appear to directly modify the survival benefit of ICD in patients with baseline LVEF<35%. However, patients with a recent myocardial infarction do not benefit from ICD, especially when they have LVEF <25% and/or wide QRS.
    Heart rhythm: the official journal of the Heart Rhythm Society 10/2012; · 4.56 Impact Factor
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    ABSTRACT: AIMS: This study investigated autonomic nervous system function in subjects with diabetes during exercise and recovery. METHODS: Eighteen type 2 diabetics (age 55±2years) and twenty healthy controls (age 51±1years) underwent two 16-min bicycle submaximal ECG stress tests followed by 45min of recovery. During session #2, atropine (0.04mg/kg) was administered at peak exercise, and the final two minutes of exercise and entire recovery occurred under parasympathetic blockade. Plasma catecholamines were measured throughout. Parasympathetic effect was defined as the difference between a measured parameter at baseline and after parasympathetic blockade. RESULTS: The parasympathetic effect on the RR interval was blunted (P=.004) in diabetic subjects during recovery. Parasympathetic effect on QT-RR slope during early recovery was diminished in the diabetes group (diabetes 0.13±0.02, control 0.21±0.02, P=.03). Subjects with diabetes had a lower heart rate recovery at 1min (diabetes 18.5±1.9bpm, control 27.6±1.5bpm, P<.001). CONCLUSIONS: In subjects with well-controlled type 2 diabetes, even with minimal evidence of CAN using current methodology, altered cardiac autonomic balance is present and can be detected through an exercise-based assessment for CAN. The early post-exercise recovery period in diabetes was characterized by enhanced sympathoexcitation, diminished parasympathetic reactivation and delay in heart rate recovery.
    Journal of diabetes and its complications 10/2012; · 2.11 Impact Factor
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    ABSTRACT: Background: There is a heightened risk of sudden cardiac death related to exercise and the postexercise recovery period, but the precise mechanism is unknown. We have demonstrated that sympathoexcitation persists for ≥45 minutes after exercise in normals and subjects with coronary artery disease (CAD). The purpose of this study is to determine whether this persistent sympathoexcitation is associated with persistent heart rate variability (HRV) and ventricular repolarization changes in the postexercise recovery period. Methods and Results: Twenty control subjects (age 50.7 ± 1.4 years), 68 subjects (age 58.2 ± 1.5 years) with CAD and preserved left ventricular ejection fraction (LVEF), and 18 subjects (age 57.6 ± 2.4 years) with CAD and depressed LVEF underwent a 16-minute submaximal bicycle exercise protocol with continuous ECG monitoring. QT and RR intervals were measured in recovery to calculate the time dependent corrected QT intervals (QTc), the QT-RR relationship, and HRV. QTc was dependent on the choice of rate correction formula. There were no differences in QT-RR slopes among the three groups in early recovery. HRV recovered quickly in controls, more slowly in those with CAD-preserved LVEF, and to a lesser extent in those with CAD-depressed LVEF. Conclusion: Despite persistent sympathoexcitation for the 45-minute recovery period, ventricular repolarization changes do not persist for that long and HRV changes differ by group. Additional understanding of the dynamic changes in cardiac parameters after exercise is needed to explore the mechanism of increased sudden cardiac death risk at this time.
    Annals of Noninvasive Electrocardiology 10/2012; 17(4):349-60. · 1.08 Impact Factor
  • Heart Rhythm. 09/2012; 9(9):1582–1583.
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    ABSTRACT: Fibrotic and autonomic remodeling in heart failure (HF) increase vulnerability to atrial fibrillation (AF). Because AF electrograms (EGMs) are thought to reflect the underlying structural substrate, we sought to (1) determine the differences in AF EGMs in normal versus HF atria and (2) assess how fibrosis and nerve-rich fat contribute to AF EGM characteristics in HF. AF was induced in 20 normal dogs by vagal stimulation and in 21 HF dogs (subjected to 3 weeks of rapid ventricular pacing at 240 beats per minute). AF EGMs were analyzed for dominant frequency (DF), organization index, fractionation intervals (FIs), and Shannon entropy. In 8 HF dogs, AF EGM correlation with underlying fibrosis/fat/nerves was assessed. In HF compared with normal dogs, DF was lower and organization index/FI/Shannon entropy were greater. DF/FI were more heterogeneous in HF. Percentage fat was greater, and fibrosis and fat were more heterogeneously distributed in the posterior left atrium than in the left atrial appendage. DF/organization index correlated closely with %fibrosis. Heterogeneity of DF/FI correlated with the heterogeneity of fibrosis. Autonomic blockade caused a greater change in DF/FI/Shannon entropy in the posterior left atrium than left atrial appendage, with the decrease in Shannon entropy correlating with %fat. The amount and distribution of fibrosis in the HF atrium seems to contribute to slowing and increased organization of AF EGMs, whereas the nerve-rich fat in the HF posterior left atrium is positively correlated with AF EGM entropy. By allowing for improved detection of regions of dense fibrosis and high autonomic nerve density in the HF atrium, these findings may help enhance the precision and success of substrate-guided ablation for AF.
    Circulation Arrhythmia and Electrophysiology 06/2012; 5(4):640-9. · 5.95 Impact Factor
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    ABSTRACT: Early repolarization (ER) on a 12-lead electrocardiogram has recently been associated with ventricular tachyarrhythmias (VTAs) in patients without structural heart disease and in patients with healed myocardial infarction (MI). An association between ER and VTAs in the setting of acute ST-segment elevation MI (STEMI) has not been explored. In a single-center retrospective case-control design, 50 patients with STEMI complicated by VTAs (cases), defined as ventricular fibrillation, sustained ventricular tachycardia, or nonsustained ventricular tachycardia within 72 hours of the index hospitalization, were matched for age and gender with 50 subjects with STEMI without VTAs (controls). Electrocardiograms obtained an average of 1 year before STEMI were analyzed for ER pattern, defined as notching or slurring of the terminal QRS complex or J-point elevation >0.1 mV above baseline in ≥ 2 contiguous leads. A higher prevalence of ER was associated with VTAs overall in cases compared to controls (26% vs 4%, p = 0.01) and localized to anterior (16% vs 0%) and inferior (14% vs 2%, p = 0.07) leads but not lateral limb leads. Notching (10% vs 2%, p = 0.1) and J-point elevation (16% vs 0%) were more common in cases. Slurring was uncommon. ER was associated with VTAs (odds ratio [OR] 6.5, 95% confidence interval [CI] 1.5 to 28.8, p = 0.01), even after adjustment for creatine kinase-MB (OR 9.2, 95% CI 1.6 to 53.4, p = 0.01) and ejection fraction (OR 5.7, 95% CI 1.2 to 27.1, p = 0.03). In conclusion, ER is associated with VTAs in patients with STEMI even after adjustment for left ventricular ejection fraction or creatine kinas-MB levels. Larger prospective studies exploring potential associations and mechanisms of ventricular arrhythmogenesis with ER pattern are needed.
    The American journal of cardiology 05/2012; 110(5):615-20. · 3.58 Impact Factor
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    ABSTRACT: Baroreflex Response and AF Dominant Frequency. Introduction: Parasympathetic stimulation is known to promote atrial fibrillation (AF) through shortening of atrial refractory periods. We hypothesized that baroreflex-mediated parasympathetic stimulation via phenylephrine (PE) infusion would increase AF rate as measured by dominant frequency (DF). Methods and Results: The protocol was performed in 27 patients (24 M, 59 ± 1 years old) prior to AF ablation. For 10 patients in AF, PE was infused until systolic blood pressure increased ≥30 mmHg. Electrograms were recorded in the left atrium before and after PE. DFs of each recording were calculated offline. Atrial effective refractory periods (ERPs) were measured before and after PE in 11 patients who were in sinus rhythm during the procedure. DFs were also measured in 6 patients in AF before and after complete parasympathetic blockade with atropine (0.04 mg/kg). PE resulted in increased RR intervals during sinus rhythm (1,170 ± 77 to 1,282 ± 85 ms, P = 0.03) and AF (743 ± 32 to 826 ± 30 ms, P = 0.03), consistent with parasympathetic effect on the sinus and AV nodes, respectively. DFs were decreased by PE in the left atrium (6.2 ± 0.2 to 6.0 ± 0.2 Hz, P = 0.004). Correspondingly, atrial ERPs significantly increased from 218 ± 13 to 232 ± 11 ms (P = 0.04). Atropine resulted in a decreasing trend in DF in the left atrium (5.9 ± 0.1 to 5.8 ± 0.1 Hz, P = 0.07). Conclusions: Despite baroreflex-mediated parasympathetic effect, PE produced a slowing of AF along with lengthening of ERP, while parasympathetic blockade also slowed DF. It is therefore likely that the direct and indirect adrenergic effects of PE on atrial electrophysiology are more prominent than its parasympathetic effects. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1045-1050, October 2012).
    Journal of Cardiovascular Electrophysiology 04/2012; 23(10):1045-50. · 3.48 Impact Factor
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    ABSTRACT: Background/Aims Implantable cardioverter defibrillators (ICDs) result in striking mortality benefits among randomized trial populations, but elucidation of outcomes in real-world populations is needed to optimize care and coverage decisions. The Cardiovascular Research Network (CVRN) Longitudinal ICD Study is a new 7-site 3.5-year project evaluating the rate of appropriate device therapies, device complications, hospitalization, mortality, and utilization/cost among a cohort of primary prevention ICD patients. Methods This project links baseline data from the National Cardiovascular Data Registry (NCDR) for ICDs, the virtual data warehouses (VDW) of participating CVRN sites, and novel collection of post-implant ICD device activity from CVRN care delivery systems. NCDR ICD data from 14 implanting hospitals from 2006-2009 were matched to health plan membership and uploaded to the study following necessary approvals. VDW tables have been constructed at the CVRN sites to capture longitudinal clinical and administrative detail. Forms and procedures for abstracting ICD device interrogations and treated arrhythmic episodes have been pilot tested, and procedures have been established both for central review of source documentation and adjudication by an external panel of expert electrophysiologists. Results A cohort of 2500 primary prevention ICD recipients has been assembled. The pilot study evaluated collection and review of device interrogations and treated arrhythmic episodes among a sample of 43 subjects. Lessons from the first study year include: the need to allow additional time and effort to establish/modify contractual agreements between external partners; the benefits of support from an engaged group of stakeholders; the substantial differences across and within study sites as to how ICD device interrogation records are archived and tracked, with local data sources including centralized medical records, stand alone pacemaker/ ICD clinic files, electronic interrogation archives, and remote interrogation websites; and, the importance of caution when planning for the review and adjudication of real world medical record data based on published approaches from prospective trials. Conclusions Following establishment of the study cohort and piloting abstraction/adjudication procedures, the data collection phase is underway. Further lessons from initial abstraction will be available at the time of the HMORN conference. The study period ends March 2013.
    Clinical Medicine &amp Research 11/2011; 9(3-4):151.
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    ABSTRACT: Multiple formats have been used to deliver information needed for informed consent before a medical procedure, but data comparing formats are conflicting. Sixty-three patients (45 men, age 61 ± 16 years) undergoing an initial diagnostic cardiac electrophysiology study were randomly assigned to 1 of 3 groups: oral, written, or video informed consent using a standardized text for all 3 formats. Anxiety levels were assessed with the Spielberger State-Trait Anxiety Inventory (STAI), and questionnaires were used to assess patient comprehension and satisfaction with the informed consent process. Physician time needed to obtain informed consent was also measured. The effect of informed consent format on anxiety state was evaluated by comparing STAI before and after consent. Multivariable analysis was performed to assess the effects of baseline characteristics on the state anxiety scores. For the oral, written, and video formats, the mean anxiety trait scores were 39 ± 9, 34 ± 8, and 31 ± 7, respectively (P = .005), and baseline anxiety state scores were 49 ± 12, 37 ± 12, and 36 ± 11, respectively (P = .0006). None of the formats had a significant effect on patient anxiety state after consent was obtained. After the procedure, anxiety state declined (P < .0001). There were no differences among the comprehension scores, and patient satisfaction was equivalent among formats. The oral format required the longest physician time (P = .06). For electrophysiologic testing, all 3 formats have similar effects on anxiety and produce equivalent patient comprehension. The oral format requires more physician time. Given the standardization achievable with a written or video format, physicians may consider these options to facilitate obtaining informed consent.
    American heart journal 10/2011; 162(4):780-785.e1. · 4.65 Impact Factor

Publication Stats

6k Citations
2,025.60 Total Impact Points


  • 1992–2014
    • Northwestern University
      • • Division of Hospital Medicine
      • • Bluhm Cardiovascular Institute
      • • Division of Cardiology (Dept. of Medicine)
      • • Feinberg School of Medicine
      • • Cardiac Electrophysiology Unit
      • • Feinberg Cardiovascular Research Institute
      • • Department of Medicine
      • • Division of General Internal Medicine and Geriatrics
      Evanston, Illinois, United States
  • 2013
    • Duke University
      Durham, North Carolina, United States
    • University of Auckland
      • Department of Anatomy with Radiology
      Auckland, Auckland, New Zealand
  • 1991–2012
    • Northwestern Memorial Hospital
      Chicago, Illinois, United States
    • University of California, San Francisco
      • Division of Hospital Medicine
      San Francisco, CA, United States
  • 2011
    • University of California, Los Angeles
      Los Angeles, California, United States
  • 2008–2011
    • The Ohio State University
      • Division of Cardiovascular Medicine
      Columbus, Ohio, United States
    • Thomas Jefferson University
      • Division of Hospital Medicine
      Philadelphia, PA, United States
    • Beijing Fuwai Hospital
      Peping, Beijing, China
    • Partners HealthCare
      Boston, Massachusetts, United States
    • American Heart Association
      Dallas, Texas, United States
  • 1992–2011
    • University of Illinois at Chicago
      • Section of Cardiology
      Chicago, Illinois, United States
  • 2010
    • Medical College of Wisconsin
      • Division of Cardiology
      Milwaukee, WI, United States
    • Orlando VA Medical Center
      Orlando, Florida, United States
  • 1988–2010
    • Johns Hopkins Medicine
      • Department of Medicine
      Baltimore, Maryland, United States
  • 2009
    • Columbia University
      • Division of Cardiology
      New York City, NY, United States
    • University Center Rochester
      • Department of Medicine
      Rochester, Minnesota, United States
  • 2007
    • Mayo Clinic - Rochester
      Rochester, Minnesota, United States
  • 2006
    • University of Maryland, Baltimore
      • Division of Cardiology
      Baltimore, MD, United States
    • Richmond VA Medical Center
      Richmond, Virginia, United States
  • 1993
    • Children's Memorial Hospital
      Chicago, Illinois, United States
  • 1989–1993
    • University of Michigan
      • • Department of Internal Medicine
      • • Department of Electrical Engineering and Computer Science (EECS)
      Ann Arbor, MI, United States
  • 1988–1993
    • Concordia University–Ann Arbor
      Ann Arbor, Michigan, United States
  • 1989–1990
    • St. Francis Hospital
      Roslyn, New York, United States
  • 1988–1990
    • University of Pennsylvania
      • Department of Animal Biology
      Philadelphia, PA, United States
  • 1987–1989
    • Hospital of the University of Pennsylvania
      • Department of Medicine
      Philadelphia, Pennsylvania, United States
    • Johns Hopkins University
      Baltimore, Maryland, United States