Medicine and Health Sciences Commons^™

Device Therapies Among Patients Receiving Primary Prevention Implantable Cardioverter-Defibrillators In The Cardiovascular Research Network, Robert T. Greenlee, Alan S. Go, Pamela N. Peterson, Andrea E. Cassidy-Bushrow, Charles Gaber, Romel Garcia-Montilla, Alan H. Kadish

Office of the President Publications and Research

BACKGROUND: Primary prevention implantable cardioverter-defibrillators (ICDs) reduce mortality in selected patients with left ventricular systolic dysfunction by delivering therapies (antitachycardia pacing or shocks) to terminate potentially lethal arrhythmias; inappropriate therapies also occur. We assessed device therapies among adults receiving primary prevention ICDs in 7 healthcare systems.

METHODS AND RESULTS: We linked medical record data, adjudicated device therapies, and the National Cardiovascular Data Registry ICD Registry. Survival analysis evaluated therapy probability and predictors after ICD implant from 2006 to 2009, with attention to Centers for Medicare and Medicaid Services Coverage With Evidence Development subgroups: left ventricular ejection fraction, 31% to 35%; …

Outer Limits Of Biotechnologies: A Jewish Perspective, John D. Loike, Alan H. Kadish

Office of the President Publications and Research

A great deal of biomedical research focuses on new biotechnologies such as gene editing, stem cell biology and reproductive medicine, which have created a scientific revolution. While the potential medical benefits of this research may be far-reaching, ethical issues related to non-medical applications of these technologies are demanding. We analyze, from a Jewish legal perspective, some of the ethical conundrums that society faces in pushing the outer limits in researching these new biotechnologies.

Orthogonal Decomposition Of Left Ventricular Remodeling In Myocardial Infarction, Xingyu Zhang, Pau Medrano-Gracia, Bharath Ambale-Venkatesh, David A. Bluemke, Brett R. Cowan, J. Paul Finn, Alan H. Kadish

Office of the President Publications and Research

BACKGROUND: Left ventricular size and shape are important for quantifying cardiac remodeling in response to cardiovascular disease. Geometric remodeling indices have been shown to have prognostic value in predicting adverse events in the clinical literature, but these often describe interrelated shape changes. We developed a novel method for deriving orthogonal remodeling components directly from any (moderately independent) set of clinical remodeling indices.

RESULTS: Six clinical remodeling indices (end-diastolic volume index, sphericity, relative wall thickness, ejection fraction, apical conicity, and longitudinal shortening) were evaluated using cardiac magnetic resonance images of 300 patients with myocardial infarction, and 1991 asymptomatic subjects, obtained from …

Comparison Of Inappropriate Shocks And Other Health Outcomes Between Single- And Dual-Chamber Implantable Cardioverter-Defibrillators For Primary Prevention Of Sudden Cardiac Death: Results From The Cardiovascular Research Network Longitudinal Study Of Implantable Cardioverter-Defibrillators, Pamela N. Peterson, Robert T. Greenlee, Alan S. Go, David J. Magid, Andrea Cassidy-Bushrow, Romel Garcia-Montilla, Alan H. Kadish

Office of the President Publications and Research

Background In US clinical practice, many patients who undergo placement of an implantable cardioverter‐defibrillator (ICD) for primary prevention of sudden cardiac death receive dual‐chamber devices. The superiority of dual‐chamber over single‐chamber devices in reducing the risk of inappropriate ICD shocks in clinical practice has not been established. The objective of this study was to compare risk of adverse outcomes, including inappropriate shocks, between single‐ and dual‐chamber ICDs for primary prevention.

Methods and Results We identified patients receiving a single‐ or dual‐chamber ICD for primary prevention who did not have an indication for pacing from 15 hospitals within 7 integrated health …

Information Maximizing Component Analysis Of Left Ventricular Remodeling Due To Myocardial Infarction, Xingyu Zhang, Bharath Ambale-Venkatesh, David A. Bluemke, Brett R. Cowan, J. Paul Finn, Alan H. Kadish, Pau Medrano-Gracia

Office of the President Publications and Research

Background: Although adverse left ventricular shape changes (remodeling) after myocardial infarction (MI) are predictive of morbidity and mortality, current clinical assessment is limited to simple mass and volume measures, or dimension ratios such as length to width ratio. We hypothesized that information maximizing component analysis (IMCA), a supervised feature extraction method, can provide more efficient and sensitive indices of overall remodeling.

Methods: IMCA was compared to linear discriminant analysis (LDA), both supervised methods, to extract the most discriminatory global shape changes associated with remodeling after MI. Finite element shape models from 300 patients with myocardial infarction from the …

Atlas-Based Quantification Of Cardiac Remodeling Due To Myocardial Infarction, Xingyu Zhang, Brett R. Cowan, David A. Bluemke, J. Paul Finn, Carissa G. Fonseca, Alan H. Kadish, Pau Medrano-Gracia

Office of the President Publications and Research

Myocardial infarction leads to changes in the geometry (remodeling) of the left ventricle (LV) of the heart. The degree and type of remodeling provides important diagnostic information for the therapeutic management of ischemic heart disease. In this paper, we present a novel analysis framework for characterizing remodeling after myocardial infarction, using LV shape descriptors derived from atlas-based shape models. Cardiac magnetic resonance images from 300 patients with myocardial infarction and 1991 asymptomatic volunteers were obtained from the Cardiac Atlas Project. Finite element models were customized to the spatio-temporal shape and function of each case using guide-point modeling. Principal component analysis …

Cardiac Troponin Assessment Following Atrial Fibrillation Ablation: Implications For Chest Pain Evaluation, Jason C. Rubenstein, Jason T. Jacobson, Jeffrey J. Goldberger, Rod Passman, Alan H. Kadish, Michael H. Kim

Office of the President Publications and Research

Background: The range of elevation of troponin I (tI) that is within expected limits from left atrial radiofrequency ablation for atrial fibrillation (AF) is not well described, though such information may be of clinical value.

Objectives: Identify the expected range of tI values post-atrial fibrillation (AF) ablation.

Methods: 31 patients undergoing AF ablation had a single tI level drawn the day following the procedure. Clinical variables were also collected, such as ablation type and radiofrequency (RF) time.

Results: Paroxysmal AF was present in 23 patients, and 8 had chronic AF. The average RF time was 2627.8 …

Atlas-Based Analysis Of Cardiac Shape And Function: Correction Of Regional Shape Bias Due To Imaging Protocol For Population Studies, Pau Medrano-Gracia, Brett R. Cowan, David A. Bluemke, J. Paul Finn, Alan H. Kadish, Daniel C. Lee, Alistair A. Young

Office of the President Publications and Research

Background: 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.

Methods: 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 …

The Cardiac Atlas Project--An Imaging Database For Computational Modeling And Statistical Atlases Of The Heart, Carissa G. Fonseca, Michael Backhaus, David A. Bluemke, Randall D. Britten, Jae Do Chung, Brett R. Cowan, Alan H. Kadish

Office of the President Publications and Research

MOTIVATION: Integrative mathematical and statistical models of cardiac anatomy and physiology can play a vital role in understanding cardiac disease phenotype and planning therapeutic strategies. However, the accuracy and predictive power of such models is dependent upon the breadth and depth of noninvasive imaging datasets. The Cardiac Atlas Project (CAP) has established a large-scale database of cardiac imaging examinations and associated clinical data in order to develop a shareable, web-accessible, structural and functional atlas of the normal and pathological heart for clinical, research and educational purposes. A goal of CAP is to facilitate collaborative statistical analysis of regional heart shape …

Prophylactic Defibrillator Implantation—Toward An Evidence-Based Approach, Alan H. Kadish

Office of the President Publications and Research

The author discusses research on using implantable cardioverter-defibrillators for the primary prevention of sudden death.

Implantable Cardioverter–Defibrillators: Reply, Alan H. Kadish

Office of the President Publications and Research

The author replies to comments on a previously published article discussing implantable cardioverter-defibrillators.

Prophylactic Defibrillator Implantation In Patients With Nonischemic Dilated Cardiomyopathy, Alan H. Kadish, Alan Dyer, James P. Daubert, Rebecca Quigg, N. A. Mark Estes, Kelley P. Anderson, Joseph H. Levine

Office of the President Publications and Research

No abstract provided.