Cardiovascular System Commons^™

Rapid Door To Balloon Time In The Treatment Of Acute St- Elevation Myocardial Infarction Meaningfully Reduces Overall Hospital Stay, Amit N. Nanavati Md, Nainesh Patel Md, Bruce Feldman Do, J Patrick Kleaveland Md, Orlando E. Rivera Rn, David A. Cox Md

Department of Medicine

No abstract provided.

Factors Affecting Growth In Infants With Single Ventricle Physiology: A Report From The Pediatric Heart Network Infant Single Ventricle Trial., Richard V. Williams, Victor Zak, Chitra Ravishankar, Karen Altmann, Jeffrey Anderson, Andrew M. Atz, Carolyn Dunbar-Masterson, Nancy Ghanayem, Linda Lambert, Karen Lurito, Barbara Medoff-Cooper, Renee Margossian, Victoria L. Pemberton, Jennifer Russell, Mario Stylianou, Daphne Hsu, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

OBJECTIVES: To describe growth patterns in infants with single ventricle physiology and determine factors influencing growth.

STUDY DESIGN: Data from 230 subjects enrolled in the Pediatric Heart Network Infant Single Ventricle Enalapril Trial were used to assess factors influencing change in weight-for-age z-score (z) from study enrollment (0.7 ± 0.4 months) to pre-superior cavopulmonary connection (SCPC; 5.1 ± 1.8 months, period 1) and pre-SCPC to final study visit (14.1 ± 0.9 months, period 2). Predictor variables included patient characteristics, feeding regimen, clinical center, and medical factors during neonatal (period 1) and SCPC hospitalizations (period 2). Univariate regression analysis was performed, …

Non-Geometric Echocardiographic Indices Of Ventricular Function In Patients With A Fontan Circulation., Jonathan Rhodes, Renee Margossian, Lynn A. Sleeper, Piers Barker, Timothy J. Bradley, Minmin Lu, Mark Fogel, Matthew A. Harris, Wyman W. Lai, Andrew J. Powell, Michael D. Puchalski, Girish S. Shirali, Steven D. Colan, Pediatric Heart Network Investigators

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Complex anatomy and limited windows complicate echocardiographic assessments of ventricular function in Fontan patients. For the Pediatric Heart Network Fontan Cross-Sectional Study, data were acquired from which mean ventricular pressure change during isovolumetric contraction (dP/dt(ic)), Tei index, and maximal systolic annular velocity (S') could be measured. The purpose of this study was to compare these nongeometric indices of ventricular function to cardiac magnetic resonance (CMR) measurements of ventricular ejection fraction (EF).

METHODS: Echocardiographic and CMR studies were performed prospectively using standardized protocols; measurements were completed by core laboratories. Data from both modalities were available from 137 patients.

RESULTS: A …

Left Ventricular Assist Devices: Engineering Design Considerations, Marwan A. Simaan, Eduardo Divo, George Faragallah, Yu Wang

Publications

Patients with end-stage congestive heart failure awaiting heart transplantation often wait long periods of time (300 days or more on the average) before a suitable donor heart becomes available. The medical community has placed increased emphasis on the use of Left Ventricular Assist Devices or LVADs that can substitute for, or enhance, the function of the natural heart while the patient is waiting for the heart transplant (Poirier, 1997; Frazier & Myers, 1999). Essentially, a rotary LVAD is a pump that operates continuously directing blood from the left ventricle into the aorta by avoiding the aortic valve. Generally speaking, the …

Factors Associated With Serum Brain Natriuretic Peptide Levels After The Fontan Procedure., Andrew M. Atz, Victor Zak, Roger E. Breitbart, Steven D. Colan, Sara K. Pasquali, Daphne T. Hsu, Minmin Lu, Lynn Mahony, Stephen M. Paridon, Michael D. Puchalski, Tal Geva, Brian W. Mccrindle, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

OBJECTIVE: Although a useful marker of heart failure in adults, the utility of brain natriuretic peptide concentration (BNP) for children after the Fontan procedure is not well studied.

DESIGN: BNP was measured in 510 patients who were 6-18 years old in the Pediatric Heart Network Fontan cross-sectional study at a median of 8.2 years after Fontan. Patients underwent echocardiography, exercise testing, magnetic resonance imaging (MRI) and functional health status questionnaires. Associations of BNP with baseline patient characteristics, medical history and cross-sectional assessment were examined with multivariable linear regression analyses.

RESULTS: The distribution of BNP was highly skewed, median 13.0 pg/mL …

Surgical Management Of Complete Atrioventricular Septal Defect: Associations With Surgical Technique, Age, And Trisomy 21., Andrew M. Atz, John A. Hawkins, Minmin Lu, Meryl S. Cohen, Steven D. Colan, James Jaggers, Ronald V. Lacro, Brian W. Mccrindle, Renee Margossian, Ralph S. Mosca, Lynn A. Sleeper, L Luann Minich, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

OBJECTIVES: We sought to evaluate the contemporary results after repair of a complete atrioventricular septal defect and to determine the factors associated with suboptimal outcomes.

METHODS: The demographic, procedural, and outcome data were obtained within 1 and 6 months after repair of a complete atrioventricular septal defect in 120 children in a multicenter observational study from June 2004 to 2006.

RESULTS: The median age at surgery was 3.7 months (range, 9 days to 1.1 years). The type of surgical repair was a single patch (18%), double patch (72%), and a single atrial septal defect patch with primary ventricular septal defect …

Ischemia Impairs Vasodilation In Skeletal Muscle Resistance Artery, Kyle Remington Struthers

Master's Theses

Functional vasodilation in arterioles is impaired with chronic ischemia. We sought to examine the impact of chronic ischemia and age on skeletal muscle resistance artery function. To examine the impact of chronic ischemia, the femoral artery was resected from young (2-3mo) and adult (6-7mo) mice and the profunda femoris artery diameter was measured at rest and following gracilis muscle contraction 14 days later using intravital microscopy. Functional vasodilation was significantly impaired in ischemic mice (14.4±4.6% vs. 137.8±14.3%, p<0.0001 n=8) and non-ischemic adult mice (103.0±9.4% vs. 137.8±14.3%, p=0.05 n=10). In order to analyze the cellular mechanisms of the impairment, a protocol was developed to apply pharmacological agents to the experimental preparation while maintaining tissue homeostasis. Endothelial and smooth muscle dependent vasodilation were impaired with ischemia, 39.6 ± 13.6% vs. 80.5 ± 11.4% and 43.0 ± 11.7% vs. 85.1 ± 10.5%, respectively. From this data, it can be supported that smooth muscle dysfunction is the reason for the observed impairment in arterial vasodilation.

Renin-Angiotensin-Aldosterone Genotype Influences Ventricular Remodeling In Infants With Single Ventricle., Seema Mital, Wendy K. Chung, Steven D. Colan, Lynn A. Sleeper, Cedric Manlhiot, Cammon B. Arrington, James F. Cnota, Eric M. Graham, Michael E. Mitchell, Elizabeth Goldmuntz, Jennifer S. Li, Jami C. Levine, Teresa M. Lee, Renee Margossian, Daphne T. Hsu, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

Background: We investigated the effect of polymorphisms in the renin-angiotensin-aldosterone system (RAAS) genes on ventricular remodeling, growth, renal function, and response to enalapril in infants with single ventricle.

Methods and results: Single ventricle infants enrolled in a randomized trial of enalapril were genotyped for polymorphisms in 5 genes: angiotensinogen, angiotensin-converting enzyme, angiotensin II type 1 receptor, aldosterone synthase, and chymase. Alleles associated with renin-angiotensin-aldosterone system upregulation were classified as risk alleles. Ventricular mass, volume, somatic growth, renal function using estimated glomerular filtration rate, and response to enalapril were compared between patients with ≥2 homozygous risk genotypes (high risk), and those …

Is There A Benefit To Screening For Abdominal Aortic Aneurysm In The Irish Male Population Between The Ages Of 55 To 75 Years; An Ideal Opportunity Group For Evaluating Cardiovascular Risk Factors?, Mairead Brosnan

Masters

Introduction: Abdominal Aortic Aneurysm (AAA) screening programmes have been carried out worldwide on males between the ages of 65-75 years. The results of such programmes show AAA screening to be beneficial and cost effective. In the Multicentre Aneurysm Screening Study conducted in the United Kingdom, the incidence of AAA was 4.9%. Early diagnoses of AAA’s have reduced AAA related deaths by 42%. This study investigated the incidence of AAA in Irish males between the ages of 55-75 years and incorporated an assessment of cardiovascular risk factors. A younger group of males were screened to see if there was any benefit …

The Mechanosensory Role Of Primary Cilia In Vascular Hypertension, Surya M. Nauli, Xingjian Jin, Beerend P. Hierck

Pharmacy Faculty Articles and Research

Local regulation of vascular tone plays an important role in cardiovascular control of blood pressure. Aside from chemical or hormonal regulations, this local homeostasis is highly regulated by fluid-shear stress. It was previously unclear how vascular endothelial cells were able to sense fluid-shear stress. The cellular functions of mechanosensory cilia within vascular system have emerged recently. In particular, hypertension is insidious and remains a continuous problem that evolves during the course of polycystic kidney disease (PKD). The basic and clinical perspectives on primary cilia are discussed with regard to the pathogenesis of hypertension in PKD.

Cardiac Jelly And Its Roles In Heart Development, Sara Zucker

The Science Journal of the Lander College of Arts and Sciences

The following is the introduction to this article: The complexity of the developing and functioning heart has always intrigued scientists. One of the many ambiguous areas in the understanding of cardiac development is the role of a gelatinous substance commonly referred to as cardiac jelly, (Davis, 1924) and more recently the myocardial basement membrane (Little and Rongish, 1995). Researchers have been studying this material to determine its roles. Their studies led them to believe that this jelly-like substance may be involved in vital embryological roles including the actual morphogenesis of the heart, such as heart valve formation and pumping. When …

The Role Of Endothelial Nitric Oxide Synthase (Enos) Uncoupling On Leukocyte-Endothelial Interactions In Rat Mesenteric Postcapillary Venules, Maria Kern

PCOM Biomedical Studies Student Scholarship

Endothelial derived nitric oxide (NO) is essential in the regulation of blood pressure and attenuates leukocyte-endothelial interactions associated with vascular injury. However, when endothelial-derived NO is decreased, endothelial dysfunction results and promotes inflammation characterized by increased leukocyte-endothelial interactions. Under normal conditions, eNOS produces NO in the presence of an essential cofactor, tetrahydrobiopetrin (BH4) by facilitating the reduction of molecular oxygen to L-arginine oxidation and generation of L-citrulline. Whereas uncoupled eNOS refers to the electron transfer that becomes uncoupled to L-arginine oxidation and therefore superoxide (SO) is generated when the dihydrobiopetrin (BH2) to BH4 ratio is increased. SO is subsequently converted …

The Effects Of Protein Kinase C Inhibitors On Blood Nitric Oxide And Hydrogen Peroxide Release In Ischemia And Reperfusion Injury, Kyle D. Bartol

PCOM Biomedical Studies Student Scholarship

Vascular endothelial dysfunction is a key component initiating oxidative stress in ischemia/reperfusion (I/R). Endothelial dysfunction is characterized by an increase in hydrogen peroxide (H2O2) and a decrease in the bioavailability of nitric oxide (NO). Previous studies using protein kinase C (PKC) inhibitor Gö 6983 or PKC Beta (β) II inhibitor improved cardiac function in myocardial I/R, decreased leukocyte-endothelial interactions and leukocyte superoxide (SO) release and increased endothelial-derived NO release in vitro. This study examined the effects of Gö 6983 or PKC β II inhibitor on realtime H2O2 and NO release in femoral vein I/R in vivo. NO or H2O2 microsensors …

Relation Of Size Of Secondary Ventricles To Exercise Performance In Children After Fontan Operation., Ashwin Prakash, Thomas G. Travison, Mark A. Fogel, Lynne M. Hurwitz, Andrew J. Powell, Beth F. Printz, Michael D. Puchalski, Girish S. Shirali, Shi-Joon Yoo, Tal Geva, Pediatric Heart Network Investigators

Manuscripts, Articles, Book Chapters and Other Papers

The effects of the nondominant or secondary ventricle on the Fontan circulation are not known. The present study used cardiac magnetic resonance imaging to investigate the relations between secondary ventricular size and global cardiac performance. The Fontan cross-sectional study collected data from 7 centers participating in the Pediatric Heart Network. Subjects with complete cardiac magnetic resonance imaging data and an identifiable secondary ventricle were included in the analysis. Relationships between body surface area-adjusted parameters of the secondary ventricle (mass, end-diastolic volume, mass/volume ratio, and stroke volume) and the following measures were assessed. These measures included the percentage of predicted peak …

Mitochondrial Regulation Of Arterial Contractility, Damodaran Narayanan

Theses and Dissertations (ETD)

Rationale: Physiological functions of mitochondria in contractile arterial smooth muscle cells are poorly understood. Mitochondria can uptake calcium (Ca²⁺), but intracellular Ca²⁺ signals that regulate mitochondrial Ca²⁺ concentration ([Ca²⁺]_mito) and physiological functions of changes in [Ca²⁺]_mito in arterial smooth muscle cells are unclear.

Objective: Identify Ca²⁺ signals that regulate [Ca²⁺]_mito, examine the significance of changes in [Ca²⁺]_mito, and test the hypothesis that [Ca²⁺]_mito controls functional ion channel transcription in smooth muscle cells of resistance–size cerebral arteries.

Methods …

Prenatal Diagnosis And Risk Factors For Preoperative Death In Neonates With Single Right Ventricle And Systemic Outflow Obstruction: Screening Data From The Pediatric Heart Network Single Ventricle Reconstruction Trial(∗)., Andrew M. Atz, Thomas G. Travison, Ismee A. Williams, Gail D. Pearson, Peter C. Laussen, William T. Mahle, Amanda L. Cook, Joel A. Kirsh, Mark Sklansky, Svetlana Khaikin, Caren Goldberg, Michele Frommelt, Catherine Krawczeski, Michael D. Puchalski, Jeffrey P. Jacobs, Jeanne M. Baffa, Jack Rychik, Richard G. Ohye, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

OBJECTIVES: The purpose of this analysis was to assess preoperative risk factors before the first-stage Norwood procedure in infants with hypoplastic left heart syndrome and related single-ventricle lesions and to evaluate practice patterns in prenatal diagnosis, as well as the role of prenatal diagnosis in outcome.

METHODS: Data from all live births with morphologic single right ventricle and systemic outflow obstruction screened for the Pediatric Heart Network's Single Ventricle Reconstruction Trial were used to investigate prenatal diagnosis and preoperative risk factors. Demographics, gestational age, prenatal diagnosis status, presence of major extracardiac congenital abnormalities, and preoperative mortality rates were recorded.

RESULTS: …

Enalapril In Infants With Single Ventricle: Results Of A Multicenter Randomized Trial., Daphne T. Hsu, Victor Zak, Lynn Mahony, Lynn A. Sleeper, Andrew M. Atz, Jami C. Levine, Piers C. Barker, Chitra Ravishankar, Brian W. Mccrindle, Richard V. Williams, Karen Altmann, Nancy S. Ghanayem, Renee Margossian, Wendy K. Chung, William L. Border, Gail D. Pearson, Mario P. Stylianou, Seema Mital, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Angiotensin-converting enzyme inhibitor therapy improves clinical outcome and ventricular function in adults with heart failure. Infants with single-ventricle physiology have poor growth and are at risk for abnormalities in ventricular systolic and diastolic function. The ability of angiotensin-converting enzyme inhibitor therapy to preserve ventricular function and improve somatic growth and outcomes in these infants is unknown.

METHODS AND RESULTS: The Pediatric Heart Network conducted a double-blind trial involving 230 infants with single-ventricle physiology randomized to receive enalapril (target dose 0.4 mg . kg(-1) . d(-1)) or placebo who were followed up until 14 months of age. The primary end …

Hypoxia And Fetal Programming Of Cardiovascular Dysfunction, Qin Xue

Loma Linda University Electronic Theses, Dissertations & Projects

Human epidemiological studies have shown a clear association of adverse intrauterine environment and an increased risk of ischemic heart disease in later adult life. Of all the stresses to which the fetus is subjected, perhaps the most important and clinically relevant is that of hypoxia. The goal of this project is to test the hypothesis that chronic hypoxia during gestation adversely affects fetal cardiovascular development and impairs cardiac function in offspring. In the first part of project, we tested the hypothesis that chronic hypoxia adversely regulates contractility of fetal pulmonary arteries and veins in sheep residing at high altitude (3,801 …

Fetal Programming By Nicotine Increases Cardiac Susceptibility To Ischemic Injury, Jennifer Charlotte Alexie Lawrence

Loma Linda University Electronic Theses, Dissertations & Projects

Fetal programming is the area of study that focuses on the prenatal origins of adult onset disorders. Previous studies have associated an adverse prenatal environment with the onset of physiologic and metabolic diseases during adulthood. Fetal malnutrition, hypoxia, and exposure to drugs - such as cocaine and nicotine - have been associated with adult disease states. Cigarette smoking is the number one cause of preventable death in the developed world. Among the many dangerous chemicals found in tobacco products is nicotine, the compound responsible for the addictive nature of tobacco use. Nicotine use during pregnancy is a known cause of …

Initial Experience With A Miniaturized Multiplane Transesophageal Probe In Small Infants Undergoing Cardiac Operations., Sinai C. Zyblewski, Girish S. Shirali, Geoffrey A. Forbus, Tain-Yen Hsia, Scott M. Bradley, Andrew M. Atz, Meryl S. Cohen, Eric M. Graham

Manuscripts, Articles, Book Chapters and Other Papers

PURPOSE: There has been reluctance to use intraoperative transesophageal echocardiography (TEE) in small infants. We assessed the utility and safety of a new miniaturized multiplane micro-TEE probe in small infants undergoing cardiac operations.

DESCRIPTION: Hemodynamic and ventilation variables were prospectively recorded before and after micro-TEE insertion and removal in infants weighing 5 kg or less undergoing cardiac operations.

EVALUATION: The study included 42 patients with a mean weight of 3.6 +/- 0.9 kg (range, 1.7 to 5 kg). All probe insertions were successful. There were no complications or clinically significant changes in hemodynamic or ventilation variables. Information provided by TEE …