Cardiology Commons^™

Management Of Acute Regurgitation In Left-Sided Cardiac Valves, Nahush A Mokadam, Karen K Stout, Edward D Verrier

The Texas Heart Institute Journal

The management of acute, severe cardiac valvular regurgitation requires expeditious multidisciplinary care. Although acute, severe valvular regurgitation can be a true surgical emergency, accurate diagnosis and subsequent treatment decisions require clinical acumen, appropriate imaging, and sound judgment. An accurate and timely diagnosis is essential for successful outcomes and requires appropriate expertise and a sufficiently high degree of suspicion in a variety of settings. Whereas cardiovascular collapse is the most obvious and common presentation of acute cardiac valvular regurgitation, findings may be subtle, and the clinical presentation can often be nonspecific. Consequently, other acute conditions such as sepsis, pneumonia, or nonvalvular …

Cardiac Surgery: A Century Of Progress, Allen B Weisse

The Texas Heart Institute Journal

Well into the first decades of the 20th century, medical opinion held that any surgical attempts to treat heart disease were not only misguided, but unethical. Despite such reservations, innovative surgeons showed that heart wounds could be successfully repaired. Then, extracardiac procedures were performed to correct patent ductus arteriosus, coarctation of the aorta, and tetralogy of Fallot. Direct surgery on the heart was accomplished with closed commissurotomy for mitral stenosis. The introduction of the heart-lung machine and cardiopulmonary bypass enabled the surgical treatment of other congenital and acquired heart diseases. Advances in aortic surgery paralleled these successes. The development of …

Left Atrial Ablation For Atrial Fibrillation: Creating The “Box Lesion” With A Bipolar Radiofrequency Device, Leonid Sternik, Hartzel V Schaff, David Luria, Michael Glikson, Alexander Kogan, Ateret Malachy, Maya First, Ehud Raanani

The Texas Heart Institute Journal

The maze procedure is the gold standard for the ablation of atrial fibrillation, and the “box lesion” around the pulmonary veins is the most important part of this procedure. We have created this lesion with a bipolar radiofrequency ablator, abandoning the usual use of this device (to achieve bilateral epicardial isolation of the pulmonary veins).

From March 2004 through the end of May 2010, we performed surgical ablation of atrial fibrillation in 240 patients. Of this number, 205 underwent operation by a hybrid maze technique and the remaining 35 (our study cohort) underwent the creation of a box lesion around …

Rosuvastatin Therapy Does Not Affect Serum Mmp-13 Or Timp-1 Levels In Hypercholesterolemic Patients, Cihan Cevik, Kenneth Nugent, Gary Meyerrose, Mohammad Otahbachi, Cemil Izgi, Mark Lyte, R David Fish

The Texas Heart Institute Journal

Matrix metalloproteinases degrade the collagen content of atherosclerotic plaque and reduce plaque stability. In tissue sections of atherosclerotic plaque, the expression of matrix metalloproteinases is increased. 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) decrease the tissue expression of matrix metalloproteinases-1, -2, -3, and -9 in atheromatous plaque by attenuating the inflammatory process that leads to increased expression. However, it is not known whether statins decrease levels of matrix metalloproteinase-13—an enzyme crucial to the initiation of collagen degradation—as part of their plaque-stabilizing effect.

We prospectively examined the effect of statin therapy on serum levels of matrix metalloproteinase-13, tissue inhibitor of metalloproteinase-1, and …

Sirolimus-Eluting Stents Versus Bare-Metal Stents In Routine Clinical Use, Muhammad Munir, Jonathan Aliota, Amany Ahmed, Anwarullah Mohammed, Vei Vei Lee, Macarthur A Elayda, James M Wilson

The Texas Heart Institute Journal

Conflicting patient outcomes have been reported after the use of sirolimus-eluting stents or bare-metal stents. In this nonrandomized study, we examine the outcomes after placement of sirolimus-eluting versus bare-metal stents in an unselected population of patients who underwent percutaneous coronary revascularization.

We used THIRD-base, a longitudinal data registry of patients who underwent revascularization at our institution, to compare demographics and outcomes in patients treated with a sirolimus-eluting or bare-metal stent from January 2001 through June 2006. Outcome measures included major acute coronary and cerebral events at 30 days, target-vessel failure at 9 months and at 3 years, and stent thrombosis. …

Robotic Cardiac Surgery By 2031, W Randolph Chitwood

The Texas Heart Institute Journal

No abstract provided.

Prehypertension: A Meta-Analysis Of The Epidemiology, Risk Factors, And Predictors Of Progression, Xiaofan Guo, Liling Zou, Xingang Zhang, Jue Li, Liqiang Zheng, Zhaoqing Sun, Jian Hu, Nathan D Wong, Yingxian Sun

The Texas Heart Institute Journal

We investigated the prevalence and risk factors of prehypertension, as well as the predictors of progression from prehypertension to hypertension. To do this, we performed a systematic review and meta-analysis of cross-sectional and longitudinal studies, after unrestricted searches of PubMed and The Cochrane Library through September 2010. In addition, we reviewed references, major textbooks, and review articles. Pooled prevalence, standardized mean differences, and odds ratios were estimated by using a random-effects model.

Twenty-six articles met our inclusion criteria; these included 20 cross-sectional and 6 longitudinal studies, with a total sample of 250,741 individuals. The overall pooled prevalence of prehypertension was …

Central Venous Pressure And Pulmonary Capillary Wedge Pressure, Tony S Ma, Biykem Bozkurt, David Paniagua, Biswajit Kar, Kumudha Ramasubbu, Carl F Rothe

The Texas Heart Institute Journal

Heart-failure phenotypes include pulmonary and systemic venous congestion. Traditional heart-failure classification systems include the Forrester hemodynamic subsets, which use 2 indices: pulmonary capillary wedge pressure (PCWP) and cardiac index. We hypothesized that changes in PCWP and central venous pressure (CVP), and in the phenotypes of heart failure, might be better evaluated by cardiovascular modeling. Therefore, we developed a lumped-parameter cardiovascular model and analyzed forms of heart failure in which the right and left ventricles failed disproportionately (discordant ventricular failure) versus equally (concordant failure). At least 10 modeling analyses were carried out to the equilibrium state. Acute discordant pump failure was …

Reflections On A Heart Surgery Career With Insights For Western-Trained Medical Specialists In Developing Countries, Sami S Kabbani

The Texas Heart Institute Journal

Herein, I describe my experience (spanning 40 years) in helping to develop the specialty of cardiovascular surgery in Syria. Especially in the early years, the challenges were daunting. We initially performed thoracic, vascular, and closed-heart operations while dealing with inadequate facilities, bureaucratic delays, and poorly qualified personnel. After our independent surgical center was established in early 1976, we performed 1 open-heart and 1 closed-heart procedure per day. Open-heart procedures evolved from the few and simple to the multiple and complex, and we solved difficulties as they arose. Today, our cardiac surgical center occupies an entire 6-floor building. We have 12 …

Micro-Ultrasonographic Imaging Of Atherosclerotic Progression And Correlation With Inflammatory Markers In Apolipoprotein-E Knockout Mice, Rong-Juan Li, Ya Yang, Yan-Hong Wang, Jin-Jie Xie, Li Song, Zheng Wang, Yao-Zhong Zhang, Yan-Wen Qin, Zhi-An Li, Xiao-Shan Zhang

The Texas Heart Institute Journal

We studied prospectively whether atherosclerotic progression in apolipoprotein-E knockout mice could be noninvasively and accurately measured by use of high-resolution ultrasonographic biomicroscopy. We examined the correlation between the ultrasonographic characterization of ascending aortic atherosclerotic plaque and plasma C-reactive protein, interleukin-1, and interleukin-6 levels in these mice.

In 4 age groups (8, 16, 24, and 32 wk) of 8 male knockout mice each (atherosclerotic groups) and age-matched male C57BL/6 mice (control groups), we used ultrasonographic biomicroscopy to measure maximal plaque thickness or intima-media thickness in the ascending aorta. We compared the findings with corresponding histologic measurements, and we measured plasma C-reactive …

Cd34-Positive Stem Cells In The Treatment Of Heart And Vascular Disease In Human Beings, Alexander R Mackie, Douglas W Losordo

The Texas Heart Institute Journal

Bone marrow-derived CD34(+) cells are a well-characterized population of stem cells that have traditionally been used clinically to reconstitute the hematopoietic system after radiation or chemotherapy. More recently, CD34(+) cells have also been shown to induce therapeutic angiogenesis in animal models of myocardial, peripheral, and cerebral ischemia. The mechanism by which CD34(+) cells promote therapeutic angiogenesis is not completely understood, although evidence supports both direct incorporation of the cells into the expanding vasculature and paracrine secretion of angiogenic growth factors that support the developing microvasculature. Phase I and phase II clinical trials have explored the usefulness of CD34(+) cells in …

Mechanical Behavior Of Fully Expanded Commercially Available Endovascular Coronary Stents, Josip Tambaca, Suncica Canic, Mate Kosor, R David Fish, David Paniagua

The Texas Heart Institute Journal

The mechanical behavior of endovascular coronary stents influences their therapeutic efficacy. Through computational studies, researchers can analyze device performance and improve designs. We developed a 1-dimensional finite element method, net-based algorithm and used it to analyze the effects of radial loading and bending in commercially available stents. Our computational study included designs modeled on the Express, Cypher, Xience, and Palmaz stents.

We found that stents that did not fully expand were less rigid than the fully expanded stents and, therefore, exhibited larger displacement. Stents with an open-cell design, such as Express-like or Xience-like stents, had a higher bending flexibility. Stents …

Heterogeneity Of Left Ventricular Signal Characteristics In Response To Acute Vagal Stimulation During Ventricular Fibrillation In Dogs, Alireza Nazeri, Macarthur A Elayda, Lubomir Dragnev, Christopher M Frank, Jihong Qu, Valtino X Afonso, Abdi Rasekh, Mohammad Saeed, Jie Cheng, Mossaab Shuraih, Ali Massumi, Mehdi Razavi

The Texas Heart Institute Journal

Studies have shown that long-term vagal stimulation is protective against ventricular fibrillation; however, the effects of acute vagal stimulation during ventricular fibrillation in the normal heart have not been investigated. We examined the effects of acute vagal stimulation on ventricular fibrillation in a canine model. In 4 dogs, we induced 30-second periods of ventricular fibrillation by means of intraventricular pacing. During 2 of the 4 periods of fibrillation that we analyzed, vagal stimulation was delivered through electrodes in the caudal ends of the vagus nerves. Noncontact unipolar electrograms were recorded from 3 ventricular regions: the basal septum, apical septum, and …

Endovascular Repair Of Aortoesophageal And Aortobronchial Fistulae, Roberto Chiesa, Andrea Kahlberg, Yamume Tshomba, Enrico M Marone, Massimiliano M Marrocco-Trischitta, Germano Melissano

The Texas Heart Institute Journal

Aortoesophageal fistulae (AEF) and aortobronchial fistulae (ABF) are uncommon, but are in general fatal if left untreated. Conventional treatment requires surgical replacement of the thoracic aorta, along with several adjunctive procedures to repair the esophageal or tracheobronchial lesion.The mortality rates associated with open surgery reach 61% in cases of primary fistula and 78% in secondary fistula.

Thoracic endovascular aortic repair (TEVAR) has been proposed as an alternative strategy to surgical management.Although less invasive, this technique has important limitations in treating AEF and ABF, the chief of which is the high risk of graft contamination. Moreover, we still lack sufficient data …

A Comparative Study Of Embedded And Anesthetized Zebrafish In Vivo On Myocardiac Calcium Oscillation And Heart Muscle Contraction, Brian S. Muntean, Christine M. Horvat, James H. Behler, Wissam A. Aboualaiwi, Andromeda M. Nauli, Frederick E. Williams, Surya M. Nauli

Pharmacy Faculty Articles and Research

The zebrafish (Danio rerio) has been used as a model for studying vertebrate development in the cardiovascular system. In order to monitor heart contraction and cytosolic calcium oscillations, fish were either embedded in methylcellulose or anesthetized with tricaine. Using high-resolution differential interference contrast and calcium imaging microscopy, we here show that dopamine and verapamil alter calcium signaling and muscle contraction in anesthetized zebrafish, but not in embedded zebrafish. In anesthetized fish, dopamine increases the amplitude of cytosolic calcium oscillation with a subsequent increase in heart contraction, whereas verapamil decreases the frequency of calcium oscillation and heart rate. Interestingly, verapamil also …

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 …

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: …

Incidence Of, Predictors For, And Mortality Associated With Malignant Ventricular Arrhythmias In Non-St Elevation Myocardial Infarction Patients., Shuchita Gupta, Md, Gregg S. Pressman, Vincent M. Figueredo, M.D.

Division of Cardiology Faculty Papers

BACKGROUND: The incidence of non-ST elevation myocardial infarction (NSTEMI) is increasing. Although life-threatening ventricular arrhythmias have been well-documented in patients with ST elevation MI (STEMI), their incidence and importance in NSTEMI have not been examined in similar detail. We examined the incidence, predictors, and mortality rates of ventricular arrhythmias in a cohort of NSTEMI patients undergoing an early invasive strategy.

METHODS: Consecutive patients admitted with NSTEMI who underwent cardiac catheterization within 48 h of admission were identified by chart review. Presence and type of ventricular arrhythmias and 30-day mortality were recorded. Malignant arrhythmias were defined as sustained ventricular tachycardia (VT, …

Influence Of Sex On Long-Term Outcomes After Percutaneous Coronary Intervention With The Paclitaxel-Eluting Coronary Stent: Results Of The "Taxus Woman" Analysis, Ghada W. Mikhail Md, Robert T. Gerber Md, Phd, David A. Cox Md, Stephen G. Ellis Md, John M. Lasala Md, Phd, John A. Ormiston Mbchb, Gregg W. Stone Md, Mark A. Turco Md, Anita A. Joshi Phd, Donald S. Baim Md, Antonio Colombo Md

Department of Medicine

No abstract provided.

Cardiac Surgery In Octogenarians, Asmatullah Khan, Hassan Khan, Saulat H. Fatimi, Asadullah Khan

Section of Cardiothoracic Surgery

In Europe and North America, cardiac surgery can be done successfully on octogenarians, but differences in patient selection, surgical and bypass techniques prevent us from concluding similarly in Pakistan. This study investigated the short and long-term outcomes of cardiac surgery in octogenarians operated over a 5 years period at The Aga Khan University Hospital, from January 2001 to December 2006. Seventeen octogenarians, (mean age 81.7 ± 2.3) underwent coronary artery bypass graft (CABG). Thirty-days hospital mortality was reported in only 1 patient. Surgical complication of any kind was reported in 13 (76.5%) patients with pleural effusion being the commonest in …