Off-pump surgical thrombectomy for subacute right atrial thrombus: A case report.

Right heart thrombi can be seen in a minority of patients with acute pulmonary embolism and are associated with an increased mortality risk. The optimal treatment option comprises thrombolysis or surgical thrombectomy either with catheterbased interventions or with open surgery. Open right atrial thrombectomy is usually performed under cardiopulmonary bypass due to the need for concomitant pulmonary embolectomy.

Long-term risk of arch complications in Loeys Dietz syndrome patients undergoing proximal ascending aortic replacement.

Purpose: Loeys-Dietz syndrome (LDS) is a rare connective tissue disorder. In LDS patients with normal arch morphology, whether the arch should be prophylactically replaced at the time of proximal aortic replacement remains unknown. We evaluated the risk of long-term arch complications in genetically confirmed LDS patients who underwent proximal ascending aortic replacement.

Heart transplant outcomes in recipients of Centers for Disease Control (CDC) high risk donors.

Background: A lack of donor hearts remains a major limitation of heart transplantation. Hearts from Centers for Disease Control (CDC) high-risk donors can be utilized with specific recipient consent. However, outcomes of heart transplantation with CDC high-risk donors are not well known.

Precisely parameterized experimental and computational models of tissue organization.

Patterns of cellular organization in diverse tissues frequently display a complex geometry and topology tightly related to the tissue function. Progressive disorganization of tissue morphology can lead to pathologic remodeling, necessitating the development of experimental and theoretical methods of analysis of the tolerance of normal tissue function to structural alterations. A systematic way to investigate the relationship of diverse cell organization to tissue function is to engineer two-dimensional cell monolayers replicating key aspects of the in vivo tissue architecture.

An enhancer polymorphism at the cardiomyocyte intercalated disc protein NOS1AP locus is a major regulator of the QT interval.

QT interval variation is assumed to arise from variation in repolarization as evidenced from rare Na- and K-channel mutations in Mendelian QT prolongation syndromes. However, in the general population, common noncoding variants at a chromosome 1q locus are the most common genetic regulators of QT interval variation. In this study, we use multiple human genetic, molecular genetic, and cellular assays to identify a functional variant underlying trait association: a noncoding polymorphism (rs7539120) that maps within an enhancer of NOS1AP and affects cardiac function by increasing NOS1AP transcript expression.

IK1 heterogeneity affects genesis and stability of spiral waves in cardiac myocyte monolayers.

Previous studies have postulated an important role for the inwardly rectifying potassium current (I(K1)) in controlling the dynamics of electrophysiological spiral waves responsible for ventricular tachycardia and fibrillation. In this study, we developed a novel tissue model of cultured neonatal rat ventricular myocytes (NRVMs) with uniform or heterogeneous Kir2.1expression achieved by lentiviral transfer to elucidate the role of I(K1) in cardiac arrhythmogenesis.

Cell cultures as models of cardiac mechanoelectric feedback.

Although stretch-activated currents have been extensively studied in isolated cells and intact heart in the context of mechanoelectric feedback (MEF) in the heart, quantitative data regarding other mechanical parameters such as pressure, shear, bending, etc, are still lacking at the multicellular level. Cultured cardiac cell monolayers have been used increasingly in the past decade as an in vitro model for the studies of fundamental mechanisms that underlie normal and pathological electrophysiology at the tissue level. Optical mapping makes possible multisite recording and analysis of action potentials and wavefront propagation, suitable for monitoring the electrophysiological activity of the cardiac cell monolayer under a wide variety of controlled mechanical conditions.

Lentiviral vector-mediated expression of GFP or Kir2.1 alters the electrophysiology of neonatal rat ventricular myocytes without inducing cytotoxicity.

Recombinant lentiviral vectors (LVs) are capable of transducing neonatal rat ventricular myocytes (NRVMs) and providing stable, long-term transgene expression. The goal of the present study was to comprehensively test whether transduction of NRVMs by LVs results in cytotoxicity and to examine the electrophysiological consequences of gene modification of NRVM monolayers by two vectors: one encoding a putatively inert enhanced green fluorescent protein (eGFP) and the other a major ion channel protein, inward rectifier K(+) channel (Kir) 2.1.

Gene transfer of connexin43 mutants attenuates coupling in cardiomyocytes: novel basis for modulation of cardiac conduction by gene therapy.

Modification of electrical conduction would be a useful principle to recruit in preventing or treating certain arrhythmias, notably ventricular tachycardia (VT). Here we pursue a novel gene transfer approach to modulate electrical conduction by reducing gap junctional intercellular communication (GJIC) and hence potentially modify the arrhythmia substrate. The ultimate goal is to develop a nondestructive approach to uncouple zones of slow conduction by focal gene transfer.

Proarrhythmic potential of mesenchymal stem cell transplantation revealed in an in vitro coculture model.

Background: Mesenchymal stem cells (MSCs) are bone marrow stromal cells that are in phase 1 clinical studies of cellular cardiomyoplasty. However, the electrophysiological effects of MSC transplantation have not been studied. Although improvement of ventricular function would represent a positive outcome of MSC transplantation, focal application of stem cells has the potential downside of creating inhomogeneities that may predispose the heart to reentrant arrhythmias.

Fluorescence resonance energy transfer (FRET) microscopy imaging of live cell protein localizations.

The current advances in fluorescence microscopy, coupled with the development of new fluorescent probes, make fluorescence resonance energy transfer (FRET) a powerful technique for studying molecular interactions inside living cells with improved spatial (angstrom) and temporal (nanosecond) resolution, distance range, and sensitivity and a broader range of biological applications.