Cardiac repair in a porcine model of acute myocardial infarction with human induced pluripotent stem cell-derived cardiovascular cells.

Human induced pluripotent stem cells (hiPSCs) hold promise for myocardial repair following injury, but preclinical studies in large animal models are required to determine optimal cell preparation and delivery strategies to maximize functional benefits and to evaluate safety. Here, we utilized a porcine model of acute myocardial infarction (MI) to investigate the functional impact of intramyocardial transplantation of hiPSC-derived cardiomyocytes, endothelial cells, and smooth muscle cells, in combination with a 3D fibrin patch loaded with insulin growth factor (IGF)-encapsulated microspheres. hiPSC-derived cardiomyocytes integrated into host myocardium and generated organized sarcomeric structures, and endothelial and smooth muscle cells contributed to host vasculature.

Risk of new-onset atrial fibrillation and stroke after radiofrequency ablation of isolated, typical atrial flutter.

Background: Radiofrequency ablation (RFA) is considered a curative procedure for typical atrial flutter (AFL); however, patients remain at risk for developing new atrial fibrillation (AF).

Objective: The purpose of this study was to determine the incidence and predictors of new-onset AF and stroke after RFA of isolated AFL in a multicenter cohort.

Methods: The study included 315 consecutive patients who underwent successful RFA of isolated, typical AFL from 2006 to 2013 at 4 community and teaching hospitals.

Long-term follow-up of older patients with Mobitz type I second degree atrioventricular block.

Objective: To examine the long-term survival of older patients with Mobitz I second degree atrioventricular (AV) block.

Design: Retrospective cohort study. Propensity score adjustment for requiring a cardiac implantable electronic device (CIED) was performed.

Imaging in catheter ablation for atrial fibrillation: enhancing the clinician's view.

Catheter ablation is an effective treatment for symptomatic atrial fibrillation. A thorough understanding of the left atrium anatomy and its adjacent structures is critical for the success of the procedure and for avoiding complications. Pre-procedural imaging aims at determining left atrial size, anatomy, and function and is also used to rule out an atrial thrombus.

Mast cell tryptase may modulate endothelial cell phenotype in healing myocardial infarcts.

Mast cells and macrophages infiltrate healing myocardial infarcts and may play an important role in regulating fibrous tissue deposition and extracellular matrix remodelling. This study examined the time-course of macrophage and mast cell accumulation in healing infarcts and studied the histological characteristics and protease expression profile of mast cells in a canine model of experimental infarction. Although macrophages were more numerous than mast cells in infarct granulation tissue, macrophage density decreased during maturation of the scar, whereas mast cell numbers remained persistently elevated.

Acute Congestive Heart Failure and Tumor Necrosis Factor Alpha.

Congestive heart failure is prevalent in the elderly; recurrent hospital admissions for acute deterioration is a major health care problem. We examined tumor necrosis factor alpha levels in 31 congestive heart failure patients who were admitted to the hospital due to acute cardiogenic pulmonary edema. Blood samples were taken within 24 hours of admission and at the time of discharge after recovery.