A 49-year-old woman presented to the hospital with shortness of breath 2 weeks after a left total hip replacement. She was found have submassive pulmonary embolism (PE), her case complicated by detection large mobile clot in transit extending through patent foramen ovale between right and atria. The presence this free-floating heart thrombus (FFRHT) increases risks stroke mortality, yet optimal...

We read with great interest the study by Boixel et al. (1), which examines the importance of matrix metalloproteinase (MMP) system in atrial remodeling in a rat model of heart failure. The investigators demonstrate the up-regulation of MMP-2 and MMP-9 in the atria with marked structural abnormalities, but there were no significant differences in tissue inhibitors of MMP (TIMP) activity. The cli...

The effect of quinidine on unidirectional fluxes of Na and K in isolated rabbit atria has been investigated and correlated with known effects of the drug on the electrical and mechanical properties of the heart. Quinidine caused a rapid inhibition of J\a entry, which secondarily depressed K efflux. In addition, the drug depressed membrane permeability to K and caused a marked inhibition of acti...

The ability of the developing myocardium to tolerate oxidative stress during early gestation is an important issue with regard to possible detrimental consequences for the fetus. In the embryonic heart, antioxidant defences are low, whereas glycolytic flux is high. The pro- and antioxidant mechanisms and their dependency on glucose metabolism remain to be explored. Isolated hearts of 4-day-old ...

We performed a correlative electrophysiological and immunohistochemical study of embryonic chicken hearts during the septational period (Hamburger and Hamilton stages 13-31 [2-7 days of incubation]). The analyses yield conclusive evidence for slow conduction, up to 7 days of development, in the outflow tract, in the atrioventricular canal, and in the sinoatrial junction. The conduction velocity...

AIMS Animal studies show that transforming growth factor-β1 (TGF-β1) is an important mediator of atrial fibrosis and atrial fibrillation (AF). This study investigated the role of TGF-β1 in human AF and the mechanism of atrial-selective fibrosis. METHODS AND RESULTS Atrial specimens from 17 open heart surgery patients and left atrial and ventricular specimens from 17 explanted hearts were coll...

Angiotensin II (A II) and analogues were tested for their ability to restore electrical and mechanical activity to cardiac muscle preparations in which the fast Na+ channels had been inactivated by partial depolarization (22-27 mM K+) or by tetrodotoxin (TTX). The partially depolarized or TTX-blocked preparations were chosen because under these conditions electrical and mechanical responses are...

Real-time images of the heart from within the esophagus are produced by a new intraesophageal ultrasonic sector scanner. Sixty images per second are displayed on a gray scale CRT in real-time and recorded on standard videotape for review. By interactive positioning of the esophageal probe, heart ventricles, atria, and valves can be visualized and their dynamics can be studied. The esophageal pr...

BACKGROUND In various heart disease paradigms, atria show stronger fibrotic responses than ventricles. The possibility that atrial and ventricular fibroblasts respond differentially to pathological stimuli has not been examined. METHODS AND RESULTS We compared various morphological, secretory, and proliferative response indexes of canine atrial versus ventricular fibroblasts. Cultured atrial ...

RATIONALE The second heart field (SHF) contains progenitors of all heart chambers, excluding the left ventricle. The SHF is patterned, and the anterior region is known to be destined to form the outflow tract and right ventricle. OBJECTIVE The aim of this study was to map the fate of the posterior SHF (pSHF). METHODS AND RESULTS We examined the contribution of pSHF cells, labeled by lipophi...