Frequency potentiation of contractile function is a major mechanism of the increase in myocardial performance during exercise. In heart failure (HF), this positive force-frequency relation is impaired, and the abnormal left ventricular (LV)-arterial coupling is exacerbated by tachycardia. A myofilament Ca(2+) sensitizer, levosimendan, has been shown to improve exercise tolerance in HF. This may...

effects of acute systemic hypoxia on the cardiovascular system (cys) and respiration of spontaneously breathing cats were studied in two conditions. 1): hypoxic air (6-8% 02 in n2) was given to the animal to induce systemic hypoxia for 20 minutes. hyperventilation at this condition lowered arterial c02 tension (pac02 hypocapnia). 2): in the second run, induction of hypocapnia was prevented by a...

base deficit is a non-respiratory indicator of acid base status. aim of this study is to assess relationship between the base deficit value in immediate post operative period of cabg and valvular heart disease with cardiopulmonary and in hospital outcome of patient. a total of 136 consecutive with cabg and valvular heart disease scheduled in study. 20 variables were determined during the pre-in...

arteritis due to strongylus vulgaris is a well-known cause of colic in horses and donkeys. the current report describes a fatal incidence of arterial obstruction in cranial mesenteric artery caused by s. vulgaris infection in an adult donkey in which anthelmintic treatment was not regularly administered. necropsy findings of the abdominal cavity revealed a complete cranial mesenteric arterial o...

We hypothesize that upright cognitive impairment in patients with postural tachycardia syndrome (POTS) is caused by reduced cerebral blood flow (CBF). The CBF velocity (CBF(v)) measured by transcranial Doppler ultrasound decreased excessively during 70° tilt in a minority of patients with intermittent hyperpnea/hypocapnia. Incremental tilt showed no difference in mean CBF(v). But N-back memory ...

Arterial smooth muscles behave like a syncytium, since they are electrically coupled. It is generally assumed that electrical coupling and dye coupling are mediated by gap junctions. No gap junctions could be detected by transmission electron microscopy in media of coronary arteries. We looked for the presence of gap junction protein in vascular smooth muscle by immunohistochemistry with light ...

Ventricular/vascular coupling dynamics and regional hemodynamics of five hypertensive baboons with concentric left ventricular (LV) hypertrophy (mean arterial pressure +/- SD, 148 +/- 16 mm Hg; LV mass/body weight ratio 3.42 +/- 0.8) were compared with five normotensive controls (mean arterial pressure 89 +/- 3 mm Hg; LV mass/body wt ratio 2.73 +/- 0.5) at different mean arterial pressures. Ven...

OBJECTIVES This study is designed to investigate the effects of anti-hypertensive monotherapy [either calcium channel blocker (CCB) or angiotensin receptor blocker (ARB)] on pulsatile hemodynamic parameters in patients with uncomplicated hypertension. METHODS This is a longitudinal observational study. For simplicity, we included patients with uncomplicated hypertension who receivedmono anti-...

Sympathetic neural activation of vascular smooth muscle ^-receptors induces membrane hyperpolarization and arterial relaxation. This response, which likely is mediated by the G, protein-adenylyl cyclase-cyclic AMP signaling cascade, is reduced in some hypertensive animal models and in human essential hypertension. Since reduced preceptor-mediated vasodilation is a potential mechanism for enhanc...