Right ventricular remodeling in idiopathic pulmonary arterial hypertension: adaptive versus maladaptive morphology.

Background: Although increased pulmonary pressure is caused by changes in the pulmonary vasculature, prognosis in idiopathic pulmonary arterial hypertension (IPAH) is strongly associated with right ventricular (RV) function. The aim of this study was to describe the best RV adaptive remodeling pattern to increased afterload in IPAH.

Methods: In 60 consecutive patients with IPAH, RV morphologic and functional features were evaluated by echocardiography and cardiac magnetic resonance imaging.

Right ventricular dyssynchrony in idiopathic pulmonary arterial hypertension: determinants and impact on pump function.

Background: Right ventricular (RV) dyssynchrony has been described in pulmonary arterial hypertension (PAH), but no evidence is available on its morphologic determinants and its effect on systolic function. The aim of this study was to evaluate the morphologic determinants of RV dyssynchrony by echocardiographic and cardiac magnetic resonance imaging and its effect on systolic function.

Methods: In 60 consecutive idiopathic PAH (IPAH) patients with narrow QRS, RV dyssynchrony was evaluated by 2D speckle-tracking echocardiography, calculating the standard deviation of the times to peak systolic strain for the four mid-basal RV segments (RV-SD4).

The h-current in periglomerular dopaminergic neurons of the mouse olfactory bulb.

The properties of the hyperpolarization-activated cation current (I(h)) were investigated in rat periglomerular dopaminergic neurons using patch-clamp recordings in thin slices. A reliable identification of single dopaminergic neurons was made possible by use of a transgenic line of mice expressing eGFP under the tyrosine hydroxylase promoter. At 37 °C and minimizing the disturbance of the intracellular milieu with perforated patches, this current shows a midpoint of activation around -82.

The h-current in the substantia Nigra pars compacta neurons: a re-examination.

The properties of the hyperpolarization-activated cation current (I(h)) were investigated in rat substantia nigra - pars compacta (SNc) principal neurons using patch-clamp recordings in thin slices. A reliable identification of single dopaminergic neurons was made possible by the use of a transgenic line of mice expressing eGFP under the tyrosine hydroxylase promoter. The effects of temperature and different protocols on the I(h) kinetics showed that, at 37°C and minimizing the disturbance of the intracellular milieu with perforated patch, this current actually activates at potentials more positive than what is generally indicated, with a half-activation potential of -77.

Relationship between baseline ET-1 plasma levels and outcome in patients with idiopathic pulmonary hypertension treated with bosentan.

Objectives: To address if baseline endothelin-1 (ET-1) plasma levels might predict clinical worsening (CW) in patients with idiopathic pulmonary hypertension (IPAH) treated with bosentan.

Methods: Forty-four consecutive patients with IPAH (WHO classes II-III) were included in this study. After an initial assessment (clinical status, pulmonary hemodynamics, samples for adrenomedullin (ADM), ET-1 and brain natriuretic peptide (BNP) plasma levels), patients were treated with bosentan and followed-up for CW.