The effect of the autonomic system on conduction disorders in the infarction zone (IZ) and related reentrant ventricular arrhythmias (RVA) in the late myocardial infarction period in the dog was studied utilizing averaged recordings of the reentrant pathways from the epicardial surface of the IZ. Vagal (V) stimulation was found to have no significant direct electrophysiologic effect while sympa...

UNLABELLED The genetic diversity of rotavirus A (RVA) strains is facilitated in part by genetic reassortment. Although this process of genome segment exchange has been reported frequently among mammalian RVAs, it remained unknown if mammalian RVAs also could package genome segments from avian RVA strains. We generated a simian RVA strain SA11 reassortant containing the VP4 gene of chicken RVA s...

The right ventricular apex (RVA) is a potential hot spot for development of cardiac rhythm anomalies. Many conditions, including arrhythmogenic right ventricular cardiomyopathy and Brugada's syndrome affect the RVA, and further, the RVA remains an incompletely characterized pacing region. Whether there are structural reasons underlying these conduction properties remains unsettled. In the curre...

OBJECTIVE To assess, by socioeconomic setting, the effect of nationwide vaccination against species A rotavirus (RVA) on childhood diarrhoea-related hospitalizations in Mexico. METHODS Data on children younger than 5 years who were hospitalized for diarrhoea in health ministry hospitals between 1 January 2003 and 31 December 2011 were collected from monthly discharge reports. Human developmen...

Diarrheal diseases (DD) have distinct etiological profiles in immune-deficient and immune-competent patients. This study compares detection rates, genotype distribution and viral loads of different enteric viral agents in HIV-1 seropositive (n = 200) and HIV-1 seronegative (n = 125) children hospitalized with DD in Rio de Janeiro, Brazil. Except for group A rotavirus (RVA), which were detected ...

BACKGROUND Identifying the septal versus lateral site of origin of ventricular tachycardia (VT) with a right bundle-branch block (RBBB)-type pattern and an R-S ratio >1 in lead V1 is difficult with the 12-lead ECG, especially in patients with prior apical infarction. METHODS AND RESULTS We prospectively evaluated 58 patients with VT. Sixteen patients had apical infarcts (group 1), 29 had nona...

Background and Objectives: Long-term right ventricular (RV) apex pacing has been associated with left ventricular (LV) systolic dysfunction. However, pacing in the RV outflow tract (RVOT) is associated with a narrower QRS duration and may have a more normal LV activation in comparison to RV apical (RVA) pacing. We hypothesized that RVOT pacing is associated with less mechanical dyssynchrony com...

Resynchronization is frequently used for the treatment of heart failure, but the mechanism for improvement is not entirely clear. In the present study, the temporal synchrony and spatiotemporal distribution of left ventricular (LV) contraction was investigated in eight dogs during right atrial (RA), right ventricular apex (RVa), and biventricular (BiV) pacing using tagged magnetic resonance ima...

Previous studies in pigeons have shown that the neurons in the medial column of the inferior olive respond best to patterns of optic flow resulting from self-rotation. With respect to the axis of rotation, there are two functional groups: rVA neurons prefer rotation about the vertical axis, whereas rH45 neurons respond best to rotation about an horizontal axis oriented at 45 degrees ipsilateral...

OBJECTIVES We evaluated the acute impact of different cardiac pacing sites on two-dimensional speckle-tracking echocardiography (STE) derived left ventricular (LV) rotation and twist in healthy dogs. METHODS Twelve dogs were used in this study. The steerable pacing electrodes were positioned into right heart through the superior or inferior vena cava, into LV through aorta across the aortic v...