A feature of phasic coronary flow patterns recorded in conscious chronically instrumented dogs is the atrial cove--a transient depression of arterial flow that occurs during atrial systole. The association between the hemodynamic effects of atrial systole and the atrial cove was studied in anesthetized dogs and pigs with complete heart block. Many atrial coves are available for study in these p...

One of the most exciting developments in our understanding of atrial fibrillation (AF) over the last several years has been the recognition that AF itself modifies atrial electrical properties in a way that promotes the occurrence and maintenance of the arrhythmia, a process termed 'atrial remodeling'. The principle stimulus for AF-induced atrial remodeling is the rapid atrial rate that results...

Speckle tracking echocardiography (STE) is an imaging technique applied to the analysis of left atrial function. STE provides a non-Doppler, angle-independent and objective quantification of left atrial myocardial deformation. Data regarding feasibility, accuracy and clinical applications of left atrial strain are rapidly gathering. This review describes the fundamental concepts of left atrial ...

BACKGROUND The assessment of left atrial (LA) function by 2-dimensional speckle tracking echocardiography (STE) holds important clinical implications in human medicine. Few similar data are available in dogs. OBJECTIVES To assess LA function by STE in dogs with and without myxomatous mitral valve disease (MMVD), analyzing LA areas, systolic function, and strain. ANIMALS One hundred and fift...

it has been well - established that common atrial flutter is due to intraatrial macroreentry and its reentry circuit locates in the right atrium. this reentry circuit has been characterized to involve an area of slow conduction identifiable electrophysiologically at the low posteroseptal right atrium and anatomical narrow isthmus snrrounded by the inferior vena capa, coronary sinus astium and t...

The objective of this study was to examine the hypothesis that long-term, rapid atrial pacing produces a model of atrial systolic and diastolic dysfunction but does not alter ventricular function. Eight dogs were atrially paced at 400 beats/min (3:1-5:1 ventricular response) for 6 wk and subsequently instrumented with left atrial (LA) and left ventricular (LV) sonomicrometers and micromanometer...