Faulty incorporation of the common pulmonary vein leaves it as a distinct structure posteriorly, into which the pulmonary veins empty. This "chamber" is separated from the anterior "fetal" left atrium (containing the left atrial appendage and communicating with the mitral valve) by a diaphragm, and is known as cor triatriatum, one of the rarest of cardiac malformations. Less pronounced but stil...

Objective: To evaluate the acute effects of atrial pacing at different pacing sites on mechanical stunning after cardioversion of atrial fibrillation (AF). Setting: Tertiary referral centre. Patients: 20 patients with persistent AF were studied. Interventions: Spontaneous echo contrast (SEC), left atrial appendage emptying velocity (LAAEV), and left atrial appendage emptying fraction (LAAEF) we...

An isolated aneurysmal dilatation of the left atrial appendage was found in an 18 year old girl who presented with atrial fibrillation and an unusual cardiac shadow on routine chest radiographs. The diagnosis was made by cross sectional echocardiography. The giant appendage was excised to remove the risk of systemic embolism and the need for life long anticoagulation.

Previous studies have shown regional differences in atrial distensibility. We studied 12 open-chest dogs to test the hypothesis that left atrial compliance is decreased after removal of the left atrial appendage and to determine the effect of altered atrial compliance on atrial reservoir and conduit function. Sonomicrometer crystal pairs were used to measure the long- and short-axis diameters o...

Acetylcholinesterase (AChE), the enzyme that degrades acetylcholine, exists as a multiple molecular forms that differ in their quaternary structure and mode of attachment to the cell surface. The distribution of the individual molecular forms of AChE in various cardiac regions with distinct anatomical characteristics was investigated. The results confirmed those of others by showing that the to...