[Experimental production of tricuspid valve and papillary muscle lesions by premature ventricular contractions due to ventricular stimulation in rabbits].
Ventricular bigeminy or trigeminy can spontaneously occur in anesthetized rabbits forced into the supine position. Premature ventricular contractions (PVCs) of this type are characterized by a long coupling time and superimposition of the following P waves. Rabbits with PVCs of this type frequently develop peculiar mitral complex lesions which are detected by deposition of colloidal carbon. This study examined the effects on the tricuspid complex of artificial PVCs induced by left ventricular pacing in rabbits. Anesthetized rabbits were forced into the supine position under electrocardiographic monitoring. The animals were divided into those with spontaneous PVCs, those with artificial PVCs, and those without PVCs as controls. Colloidal carbon (1 ml) was intravenously injected into the animals the next day. All animals were sacrificed after 1 week. Tricuspid complex lesions were found in 2.0% of animals with spontaneous PVCs, in 17.6% of those with artificial PVCs, and in none of the controls. These results indicate that artificial PVCs induced by left ventricular pacing can cause peculiar tricuspid complex lesions.
Ashida
T
T
Division of Cardiovascular Diseases, Asahi Life Foundation, Tokyo.
Kiraku
J
J
Sakurai
S
S
Takahashi
N
N
Fujii
J
J
D000818:Animals; D002304:Cardiac Pacing, Artificial; D004558:Electric Stimulation; D004562:Electrocardiography; D006352:Heart Ventricles; D010210:Papillary Muscles / Q000473:pathology*; D011817:Rabbits; D014261:Tricuspid Valve / Q000473:pathology*; D018879:Ventricular Premature Complexes / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*