Biomaterial Database

Left ventricular unloading decreases rate of isovolumic right ventricular pressure decline. 1993

C D Brown, and E Chow, and D J Farrar

Department of Cardiac Surgery, California Pacific Medical Center, San Francisco 94115.

To determine whether direct ventricular interaction affects right ventricular (RV) relaxation, we compared the minimum rate of change of RV pressure (dP/dtmin) and the time constant, tau, of isovolumic RV pressure decline in open-chest, anesthetized pigs following a normal left ventricular (LV) contraction and an acutely unloaded LV contraction. Rapid removal of blood via the LV apex into a prosthetic ventricle during a single systole decreased the LV pressure-time integral 68.3% and peak systolic pressure 49.9% without changing RV end-diastolic conditions. Micromanometers measured ventricular chamber pressures during single RV isovolumic beats, which were produced by transient pulmonary artery occlusion in both the control and the LV-unloaded states. When the LV was unloaded, RV tau rose significantly from 41.7 +/- (SD) 7.1 to 49.8 +/- 9.4 ms, P < 0.005 (pericardium intact) and 42.9 +/- 10.8 to 51.8 +/- 13.9 ms, P < 0.005 (pericardium opened). Simultaneously, RV dP/dtmin decreased from -400.5 +/- 136.6 to -288.3 +/- 46.8 mmHg/s, P = 0.14 (pericardium intact), and -342.4 +/- 104.2 to -241.2 +/- 118.9 mmHg/s, P < 0.01 (pericardium opened). These data indicate that LV systolic unloading decreases the rate of RV relaxation. We conclude that RV relaxation is influenced by direct anatomic ventricular interaction.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009131	Muscle, Smooth, Vascular	The nonstriated involuntary muscle tissue of blood vessels.	Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D009200	Myocardial Contraction	Contractile activity of the MYOCARDIUM.	Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
D010496	Pericardium	A conical fibro-serous sac surrounding the HEART and the roots of the great vessels (AORTA; VENAE CAVAE; PULMONARY ARTERY). Pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. The latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers.	Epicardium,Fibrous Pericardium,Parietal Pericardium,Pericardial Cavity,Pericardial Space,Serous Pericardium,Visceral Pericardium,Cavities, Pericardial,Cavity, Pericardial,Pericardial Cavities,Pericardial Spaces,Pericardium, Fibrous,Pericardium, Parietal,Pericardium, Serous,Pericardium, Visceral,Pericardiums, Fibrous,Pericardiums, Serous,Serous Pericardiums,Space, Pericardial,Spaces, Pericardial
D011651	Pulmonary Artery	The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs.	Arteries, Pulmonary,Artery, Pulmonary,Pulmonary Arteries
D004562	Electrocardiography	Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.	12-Lead ECG,12-Lead EKG,12-Lead Electrocardiography,Cardiography,ECG,EKG,Electrocardiogram,Electrocardiograph,12 Lead ECG,12 Lead EKG,12 Lead Electrocardiography,12-Lead ECGs,12-Lead EKGs,12-Lead Electrocardiographies,Cardiographies,ECG, 12-Lead,EKG, 12-Lead,Electrocardiograms,Electrocardiographies, 12-Lead,Electrocardiographs,Electrocardiography, 12-Lead
D005260	Female		Females
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D006339	Heart Rate	The number of times the HEART VENTRICLES contract per unit of time, usually per minute.	Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia