Regional heterogeneity of myocardial blood flow within the rabbit left ventricle during haemorrhagic hypotension

• Autorzy: Standa M , Iversen P.O. , Flatebo T. , Nicolaysen G.
• Języki publikacji: EN

Abstrakty

EN

Several studies have reported an extensive regional heterogeneity in myocardial blood flow. The reported coefficients of variation for regional myocardial perfusion range from about 0.2 to 0.4 in normotensive animals. The spatial distribution of myocardial perfusion during haemorrhagic hypotension seems not to have been assessed. The goal of the present study was to determine the regional heterogeneity in myocardial blood flow within the rabbit left ventricle during normal conditions and after haemorrhagic hypotension. Radioactive microspheres were infused into the left ventricle in barbiturate anaethetized rabbits over either 30 or 120 sec. The haemorrhagic hypotension was induced by bleeding, so that mean arterial blood pressure was reduced to about 50% of control. The left ventricles were divided into samples of about 0.025 g each. Regional heterogeneity in the blood flow was expressed as the coefficient of variation corrected for the Poisspn distribution of microspheres (CVc). The CVc was 0.37 ±0.09 (mean±SD) during control and 0.41+0.11 after bleeding, the CVc obtained after bleeding being somewhat higher than during control (P<0.05). We obtained a high correlation coefficient (τ about 0.68) between regional perfusion values at control and after bleeding which indicates a stable perfusion pattern within the myocardium. We conclude that the regional distribution of coronary blood flow within the left ventricle is markedly heterogenous during control condition and that this pattern is not changed during haemorrhagic hypotension.

Słowa kluczowe

EN

ventricle; left ventricle; hemorrhagic hypertension; microsphere; blood; blood flow; arterial blood; blood pressure; physiology; regulation; myocardium; hemorrhage; heterogeneity; rabbit

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 1992
• Tom: 43
• Numer: 3
• Opis fizyczny: p.209-218,fig.

Twórcy

autor

Standa M

• School of Medicine, ul.Chalubinskiego 10, 50-368 Wroclaw, Poland

autor

Iversen P.O.

autor

Flatebo T.

autor

Nicolaysen G.

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