These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Regional myocardial capillary erythrocyte transit time in the normal resting heart.
    Author: Allard MF, Kamimura CT, English DR, Henning SL, Wiggs BR.
    Journal: Circ Res; 1993 Jan; 72(1):187-93. PubMed ID: 8417841.
    Abstract:
    A major determinant of oxygen transport to the myocardium is the time spent by the erythrocytes (red blood cells [RBCs]) traversing the microcirculation. Although it has been shown that the myocardium has regional differences in blood volume, blood flow, metabolism, and sensitivity to ischemic injury, the regional distribution of RBC transit times through the myocardial capillaries has not been previously measured. The present study was designed to measure the regional myocardial capillary RBC transit time by a new technique to determine whether there are regional differences in the capillary RBC transit time in the normal resting heart. Anesthetized open-chest male New Zealand White rabbits (3.0-3.7 kg, n = 8) were studied. Regional myocardial blood volume was determined using chromium-51-labeled RBCs, and regional blood flow was measured using a reference flow technique and a left atrial injection of 15-microns-radiolabeled (gadolinium-153, 10-20 muCi) microspheres. Capillary blood volume was determined by multiplying the regional blood volume by the histologically determined fraction of the total blood volume that was in the capillaries. Capillary RBC transit time was calculated as the quotient of capillary blood volume and blood flow. The myocardial capillary blood volume was the same in the endocardium and the epicardium (4.67 +/- 0.67 ml/100 g for endocardium versus 4.52 +/- 0.70 ml/100 g for epicardium, p = NS), whereas myocardial blood flow tended to be greater in the endocardium (6.09 +/- 0.73 ml/sec per 100 g for endocardium versus 5.47 +/- 0.75 ml/sec per 100 g for epicardium), although this was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)
    [Abstract] [Full Text] [Related] [New Search]