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THE EXTENT OF THE CAPILLARY BED OF THE HEART

J T Wearn1,

  • 1Thorndike Memorial Laboratory of the Boston City Hospital, and the Department of Medicine, Harvard Medical School, Boston.

The Journal of Experimental Medicine
|October 30, 2009
PubMed

Insights

This study reveals a rich capillary blood supply in normal heart muscle, with about one capillary per muscle fiber in ventricles. This method also aids in studying blood supply in diseased hearts.

Area of Science:

  • Cardiovascular Science
  • Histology
  • Anatomy

Background:

  • Understanding myocardial vascularization is crucial for cardiac health.
  • Previous methods for quantifying capillary density have limitations.

Purpose of the Study:

  • To determine the capillary density in normal heart muscle using a novel injection technique.
  • To compare capillary distribution across different heart regions.
  • To establish a baseline for studying cardiac vascular pathology.

Main Methods:

  • Injections into coronary arteries of beating hearts.
  • Quantification of capillaries per muscle fiber and per unit area.
  • Microscopic examination of injected heart tissue.

Main Results:

  • Normal heart muscle exhibits a dense capillary network, averaging one capillary per muscle fiber in ventricular and papillary muscles.
  • Auricular muscle and Purkinje system show a less abundant capillary supply.
  • Capillary density in ventricular walls is approximately double that of skeletal muscle.
  • Capillaries were not consistently observed in heart valves.

Conclusions:

  • The beating heart has a rich capillary supply, particularly in the ventricles.
  • The described injection method is effective for assessing myocardial vascularization.
  • This technique offers a valuable tool for investigating blood supply in pathological hearts.

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