Radionuclide ventriculographic responses to graded supine and upright exercise: Critical role of the Frank-starling mechanism at submaximal exercise Academic Article Article uri icon

Overview

MeSH Major

  • Cardiovascular Diseases
  • Echocardiography
  • Image Enhancement
  • Neoplasms

abstract

  • To assess the influence of work load and posture on the response to exercise, 25 patients with coronary artery disease (CAD) and 17 normal subjects underwent graded supine and upright exercise radionuclide ventriculography. In both groups, end-diastolic counts increased with supine exercise (p less than 0.001). The ejection fraction and peak systolic pressure-end-systolic volume relation increased in normal subjects (p less than 0.02), but not in patients with CAD. At upright rest, end-diastolic counts decreased in both groups (p less than 0.001) and then increased with exercise (p less than 0.001). The increase in end-diastolic counts was most pronounced on the transition from upright rest to the 150-kpm work load and resulted in a significant increase in stroke counts (p less than 0.05) for both patients with CAD and normal subjects, without a measurable change in the ejection fraction or the peak systolic pressure-end-systolic volume relation. Later in exercise, end-diastolic counts plateaued, and the ejection fraction and the peak systolic pressure, end-systolic volume relation increased only among normal subjects. Thus, low-level upright exercise is highly dependent on the Starling mechanism in both normal subjects and patients with CAD, with enhanced contractility apparent only during more vigorous exercise in normal subjects.

publication date

  • June 1984

Research

keywords

  • Academic Article

Identity

Digital Object Identifier (DOI)

  • 10.1016/0002-9149(84)90600-3

PubMed ID

  • 6731313

Additional Document Info

start page

  • 1671

end page

  • 7

volume

  • 53

number

  • 11