Author + information
- Received June 2, 1986
- Revision received September 16, 1986
- Accepted October 7, 1986
- Published online April 1, 1987.
- Pamela S. Douglas, MD, FACC*,1,
- Nathaniel Reicher, MD1,
- Theodore Plappert1,
- Ali Muhammad1 and
- Martin G. St. John Sutton, MB, MRCP, FACC1
- ↵*Address for reprints: Pamela S. Douglas, MD, Cardiovascular Section, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, Pennsylvania 19104.
M-mode echocardiography measurement of left ventricular fractional shortening and meridional wall stress has been used extensively alone and in combination to describe left ventricular systolic function. To determine whether the improved dimensional information afforded by two-dimensional echocardiography might result in shortening and stress calculations yielding a different view of left ventricular function, we compared two-dimensional and M-mode echocardiograms in 69 subjects (19 normal, 13 with aortic stenosis, 22 with aortic regurgitation and 15 with congestive cardiomyopathy).
Fractional shortening was greater with M-mode than with two-dimensional echocardiography in all subjects, especially in those with cardiomyopathy (p < 0.05). In aortic stenosis, two-dimensional shortening, at 24 ± 5%, was reduced (p < 0.05 versus normal), but M-mode shortening, at 34 ± 5%, was not. M-mode estimates of meridional stress were higher than two-dimensional values, again especially in cardiomyopathy. Two-dimensional echocardiography enabled determination of long-and short-axis ratios, circumferential stress and the ratio of circumferential to meridional stresses. Circumferential stress was elevated in aortic stenosis at 302 ± 65 × 103dynes/cm2, suggesting afterload excess as the cause for the observed reduction in two-dimensional shortening. The more spherical cardiomyopathy hearts had a meridional to circumferential stress ratio closer to 1, such that use of meridional stress alone would overestimate effective afterload.
It is concluded that M-mode and two-dimensional echocardiographic analyses of left ventricular shortening and stress produce different results. Two-dimensional echocardiographic methods may enhance the assessment of ventricular function, especially in patients with aortic stenosis and cardiomyopathy.
- Received June 2, 1986.
- Revision received September 16, 1986.
- Accepted October 7, 1986.
- American College of Cardiology Foundation