Author + information
- Received May 9, 1988
- Revision received June 10, 1988
- Accepted September 15, 1988
- Published online February 1, 1989.
- Pamela S. Douglas, MD, FACC∗,
- Robert Morrow,
- Alfred Ioli and
- Nathaniel Reichek, MD, FACC
- ↵∗Address for reprints:Pamela S. Douglas, MD, Cardiovascular Se ction, Hospital of the University of Pennsylvania, 3400 Spruce Street, Philadelphia, Pennsylvania 19104.
Because idiopathic dilated cardiomyopathy is characterized by elevated wall stress and a more spherical left ventricle, the relations among shape, afterload and survival were examined. Thirty-six patients with cardiomyopathy were prospectively studied by two-dimensional echocardiography. Data included echocardiographic short- and long-axis cavity dimensions, their ratio and, with cuff systolic blood pressure, meridional and circumferential end-systolic stresses and their ratios. Survivors (n = 16) were followed up for 52 months (range 40 to 76); nonsurvivors (n = 20) died an average of 11 months after study.
Survivors had a smaller left ventricular end-diastolic short-axis dimension (6.4 versus 7.1 cm, p < 0.03) but a similar long-axis length (8.6 versus 8.3 cm). However, overall cavity shape or the ratio of short- to long-axis end-diastolic dimensions was more spherical in those with poorer survival (ratio 0.76 versus 0.68, p 0.02). Meridional and circumferential end-systolic stresses were similar in the two groups, but stress was more evenly distributed in the long- and short-axis planes in nonsurvivors (meridional/circumferential stress ratio 0.57 versus 0.52 in survivors, p < 0.05). Improved survival was associated with an end-diastolic short-axis dimension <7.6 cm, a short- to long-axis ratio <0.76 and a meridional to circumferential stress ratio <0.54. Life table analysis revealed a 28% mortality rate in patients with all three of these characteristics compared with 100% in patients with none. Survivors and nonsurvivors did not differ in systolic cavity dimension, wall thickness, relative wall thickness, cavity volume, percent posterior wall thickening or fractional shortening.
In conclusion, a poorer survival was associated with a more spherical ventricle and a more uniform distribution of afterload. In contrast, there was no association between survival and wall thickness, systolic function and endsystolic stress. Two-dimensional echocardiographic determinations of cavity dimension, shape and load distribution may provide useful prognostic information in dilated cardiomyopathy.
☆ We thank Evelyn Robles and Jeanette Forte for excellent secretarial support.
- Received May 9, 1988.
- Revision received June 10, 1988.
- Accepted September 15, 1988.