Author + information
- Received November 30, 1987
- Revision received March 9, 1988
- Accepted March 23, 1988
- Published online August 1, 1988.
- ↵∗Address for reprints: B.I. Jugdutt, MBChB, 2C2.43 Walter MacKenzie Health Sciences Centre, University of Alberta, Edmonton, Alberta, T6G 2R7, Canada.
To determine whether the extent of left ventricular dysfunction and the degree of shape distortion can predict outcome in survivors of moderate-sized anterior Q wave myocardial infarction who are undergoing exercise training, these variables were measured by two-dimensional echocardiography before and after 12 weeks of a low level exercise training program starting 15 weeks after infarction in 13 patients (7 in group 1 and 6 in group 2) and 12 weeks apart in 24 matched control patients without training. By the end of training, the functional class score had increased in group 2 (from 2.25 to 2.67, p < 0.005) but had not changed in group 1. Further discrimination of groups 1 and 2 was provided by an initial asynergy (akinesia or dyskinesia, or both) < 18% or ≥ 18%. Compared with group 1, group 2 had greater initial asynergy (32 versus 6%, p < 0.001), expansion index (asynergic/normal endocardial segment length: 1.8 versus 1.6, p < 0.025) and peak shape distortion index (12.2 versus 1.0 mm, p < 0.005) but lower ejection fraction (43 versus 59%, p < 0.05) and thinning ratio (asynergic/normal wall thickness: 0.61 versus 0.74, p < 0.05).
These variables did not change with training in group 1. However, in group 2, training caused significant increase in asynergy (from 32 to 40%, p < 0.05), expansion index (from 1.8 to 2.0, p < 0.01) and peak shape distortion (from 12.2 to 20.9 mm, p < 0.05) associated with a decrease in thinning ratio (from 0.61 to 0.51, p < 0.001) and ejection fraction (from 43 to 30%, p < 0.005). Initial values for these variables were similar for corresponding control groups but did not change over the 12 weeks. Thus, patients with ≥ 18% left ventricular asynergy on the initial echocardiogram showed more shape distortion, expansion and thinning before exercise training and developed further functional and topographic deterioration with training.
↵1 Dr. Michorowski was a Clinical Research Fellow (1985 to 1987) supported by the Alberta Heritage Foundation for Medical Research, Edmonton.
☆ This study was supported in part by a grant from the Canadian Heart Foundation, Ottawa, Ontario, Canada.
☆☆ This paper was presented in part at the Annual National Meeting of the American Federation for Clinical Research, San Diego, California, May 2, 1987.
- Received November 30, 1987.
- Revision received March 9, 1988.
- Accepted March 23, 1988.