Thirty-three patients with coronary artery disease (CAD) and 13 subjects without demonstrable cardiac disease were studied with multigated equilibrium blood pool imaging to assess the diagnostic value of exercise-induced alterations in left ventricular (LV) volumes, segmental wall motion, ejection fraction (LVEF), and the end-systolic pressure-volume relationship. In subjects without cardiac disease, left ventricular end-diastolic volume (LVEDV) was 102 ± 7.2 ml (SEM) at rest and 125 ± 9.7 ml at peak exercise (PEx) (p <0.001). Left ventricular end-systolic volume (LVESV) was 35 ± 3.0 ml at rest 29 ± 3.4 ml at PEx (p <0.01). LVEF increased from 0.72 ± 0.02 at rest to 0.82 ± 0.02 at PEx (p <0.001). The nine patients with one-vessel CAD also had an increase in LVEDV (p <0.001) and LVEF (p <0.02) at PEx, but no significant change in LVESV. The 24 patients with significant two- or three-vessel CAD had increases in both LVEDV (196 ± 13.2 ml to 195 ± 13.7 ml, p <0.001) and LVESV (86 ± 12.0 ml to 102 ± 12.0 ml, p <0.01) at PEx and a decrease in LVEF (0.56 ± 0.03 to 0.52 ± 0.03, p <0.05). The relationship between cuff-determined peak systolic blood pressure and LVESV index (P/V index) was used to further characterize alterations in LV function at rest and during PEx. In subjects without cardiac disease, this index rose substantially during PEx (7.6 ± 0.73 at rest vs 14.9 ± 1.78 with PEx, p <0.001). This change was less dramatic in those with one-vessel disease and absent in patients with two- or three-vessel disease (4.2 ± 0.60 at rest vs 3.9 ± 0.50 at PEx, NS). The change in LVESV alone was different in each group. We conclude that the assessment of exercise-induced alterations in LVESV and the P/V index is useful for evaluating LV dysfunction associated with angiographically important coronary artery disease.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Physiology (medical)