Exercise-induced alterations in left ventricular volumes and the pressure-volume relationship: a sensitive indicator of left ventricular dysfunction in patients with coronary artery disease.

Thirty-three patients with coronary artery disease (CAD) and 13 subjects without demon- strable 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 ventric- ular 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 and 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 (169 ± 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 substan- tially 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.