The effect of postural changes (leg lifting) on tissue Doppler parameters in coronary artery disease

OBJECTIVES
We investigated the effect of increased preload through postural changes (leg lifting) on tissue Doppler parameters in patients with and without coronary artery disease (CAD).

STUDY DESIGN
The study included 42 patients who were scheduled for coronary angiography. All the patients underwent standard two-dimensional, color Doppler and tissue Doppler echocardiography before coronary angiography. Tissue Doppler imaging was performed from septal and lateral mitral annuluses at baseline and during 45º leg lifting followed by two-minute stabilization. Patients were grouped based on coronary angiography findings: those having stenosis greater than 70% were considered to have CAD and those with normal coronary arteries comprised the control group. Echocardiography measurements were compared between the two groups.

RESULTS
Angiography showed normal coronary arteries or border irregularities in 22 patients and CAD in 20 patients. The two groups were similar with regard to demographic data and ejection fractions, except for male preponderance in the CAD group. Compared with the control group, patients with CAD exhibited a significantly lower isovolumic acceleration rate (IVA) at the lateral (p=0.007) and septal (p=0.03) mitral annuluses. In the control group, leg lifting resulted in increased systolic velocity (S) compared with baseline at the lateral (p=0.009) and septal (p=0.01) annuluses, whereas S wave augmentation was only significant at the septal annulus (p=0.009) in patients with CAD. No significant change was observed in IVA following leg lifting in both groups.

CONCLUSION
Preload alteration induced by leg lifting resulted in similar changes in tissue Doppler parameters in patients with and without CAD, except for blunted augmentation of S wave at the lateral annulus in CAD. Detection of decreased IVA at baseline may be a useful finding for CAD.