752-2 Intra-coronary Contrast Echocardiography Predicts Myocardial Viability Prior to PTCA

Abstract

A rapid method for predicting myocardial viability prior to revascularisation remains elusive. Intra-coronary contrast echocardiography (ICE) evaluates myocardial perfusion and may have a role in predicting myocardial viability by demonstrating flow at a microvascular level. ICE was performed before PTCA in 14 patients who had a wall motion abnormality associated with the index artery (LAD = 11 RCA = 3). There were 10 men and 4 women with a mean age of 63 years (range 54–74 years). Echo derived wall motion score and global ejection fraction were calculated before PTCA and again at 1 month. Linear ultrasound contrast echo data was digitally stored on optical disc and quantified using a specially developed software package. Measured parameters were peak contrast effect (P), area under the contrast echo curve (A). time to peak contrast effect, contrast half-time and mean transit time. Contrast effect in the myocardial bed of the index artery (i) was also compared with that in a reference bed supplied by a normal artery (r). Nine patients (“viable group”) had an improvement in echo score at 1 month while 5 patients (“non-viable” group) had no improvement. The “viable” patients had an improvement in ejection fraction (52.1% to 55.5%, P < 0.02) as well as wall motion index score (1.4 to 1.1, p < 0.04) while the “non-viable” patients had no significant improvement in either parameter (49.0% to 42.8% and 1.5 to 1.61. Significant contrast data was:Empty CellP(i)P(i)/P(r)A(i)A(i)/A(r)“Viable”1.840.5466.10.51“Non-viable”0.640.2220.00.22p valuep < 0.04P < 0.01P < 0.02P < 0.05 P and A were significantly greater in the index myocardial bed in the “viable” group compared to the “non-viable” group. Despite a patent epicardial index coronary artery, 4/5 patients in the “non-viable” group demonstrated minimal contrast effect in the index myocardial segment. These initial results suggest that ICE prior to PTCA may be rapidly used to predict improvement in both regional and global left ventricular function. The contrast data is additive to that obtained by angiography and identification of a contrast “watershed” value should enable a valuable echo predictor of myocardial viability.