**3.2 Feasibility and examples of LAD Doppler velocity sampling**

Sampling of LAD blood velocities was possible at all occasions in all the patients. Colour-Doppler jet of blood velocity through the LAD had distinct boarders and measurement of diameters was possible with inter and intra-observer variability of 0.1±0.05mm and 0.15±0.07mm. Inter and intra-observer variability of LAD velocities were 2±0.4 and 1.5±0.2 cm/sec and of time velocity integrals 0.4±0.1 and 0.3±0.1cm, and of pressure half time 10±3 and 8±3 msec In figure 6, an example of a patient with acute anterior STEMI after primary angioplasty and bare metal stent implantation in the LAD. The velocity profile demonstrates prolonged diastolic deceleration time (more than 600msec) and forward systolic flow. In this patient left ventricular systolic function improved and left ventricular ejection fraction at

Effects of Eptifibatide on the Microcirculation After Primary Angioplasty in

(39%) in those not treated, p=ns (figure 8).

ml/min, p=0.09 (figure 9).

Acute ST-Elevation Myocardial Infarction: A Trans-Thoracic Coronary Artery Doppler Study 67

Diastolic deceleration time of LAD flow averaged 629±238 msec in patients treated with eptifibatide and 593±344 msec in those without, p=0.7 (figure 8). Short (<600msec) diastolic deceleration time occurred in 6 (40%) of those treated with eptifibatide, compared to 12

Fig. 8. Histogram of diastolic deceleration time and pressure half time of LAD blood velocity

Patients treated with eptifibatide had higher diastolic velocities, 39±11 cm/sec, vs 31±9 cm/sec, p=0.043 and tended to have higher diastolic LAD flows, 49±26 ml/min, vs 35±17

Fig. 9. Histogram of diastolic and systolic velocities of LAD blood velocity profiles in

patients with and those without eptifibatide treatment.

profiles in patients with and those without eptifibatide treatment.

discharge was normal. In figure 7, an example of a patient with unfavorable LAD blood velocity profile after primary angioplasty and bare metal stent implantation in a patient with acute anterior STEMI. Short diastolic deceleration time (less than 600msec) and early systolic flow reversal are demonstrated. In this patient left ventricular ejection fraction was reduced at admission and did not improve later.

Fig. 6. Favourable LAD blood velocity profile with prolonged diastolic deceleration time and forward systolic flow.

Fig. 7. Unfavourable LAD blood velocity profile with reduced diastolic deceleration time and early systolic flow reversal.
