DETERMINANTS OF TRANSMITRAL INFLOW PATTERN 10-14 DAYS AFTER ACUTE MYOCARDIAL-INFARCTION

Aim: The administration of thrombolytic therapy after an acute myocard ial infarction can reduce the size of the infarct and improve left ven tricular function. We used pulsed Doppler to assess left ventricular d iastolic function after an acute myocardial infarction in patients tre ated with recombinant tissue plasminogen activator (rTPA). Patients an d methods: We studied 104 patients after an acute myocardial infarctio n, 48 treated with a placebo and 56 with rTPA. They were compared with 36 age-matched controls. The Doppler parameters measured included the early peak in diastoiic flow velocity, the peak during atrial contrac tion, the atrial:early ratio, mean deceleration, deceleration time, an d half-filling fraction. Doppler parameters for large and small infarc t sizes were compared. Results: The Doppler parameters did not differ between treatment groups. Compared with the normal controls, significa nt differences were observed in both treatment groups for the early pe ak (placebo P<0.05; rTPA P<0.001), the atrial:early ratio (placebo P<0 .05; rTPA P<0.01), and the half-filling fraction (P<0.001 for both). I n patients with large infarcts, the atrial peak was depressed (P=0.008 ). Multivarate analysis showed that end-diastiolic pressure, age, end- systolic volume, and regional wall motion parameters were major predic tors of Doppler parameters.