Relationship between restrictive Doppler mitral inflow pattern and myocardial viability after a first acute myocardial infarction

Objective: This study was designed to evaluate the relation between restrictive Doppler mitral inflow pattern and echocardiographic indices of myocardial viability in patients with first acute myocardial infarction undergoing dobutamine stress echocardiography to determine the extent of infract zone viability. Methods: Fifty-six consecutive patients were studied 7. days after first ST-elevation acute myocardial infarction with high dose dobutamine stress echocardiography. A score model based on 16 segments and four grades was used to assess the left ventricular function. Viability was defined as an improvement in wall motion by at least one grade in two or more dysfunctional segments during any stage of the dobutamine infusion compared with the baseline. Pulsed-wave Doppler mitral inflow velocity was obtained at baseline (prior to dobutamine infusion) and restrictive pattern defined as E/A ratio ≥ 2 and E-wave deceleration time ≤ 140 ms. Results: Restrictive mitral inflow pattern was detected in 25 (45%) patients. Seventeen (68%) patients in restrictive group received thrombolytic therapy while 26 (84%) in the non-restrictive group received this therapy (P= 0.001). Viability in the infracted territory was detected in 17 (54%) out of 31 patients in non-restrictive group, while only 3 (12%) out of 25 patients in restrictive group showed evidence of contractile reserve (P= 0.0001). Conclusions: This study showed a strong association between restrictive Doppler mitral inflow pattern and lack of myocardial contractile reserve during dobutamine stress echocardiography in patients with a first acute myocardial infraction. © 2012.