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Summary Background:Angioplasty of an infarct related artery (IRA) performed several weeks or months after myocardial infarction (MI) may improve myocardial function. Hypothesis: We hypothesized that, as Doppler myocardial imaging (DMI) allows for the quantitative assessment of the systolic movement of myocardial segments, it may be a sensitive method for assessing changes in regional myocardial contraction and contractile reserve pre and post angioplasty of the IRA. Methods:In all, 39 patients (30 men, mean age 53.4 ± 8.3 years), 1 to 6 months after MI, who qualified for IRA angioplasty on the basis of myocardial viability in the infarcted zone as demonstrated by dobutamine stress echocardiography, were included in the study. Peak regional myocardial systolic velocities (S wave) of the infarcted segments were measured at rest and during low-dose dobutamine infusion (15 µg/kg/min) 1 day before angioplasty (Exam 1), 2 to 5 days (Exam 2), and 30 days (Exam 3) after successful angioplasty. The long-axis movement of the mitral annulus and of the basal and medial segments of the posterior (20 patients), anterior (17 patients), and lateral walls (2 patients) was evaluated. Results: At rest, S-wave velocity of the infarcted segments increased between Exams 1 and 2, without further improvement between Exams 2 and 3 (4.9 ± 1.2 vs. 5.6 ± 1.3 cm/s, p < 0.05 and 5.6 ± 1.3 vs. 5.5 ± 1.3 cm/s, NS, respectively). However, S-wave velocities measured during low-dose dobutamine infusion differed significantly both between Exams 1 and 2, and 2 and 3 (7.0 ± 1.5 vs. 7.8 ± 1.8 cm/s; p < 0.01; 7.8 ± 1.8 vs. 8.5 ± 1.6 cm/s; p < 0.05). Conclusions:Resting contractility at an infarct zone demonstrated rapid initial improvement after angioplasty of the IRA with no further change, whereas contractile reserve improved not only immediately after angioplasty but also during the next month.

Background: The Tei index of myocardial performance (IMP), which combines parameters of both systolic and diastolic ventricular function, is a useful prognostic factor in many clinical settings. Hypothesis: This study assessed the long-term prognostic value of IMP in patients discharged from hospital after acute myocardial infarction (AMI). Methods: Doppler/echocardiographic studies were recorded in 90 consecutive patients on Day 14 ± 2 following an AMI. The IMP was calculated from the Doppler recordings, as a sum of isovolumetric contraction time and isovolumetric relaxation time, divided by the ejection time. Results: The patients were followed for an average (SD) of 57.8 (16.1) months. During this period there were 22 (24%) cardiac events, defined as cardiac deaths (10) or Nonfatal recurrent myocardial infarctions (12). After multivariate Cox analysis, Tei index > 0.55 (relative risk [RR] 4.45; 95% confidence interval [CI] 1.28-15.45; p = 0.019), LV end-systolic volume > 65 ml (RR 3.23; 95% CI 1.34-7.79; p = 0.009), and mitral E wave deceleration time ⩽ 0.145 s (RR 2.94; 95% CI 1.24-6.92; p = 0.014) were the only independent predictors of cardiac events during the follow-up period. In a subgroup of patients with preserved LV systolic function (ejection fraction > 0.40), IMP was the only predictor of cardiac events (RR 6.37; 95% CI 1.32-30.77, p = 0.02). Conclusions: The Tei index of myocardial performance, which is simple and easy to calculate, is a useful tool for risk assessment in patients following myocardial infarction, and in a subgroup of patients with Normal or only mildly impaired systolic function.