Objective: With tissue Doppler imaging and right ventricular Tei index, right ventricular function in patients with right ventricular myocardial infarction (RVMI) was assessed.
Method: 51 patients admitted to coronary care units and diagnosed as acute inferior myocardial infarction were further studied with the ECG criterion of ST segment elevation >or= 1mm in V(4R) to establish the diagnosis of RVMI. 23 patients were thus diagnosed as RVMI and 28 patients not. 20 healthy subjects served as controls. Clinical and echocardiography index were recorded. Peak systolic and peak early and late diastolic velocities (Sm, Em, Am) and Em/Am were acquired from the apical four-chamber view at the lateralside of tricuspid annulus, the septal side of the tricuspid annulus and the RV free mid-wall using DTI. Interval between tricuspid closing and reopening and ejection time (ET) from parasternal short-axis view were recorded by pulse-wave Doppler. RV Tei index was calculated.
Results: Sm and Em at the lateral side of tricuspid annulus and the RV free mid-wall reduced significantly in patients with RVMI as compared with those without RVMI and healthy individuals (Sm at the lateral (7.0 +/- 2.0) cm/s vs (8.7 +/- 1.9) cm/s and (10.6 +/- 2.1) cm/s, P < 0.01; Em at the lateral (6.3 +/- 1.9) cm/s vs (7.9 +/- 1.8) cm/s and (9.6 +/- 1.9) cm/s, P < 0.01; Sm at the RV free mid-wall (6.4 +/- 1.9) cm/s vs (8.0 +/- 1.9) cm/s and (9.4 +/- 2.0) cm/s, P < 0.05; Em at the RV free mid-wall (6.1 +/- 2.0) cm/s vs (7.6 +/- 2.0) cm/s and (9.2 +/- 2.3) cm/s, P < 0.05). RV Tei index in patients with RVMI also increased as compared with that in the other two groups (0.65 +/- 0.19 vs 0.40 +/- 0.15 and 0.26 +/- 0.10; P < 0.01).
Conclusions: The evaluation of velocities at the lateral side of tricuspid annulus and the RV free mid-wall using DTI and RV Tei index provides a noninvasive and rapid method for assessing right ventricular function in patients with RVMI.