Usefulness of right ventricular tissue Doppler imaging for diagnosis of right ventricular myocardial infarction.

Abstract

Right ventricular myocardial infarction (RVMI) is a complication of acute inferior myocardial infarction and sometimes causes severe hemodynamic disturbance. It is therefore important to promptly detect RVMI and assess the severity of right ventricular (RV) dysfunction. Tissue Doppler imaging (TDI) is a useful method to assess left ventricular function and RV function. In this study, we investigated the possibility of diagnosing RVMI using tricuspid annular velocity determined by TDI. Thirty consecutive patients with first acute inferior myocardial infarction were studied. The diagnosis of RVMI was based on an ST-segment elevation of at least 0.1mV in lead V4R. The patients were classified into 12 patients with RVMI (the RVMI group) and 18 patients without RVMI (non-RVMI group). All patients underwent two-dimensional echocardiography, pulsed Doppler and TDI, and coronary angiography within 48h after onset of myocardial infarction. Tricuspid inflow velocity was recorded by pulsed Doppler and early diastolic tricuspid inflow velocity (TVE) was measured. Peak early diastolic velocity of the tricuspid annulus (TVe') at the RV free wall was recorded using TDI. The ratio of TVE to TVe' (TVE/TVe') was calculated. TVe' was significantly lower in the RVMI group compared to that in the non-RVMI group (5.9±1.3 vs. 9.1±3.1; p=0.0025). On the basis of a TVe' cutoff value of less than 8.3cm/s, RVMI was diagnosed with 100% sensitivity and 61% specificity. The early diastolic tricuspid annular velocity determined by TDI is a noninvasive and sensitive index for diagnosing RVMI.