PURPOSE: Management of acute pulmonary embolism (PE) frequently depends on assessment of right ventricular (RV) function (Fx) by various qualitative measures on echocardiogram, with current quantitative methods limited by image quality and complex RV geometry. Measurement of the tricuspid annular plane systolic excursion (TAPSE) has been shown to correlate with RV ejection fraction (EF) by radionuclide testing. The RV performance index (RVPI) is a quantitative measure of RV Fx, independent of changes in preload and afterload. Neither has been assessed in patients with acute PE.
METHODS: Transthoracic echocardiograms from patients with acute PE who were enrolled in a prospective risk stratification study were reviewed. TAPSE and RVPI were compared to lab and echo parameters previously shown to correlate with morbidity and mortality in acute PE. Labs were drawn immediately after enrolment, and echocardiograms were performed within 24 hours of diagnosis and interpreted by a single, blinded cardiologist.
RESULTS: 28 patients had echocardiograms performed. RV Fx was normal in 18, mildly depressed in 6, and moderately depressed in 4. BNP was elevated in 5 patients (> 500 pg/mL) as was Troponin T (> 0.04 ng/ml). The TAPSE was significantly decreased when BNP was elevated (p = 0.009), and showed a significant correlation with right ventricular end diastolic diameter (RVEDD) (R2=0.34; p=0.003), and RV Fx (R2=0.39; p=0.006). There was a non-significant relationship to septal flattening (p=0.08). RVPI correlated significantly with RVEDD (R2=0.36; p=0.002) and RV Fx (R2=0.44; p=0.002), and was significantly increased in the presence of septal flattening (p=0.009).
CONCLUSION: Accurate assessment of RV function allows proper risk stratification in acute PE. TASPE and RVPI are easily obtained, quantitative measures that correlate significantly with lab and echo parameters that have proven to predict outcomes in this patient population.
CLINICAL IMPLICATIONS: When poor image quality precludes qualitative evaluation of the RV, the TAPSE and RVPI may be used to help estimate function. These parameters need to be correlated to clinical outcomes to prove their utility.
DISCLOSURE: Aaron Holley, None.