Background: Echocardiographic right ventricular (RV) function assessment is difficult and still a gray area despite rapid advancement of imaging modalities. The aim of this study is to assess the role of echocardiographic RV outflow tract (RVOT) function in the form of RVOT fractional shortening (RVOT FS) and RVOT systolic excursion (RVOT SE) for the assessment of RV function.
Methods: We studied ninety individuals divided equally into two groups. The control group included 45 normal healthy individuals and age-matched patient group included 45 patients with RV dysfunction which was defined by tricuspid annular plane systolic excursion (TAPSE) <16 mm and RV fractional area change (RV FAC) ≤35%. Echocardiography was performed to measure RVOT FS and RVOT SE and correlate them with other parameters of RV function including TAPSE, RV FAC, peak systolic velocity of the lateral tricuspid annulus (S') using pulsed tissue Doppler, and pulmonary acceleration time (PAcT).
Results: RVOT FS showed positive correlation with TAPSE (r = 0.75, P = 0.02), RV FAC (r = 0.45, P = 0.003), and PAcT (r = 0.39, P = 0.00) and negative correlation with left atrial dimensions (LADs) (r = -0.359, P = 0.017) and left ventricular end-diastolic dimensions (r = -0.304, P = 0.042). RVOT FS <32% was 93% sensitive and 98% specific to identify patients with impaired RV function. However, RVOT SE showed weak correlation with echocardiographic RV parameters. RVOT SE <5 mm was 80% sensitive and 76% specific to identify patients with impaired RV function.
Conclusion: RVOT FS is a simple valuable parameter that can be used for the assessment of RV function. However, RVOT SE is less accurate than RVOT FS in RV function assessment.
Keywords: Echocardiography; right ventricle; right ventricular outflow tract.