Shun-Yi Hsu a, Chih-Jen Liu a, Shan-Hung Chang b, Hsin-Hua Chou a
aDepartment of Cardiology, Buddhist Tzu Chi General Hospital, Taipei Branch, Taipei, Taiwan
bSecond Section of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan
Impaired right ventricular (RV) diastolic function in hypertensive patients has been observed with pulsed wave tissue Doppler imaging (TDI). However, it is unclear whether TDI should be used to assess RV diastolic function for all hypertensive patients, regardless of their transtricuspid flow patterns. Moreover, the predictors of TDI-derived RV diastolic function abnormality in these patients are not well known.
Materials and Methods
Thirty untreated hypertensive patients underwent standard Doppler echocardiography and pulsed wave TDI. They were divided into two groups based on RV diastolic filling patterns: group A (n = 22) with a transtricuspid flow early diastolic filling velocity (E)/late diastolic filling velocity (A) ratio of > 1 and group B (n = 8) with a transtricuspid flow E/A ratio of < 1. Systolic and diastolic indices of both ventricles were compared between the two groups.
There were no significant differences in the baseline characteristics and standard Doppler echocardiographic measurements between the two study groups. Among the TDI parameters compared, only the RV regional relaxation time (RTm) was significantly longer in group B than in group A (50.4 ± 33.1 ms vs. 20.8 ± 22.0 ms, respectively; p = 0.009). A similar proportion of patients with TDI-derived RV diastolic dysfunction was observed in both groups (86.4% in group A vs. 87.5% in group B; p = 1.000). Stepwise, forward multivariate analysis revealed that the only independent correlate of TDI-derived indices of RV diastolic function was the transmitral flow E/A ratio. This ratio was positively correlated with the ratio of tricuspid annular peak early diastolic (Em) to late diastolic (Am) velocity and negatively correlated with RV RTm (p < 0.01 for both).
In this study, the transmitral flow peak E/A ratio showed the best correlation with TDI-derived RV diastolic function indices. Assessment of RV diastolic function using pulsed-wave TDI in hypertensive patients is valuable if an inverted transmitral flow E/A ratio is detected with conventional Doppler echocardiography.
Hypertension; Right ventricular diastolic function; Tissue Doppler imaging