Several abnormalities in both right ventricular (RV) size and function tend to occur in patients with pulmonary hypertension (PAH). However, there is no data regarding the effect of PAH on RV free wall mechanical activation in these patients that can contribute to global dysfunction.
We studied several well-established echocardiographic parameters used to assess RV performance in a heterogeneous group of patients with varying degrees of PAH as well as in a group of healthy volunteers and then used tissue Doppler imaging (TDI) to investigate if abnormalities in RV free wall mechanical activation occur with RV dysfunction.
Prospective data collected in 20 patients with varying degrees of PAH (mean age 51 ± 13 years, WHO class average 2.8 and mean pulmonary systolic pressure 78 ± 24 mmHg) were compared to similar data retrospectively obtained from 20 healthy volunteers (mean age 45 ± 15 years). Patients with varying degrees of PAH had worse RV performance parameters than healthy volunteers (RV fractional area change 37 ± 13% versus 52 ± 5%, p <0.0001; RV myocardial performance index 0.76 ± 0.31 versus 0.29 ± 0.11, p <0.0001; and Eccentricity Index 1.41 ± 0.57 versus 0.98 ± 0.06, p<0.005). Similarly, in these patients with an abnormal RV performance, TDI showed a statistically significant lower peak longitudinal RV free wall strain (-21.5 ± 9.0% versus -28.0 ± 4.1%, p< 0.01) and a significantly delayed time-to-peak strain (459 ± 76 msec versus 388 ± 29 msec, p<0.0005) values than healthy volunteers; a very strong correlation between RV mechanical delay and RV fractional area change (r = -0.89) was noted.
RV free wall mechanical delay, as documented by TDI, was identified in patients with varying degrees of PAH. Furthermore, there is strong correlation between RV free wall mechanical delay and overall global RV performance in these patients.
This novel echocardiographic technique has the potential for identifying patients with subclinical RV dysfunction.
Angel Lopez-Candales, None.