Utility of right ventricular strain imaging in predicting pulmonary vascular resistance in patients with pulmonary hypertension.

Pulmonary vascular resistance (PVR) has important prognostic implications in the assessment of patients with pulmonary hypertension. Using echocardiography to measure PVR would have the advantage of being able to follow patients serially and to assess their response to treatment noninvasively. The authors sought to assess whether right ventricular strain rate imaging (SRI) can predict PVR in patients with pulmonary hypertension. The study population consisted of 46 patients referred for right heart catheterization. The inclusion criteria was mean pulmonary artery pressure ≥25 mm Hg in right heart catheterization in patients with pulmonary hypertension including chronic systolic heart failure. Echocardiography was performed to obtain SRI just before right heart catheterization. Mean values of peak systolic longitudinal strain and strain rate obtained from basal and mid-right ventricular free wall were calculated. The control group consisted of 35 healthy adults matched for age and sex. The most significant correlations were between basal right ventricular strain and strain rate (SR) and mean pulmonary arterial pressure (r=0.63, P=.000), transpulmonary gradient (r=0.6, P=.001), and PVR (r=0.5, P=.003). SR was independently correlated with PVR (PVR=26.9-16.9×basal right ventricular SR; r=0.53, P=.003). The present study shows that basal right ventricular free wall strain and SR could be independently correlated with PVR in patients with pulmonary hypertension.

Quantitative assessment of right atrial function by strain and strain rate imaging in patients with heart failure.

OBJECTIVES: We sought to evaluate the regional longitudinal strain/strain rate profiles in the right atrial wall to quantify right atrial function in systolic heart failure patients. BACKGROUND: According to previous studies on the deformational properties of the left atrium, the systolic strain and strain rates represent the atrial reservoir function and the early and late diastolic strain rates show the conduit and booster functions, respectively. METHODS: Thirty patients with a diagnosis of heart failure (left ventricular ejection fraction < or = 35%) scheduled for right heart catheterization were enrolled. Echocardiography was performed to obtain right atrial deformation indices just before the procedure. The control group consisted of 32 healthy adults matched for age and sex. The deformity indices obtained consisted of the right atrial peak systolic strain (RAS), right atrial peak systolic strain rate (RASSR), right atrial early diastolic strain rate (RAEDSR), and right atrial late diastolic strain rate (RALDSR). RESULTS: The right atrial deformation indices were significantly compromised in the heart failure patients versus the normal subjects (RAS: 68.5 +/- 53.9 vs 189.3 +/- 61.2, P = 0.000; RASSR: 2.9 +/- 1.9 vs. 5.3 +/- 1.5, P = 0.000).There was a significant correlation between the RAS and RASSR and cardiac output (RAS: r = 0.5, P = 0.005; RASSR: r = 0.5, P = 0.003), and cardiac index (RAS: r = 0.6, P = 0.001; RASSR: r = 0.6, P = 0.001). CONCLUSION: In light of our findings, we conclude that a diminished RA function, as assessed by strain imaging, plays a critical role in the pathophysiological process of heart failure patients.