Non-invasive determination of pulmonary hypertension with dynamic contrast-enhanced computed tomography: a pilot study.

OBJECTIVES

In this pilot study we explored whether contrast-material bolus propagation time and speed in the pulmonary arteries (PAs) determined by dynamic contrast-enhanced computed tomography (DCE-CT) can distinguish between patients with and without pulmonary hypertension (PH).

METHODS

Twenty-three patients (18 with and 5 without PH) were examined with a DCE-CT sequence following their diagnostic or follow-up right-sided heart catheterisation (RHC). X-ray attenuation over time curves were recorded for regions of interest in the main, right and left PA and fitted with a spline fit. Contrast material bolus propagation speeds and time differences between the peak concentrations were compared with haemodynamic parameters from RHC.

RESULTS

Bolus speed correlated (ρ = -0.55) with mean pulmonary arterial pressure (mPAP) and showed a good discriminative power between patients with and without PH (cut-off speed 317 mm/s; sensitivity 100%/specificity 100%). Additionally, time differences between peaks correlated with mPAP (ρ = 0.64 and 0.49 for right and left PA, respectively) and discrimination was achieved with sensitivity 100%/specificity 100% (cut-off time 0.15 s) and sensitivity 93 %/specificity 80% (cut-off time 0.45 s), respectively.

CONCLUSIONS

Bolus propagation speed and time differences between contrast material peaks in the PA can identify PH. This method could be used to confirm the indication for RHC in patients screened for pulmonary hypertension.

KEY POINTS

• Dynamic contrast-enhanced computed tomography (CT) can identify patients with pulmonary hypertension. • Bolus propagation speed in the pulmonary artery is reduced in pulmonary hypertension. • Peak-contrast propagation times provide a practical surrogate for speed. • This non-invasive technique could serve as a screening method for pulmonary hypertension. • Invasive right-sided heart catheterisations might be restricted to a smaller group of patients.