Intravascular ultrasound imaging of the pulmonary arteries in primary pulmonary hypertension.

OBJECTIVE: Intravascular ultrasound has the unique ability to provide cross-sectional images of the arterial wall. This study examined intravascular ultrasound (IVUS) images of the proximal pulmonary arteries in primary pulmonary hypertension (PPH). METHODOLOGY: Study 1: Specimens from four patients who had died of PPH (in vitro PPH group) were compared with those of three patients who had died of subarachnoid haemorrhage but had no evidence of cardiopulmonary disease (in vitro control group). Three-centimetre segments of the following levels were examined by IVUS: pulmonary trunk, eight secondary branch arteries of the upper, middle, and lower lobes of both lungs, and the thoracic descending aorta. Study 2: Four patients with PPH (in vivo PPH group) and five patients without pulmonary hypertension and no evidence of cardiopulmonary disease (in vivo control group) were examined. The IVUS images of the apical segmental artery of the right upper lobe and the descending branch of the right pulmonary artery were studied. RESULTS: Echographic examination of formalin-fixed preparations of secondary branch sections of the pulmonary artery failed to show a clear three-layer structure in the in vitro control group (24 preparations), but a distinct three-layer structure and increased vessel wall thickness were observed in the in vitro PPH group (32 preparations). Similar findings were obtained in the in vivo study. The mean echo density of the proximal pulmonary arterial wall correlated well with the mean pulmonary arterial pressure (mPA) in the in vitro PPH, and also correlated with the mPA in the in vivo study (r = 0.960, P < 0.0001). The echo intensity of secondary branch sections of the pulmonary artery was higher in the in vitro PPH group than in the in vitro control group (180.5 +/- 27.0 vs 132.5 +/- 26.7 counts, P < 0.001); similar results were obtained in the in vivo study (144.7 +/- 23.4 vs 85.0 +/- 14.3 counts, P < 0.01). CONCLUSIONS: These results suggest that the histological changes detected in the pulmonary artery walls in the PPH group were responsible for the increased echo intensity.

Suppressive effect of sarpogrelate hydrochloride on respiratory failure and right ventricular failure with pulmonary hypertension in patients with systemic sclerosis.

We evaluated the effect of 12 months of 300-mg oral sarpogrelate hydrochloride (SH) once daily on the symptoms of Raynaud's phenomenon, respiratory failure and cardiac function in seven patients with systemic sclerosis. Arterial blood gases, pulmonary function, mean pulmonary arterial pressure, left ventricular ejection fraction (LVEF), right ventricular ejection fraction (RVEF), white blood cell count, C-reactive protein and the plasma concentrations of fibrinopeptide A, beta-thromboglobulin, platelet factor 4 and thrombomodulin were evaluated before and 2 and 12 months after SH administration. After 2 and 12 months of SH administration, a significant decrease was found in the frequency and duration of Raynaud's phenomenon, as well as the coldness, numbness and pain of Raynaud's phenomenon. Respiratory failure, as estimated by Hugh-Jones classification, was significantly decreased, whereas the percentage carbon monoxide diffusion capacity was significantly increased. The mean pulmonary arterial pressure decreased significantly, as did plasma fibrinopeptide A, beta-thromboglobulin and platelet factor 4. There was no significant change in LVEF after 2 or 12 months, but after 12 months of SH administration, RVEF increased significantly. In conclusion, use of SH may prevent Raynaud's phenomenon, respiratory failure and right ventricular failure in patients with systemic sclerosis.