Sasaki Y, Kitagawa H, Ishihara K, Masegi T
Laboratory of Internal Medicine, Faculty of Agriculture, University of Gifu, Japan.
Nihon Juigaku Zasshi. 1990 Aug;52(4):743-52. doi: 10.1292/jvms1939.52.743.
Improvement of pulmonary arterial lesions after heartworm removal using flexible alligator forceps was investigated by measuring pulmonary arterial pressure (PAP), and by angiographic and histopathological examinations in 11 dogs. PAP obtained immediately after worm removal corresponded well with angiographic abnormalities. In 2 dogs, high PAP immediately after worm removal fell gradually by 12 weeks, and obstructions on angiogram were resolved at 4 to 12 weeks. In 4 dogs, slightly high PAP fell to the normal range at 4 weeks, and angiographic abnormalities were considerably reduced at 4 to 12 weeks. In 5 dogs, PAP returned to normal range immediately after worm removal, and angiographic changes almost disappeared at 4 to 8 weeks. On biopsy immediately after worm removal, samples of the main pulmonary arteries showed severe intimal proliferations with villous or papillary protrusion into the lumen. Autopsy at 12 to 20 weeks indicated that the intimal protrusions were remarkably reduced as compared with the biopsy samples in all cases. However, villous intimal protrusions were seen in the caudal lobar arteries in cases with remaining alive worms. New vessels seemed to develop into thromboemboli with time. From these findings, it is clear that the pulmonary arterial lesions improved after heartworm removal, and the clinical signs disappeared following the improvement in hemodynamics. Aspirin therapy (5 mg/kg/day) for 4 weeks after worm removal in 5 dogs did not improve the intimal lesions as compared to 3 control dogs.
通过测量肺动脉压（PAP）以及对11只犬进行血管造影和组织病理学检查，研究了使用弹性鳄鱼钳摘除心丝虫后肺动脉病变的改善情况。摘除心丝虫后立即测得的PAP与血管造影异常情况相符。2只犬在摘除心丝虫后立即出现的高PAP在12周时逐渐下降，血管造影显示的阻塞在4至12周时得到缓解。4只犬在4周时略高的PAP降至正常范围，血管造影异常在4至12周时显著减轻。5只犬在摘除心丝虫后PAP立即恢复到正常范围，血管造影变化在4至8周时几乎消失。在摘除心丝虫后立即进行活检，主肺动脉样本显示严重的内膜增生，有绒毛状或乳头状突入管腔。在12至20周时进行尸检表明，与活检样本相比，所有病例的内膜突出均明显减少。然而，在有存活心丝虫的病例中，尾叶动脉可见绒毛状内膜突出。随着时间的推移，新血管似乎发展为血栓栓塞。从这些发现可以清楚地看出，摘除心丝虫后肺动脉病变有所改善，并且随着血流动力学的改善临床症状消失。与3只对照犬相比，5只犬在摘除心丝虫后进行4周的阿司匹林治疗（5毫克/千克/天）并未改善内膜病变。
