Embolization of pulmonary AVMs of feeding arteries less than 3 mm: reports of two cases and an 8-year follow-up without embolization
The first case report concerns a 40-year-old woman with hereditary hemorrhagic telangiectasia (HHT). Her father died from a probable cerebral attack. At screening of families with HHT the patient was discovered with PAVMs eight years previously. PaO2 was then 9.7 kPa (72.8 mmHg), the contrast echocardiography showed a shunt of grade 4 (maximal), and the shunt was estimated to 24%. One big simple PAVM and two small PAVMs were visualized by pulmonary angiography (Fig. a and b). The big PAVM in right middle lobe was embolized with one detachable silicone balloon (Target Therapeutics, Fremont, CA, USA) (Fig. ) while the two small ones were left untreated because of small feeders <3 mm.\nAt follow-up 3 months later the PaO2 had increased to 13.0 kPa (97.5 mmHg), the oxygenation was 98%, the contrast echocardiography shunt had decreased to 3, and the shunt was estimated to 7%. The patient felt better performance. In the following years there were no occurring problems, especially no neurologic events, but the patient experienced periodic headaches.\nAt follow-up 8 years later the CT scan showed that the big PAVM was occluded with a residual scar at the place of the former PAVM. At pulmonary angiography the balloon was invisible, but the embolized PAVM was without flow. The feeders of the other two PAVMs had since the initial pulmonary angiogram 8 years earlier grown from 1.6 mm to 2.7 mm (right lower lobe) (Fig. ) and from 1.5 mm to 2.0 mm (left upper lobe) (Fig. a). The right sided PAVM was embolized using two vortexes – 35, 3–5 mm, 0.035 coils (Boston Scientific/Target Vascular, La Garenne-Colombes, Cedex, France) (Fig. b and c), and the left with one 3/30 mm coil (MR eye, non-ferro-magnetic standard embolization coil 0.035, Cook, Bjaeverskov, Denmark) (Fig. b).