Brief history: A 32-year-old female presents with dysphagia, dizziness, and dysarthria.
Salient findings: Chest X-ray demonstrates many embolization coils within both lungs. Photographs demonstrate superficial telangiectasias of the tongue and distal phalanx. These findings indicate the patient’s diagnosis: hereditary hemorrhagic telangiectasia (HHT), previously known as Osler-Weber-Rendu syndrome.
Patient population/natural history of disease: HHT is an autosomal dominant trait, so family members should be counseled on the implications of having a relative with the disease. HHT patients have abnormal vessels prone to bleeding and often develop arteriovenous malformations (AVMs). Diagnosis is made with 75% of the following symptoms:
- Mucocutaneous telangiectasias;
- GI, pulmonary, or hepatic AVMs; and/or
- A first-degree relative with HHT.
Patients often present with dyspnea and hemoptysis. With pulmonary AVMs, the oxygenation and filtration functions of the lungs are bypassed, placing the patient at risk for hypoxia, polycythemia, paradoxical strokes, and brain abscesses.
Management: AVMs can be diagnosed and treated with angiography and embolization. In this patient the coils had been placed elsewhere. The use of coils larger than 3 mm in AVMs should be treated because they are associated with significantly increased morbidity and mortality. Steel coils are covered with thrombogenic fibers that induce clotting and sealing of the AVM; blood is no longer shunted through the right-to-left shunt. Unfortunately, a long-term complication of pulmonary AVMs treated by embolization therapy is the development of new pulmonary AVMs.
The patient in this case had many metallic coils visible on chest X-ray and because she had required multiple pulmonary angiograms and embolizations over the years.
It’s important to administer an ECG to all HHT patients prior to treatment; those with a left bundle branch block must have pacing mechanisms in place or at hand because catheter placement and manipulation within the right heart can induce right heart blockage. Take care to avoid air emboli in all lines due to right-to-left shunting in these patients.
- Untreated pulmonary AVMs are associated with paradoxical strokes, brain abscesses, and hypoxia;
- HHT is associated with pulmonary AVMs;
- Coil embolization of pulmonary AVMs has been shown to improve dyspnea and oxygen saturation while decreasing right-to-left shunt fraction in HHT patients.
- Complications of embolization therapy may include development of new pulmonary AVMs; and
- All patients should undergo ECG prior to pulmonary angiography to screen for left bundle branch block. TH
Helena Summers is a radiology resident and Erik Summers is a hospitalist at the Mayo Clinic College of Medicine, Rochester, Minn.
- Swanson KL, Prakash UB, Stanson AW. Pulmonary arteriovenous fistulas: Mayo Clinic experience, 1982-1997. Mayo Clin Proc. 1999 Jul;74(7):671-680.
- Cottin V, Plauchu H, Bayle JY, et al. Pulmonary arteriovenous malformations in patients with hereditary hemorrhagic telangiectasia. Am J Respir Crit Care Med. 2004 May 1;169(9):994-1000. Epub 2004 Jan 23.