Screening for right-to-left shunts with contrast transcranial Doppler in hereditary hemorrhagic telangiectasia.

BACKGROUND AND PURPOSE Contrast transthoracic echocardiography (TTCE) is used to screen hereditary hemorrhagic telangiectasia (HHT) patients for right-to-left shunts (RLS) associated with increased stroke risk. We hypothesized that contrast transcranial Doppler (TCDc), shown to be highly sensitive for detecting RLS in patent foramen ovale, will be as comparable to TTCE for screening HHT patients. METHODS We compared TTCE and TCDc for detecting RLS in 12 patients with HHT who also underwent CT pulmonary studies to determine pulmonary arteriovenous malformation (PAVM) presence. The sensitivity and specificity of TTCE and TCDc in detecting PAVM were determined and the agreement between TTCE and TCDc in detecting RLS was assessed. RESULTS Both TTCE and TCDc had 100% sensitivity in detecting underlying PAVM; the specificity was 25% and 38%, respectively. The agreement in detecting RLS between TTCE and TCD was high (κ=0.76). TCD was well-tolerated with no immediate adverse or embolic events over the next 3 months. CONCLUSIONS TCDc offers a simple office-based alternative to TTCE for screening RLS associated with PAVM in HHT patients.