Right-to-left shunt and idiopathic sudden sensorineural hearing loss

In the present retrospective cohort study, we investigated the association between idiopathic sudden sensorineural hearing loss (ISSNHL) and right-to-left shunt (RLS). For this study, we recruited 40 patients with ISSNHL treated in our department between January 2015 and January 2016. Inclusion criteria were: ≥ 18 years old, unilateral sensorineural hearing loss diagnosed within 2 weeks after onset, unknown cause, no previous surgery in the respective ear and no ？uctuation in hearing loss. All patients underwent a pure-tone audiogram and a trans-cranial Doppler ultrasonography (TCD) with contrast saline (c-TCD) and received hyperbaric oxygen (HBO) and concomitant steroid therapy. C-TCD examination detected the RLS in 20 patients (50%). ISSNHL patients with RLS were younger than those without RLS (p = 0.007). Vertigo was present mainly in the RLS group, while hypercholesterolaemia, arterial hypertension and hyperglycaemia were mainly seen in the “no RLS” group. The proportion of complete recovery was highest in the “No RLS” Group (40%), although it was not statistically significant. In conclusion, RLS is frequent in ISSNHL, particularly in young patients without comorbidities and with associated dizziness, who should routinely undergo TCD to exclude the presence of RLS. Unfortunately, TCD can only detect the RLS, and not the location of the shunt. This would be possible through transesophageal echocardiography (TEE) or intracardiac echocardiography (ICE), which are much more invasive than TCD, and require further study