The Relationship Between Paroxysmal Vertigoes and Right-To-Left Shunt: A Large Observational Study

Background The association between paroxysmal vertigo and right-to-left shunt (RLS) is rarely reported. We investigated the incidence and correlation of RLS in patients with different paroxysmal vertigo diseases. Methods This large observational study included patients with paroxysmal vertigo from seven different hospitals in China from 2017 to 2021 (NCT04939922). Migraine patients within the same period were included for comparison. Demographic data and medical history were collected, contrast transthoracic echocardiography (cTTE) was performed, and the clinical features, dizziness handicap inventory, and incidence of RLS in each group were recorded. Results This study used a consecutive sampling of 4536 patients from seven centres, and a total of 2751 patients were enrolled. The proportion of RLS in patients with migraine with aura (MA), migraine without aura (MoA), vestibular migraine (VM) with headache, VM without headache, and benign recurrent vertigo (BRV) was significantly higher than that in patients with benign paroxysmal positional vertigo (BPPV), Meniere’s disease (MD), and vestibular paroxysmia (VP) (P<0.05). There was no statistical difference between the frequency of RLS in patients with BRV and those with MoA (P=0.931), MA (P=0.997), VM with migrainous headache (P=0.787), and VM without migrainous headache (P=0.754). There was a positive correlation between the RLS grade and the dizziness handicap inventory scores of VM and BRV patients (P<0.01). Conclusions RLS was significantly associated with BRV and VM. RLS may be involved in the pathogeneses of BRV and VM and may serve as a reference index for the differential diagnosis of central and peripheral vertigo. Trial registration: CHRS, NCT04939922, registered 14 June 2021- retrospectively registered, https://register.clinicaltrials.gov

Vascular Loops: The Innocent Bystander for Vestibular Paroxysmia

Introduction: Vestibular paroxysmia (VP) is a condition with recurrent short bouts of vertigo and is thought to be part of a neurovascular compression syndrome caused by the vascular loop. However, this is still being debated as vascular loops are considered as normal variants with limited studies involving vertiginous patients. Objectives: The aim of this paper is to study the association between audiovestibular symptoms and the presence of vascular loops and to study the association between vestibular paroxysmia and vascular loops. Design: This is a retrospective analysis of clinical, audiological and MRI findings of patients with and without vascular loops and vestibular paroxysmia from 2000 to 2020. Results: A total of 470 MRI Internal Auditory Meatus scans were performed during the study period of which, 71 (15.1%) had vascular loops and 162 (34.5%) had normal MRI which were used as controls. From the 233 subjects recruited, there were 37 subjects with VP and 196 non VP subjects were used as controls. There was no association between the vascular loop and control groups in terms of co-morbidity and audiovestibular symptoms. The VP group had a significantly older mean age of 51.8 (SD ± 10.3) as compared to the non VP group with the mean age of 45.6 (SD ± 15.5). The VP group had higher number of patients presenting with hearing loss at 97.3% when compared with those without VP (80.1%) ( P = .01). The odds of having a vascular loop giving rise to VP was not statistically significant at 0.82 (95% CI 0.3735-1.7989) P = .62. Conclusion: The vascular loop is a normal variant which may or may not give rise to audiovestibular symptoms or vestibular paroxysmia. Clinical assessment is still most important tool in deriving a diagnosis of VP and MRI may be useful to rule out other central causes.