Acute Presentation of Normal Pressure Hydrocephalus After Transcatheter Aortic Valve Implantation: A Novel Interaction Between the First and Third Circulations.

BACKGROUND

Idiopathic normal pressure hydrocephalus (iNPH) negatively affects gait and cognition abilities and urine continence in the elderly. It is associated with systemic hypertension, although the exact pathophysiology is still unknown. A correlation to increased intracranial pulsatility and decreased compliance was suggested. Transcatheter aortic valve implantation (TAVI) is increasingly used in the treatment of severe AS. New-onset systemic hypertension affects some patients after TAVI.

OBJECTIVE

To identify any association between aortic valve replacement and the development of NPH.

METHODS

A cohort was created retrospectively of all patients who were evaluated for NPH with cerebrospinal fluid (CSF) tap test at a single institute during 2014-2019. Patients were reviewed for a past medical history of aortic valvular disease or aortic valve replacement.

RESULTS

A total of 242 patients underwent evaluations for NPH. Of these patients, 133 were considered to have iNPH. Six patients underwent aortic valve replacement before the initial symptoms of NPH: 1 surgical and 5 TAVI. The time from aortic valve replacement to the initial NPH symptoms was <6 months in 3 patients (as low as 1 month in 2 of them). Two patients had functional improvement after CSF tap test and proceeded to receive a shunt, 4 and 6 months after TAVI, respectively. Two patients developed hypertension after TAVI. Pulse pressure increased by >10 mm Hg in 3 patients after TAVI.

CONCLUSIONS

This is the first case series of symptomatic NPH after TAVI. In this unique subgroup, NPH symptoms can develop rapidly. Post-TAVI iNPH represents a novel interaction between the blood and CSF circulations.