OBJECTIVE The aim of this study was to assess the natural history of paravalvular regurgitation at 1 year in patients undergoing TAVI. BACKGROUND The immediate incidence of paravalvular regurgitation is estimated to be between 65 and 85% following transcatheter aortic valve implantation (TAVI). There is limited data as to whether this deteriorates during follow-up. METHODS Forty-six patients were recruited from a TAVI programme at our institute. All patients underwent an assessment of prosthetic valve function periprocedurally with aortography and immediately postprocedurally with transthoracic echocardiography. Twenty-one patients with a median age was 83 (66-91) years of whom 14 were male reached 1 year follow-up, 13 of whom were available for repeat transthoracic echocardiography. RESULTS The incidence of paravalvular regurgitation immediately following TAVI was 86%. Of them 57% had < or = mild regurgitation and 29% had > mild regurgitation. At 1 year the incidence of paravalvular regurgitation was 77%. 54% had < or = mild regurgitation and 34% > mild regurgitation. No patient had severe regurgitation. The degree of regurgitation reduced in 6 (46%), stayed the same in 3 (23%), and increased in 4 (31%) of patients. CONCLUSIONS Patients undergoing TAVI have an immediate postprocedural risk of regurgitation of 86%. In the majority of cases the degree of paravalvular CoreValve regurgitation is mild, and remains stable in 70% of patients during medium term follow-up.