Family screening in patients with isolated bicuspid aortic valve in a general hospital, yield and subgroup analysis

Abstract

Abstract Background Bicuspid aortic valve (BAV) may frequently lead to aortic dilatation with risk of aortic dissection. In patients with BAV both familial clustering and aortic dilatation in first-degree relatives (FDR) without BAV has been demonstrated. Based on these findings the ESC Aortic Guidelines recommend to consider screening of FDR, while the ACC/AHA Guidelines on Valvular Heart Diseases consider screening of FDR only if the index patient has associated aortopathy. Currently, no data about the effectiveness of screening is available. Purpose To investigate the yield of screening FDR of patients with isolated BAV and to explore subgroups with FDR of patients who had needed surgery or of patients with aortic dilatation. We hypothesized that aortic dilatation (>40mm) in the index patient is not a risk factor for BAV in FDR. Methods From 2012, patients with BAV visiting the outpatient clinic of a teaching hospital, received information advising cardiac screening of FDR. FDR of patients with isolated BAV who were referred, were included. From the 10 index patients from other hospitals, information was retrieved. [Fig.1] Results Referred were FDR from 118 index patients (mean age 60 years, standard deviation [SD] 14, range 15–90 years, 82 males [70%]). Of all index patients 63 (53%) had undergone aortic valve replacement, including concomitant ascending aorta replacement in 25 (21%). In the non-operated index patients, 31 (26%) had dilatation (>40mm) of sinus of Valsalva and/or tubular ascending aorta. Screened were 257 FDR (median 2 per index patient) comprising 20 parents (8%), 103 siblings (40%) and 134 offspring (52%). Mean age of FDR was 48 years (SD16, range 4–83 years) and 89 subjects (42%) were male. The diagnostic imaging modality was echocardiography in 240 cases (93%) and MRI in 17 cases. Ten FDR had an already known BAV and were not included in the screening. Among the 257 FDR, we diagnosed 12 new BAV (4.7%, 95% confidence interval [CI]2.9–8.0%) (mean age 44 years, 50% male). Additionally, we diagnosed 23 new isolated aorta dilatations (8.9%; 95% CI 6.0–13%) at level of sinus of Valsalva and/or tubular ascending aorta (mean age 57 years, 18 [78%] were male) [Fig. 1]. Among them, 11 had hypertension. FDR (n=147) of index patients with BAV and previous aortic valve surgery (n=63), had a risk ratio (RR) of 2.25 (95% CI 0.62–8.10) of having a BAV. FDR (n=126) of index patients with BAV and repaired or unrepaired aortic dilatation (n=56) had RR 0.35 (95% CI 0.10–1.25) of having a BAV. Conclusions Screening FDR of patients with isolated BAV resulted in a reasonable yield of 14% new cases with BAV or isolated aortic dilatation. The RR of the subgroup with aorta dilatation did not justify the limitation of the FDR as suggested in the ACC/AHA Guidelines. Figure 1. Flowchart of screening and result Funding Acknowledgement Type of funding source: None