A 22-year-old male patient, who had been diagnosed with AR due to BAV at 11 years of age, was admitted to our hospital. Although he was asymptomatic, his last echocardiography had shown worsening left ventricular ejection fraction (LVEF) by 54% and left ventricular (LV) dilatation (LV end-diastolic/systolic diameter [LVDd/LVDs], 63.9 mm/45.6 mm). Furthermore, the left and right coronary cusps were fused (Fig. 1A), and the fused cusp was severely prolapsed (Fig. 1B). The eccentric aortic regurgitant jet was striking the anterior mitral leaflet and the vena contracta was 6.4 mm, leading to the diagnosis of severe AR (Fig. 1B). Computed tomography showed that the sinus of Valsalva was dilated to 41.0 mm, and the diameters of the ventriculoaortic and sinotubular junctions were 31.0 and 28.3 mm, respectively. Therefore, we concluded that the aortic root dilatation and prolapse of the fused cusp caused severe AR.
The patient underwent AVP and valve-sparing aortic root replacement (reimplantation technique) via a median full sternotomy. After the aortic valve was exposed through a transverse aortotomy under cardiopulmonary bypass, the right and left coronary cusps were fused and severely prolapsed (geometric height: 20, 22, and 26 mm for the left, right, and non-coronary cusp, respectively). The diameter of the Brussel’s height was 24 mm, and the ventriculoaortic junction was 25 mm. Each coronary cusp was almost equal in size with a commissural orientation of nearly 120°, which is classified as the very asymmetrical bicuspid aortic valve with fusion of right and left coronary cusps [1, 2] (Fig. 2A). After applying the first row of sutures to a Gelweave Valsalva Ante-Flo Gelatin Impregnated Woven Dacron Graft 26-mm (Terumo Vascutek, Tokyo, Japan), a horizontal mattress suture using 5–0 Nespilene (Alfresa Holding Corporation, Tokyo, Japan) was placed at the free margin of the raphe. We decided the ideal height of the neo-commissure based on the height of other commissures, and the ends of the sutures were passed outside the prosthetic graft at the level of the sinotubular junction (neo-commissure reconstruction) (Fig. 2B). After neo-commissure reconstruction and placement of the second row of sutures, the original non-coronary cusp became prolapsed compared to the neo-left and right coronary cusps because the non-coronary cusp leaflet was larger than the other cusp leaflets (effective height: 8, 8, and 3 mm for the left, right, and non-coronary cusps, respectively) (Fig. 2C, D). Therefore, double-row continuous mattress sutures were applied in and out of the free margin of the non-coronary cusp leaflet with 7–0 Gore-Tex (W. L. Gore and Associates, Inc., Flagstaff, AZ) suture, and the tension of this suture was adjusted to equally correct the effective height of each cusp (free margin resuspension) (Additional file 1). Finally, the left and right coronary arteries were anastomosed to the prosthetic graft using the Carrel patch technique, and a distal anastomosis was performed between the prosthetic graft and the ascending aorta.
The patient’s postoperative course was uneventful. The echocardiography showed that LV dilatation had improved (LVDd: 54.0 mm; LVDs: 32.3 mm), and LVEF increased to 65.0%. Moreover, the effective height was sufficiently improved (8.7, 9.0, and 8.8 mm for the left, right, and non-coronary cusp, respectively). Mild regurgitation occurred at the neo-commissure, and the vena contracta of the AR jet was 1.0 mm, which was classified as mild AR (Fig. 3). The patient was discharged 12 days postoperatively without any complications. At present, 1.5 years after the surgery, the patient is well, and no progressive regurgitation or decreased left ventricular diameter was observed on the follow-up echocardiography.