A 79-year-old female patient was referred to our center due to severe aortic insufficiency after a previously implanted transcatheter aortic valve (TAVI). The patient's complex medical history included a bicuspid aortic valve with an aneurysm of the ascending aorta, which resulted in an acute type A aortic dissection in 1998. Following the dissection, emergency aortic valve reconstruction and a valve-sparing aortic root procedure (David procedure) were performed. In 2013, aortic stenosis and heart failure (HF) were diagnosed, both of which deteriorated during subsequent visits to the outpatient clinic. A Bentall procedure was a suboptimal therapeutic option due to the high procedural risk and the possibility of complications. TAVI was chosen as the intervention of choice in 2016, with planned oversizing due to the expected dilatation of the aortic root. An Evolut R 29 mm self-expanding valve was successfully inserted via a transfemoral approach with good expansion but low placement and minimal paravalvular leak seen after the procedure. Left bundle branch block (LBBB) developed after the first TAVI procedure. The patient was admitted again to a regional hospital shortly before referral to our center in 2021 due to worsening HF symptoms. Echocardiography confirmed a severely reduced ejection fraction (EF 20%) with concomitant severe aortic valve insufficiency resulting from a severe paravalvular leak. The patient was transferred to our center for further evaluation of possible treatment options (patient characteristics available in Supplementary S1, Timeline in Figure 1).

BMI 20.44 kg/m², BSA 1.38 m², afebrile, pulse rate of 75 bpm, respiratory rate of 21/min, and blood pressure of 112/65 mmHg. Blood oxygen saturation was normal without supplemental oxygen therapy. Lower extremity pretibial edema was present.

NT-pro BNP of 17,098 ng/L, creatinine 59 umol/L.

The ECG showed sinus rhythm with a left bundle branch block with a QRS width of 230 ms (Supplementary Figure S2).

Echocardiography revealed an enlarged left ventricle (EDD 6.4 cm, EDV 305 ml, EDVI 221 ml/m²) with mild wall hypertrophy (IVS 1.1 cm, inf-lat 1.4 cm) with severely reduced ejection fraction, a normal stroke volume (LVEF 22%, SV 70 ml), and severe valvular and paravalvular insufficiency of the Evolut R biological TAVI valve with mild mitral regurgitation. The central valvular insufficiency was caused by the degeneration of the right leaflet, which led to a diagnostic work-up and exclusion of infective endocarditis of the artificial valve—this was ruled out with transesophageal ultrasound (TEE), cardiac magnetic resonance imaging (MRI), and positron emission tomography (PET-CT) scans, in addition to serial blood cultures, which remained sterile. Echocardiographic signs of LV mechanical dyssynchrony were present. These findings were also confirmed by MRI. A CT of the thoracic and abdominal aorta revealed persistence of the ascending aortic aneurysm distal to the graft placement with dissection spanning the ascending aorta and aortic arch and terminating proximal to the aortic isthmus with involvement of the brachiocephalic trunk and progression of the aortic root dilatation compared to previous CT scans (Figure 2, Supplementary Figures S3, S4). Severe tortuosity of the iliac arteries was evident upon 3D reconstruction. Coronary angiography showed no significant atherosclerotic lesions. Infective endocarditis was excluded as the cause of the valve degeneration.

Due to the frailty of the patient and the high surgical risk, the cardiac team's consensus was to correct the valve regurgitation with a valve-in-valve TAVI using a Myval 26 mm (Meril, Gujarat, India) valve due to the appropriate size, the radial force achieved by balloon-expandable valves, and the shorter stent frame height of the valve, reducing the neo-skirt. Careful procedural planning was performed in order to assess the anatomical considerations of the slipped Evolut R valve and its relationship to the aortic root. A bifemoral approach was obtained by positioning a 16F transcatheter aortic valve introducer in the right femoral artery and a 6F introducer for a pigtail catheter in the left femoral artery. Due to the severe iliac artery tortuosity, a nitinol hydrophilic guide wire covered with polyurethane Radifocus ™guidewire M (Terumo, Tokyo, Japan) with RJ 4.0 6F support was used. A distal part “S-reshaped” J soft wire-mounted pigtail catheter was used to safely cross the dissected segment (Supplementary Figure S5). The aortic valve was then crossed with a straight tip soft wire using an Amplatz left (AL) 1 catheter (Launcher, Medtronic, Minnesota, USA). The soft wire was exchanged for an extra-stiff 0.0035” Lunderquist wire (Cook Medical, Indiana, USA). We then proceeded with the implantation of a 26 mm Myval valve, which was placed without predilation of the existing Evolut R (Supplementary Figure S6). The Myval valve was positioned at the level of the natural bicuspid aortic valve ring (10/90, outflow/aortic bulbus). Control selective coronary angiography showed good patency of the coronary arteries, and control aortography showed good alignment of the prosthetic valve with no residual aortic regurgitation (Figure 3).

Following valve-in-valve TAVI, intermittent complete AV block was recorded. As LBBB was already present after the first TAVI procedure in conjunction with severely reduced ejection fraction, resynchronization therapy was indicated. As an alternative to biventricular pacing, we opted for the LBBAP technique. A right atrial lead (Capsurefix MRI Surescan 52 cm, Medtronic) was temporarily inserted into the right ventricle (RV) to prevent potential asystole due to mechanical injury of the right bundle branch during LBBP lead positioning. As previously described (14–18), a 3,830 SelectSecure 69 cm lead (Medtronic) and a C315His (Medtronic) catheter were used for transseptal lead insertion. Selective left bundle branch capture with correction of the left bundle branch block was achieved (Supplementary Figures S5, S6). The right atrial lead was then positioned in the RA, and the atrioventricular delay was optimized to achieve the shortest QRS duration (Figure 4).

A post-procedural echocardiography did not show immediate improvement in left ventricular function with a residual dilatation of the left ventricle (EDV 333 ml, EDVI 247 ml/m²), severely reduced ejection fraction (EF 17%) with a normal stroke volume (SV 74 ml), elevated LV filling pressures, and moderate post-capillary pulmonary hypertension. The TAVI valve was well expanded with minimal trace paravalvular leakage. A Doppler ultrasound of the bifemoral puncture sites was performed before discharge due to a murmur, which did not reveal signs of fistulas or pseudoaneurysms.

Follow-up in the cardiology clinic revealed functional improvement in the patient with some residual exertional dyspnea but minimal signs of heart failure (NYHA class II). Follow-up echocardiography was also performed and showed improvement in LV function with an increase in ejection fraction (3D EF 27% as compared to 17% before discharge, Supplementary S7) with some minimal residual signs of mechanical dyssynchrony and normal filling pressures of the left ventricle, minimal paravalvular and central aortic regurgitation, and mild tricuspid regurgitation adjacent to the ventricular pacemaker lead with normal pulmonary pressures. Laboratory markers of HF also improved, with an NT-proBNP of 4,089 ng/L.