Ten-year follow-up of a trancatheter double Corevalve aortic valve implantation

During the last decade, transcatheter aortic valve implantation (TAVI) for severe aortic stenosis has evolved as an alternative to surgical replacement in cases with high surgical risk.[1] However, long-term survival data are scarce and information about TAVI durability is lacking.[2] Hereby, we report the degeneration of the first TAVI performed in Northern Greece which happened to be a double implantation of a CoreValve device, 10 years later.

A 77-year-old female patient with heart failure was diagnosed with severe aortic stenosis (V_max = 5.18 m/s, mean pressure gradient (MPG) = 46 mmHg, aortic valve area (AVA) = 0.78 cm²) with preserved left ventricular ejection fraction. The patient was hypertensive, with moderate renal insufficiency and impaired mobility due to chronic neurological problems. The calculated log-EuroScore was 15% and the Heart Team decided to take advantage of the TAVI approach with the Corevalve device. In June 2008, the TAVI procedure was performed successfully with two CoreValve 26 devices, one deployed into the other due to the aortic displacement of the first valve. The flow to the coronary sinuses was maintained through the gap between the lower edge of the skirt of the first valve and the upper edge of the skirt of the second valve.

At 1-month follow-up, the patient was asymptomatic and the CoreValve was functioning well (V_max = 1.8 m/s, MPG = 6.5 mmHg, AVA = 1.6 cm²) with trivial paravalvular regurgitation. The echocardiographic follow-up at 1-, 2-, 3- and 7-years post-TAVI did not demonstrate any evidence of valve degeneration. At the 10-year follow-up, the patient was symptomatic and the transthoracic echocardiography revealed mild paravalvular leakage and for the first time the presence of transvalvular regurgitation. Transoesophageal echocardiography demonstrated moderate to severe transvalvular regurgitation (Figure 1, Video 1, 2), with sufficient opening (V_max = 2.7 m/s, MPG = 12.5 mmHg, AVA = 1.4 cm²). The N-terminal pro-hormone B-type natriuretic peptide (NT-pro-BNP) was elevated to 867 pg/mL compared to the NT-pro-BNP levels 1- and 2-years post-TAVI (204 pg/mL and 253 pg/mL, respectively). There was no evidence of thrombus on the CoreValve frames by echocardiography and aortography (Video 3). The patient was on aspirin 100 mg once daily and ramipril 5 mg once daily and remained on the same medications on follow-up.

Figure 1. Transoesophageal echocardiography 10-years post CoreValve transcatheter implantation.

(A & B): Mid-oesophageal view at 140° & at 50°, respectively, demonstrate moderate to severe transvalvular regurgitation (thick red arrow) and mild paravalvular leakage (thin red arrow); (C): deep transgastric view at 0° depicts the transvalvular regurgitation (thick red arrow); (D): pulse-wave Doppler at mid-oesophageal view of the descending thoracic aorta at 90° demonstrates holodiastolic flow reversal with end-diastolic velocity 0.18 m/s; (E): pulse and continuous wave Doppler suggest that CoreValve opening was sufficient: maximum velocity (Vmax) = 2.7 m/s, mean presMPG = 12.5 mmHg, AVA= 1.4 cm² with continuity equation; (F): LVOT diameter measured at mid-oesophageal view at 140° (for the continuity equation). AVA: aortic valve area; LVOT: left ventricular outflow tract; MPG: mean pressure gradient.

Data regarding long-term outcomes following TAVI with CoreValve prosthesis remain limited. From three different registries with a follow-up of no more than 5-years, cardiovascular mortality at 1-year was 12.5%, at 4-years 19% and 28% at 5-years.[2]^–[4]

The durability of transcatheter prosthesis is a crucial issue. Different reports suggest structural integrity of the valve over a period of at least four years with the initial paravalvular regurgitation improving over time.[5]^,[6] Moderate paravalvular leak was observed in 17.8%, 16.5%, and 10.1% of patients at 1, 2, and 3 years, respectively, improving over time.[3] At five years, transcatheter valves performance compares favourably with the surgical bioprostheses with signs of significant valve failure in only 1.4%.[2]

Our frail-old-patient was alive 10-years post CoreValve implantation, but the valve was degenerated based on the significant transvalvular regurgitation with no evidence of calcification or prolapsed of any leaflet. The NT-pro-BNP increase may be attributed to aortic regurgitation.[7] It is of note that despite the presence of the double metallic case, there was no evidence of thrombus and no compromise of coronary flow.

This report supports the durability and safety of the CoreValve implantation, even in a restricted high metal environment, in older patients, but also raises concern on the expanding use of the device in younger patients.