The FinnValve investigators planned a nationwide registry to investigate the early and late outcome of transcatheter aortic valve implantation (TAVI) compared to surgical aortic valve replacement (SAVR) in patients with aortic valve stenosis performed from 2008 to 2017 at five Finnish University Hospitals. Data will be collected in a dedicated electronic case report form.

Rationale of the study Uncertainty regarding the potential benefits of transcatheter aortic valve implantation (TAVI) compared to surgical aortic valve replacement (SAVR) in patients with aortic valve stenosis (AS) requires well-designed studies with long-term data on the outcome of these patients. A Finnish nationwide registry would allow complementing of the knowledge gained from randomized trials by providing data on the outcome of a more inclusive patient population, within a Health Care System that reflects the actual clinical practice in Scandinavia. In fact, the internal validity attained in randomized trials is often achieved at the expense of uncertainty about generalizability, especially since the populations enrolled in such studies may differ in significant ways from those seen in practice.

The choice among different surgical aortic valve prostheses is based on solid data with 20-year follow-up, which have shown significant risk of structural valve deterioration of bioprosthesis on the second decade after implantation. However, much less is known about the structural durability of TAVI prostheses beyond 3 years of follow-up. This nationwide registry would provide data on the durability of surgical bioprostheses as well as second and third generation TAVI prostheses at 7 years . Continuous follow-up of these patients will allow monitoring of the durability of these prostheses on the long run.

Furthermore, the introduction of TAVI prompted a rapid development of minimally invasive surgical techniques and rapid deployment surgical bioprostheses in order to reduce the risk of early adverse events after SAVR. However, it is unclear whether these advances have a real clinical benefit on the early and late outcome of patients undergoing SAVR.

Patients and Methods

Patients operated on for AS at each Finnish University Hospitals from January 2008 to September 2017 will included in to this registry. The following inclusion and exclusion criteria will be considered:

Inclusion criteria:

• Patients aged >18 years
• Primary aortic valve procedure with a bioprosthesis for AS with or without associated regurgitation.
• TAVI and SAVR with or without associated coronary revascularization
• TAVI and SAVR for AS after any prior major cardiac surgery with exception of any maze procedure and/or closure of the left atrial appendage.

Exclusion criteria:

• Patients who underwent any prior SAVR or TAVI
• Patients undergoing concomitant procedures on the mitral valve, tricuspid valve or the ascending aorta.
• Patients operated on for aortic valve endocarditis
• Patients operated for isolated aortic valve regurgitation.

Definition criteria for baseline and operative variables as well as early and late outcomes will be according to the Valve Academic Research Consortium (VARC) 2 guidelines (Kappetein et al. Eur J Cardiothorac Surg 2012;42:S45-60). Prosthetic valve structural deterioration and failure will be reported according to the last specific guidelines on this topic (Capodanno et al. Eur J Cardiothorac Surg. 2017;52:408-417). However, because of the lack of complete echocardiographic follow-up in these patients, valve structural valve deterioration will be classified only according to the definition criteria of severe hemodynamic structural valve deterioration of these guidelines.

The late events of interest are all-cause mortality, stroke, myocardial infarction, myocardial revascularization, structural deterioration, non-structural valve dysfunction, repeated procedures on the aortic valve and implantation of permanent pace-maker. Data on these late events will be collected at each participating center. These will be further checked and implemented for patients residing outside the catchment areas by interrogation of the Finnish National Health Institute for Health and Welfare database as well as Statistics Finland database.

Planned studies

The following is a tentatile of study projects which will be accomplished from the FinnValve registry:

1. Late outcome of TAVI versus SAVR in intermediate risk patients
2. Late outcome of TAVI versus SAVR in low risk patients
3. Late outcome of TAVI and SAVR in high risk patients
4. Futility of TAVI (3-month analysis)
5. Mini- versus full-sternotomy SAVR
6. Perceval sutureless bioprosthesis: 5-year outcome
7. Late outcome of sutureless versus conventional stented bioprosthesis in isolated SAVR
8. Late outcome of sutureless SAVR versus transfemoral TAVI in low- and intermediate risk patients
9. Early and late outcome of TAVI versus SAVR in patients with recent acute heart failure
10. Early and late outcome of TAVI versus SAVR in bicuspid AS
11. Early and late outcome of TAVI versus SAVR in obese patients (BMI >29) at low- and intermediate risk
12. Early and late outcome of isolated TAVI versus TAVI plus percutaneous coronary intervention (PCI) in patients with coronary artery disease
13. Early and late outcome of TAVI plus PCI versus SAVR plus coornary artery bypass grafting (CABG)
14. Prognostic impact of Syntax score on the early and late outcome after TAVI
15. Early and late outcome of TAVI vs. SAVR in patients with prior CABG
16. Early and late outcome of second versus third generation TAVI prostheses
17. Early and late outcome of transfemoral versus transaortic TAVI
18. Early and late outcome of trans-subclavian artery versus trans-aortic TAVI
19. Early and late outcome of sutureless versus conventional stented bioprosthesis in SAVR plus CABG
20. Early and late outcome of Trifecta versus Perimount bioprosthesis in isolated SAVR
21. Thromboembolic events after TAVI and SAVR
22. Early and late outcome of TAVI in nonagenarians
23. Prognostic impact of permanent pace-maker implantation on the early and late outcome after TAVI and SAVR
24. Prognostic impact of mild paravalvular leakage on the late outcome after SAVR
25. Impact of preoperative atrial fibrillation on the late outcome of TAVI
26. Impact of preoperative atrial fibrillation on the late outcome of SAVR
27. Early and late outcome of TAVI vs. SAVR in patients aged 85 years or older

Publications of results and PhD studies

The results of these studies will be published in international, peer-reviewed journals in the fields of cardiology and cardiac surgery. Furthermore, data from this registry will be available for several doctoral study projects. At this stage, a proposal for PhD studies has been submitted by:

1. Marko Virtanen, MD (Tampere University Hospital);
2. Pasi Maaranen, MD (Tampere University Hospital)
3. Maina Jalava, MD (Turku University Hospital);
4. Tuomas Ahvenvaara (Oulu University Hospital);
5. Teemu Laakso (Helsinki University Hospital).

Time schedule of data collection, checking and analysis

• December 2017: start of data collection
• End of April 2018: deadline for data collection
• End of May 2018: data checking
• June 2018-December 2019: analyses and writing of the planned studies.

Inclusion Criteria:

• Patients who underwent transcatheter (TAVI) or surgical aortic valve replacement (SAVR) for severe aortic valve stenosis
• Patients aged >18 years
• Primary aortic valve procedure with a bioprosthesis for AS with or without associated regurgitation.
• TAVI and SAVR with or without associated coronary revascularization
• TAVI and SAVR for AS after any prior major cardiac surgery with exception of any maze procedure and/or closure of the left atrial appendage.

Exclusion Criteria:

• Patients who underwent any prior SAVR or TAVI
• Patients undergoing concomitant procedures on the mitral valve, tricuspid valve or the ascending aorta.
• Patients operated on for aortic valve endocarditis
• Patients operated for isolated aortic valve regurgitation.

Patients who underwent transcatheter (TAVI) or surgical aortic valve replacement (SAVR) for severe aortic valve stenosis at five Finnish University Hospitals from January 2008 to September 2017