Impact of Trans-catheter Aortic Valve Implantation on Renal Function

Impact of Trans-catheter Aortic Valve Implantation on Kidney Response to Contrast Dye Administration: an Observational Registry

Both contrast-induced acute kidney injury (AKI) and pre-existing chronic kidney disease are associated with an increased mortality risk in patients requiring aortic valve replacement. Nonetheless, the direct haemodynamic impact of the aortic barrage (i.e. pre-renal mechanism) on renal function compromising and its reversibility in patients undergoing trans-catheter aortic valve implantation (TAVI) is unknown.

This registry aims to evaluate the effect of severe aortic stenosis removal on the risk of contrast-induced acute renal injury (CI-AKI) during TAVI procedures and on renal function evolution

All patients undergoing trans-catheter aortic valve implantation (TAVI) for severe aortic stenosis at Our Institution after the introduction of a standardized approach (2017 - TAVI lite technique) will be eligible for the study. To be enrolled in this registry, patients need to have performed both diagnostic preliminary exams (coronary angiography, percutaneous coronary intervention, or CT) and TAVI procedure in our hospital within maximal time lapse of two months. A complete renal function assessment after each contrast-based procedure (i.e. at least three measurements) is also an essential pre-requisite for enrolment.

Study design: ambispective registry. Estimated population size: 340 for the retrospective phase (based on annual TAVI procedure rate of ~150); 760 for the prospective phase (based on annual TAVI procedure rate of ~200) The incidence of contrast medium-induced acute kidney injury according to Kidney Disease Improving Global Outcomes (KDIGO) classification before and after the TAVI procedure will be the primary end-point of the study. The Incidence of 1-year mortality after TAVI procedure in patients with and without post-procedural CI-AKI will be the co-primary end-point.

Inclusion Criteria:

• Age >18 years with a life expectancy >1 year;
• Patient candidate for percutaneous aortic valve implantation after formal indication of our "Heart Team".
• Patient performed at least one contrast-based exam other than the TAVI procedure in the previous two months.
• Patients had adequate renal function assessment after each contrast medium administration (TAVI procedure included) with at least three post-procedural measurements in the following 5 days.
• Patients were informed of the possibility to be the object of anonymized data collection for study protocols approved by the internal Ethical Committee and had provided written informed consent to the procedure (for patients before 2018) or had provided written informed consent to the research purposes of IRCCS (for patients from 2018 to date).

Exclusion Criteria:

• Female with childbearing potential or lactating;
• Acute or chronic end-stage renal dysfunction defined as estimated glomerular filtration rate (eGFR) <30 mL/min/1.73m2);
• Candidate for dialysis treatment;
• Co-morbidities that could interfere with the completion of study procedures, or life expectancy of less than 1 year;
• Absent or incomplete renal function assessment after each contrast-based procedure;
• Participating in another investigational drug or device trial that has not completed the primary endpoint or would interfere with the endpoints of this study;