Focus on the surgical approach to transcatheter aortic valve implantation: Complications, outcome, and preoperative risk adjustment

Bedside risk score for prediction of acute kidney injury after transcatheter aortic valve replacement

Background

Acute kidney injury (AKI) is a common post-transcatheter aortic valve replacement (TAVR) complication associated with a poor prognosis. We sought to create a risk calculator using information that would be available during the work-up period.

Methods

Data were obtained from a multicentre TAVR registry (n=1993) with cases from 1 January 2012 to 31 December 2015. We used logistic regression to create a risk calculator to predict AKI as defined by the Valve Academic Research Consortium Guidelines. We internally validated our risk calculator using bootstrapping, and evaluated model discrimination and calibration.

Results

A simple risk score was derived with six variables, including New York Heart Association functional classification class 4, non-femoral access site, valve-in-valve procedure, haemoglobin, creatinine clearance and weight in kilograms. The score was able to predict the absolute risk of AKI from 1% to 72%. The model showed good discrimination with c-statistic 0.713, with good agreement between predicted and observed AKI rates across quintiles of risk.

Conclusions

This is the first risk calculator to assess post-TAVR risk of AKI. We found that information known pre-procedurally can be used to predict AKI. This may allow for more informed decision-making as well as identifying high-risk patients.

Is TAVR Ready for the Global Aging Population?

The emergence of the global pandemic of chronic diseases necessitates critical assessment of interventions that can be targeted at both the individual and population levels. Among cardiovascular diseases, the increasing prevalence of valvular heart diseases such as aortic stenosis parallels the rising burden of atherosclerotic cardiovascular diseases. As an alternative to surgical aortic valve replacement, technological innovation has allowed development of minimally invasive transcatheter aortic valve replacement (TAVR). This review examines whether TAVR can be applicable in low-resource regions across the world. Although revolutionary, TAVR is currently complex and requires a "Heart Team" approach for optimized patient care. We propose the emergence of telemedicine networks, newer valve designs that allow implementation of minimal approaches, and the use of minimal numbers of specialists for adapting TAVR to settings where surgical backup is not available. With efforts to reduce resource utilization, these alternate strategies have the potential to affect implementation of TAVR globally.