Poor Mobility Strongly Predicts Mortality in TAVR Patients
Poor mobility predicts worse short- and long-term survival in patients undergoing TAVR, according to a study published online June 29, 2015, ahead of print in Catheterization and Cardiovascular Interventions. Hence, mobility screening should be performed before selecting patients for the procedure, researchers suggest.
“The clinical ramifications are significant, given that mobility assessment is a straightforward, cheap, and quick measurement in the majority of cases, especially in relation to the multiple technical assessments that are required to identify suitable patients,” write David Hildick-Smith, MD, of the Brighton and Sussex University Hospitals NHS Trust (Brighton, England), and colleagues.
Using data from the UK TAVI Registry, the investigators analyzed 312 consecutive TAVR patients (mean age 81.2 years; 53.2% men) treated at their center between 2008 and 2014. Most patients (89%) were treated transfemorally with the CoreValve prosthesis (Medtronic). Mean Logistic EuroSCORE and STS score were 17.4 and 4.6, respectively.
The following frailty assessment tools were used either prospectively or retrospectively for all patients:
- EuroSCORE II (poor mobility was defined as severe impairment of mobility secondary to musculoskeletal or neurological dysfunction)
- Brighton Mobility Index
- NYHA Functional Classification
- Karnofsky Performance Scale
- Katz Index of Independence
- Canadian Study Health Association (CSHA) Clinical Frailty Scale
Other Measures No Substitute for Poor Mobility
Overall survival was 95.2% at 30 days and 74.7% at a maximum of 5.8 years (mean follow-up 2.2 years).
On univariate analysis, poor mobility as defined by EuroSCORE II was the only predictor of mortality at 30 days, while poor mobility as well as higher values for the Brighton Mobility Index and the CSHA Clinical Frailty Index each foretold higher likelihood of death over the long term (tables 1).
But on multivariate analysis, none of the frailty indices added to the predictive power of poor mobility. Moreover, there were no interactions between mobility and any of the other frailty measures regarding short- or long-term mortality.
Widening Risk Assessment
“To date, only a limited number of studies have tried to combine both medical and functional assessments to produce a more complete assessment of risk for elderly patients undergoing [TAVR],” Dr. Hildick-Smith and colleagues write.
While many risk scores are “suitable for assessing the functional status of octogenarians,” little research has been done to examine their relationship with mortality and morbidity, they say.
For example, EuroSCORE and STS are often used to evaluate TAVR candidates, but “evidence for their use is limited, [and they] were derived in younger adults than the [TAVR] cohort and were specifically for cardiac surgery,” the authors report. “Understanding the need for widening risk assessment to include mental and physical frailty is growing.”
Cockburn J, Singh MS, Rafi NHM, et al. Poor mobility predicts adverse outcome better than other frailty indices in patients undergoing transcatheter aortic valve implantation. Catheter Cardiovasc Interv. 2015;Epub ahead of print.
- Dr. Hildick-Smith reports serving as a proctor and adviser to Boston Scientific, Edwards Lifesciences, Medtronic, and St. Jude Medical.