FRANCE 2 Registry Yields Early Mortality Risk Score for TAVR

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Patient-specific variables such as low body mass, significant comorbidities, and transapical or other non-femoral approach help predict early mortality after transcatheter aortic valve replacement (TAVR), according to a study published online April 16, 2014, ahead of print in Heart. A prognostic score could be used to aid in decision making, though it may not be as reliable in those with very high levels of risk.

Using data from the French Aortic National CoreValve and Edwards (FRANCE 2) registry, researchers led by Bernard Iung, MD, of Bichat Hospital (Paris, France), divided 3,833 consecutive patients into 2 cohorts; the first 2,552 patients were used to develop the prognostic score of 30-day or in-hospital mortality following TAVR (developmental cohort), and the remaining 1,281 patients were used for validation purposes.

All FRANCE 2 patients underwent TAVR between January 1, 2010 and December 31, 2011, with either the balloon-expandable Sapien or Sapien XT prostheses (Edwards Lifesciences; Irvine, CA), or the self-expandable CoreValve device (Medtronic; Minneapolis, MN).

Low Body Mass, Comorbidities Predict Early Mortality

Overall, in-hospital and 30-day mortality was 10.0% (9.9% in the developmental cohort and 10.1% in the validation cohort). The multivariate model identified a number of predictive factors useful for determining early mortality risk:

  • Age ≥ 90 years
  • Body mass index < 30 kg/m2
  • New York Heart Association class IV
  • Pulmonary hypertension
  • Critical hemodynamic state
  • Two or more pulmonary edemas in the previous year
  • Respiratory insufficiency
  • Dialysis
  • Transapical or other (eg, transaortic and transcarotid) approaches

Each of these factors was assigned a point value to arrive at a 21-point prognostic score.

Each risk factor showed varying magnitudes of effect on early mortality in the cohort. Among the most important factors were critical hemodynamic state, low body mass, respiratory insufficiency, dialysis, and transapical approach (table 1).

Table 1. Predictors of Early Mortality after TAVR

 

Adjusted OR (95% CI)

P Value

Score

Critical Statea

2.39 (1.42 to 4.02)

.001

3

Low Body Mass, ≤18.5 kg/m2

2.27 (1.09 to 4.74)

.03

3

Respiratory Insufficiency

1.64 (1.22 to 2.20)

.001

2

Dialysis

2.88 (1.46 to 5.66)

.002

4

Transapical Approach

2.02 (1.47 to 2.78)

< .0001

2

Other Non-femoral Approach

2.18 (1.11 to 4.28)

.02

3

aDefined as any of a number of situations including ventricular tachycardia, preoperative cardiac massage, preoperative acute renal failure, and others.  

In the development cohort, scores ranged between 0 and 14 per patient out of a total of 21. The score achieved what the authors called a “moderate discrimination” with a c-index of 0.67 in the developmental cohort and 0.59 in the validation cohort. Each 1 point increase in score was associated with an OR increase of 1.33 (95% CI 1.25-1.40).

Risk Score Useful but Limitations Noted

“By definition, all candidates for TAVR are at high risk,” Dr. Iung said in an email with TCTMD. “My opinion is that this score should be used as an aid to decision making. In particular, we do not propose in the paper a threshold above which TAVR should not be performed.” He noted that the c-index suggests the score may not work as well at very high levels of risk.

The score could theoretically range from 0 to 21, but no patient had a risk score above 14, suggesting that extremely high-risk candidates were denied the procedure. Dr. Iung said none of the variables determined to be important predictors of early mortality were unexpected with the possible exception of lower body mass. He did note that this finding has been seen in other surgical series as well and could be an indicator of frailty.

Anita Asgar, MD, of the Montreal Heart Institute (Montreal, Canada), said in an email with TCTMD that while the score highlights some of the key clinical issues that need to be considered in patient selection, it may have limited utility in daily practice.

“The limitations of the score include its limited applicability to discriminate between patients given its weak c-index,” she said. “Given the data presented, it is unlikely to replace the multi-disciplinary team decision,… [but] it is an important step in the direction of developing tools to better serve our patients.”

Additional Parameters Suggested

In an accompanying editorial, Henrique B. Ribeiro, MD, and Josep Rodés-Cabau, MD, both of Laval University (Quebec City, Canada), say including frailty and functional parameters could improve the prognostic score. Further, limiting the scope of the score to 30-day mortality may miss some patients, they add. For example, in the FRANCE 2 registry, although 10% of patients died within 30 days, 14% died within the first year. Extending the score’s scope for period of risk,  adding frailty and functional parameters, and possibly adding futility outcomes (ie, lack of improvement in quality of life) should help improve patient selection and consequently outcomes with TAVR, they explain.

“All this should translate into improved patient selection for TAVR, which in turn should be associated with both improved outcomes and a better cost-effectiveness ratio,” they write.

 


Sources:

1.      Iung B, Laouénan C, Himbert D, et al. Predictive factors of early mortality after transcatheter aortic valve implantation: individual risk assessment using a simple score. Heart. 2014;Epub ahead of print.

2.        Ribeiro HB, Rodés-Cabau J. The multiparametric FRANCE-2 risk score: one step further in improving the clinical decision-making process in transcatheter aortic valve implantation. Heart. 2014;Epub ahead of print.

 

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FRANCE 2 Registry Yields Early Mortality Risk Score for TAVR

Patient-specific variables such as low body mass, significant comorbidities, and transapical or other non-femoral approach help predict early mortality after transcatheter aortic valve replacement (TAVR), according to a study published online April 16, 2014, ahead of print in Heart
Disclosures
  • The FRANCE 2 registry was funded by Edwards Lifesciences and Medtronic.
  • Dr. Iung reports receiving consultant fees from Abbott, Bayer, Boehringer Ingelheim, and Valtech and receiving speaker’s fees from Edwards Lifesciences.
  • Dr. Asgar reports serving as a proctor for Medtronic CoreValve.
  • Dr. Rodés-Cabau reports serving as a consultant for Edwards LifeSciences and St. Jude Medical.

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