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Patients with advanced chronic kidney disease (CKD) who undergo transcatheter aortic valve replacement (TAVR) face increased risk of major bleeding as well as higher early and midterm mortality, according to a study published online May 5, 2014, ahead of print in the European Heart Journal. Moreover, the presence of atrial fibrillation (A-fib) or use of dialysis—and especially both—confers a poor prognosis, although in the absence of these factors, patients with advanced CKD reap quality-of-life benefits similar to TAVR patients with milder or no CKD.

Investigators led by Josep Rodés-Cabau, MD, of Laval University (Quebec City, Canada), evaluated 2,075 consecutive patients who underwent TAVR at 9 centers between January 2005 and June 2012. Patients were stratified into CKD stages according to baseline creatinine clearance. Advanced CKD was defined as:

• Stage 4 (15-29 mL/min/1.73 m²; n = 134)
• Stage 5 (< 15 mL/min/1.73 m²; n = 67, with 56 on dialysis)

Early Bleeding Risk Highlighted

At 30 days, the presence of stage 4 CKD was associated with a higher rate of stroke and major/life-threatening bleeding, while advanced CKD showed trends toward increased mortality and longer hospital stay (table 1).

 Table 1. Thirty-Day Outcomes

Advanced CKD was an independent predictor of 30-day major/life-threatening bleeding (OR 2.15; 95% CI 1.49-3.112; P = .001) and mortality (OR 1.80; 95% CI 1.07-3.03; P = .027), as well as late cumulative mortality (HR 1.72; 95% CI 1.33-2.21).

Patients with advanced CKD were also more likely to experience late all-cause mortality, driven mainly by increased cardiovascular mortality in stage 4 patients and noncardiovascular mortality in stage 5 patients. Noncardiovascular mortality was largely secondary to progression of kidney disease and bleeding events (table 2). 

Table 2. Cumulative Late Outcomes

Advanced CKD was an independent predictor of late cumulative mortality (HR 1.72; 95% CI 1.33-2.21).

Following TAVR, acute kidney injury (AKI) occurred in 348 patients (18.4%). Of these, 22 required dialysis. There was an association between the severity of preprocedure CKD and the occurrence of AKI, as well as the need for dialysis following TAVR (both P = .001). However, no differences in the amount of contrast media used was observed between patients with and without AKI (P = .639).

At 1 year, echocardiographic data (available for 79% of patients) showed no deterioration in valve hemodynamics (mean transvalvular gradient and mean valve area) over time across the CKD groups. Likewise, improvements in NYHA functional class were similar for all CKD groups.

On multivariable analysis, 2 factors predicted higher risk of late mortality:

• History of A-fib (adjusted HR 2.29; 95% CI 1.47-3.58)
• Dialysis therapy (adjusted HR 1.86; 95% CI 1.17-2.97)

One-year Kaplan-Meier rates of freedom from all-cause mortality were almost 80% for advanced CKD patients with neither A-fib nor dialysis or dialysis alone but fell to 59.3% for those with A-fib alone and to 29.2% for those with both factors (log rank P < .001). At 2-year follow-up, all CKD patients with both A-fib and dialysis had died.

According to the authors, patients with aortic stenosis undergoing TAVR frequently also have CAD, heart failure, and conduction disturbances, and the presence of CKD may worsen outcomes by exacerbating any or all of these comorbidities.

In addition, they note, advanced CKD has been linked to platelet dysfunction and hemostatic abnormalities, leading to increased bleeding risk, especially in patients on dual antiplatelet therapy or warfarin. “The present study showing… the major role of bleeding events in the poorer outcomes of such patients strongly suggests the advisability of avoiding antithrombotic overtreatment and the questionability of using systematic dual antiplatelet therapy in this challenging group.”

Presence of A-fib/Dialysis Should Prompt Reconsideration of Management

The current results also demonstrate that preexisting A-fib is associated with “an ominous prognosis” when it is combined with chronic dialysis, the authors observe. Therefore, they advise, elderly patients with aortic stenosis and both conditions “should be proposed for [TAVR] with extreme caution and after thorough evaluation by the heart team.” If accepted for the procedure, they should receive careful follow-up and probably adjustment of antithrombotic therapy. In fact, use of single antiplatelet therapy and other treatments such as percutaneous left atrial appendage closure should probably be considered in this high-risk group, they add.

On the other hand, Dr. Rodés-Cabau and colleagues say, contrary to previous data linking advanced CKD with decreased functional status and quality of life, the current study showed that patients who survived TAVR and remained alive at 1 year reaped as much functional benefit as the rest of the study population. “This highlights the fact that the procedure was not futile in a significant proportion of patients and increases the clinical relevance of better identifying those patients with advanced CKD who are likely to survive following a [TAVR] procedure,” they say.

Allende R, Webb JG, Munoz-Garcia AJ, et al. Advanced chronic kidney disease in patients undergoing transcatheter aortic valve implantation: insights on clinical outcomes and prognostic markers from a large cohort of patients. Eur Heart J. 2014;Epub ahead of print.

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