Author + information
- Guy Witberg1,
- Tali Steinmetz2,
- Avry Chagnac3,
- Heftziba Green3,
- Alexander Sagie4,
- Benaya Rozen-Zvi3 and
- Ran Kornowski5
Aortic stenosis (AS) is prevalent among chronic kidney disease (CKD) patients and is associated with reduced survival. Advanced CKD is a well established risk factor for worse prognosis post trans-catheter aortic valve replacement (TAVR), but there are no studies comparing outcomes of patients with CKD stage 3-5 treated conservatively, to those referred to TAVR.
A single center retrospective-cohort study that included all patients with both CKD stage 3-5 and severe AS who underwent TAVR or were treated conservatively between 2010-2015. we used several methods to adjust for baseline differences between the 2 groups: 1) Multivariate adjusted Cox proportional hazards ratio model 2) Propensity score matching 3) Inverse probability weighing based on the propensity score
The overall cohort included 260 patients (162 TAVR and 198 conservatively treated patients), mean age was 83.7 years, 43% of patients were male, mean valve area was 0.66 cm2 and mean gradient was 47 mmHg. The two groups were similar in terms of renal function and CKD stage. After a mean follow up of 1.9 years,mortality rate was 53/162 (32.7%) with TAVR vs 98/198 (49.5%) with conservative treatment (log rank p<0.001), after multivariate adjustment, conservative management was associated with a significant increase in the risk for mortality (HR=3.81, 95%CI 2.46-5.85 P<0.001).The area under the receiver operating characteristic curve for our propensity score model 0.78 (95% CI 0.73-0.83).Propensity score matched anlysis of 80 patient pairs with similar baseline chracteristics showed a significantly reduced mortality risk with TAVR for up to 5 year follow(27.5% vs 65% log rank p<0.001).Inverse probability wieghted adjusted analysis yielded similar results. At one year follow up, there was a significant decrease in renal function in the conservative management group (39.2 +/- 13.7 ml/min to 34.4 +/- 15.3 ml/min), but not in the TAVR group (43.2 +/- 11.5 ml/min to 42.8 +/- 14.5 ml/min) (P value = 0.001).
Our study suggests that in patients with CKD and severe AS, conservative management is associated with a dismal prognosis, while TAVR significantly improves short and medium-term survival. TAVR also results in preservation of renal function for up to 1 year follow up, as opposed to a significant decline in patients treated conservatively. These results should encourage both cardiologists and nephrologists to refrain from automatically excluding CKD patients from undergoing in depth assessment for TAVR eligibility. Further studies aimed at identifying characteristics of CKD patients that are associated with survival benefit following TAVR are needed, in order to improve clinical outcomes in this high risk patients population.
STRUCTURAL: Valvular Disease: Aortic