Aortic Valve Gradient and Clinical Outcome in Patients Undergoing Transcatheter Aortic Valve Implantation for Severe Aortic Stenosis

Abstract

Objectives: To explore the relation between the baseline aortic valve gradient (AVG) as a continuous variable and clinical outcomes following transcatheter aortic valve implantation (TAVI) in general and specifically in patients with high-gradient aortic stenosis (AS). Methods: We reviewed 317 consecutive patients who underwent TAVI at our institution. We investigated the relation between AVG as a continuous/categorical variable and outcome among all patients and in patients without low-flow low-gradient AS, using the Cox proportional hazard model adjusting for multiple prognostic variables. Results: Patients had a peak AVG of 79.9 ± 22.8 mm Hg (mean 50.5 ±15.7). During a mean follow-up of 2.7 years, AVG was inversely associated with mortality and mortality or cardiac hospitalization. Every 10-mm-Hg increase in peak AVG was associated with 18% reduction in mortality (p = 0.003) and 19% reduction in mortality/cardiac hospitalization (p < 0.001). Every 10-mm-Hg increase in mean AVG was associated with a 24% reduction in both outcomes (p = 0.005 and p < 0.001). Subgroup analysis of patients with left-ventricular ejection fraction >40% or peak AVG >64 mm Hg yielded similar results. Conclusions: Mean and peak baseline AVGs are directly associated with improved outcomes after TAVI; AVG can be used to select the patients most likely to benefit from TAVI.

Prognostic significance of aortic valve gradient in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

“…Le Ven et al found that a decrease in AVG level was not associated with a significant increase in mortality after adjustment for multiple clinical variables among 639 severe AS patients (adjusted HR = 1.05, 95% CI 0.95–1.17, per 10 mm Hg decrease in mean AVG, P = 0.33) . Witberg et al analyzing data from one institution ( n = 317) reported an overall inverse association between AVG and post‐TAVR mortality (HR = 0.82, P = 0.003 per 10 mm Hg increase in mean AVG) .…”

“…Only a few trials evaluated the relationship between AVG as a continuous variable and mortality. Kodali et al investigated predictors of mortality post‐TAVR among 348 patients with severe AS, and found that every 10 mm Hg increment in mean AVG was associated with an adjusted 18% reduction in 2‐year mortality ( P = 0.003) .…”

“…Most [13][14][15][16][17], though not all [18][19][20], of these studies did show worse prognosis for low-gradient patients following. This issue seems to have been resolved by a recent publication of data from the TVT registry [12], the largest analysis of low-gradient vs high-gradient AS patients undergoing TAVR (n 5 11,292), showing that (1) although both reduced LVEF and low AVG are associated with higher rates of 1-year mortality and recurrent heart failure, after adjustment for other baseline factors, only AVG was found to be a significant predictor of clinical outcomes regardless of LVEF and (2) despite their worse prognosis, low-gradient AS patients still gain considerable benefit from TAVR.…”

“…Among patients undergoing SAVR, those with low‐gradient AS are known to have increased mortality risk . In patients undergoing TAVR, there is a controversy whether low‐gradient AS is associated with increased risk for overall mortality; several studies found low‐gradient AS to be associated with poor outcome , but other studies did not demonstrate this relationship . It should be noted that only a few studies evaluated AVG as a continuous variable, and only one study evaluated the prognostic impact of AVG as a continuous variable in patients with preserved LV function and high‐gradient AS, who constitute the vast majority of TAVR patients.…”