We studied whether (SVi) is a high-risk marker in high gradient aortic stenosis patients and whether SVi is related to other clinical factors contributing to this risk.
699 consecutive patients who underwent TAVI were screened, and only patients with high gradient aortic stenosis were included. A 35 ml/m2 cut-off for SVi was used to define patients with high versus low flow. The primary endpoint was defined as a combination of cardiovascular death and re-admission to hospital with heart failure at 30 days.
Of the 390 patients with high gradient severe aortic stenosis, 168 (43%) had low flow. They had higher NTproBNP [2578 (1043-5480) vs. 1714 (821-3599) ng/L, P=0.005], and smaller indexed valve area [0.28 (0.23-0.36) vs. 0.35 (0.29-0.42) cm2/m2, P< 0.001]. The primary endpoint was significantly more frequent in low flow compared to high flow patients [8.92% vs. 3.60%, HR 2.54 (95% CI 1.08 to 5.98), P=0.034] (Figure). This was driven mainly by a higher incidence of cardiovascular death [7 (4.2% vs. 0(0%), P= 0.003].
Previous myocardial infarction, CAD, AF, LV impairment, logistic Euroscore, in addition, to low flow were all predictors of 30 days clinical outcomes in an unadjusted model. When all these factors were included in the same adjusted model, only low flow appear to be a predictor of clinical outcomes (HR 2.43, 95% CI 0.86 to 6.64, P= 0.08), although this did not reach statistical significance (Table).
SVi can further characterise patients with high gradient aortic stenosis and may help to identify those who are at increased risk following TAVI.