Impact of sex-specific thresholds for low flow in assessment of prognosis in concordantly and discordantly graded aortic valve stenosis.

Aims Sex-specific low flow was recently defined as stroke volume index (SVi) ≤ 40 mL/m² in men and ≤32 mL/m² in women. We tested the prognostic association of these cut-offs in patients with aortic stenosis (AS) with concordantly and discordantly graded AS [concordantly graded AS by energy loss (CGAS_EL) and discordantly graded AS by energy loss (DGAS_EL)] based on pressure recovery adjusted aortic valve area [energy loss (EL)]. Methods and results Data from 1351 patients with asymptomatic AS, peak jet velocity <4 m/s, and preserved left ventricular ejection fraction enrolled in the Simvastatin and Ezetimibe in Aortic Stenosis study were used. DGAS_EL was defined as EL <1.0 cm² with mean aortic gradient <40 mmHg and CGAS_EL as EL ≥1.0 cm² with mean aortic gradient <40 mmHg. Patients were further grouped into normal and low flow. The outcome was combined all-cause death and hospitalization for heart failure (HF). CGAS_EL with normal/low flow was present in 915/253 patients, and DGAS_EL with normal/low flow was present in 57/126 patients. During a median follow-up of 4.3 years, event-free survival was lower in patients with DGAS_EL irrespective of flow compared to CGAS_EL with normal flow (P < 0.05). In Cox regression analysis, DGAS_EL with normal or low flow were both associated with increased risk of all-cause death and hospitalization for HF after adjustment for age, sex, heart rate, randomized study treatment, hypertension, aortic valve replacement, and aortic valve calcification (P < 0.05). No survival difference was found between patients with normal vs. low flow within groups of DGAS_EL or CGAS_EL. Conclusion Identification of low flow by the proposed sex-specific thresholds of SVi needs more prognostic validation before application in clinical practice. ClinicalTrials.gov identifier NCT00092677. [ABSTRACT FROM AUTHOR]