“Pure” severe aortic stenosis without concomitant valvular heart diseases: echocardiographic and pathophysiological features

Abstract

Purpose In echocardiography the severity of aortic stenosis (AS) is defined by effective orifice area (EOA), mean pressure gradient (mPGAV) and transvalvular flow velocity (maxVAV). The hypothesis of the present study was to confirm the pathophysiological presence of combined left ventricular hypertrophy (LVH), diastolic dysfunction (DD) and pulmonary artery hypertension (PAH) in patients with “pure” severe AS. Methods and Results Patients (n = 306) with asymptomatic (n = 133) and symptomatic (n = 173) “pure” severe AS (mean age 78 ± 9.5 years) defined by indexed EOA < 0.6 cm2 were enrolled between 2014 and 2016. AS patients were divided into 4 subgroups according to mPGAV and indexed left ventricular stroke volume: low flow (LF) low gradient (LG)-AS (n = 133), normal flow (NF) LG-AS (n = 91), LF high gradient (HG)-AS (n = 21) and NFHG-AS (n = 61). Patients with “pure” severe AS showed mean mPGAV of 31.7 ± 9.1 mmHg and mean maxVAV of 3.8 ± 0.6 m/s. Only 131 of 306 patients (43%) exhibited mPGAV > 40 mmHg and maxVAV > 4 m/s documenting incongruencies of the AS severity assessment by Doppler echocardiography. LVH was documented in 81%, DD in 76% and PAH in 80% of AS patients. 54% of “pure” AS patients exhibited all three alterations. Ranges of mPGAV and maxVAV were higher in patients with all three alterations compared to patients with less than three. 224 (73%) patients presented LG-conditions and 82 (27%) HG-conditions. LVH was predominant in NF-AS (p = 0.014) and PAH in LFHG-AS (p = 0.014). Patients’ treatment was retrospectively assessed (surgery: n = 100, TAVI: n = 48, optimal medical treatment: n = 156). Conclusion In patients with “pure” AS according to current guidelines the presence of combined LVH, DD and PAH as accepted pathophysiological sequelae of severe AS cannot be confirmed. Probably, the detection of these secondary cardiac alterations might improve the diagnostic algorithm to avoid overestimation of AS severity.

Severe Aortic Valve Stenosis and Pulmonary Hypertension: A Systematic Review of Non-Invasive Ways of Risk Stratification, Especially in Patients Undergoing Transcatheter Aortic Valve Replacement

“…In particular, severe PH defined by sPAP ≥ 60 mmHg [42,43] or TRV ≥ 3.5 m/s [44] was an independent predictor of significantly faster patient demise in most studies. In a study that distinguished AS in terms of flow and gradient, the highest proportion of PH was seen in patients with high gradient [45].…”

Left ventricular hypertrophy, diastolic dysfunction and right ventricular load predict outcome in moderate aortic stenosis

“…A progressive narrowing of the aortic valve leads to a chronic increase of LV pressures resulting in concentric LVH. Concentric LVH induces a shift of the diastolic pressurevolume relationship followed by increasing DD with an increase of left ventricular end-diastolic filling pressure (LVEDP) which favors the development of post-capillary pulmonary severe AS without at least one of these pathophysiological changes is highly unlikely (10). In moderate AS, the presence of all three echocardiographic findings was only found in 18%, whereas none of those changes were found in at least 20% confirming that changes in LVMi, E/e' , and TR Vmax correlate with AS progression.…”

Rationale echokardiografische Funktionsdiagnostik

“…transvalvuläre Gradient (ΔPmean AS ) die weiteren Grundpfeiler der echokardiografischen AS-Diagnostik. Merke Die Diagnose einer hochgradigen AS kann zusätzlich durch die typischen Folgeerscheinungen bestätigt werden [11].…”

“…Die Diagnose einer hochgradigen AS kann zusätzlich durch die typischen Folgeerscheinungen bestätigt werden 11 .…”