TY - JOUR
T1 - Paradoxical low-flow aortic stenosis is defined by increased ventricular hydraulic load and reduced longitudinal strain
AU - Holmes, Anthony A.
AU - Taub, Cynthia C.
AU - Garcia, Mario J.
AU - Shan, Jian
AU - Slovut, David P.
N1 - Publisher Copyright:
© 2017 Italian Federation of Cardiology. All rights reserved.
PY - 2017
Y1 - 2017
N2 - Aims Patients with paradoxical low-flow severe aortic stenosis (PLF-AS) reportedly have higher left ventricular hydraulic load and more systolic strain dysfunction than patients with normal-flow aortic stenosis. This study investigates the relationship of systolic loading and strain to PLF-AS to further define its pathophysiology. Methods One hundred and twenty patients (age 79 ± 12 years, 37% men) with an indexed aortic valve area (AVAi) of 0.6 cm2/m2 or less and an ejection fraction of 50% or higher were divided into two groups based on indexed stroke volume (SVi): PLF-AS, SVi < - 35 ml/m2, N = 46; normal-flow aortic stenosis, SVi > 35 ml/m2, N = 74). Valvular and arterial load were assessed using multiple measurements, and strain was assessed using speckletracking echocardiography. Results Patients with PLF-AS were found to have more valvular load (lower AVAi, P = 0.028; lower energy loss coefficient, P = 0.001), more arterial load [decreased arterial compliance and increased systemic vascular resistance (SVR), both P < 0.001] and more total hydraulic load [increased valvuloarterial impedance (Zva), P < 0.001]. Transvalvular gradients and arterial pressures were similar. Longitudinal strain was lower in PLF-AS (P< 0.001), but circumferential and rotation strains were similar. On adjusted regression, AVAi, SVR and longitudinal strain were associated with PLF-AS [odds ratio (OR) = 1.34, P = 0.043; OR = 1.31, P = 0.004; OR = 1.34, P = 0.011, respectively]. When SVR and AVAi were replaced with Zva, longitudinal strain and Zva (OR = 1.38, P = 0.015; OR = 1.33, P < 0.001 for both, respectively) were associated with PLF-AS. Conclusion Increased hydraulic load, from more severe valvular stenosis and increased vascular resistance, and longitudinal strain impairment are associated with PLF-AS and their interplay is likely fundamental to its pathophysiology.
AB - Aims Patients with paradoxical low-flow severe aortic stenosis (PLF-AS) reportedly have higher left ventricular hydraulic load and more systolic strain dysfunction than patients with normal-flow aortic stenosis. This study investigates the relationship of systolic loading and strain to PLF-AS to further define its pathophysiology. Methods One hundred and twenty patients (age 79 ± 12 years, 37% men) with an indexed aortic valve area (AVAi) of 0.6 cm2/m2 or less and an ejection fraction of 50% or higher were divided into two groups based on indexed stroke volume (SVi): PLF-AS, SVi < - 35 ml/m2, N = 46; normal-flow aortic stenosis, SVi > 35 ml/m2, N = 74). Valvular and arterial load were assessed using multiple measurements, and strain was assessed using speckletracking echocardiography. Results Patients with PLF-AS were found to have more valvular load (lower AVAi, P = 0.028; lower energy loss coefficient, P = 0.001), more arterial load [decreased arterial compliance and increased systemic vascular resistance (SVR), both P < 0.001] and more total hydraulic load [increased valvuloarterial impedance (Zva), P < 0.001]. Transvalvular gradients and arterial pressures were similar. Longitudinal strain was lower in PLF-AS (P< 0.001), but circumferential and rotation strains were similar. On adjusted regression, AVAi, SVR and longitudinal strain were associated with PLF-AS [odds ratio (OR) = 1.34, P = 0.043; OR = 1.31, P = 0.004; OR = 1.34, P = 0.011, respectively]. When SVR and AVAi were replaced with Zva, longitudinal strain and Zva (OR = 1.38, P = 0.015; OR = 1.33, P < 0.001 for both, respectively) were associated with PLF-AS. Conclusion Increased hydraulic load, from more severe valvular stenosis and increased vascular resistance, and longitudinal strain impairment are associated with PLF-AS and their interplay is likely fundamental to its pathophysiology.
KW - Hydraulic load
KW - Longitudinal strain
KW - Paradoxical low flow
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U2 - 10.2459/JCM.0000000000000324
DO - 10.2459/JCM.0000000000000324
M3 - Article
C2 - 26556444
AN - SCOPUS:84946600072
SN - 1558-2027
VL - 18
SP - 87
EP - 95
JO - Journal of Cardiovascular Medicine
JF - Journal of Cardiovascular Medicine
IS - 2
ER -