Low-Flow Aortic Stenosis in Asymptomatic PatientsValvular–Arterial Impedance and Systolic Function From the SEAS Substudy
Dana Cramariuc, MD*, ,*,
Giovanni Cioffi, MD ,
Åshild E. Rieck, MD*,
Richard B. Devereux, MD ,
Eva M. Staal, MD, PhD||,
Simon Ray, MD¶,
Kristian Wachtell, MD, PhD#,
Eva Gerdts, MD, PhD*,
* Institute of Medicine, University of Bergen, Bergen, Norway
Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
Department of Cardiology, Cura Villa Bianca Hospital, Trento, Italy
Division of Cardiology, Weill Cornell Medical College, New York, New York
|| Department of Cardiology, Stavanger University Hospital, Stavanger, Norway
¶ Department of Cardiology, South Manchester University Hospital, Manchester, United Kingdom
# Department of Cardiology, The Heart Center, Rigshospitalet, Copenhagen, Denmark
* Reprint requests and correspondence: Dr. Dana Cramariuc, Department of Heart Disease, Haukeland University Hospital, NO-5021 Bergen, Norway (Email: dana.cramariuc{at}helse-bergen.no).
Objectives: This study sought to assess the impact of valvuloarterial impedance on left ventricular (LV) myocardial systolic function in asymptomatic aortic valve stenosis (AS).
Background: In atherosclerotic AS, LV global load consists of combined valvular and arterial resistance to LV ejection. Global load significantly impacts LV ejection fraction (EF) in symptomatic AS, but less is known about its effect on LV myocardial function in asymptomatic AS.
Methods: Echocardiograms in 1,591 patients with asymptomatic AS (67 ± 10 years, 51% hypertensive) at baseline in the SEAS (Simvastatin Ezetimibe in Aortic Stenosis) study evaluating placebo-controlled combined simvastatin and ezetimibe treatment in AS were used to assess LV global load as valvuloarterial impedance and LV myocardial function as stress-corrected midwall shortening. The study population was divided into tertiles of global load. Stress-corrected midwall shortening was considered low if <87% in men and<90% in women. Low-flow AS was defined as stroke volume index <22 ml/m2.04.
Results: Energy loss index decreased (0.85 cm2/m2 vs. 0.77 and 0.75 cm2/m2) and the prevalence of low stress-corrected midwall shortening increased (10% vs. 26% and 63%) with increasing LV global load (all p < 0.001). The EF was low in only 2% of patients. Patients with low-flow AS had higher LV global load and more often low midwall shortening than those with normal-flow AS (9.66 ± 2.23 mm Hg/ml·m2.04 and 77%, vs. 6.38 ± 2.04 mm Hg/ml·m2.04 and 30%, respectively, p < 0.001). In logistic regression analysis, LV global load was a main predictor of low stress-corrected midwall shortening independent of male sex, concentric LV geometry, LV hypertrophy (all p < 0.001), concomitant hypertension, and aortic regurgitation.
Conclusions: LV global load impacts LV myocardial function in asymptomatic AS independent of other main covariates of LV systolic function. LV myocardial systolic dysfunction is common in asymptomatic AS in particular in patients with low-flow AS and increased valvuloarterial afterload, whereas EF is generally preserved. (An Investigational Drug on Clinical Outcomes in Patients With Aortic Stenosis [Narrowing of the Major Blood Vessel of the Heart]; NCT00092677)
Key Words: echocardiography hemodynamics stenosis valves ventricles
|
Abbreviations and Acronyms
| | AS = aortic stenosis | | CI = confidence interval | | EF = ejection fraction | | LV = left ventricle | | ROC = receiver-operator characteristic |
|
Related Article
-
Aortic Stenosis: Look Globally, Think Globally
- Philippe Pibarot and Jean G. Dumesnil
J. Am. Coll. Cardiol. Img. 2009 2: 400-403.
[Full Text]
[PDF]
This article has been cited by other articles:

|
 |

|
 |
 
Z. Hachicha, J. G. Dumesnil, and P. Pibarot
Usefulness of the valvuloarterial impedance to predict adverse outcome in asymptomatic aortic stenosis.
J. Am. Coll. Cardiol.,
September 8, 2009;
54(11):
1003 - 1011.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. G. Dumesnil, P. Pibarot, and B. Carabello
Paradoxical low flow and/or low gradient severe aortic stenosis despite preserved left ventricular ejection fraction: implications for diagnosis and treatment
Eur. Heart J.,
September 8, 2009;
(2009)
ehp361v1.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
P. Pibarot and J. G. Dumesnil
Aortic Stenosis: Look Globally, Think Globally
J. Am. Coll. Cardiol. Img.,
April 1, 2009;
2(4):
400 - 403.
[Full Text]
[PDF]
|
 |
|
|