Ankush Sachdeva*, Biswajit Paul , Neel Bhatia , Vivek Kumar

CURRENT ISSUE•JULY 2013•VOL. 61 SPECIAL ISSUE : COMMUNITY-ACQUIRED PNEUMONIA

Correspondence

Low Gradient Severe Aortic Stenosis with Normal Ejection Fraction

Ankush Sachdeva*, Biswajit Paul**, Neel Bhatia***, Vivek Kumar****

*Attending Cardiologist, **Consultant Cardiologist, ***Attending Cardiologist, ****Principal Consultant Cardiologist, Fortis Escorts Heart Institute, Okhla, New Delhi.
Received: 06.08.2012; Accepted: 30.08.2012

Sir,

Low gradient severe aortic stenosis (LGSAS) with normal or preserved left ventricular ejection fraction(LVEF) is still not very well understood and a debatable entity. The data put forward by the retrospective studies has shown that these subset of patients carry a very poor prognosis.1,2

Currently this entity is defined by a mean gradient of ≤ 4o mm Hg (peak velocity ≤ 4m/s) across the stenotic valve and a valve area of < 1cm2 on echocardiography .The various clinical settings in which this can occur is systemic hypertension, a smaller LV size as per body surface area of the patient leading to a lower stroke volume, mildly lower LVEF of 50%, underestimation of valve area by Doppler because of underestimation of left ventricular outflow tract diameter (LVOT) and misalignment of Doppler sample volume. Also there has been an internal inconsistency in defining severe aortic stenosis by current guidelines relating to cut offs of valve area in relation to gradient and jet velocity.3 The presence of hypertrophy as a result of aortic stenosis or hypertension or both surely adds to the angina and heart failure and changes the course and outcome of the disease process. Another important thing to consider that a valve area of <1cm2 is a broad term; more critical stenosis and hypertrophy decrease the systemic arterial compliance leading to poor prognosis.

This has lead to authors to study the intrinsic myocardial dysfunction by speckle tracing showing a decreased longitudinal strain in presence of normal LVEF proving that the LVEF is not truly normal in these cases. Valve calcification on transesophageal echocardiography (TEE) and brain natriuretic peptide (BNP) levels may be helpful in decision making. So, with this ongoing unsettled debate, one expects to see changes and further refinement of the current guidelines in near future.

References

1. Hachicha Z, Dumesenil JG, Bogaty P, Paradoxycal low- flow, low-gradient severe aortic stenosis despite preserved ejection fraction is associated with higher afterload and reduced survival. Circulation 2007;115:2856-2864.

2. Barasch E, Fan D, Chukwu EO, Han J, Passick M, Petillo F, Norales A, Reichek N. Severe isolated aortic stenosis with normal left systolic function and low transvalvular gradient:pathophysiologic and prognostic insights. J Heart Valv Dis 2008;17:81-88.

3. Minners J, Allgeier M, Gohlke-Baerwolf C, Kienzle RP, Neumann FJ, Jander N. Inconsistent grading of aortic valve stenosis by current guidelines:hemodynamic studies in patients with apparently normal left ventricular function. Heart 2010;96:1463-1468.