valvular, arterial and ventricular interplay severe aortic stenosis: the importance of the Risk stratification in asymptomatic moderate to

Objective We sought to evaluate prognostic markers of clinical outcome in asymptomatic patients with moderate to severe aortic stenosis (AS). Design Prospective follow-up of asymptomatic patients with moderate to severe AS. The patients underwent clinical and Doppler echocardiographic evaluation. Setting Department of Cardiology. Patients 163 patients with moderate to severe AS (aortic valve area #0.6 cm/m). Main outcome measures Risk stratification. Predefined endpoints for assessing the outcome were the occurrence during follow-up of symptoms, aortic valve replacement or death. Results During follow-up (mean, 20 (19) months), 11 patients developed symptoms but were not operated on, 57 required aortic valve replacement and six patients died. In multivariable Cox regression analysis, four parameters that were associated with the outcome were identified: peak aortic jet velocity, left ventricular systolic (LV) longitudinal deformation, valvulo-arterial impedance and indexed left atrial area. Using receiver! operator characteristic curve analysis, a peak aortic jet velocity $4.4 m/s, a LV longitudinal myocardial deformation #15.9%, a valvular-arterial impedance $4.9 mm Hg/ml per m and an indexed left atrial area $12.2 cm/m were identified as the best cut-off values to be associated with events. Conclusions In asymptomatic patients with moderate to severe AS, measurements that integrate the ventricular, vascular and valvular components of the disease improve risk stratification. Aortic stenosis (AS) is the most common valvular disease in developed countries. Its prevalence is expected to markedly increase as the population ages. Patients with symptoms with severe AS have a high mortality rate and require prompt aortic valve replacement (AVR). Although asymptomatic patients are at increased risk for untoward events, their management remains controversial. 3 Current guidelines consider surgery as reasonable in asymptomatic patients with reduced (<50%) left ventricular (LV) ejection fraction and in patients who exhibit symptoms during an exercise test. 5 Improving the identification of patients at high risk of cardiac events is a challenging issue. We hypothetised that measurements integrating valvular, vascular and ventricular components of the disease could identify new markers of guarded prognosis and allow a better timing of intervention. To test this hypothesis, we prospectively studied consecutive patients with asymptomatic moderate to severe AS who did not fulfil current criteria of reasonable surgical option at the time of inclusion. METHODS Patient population A total of 163 asymptomatic patients with significant AS were enrolled between January 2000 and December 2007 in this prospective study. All patients met the following specific criteria: moderate to severe AS defined by an aortic valve area #0.6 cm/m, absence of symptoms according to a careful history taking by both the referring physician and us, normal LV ejection fraction ($55%) as calculated by two-dimensional echocardiography, no more than mild associated cardiac valve lesion and sinus rhythm. At study entry, the following clinical data were collected: age, gender, history of hypercholesterolemia (total cholesterol >190 mg/dl or patients under lipid lowering therapy), current smoking, diabetes mellitus, systemic arterial hypertension (blood pressure $ 140/90 mm Hg or patients under anti-hypertensive treatment) and overweight (body mass index >25 kg/m). The protocol was approved by the relevant institutional review boards and all patients gave written informed consent. Echocardiographic measurements Doppler echocardiographic examinations were performed with the use of a VIVID 7 ultrasound system (General Electric Healthcare, Little Chalfont, UK). M-mode, two-dimensional, colour Doppler and pulsed-wave and continuous-wave Doppler data were stored on a dedicated workstation for off-line analysis. For each measurement, at least two cardiac cycles were averaged. Continuous wave Doppler was used to measure the aortic transvalvular maximal velocities; peak and mean gradients were calculated using the simplified Bernoulli equation. Aortic valve area was calculated using the continuity equation. Stroke volume was calculated using the Doppler method as follows: 0.785 3 (LV outflow tract diameter) 3 LV outflow tract velocity time integral. LV end-diastolic and end-systolic volumes and ejection fraction were measured by the bi-apical Simpson disk method. Left atrial area was obtained by planimetry of an end-systolic frame from the apical four-chamber view. Peak E-wave and A-wave velocities of the mitral inflow were measured using pulsed wave Doppler. To complete the analysis of the LV systolic function, the global longitudinal myocardial Department of Cardiology, University Hospital Sart Tilman, Liège, Belgium CHU de Ponchaillou, Rennes, France Correspondence to P Lancellotti, Department of Cardiology, University Hospital, Domaine Universitaire du Sart Tilman B.35 4000 Liège, Belgium; plancellotti@chu.ulg. ac.be Accepted 24 February 2010 Lancellotti P, Donal E, Magne J, et al. Heart (2010). doi:10.1136/hrt.2009. 190942 1 of 8 Original article Heart Online First, published on May 18, 2010 as 10.1136/hrt.2009. 190942 Copyright Article author (or their employer) 2010. 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