title: Circumferential vascular strain rate to estimate vascular load in aortic stenosis: a speckle tracking echocardiography study.
abstract: Evaluation of vascular mechanics through two-dimensional speckle-tracking (2D-ST) echocardiography is a feasible and accurate approach for assessing vascular stiffening. Degenerative aortic stenosis (AS) is currently considered a systemic vascular disease where rigidity of arterial walls increases. To assess the circumferential ascending aorta strain rate (CAASR) in thoracic aortas of patients with AS, applying 2D-ST technology. 45 patients with indexed aortic valve areas (iAVA) ≤0.85 cm(2)/m(2) were studied. Global CAASR served to assess vascular deformation. Clinical, echocardiographic, and non-invasive hemodynamic data were collected. A follow up (955 days) was also performed. Average age of the cohort was 76. ± 10.3 years, with gender balance. Mean iAVA was 0.43 ± 0.15 cm(2)/m(2). Waveforms adequate for determining CAASR were found in 246 (91 %) of the 270 aortic segments evaluated, for a mean global CAASR of 0.74 ± 0.26 s(-1). Both intra- and inter-observer variability of global CAASR were deemed appropriate. CAASR correlated significantly with age (r = -0.49, p < 0.01), the stiffness index (r = -0.59, p < 0.01), systemic arterial compliance and total vascular resistance. There was a significant positive correlation between CAASR, body surface area (BSA), iAVA, and a negative relationship with valvulo-arterial impedance and E/e' ratio (r = -0.37, p = 0.01). The stiffness index was (β = -0.41, p < 0.01) independently associated with CAASR, in a model adjusted for age, BSA, iAVA and E/e'. Patients with a baseline CAASR ≤0.66 s(-1) had a worse long-term outcome (survival 52.4 vs. 83.3 %, Log Rank p = 0.04). CAASR is a promising echocardiographic tool for studying the vascular loading component of patients with AS.
authors.affiliation: Departamento de Medicina, Serviço de Cardiologia, Hospital Beatriz Ângelo, Avenida Carlos Teixeira - 3, 2674-514, Loures, Portugal, rogeriopteixeira@gmail.com.
authors.forename: Rogério
authors.initials: R
authors.lastname: Teixeira
authors.forename: Ricardo
authors.initials: R
authors.lastname: Monteiro
authors.forename: Rui
authors.initials: R
authors.lastname: Baptista
authors.forename: António
authors.initials: A
authors.lastname: Barbosa
authors.forename: Luís
authors.initials: L
authors.lastname: Leite
authors.forename: Miguel
authors.initials: M
authors.lastname: Ribeiro
authors.forename: Rui
authors.initials: R
authors.lastname: Martins
authors.forename: Nuno
authors.initials: N
authors.lastname: Cardim
authors.forename: Lino
authors.initials: L
authors.lastname: Gonçalves
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging* / Q000503:physiopathology; D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000401:mortality / Q000503:physiopathology; D062186:Arterial Pressure; D015150:Echocardiography, Doppler; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D015588:Observer Variation; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013314:Stress, Mechanical; D013997:Time Factors; D059289:Vascular Stiffness; D016277:Ventricular Function, Left