Prognostic Value of Left Ventricular Deformation Parameters in Patients with Severe Aortic Stenosis: A Pilot Study of the Usefulness of Strain Echocardiography

• Published in: Journal of the American Society of Echocardiography Vol. 30; no. 8; pp. 727 - 735.e1
• Main Authors: Klaeboe, Lars Gunnar, MD, Haland, Trine F., MD, Leren, Ida S., MD, PhD, ter Bekke, Rachel M.A., MD, Brekke, Pål H., MD, PhD, Røsjø, Helge, MD, PhD, Omland, Torbjørn, MD, PhD, Gullestad, Lars, MD, PhD, Aakhus, Svend, MD, PhD, Haugaa, Kristina H., MD, PhD, Edvardsen, Thor, MD, PhD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-08-2017
• Subjects: Aged; Aortic stenosis; Aortic Valve - diagnostic imaging; Aortic Valve Stenosis - diagnosis; Aortic Valve Stenosis - epidemiology; Aortic Valve Stenosis - physiopathology; Cardiovascular; Cause of Death; Echocardiography, Stress - methods; Echocardiography, Stress - utilization; Feasibility Studies; Female; Heart Ventricles - diagnostic imaging; Heart Ventricles - physiopathology; Humans; Male; Morbidity - trends; Norway - epidemiology; Pilot Projects; Prospective Studies; Risk Assessment; Risk Factors; ROC Curve; Severity of Illness Index; Speckle-tracking echocardiography; Stroke Volume - physiology; Survival Rate - trends; Ventricular function; Ventricular Function, Left - physiology; Aortic stenosis; Zva; CAD; Left ventricular; LVEF; Global longitudinal strain; HR; LV; AVA; Coronary artery disease; Hazard ratio; GLS; Speckle-tracking echocardiography; AS; Valvulo-arterial impedance; AV; Risk assessment; Left ventricular ejection fraction; Ventricular function; Aortic valve replacement; Aortic valve; AVR; Aortic valve area
• ISSN: 0894-7317; 1097-6795
• DOI: 10.1016/j.echo.2017.04.009

Background In patients with aortic stenosis, subtle alterations in myocardial mechanics can be detected by speckle-tracking echocardiography before reduction of left ventricular ejection fraction (LVEF). Methods In this prospective study, 162 patients with aortic stenosis with an average aortic valve area of 0.7 ± 0.2 cm2 and a mean LVEF of 60 ± 11% were included. Global longitudinal strain (GLS) and mechanical dispersion (SD of time from Q/R on the electrocardiogram to peak strain in 16 left ventricular segments) were assessed using echocardiography, and all-cause mortality ( n  = 37) was recorded during 37 ± 13 months of follow-up. Results Overall, nonsurvivors had more pronounced mechanical dispersion and worse GLS compared with survivors (74 ± 24 vs 61 ± 18 msec [ P  < .01] and −14.5 ± 4.4% vs −16.7 ± 3.6% [ P  < .01], respectively). In the 42 conservatively treated patients without surgical aortic valve replacement, a similar pattern was observed in nonsurvivors versus survivors (mechanical dispersion, 80 ± 24 vs 57 ± 14 msec [ P  < .01]; GLS, −14.0 ± 4.9% vs −17.1 ± 3.8% [ P  = .04], respectively). Mechanical dispersion was significantly associated with mortality (hazard ratio per 10-msec increase, 1.23; 95% CI, 1.07–1.42; P  < .01) in a Cox model adjusted for LVEF and with aortic valve replacement treatment as a time-dependent covariate. Continuous net reclassification improvement showed that mechanical dispersion was incremental to LVEF, GLS, and valvulo-arterial impedance when adjusting for aortic valve replacement treatment in the total population. Conclusion Increased mechanical dispersion may be a risk marker providing novel prognostic information in patients with aortic stenosis.