title: Right ventricular longitudinal strain for risk stratification in low-flow, low-gradient aortic stenosis with low ejection fraction.
abstract: BACKGROUND
  Left ventricular global longitudinal strain (LVLS) is a powerful predictor of outcome in patients with low-flow, low-gradient aortic stenosis (LF-LG AS) and low LV ejection fraction (LVEF). However, the impact of right ventricular (RV) function on the outcome of these patients remains unknown.
  
  
  OBJECTIVE
  The aim of this study was to examine the impact of RV function as evaluated by RV free wall longitudinal strain (RVLS) on mortality in patients with LF-LG AS and low LVEF.
  
  
  METHODS
  211 patients with LF-LG AS (mean gradient < 40 mm Hg and indexed aortic valve area (AVA) ≤ 0.6 cm²/m²) and low LVEF (≤ 40%)) were prospectively recruited in the True or Pseudo-severe Aortic Stenosis study. AS severity was assessed using the projected AVA (AVAproj) at normal flow rate. Among the 211 patients, 128 had RVLS measurement available at rest and were included in this analysis. RVLS measurement at dobutamine stress echocardiography (DSE) was available in 58 of the 128 patients.
  
  
  RESULTS
  Two-year survival was lower in patients with RVLS < |13|% (53% ± 9%) compared with those with RVLS > |13|% (69% ± 5%) (p = 0.04). In multivariable Cox analysis stratified for the type of treatment (aortic valve replacement vs conservative) and adjusted for age, AS severity, previous myocardial infarction and LVLS, rest RVLS < |13|% (HR = 2.70; 95% CI 1.19 to 6.11; p = 0.018) was independently associated with all-cause mortality. RVLS had incremental prognostic value over baseline risk factors and LVLS (χ² = 20.13 vs 13.56; p = 0.01). Reduced stress RVLS was also associated with increased risk of mortality (stress RVLS <| 14|%: HR = 2.98; 95% CI 1.30 to 6.52; p = 0.01). In multivariable Cox analysis, stress RVLS < |14|% remained independently associated with mortality (HR = 2.94; 95% CI 1.23 to 7.02; p = 0.015). After further adjustment for rest RVLS, stress RVLS < |14|% remained independently associated with mortality (HR = 3.29; 95% CI 1.17 to 9.25; p = 0.024), whereas rest RVLS was not (p > 0.05).
  
  
  CONCLUSIONS
  In this series of patients with LF-LG AS and low LVEF, reduced RVLS was independently associated with increased risk of mortality. Furthermore, stress RVLS provided incremental prognostic value beyond that obtained from rest RVLS. Thus, RVLS measurement at rest and at DSE may be helpful to enhance risk stratification in this high-risk population.
  
  
  BACKGROUND
  NCT01835028; Results.
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Abdellaziz
authors.initials: A
authors.lastname: Dahou
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Marie-Annick
authors.initials: MA
authors.lastname: Clavel
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Romain
authors.initials: R
authors.lastname: Capoulade
authors.affiliation: Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Vienna, Austria.
authors.forename: Philipp Emanuel
authors.initials: PE
authors.lastname: Bartko
authors.affiliation: Service Cardiologie, CHU Limoges, Hôpital Dupuytren, Limoges, France Faculté de médecine de Limoges, INSERM 1094, Limoges, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Magne
authors.affiliation: Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Vienna, Austria.
authors.forename: Gerald
authors.initials: G
authors.lastname: Mundigler
authors.affiliation: Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Vienna, Austria.
authors.forename: Jutta
authors.initials: J
authors.lastname: Bergler-Klein
authors.affiliation: University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
authors.forename: Ian
authors.initials: I
authors.lastname: Burwash
authors.affiliation: Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Vienna, Austria.
authors.forename: Julia
authors.initials: J
authors.lastname: Mascherbauer
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Henrique B
authors.initials: HB
authors.lastname: Ribeiro
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Kim
authors.initials: K
authors.lastname: O'Connor
authors.affiliation: Division of Adult Congenital and Valvular Heart Disease, Department of Cardiovascular Medicine, University Hospital Muenster, Muenster, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Baumgartner
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Mario
authors.initials: M
authors.lastname: Sénéchal
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Jean G
authors.initials: JG
authors.lastname: Dumesnil
authors.affiliation: Department of Internal Medicine II, Division of Cardiology, Medical University of Vienna, Vienna, Austria.
authors.forename: Raphael
authors.initials: R
authors.lastname: Rosenhek
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: Mathieu
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Larose
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Josep
authors.initials: J
authors.lastname: Rodés-Cabau
authors.affiliation: Institut Universitaire de Cardiologie et de Pneumologie de Québec/Québec Heart & Lung Institute, Laval University, Québec City, Québec, Canada.
authors.forename: Philippe
authors.initials: P
authors.lastname: Pibarot
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000503:physiopathology; D025401:Echocardiography, Stress / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013318:Stroke Volume; D016277:Ventricular Function, Left