Affiliations 

  • 1 Department of Cardiology, National University Heart Centre, Singapore, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
  • 2 Department of Cardiology, National Heart Centre, Singapore, Singapore
  • 3 Department of Cardiology, Sarawak Heart Centre, Sarawak, Malaysia
  • 4 Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
  • 5 Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; Cardiovascular Research Institute, National University Health System, Singapore, Singapore
  • 6 Department of Cardiology, National University Heart Centre, Singapore, Singapore; Asian Heart and Vascular Centre, Mount Elizabeth Novena Hospital, Singapore, Singapore
  • 7 Department of Cardiology, National University Heart Centre, Singapore, Singapore
  • 8 Department of Cardiology, Tan Tock Seng Hospital, Singapore, Singapore
  • 9 Department of Cardiology, Tan Tock Seng Hospital, Singapore, Singapore; Apex Heart Clinic, Gleneagles Hospital, Singapore, Singapore
  • 10 Department of Cardiology, Changi General Hospital, Singapore, Singapore
  • 11 Asian Heart and Vascular Centre, Mount Elizabeth Novena Hospital, Singapore, Singapore
  • 12 Department of Cardiology, Khoo Teck Puat Hospital, Singapore, Singapore
  • 13 Department of Cardiology, National University Heart Centre, Singapore, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; Cardiovascular Research Institute, National University Health System, Singapore, Singapore; Christchurch Heart Institute, University of Otago, Dunedin, New Zealand
  • 14 Department of Cardiology, National University Heart Centre, Singapore, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; Cardiovascular Research Institute, National University Health System, Singapore, Singapore. Electronic address: mdcllh@nus.edu.sg
J Am Soc Echocardiogr, 2023 Jan;36(1):29-37.e5.
PMID: 36441088 DOI: 10.1016/j.echo.2022.10.011

Abstract

BACKGROUND: The role of left atrial (LA) strain as an imaging biomarker in aortic stenosis is not well established. The aim of this study was to investigate the prognostic performance of phasic LA strain in relation to clinical and echocardiographic variables and N-terminal pro-B-type natriuretic peptide in asymptomatic and minimally symptomatic patients with moderate to severe aortic stenosis and left ventricular ejection fraction > 50%.

METHODS: LA reservoir strain (LASr), LA conduit strain (LAScd), and LA contractile strain (LASct) were measured using speckle-tracking echocardiography. The primary outcome was a composite of all-cause mortality, heart failure hospitalization, progression to New York Heart Association functional class III or IV, acute coronary syndrome, or syncope. Secondary outcomes 1 and 2 comprised the same end points but excluded acute coronary syndrome and additionally syncope, respectively. The prognostic performance of phasic LA strain cutoffs was evaluated in competing risk analyses, aortic valve replacement being the competing risk.

RESULTS: Among 173 patients (mean age, 69 ± 11 years; mean peak transaortic velocity, 4.0 ± 0.8 m/sec), median LASr, LAScd, and LASct were 27% (interquartile range [IQR], 22%-32%), 12% (IQR, 8%-15%), and 16% (IQR, 13%-18%), respectively. Over a median of 2.7 years (IQR, 1.4-4.6 years), the primary outcome and secondary outcomes 1 and 2 occurred in 66 (38%), 62 (36%), and 59 (34%) patients, respectively. LASr < 20%, LAScd < 6%, and LASct < 12% were identified as optimal cutoffs of the primary outcome. In competing risk analyses, progressing from echocardiographic to echocardiographic-clinical and combined models incorporating N-terminal pro-B-type natriuretic peptide, LA strain parameters outperformed other key echocardiographic variables and significantly predicted clinical outcomes. LASr < 20% was associated with the primary outcome and secondary outcome 1, LAScd < 6% with all clinical outcomes, and LASct < 12% with secondary outcome 2. LAScd < 6% had the highest specificity (95%) and positive predictive value (82%) for the primary outcome, and competing risk models incorporating LAScd < 6% had the best discriminative value.

CONCLUSIONS: In well-compensated patients with moderate to severe aortic stenosis and preserved left ventricular ejection fractions, LA strain was superior to other echocardiographic indices and incremental to N-terminal pro-B-type natriuretic peptide for risk stratification. LAScd < 6%, LASr < 20%, and LASct < 12% identified patients at higher risk for adverse outcomes.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.