title: Reduced left atrial function on exercise in patients with heart failure and normal ejection fraction.
abstract: OBJECTIVE
  The cardinal symptom of heart failure with a normal ejection fraction (HFNEF) is exertional dyspnoea. The authors hypothesised that failure of left atrial (LA) compensatory mechanism particularly on exercise contributes to the genesis of symptoms in HFNEF patients.
  
  
  RESULTS
  Fifty HFNEF patients, 15 asymptomatic hypertensive subjects and 30 healthy controls underwent rest and submaximal exercise echocardiography. Rest and exercise systolic, early diastolic and late diastolic (Am) mitral annular velocities were assessed using colour tissue Doppler echocardiography. Left atrial functional reserve index was calculated. Am at rest was comparable between all three groups, but exercise Am was significantly lower in HFNEF compared with hypertensive subjects and healthy controls resulting in a lower LA functional reserve index (0.84 (1.34) vs 2.39 (1.27) and 1.81 (1.39), p<0.001). LA volume index was significantly higher in HFNEF patients (30.4 (9.2) vs 27.9 (6.3) and 23.2 (7.1) ml/m(2), p=0.002). There was a significant correlation between Am on exercise with peak VO(2) max (r=0.514, p<0.001) and E/Em on exercise (r=-0.547, p<0.001). Area under the receiver operating characteristic for Am on exercise was 0.768 (95% CI=0.660 to 0.877).
  
  
  CONCLUSIONS
  HFNEF patients have reduced LA function on exercise in addition to left ventricular systolic and diastolic dysfunctions. Reduced LA function probably contributes significantly to exercise intolerance and breathlessness in HFNEF patients.
authors.affiliation: Department of Cardiovascular Medicine, University of Birmingham, Birmingham, UK.
authors.forename: Y T
authors.initials: YT
authors.lastname: Tan
authors.forename: F
authors.initials: F
authors.lastname: Wenzelburger
authors.forename: E
authors.initials: E
authors.lastname: Lee
authors.forename: P
authors.initials: P
authors.lastname: Nightingale
authors.forename: G
authors.initials: G
authors.lastname: Heatlie
authors.forename: F
authors.initials: F
authors.lastname: Leyva
authors.forename: J E
authors.initials: JE
authors.lastname: Sanderson
mesh_terms: D000368:Aged; D016279:Atrial Function, Left / Q000502:physiology*; D016022:Case-Control Studies; D004417:Dyspnea / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D054144:Heart Failure, Diastolic / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D012129:Respiratory Function Tests; D013318:Stroke Volume / Q000502:physiology*; D014463:Ultrasonography