title: Continuous wave Doppler measurements of aortic bloodflow during exercise in patients with chronic heart failure.
abstract: OBJECTIVE
  To assess the feasibility of obtaining continuous wave Doppler measurements of aortic bloodflow from the suprasternal notch during upright treadmill exercise as an objective adjunct to cardiac performance and functional capacity in heart failure.
  
  
  METHODS
  Prospective descriptive study.
  
  
  METHODS
  University teaching hospital out-patient heart failure clinic.
  
  
  METHODS
  Fifty-three patients with New York Heart Association (NYHA) class II or III heart failure (left ventricular ejection fraction 9 to 37%) and 15 control subjects of similar age but without heart disease.
  
  
  METHODS
  Symptom-limited (or to completion of 22-min protocol) treadmill exercise using a modified Naughton protocol.
  
  
  RESULTS
  Exercise duration was 11.3 +/- 0.6 mins for heart failure and 20.5 +/- 0.6 mins for normals. Both within subject and interobserver variability for the Doppler derived variables were satisfactory. There were no significant differences at rest between groups for any of the measured Doppler variables. In heart failure patients compared with normals, significant reductions in stroke distance and peak velocity occurred during stage I and in peak acceleration during stage II and persisted throughout exercise with reductions in maximum achieved peak velocity (0.64 +/- 0.02 versus 0.97 +/- 0.05 m/s, P < 0.001), peak acceleration (19.0 +/- 0.9 versus 37.3 +/- 2.4 m/s2, P < 0.001) and stroke distance (7.5 +/- 0.3 versus 11.2 +/- 0.6 cm, P < 0.001). Receiver operator curves had very favourable discriminating characteristics. No significant differences in Doppler indices were observed between patients due to etiology of heart failure or NYHA functional class.
  
  
  CONCLUSIONS
  Aortic bloodflow indices can be reliably measured from the suprasternal notch during upright treadmill exercise in the majority of heart failure patients. Since the indices were abnormal even at very early stages of exercise, further studies are required to define their usefulness as an adjunct in the assessment of heart failure patients whose maximum exercise tolerance is limited by other factors such as arthritis, intermittent claudication or lung disease.
authors.affiliation: Department of Medicine, Victoria Hospital, London, Ontario.
authors.forename: J M
authors.initials: JM
authors.lastname: Arnold
authors.forename: P
authors.initials: P
authors.lastname: Cheung
authors.forename: G L
authors.initials: GL
authors.lastname: Burton
mesh_terms: D000328:Adult; D000368:Aged; D001011:Aorta / Q000503:physiopathology*; D002311:Cardiomyopathy, Dilated / Q000150:complications; D002908:Chronic Disease; D003327:Coronary Disease / Q000150:complications; D015150:Echocardiography, Doppler / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006333:Heart Failure / Q000145:classification / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D015588:Observer Variation; D011446:Prospective Studies; D012039:Regional Blood Flow; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013318:Stroke Volume