title: Evaluation of left ventricular outflow tract gradient during treadmill exercise and in recovery period in orthostatic position, in patients with hypertrophic cardiomyopathy.
abstract: BACKGROUND
  Left ventricular outflow tract obstruction is an independent predictor of adverse outcome in hypertrophic cardiomyopathy (HCM). The classical quantification of intraventricular obstruction is performed in resting conditions in supine position, but this assessment does not reflect what happens in HCM patients (pts) in their daily activities, neither during effort nor during orthostatic recovery.
  
  
  OBJECTIVE
  To assess intraventricular gradients with echocardiography during treadmill exercise and in the recovery period in upright position, in HCM pts.
  
  
  METHODS
  We studied 17 HCM pts (9 males, mean age 53 +/- 16 years, 11 with obstructive HCM). Each pt had 2 echocardiographic evaluations at rest (left lateral decubitus (LLD) and orthostatic position). The pts then underwent a treadmill exercise test and intraventricular gradients were measured at peak exercise and during recovery in orthostatic position.
  
  
  RESULTS
  3 pts with non-obstructive HCM at rest developed intraventricular gradients during exercise. 1 pt developed this gradient only during orthostatic recovery. The mean intraventricular gradient in LLD was 49 +/- 24 mmHg; in orthostatic position was 62 +/- 29 mmHg (p < 0.001 versus in LLD); at peak exercise was 83 +/- 35 mmHg (p < 0.001 versus supine rest); during recovery it was 96 +/- 35 mmHg (p < 0.001 versus peak exercise)
  
  
  CONCLUSIONS
  In HCM pts the intraventricular gradient increases in orthostatic position, increases significantly during treadmill exercise and continues increasing in the recovery period in orthostatic position. This type of evaluation can help us to better understand the physiopathology, the symptoms and the efficacy of different therapeutic modalities in this disease and should be routinely used in the assessment of HCM pts.
authors.affiliation: Hospital Garcia de Orta, Cardiology Department, Almada, Portugal. ritasmiranda@gmail.com
authors.forename: Rita
authors.initials: R
authors.lastname: Miranda
authors.forename: Carlos
authors.initials: C
authors.lastname: Cotrim
authors.forename: Nuno
authors.initials: N
authors.lastname: Cardim
authors.forename: Sofia
authors.initials: S
authors.lastname: Almeida
authors.forename: Luís
authors.initials: L
authors.lastname: Lopes
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Loureiro
authors.forename: Otília
authors.initials: O
authors.lastname: Simões
authors.forename: Pedro
authors.initials: P
authors.lastname: Cordeiro
authors.forename: Paula
authors.initials: P
authors.lastname: Fazendas
authors.forename: Isabel
authors.initials: I
authors.lastname: João
authors.forename: Manuel
authors.initials: M
authors.lastname: Carrageta
mesh_terms: D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000000981:diagnostic imaging*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D014694:Ventricular Outflow Obstruction / Q000150:complications* / Q000000981:diagnostic imaging*