Evaluation of left ventricular outflow tract gradient during treadmill exercise and in recovery period in orthostatic position, in patients with hypertrophic cardiomyopathy.
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.
Miranda
Rita
R
Hospital Garcia de Orta, Cardiology Department, Almada, Portugal. ritasmiranda@gmail.com
Cotrim
Carlos
C
Cardim
Nuno
N
Almeida
Sofia
S
Lopes
Luís
L
Loureiro
Maria José
MJ
Simões
Otília
O
Cordeiro
Pedro
P
Fazendas
Paula
P
João
Isabel
I
Carrageta
Manuel
M
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*