[Dobutamine stress echocardiography in patients with hypertrophic cardiomyopathy].
OBJECTIVE
To evaluate the safety and efficiency of the dobutamine stress echocardiography in patients with hypertrophic cardiomyopathy and estimate the difference between provokable obstruction and resting obstruction in these patients.


METHODS
Echocardiography was performed in 22 patients with HCM (LVOTPG < 50 mm Hg at rest, 1 mm Hg = 0.133 kPa) at rest and at the end point of dobutamine stress. Dobutamine was administered via an infusion pump, starting at a dose of 5 microg x min(-1) x kg(-1) and increasing every 5 minutes by 5 microg x min(-1) x kg(-1) till the maximum dose of 20 microg x min(-1) x kg(-1). Fifty-seven patients with HCM (LVOTPG > 50 mm Hg at rest) were also studied at rest.


RESULTS
In these 22 patients, the mean maximum velocity of LVOT was 5.39 +/- 1.60 m/s, the mean maximum LVOTPG was 125.7 +/- 62.4 mm Hg at the end point of dobutamine stress and the mean dose of dobutamine was 13.90 +/- 6.85 microg x min(-1)xkg(-1). Sixteen patients evidenced positive stress results at the end point of dobutamine stress. The main difference between the provokable obstruction and resting obstruction was that in provokable obstruction patients, the SAM positive patients were fewer and the proportion of Maron II patients was higher (50%).


CONCLUSIONS
Dobutamine stress echocardiography was a safe and sensitive way for detecting patients with hypertrophic cardiomyopathy. Provokable obstruction patients had fewer SAM and higher proportion of Maron II.
Yuan
Jian-song
JS
Coronary Heart Disease Center, Cardiovascular Institute and Fu Wai Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China.
Qiao
Shu-bin
SB
You
Shi-jie
SJ
Yang
Wei-xian
WX
Lü
Xiu-zhang
XZ
Hu
Feng-huan
FH
Gao
Run-lin
RL
Chen
Ji-lin
JL
Yang
Yue-jin
YJ
D000328:Adult; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D004280:Dobutamine / Q000008:administration & dosage; D025401:Echocardiography, Stress / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
D004280:Dobutamine