title: Significance of systolic anterior motion of the mitral valve during dobutamine stress echocardiography.
abstract: Left ventricular outflow tract obstruction related to systolic anterior motion of the mitral valve (SAM) induced during dobutamine stress echocardiography (DSE) is not unusual but its significance is not established. A total of 100 consecutive patients (mean age 62 +/- 12 years; 67% male) without previous transmural myocardial infarction, valvular disease, or hypertrophic cardiomyopathy, undergoing DSE to assess the presence of myocardial ischemia, were prospectively evaluated. A SAM with DSE was searched and correlated with clinical and baseline echocardiographic findings. Patients who demonstrated SAM with DSE were selected for exercise echocardiographic Doppler study with bicycle, within 6 months of the DSE. The development of an intraventricular gradient with DSE or exercise was defined as a new gradient of > or =36 mm Hg. In all, 23 patients developed SAM during DSE with a mean gradient of 79 +/- 33 mm Hg (range: 39-144 mm Hg) and mitral regurgitation related to SAM. Compared with patients without SAM, patients who developed SAM with DSE were characterized at rest by a smaller mitroaortic angle and septoaortic angle, a higher posterior mitral leaflet length, and a smaller left ventricular cavity. Neither ischemic nor hypotensive response during DSE were correlated to SAM. In the group of patients with SAM, of the 9 patients who were referred for unexplained chest pain or dyspnea, 5 reproduced symptoms with DSE, compared with 2 of 17 patients in the group without SAM (P = .005). Despite these findings, only 3 of the 16 patients who underwent exercise echocardiography Doppler study developed SAM (two with symptoms), with a wide range of achieved heart rate, compared with DSE. Although patients with SAM with DSE exhibit predisposing echocardiographic findings, the clinical impact of this phenomenon is real in only a minority of patients, particularly those who experienced unexplained dyspnea or chest pain.
authors.affiliation: Department of Cardiology and Intensive Care Unit, Centre Hospitalier de Compiegne, 60200 Compiegne, France. pmeimoun001@ch-compiegne.rss.fr
authors.forename: Patrick
authors.initials: P
authors.lastname: Meimoun
authors.forename: Tahar
authors.initials: T
authors.lastname: Benali
authors.forename: Smain
authors.initials: S
authors.lastname: Sayah
authors.forename: Anne
authors.initials: A
authors.lastname: Luycx-Bore
authors.forename: Brigite
authors.initials: B
authors.lastname: Maitre
authors.forename: Christophe
authors.initials: C
authors.lastname: Tribouilloy
mesh_terms: D000368:Aged; D015150:Echocardiography, Doppler; D025401:Echocardiography, Stress; D005080:Exercise Test; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000503:physiopathology*; D014694:Ventricular Outflow Obstruction / Q000503:physiopathology*