MR flow mapping of dobutamine-induced changes in diastolic heart function.
OBJECTIVE
To evaluate the ability of MR flow mapping to measure changes in left ventricular filling during beta-adrenergic stimulation.


METHODS
Mitral flow was measured in 10 healthy volunteers using conventional free breathing fast-field echo (FFE) with a spatial resolution of 2.7 x 2.2 mm and a temporal resolution of 22 msec. The sequence was repeated during dobutamine infusion (20 microg/kg/minute).


RESULTS
Stroke volume increased from a median of 99 mL (range: 68-142 mL) (Note: values as presented are medians and ranges, throughout) to 114 mL (87-180 mL) (P < 0.05). Both early (E) peak filling rate (554 mL/second [433-497 mL] to 651 mL/second [496-1096 mL/second]) (P < 0.05) and atrial (A) peak filling rate (238 mL/second [183-352 mL/second] to 341 mL/second [230-538 mL/second]) (P < 0.05) increased. These changes, together with the increase in E acceleration peak and A deceleration peak, were consistent with facilitated myocardial relaxation.


CONCLUSIONS
Conventional free breathing FFE has the ability to measure the effects of beta-adrenergic stimulation on left ventricular filling.
Paelinck
Bernard P
BP
University Hospital Antwerp, Antwerp, Belgium. Bernard.paelinck@uza.be
Lamb
Hildo J
HJ
Bax
Jeroen J
JJ
van der Wall
Ernst E
EE
de Roos
Albert
A
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000328:Adult; D002302:Cardiac Output / Q000187:drug effects; D003326:Coronary Circulation / Q000502:physiology*; D003971:Diastole / Q000187:drug effects; D004280:Dobutamine / Q000494:pharmacology*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008943:Mitral Valve / Q000502:physiology; D012016:Reference Values; D015203:Reproducibility of Results; D013318:Stroke Volume / Q000187:drug effects; D013997:Time Factors; D016277:Ventricular Function, Left / Q000187:drug effects*
D000318:Adrenergic beta-Agonists; D004280:Dobutamine