Noninvasive vessel-selective perfusion imaging with intravenous myocardial contrast echocardiography.
BACKGROUND
Intravenous myocardial contrast echocardiography (MCE) cannot identify each perfusion area of coronary vessels separately. However, by destroying microbubbles passing through a specific vessel using high-power ultrasound during intravenous MCE, vessel-selective perfusion imaging (VSPI) may be feasible.


METHODS
In 10 open-chest dogs, intermittent short-axis images were obtained during contrast agent infusion using an ultrasound system. For VSPI, a probe coupled to another ultrasound machine was placed on the proximal left circumflex coronary artery (LCx). High-power ultrasound pulses were transmitted to destroy bubbles passing through the LCx. A negative contrast area on VSPI was considered to represent the perfusion area of the LCx (LCx-VSPI). A negative contrast area on conventional MCE during LCx occlusion and a region without staining by Evans blue dye were used as gold standards for defining the LCx perfusion area. LCx-VSPI was compared with a negative contrast area on conventional MCE during LCx occlusion and a region without staining by Evans blue dye.


RESULTS
Despite lack of LCx occlusion, high-power destructive pulses produced a definite area of negative contrast on the LCx region. Decreased power of ultrasound pulses resulted in disappearance of the negative contrast area. An excellent relationship was demonstrated between both LCx-VSPI and a negative contrast area on conventional MCE during LCx occlusion (r = 0.93, P <.0001), and LCx-VSPI and a region without staining by Evans blue dye (r = 0.92, P =.0002).


CONCLUSIONS
VSPI during intravenous MCE may be feasible for noninvasive assessment of perfusion areas associated with specific vessels.
Asanuma
Toshihiko
T
Department of Medical Physics, School of Allied Health Sciences, Faculty of Medicine, Osaka University, Suita, Japan.
Fujihara
Tomoko
T
Otani
Kentaro
K
Miki
Ayako
A
Ishikura
Fuminobu
F
Beppu
Shintaro
S
D000818:Animals; D003097:Collateral Circulation / Q000502:physiology; D004396:Coloring Agents; D003287:Contrast Media / Q000008:administration & dosage; D003326:Coronary Circulation / Q000502:physiology; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000473:pathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology; D004285:Dogs; D004452:Echocardiography / Q000295:instrumentation / Q000379:methods*; D005070:Evans Blue; D005240:Feasibility Studies; D005466:Fluorocarbons; D007275:Injections, Intravenous; D045423:Microbubbles; D008863:Microspheres; D010210:Papillary Muscles / Q000000981:diagnostic imaging / Q000473:pathology; D014159:Transducers
D004396:Coloring Agents; D003287:Contrast Media; D005466:Fluorocarbons; D005070:Evans Blue; C042852:perflutren