Detection of myocardial perfusion abnormalities after a recent acute coronary syndrome by quantitative Levovist myocardial contrast echocardiography: comparison with 99m Tc-Myoview SPECT imaging.
BACKGROUND
The value of stress harmonic power Doppler imaging (HPDI) for the evaluation of myocardial perfusion has never been assessed in patients after acute coronary syndrome (ACS).


OBJECTIVE
To evaluate the agreement between stress HPDI and single photon emission computed tomography (SPECT) imaging for the assessment of myocardial perfusion after unstable angina or myocardial infarction.


METHODS
Thirty patients with a recent ACS underwent HPDI and SPECT. Images were obtained at rest and during dipyridamole infusion (0.56 mg/kg over 4 min). Apical two- and four-chamber views were used for HPDI. Ten myocardial segments were scored for myocardial perfusion. Semiquantitative and quantitative video intensity analysis with background subtraction were performed.


RESULTS
Concordance by patients between quantitative HPDI and SPECT was 76% (kappa=0.40, Phi=0.46) for normal versus abnormal perfusion. When semiquantitative analysis was used, concordance was 72% (kappa=0.42, Phi=0.46). Agreement between methods was best in the left anterior descending artery territory for quantitative (80%) (kappa=0.60, Phi=0.60) and semiquantitative analysis (78%) (kappa=0.51, Phi=0.60) for normal versus abnormal perfusion. Discrepancies between HPDI and SPECT were most important in the circumflex territory, with a concordance of 59% (kappa=0.22) for identification of normal perfusion versus irreversible and reversible defects.


CONCLUSIONS
These results suggest that HPDI can detect myocardial perfusion at rest and during pharmacological stress in patients after a recent ACS. Given the suboptimal agreement with SPECT, further advances are required before the routine use of contrast echocardiography is possible for the assessment of myocardial perfusion.
Fernandes
Luciana P
LP
Division of Medicine, Montréal Heart Institute, Montréal, Québec.
Tardif
Jean-Claude
JC
Arsenault
André
A
Grégoire
Jean
J
Basmadjian
Arsene
A
Couturier
André
A
Vannan
Mani
M
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D003326:Coronary Circulation; D003327:Coronary Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004452:Echocardiography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011134:Polysaccharides; D019275:Radiopharmaceuticals; D012107:Research Design; D013577:Syndrome; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
D003287:Contrast Media; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011134:Polysaccharides; D019275:Radiopharmaceuticals; C059891:SHU 508; C078700:technetium tc-99m tetrofosmin