Comparison of endocardial electromechanical mapping with radionuclide perfusion imaging to assess myocardial viability and severity of myocardial ischemia in angina pectoris.
The assessment of left ventricular electromechanical activity using a novel, nonfluoroscopic 3-dimensional mapping system demonstrates considerable differences in electrical and mechanical activities within regions of myocardial infarction or ischemia. We sought to determine whether these changes correlate with indexes of myocardial perfusion, viability, or ischemia. A 12-segment comparative analysis was performed in 61 patients (45 men, 61 +/- 12 years old) with class III to IV angina, having reversible and/or fixed myocardial perfusion defects on single-photon emission computed tomographic perfusion imaging. A dual-isotope protocol was used, consisting of rest and 4-hour redistribution thallium images followed by adenosine technetium-99m sestamibi imaging. Average rest endocardial unipolar voltage (UpV) and local shortening (LS) mapping values were compared with visually derived perfusion scores. There was gradual and proportional reduction in regional UpV and LS in relation to thallium-201 uptake score at rest (p = 0.0001 and p = 0.0002, respectively) and redistribution studies (p = 0.0001 and p = 0.003, respectively). UpV > or = 7.4 mV and LS > or = 5.0% had a sensitivity of 78% and 65%, respectively, with a specificity of 68% and 67% for detecting viable myocardium. UpV values of 12.3 and 5.4 mV had 90% specificity and sensitivity, respectively, to predict viable tissue. UpV, but not LS, values differentiated between normal segments and those with adenosine-induced severe perfusion defects (11.8 +/- 5.3 vs 8.8 +/- 4.1 mV, p = 0.005). Catheter-based left ventricular assessment of electromechanical activity correlates with the degree of single-photon emission computed tomographic perfusion abnormality and can identify myocardial viability with a greater accuracy than myocardial ischemia.
Fuchs
S
S
Myocardial Revascularization Program, The Cardiovascular Research Foundation, Washington Hospital Center, Washington, DC 20010, USA. sxf6@mhg.edu
Hendel
R C
RC
Baim
D S
DS
Moses
J W
JW
Pierre
A
A
Laham
R J
RJ
Hong
M K
MK
Kuntz
R E
RE
Pietrusewicz
M
M
Bonow
R O
RO
Mintz
G S
GS
Leon
M B
MB
Kornowski
R
R
D000241:Adenosine; D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000000981:diagnostic imaging / Q000503:physiopathology; D015331:Cohort Studies; D004594:Electrophysiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D011237:Predictive Value of Tests; D011859:Radiography; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon; D014481:United States; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging
D013794:Thallium Radioisotopes; D017256:Technetium Tc 99m Sestamibi; D000241:Adenosine