RT Journal Article
SR Electronic
T1 Comparison of Regional Myocardial Blood Flow and Perfusion in Dilated Cardiomyopathy and Left Bundle Branch Block: Role of Wall Thickening
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 414
OP 418
VO 45
IS 3
A1 Nowak, Bernd
A1 Stellbrink, Christoph
A1 Schaefer, Wolfgang M.
A1 Sinha, Anil M.
A1 Breithardt, Ole A.
A1 Kaiser, Hans-Juergen
A1 Reinartz, Patrick
A1 Hanrath, Peter
A1 Buell, Ulrich
YR 2004
UL http://jnm.snmjournals.org/content/45/3/414.abstract
AB Heterogeneous perfusion in left bundle branch block (LBBB) has been demonstrated by 99mTc-methoxyisobutylisonitrile (MIBI) SPECT. Locally different contraction is also associated with LBBB. Quantitative analysis of myocardial SPECT is influenced by partial-volume effects depending on systolic wall thickening. Therefore, partial-volume effects may mimic perfusion heterogeneity in LBBB. Methods: Fifteen patients with nonischemic dilated cardiomyopathy and LBBB underwent resting 15O-water PET, 99mTc-MIBI SPECT, and gated 18F-FDG PET for analysis of wall thickening. Myocardial blood flow corrected for rate–pressure product (corrMBF), 99mTc-MIBI uptake, and wall thickening were determined in 4 left ventricular wall areas. In 14 patients, M-mode echocardiographic recordings were available for comparison. Results: Homogeneous distribution was found for corrMBF (1.09 ± 0.41 to 1.19 ± 0.31 mL × g−1 × min−1). 99mTc-MIBI uptake and wall thickening were heterogeneous (P < 0.0001), with the lowest values septal (99mTc-MIBI, 65% ± 10%; wall thickening, 16% ± 14%) and the highest lateral (99mTc-MIBI, 84% ± 5%; wall thickening, 55% ± 17%). Similar relationships in systolic wall thickening were observed by M-mode echocardiography (anteroseptal, 20% ± 11%; posterolateral, 37% ± 18%; P < 0.001). Conclusion: Heterogeneity of 99mTc-MIBI uptake in LBBB corresponds to differences in wall thickening and does not reflect distribution of corrMBF. Supplementary analysis of wall thickening is recommended when assessing 99mTc-MIBI SPECT in LBBB.