RT Journal Article
SR Electronic
T1 <sup>201</sup>Tl SPECT Abnormalities, Documented at Rest in Dilated Cardiomyopathy, Are Related to a Lower Than Normal Myocardial Thickness but Not to an Excess in Myocardial Wall Stress
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 451
OP 457
VO 43
IS 4
A1 Hassan, Nathalie
A1 Escanyé, Jean-Marie
A1 Juillière, Yves
A1 Marie, Pierre-Yves
A1 David, Nicolas
A1 Olivier, Pierre
A1 Ayalew, Adey
A1 Karcher, Gilles
A1 Stolz, Jean-François
A1 Bertrand, Alain
YR 2002
UL http://jnm.snmjournals.org/content/43/4/451.abstract
AB This study was aimed at determining whether the 201Tl SPECT abnormalities documented in patients with dilated cardiomyopathy are related to a local excess in wall stress, which might act against the diastolic perfusion of myocardium. Methods: We included 6 healthy volunteers and 7 patients with idiopathic dilated cardiomyopathy who underwent 201Tl SPECT at rest. On a 13-segment division of the left ventricle, indices of wall stress and tension were calculated at end-diastole by applying Laplace’s law, with thickness and curvature radii being determined for each segment on 2 orthogonal MRI slices. Results: Among all patients, 21 analyzed segments had 201Tl SPECT defects (D+) and 67 had none (D−). Myocardial thickness was lower in D+ (0.88 ± 0.30 cm) than in D− (1.23 ± 0.33 cm, P = 0.0002) or in segments from healthy volunteers (0.99 ± 0.15 cm, P = 0.04). The index of end-diastolic wall tension was also lower in D+ (2.5 ± 1.0 N · m−1 · mm Hg−1) than in D− (3.3 ± 1.1 N · m−1 · mm Hg−1, P = 0.02) or in segments from healthy volunteers (3.2 ± 1.2 N · m−1 · mm Hg−1, P = 0.04). Last, the index of end-diastolic wall stress, determined by the ratio of wall tension index to myocardial thickness, was equivalent in D+, in D−, and in segments from healthy volunteers (respectively, 3.0 ± 1.4, 2.8 ± 1.2, and 3.2 ± 1.6 hN · m−2 · mm Hg−1). Conclusion: In patients with dilated cardiomyopathy, the abnormalities documented by 201Tl SPECT at rest are related to a lower than normal wall thickness and not to an excess in wall stress or tension. Therefore, partial-volume effects are likely to induce these abnormalities, and they may be unrelated to any insufficiency of myocardial perfusion.