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Clin. Cardiol. 23, 409-414 (2000)

Low-Dose Dobutamine Radionuclide Ventriculography for Prediction of Myocardial Viability: Quantitative Analysis of Regional Left Ventricular Function

Noriyuki Takeyasu, M.D., Shigeyuki Watanabe, M.D., Ryuichi Ajisaka, M.D.,† Kazuhiko Eda, M.D., Masahiro Toyama, M.D., Kazuhiko Sakamoto, M.D., Takumi Saito, M.D., Takayoshi Yamanouchi, M.D., Takeshi Masuoka, M.D., Tohru Takeda, M.D.,* Yuji Itai, M.D.,* Yasuro Sugishita, M.D., Ph.D., FACC,‡ Iwao Yamaguchi, M.D.

Cardiovascular Division, Departments of Internal Medicine and *Radiology, Institute of Clinical Medicine; †Institute of Health and Sport Sciences, University of Tsukuba; ‡Tsukuba Memorial Hospital, Tsukuba, Ibaraki, Japan

Summary

Background: It is important to distinguish viable myocardium from necrotic tissue in order to decide upon therapy in patients with ischemic heart disease.

Hypothesis: We verified the hypothesis that quantitative analysis of regional left ventricular function using low-dose dobutamine radionuclide ventriculography (RNV) can sensitively predict myocardial viability and compared its usefulness with thallium-201 (201Tl) single-photon emission computed tomography (201Tl-SPECT).

Methods: Radionuclide ventriculography at rest and during low-dose dobutamine infusion (5 µg/kg/min), 201Tl-SPECT, and coronary angiography were performed in 51 subjects with severe ischemia-related stenosis of coronary arteries and 3 subjects without coronary artery disease. 201Tl uptake was assessed as normal (control), low perfusion (LP), or defect. We compared the response of regional function to dobutamine with the regional 201Tl uptake. The accuracy of both methods for identifying viable myocardium was investigated in 17 patients who underwent successful coronary revascularization, with a resulting improvement in wall motion.

Results: The increase in regional ejection fraction (Δr-EF) in response to dobutamine was significantly greater in the control (12 ± 6%) and LP (16 ± 11%) regions than in the defect (5 ± 10%) regions. The increase in one-third regional ejection fraction (Δr-1/3EF) was also significantly higher in the control (14 ± 7%) and LP (10 ± 8%) regions than in the defect regions (5 ± 6%). We defined myocardial viability as a Δr-EF >5% or a Δr-1/3EF >2%. The sensitivity and specificity of the Δr-EF for identification of myocardial viability were 91.4 and 55.5%, respectively. The sensitivity and specificity of the Δr-1/3EF were 91.4 and 66.6%, respectively; the corresponding values for 201Tl SPECT were 74.2 and 77.8%.

Conclusion: Low-dose dobutamine RNV with quantitative analysis of regional left ventricular function was more sensitive for identification of viable myocardium than 201Tl-SPECT.

Key words: myocardial viability, dobutamine, radionuclide ventriculography, regional left ventricular function, thallium-201 myocardial scintigraphy

Address for reprints:
Shigeyuki Watanabe, M.D.
Department of Internal Medicine
Institute of Clinical Medicine
University of Tsukuba
1-1-1, Tennoudai, Tsukuba
Ibaraki,305-8575, Japan

Received: May 11, 1999
Accepted with revision: August 12, 1999

JUNE 2000:    Contents    Previous   Next