Assessment of myocardial response to pharmacologic interventions using an improved MR imaging technique to estimate T2 values.

OBJECTIVE Our objective was to improve a previously developed MR imaging sequence for the in vivo estimation of the myocardial T2* value and to evaluate, in healthy human subjects, the response of myocardial T2* value to two different pharmacologic interventions. CONCLUSION The modified technique improved the quality of the images obtained and increased the reliability of myocardial T2* measurements. Using the modified technique, the myocardial T2* value increased significantly over baseline values after the administration of dipyridamole but did not significantly change after the administration of dobutamine. These observations are consistent with the expected response of myocardial venous blood oxygen saturation levels to the infusion of the two pharmacologic agents.

[1]  K. Uğurbil,et al.  Contrast‐enhanced first pass myocardial perfusion imaging: Correlation between myocardial blood flow in dogs at rest and during hyperemia , 1993, Magnetic resonance in medicine.

[2]  D Chien,et al.  Fast selective black blood MR imaging. , 1991, Radiology.

[3]  V. P. Chacko,et al.  Oxygenation in the rabbit myocardium: assessment with susceptibility-dependent MR imaging. , 1993, Radiology.

[4]  S. Reeder,et al.  Blood oxygenation dependence of t1 and t2 in the isolated, perfused rabbit heart at 4.7t , 1995, Magnetic resonance in medicine.

[5]  A. D. de Crespigny,et al.  Endogenous susceptibility contrast in myocardium during apnea measured using gradient recalled echo planar imaging , 1993, Magnetic resonance in medicine.

[6]  R. Gropler,et al.  Functional recovery after coronary revascularization for chronic coronary artery disease is dependent on maintenance of oxidative metabolism. , 1992, Journal of the American College of Cardiology.

[7]  E. Haacke,et al.  Myocardial signal response to dipyridamole and dobutamine: Demonstration of the BOLD effect using a double‐echo gradient‐echo sequence , 1996, Magnetic resonance in medicine.

[8]  R. Turner,et al.  Dynamic magnetic resonance imaging of human brain activity during primary sensory stimulation. , 1992, Proceedings of the National Academy of Sciences of the United States of America.

[9]  E. Haacke,et al.  Theory of NMR signal behavior in magnetically inhomogeneous tissues: The static dephasing regime , 1994, Magnetic resonance in medicine.

[10]  B. Rosen,et al.  Myocardial intensity changes associated with flow stimulation in blood oxygenation sensitive magnetic resonance imaging , 1996, Magnetic resonance in medicine.

[11]  J C Gore,et al.  Physiologic basis for BOLD MR signal changes due to hypoxia/hyperoxia: Separation of blood volume and magnetic susceptibility effects , 1997, Magnetic resonance in medicine.

[12]  R. Turner,et al.  Effect of cardiac flow on gradient recalled echo images of the canine heart , 1994, NMR in biomedicine.

[13]  B. Sobel,et al.  Dependence of recovery of contractile function on maintenance of oxidative metabolism after myocardial infarction. , 1992, Journal of the American College of Cardiology.