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Perfusion-contraction mismatch during inotropic stimulation in hibernating myocardium.
- Source :
-
Journal of nuclear medicine : official publication, Society of Nuclear Medicine [J Nucl Med] 1998 Mar; Vol. 39 (3), pp. 396-402. - Publication Year :
- 1998
-
Abstract
- Unlabelled: The aims of this study were to assess the value of dobutamine echocardiography in identifying myocardial hibernation versus stunning and to elucidate the underlying pathophysiological mechanism of the contractile impairment.<br />Methods: Twenty-one patients with isolated stenosis of the left anterior descending artery were evaluated 1 mo after thrombolysed acute anterior infarction. Regional function and blood flow were measured using echocardiography and PET at rest and during dobutamine administration (10 microg/kg/min).<br />Results: Defined by [18F]fluorodeoxyglucose uptake, 36 of 102 dyssynergic segments were necrotic, and 66 were viable. The latter segments were subdivided according to their [13N]ammonia flow distribution: 30 hibernating regions with perfusion defects (flow of <80% of maximum) and 36 stunned areas with preserved resting perfusion (flow of > or =80% of maximum). Resting flows were similar in necrosis and hibernation (0.43 +/- 0.18 versus 0.47 +/- 0.16 ml x min(-1) x g(-1); not significant), and both resting values were lower than those seen in stunning (0.79 +/- 0.24; p < 0.05). Flow response to dobutamine was markedly reduced in necrosis (dobutamine/resting flow = 1.16 +/- 0.27), whereas it was maintained in hibernation (1.65 +/- 0.54) and stunning (1.42 +/- 0.57). Dobutamine improved function in a higher number of stunned (55%) than hibernating (16%) or necrotic (11%) segments.<br />Conclusion: Dobutamine improves function mainly in stunned myocardium and does not reliably identify hibernation. The lack of functional response in hibernation is not related to an exhausted vasodilating capacity.
- Subjects :
- Coronary Angiography
Coronary Circulation drug effects
Female
Fluorine Radioisotopes
Fluorodeoxyglucose F18
Humans
Male
Middle Aged
Myocardial Stunning diagnostic imaging
Radiopharmaceuticals
Tomography, Emission-Computed
Cardiotonic Agents pharmacology
Dobutamine pharmacology
Echocardiography methods
Myocardial Contraction drug effects
Myocardial Stunning physiopathology
Subjects
Details
- Language :
- English
- ISSN :
- 0161-5505
- Volume :
- 39
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- Journal of nuclear medicine : official publication, Society of Nuclear Medicine
- Publication Type :
- Academic Journal
- Accession number :
- 9529281