ISSN:
1619-7089
Keywords:
Key words: Myocardial adrenergic innervation
;
Myocardial infarction
;
Metaiodobenzylguanidine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract. In spite of smaller infarct size and better preserved left ventricular function the long-term prognosis after a non-Q-wave infarction is not better than after a Q-wave infarction. In fact, the risk of sudden cardiac death is higher in patients with a non-Q-wave infarction than in patients with a Q-wave infarction. One possible reason for postinfarction arrhythmias is cardiac adrenergic denervation resulting from myocardial infarction. In this study we compared cardiac adrenergic innervation after non-Q-wave and Q-wave infarctions. Single-photon emission tomography using iodine-123 metaiodobentzylguanidine (MIBG) and technetium-99m sestamibi (MIBI) tracers were conducted in order to compare cardiac adrenergic denervation and myocardial perfusion in 12 patients with a non-Q-wave infarction and 15 patients with a Q-wave infarction. MIBG and MIBI defects were determined as regional uptake ≤30% of maximal myocardial activity. The size of MIBI defects calculated as a percentage of left ventricular mass was significantly smaller in patients with a non-Q-wave infarction than in patients with a Q-wave infarction (4%±3% vs 9%±7%, P〈0.05, respectively). According to the maximal serum creatine kinase activity, less myocardium was damaged in patients with a non-Q-wave infarction than in patients with a Q-wave infarction (502±436 IU/l vs 1878± 1265 IU/l, P〈0.001). In spite of this, the extent of MIBG defects was similar in patients with a non-Q-wave and patients with a Q-wave infarction (21%±18% vs 23%± 12%, respectively). In addition, the size of MIBG defect correlated with the infarct size (maximal creatine kinase activity) (r=0.52, P〈0.05) after a Q-wave infarction but not after a non-Q-wave infarction. In conclusion, despite a smaller infarct size in non-Q-wave infarct patients, the extent of cardiac adrenergic denervation was similar in patients with a non-Q-wave and patients with a Q-wave infarction. In addition, the extent of cardiac adrenergic denervation was related to the infarct size in patients with a Q-wave infarction but not in patients with a non-Q-wave infarction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002590000278
