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Effects of hyaluronidase and hydrocortisone on myocardial necrosis after coronary occlusion
Insights
Hydrocortisone and hyaluronidase significantly reduced myocardial infarct size in dogs. Hyaluronidase also improved electrocardiographic changes in human patients with myocardial infarction.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Myocardial infarction (MI) is a leading cause of mortality.
- Effective treatments to limit infarct size and improve patient outcomes are crucial.
Purpose of the Study:
- To investigate the efficacy of hydrocortisone and hyaluronidase in reducing myocardial infarct size.
- To evaluate the clinical effects of hyaluronidase on electrocardiographic changes in patients with MI.
Main Methods:
- Anesthetized dogs underwent coronary artery occlusion, followed by administration of hydrocortisone or hyaluronidase.
- Clinical study involved two groups of MI patients treated with hyaluronidase and two control groups.
Main Results:
- Hydrocortisone and hyaluronidase administration significantly reduced myocardial infarct size in dogs, assessed by creatine phosphokinase activity and histology.
- Hyaluronidase treatment in human patients led to a faster reduction in S-T segment elevations.
- Early hyaluronidase treatment (within 4 hours) showed a trend towards lower Q wave incidence and less R wave reduction.
Conclusions:
- Both hydrocortisone and hyaluronidase demonstrate protective effects against myocardial infarction in animal models.
- Hyaluronidase shows promise as a therapeutic agent in managing acute myocardial infarction in humans, particularly when administered early.
Abstract:
In anesthetized open chest dogs, hydrocortisone (50 mg/kg body weight administered 30 minutes after occlusion and 25 mg/kg 12 hours later) substantially reduced the size of myocardial infarcts, as reflected by both myocardial creatine phosphokinase activity and histologic appearance 24 hours later. Similarly, hyaluronidase, which increases diffusion through the extracellular space and presumably facilitates delivery of substrate to ischemic cells, also reduced the extent of myocardial necrosis after coronary occlusion in the dog. In view of the salutary effects of hyaluronidase and the absence of serious side effects, this agent was administered clinically to two groups of patients, who were compared with two groups of untreated control subjects. Hyaluronidase (500 National Formulary units/kg X 8) was shown to result in a significantly more rapid reduction in the magnitude and the extent of precordial S-T segment elevations, and in patients treated within 4 hours a tendency to a lower incidence rate of Q waves and a smaller reduction of R waves.