Related Experiment Videos
Influence of enoximone and UDCG-115 on coronary hemodynamics in idiopathic dilated cardiomyopathy
C Holubarsch1, G Hasenfuss, W H Heiss
1Department of Cardiology, University of Freiburg, Federal Republic of Germany.
Insights
Idiopathic dilated cardiomyopathy patients show normal resting coronary hemodynamics. Phosphodiesterase inhibitors like enoximone and UDCG-115 improve coronary oxygen supply-demand ratio in these patients.
Area of Science:
- Cardiology
- Cardiovascular Physiology
Background:
- Idiopathic dilated cardiomyopathy (IDCM) affects myocardial function.
- Understanding coronary hemodynamics in IDCM is crucial for treatment.
Purpose of the Study:
- To compare resting coronary hemodynamics in IDCM patients versus healthy controls.
- To evaluate the effects of phosphodiesterase inhibitors on coronary hemodynamics in IDCM.
Main Methods:
- Utilized the argon method to assess coronary hemodynamics in 24 IDCM patients and 17 healthy controls.
- Administered enoximone and UDCG-115 intravenously to IDCM patients to measure changes in myocardial oxygen consumption (MVO2) and oxygen supply-demand ratio.
Main Results:
- No significant differences in resting myocardial blood flow, MVO2, or oxygen supply-demand ratio were found between IDCM patients and controls.
- Enoximone showed a non-significant 8% decrease in MVO2, while UDCG-115 caused a significant 26% decrease in MVO2.
- Both drugs significantly increased the oxygen supply-demand ratio in IDCM patients.
Conclusions:
- Resting coronary hemodynamics per unit of myocardium are comparable between normal individuals and those with IDCM.
- Phosphodiesterase inhibitors demonstrate a beneficial effect on coronary hemodynamics by enhancing the oxygen supply-demand ratio in IDCM.
Abstract:
Coronary hemodynamics were studied in 24 patients with idiopathic dilated cardiomyopathy and in 17 patients without any significant heart disease under resting conditions using the argon method. Neither myocardial blood flow normalized for 100 g muscle tissue nor myocardial oxygen consumption per minute (MVO2) or oxygen supply-demand ratio were different between these 2 groups of patients. When enoximone (1 to 2 mg/kg body weight) was given intravenously in patients with idiopathic dilated cardiomyopathy, myocardial oxygen consumption decreased by only 8% (difference not significant), whereas a significant (p less than 0.05) 26% decrease of myocardial oxygen consumption was observed after UDCG-115 (1.25 mg/hour intravenously). However, with both substances the oxygen supply-demand ratio significantly increased from 1.46 +/- 0.10 to 1.57 +/- 0.20 (p less than 0.025; enoximone) and from 1.40 +/- 0.08 to 1.56 +/- 0.19 (p less than 0.05; UDCG-115), respectively. It is concluded from these data that (1) resting coronary hemodynamics related to a unit of myocardium are not different between normal and idiopathic dilated cardiomyopathy, and (2) phosphodiesterase inhibitors exert beneficial effects on coronary hemodynamics by improving the oxygen supply-demand ratio.