Load-sensitive diastolic relaxation in hypertrophied left ventricles
| Autor: | André A. Charlier, Julian Donckier, Hubert Pouleur, Henri Van Mechelen, W. Hayashida |
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| Rok vydání: | 1998 |
| Předmět: |
medicine.medical_specialty
Hypertension Renal Enalaprilat Physiology Diastole Hemodynamics Tetrazoles Angiotensin-Converting Enzyme Inhibitors Blood Pressure Muscle hypertrophy Dogs Physiology (medical) Internal medicine medicine Animals cardiovascular diseases Antihypertensive Agents biology Relaxation (psychology) Chemistry Angiotensin II Fissipedia Imidazoles biology.organism_classification Endocrinology Blood pressure Cardiology Hypertrophy Left Ventricular Cardiology and Cardiovascular Medicine medicine.drug |
| Zdroj: | The American journal of physiology. 274(2) |
| ISSN: | 0002-9513 |
| Popis: | We studied effects of enalaprilat and L-158,809, an angiotensin II type-1 receptor antagonist, on left ventricular (LV) diastolic relaxation in 11 normal control dogs and 16 LV hypertrophied (LVH) dogs with perinephritic hypertension. At baseline, LV systolic and end-diastolic pressures and end-systolic elastance were increased in the LVH group (all P < 0.01 vs. the control group). LV relaxation time constant was also prolonged ( P < 0.01), suggesting impaired LV diastolic relaxation in this model of LVH. Before and after the administration of enalaprilat (0.25 mg/kg) and L-158,809 (0.30 mg/kg), LV relaxation was assessed over a wide range of LV loading conditions during vena caval occlusion. LV relaxation time constant was insensitive to load reduction in the control group, which was not affected by enalaprilat or L-158,809. In contrast, LV unloading caused a significant prolongation of the relaxation time constant in the LVH group. This load-sensitive LV relaxation abnormality was significantly improved by enalaprilat or L-158,809. These results support the concept that angiotensin II is involved in the pathogenesis of diastolic dysfunction in pressure-overloaded LVH and also suggest that angiotensin-converting enzyme inhibitors and angiotensin II type-1 receptor antagonists are potentially beneficial in the treatment of the hypertrophied heart. |
| Databáze: | OpenAIRE |
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