[Biologist's view on diastolic dysfunction].

B Swynghedauw

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PubMed · 1835366

[Biologist's view on diastolic dysfunction].

B Swynghedauw

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Abstract

Modern biology provides satisfactory explanations for the abnormalities of the different phases of relaxation and diastole. Ventricular filling depends on three factors: active relaxation; the only factor is the concentration of ATP which has to re-increase. This requires elimination of the cytoplasmic calcium which activates ATP-ase by the Ca2+ ATPase of the sarcoplasmic reticulum and the Na+/Ca2+ pump. In hypertrophy, the concentration of the first and the activity of the second are decreased; passive wall compliance, which depends on the quantity and quality of parietal collagen. This factor is partially regulated in the myocardium by the concentration of aldosterone and angiotensin II; atrial contraction, which depends on the size of the atria and their isomyosine content. This changes in atrial overload to a slow form of myosine, one of the mechanisms of adaptation.

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Calcium Calcium-Transporting ATPases Compliance Diastole Heart Humans Myocardial Contraction Myocardium Myosins Journal Article

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B Swynghedauw. 1991. [Biologist's view on diastolic dysfunction].. https://pubmed.ncbi.nlm.nih.gov/1835366/

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