The influence of atrial contraction and mitral valve mechanics on ventricular filling
| Autor: | Andrew G. Morrow, R. Darryl Fisher, Sewell H. Dixon, Stanton P. Nolan |
|---|---|
| Rok vydání: | 1969 |
| Předmět: |
Mitral regurgitation
medicine.medical_specialty Contraction (grammar) medicine.diagnostic_test business.industry Blood flow medicine.anatomical_structure Mitral valve Internal medicine Heart rate cardiovascular system Cardiology Medicine cardiovascular diseases Atrium (heart) medicine.symptom Cardiology and Cardiovascular Medicine business Electrocardiography Muscle contraction |
| Zdroj: | American Heart Journal. 77:784-791 |
| ISSN: | 0002-8703 |
| DOI: | 10.1016/0002-8703(69)90412-8 |
| Popis: | Instantaneous blood flow across the normal mitral valve was studied in calves. Heart rate and atrial timing varied, allowing an assessment of the relative importance of atrial contraction to ventricular filling and to mitral valve closure. Results were: (1) The pattern of flow varied with heart rate and P-R interval; (2) at normal heart rates six phases of mitral valve flow were identified, and they defined the dynamics of the atrium and mitral valve; (3) a properly timed atrial contraction can augment ventricular filling by 20 per cent; (4) the contribution of atrial contraction to ventricular filling varied with its timing and with heart rate; (5) the mitral valve closed without regurgitation during sinus or nodal rhythm; (6) premature ventricular contractions could produce mitral regurgitation, but the volume was negligible; (7) the major role of atrial contraction is the augmentation of left ventricular filling and not the prevention of mitral regurgitation. |
| Databáze: | OpenAIRE |
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