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  2. Cardiac cycle - Wikipedia

    en.wikipedia.org/wiki/Cardiac_cycle

    Cardiac (ventricular) systole: Both AV valves (tricuspid in the right heart (light-blue), mitral in the left heart (pink)) are closed by back-pressure as the ventricles are contracted and their blood volumes are ejected through the newly-opened pulmonary valve (dark-blue arrow) and aortic valve (dark-red arrow) into the pulmonary trunk and ...

  3. Systole - Wikipedia

    en.wikipedia.org/wiki/Systole

    The time variable for the right systolic cycle is measured from (tricuspid) valve-open to valve-closed. The contractions of atrial systole fill the left ventricle with oxygen-enriched blood through the mitral valve; when the left atrium is emptied or closed, left atrial systole is ended and ventricular systole is about to begin. The time ...

  4. Heart valve - Wikipedia

    en.wikipedia.org/wiki/Heart_valve

    During ventricular systole, pressure rises in the left ventricle and when it is greater than the pressure in the aorta, the aortic valve opens, allowing blood to exit the left ventricle into the aorta. When ventricular systole ends, pressure in the left ventricle rapidly drops and the pressure in the aorta forces the aortic valve to close.

  5. Mitral valve - Wikipedia

    en.wikipedia.org/wiki/Mitral_valve

    The mitral valve and the tricuspid valve are known as the atrioventricular valves because they lie between the atria and the ventricles. [1] In normal conditions, blood flows through an open mitral valve during diastole with contraction of the left atrium, and the mitral valve closes during systole with contraction of the left ventricle. The ...

  6. Isovolumetric contraction - Wikipedia

    en.wikipedia.org/wiki/Isovolumetric_contraction

    The net result is that, while contraction causes ventricular pressures to rise sharply, there is no overall change in volume because of the closed valves. The isovolumetric contraction phase lasts about 0.05 seconds, [ 1 ] but this short period of time is enough to build up a sufficiently high pressure that eventually overcomes that of the ...

  7. Cardiac physiology - Wikipedia

    en.wikipedia.org/wiki/Cardiac_physiology

    The semilunar valves close to prevent backflow into the heart. Since the atrioventricular valves remain closed at this point, there is no change in the volume of blood in the ventricle, so the early phase of ventricular diastole is called the isovolumic ventricular relaxation phase, also called isovolumetric ventricular relaxation phase. [1]

  8. Tricuspid valve - Wikipedia

    en.wikipedia.org/wiki/Tricuspid_valve

    The tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, at the superior portion of the right ventricle.The function of the valve is to allow blood to flow from the right atrium to the right ventricle during diastole, and to close to prevent backflow (regurgitation) from the right ventricle into the right atrium during right ventricular ...

  9. Heart sounds - Wikipedia

    en.wikipedia.org/wiki/Heart_sounds

    Normally A 2 precedes P 2 especially during inspiration where a split of S 2 can be heard. It is caused by the closure of the semilunar valves (the aortic valve and pulmonary valve) at the end of ventricular systole and the beginning of ventricular diastole. As the left ventricle empties, its pressure falls below the pressure in the aorta ...