Term
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Definition
5L/min
Same as amount of blood in CV system |
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Term
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Definition
Both atria and ventricles are at rest. Pulmonary and aortic valves (small, high pressure valves) are closed since pressure in aorta and pulmonary trunk>pressure in ventricles.
1. Atria fill with blood, pressure in atria>ventricles.
2. AV valves (low pressure valves) open and blood moves into ventricles. |
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Term
| Pathological components of heart |
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Definition
| Disease most likely occurs in the valves, the pumps, or the electrical components. |
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Term
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Definition
1. Atria contract due to depolarization from SA node.
2. Ventricles actively fill with blood through open AV nodes.
Results in completion of ventricular filling, pulmonary and aortic valve remain closed. |
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Term
| Early ventricular systole events |
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Definition
1. Ventricles contract due to depolarization from AV node to bundle of His.
2. Contraction starts at apex to base.
3. During contraction, ventricular pressure increases, becomes greater than atrial pressure. This shuts AV valves and creates S1 heart sound.
4. Pulmonary and aortic valves remain closed until pressure in the ventricles is greater than blood pushing down on semilunar valves (isovolumetric contraction). |
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Term
| Late ventricular systole events |
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Definition
1. Ventricles continue with isovolumentric contraction until ventricular pressure exceeds pressure of blood pushing down on aortic and pulmonary valves.
2. When pressure in ventricals exceed pressure in semilunar valves, the valves pop open and a bolus of blood ejects through.
3. During this time, the AV valves are shut and the atria fill with blood. |
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Term
| Ventricular diastole events |
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Definition
1. Ventricles repolarize and relax, causing a drop in ventricular pressure. 2. Causes aortic and pulmonary valve to close, producing S2 heart sound. 3. AV valves remain closed as long as ventricular pressure exceeds atrial pressure (isovolumetric relaxation). 4. When ventricular pressure
<atrial pressure, then AV valves open. |
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Term
|
Definition
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Term
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Definition
>25%
May require heart transplant |
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Term
| Action potential steps in contractile cardiac cell |
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Definition
1. Resting potential determined by K permeability.
2. Initial depolarization triggers opening of Na channels, which hyperpolarizes cell.
3. Na channels close and K channels start opening.
4. Sustained depolarization provided by Ca L channels, which also trigger CICR.
5. Repolarization occurs when Ca L channels close and even more K channels open. |
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Term
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Definition
| Determined by how long Ca L channel stays open. Influx of extracellular Ca triggers CICR (80% intracellular Ca, 20% extracellular). |
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Term
| Action potential in atrial cardiac cells |
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Definition
| Similar to ventricular cell action potential, but with less sustained depolarization for less forceful contraction. Atrial cells are designed to have less forceful contraction to avoid blood regurgitation into SVC and IVC. |
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Term
| Action potential in SA node. |
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Definition
| Cells have gradual decay of resting potential caused by Na leak channels called funny channels. Initial depolarization by funny channels causes Ca to rush into cell, causing the action potential upstroke. GIRK channels then open to repolarize the cell. Cells don't have all or nothing response due to funny channels, therefore, funny channels can be modulated to alter HR. |
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Term
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Definition
| Slow conduction time, allows for atria to fill ventricles fully. |
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Term
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Definition
1. P wave
2. QRS complex
3. T wave
4. PR Interval
5. QT interval
Atrial repolarization buried in QRS complex, can't see. |
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Term
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Definition
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Term
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Definition
| Ventricular depolarization |
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Term
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Definition
| Ventricular depolarization |
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Term
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Definition
| From atrial depolarization to Ventricular depolarization |
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Term
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Definition
| Between ventricular depolarization and repolarization. |
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