Term
| How long are the first and second heart sounds? Which has a higher frequency? |
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Definition
| About 0.14s and 0.11s, the second sound (semilunar valves are more taut and vibrate for a shorter time, also arterial walls have higher elastic coefficient compared to ventricular chambers) |
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Term
| What is the audible range of heart sound frequency? |
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Definition
| Roughly 40 - 500 cycles/sec |
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Term
| During which phase is the third heart sound occasionally heard? |
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Definition
| The middle third of diastole (probably from oscillation of blood in ventricles after inrushing from the atria) |
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Term
| Describe the fourth heart sound (atrial heart sound) |
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Definition
| Sometimes recorded on a phonogram, weak and low frequency, occurs during atrial contraction from blood rushing into ventricles |
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Term
| What condition causes the greatest number of valvular lesions? What causes the condition? |
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Definition
| Antibodies formed in response to infection with group A hemolytic streptococci (Rheumatic fever). |
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Term
| What are the valves most affected by rheumatic heart? |
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Definition
| Mitral and aortic (due to higher pressure/trauma vs. the right side of the heart) |
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Term
| What is it called when valve leaflets adhere to one another so extensively that blood cannot flow through normally? |
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Definition
| Stenosis (stenosed valves) |
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Term
| What occurs when valve edges are so destroyed by scar tissue they cannot close as ventricles contract? |
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Definition
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Term
| Describe what happens in aortic stenosis, and describe its murmur |
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Definition
| Blood ejected through small fibrous opening, left ventricular pressure can get very high, creates nozzle effect during systole, severe turbulence of blood in root of aorta, causes harsh loud systolic murmur, can sometimes be palpated as a thrill |
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Term
| What happens during aortic regurgitation? Describe its murmur. |
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Definition
| During diastole, blood flows back from aorta into left ventricle, causing a "blowing," "squishing" diastolic murmur of relatively high pitch |
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Term
| What happens during mitral regurgitation? Describe its murmur. |
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Definition
| Blood flows backward through mitral valve into the left atrium during systole, causes high-frequency blowing/squishing sound. Left atrium is deep, so it transmits to the chest wall mainly through the apex. |
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Term
| Describe what happens during mitral stenosis and what sort of murmur it creates. |
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Definition
| Blood passes with difficulty through the stenosed mitral valve from left atrium into left ventricle. Large pressure differential does not develop (so murmur may be too weak and low pitched to hear at all). Murmur is not heard until middle third of diastole, when ventricle is partially filled, and a low rumbling murmur can sometimes be heard then. |
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Term
| In which phase does aortic stenosis murmur occur? |
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Definition
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Term
| In which phase does the murmur of mitral regurgitation occur? |
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Definition
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Term
| In which phase does the murmur of aortic regurgitation occur? |
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Definition
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Term
| In which phase does the murmur of mitral stenosis occur? |
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Definition
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Term
| Which valvular lesion causes the loudest murmurs? Weakest? |
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Definition
| Aortic stenosis, mitral stenosis |
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Term
| What happens to the net stroke volume output of the heart during both aortic stenosis and aortic regurgitation? |
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Definition
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Term
| What happens to the left ventricle to adapt to a seriously stenosed aortic valve? |
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Definition
| It hypertrophies, develops as much as 400 mm Hg intraventricular pressure at systolic peak. |
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Term
| What happens to the left ventricle to adapt to a severe aortic regurgitation? |
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Definition
| It hypertrophies, can eventually pump a stroke volume output of up to 250 ml (although as much as 3/4 will regurg back into ventricle) |
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Term
| What happens to the blood when valvular defects cause diminished output? |
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Definition
| Blood volume increases due to drop in arterial pressure and induced peripheral circulatory reflexes. Renal output drops, blood vol. and art. pressure increase. RBC mass increases due to tissue hypoxia. Together, venous return to heart increases, heart has to pump harder. |
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Term
| After a critical stage with aortic valve lesions, what happens? |
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Definition
| Left ventricle begins to dilate, cardiac output falls, blood dams up left atrium and the lungs. At mean left atrial pressure above 25 - 40 mm Hg, serious pulmonary edema appears. |
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Term
| Mitral stenosis and mitral regurgitation both accomplish the same thing: reducing the... |
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Definition
| net movement of blood from left atrium into left ventricle. |
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Term
| In mitral valvular disease, build-up of blood increases the pressure in which chamber? This leads to the development of... |
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Definition
| Left atrium, serious pulmonary edema. |
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Term
| Lethal pulmonary edema occurs at what left atrial pressure range? Why not sooner? |
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Definition
| 25-40 mm Hg, lung lymphatic vasculature enlarges and can carry fluid away rapidly |
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Term
| How does increased left atrial pressure affect the electrical conduction system of the heart? What abnormal rhythm can develop? |
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Definition
| It enlarges the chamber, increasing the distance of the electrical impulse, develops signal circus movements, atrial fibrillation usually occurs. |
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Term
| How does the body compensate for the effects of early mitral valve disease? |
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Definition
| Increase in blood volume, mainly through decreased renal output |
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Term
| What is the mechanism by which mitral valve disease causes change in the right side of the heart? |
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Definition
| Left atrial pressure rises, blood dams up in lungs, pulmonary edema causes pulmonary arteriolar constriction, systolic pulmonary arterial pressure increases, right ventricular pressure increases, right side of the heart hypertrophies to compensate for increased workload |
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Term
| Why are dynamic abnormalities of valvular lesions exacerbated by exercise? |
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Definition
| Large quantities of blood are returned to the heart from the peripheral circulation |
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Term
| For pts with aortic valvular lesions, exercise can cause... |
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Definition
| acute left ventricular failure followed by acute pulmonary edema |
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Term
| in pts with mitral valvular disease, exercise can cause so much damming of blood in the lungs that... |
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Definition
| serious or lethal pulmonary edema can ensue in as little as 10 minutes |
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Term
| Even in mild to moderate valvular disease, cardiac reserve diminishes. What does this mean (with regard to exercise)? |
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Definition
| The cardiac output does not increase as much as it should. |
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Term
| At what level does coarctation of the aorta often occur? What does this cause? |
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Definition
| At the level of the diaphragm, arterial pressure in the upper body >> lower part of body |
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Term
| In the FETUS, pulmonary arterial pressure is ______ , aortic pressure is ______, causing blood to flow through the _____________ and bypass the ______. |
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Definition
| HIGH, LOW, ductus arteriosus, lungs. |
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Term
| What changes occur in the lungs and vasculature when a baby is born and begins to breathe? |
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Definition
| Lungs inflate, pulmonary vasculature resistance decreases, aortic pressure rises, blood begins to flow backward through ductus from aorta into pulmonary artery |
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Term
| Why does the ductus arteriosus close? |
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Definition
| Oxygen concentration of blood flowing through it is much higher than before, this constricts the muscle in the arterial wall |
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Term
| Patent ductus arteriosus occurs in 1/______ babies. |
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Definition
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Term
| What happens to the relative pressures in the pulmonary artery and the aorta as a baby grows older? What structural change does this cause in a patent ductus arteriosus? |
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Definition
| The pressure differential between the aorta (high) and pulmonary artery (low) increases, this increases the diameter of the ductus |
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Term
| What are the major clinical effects of patent ductus? What structural change occurs in the heart? |
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Definition
| Decreased cardiac and respiratory reserve, causes weakness and fainting during exercise, hypertrophy of the heart |
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Term
| In a patent ductus, high pressures in the pulmonary vessels caused by excess flow through the lungs leads to... |
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Definition
| pulmonary congestion and edema, progressively more severe with age |
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Term
| Most patients with uncorrected patent ductus arteriosus die from heart disease within the ages of ___ to ___. |
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Definition
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Term
| At an age of 1 - 3 years, what sort of abnormal heart sound occurs in pts with a patent ductus arteriosus? |
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Definition
| Harsh, blowing murmur that is more intense during systole, called a machinery murmur |
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Term
| Patent ductus arteriosus is a ____ -to- _____ shunt. |
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Definition
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Term
| Tetralogy of Fallot is a ____ -to- _____ shunt. |
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Definition
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Term
| Tetralogy of Fallot is the most common cause of _________ because most of the blood bypasses the _______. |
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Definition
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Term
| What are the 4 abnormalities of the TofF? |
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Definition
| 1- aorta comes from right ventricle or overrides a hole in the ventricular septum, 2- pulmonary artery is stenosed, 3 - blood from left ventricle flows through hole to right ventricle or into aorta overriding the hole, 4 - enlarged right ventricle |
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Term
| What is the major problematic effect of the TofF? |
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Definition
| Shunting of blood past the lungs without becoming oxygenated (as much as 75%) |
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Term
| Diagnosis of TofF is based on what 4 factors? |
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Definition
| 1 - cyanosis, 2 - high systolic pressure measured in right ventricle, 3 - x-ray changes showing enlarged right ventricle, 4 - angiograms showing abnormal blood flow |
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Term
| What is the treatment for TofF? How does it change life span? |
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Definition
| Surgical correction, from 3-4 to 50 or more years |
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Term
| What are the primary causes of congenital heart abnormalities? |
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Definition
| Viral infection of mom during first trimester, hereditary |
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Term
| What special machines are needed during repair of intracardiac defects? What do they accomplish? |
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Definition
| artificial heart-lung machines, extracorporeal circulation |
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Term
| What are the 4 methods for oxygenating blood extracorporeally? |
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Definition
| 1 - bubbling O2 through blood and removing bubbles, 2 - dripping blood over plastic sheets in presence of O2, 3 - passing blood over rotating discs, 4 - passing blood thru thin membranes or tubes permeable to O2 and CO2 |
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Term
| What problems occur with the machinery needed during open heart surgeries? |
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Definition
| hemolysis, clots, bubbles, emboli of antifoam agent, needing large quantities of blood to prime the machine, needing to use heparin which interferes with hemostasis during surgery |
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Term
| What are the two theories behind the mechanism of heart hypertrophy? |
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Definition
| Increased strength of contraction causes hypertrophy, or increased metabolic rate of muscle causes it |
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