Term
compensatory mechanisms of cardiac system |
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Definition
. Increasing the heart rate. Increasing the rate of contraction increases cardiac output up to the point at which the rate is so fast that there is inadequate time for ventricular filling. 2. Increasing the stroke volume. Up to a point, an increased force of contraction results in an increase in the amount of blood that is pumped. 3. Increasing the efficiency of the heart muscle. 4. Cardiac remodeling. The heart is composed of muscle that responds to work by increasing its size and becoming stronger. This change usually precedes the development of heart failure signs by months or years. |
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Term
objectives of CV treatment |
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Definition
Control rhythm disturbances
maintain or decrease cardiac output
•Relieve fluid accumulations
Increase the oxygenation of the blood
Ancillary treatment •Narcotics/sedatives •Oxygen |
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Term
use of drugs that improve the strength of contraction is that the heart. |
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Definition
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Term
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Definition
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Term
effects of cardiac glycosides |
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Definition
Effects: (1) improved cardiac contractility, (2) decreased heart rate, (3) antiarrhythmic effects, and (4) decreased signs of dyspnea. |
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Term
categories of antiarrhythmic drugs |
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Definition
1.Class IA includes quinidine, procainamide, and others. Class IB includes lidocaine, tocainide, and mexiletine. Class IC includes flecainide and encainide. 2.Class II includes the beta-adrenergic blockers (propranolol). 3.Class III includes bretylium and amiodarone. 4.Class IV includes the calcium channel blockers (verapamil, nifedipine, amlodipine, and diltiazem). |
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Term
cardiac dz that respond to drugs |
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Definition
valvular
arrhythmias
myocardial
congenital |
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Term
stage I signs and treatment |
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Definition
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Term
stage II signs and treatment |
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Definition
cough
treat: restrict sodium, diuretic, bronchodilator |
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Term
stage III signs and treatment |
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Definition
cough, reduced exercise tolerance
treat: sodium restriction, digitalis, diuretic, vasodilators |
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Term
stage IV and and treatment |
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Definition
dyspnea at rest
treat: oxygen, diuretics, sedation, vasodilators, other |
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Term
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Definition
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Term
cardiac glycoside category |
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Definition
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Term
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Definition
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Term
positive ionotropic drug classes |
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Definition
cardiac glycosides (digitalis)
catecholamines (epinephrine) |
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Term
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Definition
glycosides (digitalis) catecholamines (epinephrine) antiarrhythmic (6 classes) beta adrenergic blockers (propranolol) vasodilators diuretics (furosemide) |
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Term
antiarrythmic drug categories and example |
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Definition
Class IA includes quinidine, procainamide, and others.
Class IB includes lidocaine, tocainide, and mexiletine.
Class IC includes flecainide and encainide.
2.Class II includes the beta-adrenergic blockers (propranolol).
3.Class III includes bretylium and amiodarone.
4.Class IV includes the calcium channel blockers (verapamil, nifedipine, amlodipine, and diltiazem). |
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Term
antiarrythmic drug categories and example |
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Definition
Class IA includes quinidine, procainamide, and others.
Class IB includes lidocaine, tocainide, and mexiletine.
Class IC includes flecainide and encainide. not used in vet med
2.Class II includes the beta-adrenergic blockers (propranolol).
3.Class III includes bretylium and amiodarone. not used in vetmed
4.Class IV includes the calcium channel blockers (verapamil, nifedipine, amlodipine, and diltiazem). |
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Term
adverse effects of antiarrythmic drugs |
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Definition
Anorexia, vomiting, diarrhea, weakness, and laminitis (horses), hypotension, drowsiness, depression, ataxia, and muscle tremors, bradycardia, syncope, worsening of heart failure, lethargy, bronchospasm, tachycardia, pulmonary edema, and depression |
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Term
how do vasodilators work? |
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Definition
Vasodilator drugs act by dilating arteries (arteriolar dilator), veins (venodilator), or both (combined vasodilator). Dilatory activity may be brought about by direct action on vessel smooth muscle, through blockage of sympathetic stimulation, or by preventing conversion of angiotensin I to angiotensin II. Dilation of constricted arteries tends to decrease the afterload and improve cardiac output. The preload is also reduced because of pooling of blood in dilated veins. |
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Term
adverse effects of vasodilators |
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Definition
hypotension syncope vomiting diarrhea sodium and water retention tachycardia |
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Term
how do ace inhibitiors work? |
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Definition
prevent the conversion of angiotensin I to angiotensin II by inhibiting ACE. They are combined vasodilators that produce mild preload and significant afterload reduction. |
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Term
adverse effects of ace inhibitiors |
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Definition
hypotension azotemia vomiting diarrhea hyperkalemia others |
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Term
adverse effects of diuretics |
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Definition
low blood potassium (hypokalemia) dehydration low blood sodium (hyponatremia) ototoxicity (cats) weakness shock. |
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Term
why do we restrict sodium in diets? |
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Definition
increased sodium levels in the body lead to water retention, increased plasma volume, and exacerbation of the clinical signs of heart failure. |
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Term
ancillary treatments in heart dz |
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Definition
bronchodilator oxygen aspirin sedation thoracentesis or abdominocentesis |
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Term
The resistance (pressure) in arteries that must be overcome to empty blood from the ventricle. |
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Definition
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Term
A variation from the normal rhythm. |
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Definition
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Term
The ability of cardiac muscle to generate impulses. |
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Definition
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Term
Bradycardia associated with an irregularity of heart rhythm. |
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Definition
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Term
Change in the size, shape, structure, and physiology of the heart due to damage to the myocardium |
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Definition
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Term
Neutralizing of the polarity of a cardiac cell by an inflow of sodium ions. results in contraction of the cardiac cell and renders it incapable of further contraction until repolarization occurs |
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Definition
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Term
The volume of blood in the ventricles at the end of diastole. |
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Definition
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Term
Contraction of the ventricles without a corresponding contraction of the atria. PVCs arise from an irritable focus or foci in the ventricles. |
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Definition
premature ventricular contraction |
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Term
The return of the cell membrane to its resting polarity after depolarization. |
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Definition
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Term
The amount of blood ejected by the left ventricle with each beat. |
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Definition
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Term
Tachycardia associated with an irregularity in normal heart rhythm. |
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Definition
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Term
kidneys react to the lowered blood pressure, which causes the release of aldosterone. The aldosterone causes the kidneys to reabsorb more water and retain sodium (salt), which helps to raise blood pressure. In the short term, the absorbed water and sodium are helpful. But in the long term, the ailing heart now has to deal with pumping more fluid (from the reninangiotensin system) into smaller blood vessels (which have greater resistance). The compensatory mechanisms have now added more work for an already overburdened heart. |
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Definition
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Term
arteriolar dilator that acts directly on smooth muscle in the arterial wall. Sometimes a diuretic is used with it, because it may activate the renin-angiotensin system and cause water retention. |
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Definition
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Term
venodilator that reduces preload to the |
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Definition
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Term
combined dilator that acts by blocking alpha-1 adrenergic receptor sites. The venodilation reduces preload and the arteriolar dilation reduces afterload. Side effects include hypotension, vomiting, and diarrhea. |
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Definition
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Term
are combined vasodilators that act by blocking the renin-angiotensin system and are often used concurrently with digoxin and lasix |
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Definition
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