Chapter 7 Flashcards
cardiovascular
Why is the heart considered to be two pumps functionally?
The right atrium and right ventricle serve functionally as one pump for ejecting blood to the lungs, and the left atrium and left ventricle pump blood to the systemic circulation.
Cardiac cells are connected by intercalated disks and a fusion of cell membranes to form a ____
Syncytium (interconnected mass)
Depolarization of cardiac cells is characterized by a rapid influx of ___ ions, a slower influx of ____ ions, and the outflow of ___ ions.
Sodium (Na+)
Calcium (Ca2+)
Potassium (K+)
A relatively long ____ is important to cardiac cells to prevent a constant state of contraction from recycling impulses.
Refractory period
Define chronotropic and inotropic effects in relation to the heart.
Chronotropic refers to the rate of contraction, whereas intotropic refers to the force or strength of contraction.
Define preload and afterload in relation to the pumping mechanism of the heart.
Preload is the volume of blood in the ventricles at the end of diastole (the amount of blood that must be pumped out). Afterload is the resistance in the arteries that the ventricle must overcome to pump blood.
List the 4 basic compensatory mechanisms of the cardiovascular system.
Increasing the heart rate, increasing the stroke volume, increasing the efficiency of the heart muscle, and heart enlargement
List 5 objectives of treatment for heart failure
Control rhythm disturbances, maintain or increase cardiac output, relieve fluid accumulations, increase the oxygenation of blood, and provide oxygen/sedatives.
List 4 beneficial effects and one potential toxic effect of the use of the cardiac glycosides.
Beneficial effects include improved cardiac contractility, decreased heart rate, antiarrhythmic effect, and decreased signs of dyspnea.
Toxic effect is vomiting
Catecholamines such as epinephrine are used in veterinary cardiology primarily for…..
Stimulation of cardiac contraction in cardiac arrest
List 5 factors that may predispose the heart to arrhythmias.
conditions that cause hypoxia;
electrolyte imbalances;
increased levels or sensitivity to catecholamines;
certain drugs such as digitalis, barbiturates, and others;
and cardiac trauma or disease
List 6 categories of antiarrhythmic drugs and give an example of each
Class 1A: quinidine Class 1B: lidocaine Class 1C: flecainide Class II : propranolol Class III : bretylium Class IV : diltiazem
List 4 vasodilator drugs and classify each as arteriolar dilator, venodilator, or mixed.
- Hydralazine: arteriolar dilator
- Nitroglycerin: venodilator
- Prazosin: mixed
- Enalapril: mixed
Why is lasix sometimes called loop diuretic?
Lasix is called a loop diuretic because it inhibits reabsorption of sodium in the loops of Henle.
The use of many diuretics can lead to a dangerous loss of what electrolytes?
Potassium
List 5 ancillary methods of treatment for cardiovascular disease.
Bronchodilation, oxygen therapy, sedation, aspiration, and centesis
____ is characterized by the rapid influx of sodium ions into the cell through channels, the slower influx of calcium ions, and the outflow of potassium ions.
Depolarization
The amount of blood that the heart is capable of pumping per minute is called ___
cardiac output
_____ results when the pumping ability of the heart is impaired to the extent that sodium and water are retained in an effort to compensate for inadequate cardiac output.
Congestive heart failure
ACE causes the conversion of ______ to _____
Angiotensin I to Angiotensin II
Nitroglycerin is supplied as an ointment. List the precautions that should be taken when applying.
Wear gloves, rotate application sites, do not pet the animal at the application site, measure the dosage in inches, and contact the veterinarian is a rash appears at the application site.
What diuretic is used most commonly in the treatment of heart failure?
Lasix
What is hypokalemia?
An abnormally low potassium level in the blood
What are the primary goals of the dietary management of heart disease?
The primary goals are
(1) sodium restriction
(2) maintenance of good body weight and
condition (reduction of obesity or cachexia). In
some instances, specific nutrient deficiencies,
concurrent disease, and/or electrolyte disorders
may need to be addressed.
List 3 effects of administration of catecholamines:
- Increased force of contracion
- An increase in blood pressure
- Elevated blood glucose levels
The heart is a ___ -chambered pump that is responsible for moving blood through vascular system.
4
__ is a faster than normal heart rate.
Tachycardia
When situations cause spontaneous depolarization of cardiac muscle or abnormalities of the conduction system, _____ may occur.
arrhythmia
Which of the following is not a way by which the cardiovascular system may increase its output during times of need, such as during athletic performance or to compensate for cardiac disease?
A. Decreasing heart rate to such an extent that the myocardium is protected from damage caused by the increased workload
B. Increasing the stroke volume
C. Increasing the efficiency of the heart muscle
D. Physiologic heart enlargement; the heart is composed of muscle that responds to work by increasing its size and becoming stronger
A. decreasing heart rate to such an extent that the myocardium is protected from damage caused by the increased workload
Congestive heart failure (CHF) results when the pumping ability of the heart is impaired to the extent that Na and H2O are retained in an effort to compensate for inadequate cardiac output, It is associated with….
- exercise intolerance
- pulmonary edema
- ascites
Digitalis is a(an) ____. It is obtained from the dried leaves of the plant Digitalis purpurea.
Cardiac glycoside
Quinidine is an alkaloid that is obtained from cinchona plants or is prepared from quinine. It is used to treat ventricular tachycardia, and atrial fibrillation. Quinidine doses must be ___ in patients who are being treated concurrently with digoxin.
decreased
Gloves do not have to be worn when applying nitroglycerin. T/F
false
Concurrent use of nonsteriodal antiinflammatory drugs may __ the effectiveness of captopril.
decrease
Furosemide may cause ___ in patients
hypokalemia
