Cardiac Vocabulary: Part 1 Flashcards
Cardiovascular Disease
Disease affection the heart, peripheral blood vessels, or both
Coronary Heart Disease
A type of cardiovascular disease, the single largest killer of Americans.
Electrocardiogram
The graphic recording of the heart’s electrical activity. It may be displayed either on paper o on an oscilloscope.
Artifact
Deflection on the ECG produced by factors other than the heart’s electrical activity.
Einthoven’s triangle
The triangle around the heart formed by the bipolar limb leads
Augmented limb leads
Another term for unipolar limb leads, reflecting the fact that the ground lead is disconnected, which increased the amplitude of deflection on the ECG tracing. Includes leads aVR, aVL, aVF
Unipolar Limb Leads
Electrocardiogram leads applied to the arms and legs, consisting of on polarized (positive) electrode and a non polarized reference point that is created by the ECG machine combining two additional electrodes; also called augmented limb leads; leads aVR, aVL, and aVF.
Precordial (chest) leads
Electrocardogram leads applied to the chest in a pattern that permits a view of the horizontal plane of the heart; leads V1-V6.
Prolonged QT interval
QT interval greater than .44 seconds.
Refractory period
The period of time when myocardial cells have not yet completely repolarized and cannot be stimulated again.
Absolute Refractory Period
The period of the cardiac cycle when stimulation will not produce any depolarization whatsoever.
Relative refractory period
The period of the cardiac cycle when a sufficiently strong stimulus may produce depolarization.
Dysrhythmia
Any deviation from the normal electrical rhythm of the heart
Arrhythmia
The absence of cardiac electrical activity; often used interchangeably with dysrhythmia.
Non-compensatory pause
Pause following an ectopic beat where the SA node is depolarized and the underlying cadence of the hear is interrupted.
Bruit
The sound of turbulent blood flow through ha vessel usually associated with atherosclerotic disease.
Compensatory Pause
The pause following an ectopic beat where the SA node is unaffected and the cadence of the heart is uninterrupted.
Interpolated Beat
A PVC that falls between two sinus beats without effectively interrupting the rhythm.
Coupling Interval
Distance between the preceding beat and the PVC
Aberrant Conduction
Conduction of the electrical impulse through the heart’s conductive system in an abnormal fashion.
Bundle Branch Block
A kind of interventricular heart block in which conduction through either the right or left bundle branches is blocked or delayed.
Bundle of Kent
An accessory AV conduction pathway that is thought to be responsible for the ECG findings of preexcitation syndrome.
Ejection Fraction
When the ventricles of the heart contract and eject. about two thirds of the blood they contain.
Stroke Volume
The amount of blood ejected from the heart
Preload
The end-diastolic volume and influences the ford of the next contraction because of the stretch it exerts.
Starling’s Law
Law of he heart that states that the more myocardial muscle is stretched, the greater its force of contraction will be.
Afterload
The resistance against which hthe heart muscle must pump.
Cardiac Output formula
Stroke volume x heart rate= Cardiac Output
Chronotropy
Heart rate
Inotropy
Contractile Strength
Dromotropy
Rate of nervous impulse conduction
What are the five electrolytes that effect the heart?
Sodium (Na+), Calcium (Ca++), Potassium (K+), Chloride (CT-), and Magnesium (Mg++)
How does sodium play a role in the heart?
In depolarizing the myocardium
How does calcium play a role in the heart?
Takes part in myocardial depolarization and myocardial contraction
How does potassium play a role in the heart?
Influences repolarization
Intercalated discs
Connect cardiac muscle fibers and conduct electrical impulses quickly from one muscle fiber to the next.
