Lab & Diag II Exam 2

NSR

Interpretation?

Sinus arrhythmia

Interpretation?

Sinus tachycardia

Interpretation?

Sinus bradycardia

Interpretation?

SR c PAC (complex 3)

Interpretation?

SR c sinus pause/arrest

Interpretation?

SR c sinus block

Interpretation?

Wandering Atrial Pacemaker

Interpretation?

Multifocal atrial tachycardia

Interpretation?

Atrial Fibrillation

Interpretation?

Atrial flutter

Interpretation?

Wolff-parkinson-white syndrome

Interpretation?

Junctional rhythm

Interpretation?

supraventricular tachycardia

Interpretation?

Accelerated junctional rhythm

Interpretation?

Junctional escape beat

Interpretation?

PJC

Interpretation?

Systole

What term describes the repetitive contraction phase of the heart chambers?

Diastole

What term describes the repetitive relaxation phase of the heart chambers?

One cardiac cycle

What does one individual heartbeat correspond to?

Cardiac Output

What term defines the total amount of blood flowing from the heart?

Stroke Volume x HR

What is the mathematical formula for Cardiac Output?

EDV - ESV

What is the mathematical formula for Stroke Volume?

Preload, Afterload, and Contractility

What are the three key determinants of Stroke Volume?

Preload

Which Stroke Volume determinant is defined as Left Ventricular end-diastolic pressure (LVEDP)?

Left Ventricular end-diastolic pressure (LVEDP)

What is the definition of preload?

Afterload

Which Stroke Volume determinant is defined as Systemic vascular resistance (SVR)?

Systemic vascular resistance (SVR)

What is the definition of afterload?

Contractility

Which Stroke Volume determinant is defined as the force of myocardial contraction?

Chronotropy

What electrophysiology term refers to heart rate?

SA Node

What is the primary anatomical site where chronotropic action takes place?

Faster heart rate

What is the effect of sympathetic stimulation on chronotropy?

Slower heart rate

What is the effect of parasympathetic stimulation on chronotropy?

Dromotropy

What electrophysiology term refers to cardiac conduction velocity?

CCS, myocytes, and AV Node

Where do dromotropic effects primarily take place in the heart?

Faster conduction velocity

What is the effect of sympathetic stimulation on dromotropy?

Slower conduction velocity

What is the effect of parasympathetic stimulation on dromotropy?

Ionotropy

What electrophysiology term refers to myocardial contractility?

Ventricles

What anatomical chamber site is primarily affected by ionotropic changes?

Stronger contraction

What is the effect of sympathetic stimulation on ionotropy?

Not significant

What is the parasympathetic effect on ionotropy?

Lusitropy

What electrophysiology term refers to myocardial relaxation rate?

Ventricles

What anatomical chamber site is the primary target for lusitropic action?

Faster relaxation

What is the sympathetic effect on lusitropy?

Not significant

What is the parasympathetic effect on lusitropy?

Positive and negative charges

What must be present for electrical current to flow in the heart?

Electrical stimulus

What type of stimulus do all heart muscles require to fire and pump blood?

Without an outside stimulus

How do cardiac myocytes fire or depolarize under normal physiological conditions?

Polarized

What electrical state must a cell be in first before it can depolarize?

Action potential

What term describes the potential electrical charge created by cell polarization?

Cardiac Conduction Pathway

What specialized myocardial pathway coordinates cardiac depolarization throughout the heart?

Electrolyte abnormalities

What clinical laboratory abnormalities can directly alter cardiac function?

60 to 100 BPM

What is the normal intrinsic pacemaker rate range of the SA Node?

Bradycardia

What clinical term describes a heart rate of less than 60 BPM?

Tachycardia

What clinical term describes a heart rate of greater than 100 BPM?

40 to 60 BPM

What is the intrinsic pacemaker rate range for junctional rhythms?

AV Node and Bundle of His

What anatomical structures give rise to junctional rhythms?

20 to 40 BPM

What is the intrinsic pacemaker rate range for ventricular rhythms?

Distal to the Bundle of His

Where do ventricular rhythms originate anatomically?

Dr. William Einthoven

Which historical pioneer is associated with early ECG electrophysiology work?

Atrial depolarization and ventricular depolarization

What two major electrical depolarization events are evaluated on an ECG tracing?

Bipolar leads

What category of limb leads do leads I, II, and III belong to?

Unipolar leads

What category of limb leads do augmented vector leads (aVR, aVL, aVF) belong to?

Fourth intercostal space to the right of the sternum

What is the exact anatomical placement for ECG lead V1?

Fourth intercostal space to the left of the sternum

What is the exact anatomical placement for ECG lead V2?

Fifth intercostal space at left midclavicular line

What is the exact anatomical placement for ECG lead V4?

Level with lead V5 at left midaxillary line

What is the exact anatomical placement for ECG lead V6

P-Wave

What wave represents depolarization of both atria?

0.08 to 0.11 seconds

What is the normal duration of the P-wave?

SA node

What structure initiates the normal start of the ECG complex?

Biphasic and notched

What are two normal variations that can be seen in a P-wave?

QRS Complex

What ECG wave or complex represents depolarization of both ventricles?

Less than 0.12 seconds

What is the normal duration of the QRS complex?

Ventricular size

What is the overall amplitude (size) of the QRS complex related to?

Pathologic Q wave

A Q wave that is 0.03 seconds or wider or greater than 1/3 of the R wave height represents what?

Supraventricular

Narrow QRS complexes typically originate from what region?

T-Wave

What ECG wave represents ventricular repolarization?

Same direction as QRS complex

In what direction does the normal T-wave deflect relative to the QRS complex?

Asymmetrical

Is the normal T-wave deflection symmetrical or asymmetrical?

J-Point

What term describes the junction point where the QRS complex ends and the ST segment begins?

Phase 0

Which phase of the cardiac action potential corresponds to ventricular depolarization and the QRS complex?

Phase 2

Which phase of the cardiac action potential corresponds to the ST segment plateau?

Phase 3

Which phase of the cardiac action potential corresponds to rapid repolarization and the T wave?

P-R Interval

What ECG interval is measured from the start of atrial depolarization to the start of the QRS complex?

0.04 seconds

What amount of time is represented by one small box on ECG paper?

0.20 seconds

What amount of time is represented by one large box (5 small boxes) on ECG paper?

1 second

How much time is represented by 5 large boxes on ECG paper?

1 mm

What height/amplitude is represented by one small box on ECG paper?

300 divided by number of large boxes

How do you calculate heart rate for a regular rhythm using large boxes?

10

Count the complexes on a 6-second rhythm strip and multiply by what number to determine average rate?

R-to-R interval

Heart rate on an ECG tracing is generally calculated from which specific interval?

Rate, Regularity, P wave, QRS, Grouping/Dropped beats

What are the core fundamental items examined during ECG rhythm analysis?

60 to 100 BPM

What is the normal rate range for Normal Sinus Rhythm (NSR)?

Regular

What is the rhythm regularity in Normal Sinus Rhythm?

1-to-1

What is the normal P-to-QRS ratio in Normal Sinus Rhythm?

Sinus Arrhythmia

Which sinus rhythm features a rate of 60-100 BPM that varies with respiration?

Inhalation

During Sinus Arrhythmia, does heart rate speed up upon inhalation or exhalation?

Increased venous return / decreased intrathoracic pressure

What physiological change during inhalation causes heart rate to speed up in Sinus Arrhythmia?

TP interval

In Sinus Arrhythmia, which specific interval varies with respirations while the PR interval remains identical?

Sinus Bradycardia

What rhythm is characterized by sinus P waves with a rate less than 60 BPM?