CCT (CCI) flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

V1 electrode location

V1 is placed in the fourth intercostal space at the right sternal border, helping identify right ventricular and septal electrical activity.

Standard ECG paper speed

At 25 mm per second, one small box equals 0.04 second and one large box equals 0.20 second on standard ECG paper.

ECG calibration standard

A standard calibration of 10 mm per millivolt means a 1 mV signal produces a 10 mm vertical deflection; always verify this before recording.

Lead I inversion cause

Inversion of lead I with switched aVR and aVL and switched leads II and III suggests left arm and right arm electrode reversal.

Orthostatic blood pressure criteria

A fall of at least 20 mm Hg systolic or 10 mm Hg diastolic within three minutes of standing defines orthostatic hypotension.

Proper blood pressure cuff size

The cuff bladder should encircle about 80 percent of the arm circumference and cover roughly 40 percent of arm length for accurate readings.

Heart rate from large boxes

For regular rhythms, divide 300 by the number of large boxes between R waves; for irregular rhythms count QRS complexes in 10 seconds and multiply by 6.

Normal PR interval range

The normal PR interval is 0.12 to 0.20 second, measured from the start of the P wave to the start of the QRS complex.

Left bundle branch block pattern

LBBB shows QRS duration of at least 0.12 second, broad notched R waves in I and V6, and deep QS or rS complexes in V1.

Right bundle branch block pattern

RBBB shows QRS at least 0.12 second with an rSR prime pattern in V1 and a wide slurred S wave in leads I and V6.

Sokolow-Lyon LVH criterion

Left ventricular hypertrophy is suggested when the S wave in V1 plus the R wave in V5 or V6 is 35 mm or greater.

Bazett QT correction formula

Corrected QT equals the measured QT interval divided by the square root of the RR interval in seconds; QTc above 0.44 second is often abnormal.

Inferior STEMI leads

ST elevation in leads II, III, and aVF localizes injury to the inferior wall, often from right coronary artery occlusion.

Atrial fibrillation hallmark

Atrial fibrillation produces an irregularly irregular ventricular rhythm with no distinct P waves and fine or coarse fibrillatory baseline activity.

Atrial flutter rate relationship

Atrial flutter typically has an atrial rate near 300 per minute; with 2:1 conduction the ventricular rate is about 150 per minute.

First-degree AV block

First-degree AV block is a PR interval longer than 0.20 second with every P wave conducted and a constant PR interval.

Mobitz type I AV block

Mobitz type I, or Wenckebach, shows progressive PR prolongation before a dropped QRS, usually from AV nodal conduction delay.

Mobitz type II AV block

Mobitz type II shows intermittent dropped QRS complexes with a constant PR interval in conducted beats and often indicates infranodal disease.

Third-degree AV block

Complete heart block shows no relationship between P waves and QRS complexes, with atrial and ventricular rhythms independent of each other.

Ventricular tachycardia features

Ventricular tachycardia is a wide-complex rhythm faster than 100 per minute, often with AV dissociation, fusion beats, or capture beats.

Holter monitor recording duration

A Holter monitor continuously records the ECG for 24 to 48 hours, usually with three to twelve leads while the patient keeps a symptom diary.

Event monitor purpose

An event monitor records intermittent ECG over weeks to months, activated by symptoms or automatically, to detect infrequent arrhythmias.

Loop recorder function

An implantable loop recorder continuously monitors and stores ECG data for up to several years, useful for unexplained syncope.

Ambulatory diary importance

Patients record symptom times and activities in a diary so the interpreting clinician can correlate symptoms with ECG rhythm changes.

Holter artifact recognition

Artifact from tooth brushing, cable movement, or muscle tremor can mimic arrhythmia; compare leads and check the diary.

Ambulatory monitor skin prep

Clip hair, gently abrade the skin, and clean with alcohol before applying electrodes to reduce impedance and movement artifact.

Bruce protocol first stage

The first Bruce stage is 1.7 mph at a 10 percent grade, with speed and grade increasing every three minutes.

Target heart rate formula

Estimated maximum heart rate is 220 minus age; a diagnostic test commonly targets at least 85 percent of this value.

Positive exercise ST criterion

Horizontal or downsloping ST depression of at least 1 mm at 80 ms after the J point is a positive ischemia criterion.

Exercise test systolic BP drop

A systolic blood pressure fall of more than 10 mm Hg from baseline during exercise is abnormal and suggests severe ischemia or left ventricular dysfunction.

Exercise test contraindications

Acute myocardial infarction, unstable angina, uncontrolled hypertension above 200/110, and severe aortic stenosis are contraindications to exercise stress testing.

Exercise test recovery monitoring

Monitor ECG and blood pressure for at least 6 to 10 minutes after exercise, because ischemia and arrhythmias may appear only during recovery.