Cardiology Part 1: ECG Waves and Atrial Fibrillation

A comprehensive set of vocabulary flashcards covering ECG wave interpretation, management protocols for Atrial Fibrillation, and cardiac pharmacology based on the cardiology lecture notes.

P wave

The ECG wave generated by the SA node, characterized by a duration of $120\,msec$ ($3$ small squares) and a vertical height of less than $2.5\,mm$.

Right Atrial enlargement

An abnormality indicated by a P wave height greater than $2.5\,mm$, often associated with conditions like Tricuspid Stenosis.

PR interval

An ECG segment representing AVN conduction with a duration of $120-200\,msec$ ($3-5$ small squares) and an inverse relationship with heart rate.

q Wave

The ECG wave representing septal activation, with a duration of less than $40\,msec$ and a vertical height of less than $1\,mm$.

qRS Complex

The component of the ECG representing ventricular depolarisation with a duration of $80-100\,msec$ and heights of less than $5\,mm$ in limb leads and less than $10\,mm$ in chest leads.

ST segment

The isoelectric segment of an ECG located between the qRS complex and the T wave.

T Wave

The ECG wave representing ventricular repolarisation.

QT interval

The interval representing both ventricular depolarization and repolarization, measured from the start of Q to the end of T, with a duration of $360-440\,msec$.

Tetany/QT Prolongation

A condition where QT prolongation occurs due to low levels of Calcium and Magnesium.

QTc (Corrected QT)

A value calculated as $\frac{QT}{RR\,interval}$; prolongation of this value triggers Torsades de Pointes (Polymorphic Ventricular Tachycardia).

Atrial Fibrillation (AF)

A cardiac condition identified on ECG by irregular R-R intervals and absent P waves, often resulting in palpitations.

IV Esmolol

A short-acting Beta blocker used for rate control in patients with Atrial Fibrillation.

IV Verapamil/Diltiazem

Medications used for rate control in Atrial Fibrillation patients who have coexistent poorly controlled asthma or symptomatic COPD.

IV digoxin

A medication that utilizes vagus stimulation for rate control in Atrial Fibrillation patients presenting with acute pulmonary edema.

Synchronized DC Shock

The treatment required for recent onset atrial fibrillation in a patient with crashing blood pressure (Cardioversion).

Beta blocker Contraindications

Clinical conditions including Acute Pulmonary Edema ($BNP$ levels elevated), Bradycardia, Bronchial Asthma (poorly controlled), and symptomatic COPD.

RACE mnemonic

A management strategy for long-standing Atrial Fibrillation: Rate control, Anticoagulation, Chemical Cardioversion (e.g., Amiodarone), and Electrical Cardioversion.

CHADS2-VASC score

A score used to decide on anticoagulation, considering Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/TIA, Vascular Disease, and Sex; Age $\geq 75$ and prior Stroke/TIA history each count for $2$ points.

Non-valvular AFib (NVAF) Anticoagulants

Direct-acting Oral Anticoagulants including Factor Xa inhibitors (Apixaban and Rivaroxaban) and Direct Thrombin inhibitors (Dabigatran).

Warfarin

A Vitamin K Antagonist (VKA) used specifically for Valvular Atrial Fibrillation (e.g., Mitral Stenosis).

Amiodarone

A Class III antiarrhythmic used for rhythm control or chemical cardioversion to suppress ectopic electrical foci.

Multifocal Atrial Tachycardia (MAT)

A condition characterized by irregular R-R intervals on ECG where P waves are present.