Submodule
Atrial Rhythm Classification
Atrial fibrillation, flutter, focal atrial tachycardia, MAT, AVNRT, and AVRT differ in atrial organization, circuit, AV nodal dependence, and ventricular response.
- Clinical AF confirmation
- Atrial flutter
- Focal atrial tachycardia
- Multifocal atrial tachycardia
Irregular ventricular response
Organized atrial activity
Atrial morphology localizes origin
Abrupt regular tachycardia
Confirm AF on a tracing
Clinical AF diagnosis requires clinician-confirmed electrocardiographic evidence. Disorganized atrial activity and an irregular ventricular response support the diagnosis when AV conduction is not fixed or paced. Wearable alerts can trigger evaluation but artifact and ectopy remain possible.
Separate flutter from fibrillation
Typical flutter is organized macroreentry, commonly around the tricuspid annulus. AV conduction ratio determines the ventricular rate, and 2-to-1 conduction can conceal flutter waves. Flutter shares stroke and cardiomyopathy concerns with AF but has a highly effective circuit-specific ablation option.
Localize focal atrial tachycardia
A discrete atrial focus creates P-wave morphology different from sinus rhythm. Automatic foci can show warm-up and cool-down, while microreentry can begin abruptly. Persistent focal tachycardia can cause ventricular dysfunction and may be treated with ablation.
Recognize MAT as a systemic signal
MAT has an irregular ventricular rhythm, at least three P-wave morphologies, variable PR intervals, and an isoelectric baseline. It commonly accompanies pulmonary disease, hypoxia, electrolyte depletion, or stimulant exposure. Treating the driver is central.
Quick check
Submodule
Atrial Fibrillation Foundations
AF is a progressive atrial disease shaped by burden, remodeling, symptoms, cardiovascular risk, sleep, alcohol, weight, blood pressure, and heart failure.
- AF stages
- Burden and monitoring
- Risk-factor modification
- AF-mediated cardiomyopathy
Describe current disease
Reduce progression drivers
Select anticoagulation
Use shared goals
Use stage to describe current disease
AF staging spans at-risk and pre-AF states through paroxysmal, persistent, long-standing persistent, post-ablation, and permanent AF. Permanent means a shared decision not to pursue rhythm control, not that conversion is physiologically impossible.
Measure burden for the question
Symptoms alone do not quantify AF. Choose ECG, patch, wearable, loop recorder, or implanted-device data based on episode frequency, symptom correlation, post-ablation surveillance, cryptogenic stroke, and whether the result will change care.
Modify the atrial substrate
Weight loss when appropriate, exercise, blood-pressure control, tobacco cessation, minimizing alcohol, and sleep-disordered-breathing evaluation reduce drivers of AF onset and progression. These are part of rhythm care, not optional lifestyle decoration.
Look for AF-mediated ventricular dysfunction
Rapid, irregular, or high-burden AF can cause or worsen cardiomyopathy. Control the rhythm, treat heart failure, exclude competing causes, and repeat ventricular imaging because recovery can establish a reversible arrhythmia-mediated component.
Quick check
Submodule
Rate and Rhythm Control
Stability, symptoms, ventricular function, disease stage, preexcitation, structural disease, and medication risk determine the acute and long-term control strategy.
- Unstable cardioversion
- Rate-control selection
- Rhythm drugs
- Cardioversion and recurrence planning
Do not delay for taxonomy
Match to ventricular function
Protect against embolism
Reassess burden and goals
Cardiovert instability
AF or flutter with rapid ventricular response that causes hypotension, shock, ischemic discomfort, acute heart failure, or altered mental status requires immediate synchronized cardioversion. Stabilization is not delayed for elective anticoagulation steps, although embolic mitigation continues as feasible.
Match rate control to ventricular function
Beta blockers and nondihydropyridine calcium-channel blockers can slow stable AF without preexcitation. Diltiazem and verapamil can worsen decompensated systolic heart failure. Digoxin has slower onset and less exertional control. Amiodarone is reserved for selected contexts because conversion and toxicity remain possible.
Select rhythm drugs by substrate
Class IC agents require absence of important ischemic or structural disease. Sotalol and dofetilide require QT, kidney, electrolyte, and monitored-initiation reasoning. Amiodarone has broad efficacy but major thyroid, pulmonary, hepatic, ocular, neurologic, skin, interaction, and long-term toxicity burdens.
Plan beyond conversion
Electrical or pharmacologic conversion requires rhythm-duration and anticoagulation planning, electrolyte correction, sedation when electrical, monitoring after conversion, and a recurrence strategy. A successful shock does not erase atrial stunning or long-term stroke risk.
Quick check
Submodule
Stroke Prevention
AF thromboembolic prevention follows validated annual-risk estimation, valve context, organ function, interactions, adherence, bleeding modifiers, and longitudinal reassessment.
- Risk scoring and modifiers
- DOAC versus warfarin
- Bleeding-risk mitigation
- Left atrial appendage occlusion
Use modifiers when intermediate
Respect valve exclusions
Avoid aspirin substitution
Update at transitions
Estimate risk and revisit it
Validated risk scores estimate annual thromboembolic risk. At intermediate risk, AF burden, kidney disease, atrial size, hypertrophic cardiomyopathy, obesity, and blood-pressure control can refine decisions. Age and comorbidities change, so the assessment must be repeated.
Choose the eligible anticoagulant
DOACs are preferred for many eligible patients. Mechanical prosthetic valves and moderate or severe rheumatic mitral stenosis require a vitamin K antagonist pathway. Every DOAC dose remains product and indication specific. Aspirin does not provide equivalent cardioembolic protection.
Reduce bleeding without abandoning stroke prevention
Control blood pressure, avoid unnecessary antiplatelets and NSAIDs, address alcohol, anemia, renal and hepatic dysfunction, falls, adherence, and follow-up. A bleeding-risk score should identify modifiable hazards, not act as the sole reason to deny indicated anticoagulation.
Use appendage occlusion selectively
Percutaneous left atrial appendage occlusion can be reasonable in selected patients with sufficient stroke risk and a nonreversible contraindication or high risk on long-term anticoagulation. Procedure risk and peri-device antithrombotic therapy require specialist shared decision-making.
Quick check
Submodule
Regular Supraventricular Tachycardias
AVNRT and orthodromic AVRT depend on AV nodal conduction, while flutter and focal atrial tachycardia may only be exposed, not terminated, by transient AV block.
- Modified Valsalva
- Adenosine
- AVNRT
- Orthodromic AVRT
AV node is in circuit
Check for preexcitation
AV block can unmask waves
Treat source and substrate
Start with stability and vagal maneuvers
Unstable regular narrow tachycardia requires synchronized cardioversion. In stable AV-node-dependent tachycardia, a modified Valsalva can increase termination success. Screen before carotid massage and avoid unsafe or ineffective improvised techniques.
Administer adenosine correctly
Adenosine has an extremely short half-life and requires rapid IV administration with immediate flush under monitoring. It terminates AVNRT or orthodromic AVRT by transient AV nodal block. It can reveal flutter or atrial tachycardia without terminating the atrial circuit.
Recognize AVNRT
Typical AVNRT uses slow and fast pathways near the AV node. Retrograde atrial activation can be hidden within or immediately after QRS. Recurrent symptomatic episodes should include a discussion of catheter ablation, which can be definitive.
Recognize concealed accessory pathways
Orthodromic AVRT usually conducts down the AV node and returns through an accessory pathway, producing narrow QRS tachycardia. A pathway that conducts only retrogradely may have no resting delta wave, so a normal sinus ECG does not exclude AVRT.
Quick check
Submodule
Special Safety and Longitudinal Care
Preexcitation, heart failure, acute coronary syndrome, surgery, pregnancy, pulmonary disease, toxicity, and ablation change familiar atrial-rhythm pathways.
- Preexcited AF
- AF in heart failure
- Acute-illness atrial arrhythmia
- Ablation and postprocedure care
Protect against VF
Avoid harmful negative inotropy
Separate cause from response
Plan before and after
Protect the preexcited ventricle
Preexcited AF can conduct extremely rapidly through an accessory pathway and deteriorate to VF. Cardiovert instability. In stable patients, use an accessory-pathway-safe specialist strategy. Avoid beta blockers, diltiazem, verapamil, digoxin, and IV amiodarone because AV nodal block can favor pathway conduction.
Use ventricular function to shape care
AF can cause or worsen heart failure, and heart failure can sustain AF. Avoid harmful acute negative inotropy in decompensated systolic disease. Rhythm control, including ablation, can improve symptoms and ventricular function in selected patients.
Treat the acute driver
Postoperative stress, infection, hypoxia, pulmonary embolism, ischemia, thyroid disease, alcohol, stimulants, and electrolyte abnormalities can provoke atrial arrhythmia. Stabilize the rhythm when needed while treating the driver and planning follow-up because recurrence can reveal underlying substrate.
Continue risk care after ablation
Ablation can reduce symptoms and AF burden, but recurrence can be silent. Continue monitoring, risk-factor modification, and early postprocedure anticoagulation. Long-term anticoagulation follows stroke risk and current guidance rather than perceived rhythm success alone.
Quick check
Module test
Check the connections.
Each attempt draws 10 questions from the complete 104 question bank.
Each attempt draws a fresh set and rearranges the answer choices.
References
Current clinical foundation.
Lecture material was synthesized with the following contemporary guidance. Verify local policy and current guidance before applying clinical information.