Arrhythmia - Cardiology Flashcards
Definition and Classification of Tachyarrhythmia (A+++)
Definition: Heart rate ≥ 100 with or without abnormal rhythm.
Classification
1- According to QRS width:
- Narrow QRS tachycardia (QRS width <120msec)
- Wide QRS tachycardia (QRS width >120msec)
2- According to site of origin:
- Supraventricular
- Junctional
- Ventricular
3- According to regularity
- Regular
- Irregular
Clinical presentation and Management of Tachyarrhythmia (A+++)
A) Presentation:
1- Asymptomatic (silent AF)
2- Acute palpitations with one of the following (Syncope, chest pain, acute HF)
3- Subacute palpitations with one of the following (- Dizziness, light headedness or Presyncope -Easy fatiguability or Shortness of breathing)
B) Management of Emergency case (Acute palpitations):
1- ABCDE approach: To pick up tachycardia and/or hypotension
2- ECG: Diagnose the type of arrhythmia
3- DC shock or medical treatment: According to ECG and hemodynamic status.
C) Management of outpatient clinic case (Subacute palpitations) :
1- History:
a)Determine onset, offset, course, duration and severity of condition.
b) Look for etiology
c) Ask for complications (Cytogenic stroke in case of AF)
2- Examination: (Present with arrhythmia or in between attacks of arrhythmia)
a) General: Search for manifestations of the cause
b) Local: Search for structural heart disease as predisposing factor for arrhythmia
3- Investigations:
a)ECG as one of the following
- 12 lead ECG or ECG strips
- Short term ECG recording : Holter monitoring
- Extended ECG recording : Event recorders, wearable devices or implantable devices
b) Echocardiogram: Record intracardiac electrical activation during arrhythmia
c) Investigations to determine etiology:
- Laboratory tests (Hormonal, electrolytes, blood picture)
- Echo to detect structural heart disease
- To detect myocardial ischemia (Use Exercise ECG, Nuclear cardiology, coronary angiography)
-MRI: Detect myocardial fibrosis. scars, infiltration
-Genetic testing: Detect offending genes in congenital arrhythmias
Treatment of Supraventricular tachycardia (B)
1- Acute treatment
a) Hemodynamically unstable patient: DC shock
b) Hemodynamically stable patient: Aim to abort the tachycardia with one of the following AV node blocking strategies
- Vagal maneuvers (Carotid massage or induced vomiting)
- IV adenosine (Short acting)
- IV non-dhp CCB
- IV betablockers
- Iv digoxin
- IV amiodarone
2-Long term treatment
a) Medications to prevent recurrence
- non-dhp ccbs
- Betablockers
- Amiodarone
b) EP study and catheter ablation to cure patient and stop need for long term anti-arrhythmic drugs.
Treatment of atrial flutter and Atrial fibrillation (AF) (B)
1- Acute treatment;
a) Anticoagulation: IV loading of parenteral anticoagulation
b) If onset of arrhythmia is within 48hrs the risk of thromboembolism will be low unless sinus rhythm restored. Therefore sinus rhythm control is appropriate if :
1-Hemodynamically unstable : DC cardioversion
2-Hemodynamically stable: Cardioversion with antiarrhythmic drugs -No structural heart disease (CLASS IC propafenone - flecainide) -Structural heart disease (Amiodarone)
c) If onset of arrhythmia is more than 48hrs ago the risk of thromboembolism will be high if sinus rhythm is restored (Unless patient is checked with transesophageal echo). Therefore rate control will be appropriate if:
1- No structural heart disease: IV BB or non-dhp ccb
2- Structural heart disease: IV digoxin.
2- Long term treatment:
a)Anticoagulation:
1. If valvular (mitral stenosis) or prosthetic valve: VKA anticoagulation (warfarin) after bridging therapy with parenteral anticoagulation till reaching INR (2-3)
2. If not→ VKA or DOAC (rivaroxaban or apixaban) anticoagulation for one month. Extension of the anticoagulation treatment after one month will depend on the thromboembolic risk profile of the patient
b) Maintenance of sinus rhythm for patients who underwent rhythm control strategy:
1. No structural heart disease: Class IC “Propafenone - flecainide”
2. Structural heart disease: Class III “Amiodarone - Sotalol”
3. EP study and catheter or surgical ablation (maze procedure): Curative.
c) Maintenance of Rate control for patients who underwent rate control strategy:
a. Selective Beta Blockers: oral Bisoprolol- Metoprololnebivolol.
b. If BB contraindicated: oral non-dihydropyridine CCB. “Diltiazem”
c. If associated with heart failure: oral Digoxin
After one month of adequate anticoagulation and rate control for patients with AF presented more than 48 hours, restoring sinus rhythm can be safely done as above in (rhythm control)
Treatment of Ventricular tachycardia (B)
1- Acute management: Restoring sinus rhythm with DC shock regardless hemodynamics status
2- Long term management to prevent recurrence:
a) Beta blockers or class III Antiarrhythmic drugs
b) EP study and catheter ablation.
3- Device (ICD) implantation could be considered to prevent risk of sudden cardiac death
Etiology of Bradyarrhythmia (b)
1- Degenerative (most common).
2- Physiologic (sleep, pain, severe HTN, athletes).
3- Congenital (well tolerated and asymptomatic for long time).
4- Inflammatory (carditis).
5- Infiltrative.
6- Iatrogenic (drugs, surgical).
7- Endocrine.
8- Ischemic heart disease (more serious in anterior wall MI, and more frequent and benign in inferior wall MI).
9- Electrolyte disturbance (renal failure).
Clinical picture of Bradyarrhythmia (B)
1- Clinical history:
a. To determine onset, course, duration and severity of the condition (impact of altered consciousness on the safety of the patient and the community).
b. Look for etiology
2- symptoms:
a. asymptomatic
b. acute palpitation with:(patient seen in ER)
i. syncope
ii. chest pain
iii. acute heart failure
c. subacute palpitation with (patient seen in OPD)
i. Dizziness, light headedness, presyncope.
ii. Easy fatiguability and shortness of breathing.
3- Signs:
a. Vital signs (bradycardia, systolic hypertension, pallor, abnormal neck veins
waves)
b. General examination (manifestation of the cause).
c. Local examination (manifestation of the cause).
Investigations used in Bradyarrhythmia (A++)
1- ECG: ECG can be recorded by one of the following methods:
* Twelve lead ECG or ECG strips.
* Short term ECG recording: Holter Monitoring.
* Extended ECG recording: event recorders, wearable devices or implantable devices.
* EPS (measurement of SA nodal and AV nodal intervals, and stress pacing the conduction system).
2- Investigations to determine etiology.
a. Laboratory tests (hormonal assay, electrolytes, lime titer, drug levels).
b. Echocardiography: to detect any structural heart disease (aortic sclerosis).
c. Detection of myocardial ischemia using
i. Exercise ECG.
ii. Nuclear cardiology (SPECT scan)
iii. Coronary angiography.
d. Detection of myocardial fibrosis, scars, infiltration using cardiac MRI.
e. Genetic testing isolates offending genes in cases of heart block in patients younger than 40 years old.
Classification of Bradyarrhythmia (A++++)
(Anatomical classification)
1) SA nodal
▪ Sinus bradycardia
▪ SA nodal arrest and block.
2) AV nodal
▪ First degree heart block
▪ Second degree heart block
* Mobitz type I (Wenckebach Phenomenon)
* Mobitz type II
* Advanced type 2 heart block (2:1, 3:1, etc.)
▪ Complete heart block (third degree heart block)
3) Bundle branches
▪ Right bundle branch block (RBBB)
▪ Left bundle branch block (LBBB)
Treatment of Bradyarrhythmia (A++)
1- Emergency treatment (unstable patients with severe hypotension or shock, heart failure, chest pain)
a. Circulatory support. (IV-line fluids and circulatory support)
b. Monitoring.
c. Temporary pacing (transcutaneous or transvenous)
2- Removal of the cause, and treatment of the primary condition.
3- Pharmacological treatment:
a. Usually temporary and symptomatic in patients with no temporary pacing.
b. Including: Atropine and atropine derivatives, Isoprenaline, theophylline and corticosteroids (in patients with acute inferior MI).
4- Pacemaker implantation: an electronic device that senses and paces the heart:
a. Single chamber pacemaker (paces and senses the RV)
b. Dual chamber pacemaker (senses and paces right atrium and right ventricle).
c. Intracardiac pacemaker (new)
d. All pacemakers need regular follow up in pacemaker programmer’s clinic.
