Tachycardia - Differential Diagnosis Table - Wide vs Narrow, Regular vs Irregular
Regular Rhythm - Narrow Complex Tachycardia:
• ST vs SVT (AVNRT, OAVRT, AFIutter)
• P-waves. Bedside eval of rate and variability
• Tx: Vagal maneuvers, Adenosine/CCBs
Regular Rhythm - Wide Complex Tachycardia:
• HyperK vs VT > SVT+conduction abnormality
• Don't rely on criteria
• Tx: Meds vs. electricity - amio, procainamide, adenosine
Irregular Rhythm - Narrow Complex Tachycardia:
• AFib > AFIutter + variable block >> MAT
• Determine whether AF is cause/effect
• Tx: Underlying cause vs. Rate/Rhythm control
Irregular Rhythm - Wide Complex Tachycardia:
• HyperK vs AF+WPW vs PMVT vs AFib + conduction abnormality
• Beware AV nodal blockers unless certain of AFib + RBBB/LBBB or identical morphology to prior known QRS
• AFib tx vs. Procainamide vs. electricity
#Tachycardia #Differential #Diagnosis #Table #Wide #Narrow #Irregular #causes #cardiology
Tachycardia - Differential Diagnosis and Management - Narrow vs Wide, Regular vs Irregular
Narrow - Regular:
Use P waves. Positive deflection not AVRT/AVNRT. Absent p try adenosine. If see flutter p = AFIutter.
• Sinus Tachy. 220-Age, resp variability.
• SVT. 140-280, very regular.
• Atrial Flutter. 150+/-20, 2:1.
Narrow - Irregular:
Use P waves. If can't see Afib. If see P, either Flutter or MAT. If not Flutter P waves, is MAT.
• AFib.
• AFIutter.
• MAT. 3 types of Ps.
Wide - Regular:
Assume VT until proven otherwise.
• Monomorphic VTach. Each beat identical. Rate > 120, QRS > 120.
• DDx: SVT + Aberrancy, HyperK, NaChBlocker.
Wide - Irregular:
• Polymorphic VTach.
• AFib + BBB. Rate rarely >200.
• AFib + Pre-excitation. Rate can be 300! Variable QRS morphology.
• Hyperkalemia
- Dr. Sarah Foohey @SarahFoohey
#Tachycardia #Differential #Diagnosis #Management #cardiology #wide #narrow #algorithm #irregular
Atrial Fibrillation RVR - Medications
Diltiazem
• Preferred in patients with chronic lung such as Asthma and COPD
Metoprolol
• Particularly useful when A-fib associated with exercise, after acute MI, or with thyrotoxicosis
• Long-term β-blocker improves patient survival (CCB may worsen outcomes), thus starting a β-blocker upon discharge, strongly consider using the agent for rate control also.
Esmolol
• Use if unsure whether patient will tolerate a β-blocker since the duration of action is only 10 minutes
Digoxin
• Consider as initial therapy for patients with LV dysfunction who:
- Do not achieve rate control targets on β-blockers alone
- Cannot tolerate addition of or increased doses of β-blocker due to decompensated CHF
- Would have digoxin added anyway to improve CHF symptoms independent of A-fib
• Consider as initial therapy in patients with severe hypotension
• Consider as 2nd agent in patients in whom IV BB or IV CCB has failed to control their rate
• May take up to 6-8 hours to work
Amiodarone
• Consider for patients with decompensated heart failure or those with accessory pathways
• 2nd-line agent for chronic rate control when beta-blockers and calcium-channel blockers, alone, combined, or when used with digoxin, are ineffective
Magnesium sulfate
• IV MgSO4 appears to have a synergistic effect when combined with other AV nodal blockers resulting in improved rate control.
• Given in conjunction with beta-blockers and calcium-channel blockers.
#Atrial #Fibrillation #AFib #RVR #Medications #management #treatment #comparison #table
Atrial Fibrillation (A-Fib) Summary
Symptoms:
• Palpitations, light-headedness, dizziness, dyspnea, exercise intolerance, chest pain, near-syncope, syncope.
Why?
Cardiac:
• Valvular heart disease
• Structural heart disease
• Decompensated HF
• New ischemia
Noncardiac:
• Pulmonary disease
• Drugs/toxins
• Metabolic
• Endocrinopathies
Most Common Sustained Arrhythmia:
• Irregularly irregular ventricular rhythm
• Absence of P waves
• Irregular wide-complex tachycardia: bundle branch block or WPW
Rate Versus Rhythm Control:
Traditionally: No mortality benefit of restoring sinus rhythm vs rate control
Rhythm-control strategy possibly better:
• Symptom improvement and success with new-onset AF
• Younger patient age
• Prevent irreversible structural and electrical remodeling
Older patients with chronic AF: rate control
• Diltiazem, verapamil, atenolol, metoprolol
• No benefit of strict versus lenient rate control
Younger patients with symptomatic AF: consider rhythm control (chemical/electrical)
• Antiarrhythmic drugs
• Cardioversion
• Ablation therapy
East-AFNET:
• Success with rhythm control with early Afib and pts with cardiovascular risk factors
Atrial Fibrillation - Testing:
• TSH level (< 5% pts with afibb)
• Pulse oximetry
• Echocardiography - Evaluate the size of the right and left atria, the size and function of the right and left ventricles; to detect possible valvular heart disease, left ventricular hypertrophy, pericardial disease; assess peak right ventricular pressure and also identify left atrial thrombus
• Digoxin level (if patient is taking it)
• CBC, serum creatinine, test for DM
Atrial Fibrillation: Cardioversion
1. Hemodynamic instability → cardioversion
2. Elective cardioversion - First episode or PAF
• AF ≥48 hours/unknown duration
• Anticoagulation for 3 weeks before or TEE to exclude thrombus
• Anticoagulation ≥4 weeks after cardioversion
• "Pill-in-the-pocket" for paroxysmal AF
• Flecainide or propafenone with β-blocker or CCB
Anticoagulation:
• Initial heparin not typically needed
• DOACs generally preferred
• Direct thrombin inhibitor (dabigatran)
• Factor Xa inhibitors (rivaroxaban, apixaban, edoxaban)
• Warfarin: therapeutic INR of 2.0 to 3.0
• Absolute warfarin indications
• Moderate or severe mitral stenosis
• Mechanical heart valve
• Left atrial occlusion an option if anticoagulation contraindicated
#Atrial #Fibrillation #AFib #diagnosis #management #cardiology
Palpitations - Differential Diagnosis Framework
What?
• It is an unpleasant awareness or sensation that the heart is pounding, racing, rapid fluttering or flip-flopping in the chest or neck.
Palpitations Diagnosis:
• Focused medical history
• Physical exam
• 12-lead ECG
• Limited laboratory testing
Heart Rate and Rhythm Regularity:
Have the patient tap out their feeling of palpitations
• Rapid and regular rhythms: PSVT or VT
• Rapid and irregular rhythms: Paroxysmal AF, atrial flutter, or atrial tachycardia with variable block
Mimics:
• Esophageal spasm
• Reflux
• Hiatal hernia
• Stomach rumbling
• Intercostal muscle twitching
CARDIAC CAUSES OF PALPITATIONS:
Arrhythmias:
• Atrial fibrillation/flutter
• Bradycardia caused by advanced atrioventricular block or sinus node dysfunction
• Bradycardia-tachycardia syndrome (sick sinus syndrome)
• Multifocal atrial tachycardia
• Premature supraventricular or ventricular contractions
• Sinus tachycardia or arrhythmia
• Supraventricular tachycardia
• Ventricular tachycardia
• Wolff-Parkinson-White syndrome
Nonarrhythmic Cardiac Causes:
• Cardiomyopathy
• Congenital heart disease
• Congestive heart failure
• Mitral valve prolapse
• Pacemaker-mediated tachycardia
• Pericarditis or myocarditis
• Valvular disease (e.g., aortic insufficiency, stenosis)
• Severe mitral regurgitation
• Severe aortic regurgitation
• Congenital heart diseases with significant shunt
• Cardiomegaly
• Heart failure of various etiologies
• Hypertrophic cardiomyopathy
• Mechanical prosthetic valve
NON-CARDIAC CAUSES OF PALPITATIONS:
Medications/Toxins:
• ETOH
• Caffeine
• Energy drinks
• Methamphetamines
• Cocaine
• Tobacco
• Recent withdrawal of β-blockers
• Serotonergic drugs
• Anticholinergics
Systemic:
• Electrolyte imbalance
• Fever
• Hypoglycemia
• Hypovolemia
• Pheochromocytoma
• Pulmonary disease
• Vasovagal syndrome
• Hyperthyroidism
• Anemia
Psychiatric:
• Panic disorder/Anxiety
• Somatization
Arrhythmias:
• SVT will have an abrupt onset and offset
• Sensation of palpitations associated with anxiety may build and relieve more gradually
• Random palpitations: PVC
• Gradual onset & resolution: sinus tachycardia
• Abrupt in onset & termination: SVT or VT
• Terminates with carotid sinus massage or other vagal maneuvers: SVT-AVNRT or AVRT
• Standing up straight after bending over: AVNRT
Red Flag Symptoms:
• Chest pain: Underlying congenital or acquired heart disease
• Lightheadedness/dizziness: Possible severe tachycardia due to decreased brain flow (VT/Vfib/Afib/WPW)
• Loss of consciousness
• Near-syncope, or syncope: Hemodynamically significant arrhythmia?
• Family history of premature SCD
• Structural heart disease
• Severe bradycardia
#Palpitations #Cardiology #Differential #Diagnosis
Intraoperative Tachycardia - Guidelines for Crises in Anaesthesia
Tachycardia in theatre is often due to inadequate depth of anaesthesia / analgesia or alternatively a reflex to hypotension. Tachycardia should not be treated as an isolated variable: remember to tailor treatment to the patient and the situation.
❶ Immediate action: Stop any stimulus, Check pulse, rhythm and blood pressure:
• If no pulse or impending arrest: use Box A.
• If narrow complex AND not hypotensive first increase depth of anaesthesia/analgesia.
❷ Adequate oxygen delivery
• Check fresh gas flow for circuit in use AND check measured FiO2.
• Visual inspection of entire breathing system including valves and connections.
• Rapidly confirm reservoir bag moving OR ventilator bellows moving.
❸ Airway
• Check position of airway device and listen for noise (including larynx and stomach).
• Check capnogram shape compatible with patent airway.
• Confirm airway device is patent (consider passing suction catheter).
❹ Breathing
• Check chest symmetry, rate, breath sounds, SpO2, measured VTexp, ETCO2.
• Feel the airway pressure using reservoir bag and APL valve <3 breaths.
❺ Circulation
• Check rate, rhythm, perfusion, recheck blood pressure, obtain 12-lead ECG if possible.
❻ Consider underlying problems (Box B).
❼ Consider rate control (Box C).
❽ Call for help; consider electrical cardioversion (Box D) if problem not resolving quickly.
❾ Depth: Consider current depth of anaesthesia AND adequacy of analgesia
POTENTIAL UNDERLYING PROBLEMS
• Stimulation with inadequate depth.
• Consider drug error.
• Also consider: central line/wire; hypovolaemia; primary cardiac arrhythmia; myocardial infarction; electrolyte disturbance; local anaesthetic toxicity (→ 3-10); sepsis (→ 3-14); circulatory embolus, gas/fat/amniotic (→ 3-5); anaphylaxis (→ 3-1); malignant hyperthermia crisis (→ 3-8)
By Association of Anaesthetists @ https://twitter.com/AAGBI
Quick Reference Handbook - Guidelines for crises in anaesthesia
#Tachycardia #Anesthesiology #Anesthesia #Intraoperative #Checklist #Diagnosis #Management #Workup
