Rhythm Disorders Flashcards
Syncope - Classification
Syncope in A&E
- Syncope with low risk features, likely to be reflex or situational, or syncope due to OH, are discharged from A&E
- High risk features, early prompt assessment in A&E observation unit or syncope unit or are hospitalised
- If neither low or high risk features, A&E observation unit or syncope unit preferred to hospitalisastion
- Manage pre-syncope as syncope - prognosis is the same
- Routine bloods and CXR/CTH have low diagnostic yield and impact on prognosis and should only be utilised if specifically indicated
- Cardiac device and syncope –> prompt interrrogation to avoid hospitalisation
*
Syncope - Risk Stratification
Syncopal Event
LOW RISK
* Typical reflex syncope prodrome (nausea, vomiting, warmth, sweating, lightheadedness)
* Associated with prolonged standing in hot / crowded places
* During a meal or post prandial
* Associated with coughing, micturition, defacation
* Associated with head turning or neck pressure
* Standing from sitting / supine position
HIGH RISK - MAJOR
* New onset chest pain, breathlessness, abdominal pain or headache
* Syncope on exertion or when supine
* Sudden onset palpitations immediately followed by syncope
HIGH RISK - MINOR - ONLY HIGH RISK IF ACCOMANIED BY STRUCTURAL HEART DISEASE OR ABNORMAL ECG
* No warning or v short (< 10s) prodrome
* Family history of SCD
* Syncope in sitting position
Past Medical History
LOW RISK
* Long history (years) of recurrent syncope, the same in character as current episode
* Absence of structural heart disease
High Risk
* Severe structural or coronary artery disease (heart failure, low LVEF, previous MI)
Physical Examination
LOW RISK
* Normal examination
HIGH RISK
* Evidence of GI bleeding on PR exam
* HR < 40 unless athletic training
* BP ≤90mmHg
* Undiagnosed systolic murmur
ECG
LOW RISK
* Normal ECG
HIGH RISK MINOR - ONLY IF ASSOCIATED WITH HISTORY CONSISTENT WITH ARRHYTHMIC SYCNOPE
* Pre-excitation
* Paroxysmal AF or SVT
* Mild sinus bradycardia or slow AF (40-50)
* Mobitz 1 second degree AV block or first degree AV block with v prolonged PR
* Atypical Brugada
* Inverted T waves in R precordial leads or Epsilon waves
* Short QTc (≤340ms)
HIGH RISK MAJOR
* Changes consistent with acute ischaemia
* Mobitz 2 2nd degree AV block and 3rd degree AV block]
* Slow AF (< 40)
* Sinus bradycardia (< 40) or sinus pauses >3s in the absence of physical training
* Prolonged QTc (≥460ms)
* BBB or interventricualr conduction delay, LVH, Q waves consistent with ischaemic heart disease or cardiomyopathy
* VT (NSVT or sustatined)
* Type 1 Brugada (coved STE in V1-3)
* Dysfunction of ICD or cardiac device
Sycnope Investigation - Carotid Sinus Sensitivity
- Carotid sinus massage recommended in patients > 40 years, who have symptoms consistent with reflext syncope
- Positive test if bradycardia/asystole, or hypotension that reporduces symptoms
- Positive CSM without syncope -> carotid sinus hypersensitivity. Positive CSM with history of reflex syncope -> carotid sinus syndrome
- Do CSM with cuation in patients with history of TIA / stroke / carotid stenosis >70% due to riskof stroke
Sycnope Investigation - Active Standing
- Intermittent HR and BP measurement when supine then intermittently when standing for 3 mins
- Beat to beat non invasive BP and HR may be preferred when short lived BP changes are suspected such as in initial OH
- Sycope due to OH confirmed when SBP falls by ≥20mmHg, DBP falls by ≥10mmHg or SBP ≤90mmHg with symptoms reproduced. If BP changes and history consistent with OH, syncope from OH considered likely
- POTS likely when HR increases by > 30bpm or to >120 bpm in 10 minutes active standing in the absence of OH that reporduces spontaneous symptoms
Sycnope Investigation - Tilt Testing
- Consider in patients with suspected reflex syncope, OH, POTS, psychogenic pseudosyncope
- Consider to educate patients to recognise symptoms and learn physical manouvres
- Reflex syncope, OH, POTS, PPS likely if symptoms reproduced along with characteristic circulatory patterns
- Tilt table can suggest hypotensive suscpetibility, which can exit in reflex syncope and cardiac syncope - can help guide pacemaker therapy
- Tilt table can help distinguish epilspesy from syncope and syncope from falls
Sycnope Investigation - Autonomic Function Testing
Valsava manouvre
* Consider in patients with suspected nueorgenic OH
* Consider to diagnose hypotensive tendency in some forms of situational syncope
Deep Breathing Test and other autonomic function tests
Consider to assess autonomic function in patients with suspected neurogenic OH
* May consider other autonimic function tests (mental arthimetic, cold water, 30:15 ratio) in suspected neurogenic OH
ABPM
* ABPM recommended to diagnose nocturnal hypertension in patients with autonomic dysfunction
* Consider AMBP to monitor degree of OH and supine hypertension in patients with autnomic dysfunction
* May Consider ABPM or HBPM to detect hypotension during episodes of otherostatic intolerance
Sycnope Investigation - ECG Monitoring
- Immediate in hopsital ECG monitoring indicated in patients at high risk
- Consider Holter monitor in frequent syncope (≥1 / week)
- Consdier external event recorders early after index syncope event in patients with an inter-symptom interval < 4 weeks
- ILR indicated (1a) in patients with recurrent syncope of uncertain origin and high likelihood of recurrence within the battery life of the device
- ILR indicated (1a) in high risk patients in whom work up did not lead to a specific cause who do not have a conventional indication for PPM or ICD
- Consider ILR in suspsected or certain reflex syncope with frequent episodes
- Consider ILR when epilepsy suspected but treatment ineffective
- May consider ILR in unexplained falls
- Arrhythmic syncope confirmed when correlation between arryythmia (tachycardia or bradycardia) and syncope
- Consider arrhthmic syncope when Mobitz 2 second degree, third degree or V pause of >3 s (except in young trained people)
Sycnope Investigation - EP study
- EP study indicated when previous MI or other scarring conditions and syncope remains unexmplained after non-invasive investigation
- Consider in syncope and bifascicular block when no explanation after non-invasive investigation
- Consider in sycope preceeded by brief palpitations when no explanation after non-invasive investigation
- May consider in sinus bradycardia with no symptoms when syncope and bradycardia not clearly related
- PPM indicated in syncope with bifascicular block if either resting H-V interval of >70ms or 2nd or 3rd degree His-Purkinje block during incremental atrial pacing or with pharmacological challenge
- If myocardial scar and inexplained syncope, do VT stim study
- If structural heart disease with syncope precipitated by palpitations, do SVT/VT stimulation study
- Consider PPM in patients with syncope and resting sinus bradycardia with prolonged sinus node recovery time
Sycnope Investigation - Echocardiography
- Indicated when structural heart disease suspected
- Exercise 2D and doppler echo in HCM with suspected inducible LVOTO with resting or provoked LVOT gradeint < 50mmHg
Sycnope Investigation - Exercise Testing
- Recommended for patients with syncope during or after exercise. During exercsie usually cardiac, after exercise, almonst always reflex syncope
- Sycnope due to AV block is confirmed if AV block develops on exercise (even without syncope)
- Reflex syncope diagnosed if syncope comes on immediately after exercise in the presence of severe hypotension
Syncope Treatment - Reflex Syncope
Syncope Treatment - Pacing in Reflex Syncope
Syncope Treatment - Pacing in Reflex Syncope - Decision Tree
Syncope Treatment - Orthostatic Hypotension
Syncope Treatment - Cardiac Arrhythmias
SVT syncope - ablation 1a, medications IIa
VT syncope - ablation 1a, ICD 1a/IIa, medications IIa
Syncope Treatment - LQTS
- Beta-blockers first line, ICD when unexplained syncope on BB
- Left cardiac sympathetic denervation should be considered when can’t tolerate BB, ICD contraindicated or multiple ICD shocks
- ILR instead of ICD if syncope but low risk of SCD on multiparametric analysis
Atrial Fibrillation - Screening
- Opportunistic screening using pulse taking and ECG rhythm strips recommended in patient ≥65 (1b)
- Interrogate PPM and ICD regularly for AHRE
- Consider systematic screening in patients ≥75 or high risk of stroke
- Formally diagnose AF only when 30s of rhythm strip or 12 lead ECG shows AF
Atrial Fibrillation - EHRA Symptom Scale
1- No symptoms
2a - Normal daily activity not affected by symptoms relating to AF
2b - Normal daily activity not affected by symptoms relating to AF, but patient is troubled by symptoms
3 - Normal daily activities are affected by symptoms related to AF
4 - Normal daily activities discontinued
1c - quantify symptoms with EHRA scale before and after initiation of therapy
1c - evaluate symptoms before and after cardioversion to aid rhythm control decisions
Atrial Fibrillation - CHADS-2-VASc Score
Mechanical heart valve or mod/severe MS - VKA
If not
CHADSVASC ≥2 in men and 3 in women - NOAC.
Consider when ≥1 in men and 2 in women
Atrial Fibrillation - HASBLED
Atrial Fibrillation - NOACs - Doses
Dabigatran
* 150mg BD
* Reduced dose 110mg BD
* Criteria for dose reduction:
≥ 80 years
Verapamil use
Increased bleeding risk
Rivaroxaban
* 20mg OD
* Reduced dose 15mg OD
* Criteria for reduced dose
CrCl 15-49ml
Apixaban
* 5mg BD
* Reduced dose 2.5mg BD
* Criteria for reduced dose
2/3 of:
≥80 years old
Weight ≤60kg
Cr ≥1.5mg/dL (>133umol/L)
Edoxaban
* 60mg
* Reduced dose 30mg
* Criteria for reduced dose
CrCl 15-50
Weight ≤60kg
Concurrent use of dronaderone, ciclosporine, ketoconazole, erythromycin
Atrial Fibrillation - Rate Control
Atrial Fibrillation - Rhythm Control
Atrial Fibrillation - Cardioversion
- For pharmacological cardioversion of recent onset AF, IV vernakalant (exlcuding severe heart failure and recent ACS), flecainide or propafenone (excluding patients with severe structural heart disease) recommended (1a)
- IV amiodarone recommended for AF cardioversion in patients with severe heart failure if delayed cardioversion appropriate
- Cardioversion (electrical or pharmacological) is recommended in symptomatic AF as part of a rhythm control strategy
- Pharamcological cardioversion only indicated in haemodynamically stable patients, after consideration of VTE risk
- Consider pre-treatment with amiodarone, propafenone, flecainide or ibutilide to facilitate success of DCCV
- Consider pill in the pocket PO flecainide for patients with no strucutral heart disease and recent onset, infrequent, AF “pill in the pocket”
- AVOID pharmacological cardioversion in patients with sick sinus syndrome, AV conduction disturbance or QT >500ms unless risks of pre-arrhythmia and bradycardia have been considered
Atrial Fibrillation - Rhythm Control Drugs
Flecainide and Propafenone
* Flecainide: 200-300mg PO, 2mg/kg IV over 10 mins for cardioversion
* Propafenone: 450-600mg PO, 1.5-2mg/kg over 10 mins
* AVOID in
Ischaemic heart disease or significant structural heart disease
May induce hypotension and atrial flutter with 1:1 conduction
Flecainide may cause mild QRS widening
Do not use for cardioversion of Flutter
Vernakalant
* 3mg/kg over 10 mins. Wait 10-15 mins after first infusion then 2mg/kg over 10 mins
* AVOID in
Hypotension, NHYA III or IV heart failure, Recent ACS, Severe AS, Prolonged QT
May cause hypotension, QT prolongation, QRS broadening and NSVT
Amiodarone
* 5-7mg/kg over 1 hour then 50mg/kg over 24 hours
* AVOID in
Only if no other option in thyrotoxicosis
May cause phlebititis - use large cannula in large vein
May cause hypotension, bradycardia, AV block, QT prolongation
** Ibutilide**
* 1mg over 10 mins (0.01mg/kg if under 60kg), repeat after 10-15mins
* Effective for Atrial flutter cardioversion
* Should not be used in prolonged QT, severe LVH or low LVEF
* Should be used in CCU setting as may cause long QT and TdP
* ECG monioring for at least 4 hours following
Atrial Fibrillation - management of bleeding on anti-coagulation
Narrow Complex Tachcardia - Differential Diagnosis
Management of a Narrow Complex Tachycardia in the absence of an established diagnosis
Management of a Wide Complex Tachycardia in the absence of an established diagnosis
Atrial Tachycardia - Management (Acute and Chronic)
Macro-re-entrant Atrial Tachycardia - Acute Management
Anticoagulate for MRAT with AF - 1a
Consider anticoagulation for MRAT without AF (IIa)
Macro-re-entrant Atrial Tachycardia - Chronic Management
Ventricular Arrhythmias - Management of incidentally found NSVT
Ventricular Arrhythmias - First Sustained Monomorphic VT Episode
Ventricular Arrhythmias - Management post sudden cardiac death survival
Sudden Death
- Clinical evaluation of first degree relatives
- autopsy - diagnosis made - targetted genetic testing of first degree relatives
Ventricular Arrythmias - Acute Management of Regular, Wide Complex Tachycardia
Ventricular Arrhythmias - ICD discharges / electrical storm
Do not implant ICD in patient with incessant VAs unless VAs controlled
Ventricular Arrhythmias - Polymorphic VA
Ventricular Arrhythmias - Monomorphic VA
Non-selective beta blocker preferred
Ventricular Arrhythmias during STEMI
- IV betablockers indicated for recurrent PVT/VF during STEMI unless contraindicated
- Then add IV amiodarone if ongoing (IIa)
- Then add IV lidocaine (IIb)
- Only BB given prophylactically to prevent arrhythmias, no other AA
- Assess LVEF prior to discharge in all STEMI
- In patients with LVEF ≤40% , reassess in 6-12 weeks ?ICD
ICD decision making after MI
ICD decision making in chronic CAD
Chronic Management of PVCs / Monomorphic VT
If VE burden ≥10%, regular LV function assessment
Catheter ablation first line for PVCs/VT from RVOT of left fascicles (1a)
BB on non-DHP CCBs first line for non RVOT/Left fascicular VT
Management of VE burden ≥10%
Idiopathic VF Management
Long QT Syndrome - diagnostic criteria
Mutations in repolarising K channels
LQT1
- Loss of function mutations in KCNQ1 - major determinant of phase 3 of the action potential
- Critical for AP adaptation in tachycardia
- Also relevant in AR form of LQTs
- Trigger - swimming /exercise
- ECG - broad, peak T wave
LQT2
- Loss of function mutation in KCH2 (hERG) and reduced rapidly activating K current
- Trigger - loud noise/emotional stress
- Biphasic T wave
LQT3
- Gain of function mutation in SCN5A resulting in increased Na activity during plateau at late phase of the action potential
- Trigger - rest
Risk:
LQT2/3 >risk than LQT1
Highest risk: JLN syndrome, Timothy Syndrome, Anderson-Tawil syndrome
QTc> 500 high risk, >600 very high risk
T wave alternans
Early onset life threatening arrhthmia
Long QT Syndrome - management
Rx - Nadolol - if cant get, Propranolol
CPVT - Management
- Ryanodine receptor (RYR2) and calsequestrin gene (CASQ2) mutations
Diagnosis:
- Positive genotype or
- Normal heart, normal ECG, bidirectional or polymorphic VT on exercise
* Normal heart structure, normal ECG, VAs with emotion and exercise
* Avoid exercise and stress
* Non-selective BB (nadolol or propranolol)
* ICD in survivors of CA
Brugada Syndrome
- Diagnosis:
- Spontaneous Type 1 Brugada Pattern (J point elevation with >2mm coved ST elevation and TWI in at least 1 right precordial lead (V1 and V2)) and no other heart disease
- Induced Type 1 Brugada pattern with fever or Na channel blocker and survived VF or PVT cardiac arrest, no other heart disease
Consider diagnosis if:
- Induced Type 1 Brugada pattern and
1) Arrhythmic syncope or nocturnal agonal respiration
2) FHx Brugada
3) FHx Sudden Death with negative autopsy and suspicious circumstances for BrS
May consider diagnosis if:
- Induced type 1 Brugada syndrome only
- May occur spontaneously or only with Na channel blockers or fever. Need to exclude phenocopies
- SCN5A is causative gene - gene testing recommended in probands
- Triggers - fever, cocaine, alcohol, some anaesthetic drugs, selected anti-arrhythmic drugs
- Recommendations
General - Avoid provoking drugs
- Avoid cocaine, cannabis and excessive alcohol
- Treat pyrexia
Risk stratification, SCD prevention
- ICD for BrS who are survivors of SCD or previous sustained VT
- Consider ICD for BrS with previous arrhythmic syncope
- Consider loop recorder in BrS with unexplained syncope
- If qualify for ICD but refuse/contraindication or reccurent shocks - Quinidine
- Electrical storm - isoprotenerol
- Recurrent appropriate shocks - consider VE/RVOT ablation
Relatives of Sudden Arrhythmic Death Syndrome
Athlete ECG interpretation
Pathway ablation guidelines
