Heart Rhythm Disorders Dr Husain Shabeeh Consultant Cardiologist & Cardiac Electrophysiologist Croydon University Hospital and King s College Hospital
My interests Diagnosis and management of heart rhythm disorders Electrophysiology studies and ablation for AF, SVT, VT Cardiac devices including PPM, ICD, CRT, ILR Syncope
Agenda Atrial fibrillation SVT Atrial flutter Syncope Anything else you would like to discuss
Atrial Fibrillation
William Harvey Circulation of the Blood (1628) It is...evident that the auricles pulsate, contract...and eject the blood into the ventricles. [The auricle] has to help infuse blood into the ventricle so that [the ventricle] may send it on with greater vigour
Lead%V1% Lead%II% Atrial'fibrilla*on' Loss of P waves Atrial activity ( f waves) rate 300-600bpm Irregular ventricular response (unless heart block or VT)
AF who, when and why? Affects 1-2% of population (over 10% in 80+) 2/3 of patients with AF are aged 65-85 Lifetime risk 25% for individuals over 40y (or 1 in 4!) Causes/associations Male gender, age Hypertension, heart failure, valvular heart disease, ischaemic heart disease, thyroid dysfunction, diabetes, alcohol excess Obesity, OSA Acutely: sepsis, surgery, stress, electrolyte loss, binge drinking Other arrhythmias (e.g. WPW) especially in young
AF is harmful because Thromboembolism Anti-coagulants can reduce this risk by 50-70% Haemodynamics Loss of atrial component of filling Irregular ventricular rhythm High ventricular rates (AV nodal drugs can help with this one only)
AF leads to Relative mortality risk 1.5-2.0 5-fold increase in ischaemic stroke 20-30% of all strokes are due to AF cognitive decline / vascular dementia Increased hospitalisation / healthcare costs 1% of total healthcare spending in UK (currently) Symptoms / QoL: palpitations, breathlessness, exercise incapacity, chest pain, syncope Heart failure (cause and/or exacerbator)
AF detection / screening Pulse check ECG ECG monitoring (e.g. Holter) Prolonged ECG monitoring (e.g. patches, implantable recorders) Personal ECG recorders (e.g. AliveCor) Some patients have these!
Anticoagulation ESC guidelines 2016
Net clinical benefit NOACs vs. warfarin Renda et al Am J Med. 2015
Case 1 74 female Asymptomatic Hypertensive Routine visit to GP found to have irregularly irregular pulse ECG confirms AF with ventricular rate 110 What would you do?
Case 1 1. Rate control Aim initial resting HR < 110 2. OAC CHADSVASc = 3 3. Bloods? Echo? Holter? Refer to Cardiology?
ESC guidelines 2016
58 male Breathless for 4 months No PMHx Alcohol 30 units / week Case 2 Examination Pulse irregular Nil else ECG confirms AF, ventricular rate 120 What would you do?
GP started Bisoprolol 2.5mg Patient felt a little better with better heart rate control but still lethargic and breathless Asked patient to reduce alcohol intake (which he did!) Referred to cardiology Case 2 Seen in cardiology clinic Echo: Mild LV dysfunction in AF, mild LA dilatation CHADSVASC = 0 Referred for DCCV, started on apixaban and amiodarone When came for DCCV found to be in SR. Switched to Flecainide, Bisoprolol and Apixaban lethargic and still has 1 hour episodes of PAF every week Referred to electrophysiologist for ablation.
Beyond electric shocks and poisons can we cure AF? ESC guidelines 2016
AF ablation AF ablation in symptomatic AF patients instead of (or after failed/intolerable) drug therapy (note risk of medium-long term AAD) especially in patients with heart failure (ARC-HF, CASTLE-AF trials, etc.) emerging evidence of prognostic benefit of ablation-based rhythm control compared with rate control Particularly effective in paroxysmal and early persistent AF
AF ablation Pulmonary vein isolation (+/- other substrate modification for persistent AF) Success rates PAF: 70% SR at 1y off AAD after 2-3 procedures 80%-90% persistent AF: 40-50% at 1y, 70-80% with 2-3 ablations (reduced success LA size, duration of AF, structural heart disease e.g. HCM) Complication rates <1 in 1000 death <1 in 200 stroke <1 in 100 major bleeding Kuck K et al. N Engl J Med 2016;374:2235-2245.
Isolation of right pulmonary veins
Case 2 3 month follow-up OPA Well with no further episodes after the first few weeks post ablation. All meds stopped at this OPA (flecainide, bisoprolol, apixaban) 12 months follow-up OPA Remains well Discharged
Case 3 67 female Palpitations last 2 hours with SOB PMHx: Hypertensive irregularly irregular pulse at 160 Feels clammy BP 90/60 What would you do?
Case 3 Unwell patient refer to A&E Adverse features are for DCCV: shock, syncope, ischaemia, heart failure
Atrial Fibrillation or Atrial Flutter on 12-lead ECG or 24-Hr Holter IMMEDIATE ACTIONS REQUIRED TESTS ANTI-COAGULATION FOR STROKE PREVENTION Calculate CHADSVASc (if C is unknown, do not wait for Echo) Male: 0 Female: 1 NO OAC OAC OAC CHOICE: Give patient AFA information booklet Preventing AF-Related Stroke: Anticoagulation - Available from www.atrialfibrillation.org.uk Male: >0 Female: >1 refer to CUH anti-coagulation clinic for informed discussion regarding choice of OAC ALL patients should be offered choice of DOAC or warfarin No RATE CONTROL Poor rate control leads to heart failure (tachycardia cardiomyopathy) Heart rate > 90bpm on ECG? Mean heart rate > 90bpm on 24 Hr Holter? Yes RATE CONTROL AGENTS: 1 st Line: Beta blocker 2 nd Line: Diltiazem/ Verapamil 3 rd Line: Digoxin TITRATE ACCORDING TO RESPONSE OR UNTIL HEART RATE <90bpm CONTRAINDICATIONS/CAUTIONS: Beta blockers: Asthma/ Severe PVD Diltiazem/ Verapamil: LVEF <50% GP to request Tests (and why): ECHO: - To assess LVEF- to calculate C of CHADSVASc - To assess for significant heart valve diseasemay affect choice of OAC - To assess atrial size- affects decision of rate vs rhythm control strategy for AF - NOT REQUIRED IF AGE >75YR AND ASYMPTOMATIC 24 HR HOLTER: - To assess rate control - To check if AF is paroxysmal or persistent BLOOD TESTS: - FBC: To exclude anaemia or infection - LFTs: Affects choice of OAC and antiarrhythmic drugs - U&E, Ca 2+, Mg 2+ : Affects choice of OAC and check electrolyte imbalance - TFTs: To exclude hyperthyroidism and affects choice of drugs Aspirin no longer recommended for SP-AF NEXT STEPS: IF YOUR PATIENT IS <75 YEARS OLD OR HAS ANY OF THE FOLLOWING: HOLTER RESULTS: poor rate control (Mean HR >90bpm), paroxysmal AF bradycardia (pauses > 5secs or mean HR<50bpm) ECHO RESULTS: LVEF <50% less-than-severe MR less-than-severe TR less-than-severe LA dilatation NB If severe MR or TR, refer to Valve Clinic Refer to the Community Arrhythmia Clinic SYMPTOMS (despite good AF rate control): palpitations decreased exercise tolerance shortness of breath chest pain dizziness, pre-syncope or syncope DO NOT REFER Age > 75yrs with persistent AF, good rate control and asymptomatic
Other arrhythmias
What are SVTs? AVNRT AVRT Atrial flutter Atrial tachycardia Rare SVT syndromes Rare Accessory pathway Syndromes Permanent Junctional Reciprocating tachycardia (PJRT) Junctional ectopic tachycardia (JET) Narrow complex VT!
Case 3 34 female Fast regular palpitations every few weeks lasting 10 to 30 mins No PMHx Normal physical examination Normal ECG What would you do?
Case 3 Medications? Await symptom-ecg correlation? Had longer episodes and presented to A&E on 2 occasions
SVT (AVNRT) ECG
AVNRT explanation
Treatment Medication -Used when attacks infrequent -Aim is to change the properties of the pathways so SVT can t happen -Drugs that act on the AVN BB, Ca Channel blockers, digoxin -Drugs that change the speed of conduction Flecainide -Don t need OAC - ACUTE vagal manoeuvres adenosine or BB Ablation - For pts who are intolerant of medications or who have break through symptoms - Success / cure rate >95% - Main complication we worry about is PPM
Case 3 Slow pathway ablation for AVNRT All medications stopped the same day as ablation OPC 3/12 no symptoms, discharged
AVRT Due to an extra fibre of electrically conducting tissue in the heart / accessory pathway Pre-excitation / delta wave WPW Concealed accessory pathway
WPW / accessory pathway
Treatment - WPW small risk of preexcited AF and sudden death - Medical Mx Ablation - Only curative strategy - Aim is to find the accessory pathway and ablate it - APs can be on the right side or the left side of the heart (TV or MV) - Success (cure) rates >90-95%
Atrial Flutter Arrhythmia from the right atrium Like AF in that it is fast and patients usually need to be on oral anticoagulation Has a characteristic ECG Heart rate in atrial flutter is usually 150bpm (2:1 AV conduction) pre rate control
Flutter ( F ) waves at 200-300bpm Slow downstroke/rapid upstroke II/III/aVF (typical flutter) Often regular ventricular response (classically 150bpm 2:1 pre-rate control) Lead%V1% Effect&of&adenosine& Lead%II%
Treatment Medical -Anticoagulation (CHADSVASC score) -Ventricular rate control Robust circuit so often doesn t work. AV nodal blockers (BB, CaB) and conduction slowers (Flecainide) -DCCV successful but may not last. Ablation Only curative strategy Success rate >90% Comps 1% Painful so usually done with sedation Target is the Cavotricuspid annulus
Atrial flutter
Case 4 23 female Episodes of light-headedness for last couple of years, but increasing frequency. Often in warm places (e.g. train), always standing. Has had a 6 episodes of LOC last 1 year, including injury to hand, and shorter warning. Quick recovery from LOC No tongue biting / incontinence / shaking No PMHx Normal physical examination Normal ECG Fairly active with work and young child What would you do?
Case 4 History consistent with vaso-vagal syncope Current fluid intake: 2 glasses water 3 cups coffee Cola with lunch Advised: 2.5-3 litres non-caffeinated, non-carbonated fluid Added salt to diet (6-9g / day) Counter-pressure maneuvers Lie down to avoid LOC! Improvement in symptoms but still having symptoms at next OPC as new job requires longer train journey
Case 4 Tilt table test Symptoms reproduced with documented hypotension consistent with vaso-vagal syncope Continued symptoms including LOC despite adhering to good fluid status Midodrine started with good effect Likely to improve over time (natural progression) and can reduce Midodrine once stable
Syncope Current CUH referral system: Refer to A&E Syncope associated with angina or known structural heart disease Syncope with abnormal ECG Refer to community clinic Recurrent dizziness or syncope Manage in primary care Suspected vaso-vagal syndrome responding to conservative measures AND no evidence of structural heart disease
Other? Is there anything else you would like to discuss? Any cases you would like to discuss? Any questions?
Summary AF Screening is vital to reduce risk esp. of stroke OAC Rate +/- rhythm control Atrial flutter Treat similar to AF Catheter ablation very successful SVT Usually non-malignant and manage symptoms Pre-excitation on ECG means potentially dangerous especially if has symptoms Thank you!