Palpitations and ectopy

Palpitations

• Differential
  • • Arrhythmias – AF/flutter, AVNRT, AVRT, ectopics, sick sinus syndrome, heart block, ventricular arrhythmias, PPM/ICD anomalies
    • Drugs
      • • Caffeine, nicotine, recreational drugs and ETOH
        • For respiratory disease – salbutamol, ipratropium, theophylline, nasal pseudoephedrine
        • For CV disease – hydralazine, digoxin, flecainide, betablocker withdrawal
        • Any drugs that prolong the QTC including some antibiotics, antipsychotics and antidepressants
        • Steroids
    • Structural heart disease – valvular HD, congenital HD, HCM, HF, RV strain from PE
    • Endocrine – thyrotoxicosis, hypoglycaemia
    • Infection/fever
    • Anaemia and dehydration
    • Postural hypotension, vasovagal episodes and POTS
    • Menopause and pregnancy
    • Anxiety / depression / stress / panic attacks
    • Rarer causes – pheochromocytoma, carcinoid, Pagets
• Often difficult to find a cause. Up to 30% diagnosed initially with anxiety, and half of these will get a different diagnosis 3 years later
• Ask about
  • • Triggers – ETOH, drugs (incl over the counter and recreational), situations, stress
    • Frequency / duration / onset
      • • Sudden onset more likely SVT, gradual more likely atrial tachycardia.
        • Ask about the feeling of missed beats
    • Red flags – exercise-associated, syncope, chest pain, SOB, family hx of SCD (in such cases discuss with cardiology)
    • Symptoms of associated conditions eg thyrotoxicosis, OSA, infection, GI bleeding
• Clues to diagnosis
  • • If fear and bradycardia – very often an underlying cardiac cause
    • AVRT becomes less common with increasing age. AF and AVNRT become more common
    • Wearable tech – eg watches with ECG function can be useful
    • Atrial tachycardia is suggested by grouped fast beats, loss of diurnal variation in heart rate, abnormal p wave axis/inverted Ps, feeling of missed beats
• ECG. Assess for
  • • PR interval (WPW, heart block)
    • Atrial or ventricular arrhythmias
    • Ectopics
    • QTC duration
    • Evidence of old/current ischaemia, or ventricular hypertrophy
• Driving
  • • If an arrhythmia has caused incapacity (syncope or pre-syncope) – patient must not drive and should usually inform the DVLA (especially if symptoms remain uncontrolled)
    • Can restart after one month if cause identified and symptoms controlled
    • More rules apply if patient has an ICD or class 2 license
• Investigations to consider
  • • Bloods incl CRP, TFTs, Hb, HbA1c, d-dimer, bone profile, magnesium
    • Prospective event monitoring
    • Wearable devices
    • Holter (not particularly useful if symptoms infrequent. Can be useful if ectopics on ECG to establish burden)
    • Echo if murmur, suspcted structural HD or HF, >10% burden of ventricular ectopics
    • See Cardiological investigations

---

Ectopy

• Atrial ectopics (PACs).
  • • >500 PACs (atrial ectopics) in 24 hours = high burden
    • PACs are not benign (high burden have 2 x stroke risk without AF) and increases risk of later developing AF (due to a type of atrial cardiomyopathy)
    • Probability of AF: if >100 PACs, <9% risk, if >1500 PACs 40% risk
    • Do CHA2DS2-VASc score (imagine if they did develop AF) in order to decide what to do / how to manage risk factors / follow up
    • Can treat with betablockers – bisoprolol, propranolol, nebivolol (or just reassure, depending on how symptomatic)
• Ventricular ectopics (VEs / PVCs)
  • • Early and often wide QRS without preceding Q wave
    • Can be asymptomatic, or cause chest discomfort, skipped beat sensation, SOB, fatigue, pre-syncope. Can be symptomatic at any burden
    • Usually benign unless family hx of SCD
    • Common – at least 1 PVC occurs in 70% of people in 24 hours
    • Origin
      • • Can originate in areas of myocardial fibrosis (although this isn’t particularly important, more important to know if heart is structurally normal or not).
        • Multifocal PVCs or those with non-outflow tract origins, are perhaps more concerning though
        • RV outflow tract PVCs are often amenable to ablation (but can also be a an early manifestation of ARVC)
        • RVOT PVCs tend to be positive in the inferior leads and I, with LBBB morphology.
        • LV originating PVCs are riskier to treat with ablation
    • Complications / associations
      • • PVC-induced cardiomyopathy (most cases occur when burden is >10%, and higher risk when burden >20%). Can be hard to tell if PVC is a symptom or cause of LV dysfunction (consider time course and CMR findings)
        • PVC-triggered malignant ventricular arrythmias (rare)
        • increased incidence of AF and heart failure with PVC rates burden > 0.8%
    • Assess for
      • • Family hx of SCD, cardiac devices, cardiomyopathy
        • Severity of symptoms if present
        • Hx of syncope
        • Impaired LV on last echo (more likely to treat in this instance). Get up to date echo for everyone
    • CMR for some (and always for those with PVC burdens >10% with reduced LVEF not explained by underlying heart disease, or anyone with burden >20%, or if suspicion of cardiomyopathy)
    • Burden
      • • A few are normal (probably ok if <5%). Might discuss with cardio if 5-10% in a young patient. Usually can discharge if burden <10% and no symptoms.
        • >10% is significant. This increases risk of LV dysfunction. So discuss with cardio.
        • >20% is associated with developing a cardiomyopathy / HF. Needs regular echo and most get suppression therapy regardless of symptoms
        • No clear consensus on normal burden but >500 in 24 hours is not normal
        • Non-sustained VT is 3 or more consecutive beats at a rate of >100 with duration of <30s. Non-sustained VT can be normal, but do an echo. Discuss NSVT with cardio unless there’s an obvious cause and plan in place (eg previous MI)
    • Treatment
      • • Reassurance if low symptom burden, normal EF and low burden
        • Pursue PVC suppression if bothersome symptoms or low EF – betablockers 1^st Sometimes then repeat holter to assess impact on burden
        • Can sometimes use CCBs, sotalol, amioderone or flecainide
        • Ablation can be done – usually for RV outflow tract ectopy (ie LBBB / negative morphology of ectopic beats in chest leads and positive beats in inferior leads). 2-5% complication rate (vascular access issues, tamponade, AV block, stroke). Success rate around 85%.
        • Serveillance echo for anyone with burden >10% and no LV dysfunction.