Palpitations

ABCs

vitals including SpO₂, continuous monitor, IV access, assess hemodynamic stability
12-lead ECG now, compare with any old ECG
check RBS and temperature
is the pulse fast or slow, regular or irregular, narrow or broad

unstable: cardiovert, do not medicate

hypotension, signs of shock or poor perfusion, acutely altered mental state, ischemic chest discomfort, or acute heart failure / pulmonary edema, attributable to the tachyarrhythmia → synchronized DC cardioversion is the central action, call for help
sedate first whenever it is feasible without delaying the shock, but never delay cardioversion for medication or to wait for full sedation
irregular broad-complex tachycardia → assume pre-excited AF (WPW): see the drug warning below before giving anything
syncope with palpitations → treat as arrhythmic until proven otherwise
if synchronization fails or the rhythm is polymorphic / disorganized → defibrillate (unsynchronized), do not keep attempting to sync a deteriorating patient
hemodynamic collapse or shock persisting after cardioversion / rhythm correction is no longer arrhythmia management alone → Advanced: Cardiogenic Shock, Advanced: Vasopressors & Inotropes if vasoactive support is needed

pre-excited AF / WPW: do not block the AV node

irregular, broad, very fast (often > 200 bpm) → suspect AF conducting down an accessory pathway
avoid adenosine, verapamil, diltiazem, beta-blockers, digoxin and IV amiodarone: they can accelerate conduction down the pathway and precipitate VF
unstable → synchronized DC cardioversion
stable → urgent cardiology / EP discussion before any drug; if pharmacologic conversion is chosen, procainamide or ibutilide are the agents of choice, not the AV-nodal blockers above

red flags

syncope or presyncope, exertional palpitations, chest pain, significant dyspnea, hypotension or relative hypotension, signs/symptoms of heart failure
known structural or ischemic heart disease, known ECG abnormality or conduction disease, ventricular arrhythmia, sustained rapid rhythm
family history of sudden cardiac death or an inherited arrhythmia syndrome; severe electrolyte abnormality

escalation

call now: hemodynamic instability, syncope, chest pain, broad-complex or pre-excited rhythm
urgent cardiology: new AF needing rhythm decisions, SVT not terminating, suspected accessory pathway, any red flag above
persistent unexplained tachycardia despite treating the trigger

HPI

character: fast or skipping, sudden or gradual onset and offset, duration
associated: chest pain, dyspnea, syncope or presyncope, sweating
triggers: fever, pain, bleeding, dehydration, caffeine, alcohol, salbutamol, thyroxine, withdrawal
background: known AF or SVT, ischemic or structural heart disease, thyroid disease, anemia, anxiety
medications: beta-blocker or digoxin recently held or changed, QT-prolonging drugs, anticoagulant (name and last dose)

examination

perfusion: BP, capillary refill, mental state
pulse: rate, regularity, deficit against the monitor
CVS: murmurs, JVP, gallop
respiratory: crackles, effusion
volume and sepsis: dry mucosa, hypotension, fever with a focus
thyroid: goitre, tremor, lid lag

workup

12-lead ECG done at the bedside; capture a rhythm strip during the episode if intermittent; everything else by suspicion
commonly useful: electrolytes and renal function (arrhythmia-relevant, almost always); CBC if anemia or infection suspected; TSH if thyroid disease suspected
if indicated: troponin (ischemia / myocardial injury), BNP and CXR (heart failure), CRP (sepsis), coagulation (before anticoagulation), pregnancy test, toxicology
imaging: echocardiogram for new AF, murmur or heart failure (not usually overnight)
ambulatory monitoring (outpatient): Holter for daily/weekly symptoms, event recorder or patch for infrequent symptoms

treat

stable with a clear trigger: treat the cause, then reassess the rate
- fever → paracetamol 1 g PO/IV q6h; pain → analgesia; hypovolemia → IV fluids
regular narrow complex (SVT): vagal maneuvers, then adenosine 6 mg rapid IV push, then 12 mg if needed, with continuous ECG recording; regular rhythm only, never AF or irregular tachycardia
new AF, rate control: choice depends on BP, ventricular function, and comorbidities
- beta-blocker first-line: bisoprolol 2.5–5 mg PO OD or metoprolol 25–50 mg PO BD (metoprolol 2.5–5 mg IV if urgent)
- diltiazem / verapamil if beta-blocker not tolerated, only if LVEF preserved (> 40%); avoid if LVEF ≤ 40% or decompensated heart failure (non-dihydropyridine CCBs worsen HFrEF)
- digoxin: option when hypotensive or in HFrEF where beta-blockers / CCBs are limited
  - no universal loading dose: reduce for age, renal impairment, low body weight, interacting drugs (e.g. clarithromycin, amiodarone)
  - standard-risk start 0.25–0.5 mg IV/PO, further doses by response and levels; senior input beyond standard risk
- amiodarone is an option in selected patients, particularly HFrEF where beta-blockers/CCBs are limited or contraindicated: dosing and how it fits below
electrolytes: correct K and Mg abnormalities; optimize aggressively if ventricular arrhythmia or long QT
heart failure features: BNP, CXR, IV diuretic if BP allows; respiratory failure or pulmonary edema not settling with rhythm control and diuretic → Advanced: Mechanical Ventilation
suspected PE: risk-assess, CTPA after senior discussion, bedside echo if unstable
regular, monomorphic broad-complex (presumed VT): treat as VT unless confidently proven otherwise; unstable → synchronized cardioversion; stable → amiodarone; full dosing on the tachycardia page
polymorphic or irregular broad-complex: high-risk
- pulseless or deteriorating → unsynchronized defibrillation
- stable polymorphic VT with long QT → magnesium
- pre-excited AF possible → see drug warning above
bradyarrhythmia causing the palpitations (post-extrasystolic pause, sinus pauses): full assessment and treatment on the bradycardia page
hyperthyroidism: beta-blocker for rate/symptom control, thionamide and endocrine input once confirmed
anxiety / physiologic sinus tachycardia: diagnosis of exclusion only

anticoagulation in new AF

this is the stable pathway: anticoagulation timing never delays emergency cardioversion
stroke risk by a validated score; anticoagulate on the risk, not the rhythm, whether or not sinus rhythm is restored
agent: a DOAC is preferred over warfarin, except with a mechanical valve or moderate-to-severe mitral stenosis, where warfarin is required
a bleeding score (HAS-BLED, ORBIT) is used to fix modifiable risks and book closer review, never to withhold anticoagulation

which score, and where the guidelines differ

2024 ESC uses CHA₂DS₂-VA, which drops the sex category: anticoagulate at ≥ 2, consider at 1.
2023 ACC/AHA/ACCP/HRS keeps CHA₂DS₂-VASc but frames the decision on estimated annual stroke risk ≥ 2 % per year rather than on the score alone.
Either way the score is a prompt for a decision, not the decision.

cardioversion: the 48-hour rule has moved

ESC 2024: early cardioversion without prior anticoagulation or TEE only for AF clearly < 24 hours, after thromboembolic events were documented in the 24 to 48 hour band.
ACC/AHA still works to a 48-hour framework with risk stratification.
Ward rule: anticoagulation starts at cardioversion and continues at least 4 weeks, whatever the duration. Beyond 48 hours, or any uncertainty about onset → 3 weeks of anticoagulation or TEE first.
Recent-onset AF often converts once the trigger is treated: rate control plus treating sepsis, pain or hypovolemia is often the whole overnight job.

amiodarone for AF specifically: rate or rhythm, where it fits

the AF regimen: rate or rhythm control in selected patients (typically HFrEF, where beta-blockers and non-dihydropyridine CCBs are limited), usually after discussion; not the VT indication, despite the similar loading + infusion structure.
Overnight, rate control plus treating the trigger is almost always the right ward answer; rhythm strategy is a cardiology decision.
Amiodarone 150 mg IV over 10 min, then 1 mg/min for 6 hr, then 0.5 mg/min for 18 hr.
Not in pre-excited AF: IV amiodarone is potentially harmful there per current guidance; a common, dangerous error.
stable monomorphic VT is its own indication with a similar structure: VT dosing is on the tachycardia page; do not cross-apply doses without checking.

calculator CHA₂DS₂-VASc · MDCalc ↗︎

evidence

source	type
2025 AHA Adult Tachycardia With a Pulse algorithm	international guideline
2023 ACC/AHA/ACCP/HRS atrial fibrillation guideline	international guideline
2024 ESC atrial fibrillation guideline	international guideline

Verify indication, dose, allergies, interactions, renal/hepatic function and local protocols before prescribing.

see also, MOC+ Volume 2: Cardiopulmonary covers the new-arrhythmia workup: SVT, AF, ectopics. browse the library.

go deeper MOC+ Vol 2 · Cardiopulmonary covers this in the full reference. or the complete set.

free the on-call checklist covers the whole shift on one printable page.

reviewed Jul 2026updated Sep 2026file complaint/palpitations