PSVT Prescription Templates: Comprehensive Management Scenarios

ACUTE MANAGEMENT TEMPLATES

Template 1: Hemodynamically Stable PSVT - First Episode

For patients WITHOUT structural heart disease or pre-excitation:

Rx: Adenosine 6 mg IV

Administer as rapid IV bolus through proximal/large vein
Follow immediately with saline flush
May repeat with 12 mg IV if no response after 1-2 minutes
Expected success rate: 90-95% for AVNRT/AVRT 1, 2
Warn patient about transient chest discomfort, flushing, dyspnea 3

Alternative if adenosine fails or contraindicated:

Rx: Diltiazem 0.25 mg/kg IV (typically 20 mg)

Administer over 2 minutes
May repeat with 0.35 mg/kg (typically 25 mg) after 15 minutes if needed
Success rate: 64-98% 2, 3

Rx: Verapamil 5-10 mg IV

Administer over 2-3 minutes
Success rate: 64-98% 2, 3

Template 2: Hemodynamically Unstable PSVT

For patients with hypotension, altered mental status, shock, chest pain, or acute heart failure:

Rx: Synchronized Cardioversion

Initial energy: 50-100 Joules
Sedation as appropriate
Success rate: essentially 100% 3
This is mandatory and immediate - do not delay for pharmacotherapy 2, 3

CHRONIC PROPHYLAXIS TEMPLATES

Template 3: First-Line Chronic Management - Beta Blocker Option

For patients WITHOUT structural heart disease, normal LV function:

Rx: Metoprolol Tartrate 25-50 mg PO BID

Start 25 mg BID, titrate to 50 mg BID as tolerated
Maximum: 100 mg BID 1

Rx: Metoprolol Succinate 50-100 mg PO daily

Extended release formulation
Start 50 mg daily, titrate to 100-200 mg daily 1

Rx: Atenolol 25-50 mg PO daily

Start 25 mg daily, titrate to 50-100 mg daily 1

Rx: Propranolol 10-40 mg PO TID-QID

Start 10 mg TID, titrate to 40 mg TID-QID 1

Template 4: First-Line Chronic Management - Calcium Channel Blocker Option

For patients WITHOUT structural heart disease, normal LV function, NO pre-excitation:

Rx: Diltiazem 30-90 mg PO TID-QID

Start 30 mg TID-QID
Titrate to 90 mg TID-QID as needed
Typical maintenance: 240 mg/day 4, 1

Rx: Diltiazem Extended Release 120-360 mg PO daily

Start 120 mg daily
Titrate to 240-360 mg daily 1

Rx: Verapamil 80-120 mg PO TID

Start 80 mg TID
Titrate to 120 mg TID as needed
Typical maintenance: 240 mg/day 4, 1

Rx: Verapamil Extended Release 120-480 mg PO daily

Start 120-180 mg daily
Titrate to 240-480 mg daily 1

Template 5: Second-Line Chronic Management - Class IC Antiarrhythmic

For patients WITHOUT structural heart disease, NO ischemic heart disease, normal LV function:

Rx: Propafenone 150 mg PO TID

CONTRAINDICATED in structural heart disease 4
Reduces recurrence rate to one-fifth of placebo 4
Consider combining with beta-blocker to prevent 1:1 AV conduction if atrial flutter occurs 4
Discontinuation rate: ~19-24% due to adverse effects 4

Rx: Flecainide 50 mg PO BID

Start 50 mg BID for PSVT
May increase by 50 mg BID every 4 days until efficacy achieved 5
Maximum for PSVT: 300 mg/day (150 mg BID) 5
CONTRAINDICATED in structural heart disease or recent MI 4, 5
Superior long-term efficacy vs verapamil: 30% complete suppression vs 13% 4
Must combine with beta-blocker to prevent 1:1 AV conduction 4
Monitor ECG and plasma levels in children 5

Template 6: Third-Line Chronic Management - Class III Antiarrhythmics

For patients who failed first/second-line therapy OR have structural heart disease:

Rx: Sotalol 80 mg PO BID

Start 80 mg BID
Titrate cautiously with QTc monitoring
Monitor QT interval closely for torsades de pointes risk 4, 1

Rx: Dofetilide 500 mcg PO BID

Requires in-hospital initiation with continuous telemetry
50% probability of complete symptom suppression over 6 months 4, 1
Equivalent efficacy to propafenone 150 mg TID 4
Mandatory QTc monitoring - risk of torsades de pointes 4
Dose adjustment required for renal impairment 4

Rx: Amiodarone 200-400 mg PO daily

Loading: 400-600 mg daily for 2-4 weeks
Maintenance: 200-400 mg daily 4, 1
Safe in structural heart disease and LV dysfunction 4, 1
Reserve for refractory cases due to toxicity profile 4
Requires baseline and periodic monitoring: TSH, LFTs, PFTs, ophthalmology 4

Template 7: "Pill-in-the-Pocket" Strategy

For patients with INFREQUENT but prolonged, well-tolerated episodes WITHOUT LV dysfunction, sinus bradycardia, or pre-excitation:

Rx: Diltiazem 120 mg + Propranolol 80 mg PO

Take as single dose at onset of symptoms after failed vagal maneuvers
Superior to placebo and flecainide for conversion 4
Rare complications: hypotension, sinus bradycardia 4
Patient must be instructed to perform vagal maneuvers first 4

Rx: Flecainide 3 mg/kg PO (typically 200-300 mg)

Single dose at symptom onset
Only for patients WITHOUT structural heart disease 4
Evidence mixed - some studies show no benefit vs placebo 4
Requires immediate-release preparation 4

Template 8: Pregnancy-Specific Management

For pregnant patients with PSVT:

Preferred Options (Class IIa, Level C-LD):

Rx: Metoprolol 25-50 mg PO BID 1

Rx: Propranolol 10-40 mg PO TID 1

Rx: Digoxin 0.125-0.25 mg PO daily

Loading: 0.5 mg, then 0.25 mg q6h x 2 doses
Maintenance: 0.125-0.25 mg daily 1

Alternative if above fail:

Rx: Verapamil 80-120 mg PO TID 1

Rx: Flecainide 50-100 mg PO BID (if no structural heart disease) 1

Rx: Sotalol 80 mg PO BID (with QTc monitoring) 1

Template 9: Structural Heart Disease/LV Dysfunction

For patients WITH structural heart disease or reduced ejection fraction:

Rx: Amiodarone 200-400 mg PO daily

Loading: 400-600 mg daily for 2-4 weeks
Maintenance: 200-400 mg daily
Only antiarrhythmic proven safe in structural heart disease 4, 1
Requires comprehensive monitoring protocol 4

Rx: Digoxin 0.125-0.25 mg PO daily

Less effective but safer alternative
Contraindicated if pre-excitation present 1

AVOID: Flecainide, propafenone (absolutely contraindicated) 4, 5

Template 10: Renal Impairment

For patients with CrCl <35 mL/min:

Rx: Flecainide 50 mg PO BID

Start at lower dose due to renal clearance
Increase cautiously, no more frequently than every 4 days
Monitor plasma levels and ECG closely 5
Therapeutic level: 200-500 ng/mL 5

Adjust all renally-cleared medications accordingly 5

CRITICAL SAFETY CONSIDERATIONS

Absolute Contraindications to Specific Agents:

NEVER use Calcium Channel Blockers (diltiazem/verapamil) if: 1, 2, 3

Pre-excitation (WPW) present - can cause ventricular fibrillation
Pre-excited atrial fibrillation suspected
Cannot definitively exclude ventricular tachycardia

NEVER use Flecainide or Propafenone if: 4, 5

Structural heart disease present
Recent myocardial infarction
Ischemic heart disease
LV dysfunction

ALWAYS combine Class IC agents with beta-blockers to prevent 1:1 AV conduction if atrial flutter develops 4

PRE-TREATMENT REQUIREMENTS

Before initiating ANY chronic antiarrhythmic: 1, 2

Obtain 12-lead ECG to rule out pre-excitation (delta waves)
Assess for structural heart disease (echo if indicated)
Document baseline QTc interval
Verify normal renal/hepatic function
Educate patient on vagal maneuvers as first-line acute therapy

For Class III agents (sotalol, dofetilide): 4, 1

Mandatory in-hospital initiation with continuous telemetry
Serial QTc monitoring
Dose adjustment for renal function

For flecainide in children: 5

Direct supervision by pediatric cardiologist required
Plasma trough levels at steady state (after 5 doses)
ECG monitoring with each dose change
Therapeutic level: 200-500 ng/mL (up to 800 ng/mL may be needed)

DEFINITIVE TREATMENT REFERRAL

Rx: Catheter Ablation Referral

First-line definitive therapy for recurrent PSVT 1, 2
Success rate: 94-98.5% 1
Low complication rate: 1% risk of AV block for AVNRT 1
Eliminates need for chronic medication 1
Strongly consider before committing to long-term pharmacotherapy 1, 2

What are the prescription templates for managing and treating Paroxysmal Supraventricular Tachycardia (PSVT)?

Help us tailor your experience