Diltiazem Dosing for Paroxysmal Supraventricular Tachycardia (PSVT)

Initial Management Algorithm

The American Heart Association recommends adenosine as the first-line agent for stable PSVT due to its rapid action and short half-life 1
If adenosine fails or is contraindicated, diltiazem is an excellent second-line option, as recommended by the American College of Cardiology 1, 2

The initial dose of intravenous diltiazem is 0.25 mg/kg (approximately 15-20 mg for an average adult) administered over 2 minutes, as recommended by the American Heart Association 3, 1

The American College of Cardiology recommends avoiding diltiazem in patients with heart failure or impaired ventricular function 1, 2
The American Heart Association advises against using diltiazem in patients with hypotension 4, 5
Diltiazem is contraindicated in patients with pre-excited atrial fibrillation or flutter (WPW syndrome), as stated by the American College of Cardiology 1, 5
The American Heart Association recommends avoiding diltiazem in patients with AV block greater than first degree 5, 6

Hypotension is the most common adverse effect of diltiazem, as reported by the American Heart Association 3
Bradycardia is a potential side effect of diltiazem, as noted by the American College of Cardiology 3
Worsening heart failure in predisposed patients is a potential risk of diltiazem, as warned by the American Heart Association 3, 1

The American College of Cardiology recommends a maximum daily oral dose of 360 mg for long-term oral management after conversion 6
Diltiazem can be given at 120 mg daily (divided or single dose with long-acting formulations) for long-term oral management, as recommended by the American Heart Association 6

Synchronized cardioversion is preferred over medication in hemodynamically unstable patients, as recommended by the American Heart Association 7
Diltiazem works by slowing AV node conduction and increasing AV node refractoriness, as explained by the American College of Cardiology 3
Resuscitation equipment should always be available when administering IV diltiazem, as advised by the American Heart Association 3

For severe bradycardia, consider atropine or temporary pacing if needed, as recommended by the American Heart Association, based on evidence from Circulation 8
The American College of Cardiology suggests that for severe bradycardia, atropine or temporary pacing may be considered, according to guidelines published in Circulation 8