Should heparin be administered prior to Digital Subtraction Angiography (DSA) in a patient with a massive infarct?

Heparin Administration Prior to DSA in Massive Infarct

Heparin should NOT be routinely administered prior to DSA in patients with massive infarct, as there is no evidence that early anticoagulation improves outcomes and it significantly increases the risk of hemorrhagic transformation, particularly in large infarcts. 1, 2

Primary Recommendation Based on Stroke Evidence

The decision to withhold routine heparin before DSA in massive infarct is based on several critical considerations:

• Large infarcts carry the highest risk of hemorrhagic transformation, and anticoagulation compounds this risk without proven benefit for mortality or functional outcomes 1, 2

• A comprehensive meta-analysis of over 12,000 patients with acute ischemic stroke found no evidence that patients at higher risk of thrombotic events or lower risk of hemorrhagic events benefited from heparins, and guidelines for routine or selective use should be revised 2

• The American Heart Association guidelines note that hemorrhagic transformation risk after acute ischemic stroke is a major concern, and while early heparin treatment showed some association with functional recovery in smaller strokes, this benefit must be weighed against bleeding risk 1

Procedural Anticoagulation During DSA

If DSA proceeds to endovascular intervention, heparin management differs:

• Administer heparin bolus (60-100 U/kg) only AFTER arterial access is obtained and the decision to proceed with mechanical thrombectomy is made, not before the diagnostic portion 1, 3

• For diagnostic angiography alone without intervention, systemic heparinization is not indicated 1

• During catheter ablation or interventional procedures, heparin is given just before or after access to the arterial bed, with the first dose typically administered after trans-septal puncture or arterial sheath insertion 1

Specific Exceptions Where Heparin May Be Considered

There are limited scenarios where heparin might be used, but these do NOT apply to routine massive infarcts:

• Non-occlusive intraluminal thrombus visible on imaging may benefit from intravenous heparin, with case series showing thrombus resolution without hemorrhagic complications 4, 5

• High-risk cardiac sources including left ventricular thrombus, mechanical heart valves, or left ventricular assist devices may warrant anticoagulation, but timing must be carefully considered given infarct size 4

• Symptomatic large artery stenosis >70% without massive infarction represents a different risk-benefit profile 4

Critical Caveats for Massive Infarcts

Massive infarcts specifically contraindicate early heparin use:

• Patients with CT-visible evidence of recent cerebral ischemia had increased risk of both thrombotic AND hemorrhagic events, eliminating any theoretical benefit from anticoagulation 2

• Neither age, initial stroke severity, blood pressure, nor baseline CT findings predicted hemorrhagic worsening in anticoagulated patients, meaning you cannot safely select patients for heparin based on these factors 1

• The MAST-E study found that patients with symptomatic hemorrhagic transformation were LESS likely to have received heparin, suggesting heparin may have been appropriately withheld in high-risk cases 1

Practical Algorithm for Decision-Making

For diagnostic DSA in massive infarct:

1. Proceed with diagnostic angiography without pre-procedural heparin 2
2. Use continuous low-flow irrigation of sheaths with heparinized saline to prevent catheter thrombosis (standard practice) 1
3. If mechanical thrombectomy is indicated, administer heparin bolus only after the decision to intervene is made 1, 3

If intervention proceeds:

• Give 60-100 U/kg bolus after arterial access 1, 3
• Target ACT 250-350 seconds during the procedure 1
• Discontinue heparin immediately after procedure completion in uncomplicated cases 3

Common Pitfalls to Avoid

• Do not give prophylactic heparin "just in case" intervention is needed - wait until the decision is definitive, as massive infarcts have unacceptable hemorrhagic risk with unnecessary anticoagulation 1, 2

• Do not rely on clinical scoring systems to identify patients who might benefit from heparin in acute stroke - validation studies show these do not reliably predict net benefit 2

• Do not continue heparin post-procedure unless there is angiographically visible arterial dissection or mural thrombus requiring ongoing anticoagulation 3