What is the proper technique for adequate predilation during coronary angioplasty, including antiplatelet and anticoagulant preparation, balloon selection, inflation protocol, and use of adjunctive devices?

Predilation Technique During Coronary Angioplasty

Antiplatelet and Anticoagulant Preparation

All patients should receive aspirin 81-325 mg before PCI if already on daily therapy, or 325 mg non-enteric aspirin if not previously taking it, with continuation indefinitely after the procedure. 1

P2Y12 Inhibitor Loading Strategy

The timing of P2Y12 inhibitor administration depends critically on the clinical presentation:

For STEMI patients undergoing primary PCI:

• Administer P2Y12 inhibitor loading dose as early as possible at first medical contact 1, 2
• Preferred options: ticagrelor 180 mg or clopidogrel 600 mg 1
• Prasugrel 60 mg may be given promptly but no later than 1 hour after PCI once coronary anatomy is defined 2

For NSTE-ACS patients with planned early invasive strategy:

• Clopidogrel 600 mg or ticagrelor 180 mg should be given as early as possible before or at the time of PCI 2
• Prasugrel 60 mg should be given promptly and no later than 1 hour after PCI once anatomy is known 2

For stable CAD/elective PCI:

• Do NOT pretreat with any P2Y12 inhibitor before diagnostic angiography (Class III recommendation) 2
• Administer 600 mg clopidogrel only after coronary anatomy is known and preferably ≥2 hours before PCI 1
• Pretreatment with prasugrel when coronary anatomy is unknown is contraindicated 2

Anticoagulation Protocol

Administer parenteral anticoagulation to all patients in addition to antiplatelet therapy: 1

• Unfractionated heparin (UFH) is the standard option
• Enoxaparin: if last subcutaneous dose was 8-12 hours before PCI, give additional 0.3 mg/kg IV dose 1
• Do NOT "stack" anticoagulants: patients on subcutaneous enoxaparin within 12 hours should not receive additional UFH 1
• Fondaparinux should NOT be used as sole antithrombin agent; add an anticoagulant with anti-IIa activity 1

Discontinue anticoagulation after uncomplicated PCI 3

Balloon Selection for Predilation

Balloon Sizing Principles

Select a balloon diameter that is 0.8-1.0 times the reference vessel diameter to minimize vessel trauma while achieving adequate lesion preparation. This conservative approach reduces the risk of dissection while still allowing effective plaque modification.

For heavily calcified lesions:

• Start with smaller balloon (0.7-0.8:1 balloon-to-artery ratio)
• Use non-compliant balloons for better force transmission to calcified plaque
• Consider cutting balloon angioplasty for ostial lesions or in-stent restenosis to avoid slippage-induced trauma (Class IIb) 1

For soft/fibrotic lesions:

• Standard semi-compliant balloons at 1:1 ratio are typically adequate
• Avoid oversizing to prevent dissection

Balloon Length Selection

Choose balloon length that covers the entire lesion with 2-3 mm margin on each side to ensure complete lesion coverage without excessive vessel trauma.

Inflation Protocol

Initial Inflation Strategy

Begin with low pressure (4-6 atmospheres) for 15-30 seconds to assess vessel compliance and minimize risk of dissection. Observe for:

• Balloon waist disappearance
• Vessel recoil pattern
• Any signs of dissection on fluoroscopy

Pressure Escalation

Gradually increase pressure in 2-atmosphere increments up to nominal pressure (typically 8-12 atmospheres) if:

• Balloon waist persists
• Lesion appears resistant
• No dissection is evident

For calcified lesions, pressures up to 14-20 atmospheres may be required using non-compliant balloons, but monitor closely for perforation risk.

Inflation Duration

Maintain each inflation for 30-60 seconds to allow adequate plaque compression and vessel wall remodeling. Shorter inflations (15-30 seconds) may be used for initial assessment or in high-risk situations.

Avoid prolonged inflations >2 minutes as this increases risk of ischemic complications without additional benefit.

Number of Inflations

Perform 1-3 inflations as needed based on angiographic result:

• Single inflation if adequate result achieved
• Additional inflations if residual stenosis >30% or significant recoil
• Reassess between each inflation to avoid overtreatment

Adjunctive Devices for Lesion Preparation

Cutting Balloon Angioplasty

Cutting balloon might be considered (Class IIb) for:

• In-stent restenosis where conventional balloon may slip 1
• Ostial lesions in side branches to prevent slippage-induced trauma 1

Should NOT be performed routinely during PCI (Class III) 1

Laser Angioplasty

Laser angioplasty might be considered (Class IIb) for:

• Fibrotic lesions that cannot be crossed with conventional balloon 1
• Moderately calcified lesions resistant to balloon dilation 1

Should NOT be used routinely during PCI (Class III) 1

Rotational Atherectomy

While not specifically detailed in the provided evidence, rotational atherectomy is reserved for severely calcified lesions that cannot be adequately prepared with balloon angioplasty alone.

Post-Predilation Assessment

Angiographic Criteria for Adequate Predilation

Acceptable predilation result includes:

• Residual stenosis <30%
• TIMI 3 flow maintained
• No flow-limiting dissection (Type A-B dissections acceptable; Type C-F require management)
• Minimal elastic recoil

If these criteria are not met, consider:

• Additional balloon inflation at higher pressure
• Larger balloon (if initially undersized)
• Adjunctive device (cutting balloon, rotational atherectomy)

Management of Complications

For dissection:

• Type A-B: proceed with stenting
• Type C-F: immediate stent placement to seal dissection
• Consider glycoprotein IIb/IIIa inhibitor if not already administered 1

For slow/no-reflow:

• Intracoronary vasodilators (adenosine, verapamil, nicardipine)
• Avoid further balloon inflations
• Consider hemodynamic support if needed (Class IIb) 1

Critical Pitfalls to Avoid

Never pretreat stable CAD patients with P2Y12 inhibitors before knowing coronary anatomy - this increases bleeding risk without benefit and complicates urgent CABG if needed 2

Never use fondaparinux as sole anticoagulant during PCI - it lacks anti-IIa activity and increases catheter thrombosis risk 1

Never "stack" anticoagulants - particularly avoid UFH in patients who received enoxaparin within 12 hours 1

Never oversize predilation balloons >1.1:1 ratio - this dramatically increases dissection and perforation risk without improving outcomes.

Never perform routine cutting balloon or laser angioplasty - reserve for specific indications only 1

Discontinue anticoagulation after uncomplicated PCI - continued heparin infusion increases bleeding without benefit 3