How to decrease the incidence of no reflow in vein graft PCI?

From the Guidelines

To decrease the incidence of no-reflow in vein graft PCI, use embolic protection devices whenever feasible, as recommended by the 2006 ACC/AHA/SCAI guideline update for percutaneous coronary intervention 1. This approach can capture debris that would otherwise embolize distally, thereby reducing the risk of no-reflow.

• Perform direct stenting when possible to avoid multiple balloon inflations that may dislodge friable material.
• Minimize the number of stents and avoid oversized stents or balloons that could cause graft injury.
• Administer intracoronary vasodilators prophylactically, including adenosine (100-200 mcg bolus), nicardipine (100-200 mcg), or nitroprusside (50-100 mcg) before and after intervention, as suggested by the 2011 ACCF/AHA/SCAI guideline for percutaneous coronary intervention 1.
• Consider glycoprotein IIb/IIIa inhibitors in high-risk cases, as recommended by the 2020 ESC guidelines for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation 1.
• Ensure adequate anticoagulation with heparin to an ACT >250 seconds. If no-reflow occurs despite prevention, administer higher doses of intracoronary vasodilators: adenosine (up to 600-900 mcg), nicardipine (200-500 mcg), or nitroprusside (100-200 mcg), as suggested by the 2008 European Society of Cardiology guidelines for the management of acute myocardial infarction in patients presenting with persistent ST-segment elevation 1. These interventions work by preventing distal embolization of atherothrombotic debris and counteracting microvascular spasm and thrombosis, which are the primary mechanisms of no-reflow in vein graft interventions. The most recent and highest quality study, the 2021 guidelines, although not directly addressing vein graft PCI, provides recommendations for antithrombotic treatment in non-ST-segment elevation acute coronary syndrome patients undergoing PCI, which can be applied to vein graft PCI 1. However, the specific recommendation for using embolic protection devices in vein graft PCI is based on the 2006 ACC/AHA/SCAI guideline update 1, which is the most relevant and highest quality study for this specific context.

From the Research

Decreasing Incidence of No Reflow in Vein Graft PCI

To decrease the incidence of no reflow in vein graft PCI, several strategies can be employed:

• The use of distal embolic protection devices has been shown to decrease the risk of no reflow in saphenous vein graft (SVG) interventions 2.
• Pharmacological management, including the use of vasodilators such as adenosine, nitroprusside, and verapamil, can help improve epicardial flow and microvascular perfusion 3, 4, 5.
• Glycoprotein IIb/IIIa receptor antagonists may also have a role in reducing the occurrence of no reflow during PCI of native coronaries, but their effectiveness in SVG interventions is limited 2, 3.
• Prophylactic injections of intracoronary medications, such as nitroprusside, verapamil, or adenosine, prior to balloon inflation, may be beneficial in preventing no reflow, particularly in vein graft intervention 5.

Treatment of No Reflow

In cases where no reflow occurs, treatment options include:

• Intracoronary administration of medications that induce maximal vasodilatation in small distal coronary vasculature, such as adenosine, nitroprusside, and verapamil 2, 3, 4, 5.
• Mechanical approaches, such as intra-aortic balloon pumping or postconditioning, may also be considered 6.
• A combination of pharmacological and mechanical approaches may be used to treat no reflow, and an algorithm for treatment can be developed based on current literature 6.