Distal mechanical protection in percutaneous coronary interventions

The occurrence of fatal events after percutaneous coronary interventions associated with distal embolization of plaque contents has led to the development of new protection strategies. Firstly, pharmacological methods were attempted to deal with the emboli and accompanying myocardial ischemia. Among them, glycoprotein IIb-IIIa receptor antagonists were shown to be beneficial especially during primary percutaneous coronary interventions in patients with acute myocardial infarction. However, as far as the prevention of distal embolization was concerned, these medications were found not to offer a desirable efficacy especially in interventions for lesions with a heavy thrombus load, and in those involving degenerated saphenous vein grafts and carotid lesions. Today, several types of distal mechanical protection devices have been developed to prevent and/or treat distal embolization. They are classified under two headings, namely those having a filter system and a balloon system. The merits and demerits of these devices are reviewed in the light of the literature.