Coronary artery perforation during percutaneous coronary intervention (PCI) has been reported in 0.1 % to 3.0 % of all patients undergoing PCI (1-3)， can be related to guidewire advancement， balloon inflation， rupture， subintimal or high pressure inflation， oversized balloon， or subintimal stent deployment(4) It is a rare but life threatening complication. This complication usually requires urgent surgical intervention and often has a poor or fatal outcome (3-6).

Perforation were categorized by Ellis et al as: Type I， extraluminal crater without extravasation; Type II， epicardial fat or myocardial blush without contrast jet extravasation; Type III， extravasation through frank (>1 mm) perforation; or Type III ‘cavity spilling’ (CS) referring to type III perforation with contrast spilling directly into either left ventricle，coronary sinus or other anatomic circulation chamber (3). 

Another classification proposed by Ajluni et al， perforation were classified angiographically as (1) free perforation，defined as free contrast extravasations into the pericardium (Ellis type III) or (2) contained perforation， defined  as contained extraluminal blush or localized rounded crater of contrast–filled vascular lumen (Ellis type I or II). 

Their data showed that overall outcomes were worse for patients with free perforation (tamponade 20%， CABG 60%， death 20%)than with contained perforations (tamponade 6%， CABG 24%， death 6%) (3).

There are several predictors for perforation， such as the presence of complex lesion morphology (ACC/AHA type B2/C) was more frequent in lesions associated with perforations， chronic total occlusion， bifurcation lesions， and moderate-severe angulations or tortuousity， elderly patients and female. The use of devices intended to remove or ablate tissue and the used of stiff and hydrophilic guide wires were associated with higher perforations rate (1，3，5) .

Emergent echocardiography should be performed at the first sign of perforation， and if clinical evidence of tamponade is apparent， immediate pericardiocentesis should be performed(4). Therapeutic strategy employed to treat coronary perforation is best determined by specific angiographic classification (3). 

A conventional strategy to treat coronary perforation includes prolong perfusion balloon inflation and reverse-heparin anticoagulation with protamin to reach an activated clotting time < 130 s; a platelet transfusion is also administered if GP IIb/IIIa-inhibitors was given， if cardiac tamponade occurs， pericardiocentesis is performed (1，2，3，6).   

When the conventional strategy was not able to seal perforations， there are two eventual non surgical strategies available: distal vessel embolization or sealing of the wall ruptured vessel with Polytetrafluoroethylene (PTFE) covered stent (1).
Distal embolization with gel foam particles， polyvinyl alcohol particles or with coil， or injection of autologous clotted blood through micro catheter is the best technique reserved for distal small vessel ( < 1 mm) perforations not amendable to balloon inflation or covered stent deployment (1，3).

There have been numerous reports describing the use of Polytetrafluoroethylene (PTFE) covered stent to treat coronary perforations which fail to seal despite prolong balloon inflations and reversal anticoagulant (1-4，6) .

The implantation of PTFE-covered stents is easy and rapid to deploy， but， an obvious limitation of this stent is lack of flexibility， which may prevent successful delivery beyond the proximal or mid segment of the coronary artery， especially in calcified， tortous， and several diseased vessel segments (1，2，4，5). 

However， the PTFE covered stent appears to be the best strategy for class III perforations， while conventional approach， combining protamine and prolonged balloon inflation， is appropriate for class II perforations.  

In conclusions， treatment of coronary perforation requires early detection， angiographic classification， immediate occlusion of coronary vessel extravasation and relief hemodynamic compromise， reversal of heparin anticoagulation， platelet transfusionin those treated with abciximab， and the use of PTFE-covered stents. 

References:

1. Colombo A， Stancovic G. Coronary Perforations: Old Screenplay， New Actors. J Invasive Cardiol 2004;16(6):302-303.
2. Briguori C， et al.Emergency Polytetrafluoroethylene-Covered Stent Implantation to Treat Coronary Ruptures.Circulation 2000;102:3028-3031.
3. Rogers JH， Lasala JM. Coronary Artery Dissection and Perforation Complicating Percutaneous Coronary Intervention. J Invasive Cardiol 2004;16(9):493-499.
4. Fejka M， Kahn JK. Diagnosis， Management， and Clinical Outcome of Cardiac Tamponade Complicating Percutaneous Coronary Intervention.Cardiovsc Rev Rep 2003;24(8):416-420.
5. Ellis GS， et al. Increased Coronary Perforation in the New Device Era- Incidence， Classification， Management， and Outcomes. Circulation 1994;90:2725-2730.
6. WitzkeCF， et al. The Changing Pattern of Coronary Perforation During Percutaneous Coronary Intervention in the New Device Era. J Invasive Cardiol 2004;16(6);297-301.

摘要：

冠状动脉穿孔是PCI少见而严重的并发症之一。研究显示冠状动脉穿孔的发生率为0.1%～3.0%。Ellis等将其分为Ι型：腔外溃疡龛，但无对比剂外渗；Ⅱ型：心包或心肌内对比剂显影；Ⅲ型：穿孔直径>1 mm伴对比剂外流或向解剖腔室喷射（cavity spilling）。而Ajluni将其分为开放性穿孔（free perforation）和包裹性穿孔（contained perforation）。穿孔具有多种预测因素CTO病变、分叉病变和老年患者等等。发生穿孔需尽快治疗，如出现心脏压塞，立即进行心包穿刺。但应根据分型来决定具体处理策略：延时球囊扩张、逆转抗血栓治疗、PTFE覆膜支架……