Coronary perforation is one of the most feared complications of PCI, as it can lead to pericardial effusion and tamponade. Because effusions from coronary perforations accumulate rapidly, they often cause hypotension, sometimes necessitating emergency pericardiocentesis (and rarely cardiac surgery). Sometimes perforation may not lead to classic tamponade, but instead create a loculated effusion (especially in prior coronary artery bypass graft surgery patients) , causing compression of cardiac chambers, intramyocardial hematoma , or intracavitary bleeding .
Coronary perforations occur more frequently in complex and chronic total occlusion (CTO) PCIs. Although coronary perforations are common in CTO PCI , most perforations do not have serious consequences, and the risk of tamponade is low, approximately 0.3% . However, the risk is higher with retrograde CTO PCI (approximately 1.3%) . In contrast to PCI of non-CTO vessels, occlusion of a perforated target vessel in CTO PCI usually does not cause myocardial ischemia, allowing for testing sequential strategies, preparing hardware, etc.
Perforation classification, causes, and prevention
Coronary perforations are best classified according to location, as location has important implications regarding management . There are three main perforation locations: (1) large vessel perforation, (2) distal vessel perforation, and (3) collateral vessel perforation, in either a septal or an epicardial collateral ( Figs. 26.1 and 26.2 ) . Most coronary perforations (75% in one series) were large vessel perforations, followed by distal vessel perforation (25%) .
The severity of coronary perforations has traditionally been graded using the Ellis classification ( Fig. 26.3 ) :
Class I: A crater extending outside the lumen only, in the absence of linear staining angiographically suggestive of dissection.
Class II: Pericardial or myocardial blush without a ≥1 mm exit hole.
Class III: Frank streaming of contrast through a ≥1 mm exit hole.
Class III-cavity spilling: Perforation into an anatomic cavity chamber, such as the coronary sinus ( Fig. 26.4 ), the right ventricle, the left ventricle, etc.
The above classification has to be adapted to various scenarios discussed below that were not contemplated at the time the Ellis classification was developed (i.e., perforation of epicardial and septal collateral channels).
General treatment of perforations
Treatments specific to each perforation location are described in the following section. The following general measures are useful for managing coronary perforations ( Fig. 26.5 ) :
Balloon inflation proximal to or at the site of the perforation to stop the bleeding. This should be performed immediately to prevent accelerated accumulation of blood in the pericardial space and cardiac tamponade. The balloon should be same size as the vessel and must be semicompliant and inflated to no more than 8–10 atm to ensure occlusion of antegrade flow, without over stretching the vessel. Balloon inflation should be prolonged, lasting at least 10–15 minutes. In some cases, this may be sufficient to achieve sealing of the perforation (particularly if the perforation is less severe, such as Ellis class I or II).
In large vessel perforations, securing a second arterial access should be strongly considered if the guide catheter used is not 8 French, as additional bulky equipment is likely to be needed. The second access can be used to introduce a second guide catheter (“ping pong technique”) with specific hardware to treat the perforation if needed, while maintaining hemostasis at the site of perforation with an inflated balloon through the first guide catheter. Hemostasis should be confirmed using contrast injection.
Administration of intravenous fluids and vasopressors (and atropine if the patient develops bradycardia due to a vasovagal reaction).
Appropriate timing for performing pericardiocentesis : hemodynamic instability requires immediate pericardiocentesis, yet smaller size pericardial effusions may be best managed conservatively, as the elevated pericardial pressure due to the entrance of blood into the pericardial space may help “tamponade the perforation site” and minimize the risk of further bleeding. Pericardiocentesis can frequently be performed using X-ray guidance due to contrast exit into the pericardial space. Echocardiography remains important for assessing the size of pericardial effusion, guiding pericardiocentesis (if time allows) and evaluating the result of pericardiocentesis. Use of an echocardiographic contrast agent can be useful for detecting ongoing bleeding into the pericardial space .
Cardiac surgery notification : notifying cardiac surgery early may facilitate subsequent treatment, if pericardial bleeding continues despite percutaneous management attempts .
Reversal of anticoagulation should in most cases NOT be performed until after removal of all interventional equipment and complete evacuation of blood from the pericardial space, because reversing the effect of heparin carries the risk of guide and/or target vessel thrombosis, as well as thrombosis of the pericardial blood making it inaccessible to percutaneous drainage. Protamine dose for heparin reversal is 1 mg per 100 units of heparin (maximum dose 50 mg), administered at a rate not to exceed 5 mg per minute. Protamine administration may cause anaphylactic reactions in patients treated with NPH insulin in the past or with a history of fish allergy .
If glycoprotein IIb/IIIa inhibitors or cangrelor were used they should be discontinued if a perforation occurs.
Large vessel perforation
Implantation of oversized stents or high-pressure balloon inflations (especially in heavily calcified vessels ( Fig. 26.6 ) or saphenous vein grafts).
Balloon rupture (when balloon rupture occurs, an angiogram should be obtained immediately after removal of the ruptured balloon to determine whether vessel perforation has occurred).
Guidewire exit from the vessel during lesion crossing attempts, followed by inadvertent advancement of equipment (such as balloons or microcatheters) into the pericardial space. Whereas guidewire perforation alone seldom causes blood extravasation and pericardial effusion (because it creates a very small, self-sealing hole), catheter/balloon advancement over that guidewire enlarges the hole, increasing the risk of blood extravasation. Occasionally the contrast extravasation may not occur until after a stent is placed over the perforated area.
Avoid use of oversized stents and balloons (intravascular imaging can help guide balloon and stent size selection as outlined in Chapter 13: Coronary Intravascular Imaging ).
Avoid very high-pressure balloon inflations.
Always confirm guidewire position within the vessel “architecture” (true lumen or subintimal space) before advancing other equipment.
Inflate a balloon proximal to the perforation to stop the bleeding, as described in section 26.2 General Treatment of Perforations.
If extravasation persists despite prolonged balloon inflations, place a covered stent , such as the Graftmaster Rx ( Section 18.104.22.168 ) or PK Papyrus ( Section 22.214.171.124 ) in the United States; the 5 French guide catheter compatible Begraft covered stent ( Section 126.96.36.199 ) is available outside the United States] ( Table 26.1 ) .
Two stents (sandwich)
6 Fr (7 Fr for 4.5 and 4.8 mm stents)
5 Fr (6 Fr for 4.5 and 5.0 mm stents)
Available diameters (mm)
2.8, 3.5, 4.0,4.5, 4.8
2.5, 3.0, 3.5, 4.0,4.5, 5.0
Available lengths (mm)
16, 19, 26
15, 20, 26
Depending on the size of the guide catheter being used and the size of the covered stent, delivery of the covered stent could be achieved using (1) a single guide catheter (also called ” block and deliver ” technique ) ( Fig. 26.7 ) or (2) two guide catheters (dual guide catheter, also called “ping pong” guide catheter, or “dueling” guide catheter technique) ( Figs. 26.8 and 26.9 ) . The goals of both techniques is to minimize bleeding into the pericardium while preparing for covered stent delivery and deployment. If the balloon used for hemostasis and the covered stent can fit through a single (usually 8 Fr for Graftmaster covered stents) guide catheter, then the single guide catheter technique is used, otherwise two guide catheters are required. Covered stents are generally bulky and require excellent guide catheter support and possibly other maneuvers such as distal anchor balloon for delivery. After deployment, a covered stent should be postdilated aggressively to achieve good expansion and reduce the long-term risk of thrombosis. If there are residual dissections beside the covered stents they should be sealed by additional stenting, as a residual dissection can be a reentry point for bleeding.