As a result of significant technologic improvements over the past 30 years, percutaneous coronary intervention (PCI) has become an increasingly safe and effective procedure. Along with this maturation, the indications for emergency cardiac surgery for failed PCI have been reduced. Nevertheless, some type of surgical backup strategy continues to be a standard of practice for the optimal performance of PCI. To understand this evolution, it is appropriate to start this chapter with an historical perspective.
On September 16, 1977, Andreas Gruentzig performed the first percutaneous transluminal coronary angioplasty (PTCA) in Zurich, Switzerland. Elaborate precautions were taken in the event that emergency coronary bypass surgery was necessary to rescue an unstable patient following a failed PTCA attempt. These provisions included a roller pump coronary perfusion device, an open ready operating room, and the physical presence of a cardiac surgeon and an anesthesiologist in the catheterization laboratory room.1 Fortunately, the procedure was successful, and the rest is history. Ironically, the birth of angioplasty would not have been possible without the support and interaction of cardiovascular surgeons with cardiologists. Gruentzig freely credited Ake Senning and Marko Turina, his cardiovascular surgeons in Zurich, with allowing him to develop the PTCA technique.
Of Gruentzig’s first 50 patients, 7 (14%) needed emergency bypass operations, but surgery was accomplished with no major mortality or morbidity.2 In June 1979, a PTCA workshop was convened in Bethesda, Maryland, sponsored by the National Institutes of Health National Heart, Lung, and Blood Institute (NIH-NHLBI), at which the initial clinical experience in the technique was discussed. Out of this pivotal meeting, the founding fathers of PTCA took the unprecedented step to commit a fledging procedure and themselves to a comprehensive multicenter registry that would fairly assess safety and efficacy. As a result, the NIH-NHLBI PTCA Registry3 was formed, setting the standards for the rigorous analysis of PCI that continues to this day in various registries, institutional databases, and multicenter randomized trials. It is with this tradition of open granularity that the evolution of PCI and the role of emergency surgery can be best assessed.
Different degrees and complexity of coronary artery bypass graft (CABG) surgery may be necessary following a failed PCI. The most appropriate definitions of urgency are provided by the National Cardiovascular Data Registry (NCDR) CathPCI Registry version 4.4 data elements.4
Elective: The patient’s cardiac function has been stable in the days prior to the operation. Cardiac surgery could be deferred without risk of compromised cardiac outcome.
Urgent: Procedure required during same hospitalization in order to minimize chance of further clinical deterioration. Examples include, but are not limited to, worsening sudden chest pain, congestive heart failure, acute myocardial infarction, anatomy, intra-aortic balloon pump (IABP), unstable angina with intravenous nitroglycerin, or rest angina.
Emergency: Patients requiring emergency operation will have ongoing refractory (difficulty, complicated, and unmanageable) unrelenting cardiac compromise, with or without hemodynamic instability, and be not responsive to any form of therapy except cardiac surgery. An emergency operation is one in which there should be no delay in providing operative intervention. The patient’s clinical status includes any of the following:
Ischemic dysfunction (any of the following):
Ongoing ischemia including rest angina despite maximal medical therapy (medical or IABP)
Acute evolving myocardial infarction with 24 hours before surgery
Pulmonary edema requiring intubation
Mechanical dysfunction (either of the following):
Shock with circulatory support
Shock without circulatory support
Salvage: The patient is undergoing cardiopulmonary resuscitation (CPR) in route to the operating room or prior to anesthesia induction.
This chapter will focus on the above-listed definitions of “emergency” and “salvage” surgery for failed PCI. Complications and emergency surgery for failed structural heart interventions, including transcatheter aortic valve replacement (TAVR), will be covered by the chapters on these various procedures in this textbook.
The coronary indications for emergency CABG surgery for failed PCI include left main dissection, abrupt occlusion, extensive coronary dissection, perforation, cardiac tamponade, retained equipment fragments, and inability to stabilize the affected vessel.
Urgent systemic problems to be corrected may include hypoxia, hypotension, acute pulmonary edema, ongoing cardiopulmonary resuscitation, cardiogenic shock, and uncontrolled bleeding.
Noncoronary indications may also necessitate emergency cardiac and vascular surgery. These include aortic dissection and severe peripheral vascular access complications.
Clarification of the actual logistics and role of the surgeon and the operating room facilities is necessary to avoid confusing terms. Appropriate terminology to differentiate the degree of surgical commitment reflects 2 levels of support5:
Surgical standby indicates a strict arrangement with an open operating room and a surgical team immediately available.
Surgical backup indicates that the cardiac surgery suites are available and emergency surgery cases may be added on to the schedule on a first-case basis.
Logistical arrangements for surgical standby or backup during PCI consist of:
On-site: Surgical facilities are physically present in the medical center facility where PCI is performed.
Off-site: Surgical facilities are present in an institution physically separated by a significant distance from the facility where PCI is performed. Timely plans and transportation arrangements are mandatory in the event that a patient requires emergency cardiac surgery for failed PCI.
From the 14% emergency surgery rate in Gruentzig’s first PTCA cohort 40 years ago,2 there have been major evolutionary reductions in the incidence of emergency surgery. The NIH-NHLBI PTCA Registry reported an emergency surgery rate of 5.8% in the years 1979 to 1981 followed by a lower rate of 3.4% in 1985 to 1986, primarily due to technical improvements and better operator experience.6 With the emergence of intracoronary stents, the incidence dropped even further in the early 2000s to reported rates of 0.14% by the Cleveland Clinic7 and 0.3% by the Mayo Clinic.8 Regardless of the low incidence of emergency surgery in these 2 studies, the mortality rate with emergency surgery continued to be high, ranging from 10% to 15%.9 A recent contemporary review from the NCDR reported emergency surgery rates of 0.18% in nonprimary PCI and 0.93% in primary PCI ST-segment elevation myocardial infarction (STEMI) patients.10
In summary, experience from the various PCI registries and literature indicates that although the incidence of emergency surgery over the years has decreased to acceptably low levels, when it does occur, the consequences of mortality and morbidity continue to remain high.
The best approach to reducing the mortality and morbidity of emergency cardiac surgery for failed PCI would be to avoid the need for emergency surgery altogether. Significant technologic improvements have occurred over the past 30 years to make PCI safer and more effective.
There has been a reduction in the French (Fr) size of guiding catheters from 8-, 9-, and 10-Fr to 7-, 6-, and even 5-Fr catheters. The guiding catheters have become much softer, decreasing the likelihood of dissection and complications at the coronary takeoff. Steerable wires have been reduced in diameter size from 0.18-inch to the current standard 0.14-inch diameter. Various soft steering wire tips are available that reduce the chance of perforation or dissection of the coronary intima. Balloon and stent delivery shaft profiles have been significantly lowered over the years from 1.4-Fr to less than 0.5-Fr diameter in a deflated state. The growth of radial artery access for PCI has resulted in the reduction of complications and bleeding.11
Along with advances in catheters, there has been a significant improvement in radiologic imaging techniques. Initially biplane fluoroscopy and angiography were thought to be the most effective ways of translating a 1-dimensional plane or imaging to at least 2 dimensions and extrapolating this to 3 dimensions. However, digital fluoroscopic and cine technology is now the standard of practice.12 This technology has markedly improved the capabilities for more precisely visualizing the coronary artery tree and various coronary angioplasty devices.
Adjunctive pharmacotherapies such as direct thrombin inhibitors, platelet glycoprotein IIb/IIIa receptor agents, and P2Y12 agents have reduced the thrombotic complications of coronary intervention and the need for emergency surgery.13
In the 1990s, the enthusiasm to lower the restenosis rate by using atheroablative devices such as directional coronary atherectomy, rotational atherectomy, transluminal extraction atherectomy, and excimer laser coronary angioplasty was tempered by a higher perforation rate and incidence of emergency surgery.14 Once experience with the devices became more extensive, the emergency surgery rate was somewhat reduced. However, a meta-analysis of multiple device trials15 confirmed the clinical impression that when atheroablative devices are compared with standard PTCA, there is no reduction in the restenosis rate and an increase in major adverse cardiac events (5.1% vs 3.3%). As a result, the widespread use of atherectomy devices has fallen out of favor and should be reserved only for very select cases.
The introduction of intracoronary stenting in the mid-1990s and eventual refinements in stent technology and pharmacology in the late 1990s resulted in a reduction in the incidence of emergency surgery by providing a more reliable solution to elastic recoil and coronary dissection.16 An analysis of the Society for Cardiovascular Angiography and Interventions Registry trends in 16,811 consecutive PCI procedures during this later era documented a 0.3% incidence of emergency surgery when stents were used compared with a 0.7% incidence (P = .002) with balloon angioplasty.17
The development of polytetrafluoroethylene (PTFE)-covered stents has provided a better option to seal coronary artery perforations. A European series demonstrated that when perforation occurred as a complication of PCI, use of a PTFE stent reduced the incidence of emergency surgery from 88% to 18%.18 In addition, even if patients went on to surgery, the PTFE stent served as a valuable supportive device and resulted in a reduction of mortality and morbidity.
The wealth of experience and data in various PCI registries has now permitted risk-adjustment scores, which indicate that hemodynamic instability, disease severity, demographics, and comorbid conditions may predict adverse outcomes.19 The strongest predictors of emergency surgery are cardiogenic shock, acute myocardial infarction (MI), emergency PCI, multivessel disease, and type C lesions.20
STRATEGIES TO REDUCE MORTALITY AND MORBIDITY WHEN EMERGENCY CARDIAC SURGERY FOR FAILED PCI OCCURS
When all attempts at a percutaneous solution have failed and emergency surgery is necessary, supporting the patient in the catheterization laboratory prior to transfer to the operating suite is crucial to reduce the already evolving higher chance of mortality and morbidity.
Coronary perfusion catheters that allow balloon inflation while still permitting coronary flow via perforated portals in the catheter shaft were an early PCI era mainstay prior to the development of intracoronary stents.21 Autoperfusion catheters are no longer made, but standard balloon dilatation catheters may be used to maintain at least partial coronary flow by alternating inflation and deflation sequences. This temporary strategy may stabilize dissected coronary flow or to stanch a perforation prior to emergency surgery in circumstances where a stent cannot be deployed. As mentioned earlier, PTFE-coated stents also may have a role in stabilizing a coronary perforation prior to going to the operating room.18
In the case of coronary perforation, attention should be paid to hematologic and hemodynamic instability. There should be a hematologic strategy to stop heparin, consider reversal with protamine, discontinue glycoprotein IIb/IIIa receptor blockers, plan for platelet transfusion, or all of the preceding.22 This must be done in coordination with the cardiac surgeons as heparin will be needed for CABG surgery. When cardiac tamponade is present, percutaneous pericardiocentesis is helpful in reducing this hemodynamic impediment prior to surgery.23
The IABP has been a mainstay to support patients with cardiovascular hemodynamic compromise who require emergency surgery. However, newer percutaneous mechanical circulatory support devices such as the nonpulsatile axial flow Archimedes screw pump (Impella; Abiomed, Danvers, MA) and extracorporeal bypass with membrane oxygenator (ECMO) may be used for catastrophic hemodynamic collapse if there is a delay to transfer to the operating room.24
The cardiac surgeon, anesthesiologist, and operating room should be alerted at the first sign that a patient may need emergency surgery. It is better to err on the side of mobilizing a room and the cardiac surgery team even though the event may eventually be controlled and surgery averted. Appropriate anesthesia backup and control of the airway are paramount in providing support of the compromised patient. Advances in surgical technique over the past 20 years have been instrumental in reducing complications following emergency surgery. Having a more stable patient as a result of the preceding support initiatives may also allow arterial conduits, such as the left internal mammary graft vessel, to be used in the emergency setting.
Lastly, with the development of hybrid catheters and operating room laboratories, extremely high-risk PCI patients may be pre-emptively managed in these suites with close surgical standby if PCI fails and emergency surgery is necessary.25
Figure 63-1 is a flow diagram of strategy options that should be considered or initiated in the catheterization laboratory to support the patient who requires emergency surgery for failed PCI.
The 2011 American College of Cardiology Foundation/American Heart Association/Society for Cardiovascular Angiography and Interventions (ACCF/AHA/SCAI) 2011 guideline13 has recommended that a mechanism of quality assurance review be established and ongoing at each institution performing PCI. Operator statistics and institutional data should be reviewed on at least a quarterly basis. Monitoring outcomes by this mechanism assures a mechanism to review cases of mortality, morbidity, or emergency surgery.
The current 2011 guidelines13 continue to recommend that PCI be performed by higher volume operators performing 75 or more cases per year (class I) and that these operators have advanced technical skills and knowledge. Subspecialty certification in interventional cardiology is a class IIa recommendation. PCI should be performed at institutions with fully equipped interventional laboratories and experienced support staff with the anticipation of performing more than 400 cases per year with an on-site cardiovascular surgical program (class I). Options for emergency cardiac surgery should be available for instances of failed PCI and instability. The guidelines recommended against low-volume operators (<75 cases per year) performing PCI who work in low-volume institutions (200-400 cases per year) with or without on-site surgical coverage (class III). An institution with less than 200 procedures per year should reconsider whether to continue to offer PCI service, unless it can be clearly documented that it is in an underserved region due to geography.13
In addressing off-site PCI centers, the 2011 guidelines gave a class IIa recommendation for primary PCI for acute STEMI and a class IIb recommendation for elective PCI if there was an appropriate backup plan and proper case selection.13 This was a major change from the previous 2005 guidelines, which gave off-site centers a class IIb indication for primary PCI and a class III indication for elective PCI.26 The current 2011 guidelines continues to advise against primary or elective PCI at off-site centers without a proven plan for rapid transport to a surgical center or without appropriate hemodynamic support strategies during transfer (class III).
