STEMI Interventions: The Finest Indication for PCI
- Volume 18 - Issue 12 - December 2010
- Posted on: 12/30/10
- 0 Comments
Can you tell us about the February 2011 LUMEN meeting, focusing on the process and the procedure of ST- elevation myocardial infarction (STEMI) interventions?
This is the 10th year for LUMEN, now converted for the third year in a row into a pure STEMI meeting. I believe it is the largest subject-centric acute myocardial infarction meeting in the world. LUMEN will be held February 24-26, at the Marriott Marquis hotel in Miami. The faculty will contain many world experts, experts both in the STEMI procedure and in the STEMI process. I am also very pleased to announce that Dr. Alice Jacobs, chairperson for the American Heart Association’s Mission: Lifeline, will be the recipient of the LUMEN achievement award in 2011.
There are several new topics. First, LUMEN will place a strong emphasis on transradial interventions. I have been struck by the increasing international rates of STEMI interventions done via the radial artery. The U.S. is lagging behind, and LUMEN will make a very sincere and determined effort to narrow this gap.
Towards that end, I have brought in some of the world’s experts in transradial interventions, including Dr. Tejas Patel, who has, over the last decade, been running the TRICO (Transradial Intervention Course) in Ahmedabad, India. Dr. Patel has trained thousands of cardiologists in the use of radial access.
Co-chairing at LUMEN with Dr. Patel will be Dr. Sunil Rao from Duke University Medical Center, a well-known authority in this field. LUMEN attendees will also benefit from the expertise of Miami-based transradial expert Dr. Ramon Quesada. The faculty will be conducting workshops, discussing tips and tricks, and providing practical lessons on radial access in STEMI interventions. Left ventricular assist devices will continue as an area of strong focus. LUMEN will also offer a look at cell therapy for STEMI interventions, with talks by Dr. Timothy Henry of Minnesota Heart, as well as Dr. Ajit Mullasari from the Madras Medical Mission, in Chennai, India, one of the most expert institutions in this area internationally. Door-to-balloon (D2B) management continues as an important focus for 2011. It will be discussed via an interactive, town hall-style meeting, conducted on the first day, with all the LUMEN co-directors. Speakers will review specific examples of STEMI interventions, pinpointing challenging areas and offering strategies for improvement.
Specific components of the STEMI procedure, particularly the management of thrombus, will be discussed. Finally, there are 8 workshops specifically tailored to the needs of the interventional cardiologist, the clinical cardiologist, the cardiac surgeon, the nurse, the cardiovascular technologist, as well as various administrators who may also benefit from attending LUMEN.
The latest Textbook of STEMI Interventions launched in November. What are some of the highlights from this second edition of the textbook?
The Textbook of STEMI Interventions discusses both the process and the procedure of STEMI interventions. It is a 650-page follow-up on the first volume. Collected within the book are 100 illustrated examples, divided into five sections: basic skills, complex interventions, thromboaspiration, rheolytic thrombectomy, and cardiogenic shock. These 100 illustrated examples provide a very large compendium of what any one operator can expect. A STEMI intervention is like a blind date. You cannot anticipate what you are going to confront, whether it is going to be significant tortuousity, the hurdles of traffic, or a dense, organized thrombus. The textbook provides a very detailed look at thrombus management. There are chapters dedicated to clinical trials, to updated American College of Cardiology/ American Heart Association-focused guidelines, improving EKG skills, pharmacology, and strategically improving D2B times. A very large section discusses what is happening internationally with STEMI interventions, presented by experts from Canada and Singapore. We hear from Dr. Antonio Colombo, who writes from the perspective of STEMI interventions in Europe, and there are details about emerging countries such as India. A substantial portion is devoted to left ventricular assist devices: one chapter addresses the pathophysiology, and another presents tips and tricks about how to benefit most from the use of left ventricular assist devices in STEMI interventions. Among many excellent authors, I am delighted to have a chapter by Dr. Derek Yellon discussing reperfusion strategies. The second edition is also a wonderful update on pharmacology, offering a chapter on IIb/IIIa inhibitors by Dr. Dean Kereiakes, a general review chapter by Dr. Raghotham Patlola and Dr. Craig Walker, a discussion of the broader aspects of pharmacology by Dr. James Ferguson, and finally, a detailed chapter on prasugrel by Dr. Mike Gibson.
The second volume of the textbook holds everything that an interventional cardiologist needs to know about STEMI interventions. The book is now available for shipping. It can be ordered through http:// www.stemiinterventions.com, and also be purchased directly at LUMEN and the upcoming American College of Cardiology meeting.
The textbook, in part, arose from the intense experience of the SINCERE database. How is the database progressing?
The Single Individual Community Experience Registry for Primary PCI (SINCERE) database is currently at 690 SHORT D2B STEMI interventions (total patients approx. 1,000, including about 30% false alarm rates) patients over almost seven years, all short D2B time interventions. The database was initially begun at 6 hospitals, now down to three, because these three hospitals have kept me extremely busy.
It was probably in the first 100-200 cases that the “10 commandments” for doing STEMI interventions were formulated (Table 1), and all 10 commandments stay true to this day. Within a specific commandment, there have been some changes, most notably that I am using much larger doses of intracoronary nitroprusside. An intracoronary vasodilator is necessary to augment the distal microvasculature flow. Numerous agents can be used for this purpose — verapamil, diltiazem, nicardipine and nitroprusside — my favorite is intracoronary nitroprusside. It does produce some hypotension, which is easily taken care of by giving bolus doses of intracoronary neosynephrine. The benefits of using an intracoronary vasodilator include a dramatic and significant increase the myocardial perfusion grade.
Intracoronary nitroprusside typically will increase perfusion grade by 1. I am now following my constructed technique in the following manner to achieve the best results with nitroprusside. I first ascertain that the PCI results and stent placement are adequate. Then I remove the guide wire (which is itself acting as a nidus of thrombus). I will then start with boluses of 50 to 100 mcg of nitroprusside, and frequently go on to use larger doses, up to even 600 and 800 mcg! Yes, this may seem alarming, and it did not come easy for me to comprehend, let alone practice. This, in turn, is the advantage of a very large, not conflicted database. In the first 200 cases in the SINCERE database, the mean dose of nitroprusside was 50 mcg, and I used it in about 30-40% of procedures. However, as my confidence grew from observing the stupendous results from this maneuver, my use of nitroprusside has significantly increased with both the frequency of use (91% presently) and in using larger doses. I have moved significantly away from the use of nitroglycerin. Nitroglycerin is more of an endothelial, nitric oxide-mediated drug. There is not much of a role of endothelium-mediated derivatives, as the problem is the presence of thrombus, which is a pathophysiological mechanism of STEMI. Both nitroglycerin and nitroprusside cause hypotension. I therefore prefer the benefit from increased distal microvasculature flow with nitroprusside, than to cause hypotension with nitroglycerin.
I continue to modify my use of bare metal versus drug-eluting stents. Recently, there have been stronger data for the use of drug-eluting stents for STEMI, although the follow up from the DEDICATION trial was somewhat tempered in its enthusiasm.1 So I think this chapter is still open, although there appears to be a larger role for drug-eluting stents. My use of drug-eluting stents in STEMI is for four indications: left anterior descending coronary artery (LAD) lesions, small vessels, long lesions, and in-stent restenosis. Beyond that, I think a lot of patients do fine with bare metal stents. We have a burgeoning population of patients with no insurance; for these patients, the cost of antiplatelet agents can be quite high, and for these patients, bare metal stents are more appealing.
I am converting more of my patients into prasugrel, because that appears to be a better drug for STEMI. The onset is quicker; you don’t have to be burdened down with clopidogrel non-responders. We use it as a bolus of 60 mg in the ER and use it for most patients, except for the elderly, those with a history of cerebrovascular accidents and those with low body weight.
I use bivalirudin on almost 100% of patients. Many trials have demonstrated it as a superior anti-thrombotic agent and it significantly reduces bleeding, which is known to be an independent predictor of mortality. I use it as a bolus and a drip; the latter is continued for up to 4 hours post procedure. It appears that the benefits of bivalirudin will get accentuated with use of transradial STEMI procedures. It also appears that any lingering doubts about stent thrombosis with bivalirudin will be completely abolished with the use of prasugrel. There has been no incidence of stent thrombus in the SINCERE database that resulted from the use of bivalirudin, although there have been three such cases that can be attributed to inadequate thrombus retrieval. Glycoprotein IIb/IIIa receptor inhibitors have been used in about 35% of SINCERE cases, always in the following situations: 1) when there is a high thrombus burden; 2) when there is residual thrombus; 3) in presence of side-branch involvement, and 4) where the angiographic result is not perfect.
In this latter situation, when there is a lack of myocardial perfusion grade (MPG) 3, continuing chest pain or residual ST elevation, I feel that a 12-hour drip of abciximab is very useful. I have also continued to use most IIb/IIIa inhibitors via direct intracoronary delivery. The Clearway catheter (Atrium Medical Corp., Hudson, New Hampshire) is the most sophisticated and probably the best way of delivering intracoronary abciximab. The true advantage of delivering intracoronary abciximab is that it achieves very high concentrations, almost 500x more than the intravenous route. At this stage, when intracoronary abciximab is locally delivered, it acts more as a de-thrombotic agent rather than as a IIb/IIIa agent.
To measure STEMI success, I have always used the following four parameters: ST segment resolution, relief of chest pain, TIMI grade 3 flow and MPG 3.