For which patients with left main stem disease is Percutaneous Intervention rather than Coronary Artery Bypass Grafting the better option ?

April 23, 2008

March 12, 2009

Pietro Giorgio Malvindi, Joel Dunning, Nicola Vitale, Specialist Registrars in Cardiothoracic Surgery (Department of Cardiac Surgery, Policlinico Hospital, University of Bari, Italy)

Joel Dunning, Department of Cardiac Surgery, Policlinico Hospital, University of Bari, Italy

In a [patient with left main stem coronary disease] does [percutaneous stenting or CABG] result in the best [long- term survival].

You are asked by the interventional cardiologist on-call to discuss a 73 year old gentleman still on the table in the angiography lab. He was admitted with a non-ST myocardial infarction with a small troponin rise, has had clopidogrel, aspirin and reopro and is currently stable. The coronary angiogram shows a tight proximal left main stem lesion of about 70%. The patient is mildly obese and diabetic with some varicosities of the left leg and has prostate carcinoma which is currently well controlled. The cardiologist would like to stent this lesion if you thought that he was not a good surgical candidate and asks for your opinion.

Medline 1995 to Aug 2007 using Ovid Interface

[LMS.mp or left main.mp] AND [exp Angioplasty/ OR angioplasty.mp]

Using the reported search, 665 papers were identified from which 15 papers provided the best evidence to answer the question. These are summarized in the Table

In 2005 the ACC/AHA Task Force on Practice Guidelines updated their guidelines for percutaneous intervention. They provided extensive guidance for patients with left main stem disease. They reiterate that CABG remains the gold standard for the treatment of the unprotected left main coronary artery. PCI should only be considered for patients with or without angina if the patient is a candidate for revascularization but who is not eligible for CABG. They further state that patients with unstable angina or NSTEMI with cardiogenic shock and left main stem disease should still undergo CABG.
The European Society of Cardiology Task force for percutaneous interventions also published practice guidelines in 2005. They recommended that patients with left main stem disease or diabetics with multivessel disease undergo CABG rather than PCI. They additionally state that PCI could be contemplated in patients with a prohibitively high risk and cited a EuroSCORE risk of over 10% as a guide figure. Of note, in the UK we now perform at around half the Euroscore and thus a risk of 10% for CABG would equate to a Euroscore of approaching 20.
The most recent study is by Erglis published in August 2007. They performed an RCT of Paclitaxel-eluting stent versus bare-metal stent in 103 pts who were also good candidates for CABG with mean EF 54%. There were no immediate procedural complications. The 6-month mortality was 2% in both groups. MI rate at 6-months was 14% for BMS and 9% for PES. MACE at 6-months was 30% for BMS and 13% for PES.
Ellis reported the results of 107 patients not eligible for CABG who had LMS disease prior to 1997. Survival was 70% at 12 months and of those who survived to 4 months for an angiogram, 20% had restenosis greater than 50%. 50% of these patients had BMS, with the remainder having angioplasty or atherectomy.
Palmerini reported a contemporary cohort study of patients with LMS disease. 154 patients underwent CABG and 157 patients PCI. On mean follow up of just over a year, 25% of patients undergoing PCI required target vessel revascularization compared to 2.6% in the CABG group(p=0.0001), and 8.3% had an MI compared to 4.5%(p=0.17). 1-year PCI mortality was 13%.
Chieffo reported a similar cohort of LMS patients. 142 patients were treated with CABG and 107 a DES during PCI. Of note the PCI patients were younger, had less diabetes, hypertension and smoking then CABG patients. Also the perioperative-MI rate of the CABG patients was reported as 26% at 30-days which seems extraordinary. At 1 year there was a 20% revascularization rate with PCI versus 3.6% for CABG. There was no mortality or MI difference at 1 yr. Mortality in the PCI group was 2.8% at 1-year in this group of patients with a mean euroscore of 4.4.
Lee published results of patients with LMS disease followed up for 6-months. The only significant differences between the 123 patient CABG group and the 50 patient DES-PCI group was for target vessel revascularization (CABG 3.6%; DES 19.6%; p=0.0001). Mortality and MI rates were similar. Mortality from PCI was 4% at 6 months in this group with mean parsonnet score of 18.
Tan reported their results of BMS-PCI in 279 patients deemed too high risk for CABG from 25 centres. The 1-year mortality/MI/CABG rate in the PCI group was 24% and death was 12%. Their risk scores were not given but 20% were in cardiogenic shock at PCI and 50% had an IABP.
Kelley evaluated clinical outcomes of protected and unprotected left main coronary bare metal stenting in patients unsuitable for CABG. At 1-yr 43 ULMS stents had a 28% mortality and 48% MACE.
Valgimigli assessed clinical outcomes of left main stem stenting with 86 DES and 95 BMS patients over a mean of nearly 2 years. There were significant higher rates of myocardial infarction (DES 4%; BMS 12%; p = 0.006) and target vessel revascularization (DES 6%; BMS 23%, p = 0.004) for BMS. Mortality at a mean 2 years was DES 14% and BMS 16%. Mean Parsonnet in the DES group was 19.
Agostoni achieved a 2-year mortality of only 5% in 58 patients undergoing PCI for LMS disease.
Price reported the angiographic findings of LMS stenting with a serolimus stent in 50 patients. At 9 months, 38% required revascularization and there was a 44% MACE.
LMS stenting is also not being commonly performed. In a registry of current practice of 7752 patients undergoing PCI treated in 140 centres over 6-months in 2005, 90% received drug-eluting stents but only 110 patients had LMS stenting (2%)[18].
The results of surgery of left main stenosis were reviewed by Jonsson. They compared 1888 patients who underwent CABG for left-main stenosis with 8759 patients who had CABG for coronary disease without left-main disease. During 1970-1984 early mortality was 5.8% in patients with left-main stenosis vs1.5% in patients without left-main stenosis. The corresponding rates during 1995-1999 were 2.0%vs2.2%. Five-year survival in males with left-main stenosis was 88% after operations performed during 1994-1999. The continuous decline of mortality during three decades most likely reflects improvement of the peri- and postoperative management of patients undergoing CABG during this period.

If a bare metal stent is used for left main stanting the mortality at 1 year may be from 3% to over 28% in reported series. The restenosis rate of the bare metal stent in the left main position is around 20% at a year. There are some early series and RCTs of drug eluting stents for LMS lesions and the restenosis rate is reported to be around 10%. The European Society of Cardiology in their 2005 PCI guidelines state that CABG is the procedure of choice for left main stem disease and only patients with a prohibitively high surgical risk should be considered. We consider that with such prohibitively high restenosis rates, and with short term follow-up in such low numbers and short periods compared to coronary artery bypass grafting, left main stenting should only be used as a last resort in patients turned down for coronary artery bypass grafting after full assessment by a cardiac surgeon due to prohibitive co-morbidities.

1. Smith SC Jr,Feldman TE,Hirshfeld JW Jr et al. ACC/AHA/SCAI 2005 Guideline Update for Percutaneous Coronary Intervention-Summary Article. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (A
2. Silber S, Albertson P, Aciles FF et al.. Guidelines for Percutaneous Coronary Interventions. The Task Force for Percutaneous Coronary Interventions of the European Society of Cardiology.
3. Erglis A, Narbute I, Kumsars I et al.. A Randomized Comparison of Paclitaxel-Eluting Stents Versus Bare Metal Stents for Treatment of Unprotected Left Main Coronary Artery Stenosis.
4. Ellis SG, Tamai H, Nobuyoshi M et al.. Contemporary Percutaneous Treatment of Unprotected Left Main Coronary Stenoses : Initial Results From a Multicenter Registry Analysis 1994-1996.
5. Palmerini T, Marzocchi A, Marrozzini C et al.. Comparison between coronary angioplasty and coronary artery bypass surgery for the treatment of unprotected left main coronary artery stenosis (the Bologna Registry).
6. Chieffo A, Morici N, Maisano F et al.. A. Percutaneous treatment with drug-eluting stent implantation versus bypass surgery for unprotected left main stenosis: a single-center experience.[see comment].
7. Lee MS, Kapoor N, Jamal F et al.. Comparison of coronary artery bypass surgery with percutaneous coronary intervention with drug-eluting stents for unprotected left main coronary artery disease.[see comment].
8. Tan WA, Tamai H, Park SJ et al.. Long-term clinical outcomes after unprotected left main trunk percutaneous revascularization in 279 patients.[see comment].
9. Kelley MP, Klugherz BD, Hashemi SM et al.. One-year clinical outcomes of protected and unprotected left main coronary artery stenting.
10. Valgimigli M, Malagutti P, Rodriguez Granillo GA et al. Single-vessel versus bifurcation stenting for the treatment of distal left main coronary artery disease in the drug-eluting stenting era.. Clinical and angiographic insights into the Rapamycin-Eluting Stent Evaluated at Rotterdam Cardiology Hospital (RESEARCH) and Taxus-Stent Evaluated at Rotterdam Cardiology Hospital (T-SEARCH)
11. Valgimigli M, van Mieghem CA, Ong AT et al. Short- and long-term clinical outcome after drug-eluting stent implantation for the percutaneous treatment of left main coronary artery disease:. insights from the Rapamycin-Eluting and Taxus Stent Evaluated At Rotterdam Cardiology Hospital registries (RESEARCH and T-SEARCH).[see comment].
12. Agostoni P, Valgimigli M, van Mieghem CA et al.. Comparison of early outcome of percutaneous coronary intervention for unprotected left main coronary artery disease in the drug-eluting stent era with versus without intravascular ultrasonic guidance.
13. Park SJ, Park S-W, Hong M-K et al.. Long-term (Three-year) Outcomes after stenting of unprotected left main coronary artery stenosis in patients with normal left ventricular function.
14. Park SJ, Kim Y-H, Lee B-K et al.. Sirolimus-Eluting Stent Implantation for Unprotected Left Main Coronary Artery Stenosis.
15. Lee B-K, Hong M-K, Lee CW et al.. Five-year outcomes after stenting of unprotected left main coronary artery stenosis in patients with normal left ventricular function.
16. Price MJ, Cristea E, Sawhney N et al.. Serial Angiographi follow-up of sirolimus eluting stents for unprotected left main coronary artery revascularization.
17. Beohar N, Davidson CJ, Kip KE et al.. Outcomes and Complications Associated With Off-Label and Untested Use of Drug-Eluting Stents.
18. Jonsson A, Hammar N, Nordquist T et al.. Left main coronary artery stenosis no longer a risk factor for early and late death after coronary artery bypass surgery--an experience covering three decades.