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Three Part Question

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

Clinical Scenario

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.

Search Strategy

Medline 1995 to Aug 2007 using Ovid Interface


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

Search Outcome

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

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
ACC/AHA/SCAI guidelines, 2005, USA	Report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines Practice guideline group consisted entirely of cardiologists from the 3 organisations involved.	Guideline (Level 2a)	Guidance	CABG using IMA grafting is the “gold standard” for treatment of ULM disease and has proven benefit on long-term outcomes. The use of DES has shown encouraging short-term outcomes, but long-term follow-up is needed. Nevertheless, the use of PCI for patients with significant ULM stenosis who are candidates for revascularization but not suitable for CABG can improve cardiovascular outcomes and is a reasonable revascularization strategy in carefully selected patients PCI is not recommended in patients with asymptomatic ischemia or CCS class I or II angina, Left main disease and eligibility for CABG Use of PCI is reasonable in patients with CCS class III angina with significant left main CAD (greater than 50% diameter stenosis) who are candidates for revascularization but are not eligible for CABG. (Level of Evidence: B) PCI is not recommended for patients with CCS class III angina and significant left main CAD and candidacy for CABG. (Level of Evidence: C) Use of PCI is reasonable in patients with UA/NSTEMI with significant left main CAD (greater than 50% diameter stenosis) who are candidates for revascularization but are not eligible for CABG. (Level of Evidence: B) In patients with cardiogenic shock and significant left main disease or severe 3-vessel disease and without right ventricular infarction or major comorbidities such as renal insufficiency or severe pulmonary disease, CABG can be considered as the revascularization strategy
Silber et al, European Society for Cardiology guidelines 2005,	Report of the European Society of Cardiology	Guidelines (level 2a)	Guidance	The presence of a left main(LM) coronary artery stenosis identifies an anatomic subset still requiring bypass surgery for revascularization. PCI of protected LMS ( i.e. by a distal graft) can be performed although a 1-year MACE of 25% is still rather high, which may reflect an increased mortality in patients with severe CAD with previous CABG. Stenting for unprotected LM disease should only be considered in the absence of other revascularization options. Therefore,PCI can be recommended in these subsets when bypass surgery has a very high perioperative risk(e.g. EuroSCORE>10%). Until proved otherwise, PCI should be used only with reservation in diabetics with multi-vesseld disease and in patients with unprotected left main stenosis.
Erglis et al, 2007, Australia and Latvia	103 patients with unprotected LMS disease, 2004-2006 All patients were good candidates for CABG Randomized to Express or Liberte BMS or Paclitaxel Eluting Stent (PES) with cutting balloon pre-treatment under IVUS control Clopidogrel, Heparin, GpIIb/IIIa given BMS n=50 PES n=53	PRCT(Level 1b)	Myocardial Infarction by 6 months	BMS 7/50 (14%). PES 5/53 (10%)	Patient population is those also ideal for surgery Mean Age 62 Only 6 had prev CABG, mean LVEF 54%
			Restenosis	BMS 11/50pts (22%) PES 3/53pts (6%) P=0.021
			6mth adverse cardiac-event free survival	BMS 15/50 (30%) PES 7/53 (13%) P=0.036
			Mortality at 6 months	BMS and PES 1pt each ( 2%)
Ellis SG 1997, USA	107 patients treated for LMS disease from 16 centres. These patients represented 0.2% of all procedures performed in these hospital. 27% were inoperable 30% high risk for surgery 15% prev CABG 15% acute MI Age mean 66 50% BMS 24% atherectomy 20% balloon angioplasty All had aspirin, 26 Ticlopidine, 2 abciximab Follow up 15+/-8 months	Cohort study (Level 2b)	In Hospital results	4 deaths in Cath lab 20% in hospital death 10% Q wave MI 5% CABG	Very small numbers from each centres.
			Event free survival	88.8 +/-3.5% at 1 month. 72.6+/-5% at 6 months. 71+/-5% at 12 months
			> 4 month angioplasty	22% had restenosis
Palmerini et al, 2006, Italy	154 patients underwent CABG and 157 patients underwent PCI for left main stenosis (94 DES) From 2002-2005 Mean age±SD: CABG 69.3±9.5 PCI 73.0±10.9 Left main disease alone: CABG 5.2% PCI 12.7% p<0.001 Left main lesions locations: p=0.742 Follow-up: 430 days (105-730)	Prospective cohort study (Level 2b)	30 days	Overall Mortality: CABG 4.5% PCI 3.2% p=NS Cardiac related mortality: CABG 3.9% PCI 2.5% p=NS Myocardial infarction at 30 days: CABG 1.9% PCI 4.5% p=NS Target Lesion Revascularisation: CABG 0.6% PCI 0.6% p=NS	-short term follow up -early and long-term mortality were not significantly different between CABG and PCI -target lesion revascularization was significantly higher in PCI-treated patients - although patients treated with drug-eluting stents had a 25% relative risk reduction in the rate of major adverse cardiac events compared with patients treated with bare metal stents, event survival was still higher in the CABG group than in the drug eluting stent group
			Follow-up	Overall Mortality: CABG 12.3% PCI 13.4% p=0.861 CABG 12.3% PCI-DES 11.7% p=0.968 Cardiac related mortality: CABG 9.7% PCI 9.5% p=0.994 CABG 9.7% PCI-DES 7.4% p=0.667 Myocardial infarction: CABG 4.5% PCI 8.3% p=0.170 CABG 4.5% PCI-DES 5.3% p=0.690 Target lesion revascularisation: CABG 2.6% PCI 25.5% p=0.0001
Chieffo et al, 2006, Italy	142 patients underwent CABG (86 patients had on-pump CABG, 56 patients underwent off-pump CABG) 107 patients underwent PCI-DES for left main stenosis (2002-2004) 81.3% of patients treated with PCI had distal LMCA Mean age±SD: CABG 67.5±9.7 PCI 63.6±10.3 Renal failure: CABG 8.4% PCI 1.9% p=0.02 Follow-up: 1 year	Prospective Cohort Study (level 2b)	30 days	Mortality: CABG 2.1% PCI 0 Myocardial infarction: CABG 26.5% PCI 9.3% p=0.0009 Q-wave MI: CABG 3.5% PCI 0 p=0.07 Target lesion revascularisation: CABG 2.1% PCI 0 TVR: CABG 2.1% PCI 0	The patients receiving DES were significantly younger than CABG patients ( 64 vs 68yrs) Had lower incidence of smoking, significantly less hypertension , less diabetes, and significantly less renal failure. The PCI patients were therefore fitter than the CABG patients 26% Perioperative MI rate after CABG is incredibly high, due to their definition of MI.
			Follow-up	Mortality: CABG 6.4% PCI 2.8% p=0.07 Myocardial infarction: CABG 1.4% PCI 0.9% Target lesion revascularisation: CABG 3.6% PCI 15.8% p=0.001 TVR: CABG 3.6% PCI 19.6% p=0.0001
Lee et al, 2006, USA	123 patients underwent CABG and 50 patients PCI with DES for left main stenosis (2003-2006) Mean age±SD: CABG 70 ± 10 PCI 72 ± 15 Parsonnet score: CABG 13.7 ± 9.7 PCI 18.3 ± 10.9 p<0.01 Follow-up: CABG 6.7 ± 6.2 months PCI 5.6 ± 3.9	Prospective cohort study (Level 2b)	30 days	Mortality: CABG 5% PCI 2% p=0.34 Myocardial infarction: CABG 2% PCI 0 p>0.9 Target vessel revascularisation: CABG 1% PCI 0 p>0.9 In-hospital length of stay (days mean±SD): CABG 7.6 ± 4.9 PCI 3.9 ± 4.5	-PCI with DES is a viable alternative to CABG for treatment of left main coronary artery when clinical judgment was used for patients allocation -there may be an incidence of late complications associated with DES that will be defined with a longer-term follow-up
			Follow-up (Kaplan-Meier)	Freedom from Mortality: 6 months: CABG 87% PCI 96% p=0.861 1 year: CABG 85% PCI 96% p=0.18 Freedom from TVR: 6 months: CABG 99% PCI 93% 1 year: CABG 93% PCI 87% p=0.22 Target lesion revascularisation: CABG 3.6% PCI 15.8% p=0.001 TVR: CABG 3.6% PCI 19.6% p=0.0001
Tan et al, 2001, Europe, Japan, Korea	279 patients who had ULMS PCI from 1 of 25 sites of multicenter study (1993-1998) 46% of patients were deemed inoperable or at high surgical risk 50% had a post procedure IABP Follow-up: 1 year, (97.1% complete)	Prospective multicenter cohort study (level 2b )	Mortality at 30/7	13.7%	Complete data regarding RCA are unavailable CABG is the first choice for ULMS PCI is a viable option in AMI, inoperable patients or low-risk patients
			Follow up	Mortality 12.2% Cardiac related mortality 9.1% AMI 8.7% CABG 8.7%
Kelley et al, 2003, USA-France	Retrospective cohort study (Level 2b)	142 patients treated with BMS for LMS (1997-2003) 99 patients with protected LMS 43 patients with ULMS ULMS cohort had significant higher age and percentage of AMI and 20% were in cardiogenic shock MACE: death + non fatal MI+TLR Follow-up: 1 year (96% complete)	Mortality at 30/7	LMS 2.1% ULMS 9.3%	- Stenting for unprotected LMCA disease in a high risk population is associated with a poor one-year survival and should only be considered in the absence of other revascularization options - BMS procedure for protected LMCA disease is still associated with increased mortality and MACE rates compared to PCI of other coronary lesions
			Follow up	Mortality LMS 5% ULMS 28% p<0.0001 MI LMS 3% ULMS 7% Target lesion revascularisation LMS 18% ULMS 23% MACE LMS 25% ULMS 49%p=0.005
Valgimigli et al, 2005, Italy-The Netherlands	181 patients underwent PCI for LMS (2002-2003) 95 patients were treated with DES (52 SES, 43 PES) 2 cohorts BMS (86 patients) and DES (95 patients) with no differences in clinical features higher prevalence of 3-vessel disease and bifurcation stenting in the DES group Follow-up: mean 503 days (range 331 – 873)	Retrospective cohort study (Level 2b)	Mortality at 30/7	BMS 7% DES 11%	-The use of DES as a default strategy to treat LM disease was associated with a significant reduction in adverse events -CABG should remain the preferred revascularization treatment in good surgical candidates presenting with LM coronary artery disease
			MI at 30/7	BMS 9% DES 4%
			Target vessel revascularisation at 30/7	BMS 2% DES 0
			Follow up Mortality	BMS 16% DES 14%
			AMI	BMS 12% DES 4% p=0.006
			Target vessel revascularisation	BMS 23% DES 6% p=0.004
Agostoni et al, 2005, The Netherlands	58 patients electively treated for ULMS (2002-2003) 24 procedures with IVUS aid FU: mean 433 days (range 178 – 780)	Retrospective cohort study (Level 2b)	Mortality at 30/7	3%	-When ostial or mid-LM disease is treated with DESs, the rate of cardiac events is particularly low -In patients with distal LM involvement, the rate of events was significantly higher, but also in this instance, no significant clinical benefit occurred in the IVUS subgroup.
			Follow up	Mortality 5% AMI 3% Target vessel revascularisation 7%
Park et al, 2003, North Korea	1995-2000, 270 consecutive patients with unprotected LMS and normal LV at 4 centres Mean Follow up 32 +/-18 months Mean Age 61yrs	Cohort study (level 2b )	Hospital Complications	3 stent thromboses, 3 Q-Wave MIs No deaths 3 emergency CABG	Pre-DES era
			Angiographic follow up	Restenosis rate 21.1%
			Deaths over mean 3 yrs	20 deaths 8 cardiac deaths
			Target vessel revascularization	45pts (17%)
			3 year freedom from major cardiac events	77.7% +/- 2.7%
Lee et al, 2007, USA	123 patients underwent CABG and 50 patients PCI with DES for left main stenosis (2003-2006) Mean age±SD: CABG 70 ± 10 PCI 72 ± 15 Parsonnet score: CABG 13.7 ± 9.7 PCI 18.3 ± 10.9 p<0.01 Follow-up: CABG 6.7 ± 6.2 months PCI 5.6 ± 3.9	Prospective cohort study (Level 2b)	Mortality 30/7	CABG 5% PCI 2% p=0.34	-PCI with DES is a viable alternative to CABG for treatment of left main coronary artery when clinical judgment was used for patients allocation -there may be an incidence of late complications associated with DES that will be defined with a longer-term follow-up
			Myocardial infarction 30/7	CABG 2% PCI 0 p>0.9
			Target vessel revascularisation 30/7	CABG 1% PCI 0 p>0.9
			In-hospital length of stay (days mean±SD)	CABG 7.6 ± 4.9 PCI 3.9 ± 4.5
			Follow-up Freedom from Mortality	6 months: CABG 87% PCI 96% p=0.861 1 year: CABG 85% PCI 96% p=0.18
			Freedom from TVR	6 months: CABG 99% PCI 93% 1 year: CABG 93% PCI 87% p=0.22
			Target lesion revascularisation	CABG 3.6% PCI 15.8% p=0.001
			TVR	CABG 3.6% PCI 19.6% p=0.0001
Price et al, 2006, USA	50 patients with Unprotected Left Main Stenosis who had a Sirolimus Eluting Stent. Patients too high risk for CABG or refused CABG 58% had Euroscore predicted mortality > 5% Repeat angiography at 3 and 9 months	Cohort study(level 2b)	In-lesion restenosis	21/50 ( 42%)	84% bifurcational LMS stenting.
			Target lesion revascularization	19 (38%)
			Death	5 (10%)
			MACE, death, MI, TLR, Thrombosis	22/50 ( 44%
Jonsson et al, 2006, Sweden	1888 patients who had CABG for LM stenosis from (1970-1999) 8759 patients undergone CABG for coronary disease with no LM Follow-up: 5 years	Retrospective cohort Study (level 2b)	30 days	Mortality (1970-1999): Overall LM 2.7% No LM 2%. Males LM 2.2% No LM 1.9%. Females LM 4.7% No LM 2.6%	During the period 1970-1999 there was a decrease of early and five year mortality in patients with LM after CABG despite increases of patient age and risk factors. An increased risk of early and late deaths after CABG in patients with LM stenosis compared with patients without LM stenosis in the 1970s and 1980s was neutralised during the 1990s. There has been an improvement of peri- and postoperative management of patients undergoing CABG during this time period.
			Follow-up	5 year mortality: Overall LM 10% No LM 8.1% Males LM 10.1% No LM 8.2% Females LM 9.6% No LM 7.8%

Comment(s)

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.

Editor Comment

BMS: bare metal stent; BS: bifurcation stenting; DES: drug eluting stent; LMCA: left main coronary artery; MACE: major cardiac events; PCI: percutaneous coronary intervention; TLR: target lesion revascularization; SVS: single vessel stenting; TVR: target vessel revascularization; ULMS: unprotected left main stenosis.

Clinical Bottom Line

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.

References

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 J Am Coll Cardiol 2006;47(1):216-35.
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. Eur Heart J 2005;26:804-47.
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. J Am Coll Cardiol 2007;50(6):491-7.
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. Circulation 1997;96(11):3867-72.
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). Am J Cardiol 2006;98(1):54-9.
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]. Circulation 2006;113(21):2542-7.
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]. J Am Coll Cardiol 2006;47(4):864-70.
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]. Circulation 2001;104(14):1609-14.
9. Kelley MP, Klugherz BD, Hashemi SM et al. One-year clinical outcomes of protected and unprotected left main coronary artery stenting. Eur Heart J 2003;24(17):1554-9.
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) Am Heart J 2006;152(5):896-902.
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]. Circulation 2005;111(11):1383-9.
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. Am J Cardiol 2005;95(5):644-7.
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. Am J Cardiol 2003;91:12-6.
14. Park SJ, Kim Y-H, Lee B-K et al. Sirolimus-Eluting Stent Implantation for Unprotected Left Main Coronary Artery Stenosis. J Am Coll Cardiol 2005;45(3):351-6.
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. International Journal of Cardiology 2007;115:208-13.
16. Price MJ, Cristea E, Sawhney N et al. Serial Angiographi follow-up of sirolimus eluting stents for unprotected left main coronary artery revascularization. J Am Coll Cardiol 2006;47(4):871-7.
17. Beohar N, Davidson CJ, Kip KE et al. Outcomes and Complications Associated With Off-Label and Untested Use of Drug-Eluting Stents. J Am Coll Cardiol 2007;297(18):2001-28.
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. Eur J Cardiothorac Surg 2006;30(2):311-7.