Paclitaxel- Versus Sirolimus-Eluting Stents for Unprotected Left Main Coronary Artery Disease

Long-term (4-year) outcomes and predictors of adverse cardiac events after sirolimus-eluting stent implantation in unprotected left main coronary artery

The long-term safety and efficiency of sirolimus-eluting stent (SES) treatment in unprotected left main coronary artery (ULMCA) have not yet been ascertained.From 2003 to 2006, 126 consecutive patients with de novo lesions in ULMCA who underwent SES were retrospectively analyzed in a single center in China. During 4-year follow-up, major adverse cardiovascular event (MACE)-free survival was 74.6%. Cardiac death occurred in 5 (4.0%), and target lesion revascularization (TLR) and target vessel revascularization (TVR) occurred in 15 (11.9%) and 24 (19.0%) patients, respectively. One (0.8%) experienced probable stent thrombosis while 1 (0.8%) presented possible stent thrombosis. Impaired LVEF (< 40%) and high surgical risk (Euro score > 6) were the independent predictors of MACEs.PCI with SES for de novo lesions in ULMCA is feasible with a low procedural risk. However, SES was associated with a relatively higher rate of TLR and TVR. Impaired LVEF and high surgical risk were important predictors of MACEs.

Palliative combined percutaneous balloon aortic valvuloplasty and unprotected left main stenting in end stage renal disease

With the aging population and high prevalence of atherosclerosis, an increasing number of patients presenting with heart failure and angina are found to have severe coronary artery disease and severe valvular disease. These patients tend to have multiple co-morbidities such as end stage renal disease and are considered high-risk for surgery. In patients with severe coronary artery disease, severe aortic stenosis, and heart failure with depressed left ventricular systolic function, the options are limited as they are not usually offered surgery, but palliative percutaneous high-risk procedures might be a viable alternative.

Though long term results after balloon aortic valvuolpasty are not promising, there is a role for these procedures in high-risk inoperable patients for either palliation or as a bridge to surgery. Unprotected left main percutaneous interventions are also feasible with low complication rates. This review provides mounting evidence that it is reasonable to perform combined palliative balloon aortic valvuolpasty and high-risk coronary artery stenting in certain inoperable patients. An illustrative case is presented that extends the findings of the current literature and demonstrates that combined balloon aortic valvuolpasty and left main stenting could be a safe and effective alternative in the setting of heart failure, left ventricular dysfunction, and end stage renal disease.

The herbal extract HMC05 inhibits neointima formation in balloon-injured rat carotid arteries: possible therapeutic implications of HMC05

AIM OF THE STUDY

In a previous study, HMC05, a water extract from eight medicinal herbs was demonstrated to possess anti-inflammatory effects in murine macrophages and anti-atherosclerotic effects in apoE(-/-) mice. HSP27 expression was shown to be decreased in advanced atherosclerotic plaques of human carotid arteries. In the present study, the role of HMC05 in the prevention of restenosis and the possible mechanisms involved in the decrease of neointima formation were investigated using in vivo balloon injury rat model and in vitro biochemical assays.

MATERIALS AND METHODS

A rat carotid artery balloon injury restenosis model was used. Different doses of HMC05 were administered to the rats by tube feeding, starting from four days before surgery and continuing twice per week for two weeks after carotid injury. Injured carotid arteries isolated from rats were embedded in paraffin block and tissue sections were stained with H&E to assess neointima formation. Mechanism by HMC05 that are involved in smooth muscle cell proliferation and migration was assessed by western blot assay, immunohistochemistry and confocal analysis.

RESULTS

There was no significant difference in the medial area between the control and HMC05-treated groups. However, neointima formation was significantly inhibited in the HMC05-treated group, resulting in 47-fold lower intima to media ratios in rats treated with 25 mg/kg/day HMC05 as compared to the control. Surprisingly, monocytes infiltration in the neointima area was almost completely blocked by HMC05 administration. When rat vascular SMCs were treated with HMC05, the proliferation and migration of smooth muscle cells was dramatically inhibited in a dye uptake assay and in a scratch model in a culture dish, respectively. HMC05 dose-dependently inhibited PDGF-mediated MAPK and AKT activation. However, HMC05 did not affect PDGF-mediated HSP27 phosphorylation but it induced HSP27 overexpression and phosphorylation. In addition, medial SMCs in the arterial wall of rats treated with HMC05 showed a significant increase in HSP27 expression compared with that of the control rats.

CONCLUSIONS

HMC05, a strong anti-inflammatory reagent, might use HSP27 as an effector molecule in SMCs to reduce neointimal hyperplasia by inhibiting PDGF-mediated MAPK and AKT activation. HMC05 could be a useful drug candidate for the prevention of restenosis after balloon injury of the arteries.

Drug-eluting versus bare-metal stents in unprotected left main coronary artery stenosis a meta-analysis

OBJECTIVES

We undertook a meta-analysis to assess outcomes for drug-eluting stents (DES) and bare-metal stents (BMS) in percutaneous coronary intervention for unprotected left main coronary artery (ULMCA) stenosis.

BACKGROUND

Uncertainty exists regarding the relative performance of DES versus BMS in percutaneous coronary intervention for unprotected left main coronary stenosis.

METHODS

Of a total of 838 studies, 44 met inclusion criteria (n = 10,342). The co-primary end points were mortality, myocardial infarction (MI), target vessel/lesion revascularization (TVR/TLR), and major adverse cardiac events (MACE: mortality, MI, TVR/TLR).

RESULTS

Event rates for DES and BMS were calculated at 6 to 12 months, at 2 years, and at 3 years. Crude event rates at 3 years were mortality (8.8% and 12.7%), MI (4.0% and 3.4%), TVR/TLR (8.0% and 16.4%), and MACE (21.4% and 31.6%). Nine studies were included in a comparative analysis (n = 5,081). At 6 to 12 months the adjusted odds ratio (OR) for DES versus BMS were: mortality 0.94 (95% confidence interval [CI]: 0.06 to 15.48; p = 0.97), MI 0.64 (95% CI: 0.19 to 2.17; p = 0.47), TVR/TLR 0.10 (95% CI: 0.01 to 0.84; p = 0.01), and MACE 0.34 (95% CI: 0.15 to 0.78; p = 0.01). At 2 years, the OR for DES versus BMS were: mortality 0.42 (95% CI: 0.28 to 0.62; p < 0.01), MI 0.16 (95% CI: 0.01 to 3.53; p = 0.13), and MACE 0.31 (95% CI: 0.15 to 0.66; p < 0.01). At 3 years, the OR for DES versus BMS were: mortality 0.70 (95% CI: 0.53 to 0.92; p = 0.01), MI 0.49 (95% CI: 0.26 to 0.92; p = 0.03), TVR/TLR 0.46 (95% CI: 0.30 to 0.69; p < 0.01), and MACE 0.78 (95% CI: 0.57 to 1.07; p = 0.12).

CONCLUSIONS

Our meta-analysis suggests that DES is associated with favorable outcomes for mortality, MI, TVR/TLR, and MACE as compared to BMS in percutaneous coronary intervention for unprotected left main coronary artery stenosis.

Comparison of long-term (4-year) outcomes of patients with unprotected left main coronary artery narrowing treated with drug-eluting stents versus coronary-artery bypass grafting

Percutaneous coronary intervention with drug-eluting stents (DES) may achieve midterm outcomes comparable to coronary artery bypass grafting (CABG) for unprotected left main coronary artery disease, but few real-world, long-term studies have been reported. In this study, 376 patients with unprotected left main coronary artery disease who underwent DES implantation (n = 131) or CABG (n = 245) were evaluated, and outcomes were compared using propensity analyses to adjust for baseline differences. Overall, 367 patients (98%) had complete clinical follow-up for a median of 4.0 years (interquartile range 3.2 to 4.7). Although the overall sample size was limited, there was a trend toward lower mortality with DES versus CABG in unadjusted (hazard ratio [HR] 0.50, 95% confidence interval [CI] 0.20 to 1.22, p = 0.13), multivariate-adjusted (HR 0.37, 95% CI 0.13 to 1.09, p = 0.07), and propensity score-adjusted (HR 0.34, 95% CI 0.12 to 1.03, p = 0.06) analyses. Treatment with DES was associated with a higher rate of target-vessel revascularization (TVR; 18% vs 9%, p = 0.02). However, ischemic TVR was not significantly different between the 2 groups (25% vs 39%, p = 0.15) in patients who received angiographic follow-up. No differences were detected in the occurrence of composite major adverse cardiac and cerebrovascular events between DES and CABG (27% vs 22%, p = 0.42). In conclusion, during 4-year follow-up, overall composite major adverse cardiac and cerebrovascular events were similar after DES and CABG treatment of unprotected left main coronary artery disease, with a trend toward lower mortality after percutaneous coronary intervention with DES. DES were associated with a higher rate of TVR compared to CABG, but ischemic TVR was not significantly different between the 2 groups.

Percutaneous coronary intervention for unprotected left main coronary artery stenosis

Hemodynamically significant left main coronary artery stenosis (LMCA) is found in around 4% of diagnostic coronary angiograms and is known as unprotected LMCA stenosis if the left coronary artery and left circumflex artery has no previous patent grafts. Previous randomized studies have demonstrated a significant reduction in mortality when revascularization by coronary artery bypass graft (CABG) surgery was undertaken compared with medical treatment. Therefore, current practice guidelines do not recommend percutaneous coronary intervention (PCI) for such a lesion because of the proven benefit of surgery and high rates of restenosis with the use of bare metal stents. However, with the advent of drug-eluting stents (DES), the long term outcomes of PCI with DES to treat unprotected LMCA stenoses have been acceptable. Therefore, apart from the current guidelines, PCI for treatment of unprotected LMCA stenosis is often undertaken in individuals who are at a very high risk of CABG or refuse to undergo a sternotomy. Future randomized studies comparing CABG vs PCI using DES for treatment of unprotected LMCA stenosis would be a great advance in clinical knowledge for the adoption of appropriate treatment.

Outcome in high risk patients with unprotected left main coronary artery stenosis treated with percutaneous coronary intervention

OBJECTIVE

We examined mortality, risk of myocardial infarction (MI), and target lesion revascularization (TLR) in high-risk patients with unprotected left main (LM) percutaneous coronary intervention (PCI) in Western Denmark.

BACKGROUND

PCI of left main coronary artery lesions may be an alternative to coronary artery bypass grafting in high-risk surgical patients.

METHODS

From January 2005 to May 2007, all patients who had unprotected LM PCI with stent implantation were identified in the Western Denmark Heart Registry. The indications for PCI were: (1) ST segment elevation MI (STEMI), (2) non-STEMI (NSTEMI) or unstable angina, and (3) stable angina. All patients were followed up for 18 months.

RESULTS

A total of 344 patients were treated with LM PCI (STEMI: 71, NSTEMI/unstable angina: 157, and stable angina: 116). In STEMI patients, the median logistic EuroSCORE was 22.5 (interquartile range 12.5-39.5), in non-STEMI (NSTEMI)/unstable angina patients 13.8 (4.8-23.9), and in stable angina patients 4.8 (2.2-10.4). Mortality after 18 months 38.0, 18.5, and 11.2% (P < 0.001) in patients with STEMI, NSTEMI/unstable angina, and stable angina, respectively. MI after 18 months was 9.9, 6.4, and 6.0% (P = ns), respectively. Four subacute and one late definite stent thrombosis were seen. TLR occurred in 5.6, 4.5, and 6.9% (P = ns) of patients, respectively.

CONCLUSION

After PCI, patients with STEMI and LM culprit lesion have a high-mortality risk, whereas long-term outcome for patients with NSTEMI and stable angina pectoris is comparable with other high surgical risk patients with unprotected left main lesion. Further, TLR rates and risk of stent thrombosis were low.

Long-term outcome of percutaneous catheter intervention for de novo coronary bifurcation lesions with drug-eluting stents or bare-metal stents

BACKGROUND

The purpose of this study was to assess the long-term risks and benefits of drug-eluting stents (DESs) compared with bare-metal stents (BMSs) for treatment of coronary bifurcation lesions.

METHODS

Our registry comprised 1,038 patients treated for coronary bifurcation lesion according to the provisional T-stenting strategy who were followed up for 3 years.

RESULTS

Target lesion revascularization rates were 24.3% for BMSs (n = 337), 15.6% for sirolimus-eluting stents (SESs, n = 422), and 17.3% for paclitaxel-eluting stents (PESs, n = 279) (P = .003 BMSs vs DESs, P = .54 SESs vs PESs). The respective incidences were 11.4%, 9.5%, and 14.8% (P = .65, P = .13) for death and myocardial infarction and 9.9%, 6.5%, and 10.6% (P = .72, P = .19) for death. Propensity score adjusted hazard ratios (95% CI) for DESs versus BMSs were 0.49 (0.35-0.68, P < .001) for target lesion revascularization, 0.94 (0.64-1.40, P = .078) for death and myocardial infarction, and 0.85 (0.55-1.32, P = .47) for death. We did not find any significant differences between SESs and PESs, except for an increased risk of death after PESs compared with SESs (but not BMSs) in the subgroup receiving a side-branch stent (adjusted hazard ratio 2.45, 95% CI 1.05-5.73, P = .035).

CONCLUSIONS

Compared with BMSs, both PESs and SESs substantially reduced the long-term need for repeated revascularization but did not increase the risk of death and myocardial infarction.

High residual platelet reactivity after clopidogrel loading and long-term clinical outcome after drug-eluting stenting for unprotected left main coronary disease

BACKGROUND

No data exist about the impact of high residual platelet reactivity (HRPR) after clopidogrel loading on long-term clinical outcome in patients undergoing drug-eluting stent (DES) implantation for unprotected left main disease (ULMD).

METHODS AND RESULTS

Consecutive patients who underwent percutaneous coronary intervention for ULMD had prospective platelet reactivity assessment by light transmittance aggregometry after a loading dose of 600 mg of clopidogrel. The primary end point of the study was cardiac mortality, and the secondary end point was stent thrombosis. From January 2005 to September 2008, 215 consecutive patients were treated with DES for ULMD. The incidence of HRPR after clopidogrel loading was 18.6%. The median follow-up was 19.3 months. The overall estimated 1-, 2- and 3-year cardiac mortality rate was 3.9+/-1.3%, 7.5+/-2.2%, and 12.2+/-3.4%, respectively. The 3-year cardiac mortality rate was 8.0+/-3.1% in the low residual platelet reactivity (LRPR) group and 28.3+/-10.4% in the HRPR group (P=0.005). The 3-year stent thrombosis rate was 4.2+/-1.8% in the low residual platelet reactivity group and 16.0+/-7.3% in the HRPR group (P=0.021). By forward stepwise regression analysis, HRPR after clopidogrel loading was the only independent predictor of cardiac death (hazard ratio, 3.82; 95% confidence interval,1.38 to 10.54; P=0.010) and stent thrombosis (hazard ratio, 3.69; 95% confidence interval, 1.12 to 12.09; P=0.031).

CONCLUSIONS

HRPR after 600-mg clopidogrel loading is a strong marker of increased risk of cardiac death and DES thrombosis in patients receiving DES stenting for ULMD. Routine assessment of in vitro residual platelet reactivity after clopidogrel loading in patients with ULMD potentially suitable for DES-supported percutaneous coronary intervention should be considered to guide patient care decisions.

C-peptide fragments stimulate glucose utilization in diabetic rats

Studies of C-peptide cellular effects show that not only the full-length native peptide but also specific C-terminal fragments are biologically active in in vitro systems. In the present study, the effect of five C-peptide fragments and the native peptide on whole-body glucose turnover was studied in streptozotocin diabetic rats using the insulin clamp technique. Insulin was infused intravenously at 18 pmol kg(-1) min(-1) for 90 min and blood glucose concentration was clamped at 8 and 4 mM in diabetic and non-diabetic animals. A steady state was reached during the last 30 min of the study period. Rat C-peptide II and fragments comprising residues 27-31 and 28-31 were effective in augmenting glucose turnover in diabetic rats (+100% to 150%), while no significant effects were seen for segments 1-26, 11-19 and 11-15. The metabolic clearance rate for glucose during infusion of C-peptide or fragments 27-31 and 28-31 in diabetic rats was similar to that seen in non-diabetic animals. We conclude that C-terminal tetra- and pentapeptides, but not fragments from the middle segment of C-peptide, are as effective as the full-length peptide in stimulating whole-body glucose turnover in diabetic rats.