Comparison of Bare-Metal Stenting With Minimally Invasive Bypass Surgery for Stenosis of the Left Anterior Descending Coronary Artery

Minimally Invasive Coronary Artery Bypass Grafting for Multivessel Coronary Artery Disease: A Systematic Review

OBJECTIVE

We conducted a systematic review of all available evidence on the feasibility and safety of minimally invasive coronary artery bypass grafting (MICS CABG) in patients with multivessel coronary artery disease (CAD).

METHODS

A systematic literature search in PubMed, MEDLINE via Ovid, Embase, Scopus, and Web of Science was performed to identify all relevant studies evaluating outcomes of MICS CABG among patients with multivessel CAD and including at least 15 patients with no restriction on the publication date.

RESULTS

A total of 881 studies were identified, of which 26 studies met the eligibility criteria. The studies included a total of 7,556 patients. The average patient age was 63.3 years (range 49.5 to 69.0 years), male patients were an average of 77.8% (54.0% to 89.8%), and body mass index was 29.8 kg/m2 (24.5 to 30.1 kg/m2). Early mortality and stroke were on average 0.6% (range 0% to 2.0%) and 0.4% (range 0% to 1.3%), respectively. The average number of grafts was 2.8 (range 2.1 to 3.7). The average length of hospital stay was 5.6 days (range 3.1 to 9.3 days).

CONCLUSIONS

MICS CABG appears to be a safe method in well-selected patients with multivessel CAD. This approach is concentrated at dedicated centers, and there is no widespread application, although it has potential to be widely applicable as an alternative for surgical revascularization. However, large randomized controlled studies with longer follow-up are still required to compare the outcomes with conventional CABG and other revascularization strategies.

Long-term follow-up of patients with complex coronary artery disease treated with minimally invasive direct coronary artery bypass

BACKGROUND

Patients with complex coronary artery disease (CAD) may benefit from surgical myocardial revascularization but weighing the risk of peri-operative complications against the expected merit is difficult. Minimally invasive direct artery bypass (MIDCAB) procedures are less invasive, provide the prognostic advantage of operative revascularization of the left anterior descending artery and may be integrated in hybrid strategies. Herein, the outcomes between patients with coronary 1-vessel disease (1-VD) and patients with 2-VD and 3-VD after MIDCAB procedures were compared in this single-center study.

METHODS

Between 1998 and 2018, 1363 patients underwent MIDCAB at the documented institution. 628 (46.1%) patients had 1-VD, 434 (31.9%) patients 2-VD and 300 (22.0%) patients suffered from 3-VD. Data of patients with 2-VD, and 3-VD were pooled as multi-VD (MVD).

RESULTS

Patients with MVD were older (66.2 ± 10.9 vs. 62.9 ± 11.2 years; p < 0.001) and presented with a higher EuroScore II (2.10 [0.4; 34.2] vs. 1.2 [0.4; 12.1]; p < 0.001). Procedure time was longer in MVD patients (131.1 ± 50.3 min vs. 122.2 ± 34.5 min; p < 0.001). Post-operatively, MVD patients had a higher stroke rate (17 [2.3%] vs. 4 [0.6%]; p = 0.014). No difference in 30-day mortality was observed (12 [1.6%] vs. 4 [0.6%]; p = 0.128). Survival after 15 years was significantly lower in MVD patients (p < 0.01). Hybrid procedures were planned in 295 (40.2%) patients with MVD and realized in 183 (61.2%) cases. MVD patients with incomplete hybrid procedures had a significantly decreased long-term survival compared to cases with complete revascularization (p < 0.01).

CONCLUSIONS

Minimally invasive direct coronary artery bypass procedures are low-risk surgical procedures. If hybrid procedures have been planned, completion of revascularization should be a major goal.

Minimally invasive surgery or stenting for left anterior descending artery disease - meta-analysis

Minimally invasive direct coronary artery bypass (MIDCAB) surgery and percutaneous coronary intervention (PCI) are both well-established minimally invasive revascularization strategies in patients with proximal left anterior descending (LAD) lesions. We aimed to evaluate the 20-years' experience by performing a systematic review and meta-analysis comparing MIDCAB versus PCI in adults with proximal LAD disease. We searched MEDLINE, EMBASE and Cochrane on October 1st, 2021 for articles published in the year 2000 or later. The primary outcome was all-cause mortality. Secondary outcomes included cardiac mortality, repeat target vessel revascularization (rTVR), myocardial infarction (MI), and cerebrovascular accident (CVA). Outcomes were analysed at short-term, mid-term, and long-term follow-up. Random effects meta-analyses were performed. Events were compared using risk ratios (RR) with 95% confidence intervals (CI). Our search yielded 17 studies pooling 3847 patients. At short-term follow-up, cardiac mortality was higher with MIDCAB than with PCI (RR 7.30, 95% CI: 1.38 to 38.61). At long-term follow-up, MIDCAB showed a decrease in all-cause mortality (RR 0.66, 95% CI: 0.46 to 0.93). MIDCAB showed a decrease in rTVR at mid-term follow-up (RR 0.16, 95% CI: 0.11 to 0.23) and at long-term follow-up (RR 0.25, 95% CI: 0.17 to 0.38). MI and CVA comparisons were not significant. In conclusion, in patients with proximal LAD lesions, MIDCAB showed a higher short-term mortality in the RCTs, but the cohort studies suggested a lower all-cause mortality at long-term follow-up. We confirm a decreased rTVR at mid-term follow-up in the RCTs and long-term follow-up in the cohort studies.

Advances in revascularization of the left coronary artery

Ischaemic heart disease is the most common cardiovascular disease worldwide, and it contributes to a significant source of morbidity and mortality internationally. It can be asymptomatic for many years and present suddenly with acute coronary syndrome or can be progressive with angina and eventual acute myocardial infarction. Diseases of the left coronary system can be drastic and fatal if not managed correctly. With ongoing increase in the practice of percutaneous intervention; patient demographics for conventional coronary artery bypass grafting surgery have more risk factors than before. Conventional bypass surgery has also evolved to include minimally invasive and hybrid techniques. Although some evidence supports each approach, controversies remain.

Revascularization for Isolated Proximal Left Anterior Descending Artery Disease

BACKGROUND

Most studies of patients with isolated proximal left anterior descending (PLAD) coronary artery disease do not include all 3 procedural options: percutaneous coronary intervention (PCI), conventional coronary artery bypass graft (CABG) surgery, or minimally invasive CABG.

METHODS

New York's cardiac registries were used to identify patients who underwent revascularization for isolated PLAD disease between January 1, 2010, and November 30, 2016, in New York State. After exclusions, 14,327 patients, of whom 13,115 received PCI, 1001 of whom underwent CABG surgery, and 211 of whom underwent minimally invasive CABG were monitored through the end of 2017 to compare outcomes. Registry data were matched to vital statistics data to obtain deaths occurring after discharge and matched to claims data to obtain subsequent admissions for myocardial infarction and stroke.

RESULTS

There were no significant differences in mortality or in mortality/myocardial infarction/stroke after 7 years (with median follow-up times in excess of 4 years) among the 3 procedures after adjusting for differences in patient risk factors. However, conventional CABG surgery was associated with a lower subsequent revascularization rate than PCI (adjusted hazard ratio, 0.45; 95% confidence interval, 0.35-0.58) and minimally invasive CABG surgery (adjusted hazard ratio, 0.46; 95% confidence interval, 0.32-0.66).

CONCLUSIONS

Among patients with isolated PLAD disease undergoing any of 3 revascularization options (PCI, conventional CABG surgery, or minimally invasive CABG surgery), conventional CABG surgery was associated with lower subsequent revascularization rates, but there were no differences in mortality or mortality/myocardial infarction/stroke rates.

The results of staged endovascular revascularization with use of stents with third generations of drug-eluting and biodegradable polymer in patients with acute coronary syndrome and multivessel coronary artery disease

Background. Acute coronary syndrome (ACS) is currently the leading cause of people’s death worldwide. Objective. Based on the analysis of a combined end point, MACCE, to estimate the efficacy and safety of the strategy of staged endovascular revascularization in comparison with heart bypass surgery in patients with ACS and multivessel involvement in a distant time period. Methods. We have performed an analysis of the long-term results of staged endovascular revascularization of the myocardium using 3d generation drug-eluting stents with a biodegradable polymer coating in patients with ACS and multivessel involvement, in comparison with the results of heart bypass surgery. Results. According to the non-inferiority hypothesis test, the non-inferior efficacy of staged endovascular revascularization in comparison with heart bypass surgery has not been proven, using the MACCE combined point of emerging major cardiovascular events, the frequency of repeated revascularization in the groups does not exhibit statistically significant differences. Conclusion. Heart bypass surgery is comparable to endovascular revascularization with the use of 3d generation drug-eluting stents in the frequency of repeated revascularizations.

Minimally invasive coronary artery bypass grafting

Minimally invasive cardiac surgery (MICS)-CABG is a technique that at its core has patient comfort, early return to routine activities, meeting patient expectations for less invasive options, and maintaining the highest possible standards of care and outcomes. The technique requires not only surgical dexterity but also integration of significant technological advancements in patient care. At a time when percutaneous interventions are often prescribed on the pretext of increased patient comfort and demand, minimally invasive myocardial revascularization becomes even more relevant. Minimally invasive myocardial revascularization is ever evolving and encompasses both small-incision open techniques as well as endoscopic-assisted procedures. The success of the procedure depends not only on the learning curve and familiarity with the technology but also on appropriate patient selection. Mere feasibility of the technique is not sufficient, and the results have to be comparable with the long-established techniques of conventional coronary artery bypass grafting both in terms of early morbidity and mortality as well as long-term outcomes. In this review, we discuss patient selection and technical aspects of minimally invasive coronary artery bypass grafting. We also provide an evidence-based comparison to early and long-term outcomes with conventional coronary artery bypass grafting. Finally, we review the uptake and outcomes of minimally invasive revascularization in the Indian subcontinent.

Comparison of minimally invasive direct coronary artery bypass and drug-eluting stents for management of isolated left anterior descending artery disease: a systematic review and meta-analysis of 7,710 patients

Background

In the contemporary era of drug-eluting stents (DES) the issue of optimal revascularization strategy for patients with isolated disease of the left anterior descending (LAD) artery has gained more significance. We aimed to evaluate the current best evidence on the subject by performing a systematic review and meta-analysis of the studies comparing minimally invasive direct coronary artery bypass (MIDCAB) grafting with DES in patients with isolated LAD disease.

Methods

A literature search was conducted from 1966 through March 2018 using MEDLINE, EMBASE, and other scientific databases to identify relevant articles. Analyzed outcomes included all-cause mortality, myocardial infarction (MI), major adverse cardiac and cerebrovascular events (MACCE) and target vessel revascularization (TVR). The random effects model was used to calculate the outcomes of both binary and continuous data to control any heterogeneity between the studies. Heterogeneity amongst the trials was determined by means of the Cochran Q value and quantified using the I² inconsistency test. All P values were 2-sided and a 5% level was considered significant.

Results

A total of 7,710 patients from 12 studies were identified. There was no significant difference in mortality rate [pooled odds ratio (OR) =0.92; 95% confidence interval (CI), 0.65 to 1.32; P=0.66], MI rate (pooled OR =1.13, 95% CI, 0.62 to 2.06; P=0.69) or MACCE (pooled OR =1.31; 95% CI, 0.58 to 2.95; P=0.52). However, TVR rate was significantly more for patients having percutaneous intervention with DES (pooled OR =0.27; 95% CI, 0.16 to 0.45; P<0.0001) compared to MIDCAB.

Conclusions

MIDCAB offers superior freedom from TVR with similar mortality, MI rate, and MACCE compared to percutaneous intervention with DES for revascularization in patient with isolated proximal LAD stenosis.

Minimally invasive direct coronary bypass compared with percutaneous coronary intervention for left anterior descending artery disease: a meta-analysis

Background

The clinical outcomes for left anterior descending (LAD) coronary artery lesion between minimally invasive direct coronary artery bypass (MIDCAB) and percutaneous coronary intervention (PCI) are still controversial. The objective was to compare safety and efficacy between MIDCAB and PCI for LAD.

Methods

Electronic databases and article references were systematically searched to access relevant studies. End points included mortality, myocardial infarction, target vessel revascularization (TVR), major adverse coronary events (MACE), angina recurrence, and stroke.

Results

Fourteen studies with 941 patients were finally involved in the present study. The mortality and incidence of myocardial infarction were similar in MIDCAB and PCI groups at 30 days, 6 months, and at follow-up beyond 1 year. Compared with PCI, MIDCAB decreased incidence of TVR and MACE at 6 months and beyond 1 year follow-up. MIDCAB was associated with a lower incidence of angina recurrence at 6 months compared with PCI. PCI was associated with higher risk of restenosis in target vessel. No significant difference was shown for stroke.

Conclusion

Our meta-analysis indicates that there are no significant differences in the safety between MIDCAB and PCI in patients with LAD. However MIDCAB is superior to PCI for TVR and MACE.

Relationship between left coronary artery bifurcation angle and restenosis after stenting of the proximal left anterior descending artery

INTRODUCTION

Restenosis after a percutaneous coronary intervention for proximal left anterior descending (pLAD) coronary artery disease remains a clinical challenge. However, the relationship between the left main trunk (LMT)/LAD bifurcation angle and the pLAD artery restenosis is unclear. This study examined the relationship between the LMT-LAD bifurcation angle and restenosis after stent implantation for pLAD disease.

METHODS

We analysed the data of 177 consecutive patients who underwent stent implantation for pLAD disease, followed by coronary angiography between December 2008 and September 2013. The LMT-LAD bifurcation angle was measured in the left or the right anterior oblique caudal (CAU) angiographic view.

RESULTS AND DISCUSSION

Out of 177 patients, 12 developed in-stent restenosis and 21 developed in-segment restenosis. The mean angle in patients with in-stent restenosis (52.2°±14.5°) in the left anterior oblique CAU view was significantly larger than that in patients without restenosis (32.0°±18.1°; P<0.001). The LMT-LAD angle in the right anterior oblique CAU view was significantly larger in patients with in-segment restenosis (27.3°±14.3°) than in patients without restenosis (17.5°±10.1°; P<0.001). Moreover, by multivariate analysis, the LMT-LAD angle was an independent predictor of in-stent and in-segment restenosis, after adjustment for significant confounders such as diabetes, hypertension, dyslipidaemia, final minimum lesion diameter and lesion length.

CONCLUSION

This study suggests that a wide LMT-LAD angle is a predictor of restenosis after stent implantation for pLAD artery disease.

Coronary artery bypass grafting versus drug-eluting stents in patients with severe coronary artery disease and diabetes mellitus: systematic review and meta-analysis

BACKGROUND

A comprehensive meta-analysis was performed to evaluate the comparative benefits of coronary artery bypass grafting (CABG) versus drug-eluting stents (DES) in patients with diabetes mellitus and severe coronary artery disease (CAD).

METHODS

A comprehensive literature search of PubMed, Embase, and ScienceDirect was undertaken. References cited with the papers were also checked to identify relevant articles.

RESULTS

In all, four randomized controlled trials, two prospective registries, and 11 retrospective studies were identified for review. Pooled analysis demonstrated that DES was associated with lower all-cause mortality at Day 30. However, there was no significant difference between CABG and DES in mortality at 12 months and at maximum follow-up. Furthermore, DES was associated with lower overall and major adverse cardiac and cerebrovascular events (MACCE)-free survival, as well as a higher incidence of myocardial infarction and repeat revascularization. In contrast, CABG was associated with an increased risk of stroke.

CONCLUSIONS

For patients with diabetes mellitus and severe CAD, CABG is superior to DES in that it significantly improves overall and MACCE-free survival and reduces the incidence of myocardial infarction and repeat revascularization in the long term, although it is associated with greater perioperative risk and a higher incidence of stroke. Therefore, CABG should remain the gold standard for these patients.

Percutaneous coronary invervention versus coronary artery bypass grafting: a meta-analysis

OBJECTIVE

To compare the effectiveness of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in patients with coronary artery disease.

METHODS

MEDLINE, Embase, and Cochrane Central were searched, and randomized controlled trials were included. Outcomes were assessed at maximum available follow-up.

RESULTS

This meta-analysis includes 31 trials with 15,004 patients. As regards death, more patients died after PCI compared with CABG across all types of patients (odds ratio [OR], 1.1; 95% confidence interval [CI], 1.0-1.3; P = .05) as well as in patients with multivessel disease (OR, 1.2; 95% CI, 1.0-1.4; P = .02) or diabetes (OR, 1.6; 95% CI, 1.2-2.1; P < .01). Myocardial infarction occurred as frequently after PCI (OR, 1.2; 95% CI, 0.9-1.5; P = .28). Repeat revascularization was more common after PCI (OR, 4.5; 95% CI, 3.5-5.8; P < .01), with a progressive decline in ORs from the pre-stent era (OR, 7.0; 95% CI, 5.1-9.7; P < .01), to the bare metal stent era (OR, 4.5; 95% CI, 3.6-5.5; P < .01), and to the drug-eluting stent era (OR, 2.5; 95% CI, 1.8-3.4; P < .01). Stroke was more common after CABG (OR, 0.7; 95% CI, 0.5-0.9; P = .01).

CONCLUSIONS

Compared with PCI, CABG had a lower risk of death in multivessel disease or diabetes patients eligible for either intervention, a lower risk of repeat revascularization, but a higher risk of stroke.

Treatment of left anterior descending coronary artery stenosis: stent or surgery

BACKGROUND

Drug-eluting stents have emerged as a solution to the problem of restenosis after bare-metal stent implantation, as an alternative to off-pump coronary bypass, for isolated left anterior descending coronary artery lesions at short-term follow-up. However, long-term follow-up is yet to be defined.

METHODS

From January to December 2004, 64 consecutive patients underwent myocardial revascularization: 31 by drug-eluting stents and 33 by off-pump coronary bypass. The primary endpoint was angiographic outcome, and the secondary endpoint was clinical outcome at 5 years.

RESULTS

There was no early or late mortality in either group. Hospital stay was significantly shorter in the stent group (2.5 ± 2.1 vs. 7.1 ± 4.9 days, p = 0.003). Long-term patency was higher and major adverse cardiac events (recurrence of angina and revascularization of target vessel) were encountered less frequently in the coronary bypass group, although not significantly.

CONCLUSION

The 5-year follow-up showed no significant difference between the off-pump coronary bypass and stent groups for the primary and secondary endpoints. As a significant difference between treatment options is lacking, decision-making for appropriate treatment in this group of patients requires the collaboration of cardiologists and cardiovascular surgeons and an individual approach, to achieve successful long-term outcomes.

Surgical pitfalls of minimally invasive direct coronary artery bypass procedure from the viewpoint of a surgeon in the learning curve

Introduction

Minimally invasive direct coronary artery bypass grafting (MIDCAB) offers arterial revascularization of the left anterior descending (LAD) coronary artery especially in lesions unsuitable for percutaneous coronary interventions. By avoidance of sternotomy and cardiopulmonary bypass its invasiveness is less than that of conventional bypass surgery.

Aim

We in this study discuss our surgical experience in the MIDCAB procedure.

Material and methods

Thirteen patients were operated on with the MIDCAB procedure. The inclusion criteria for MIDCAB were pure LAD disease totally occluded or severely stenotic. Patient demographics and preoperative and postoperative data were analyzed.

Results

Mean age of the patients was 60.0 ±8.6 years. Patients’ preoperative and postoperative levels of cardiac CK-MB (creatine kinase MB) were not significantly different (p = 0.993). However, cardiac troponin I (p < 0.001), hemoglobin (p < 0.001) and hematocrit (p < 0.001) were significantly different. No perioperative myocardial infarctions or cerebrovascular accidents were seen. The patients were discharged at a mean day of 4.77 with oral antiaggregant therapy. No mortality was seen in the study population.

Conclusions

Minimally invasive direct coronary artery bypass is associated with few perioperative complications. Minimally invasive direct coronary artery bypass in our experience is a very good option for single vessel LAD disease.

Review of a 13-year single-center experience with minimally invasive direct coronary artery bypass as the primary surgical treatment of coronary artery disease

BACKGROUND AND AIM OF THE STUDY

In this study, we review our experience with 1768 minimally invasive direct coronary artery bypass (MIDCAB) operations. The focus is on long-term outcome with more than 10 years of follow-up.

METHODS

All patients undergoing standard MIDCAB between 1996 and 2009 were included. For all 1768 patients, pre-, intra-, and postoperative data could be completed. Long-term follow-up information about health status, major adverse cardiac and cerebrovascular events (MACCE), and freedom from angina was collected annually via questionnaire or personal contact. Five-year follow-up is available for 1313 patients, and 10-year-follow-up is available for 748 patients. A multivariate Cox regression analysis was performed to determine risk factors for long-term outcome.

RESULTS

Mean age was 63.4 ± 10.8 years, mean ejection fraction was 60.0% ± 14.2%, and perioperative mortality risk calculated by logistic EuroSCORE was 3.8 ± 6.2%. In 31 patients (1.75%) intraoperative conversion to sternotomy was necessary. Early postoperative mortality was 0.8% (15 patients); 0.4% (7 patients) had a perioperative stroke. Seven hundred twelve patients received routine postoperative angiogram, showing 95.5% early graft patency. Short-term target vessel reintervention was needed in 59 patients (3.3%) (11 percutaneous transluminal coronary angioplasty (PTCA)/stent, 48 re-operation). Kaplan-Meyer analysis revealed a 5-year survival rate of 88.3% (95% confidence interval [CI], 86.6% to 89.9%) and a 10-year-survival rate of 76.6% (95% CI, 73.5% to 78.7%). The freedom from MACCE and angina after 5 and 10 years was 85.3% (95% CI, 83.5% to 87.1%) and 70.9% (95% CI, 68.1% to 73.7%), respectively.

CONCLUSIONS

MIDCAB is a safe operation with low postoperative mortality and morbidity. With excellent short-term and long-term results, it is a very good alternative compared to both percutaneous coronary intervention (PCI) and conventional surgery.

The role of revascularization versus medical therapy in patients with type 2 diabetes mellitus and coronary artery disease

Patients with type 2 diabetes mellitus (T2DM) are at increased risk for cardiovascular clinical events, adverse nonfatal outcomes, and death. There has been considerable improvement in the medical management of patients with T2DM in an attempt to alter the metabolic cascade that is triggered by insulin resistance. Recent trials have demonstrated that medical management of patients with diabetes mellitus and stable coronary artery disease (CAD) is equivalent to revascularization in terms of morality benefit and rates of major adverse cardiovascular events, particularly in patients who do not have extensive CAD. Nonetheless, in those diabetic patients with additional high-risk features including left main disease, reduced left ventricular ejection fraction (LVEF), severe ischemia, or acute coronary syndrome, revascularization remains the best treatment option. Although the evidence still supports coronary artery bypass grafting (CABG) as the standard of care for revascularization of diabetic patients with multivessel CAD and/or reduced LVEF, percutaneous coronary intervention (PCI) with drug-eluting stents (DES) has resulted in at least partial closure of the gap in benefit between surgery and catheter-based intervention. Ongoing trials of diabetic patients with CAD randomized to PCI or CABG will help further elucidate the role of PCI with DES as a potential revascularization option for this patient population.

Coronary artery bypass grafting without full sternotomy

Coronary artery bypass grafting is performed without full sternotomy in selected patients because it is less invasive. Left internal thoracic artery-left anterior descending artery bypass (LITA-LAD bypass) via a small left anterior thoracotomy is a well established procedure, which achieves good graft patency with low mortality and morbidity rates. Multiple revascularization is possible with a limited lateral thoracotomy or L-figure approach. Axillary-coronary bypass and right gastroepiploic artery-right coronary artery bypass (RGEA-RCA bypass) are alternative methods, especially for redo surgery, in selected patients.

Different treatment options in chronic coronary artery disease: when is it the time for medical treatment, percutaneous coronary intervention or aortocoronary bypass surgery?

BACKGROUND

3% to 4% of the population suffers from chronic coronary artery disease (CAD). Primary care physicians, internists, cardiologists, and cardiac surgeons are involved in their long-term care. This article presents a complementary care pathway that integrates two apparently competing treatment options, aortocoronary bypass surgery (ACB) and percutaneous coronary intervention (PCI). Together with lifestyle changes and medical therapy, these treatments reduce morbidity and mortality and improve quality of life.

METHODS

This article was written by cardiac surgeons and cardiologists on the basis of the current treatment guidelines for coronary artery disease, a selective review of the literature (randomized, controlled trials and registry data), and a process of interdisciplinary consensus building.

RESULTS AND CONCLUSIONS

Lifestyle changes can reduce cardiovascular risk factors, improve quality of life, and lower cardiovascular morbidity and mortality. They provide additional benefit over and above medical therapy and/or revascularization procedures and should be strongly recommended to all patients. Revascularization is not indicated for patients who are asymptomatic on medical therapy or who have only a small area of myocardial ischemia. With either PCI or ACB, the symptoms of angina pectoris can be markedly improved, or even eliminated. Both of these revascularization procedures should be accompanied by optimized medical treatment. Revascularization is indicated when the area of myocardial ischemia is large, whether or not symptomatic angina is present. ACB is the treatment of choice for 3-vessel disease and/or left main stenosis. For all other constellations of coronary findings, ACB and PCI are equally good therapeutic options. The treating physician should take the patient's expectations into account and present the short- and long-term benefits and drawbacks of each proposed treatment to the patient so that an informed decision can be made.

Novel polymeric coatings with the potential to control in-stent restenosis--an in vitro study

Restenosis following percutaneous coronary intervention (PCI) is a considerable problem in long-term performance of cardiovascular stents, with a functional endothelial cell monolayer being important in its prevention. This study evaluates the influence of polymer coatings on human aortic endothelial cells (HAEC) and coronary artery smooth muscle cells (HCASMC) in vitro, in terms of morphology, cell number, and phenotype. It was demonstrated that the polymer coatings can be tailored to enhance adhesion and growth of HAECs whilst suppressing that of HCASMCs. It is concluded that one of the polymer coatings (BTL 01015) shows potential as a stent coating to enhance re-endothelialization.

Drug eluting stents versus coronary artery bypass surgery in patients with isolated proximal lesion in left anterior descending artery suffering from chronic stable angina

OBJECTIVE

To compare the efficacy of drug eluting stents (DES) compared with bypass surgery (CABG) with left internal mammary artery (LIMA) in patients with single vessel disease suffering from chronic stable angina.

BACKGROUND

There are a limited number of studies investigating this group of patients.

METHODS

We included 257 consecutive patients with isolated lesion in the proximal segment of left anterior descending artery (LAD). All patients suffered from chronic stable angina or from stress-induced ischemia. Of 257 patients, 147 underwent DES implantation and 110 CABG with LIMA. All patients were followed-up clinically for major adverse cardiac events.

RESULTS

The baseline demographic and angiographic characteristics were similar between the two groups. In the DES group we used sirolimus-, paclitaxel-, and ABT-578-eluting stents. The mean duration of hospitalization after CABG was 7.86 +/- 3.84 days vs. 1.02 +/- 0.19 days after PCI (P < 0.01). The incidence of MACE was 2.72% in the DES and 2.72% in the surgical group during a mean follow-up period of 18.71 +/- 6.27 months for PCI and 18.70 +/- 7.31 months for CABG (P = 0.99). There was one cardiac related death in the DES group and two in the surgical group (P = 0.58). There were three reinterventions in the DES group versus none in the surgical group (P = 0.26). Recurrence of angina was observed in 4.08% of pts in the DES group versus 6.36% in the CABG group (P = 0.57).

CONCLUSIONS

The present study demonstrated that patients suffering from chronic stable angina with isolated lesion in the proximal segment of LAD have excellent long-term outcome in both surgical and DES treatment.

Catheter-based endoscopic bypass grafting: an experimental feasibility study

PURPOSE

Construction of an endoscopic catheter-guided, bonded anastomosis to facilitate total endoscopic coronary artery bypass.

DESCRIPTION

Total endoscopic coronary artery bypass of the left internal thoracic artery to the left anterior descending coronary artery was performed on the beating heart in six pigs using a telemanipulation system. An angioplasty catheter was advanced through the left internal thoracic artery to stabilize the anastomotic site. The anastomosis was created by applying glue externally to the surrounding tissue of the left internal thoracic artery and the left anterior descending coronary artery while it was kept open by an inflated angioplasty catheter.

EVALUATION

Angiography and catheter placement at the graft site was performed in 12 minutes (10 to 28 minutes). The anastomotic constructions were easily accomplished in 3.5 minutes (2 to 4.5 minutes). The adverse events that were encountered were anastomotic leakage requiring additional glue and left anterior descending artery dissection due to the guidewire. All except one animal with an open graft and anastomosis survived the procedure. Patency was 5 of 6.

CONCLUSIONS

Catheter-based endoscopic bypass grafting is feasible. The combination of robotic technology and this simple technique for anastomotic construction may facilitate beating heart total endoscopic coronary artery bypass.

Sirolimus-eluting stent implantation for treatment of proximal left anterior descending coronary artery lesions: long-term outcome and predictors of adverse cardiac events

OBJECTIVES

Acute and long-term results after sirolimus-eluting stent (SES) implantation of proximal left anterior descending coronary artery (LAD) disease were evaluated.

BACKGROUND

Although SES has been used increasingly for the treatment of LAD disease, data regarding their safety and efficacy in a real-world population are limited.

METHODS

We investigate the short- and long-term results in 966 patients who underwent SES implantation for stenosis of proximal LAD.

RESULTS

The procedural success rate was 97.6%, and procedural non-Q-wave myocardial infarction (MI) rate was 14.5%. In-hospital major complications occurred in five patients (0.5%), including three deaths and two Q-wave MIs. During follow-up (20.4 +/- 8.9 months), there were 16 deaths (1.7%; 10 cardiac, 6 noncardiac), 2 Q-wave MIs, and 22 target lesion revascularizations (2.3%). Late stent thrombosis occurred in two patients (0.2%), 14 and 23 months after the procedure. The event-free survival rates for cardiac death/Q-wave MI were 98.6% +/- 0.4% at 1 year and 97.8% +/- 0.6% at 2 years. The cumulative probabilities of survival without major adverse cardiac events (MACE) were 96.7% +/- 0.6% at 1 year and 95.4% +/- 0.8% at 2 years. In multivariate analysis, stented length (HR 1.04, 95%CI 1.01-1.07, P = 0.009) and infarct-related artery (HR 5.18, 95%CI 1.09-24.64, P = 0.039) were independently related to cardiac death/Q-wave MI. In addition, stented length (HR 1.04, 95%CI 1.02-1.06, P < 0.001) and left ventricular dysfunction (HR 2.66, 95%CI 1.07-6.63, P = 0.036) were significant independent predictors of MACE.

CONCLUSIONS

SES implantation for proximal LAD disease appears safe and effective in a real-world population, and the independent predictors of MACE included stented length and left ventricular dysfunction.

Influence of spacer length on heparin coupling efficiency and fibrinogen adsorption of modified titanium surfaces

BACKGROUND

Chemical bonding of the drug onto surfaces by means of spacer molecules is accompanied with a reduction of the biological activity of the drug due to a constricted mobility since normally only short spacer molecule like aminopropyltrimethoxysilane (APMS) are used for drug coupling. This work aimed to study covalent attachment of heparin to titanium(oxide) surfaces by varying the length of the silane coupling agent, which should affect the biological potency of the drug due to a higher mobility with longer spacer chains.

METHODS

Covalent attachment of heparin to titanium metal and TiO2 powder was carried out using the coupling agents 3-(Trimethoxysilyl)-propylamine (APMS), N- [3-(Trimethoxysilyl)propyl]ethylenediamine (Diamino-APMS) and N1- [3-(Trimethoxy-silyl)-propyl]diethylenetriamine (Triamino-APMS). The amount of bound coupling agent and heparin was quantified photometrically by the ninhydrin reaction and the tolidine-blue test. The biological potency of heparin was determined photometrically by the chromogenic substrate Chromozym TH and fibrinogen adsorption to the modified surfaces was researched using the QCM-D (Quartz Crystal Microbalance with Dissipation Monitoring) technique.

RESULTS

Zeta-potential measurements confirmed the successful coupling reaction; the potential of the unmodified anatase surface (approx. -26 mV) shifted into the positive range (> + 40 mV) after silanisation. Binding of heparin results in a strongly negatively charged surface with zeta-potentials of approx. -39 mV. The retaining biological activity of heparin was highest for the spacer molecule Triamino-APMS. QCM-D measurements showed a lower viscosity for adsorbed fibrinogen films on heparinised surfaces by means of Triamino-APMS.

CONCLUSION

The remaining activity of heparin was found to be highest for the covalent attachment with Triamino-APMS as coupling agent due to the long chain of this spacer molecule and therefore the highest mobility of the drug. Furthermore, the adsorption of fibrinogen on the differently heparinised surfaces in real time demonstrated that with longer spacer chains the DeltaD/Deltaf ratios became higher, which is also associated with better biocompatible properties of the substrates in contact with a biosystem.

A meta-analysis of randomized control trials comparing minimally invasive direct coronary bypass grafting versus percutaneous coronary intervention for stenosis of the proximal left anterior descending artery

Percutaneous intervention (PCI) and minimally invasive direct coronary bypass grafting (MIDCAB) are both well-accepted treatment options for isolated high-grade stenosis of proximal left anterior descending coronary artery. Small studies comparing the two modalities have yielded conflicting results. We performed a meta-analysis of randomized control trials to compare percutaneous intervention with minimally invasive coronary bypass grafting for isolated proximal left anterior descending artery stenosis. Five randomized trials with a total of 711 patients and average follow-up of 2.3 years were included in the analysis; 380 patients received stents and 331 underwent surgery. Only one trial used drug eluting stents. There were a small number of events overall in each trial. Difference between mortality was 12 events versus 15 between the PCI versus MIDCAB group. Similarly, the difference in myocardial infarction was 14 versus 10, and target vessel revascularization was 56 versus 19. The relative risk for stenting versus MIDCAB was 0.96 [(95% CI: 0.47, 1.99), p=0.92, I(2)=17.5%], for mortality and myocardial infarction, 0.77 [(95% CI: 0.30, 2.01), p=0.60, I(2)=10.4%] for mortality and 1.81 [(95% CI: 0.80, 4.06), p=0.15, I(2)=65.9%] for the composite end point of mortality, myocardial infarction and target vessel revascularization. Excluding the trial with drug eluting stents the relative risk for the composite outcome of mortality, myocardial infarction and target vessel revascularization was significantly higher for PCI [RR=2.27 (95% CI: 1.32, 3.90), p=0.003, I(2)=18.9%]. Overall mortality and myocardial infarction rates are similar for bare metal stents versus MIDCAB, but surgery was associated with significantly lower rates of repeat revascularization. The number of randomized patients and events were small. The effect of drug eluting stents might close the gap of repeat revascularization compared to MIDCAB for this disease.

Comparison of outcomes of percutaneous coronary intervention on proximal versus non-proximal left anterior descending coronary artery, proximal left circumflex, and proximal right coronary artery: a cross-sectional study

Background

Previous studies have shown that lesions in proximal left anterior descending coronary artery (LAD) may develop more restenosis after balloon angioplasty than lesions in other coronary segments. However, stenting seems to have reduced this gap. In this study, we compared outcomes of percutaneous coronary intervention (PCI) on proximal LAD versus proximal left circumflex (LCX) or right coronary artery (RCA) and proximal versus non-proximal LAD.

Methods

From 1737 patients undergoing PCI between March 2004 and 2005, those with cardiogenic shock, primary PCI, total occlusions, and multivessel or multi-lesion PCI were excluded. Baseline characteristics and in-hospital outcomes were compared in 408 patients with PCI on proximal LAD versus 133 patients with PCI on proximal LCX/RCA (study I) and 244 patients with PCI on non-proximal LAD (study II). From our study populations, 449 patients in study I and 549 patients in study II participated in complete follow-up programs, and long-term PCI outcomes were compared within these groups. The statistical methods included Chi-square or Fisher's exact test, student's t-test, stratification methods, multivariate logistic regression and Cox proportional hazards model.

Results

In the proximal LAD vs. proximal LCX/RCA groups, smoking and multivessel disease were less frequent and drug-eluting stents were used more often (p = 0.01, p < 0.001, and p < 0.001, respectively). Patients had longer and smaller-diameter stents (p = 0.009, p < 0.001, respectively). In the proximal vs. non-proximal LAD groups, multivessel disease was less frequent (p = 0.05). Patients had larger reference vessel diameters (p < 0.001) and were more frequently treated with stents, especially direct stenting technique (p < 0.001). Angiographic success rate was higher in the proximal LAD versus proximal LCX/RCA and non-proximal LAD groups (p = 0.004 and p = 0.05, respectively). In long-term follow-up, major adverse cardiac events showed no difference. After statistical adjustment for significant demographic, angiographic or procedural characteristics, long-term PCI outcomes were still similar in the proximal LAD versus proximal LCX/RCA and non-proximal LAD groups.

Conclusion

Despite the known worse prognosis of proximal LAD lesions, in the era of stenting, our long-term outcomes were similar in patients with PCI on proximal LAD versus proximal LCX/RCA and non-proximal LAD. Furthermore, we had better angiographic success rates in patients with PCI on proximal LAD.

Does off-pump or minimally invasive coronary artery bypass reduce mortality, morbidity, and resource utilization when compared with percutaneous coronary intervention? A meta-analysis of randomized trials

OBJECTIVE

To determine, through meta-analysis, whether off-pump coronary artery bypass, including minimally invasive off-pump coronary artery bypass, improves short-term and midterm outcomes compared with percutaneous coronary intervention for single- or double-vessel coronary artery disease.

METHODS

The primary outcome was need for coronary reintervention at 1 to 5 years. Secondary outcomes included all major clinical morbidities and resource utilization. A comprehensive search was undertaken to identify all randomized trials of off-pump coronary artery bypass versus percutaneous coronary intervention. MEDLINE, Cochrane Library, EMBASE, and abstract databases were searched up to May 2006. All randomized trials comparing off-pump coronary artery bypass (sternotomy or minimally invasive) versus percutaneous coronary intervention and reporting at least one predefined outcome were included. Odds ratios (OR, 95% confidence intervals [CI]) and weighted mean differences (WMD, 95% CI) were analyzed.

RESULTS

Six trials involving 989 patients were included. Compared with percutaneous coronary intervention, off-pump coronary artery bypass decreased angina recurrence (OR 0.54, 95% CI 0.34-0.87) and need for reintervention at 1 to 5 years (OR 0.24, 95% CI 0.15-0.40). Major adverse coronary events were significantly reduced (OR 0.44, 95% CI 0.30-0.63) and event-free survival was significantly increased at 1 to 5 years (OR 2.32, 95% CI 1.62-3.32) for off-pump coronary artery bypass versus percutaneous coronary intervention. Coronary stenosis at 6 months was reduced with off-pump coronary artery bypass compared with percutaneous coronary intervention (OR 0.31, 95% CI 0.18-0.55). Hospital stay was significantly increased with off-pump coronary artery bypass versus percutaneous coronary intervention (WMD 4.03, 95% CI 2.37-5.70). Quality of life favored off-pump coronary artery bypass in some domains but was reported in few studies. Death, myocardial infarction, and stroke did not significantly differ.

CONCLUSIONS

In single- or double-vessel disease, off-pump coronary artery bypass improved short-term and midterm clinical outcomes compared with percutaneous coronary intervention but was associated with an increased length of hospital stay.