An Update on Coronary Artery Chronic Total Occlusions

Abstract

A coronary artery chronic total occlusion (CTO) represents a coronary artery that has been occluded for a long period of time, typically months. Coronary artery CTOs are common and occur in approximately one-third of patients referred for coronary angiography. Revascularization of CTO is technically challenging and has historically been associated with lower procedural success rates and higher complication rates. Technical success of CTO revascularization has significantly improved given remarkable advances in interventional cardiology over the past 3 decades. However, the decision to perform CTO revascularization remains a dilemma, given the lack of robust clinical evidence to support its use.     

慢性冠状动脉完全闭塞病变血运重建术后QTd、QTcd变化的研究

目的探讨慢性冠状动脉完全闭塞病变患者血运重建（CRY）术前、术后的QT间期离散度（QTd）及校正QT间期离散度（QTcd）的变化。方法20例慢性冠状动脉完全闭塞病变患者行经皮冠状动脉介入（PCI）治疗和24例患者行冠状动脉搭桥术（CABG），利用标准同步12导联心电图，对术前、术后1d、术后1周及术后1个月的QTd及QTcd进行测量计算。结果慢性冠状动脉完全闭塞病变患者行PCI治疗与CABG术后的QTd及QTcd较术前均显著缩短（P〈0．01），两组QTd及QTcd缩短程度及时间差异无统计学意义（P〉0．05）。结论慢性冠状动脉完全闭塞病变仍存在存活冬眠心肌或顿抑心肌。血运重建后再灌注心肌可恢复电生理功能，且两种血运重建方法术后1个月内至少在改善心肌电活动程度和时间上是一致的。     

经桡动脉介入治疗慢性完全性冠脉闭塞病变的可行性和安全性

目的 目前经桡动脉心导管检查越来越普遍,但是它应用在经皮冠脉介入(PCI)治疗慢性完全性冠脉闭塞(CTO)较少被报道.本研究考察经桡动脉(PCI)介入治疗CTO病变的可行性和安全性.方法 我们回顾性研究了我院419例从2008年2月到2010年12月因慢性完全性冠脉闭塞而进行了PCI治疗的病人.分两组,一组经桡动脉手术400例,另一组经股动脉手术19例.结果 两组基本临床特征相似.经桡动脉组比经股动脉组有更多的新病变发生率(76％vs47.37％,P=0.012),更少的术后支架内再狭窄发生率(11.75％vs36.84％,P=0.006)和使用更小的导管(P＜0.001).主要并发症的发生,如猝死、急性Q波心梗、紧急冠脉搭桥手术,两组没有显著性差异.结论 经桡动脉PCI治疗CTO病变更优于经股动脉.我们强力推荐在冠脉造影,尤其是治疗CTO时,优先选择经桡动脉.如果手术失败是因为导管小支撑不足时选择经股动脉PCI并用大号导管.     

Laser revascularization in the management of coronary artery disease

In recent years, laser therapy has been evaluated for the treatment of patients with angina who have coronary artery disease which is not amenable to conventional revascularization techniques. The results of transmyocardial revascularization and percutaneous myocardial revascularization are reviewed.     

Screening and management of coronary artery disease in diabetic patients

Diabetes represents as independent risk factor for coronary artery disease (CAD) and the prognosis in term of survival rates is worse for diabetic patients who have CAD with report to those with CAD but no diabetes. The coronary artery disease in diabetes has specificities and, in particular, more extensive atherosclerosis. Diabetic patients are also more frequently asymptomatic. Due to the extreme complexity of ischemic vascular disease in patients with diabetes, an optimal therapeutic strategy is based on the correction of elevated blood glucose and lipid levels, of blood pressure, of platelet and coagulation abnormalities. Diabetic patients benefit from secondary prevention by drug therapy(aspirin, lipid lowering with statines, beta blocker and ACE inhibitors) to the same extent as, or more than, non-diabetic patients. Both percutaneous and surgical myocardial revascularization have been proved equally effective for CAD treatment in diabetes. A recent randomized trial has shown a significantly improved outcome after surgical revascularization. But, the effects of drug-eluting stents, which dramatically decrease the incidence of re-stenosis, seem promising.     

Therapeutic angiogenesis as a new experimental treatment for vascular disease

Currently, our treatment modalities for patients with severe coronary artery disease consist of combinations of medication, percutaneous transluminal coronary angioplasty (PTCA) and coronary revascularization operations. Still, the number of patients who cannot be treated adequately in these ways is growing. In recent years progress has been made in the field of angiogenesis: the process of the development of new capillaries. It is now known that blood vessel growth is an essential phenomenon in a range of disease. It is possible to inhibit or stimulate this process, offering hope for new treatments in a wide array of diseases. Stimulation of angiogenesis has already been successful in animal models of chronic peripheral and myocardial ischaemia. Results of experimental treatments of coronary patients have been reported since 1998. 'Therapeutic angiogenesis' may evolve as our fourth treatment modality for the treatment of coronary artery insufficiency.     

冠状动脉旁路移植术中旁路血管的选用及维护

目的 总结冠状动脉旁路移植术中正确选取和维护旁路血管的经验。以防止旁路血管的阻塞,保证手术的成功。方法 采用不接触取血管技术制取旁路血管材料,术后积极抗凝同时维持正常血压和血糖,结果 15例冠心病患者术后循环稳定。未发生围术期心肌梗死,心绞痛症状消失。心功能得到改善。结论 术中采用不接触取血管技术,操作仔细,轻柔,术后积极抗凝是防止旁路血管阻塞以及冠状动脉旁路移植术成功的重要因素。     

Coronary transluminal angioplasty

Obstructive coronary artery disease is widespread, fatal, and difficult to treat. Up to now, treatment has hinged on medical or surgical treatment. Transluminal angioplasty of the coronary arteries has been introduced as a simple method of relieving coronary artery obstruction with a high initial success rate and a short period of hospitalization.     

老年冠心病患者药物洗脱支架置入术后5年随访研究

目的探讨经皮冠状动脉介入术（PCI）置入雷帕霉素洗脱支架（DES）治疗高龄冠心病患者的远期疗效。方法单中心回顾性连续入选2004年1月～2006年1月在住院期间成功置入DES的102例老年冠心病患者进行随访调查,按年龄分为80～89岁组（52例）,60～79岁组（50例）。随访5年,随访包括心绞痛复发、死亡、心肌梗死、卒中和再次血运重建的主要不良心脑血管事件。结果两组PCI术成功率均为100%。随访率100%,随访5年,80～89岁组与60～79岁组术后并发症发生率（6.0%vs7.6%）、卒中发生率（3.8%vs2.0%）、心源性病死率（0%vs0%）差异无统计学意义（均P〉0.05）。80～89岁组再次血运重建率（9.6%vs24.0%）、心绞痛复发率（13.5%vs30.0%）低于60~79岁组;全因病死率（7.6%vs2.0%）高于60～79岁组。结论年龄因素对DES的疗效及安全性无明显影响,年龄〉80岁患者选择性DES安全,成功率高,远期疗效尚好。     

Addressing the inverse care law in cardiac services

BACKGROUND: Wide variation in rates of angiography and revascularization exist that are not explained by the level of need for these services. The National Service Framework for Coronary Heart Disease has set out a number of standards with the aim of increasing the number of revascularizations and reducing inequalities in access to care. In this study we aimed to investigate inequity in angiography and revascularization rates between the four Primary Care Group (PCG) areas in Camden and Islington Health Authority and to put in place measures to address the problems identified. METHODS: Routinely available data were collected on all residents within Camden and Islington Health Authority undergoing angiography, angioplasty (PTCA) or coronary artery bypass grafting (CABG) between 1997 and 2001. These were used to calculate intervention rates per million population for each of the three procedures within each PCG. Semi-structured interviews were carried out with a sample of clinicians to explore their views on the provision of revascularization services within the Health Authority. RESULTS: Angiography and revascularization rates varied widely between the four PCGs. In 2001 there was a two-fold difference for angiography and CABG and a 3.5-fold difference for PTCA. The variations were not explained by a measure of the level of need for these services. The highest rates were in the area with the lowest standardized mortality ratio for coronary heart disease. The interviews identified a number of possible explanations for the variations that related to differences in clinical behaviour atthe consultant level and barriers in access to interventional cardiology and cardiac services. Following this research, a further interventional cardiologist appointment is planned, joint protocols of care are being established and barriers to access are being addressed. CONCLUSIONS: The new strategic health authorities should make it a priority to assess inequity in the provision of services within their areas, investigate the possible causes and support the primary care trusts to implement plans to address them.     

Drug-eluting stent: a review and update

The development of stent has been a major advance in the treatment of obstructive coronary artery disease since the introduction of balloon angioplasty. However, neointimal hyperplasia occurring within the stent leading to in-stent restenosis is a main obstacle in the long-term success of percutaneous coronary intervention (PCI). The recent introduction of drug-eluting stents (DES) contributes a major breakthrough to interventional cardiology. Many large randomized clinical trials using DES have shown a remarkable reduction in angiographic restenosis and target vessel revascularization when compared with bare metal stents. The results of these trials also appear to be supported by evidence from everyday practice and non-controlled clinical trials. However, the expanded applications of DES, especially in treating complex lesions such as left main trunk, bifurcation, saphenous vein graft lesions, or in-stent restenosis, are still under evaluation with ongoing studies. With the availability of different types of DES in the market, the issue of cost should not be a deterrent and DES will eventually be an economically viable option for all patients. The adoption of DES in all percutaneous coronary intervention may become a reality in the near future. In this review article, we summarize the recent development and progress of DES as well as compare and update the results of clinical trials.     

Differences in per capita rates of revascularization and in choice of revascularization procedure for eleven states

Background  

A few studies have investigated differences in elective procedure rates across small and medium sized referral regions. The purposes of this study are to investigate differences in revascularizations across 11 entire states and to investigate differences in choice of revascularization procedure (percutaneous coronary intervention (PCI) vs. coronary artery bypass graft (CABG) surgery).     

Measuring the clinical consistency of panelists' appropriateness ratings: the case of coronary artery bypass surgery

OBJECTIVE: To assess the clinical consistency of expert panelists' ratings of appropriateness for coronary artery bypass surgery. DESIGN: Quantitative analysis of panelists' ratings. PARTICIPANTS: Nine physicians (three cardiothoracic surgeons, four cardiologists, and two internists) convened by RAND to establish criteria for the appropriateness of coronary artery bypass surgery. MAIN OUTCOMES MEASURES: Percentage of indication-pairs given clinically inconsistent ratings (i.e. higher rating assigned to one member of an indication-pair when rating should have been equal or lower). RESULTS: In the final round of appropriateness ratings, among 1785 pairs of indications differing only on a single clinical factor (e.g., three-vessel vs. two-vessel stenosis), 6.6% were assigned clinically inconsistent ratings by individual panelists, but only 2.7% received inconsistent ratings from the panel as a whole (using the median panel rating as the criterion). Internists on the panel provided fewer inconsistent ratings (4.6%) than either cardiologists (7.8%) or cardiothoracic surgeons (6.3%) (p < 0.001). More inconsistencies were noted when the factor distinguishing otherwise identical indications was symptom severity (inconsistency rate, 13.2%) or intensity of medical therapy (13.2%) than when it was number of stenosed vessels (3.8%) or proximal left anterior descending (PLAD) involvement (1.9%). Contrary to expectations, panelists' inconsistency rates increased between the initial and final rounds of appropriateness ratings (from 3.9 to 6.6%, p < 0.001). Panelists' mean ratings across indications were only weakly correlated with individual inconsistency rates (r = 0.18, p = ns). CONCLUSIONS: The RAND/UCLA method for assessing the appropriateness of coronary revascularization generally produces criteria that are clinically consistent. However, research is needed to understand the sources of panelists' inconsistencies and to reduce inconsistency rates further.     

The risk of death associated with delayed coronary artery bypass surgery

Background  

The detrimental effect of delaying surgical revascularization has been estimated in randomized trials and observational studies. It has been argued that the Kaplan-Meier method used in quantifying the hazard of delayed treatment is not appropriate for summarizing the probability of competing outcomes. Therefore, we sought to improve the estimates of the risk of death associated with delayed surgical treatment of coronary artery disease.     

57例冠状动脉慢性完全闭死病变的冠状动脉介入治疗分析

目的探讨冠状动脉慢性完全闭死病变(CTO)的临床特点。方法对825例冠状动脉造影患者中的57例CTO病变患者行经皮冠状动脉介入治疗(PCI),并对其临床资料进行统计分析。结果57例患者中,单支病变11例,双支病变29例,三支病变17例。在70支病变血管中,无前向血流通过44支,少量血流通过26支;前降支病变32支,回旋支病变16支,右冠状动脉病变22支;闭死时间≤3个月41支,>3个月29支;闭死长度≤20 mm43支,>20 mm27支;闭死末端形态呈鼠尾状42支,呈刀切状28支;70支完全闭死血管成功植入支架57支,PCI成功率81.4%。结论对心肌梗死患者尤其是合并糖尿病的男性患者,早期进行冠状动脉造影,选择适当的病例及病变,对预防CTO形成及提高PCI成功率具有积极的作用。     

Long-term planning to meet UK government coronary heart disease revascularization targets.

The National Service Framework (NSF) for Coronary Heart Disease, published in the UK in 2000, gave target intervention rates of 750 procedures per million population (pmp) for both percutaneous transluminal angioplasty (PTCA) and coronary artery bypass graft (CABG). This paper describes how one Regional Office of the Department of Health, with CABG and PTCA rates of around half the NSF target levels, designed a strategy to plan rationally to meet the derived population need for these procedures. A bottom-up needs assessment model was used to predict the population need for these procedures for the Eastern Region of the UK. The Excel-based model took account of the effects of demographic change, anticipated reduction in incidence of heart disease due to primary prevention programmes and the expected improvement in cardiology and cardiac surgery technologies. The model predicted that excess procedures would be required across the region over the next 20 years. Further access study modelling was used to determine the best location for additional tertiary cardiac centres. Further, a commissioning tool was produced that could compare the predicted need, including additional procedures needed to meet waiting list targets, with capacity available from a range of providers. These tools have been used successfully in the Eastern Region to increase the regional revascularization rates from 371 pmp CABG and 322 pmp PTCA in 2000 to planned rates of 453 pmp CABG and 447 pmp PTCA in 2002/2003, to recommend the building of a new tertiary cardiac centre in Essex in the next decade and to inform the commissioning of revascularization rates in three coronary heart disease networks.     

Emerging therapies for refractory angina

In recent years, improvements in both pharmacologic and revascularization therapies have greatly increased life expectancy for patients with coronary artery disease (CAD). As patients with more extensive CAD live longer, many develop myocardial ischemia and clinical angina that is not amenable to traditional revascularization therapy. Patients with severe, symptomatic, chronic CAD have been described as having refractory angina; they have also been termed "no-option" patients. This article discusses clinical management of this unique and growing group of patients and emerging therapeutic options including pharmacologic agents, enhanced external counterpulsation therapy, therapeutic angiogenesis, neurostimulation, and transmyocardial revascularization.     

The relationship between the supply of cardiac catheterization laboratories, cardiologists and the use of invasive cardiac procedures in northern New England

OBJECTIVES: Utilization rates of coronary angiography and cardiac revascularization have been found to vary between areas. This study addresses the relationship between resource supply and procedure rates. METHODS: We compared the association of per capita catheterization laboratories, per capita cardiologists and multi-provider markets (where more than one hospital offers coronary angiography services) with the utilization rates for angiography and cardiac revascularization in northern New England, USA. Administrative data were used to capture invasive cardiac procedures. Small area analyses were used to create coronary angiography service areas. Linear regression methods were used to measure associations between the resource supply and utilization rates. RESULTS: Variation in the use of invasive cardiac procedures was strongly associated with the population-based availability of catheterization facilities and multi-provider markets and unrelated to cardiologist supply or need (as reflected in the hospitalization rates for myocardial infarction). In the multivariate model, an increase of 1 catheterization laboratory per 100,000 population was associated with an increase in the angiography rate of 1.62 per 1000 population; those service areas with multi-provider markets were associated with an additional increase in the angiography rate of 1.27 per 1000 population (R2 = 0.84, P = 0.0006). There was a moderately strong relationship between the catheterization laboratories per capita and the revascularization rates (R2 = 0.43, P = 0.029). Angiography rates were highly associated with cardiac revascularization rates: an increase in the angiography rate of 1 per 1000 population was associated with a 0.46 per 1000 increase in the cardiac revascularization rate (R2 = 0.85, P = 0.0001). CONCLUSIONS: Our work suggests that current efforts to address variation in cardiac procedures through activities such as appropriateness criteria, guidelines and utilization review are misdirected and should be redirected towards capacity, in this case the supply of catheterization facilities.     

The Management of Coronary Artery Disease in Ethiopia: Emphasis on Revascularization

Cardiovascular diseases are number one cause of death worldwide. Over half of the cardiovascular diseases, 51%, are due to coronary artery disease. Coronary artery disease is a pathological process characterized by atherosclerotic plaque accumulation in the epicardial coronary arteries. Rupture of the fibrous cap of the plaque causes the majority of the deaths due to myocardial infarction. Angina pectoris is a discomfort in the chest or adjacent areas caused by myocardial ischemia usually precipitated by exertion. In acute coronary syndrome, the chest discomfort is either of low threshold or appears at rest and when it evolves on the background of established angina pectoris, the discomfort becomes more frequent and prolonged. Exercise electrocardiography which has been the most frequently used non-invasive test to diagnose obstructive coronary artery disease is currently shown to have inferior diagnostic performance compared with diagnostic imaging tests. The pivotal tests in patients presenting with clinical features of acute coronary syndrome are electrocardiography and determination of serum troponin I and/or T. Revascularization is the mainstay of treatment in patients with acute coronary syndrome. In chronic coronary syndrome, on top of optimal medical treatment, revascularization reduces mortality in:- 1) left main stenosis, 2) three-vessel coronary artery disease, particularly with ejection fraction of less than 40%, 3) two vessel disease with more than 75% stenosis of the proximal left anterior descending coronary artery disease.     

早期应用低分子肝素对急性心肌梗死患者溶栓疗效的影响

目的探讨对急性心肌梗死患者早期应用低分子肝素的治疗效果。方法将120例急性心肌梗死患者随机分为对照组与观察组各60例,观察组于人院后溶栓治疗前30～60min予低分子肝素5000IU腹壁皮下注射,对照组于溶栓治疗开始后12h给予低分子肝索5000IU腹壁皮下注射,对比两组再通及副反应情况。结果观察组53例再通,再通率88．3％,对照组41例再通,再通率68．3％,两组比较差异有统计学意义（P〈0．01）,观察组再通时间为（1．3±0．6）h,对照组为（1．9±0．4）h,两组比较差异有统计学意义（P〈0．01）;两组出血情况比较差异无统计学意义（P〉0．05）。结论溶栓治疗前早期应用低分子肝素对于提高急性心肌梗死患者血管再通率、缩短再通时间有积极意义,且疗效肯定,安全可靠。