美国心脏病学学会（ACC）第56届科学年会已圆满结束，极大推动了心血压领域的专业发展，各界专家对近年来心血管疾病治疗及研究中出现的问题进行了深入探讨，对新近的技术及理论进行了大力推广。《国际循环》特邀与会专家，回顾会议精彩内容，展望新的学术进展，更多资讯请登陆《国际循环网》（acc2007.icirculation.com）浏览及下载。

ACC.07/i2 Summit Reenergizes Cardiovascular Medicine

James T. Dove M.D.， F.A.C.C.  President， American College of Cardiology

The American College of Cardiology (ACC) Annual Scientific Session is always a  seminal event for cardiovascular medicine. ACC.07， the 56th Annual Scientific 

 Session， proved no exception. More than 26，000 cardiovascular specialists， reporters， exhibitors， and more convened in New Orleans March 24~ 27 for this year’smeeting.

With much controversy surrounding stents and percutaneous coronary intervention， data on these topics were eagerly anticipated. The results of the Clinical Outcomes Utilizing percutaneous coronary Revascularization and Aggressive Guideline-driven drug Evaluation(COURAGE) trial， according to lead investigator William Boden， M.D.， F.A.C.C.，have “leveled the playing field” for physicians and patients considering treatment for severe but stable coronary artery disease. The trial showed that an initial strategy of optimal medical therapy (OMT) alone was similar to that for OMT plus percutaneous coronary intervention (PCI) for the occurrence of major cardiovascular events of nonfatal myocardial infarction and death. The OMT group did have significantly more angina.

In the ABSORB trial， researchers from the Thoraxcentre at the Erasmus University Hospital， Rotterdam， the Netherlands， evaluated the Bioabsorbable Everolimus-Eluting Coronary Stent System， which has a bioabsorbable stent made of polylactic acid (a polymer derived from lactic acid) coated with everolimus， an immunosuppressant used to prevent rejection. The six-month results of the trial show a low 11.5 percent restenosis rate and a 0.44 mm in-stent late loss of lumen area. 

The ACC.07/i2 Summit 2007 Joint Symposium: “Drug-Eluting Stent Safety — Hype or Reality?” focused on reports published regarding the short and long term risks and benefits of DES and BMS.

Two state-of-the-art lectures on complex and multivessel revascularization turned into a lively point-counterpoint session during the State-of-the-Art Lecture II. Eberhard Grube， M.D.， F.A.C.C.， presented the interventional state-of-the-art viewpoint on multivessel revascularization， while David Taggart， M.D.， gave the surgical viewpoint. Dr. Grube said there may not be evidence yet that PCI leads to better outcomes compared with CABG in complex and multivessel lesions， but efficacy and safety are virtually the same and the choice should be based on patient and physician preference. Dr. Taggart said there is no unbiased evidence that the two are equal.

Trials Examine Herbal Supplements， Statins， More

In other exciting developments， a series of heart failure trials reaffirmed the importance of intense outpatient management of heart failure (HF) patients. Other key trials investigated the effects of adding antioxidants and anti-inflammatory agents to optimal medical therapy in high-risk patients with recent ACS， and the effects of hawthorn extract on congestive heart failure patients receiving pharmacologic treatment. Three trials on the effects of torcetrapib on progression of atherosclerosis showed the novel drug had virtually no effect on either coronary or carotid disease， despite unparalleled improvements in LDL-C and HDL-C levels.

Patients First

Quality cardiovascular medicine is not all about the science and technology. During ACC.07， I was honored to be installed as president of the ACC. On that humbling occasion， I encouraged my colleagues to rely on the evidence and the established guidelines， but above all， to treat every patient as though they were treating a member of their family. We have an obligation beyond ordering tests and procedures to help the patient and family deal with the decisions and stress that a diagnosis of cardiovascular disease creates.

I emphasized to my colleagues in the United States the need for ACC to take an active role in the Health Care reform debate to promote the development of patient-centered， appropriate， quality cardiovascular care. We must be active participants at that table to improve access to care.

Potential Therapeutic Application of Injectable Biomaterials in Cardiac Repair

Good Samaritan Hospital， California

Myocardial infarction results in irreversible cardiac muscle cell death with subse
 quent formation of akinetic scar tissue and progressive ventricular remodeling 

 which ultimately leads to heart failure. Experimental and clinical data have demonstrated that cell transplantation therapy improves cardiac function after myocardial infarction. However， the underlying mechanism remains unclear， and the possible interpretations involve regeneration of true cardiac muscle， formation of new blood vessels， prevention of deleterious left ventricular remodeling， as well as the secretion of paracrine factors by engrafted cells. Whether prevention of deleterious left ventricular remodeling with cells is due to a passive thickening of the wall of the ventricle or requires active cell contraction was not clear. 

In order to determine whether simply thickening and toughening the thinned infarct wall might reduce the paradoxical systolic bulging and improve cardiac function， our research group injected high density collagen (65 mg/ml， obtained from INAMED Corporation， 5540 Ikwill Street， Santa Barbara， CA) or saline (100 μl) into 1-week-old myocardial infarcts in Fischer rats. The collagen implant was composed of 95% collagen I and 5% collagen III derived from bovine dermal collagen. Six weeks later， histology showed that collagen injection significantly increased scar thickness compared to the saline-treated group. Analysis of regional wall motion demonstrated that paradoxical systolic bulging was prevented in the 11 out 11 collagen treated rats. Left ventricular function assessed by left ventricular angiography was significantly improved in the collagen-treated group compared with that in the saline-treated group. This study suggested that thickening the infarct scar by collagen implantation prevented paradoxical systolic bulging of the infarcted wall and improved left ventricular function after myocardial infarction. However， we did not observe angiogenesis within the collagen implant at 6 weeks after implantation in this study.

 In contrast， Huang et al. demonstrated that implantation of fibrin， collagen I， and Matrigel， into the infarct zone yielded significantly higher levels of capillary formation compared with the saline control group at 5 weeks in a rat myocardial infarction model. We hypothesized that the density of collagen implant might affect the development of angiogenesis. In the 56th annual scientific session of American College of Cardiology， our research group presented the data regarding the influence of collagen density upon angiogenesis within myocardial infarct tissue. We injected low density collagen (100 μl， 35 mg/ml， obtained from INAMED Corporation) (n=3) or saline (100 μl， n=2) into the scar of 1-week-old myocardial infarcts in Fischer rats， the same model as used in the previous publication. Ra