血管内超声指导下零对比剂行经皮冠状动脉介入治疗

目的评价血管内超声(IVUS)指导下零对比剂经皮冠状动脉介入治疗的可行性和安全性。方法入选2016年10月至2020年4月于大庆油田总医院和天津第四中心医院住院的8例冠心病患者中,在冠状动脉造影或前1次经皮冠状动脉介入治疗(PCI)时发生对比剂过敏,无法再次应用对比剂进行介入诊断和治疗者,在IVUS指导下零对比剂完成介入治疗。结果8例患者介入治疗术中未使用对比剂,参考前1次造影结果,零对比剂导引导管、导丝到位,在IVUS指导下完成病变评估、确定介入治疗部位、支架尺寸选择、置入支架后效果评估。未发生手术相关并发症,手术即刻成功率为100%。结论适当选择的对比剂过敏和严重肾功能不全患者可以在IVUS指导下零对比剂完成PCI。     

血管内超声在冠脉介入中的应用进展

冠脉造影是诊断及治疗冠心病最有价值的方法。由于冠状动脉解剖结构的特殊性及冠脉病变的多样性,冠脉造影检查对于冠脉病变的评估已不足以满足临床需要,随着冠脉支架植入技术的发展及成熟,随之出现支架贴壁不良及支架内血栓形成,使患者再次面临急性心血管事件风险概率增加。因此,在冠脉造影中应用血管内超声检查已成为冠脉介入手术的热点,其能充分评估冠脉管壁、管腔及病变性质,有利于病情的充分评估及支架选择、支架释放的应用。该文就血管内超声在冠脉介入手术中的临床应用进行综述。     

Role of intravascular ultrasound in patients with acute myocardial infarction undergoing percutaneous coronary intervention

Stent thrombosis and restenosis remain drawbacks of drug-eluting stents in patients with acute myocardial infarction (AMI). Intravascular ultrasound (IVUS) guidance for stent deployment helps optimize its results in stable patients. The aim of this study was to examine the utility of routine IVUS guidance in patients with AMI undergoing percutaneous coronary intervention (PCI). Employing data from Korea Acute Myocardial Infarction Registry (KAMIR), we analyzed 14,329 patients with AMI from April 2006 through September 2010. Patients with cardiogenic shock and rescue PCI after thrombolysis were excluded. Clinical outcomes of 2,127 patients who underwent IVUS-guided PCI were compared to those of 8,235 patients who did not. Mean age was 63.6 ± 13.5 years and 72.3% were men. Patients undergoing IVUS-guided PCI were younger, more often men, more hyperlipemic, and had increased body mass index and left ventricular ejection fraction. Number of treated vessels and stents used, stent length, and stent diameter were increased in the IVUS-guided group. Multivessel involvement was less frequent and American College of Cardiology/American Heart Association type C lesion was more frequent in the IVUS-guided group. Drug-eluting stents were more frequently used compared to bare-metal stents in the IVUS group. There was no significant relation of stent thrombosis between the 2 groups. Twelve-month all-cause death was lower in the IVUS group. After multivariate analysis and propensity score adjustment, IVUS guidance was not an independent predictor for 12-month all-cause death (hazard ratio 0.212, 0.026 to 1.73, p = 0.148). In conclusion, this study does not support routine use of IVUS guidance for stent deployment in patients who present with AMI and undergo PCI.     

Bivalirudin for percutaneous coronary intervention and in acute coronary syndromes

This review focuses on the use of bivalirudin as a replacement anticoagulant for heparin in patients undergoing percutaneous coronary intervention, or who are being treated for unstable angina pectoris, ST-elevation, or non-ST-elevation myocardial infarction. Potential advantages of bivalirudin include a lack of dependence on antithrombin III for anticoagulant activity, the ability to inactivate both fibrin-bound and soluble thrombin, a lack of aggregatory effects on platelets, a predictable anticoagulant response without monitoring, and a wider therapeutic window. Clinical trial results to date suggest that bivlirudin is at least as effective as heparin with superior safety due to lower bleeding rates.     

Impact of intravascular ultrasound guidance in patients with acute myocardial infarction undergoing percutaneous coronary intervention

Objectives: The aim of this study was to examine the utility of routine intravascular ultrasound (IVUS) guidance in patients with acute myocardial infarction (MI) undergoing percutaneous coronary intervention (PCI) with stent implantation. Background: Stent thrombosis (ST) is a serious complication of PCI with stent implantation for patients presenting with acute MI. Mechanical factors such as incomplete stent expansion and smaller stent diameters are known to correlate with ST and restenosis. IVUS guidance for stent deployment is reported to reduce these events in stable patients. Methods: We analyzed a cohort of 905 consecutive patients who underwent primary PCI for acute MI and were discharged alive. The clinical outcomes of 382 patients who underwent IVUS‐guided PCI were compared to those of 523 patients who did not. Patients who presented with cardiogenic shock and rescue PCI were excluded. The primary composite endpoint of death, MI, and target lesion revascularization at 1‐year follow‐up was systematically indexed and a propensity score was performed with regard to the use of IVUS‐guided PCI. Results: Patients undergoing IVUS‐guided PCI were older, more diabetic and hypertensive, but presented with less history of previous MI. The severity of coronary artery disease was balanced between both groups. The number of treated lesions and stents used was higher in the IVUS‐guided group, with a longer procedural duration. The overall rates of the composite primary outcome were similar (14.5% vs. 14.3%, P = 0.94) as were the rates of definite and probable stent thrombosis at 1 year (2.1% vs. 2.1%, P = 0.99) in the IVUS‐guided and no‐IVUS groups, respectively. After multivariate and propensity score adjustment, IVUS guidance was not an independent predictor for the primary endpoint. Conclusion: This study does not support the routine use of IVUS guidance for stent deployment in patients who present with acute MI and undergo primary PCI. © 2009 Wiley‐Liss, Inc.     

Primary percutaneous coronary intervention and intravascular ultrasound imaging for coronary thrombosis after cisplatin-based chemotherapy

Although cisplatin is indispensable for the chemotherapy treatment of many malignancies, cisplatin-associated thrombosis is attracting increasing attention. However, experience of primary percutaneous coronary intervention (PCI) and intravascular ultrasound imaging (IVUS) for coronary thrombosis, possibly due to cisplatin-based chemotherapy, has been limited. Case 1 with postoperative gastric cancer developed acute myocardial infarction (AMI) on the sixth day of the second chemotherapy course with conventional doses of cisplatin and tegafur gimeracil oteracil potassium. Emergency coronary angiography (CAG) showed a filling defect in the proximal left anterior descending coronary artery (LAD) concomitant with no reflow in the distal LAD. Case 2 with advanced lung cancer and brain metastasis suffered AMI on the fifth day of the first chemotherapy course with conventional doses of cisplatin and gemcitabine. Emergency CAG delineated a total occlusion in the proximal right coronary artery. In both cases, thrombectomy using aspiration catheter alone obtained optimal angiographic results and subsequent IVUS revealed no definite atherosclerotic plaque, while slow flow still remained even after selective intra-coronary infusion of vasodilator in the case 1. These cases suggest that primary PCI using thrombus-aspiration catheter might be safe and effective for coronary thrombosis due to cisplatin-based chemotherapy.     

Iatrogenic acute coronary dissection during coronary angioplasty for in-stent restenosis: role of intravascular ultrasound in diagnosis and treatment

We report on a case of coronary dissection resulting from a guidewire passing out of a stent during in-stent restenosis (ISR) treatment and a guidewire successfully negotiated into true lumen and an implanted stent under intravascular ultrasound guidance, resulting in optimal coronary blood flow.     

Routine intravascular ultrasound guidance of percutaneous coronary intervention: a critical reappraisal

Intravascular ultrasound (IVUS) has played an integral role in the evolution of interventional cardiology. However, routine IVUS guidance of coronary stent implantation is not supported by a critical reappraisal of the available evidence. Although there is a trend toward a benefit with respect to target lumen revascularization favoring IVUS-guided coronary stent implantation, it is likely that this effect is driven by improved outcomes in small vessels, long coronary stenoses, and possibly saphenous vein graft interventions. No consistent trend in the incidence of death or myocardial infarction is apparent. Furthermore, the safety, efficacy, and effectiveness of IVUS should be taken into account when considering the goals, risks, benefits, and alternatives to such a treatment strategy.     

Controversies of oral antiplatelet therapy in acute coronary syndromes and percutaneous coronary intervention

Platelet activation is a pivotal event in the pathophysiology of acute coronary syndromes (ACS) and percutaneous coronary intervention (PCI) and has a substantial impact on the outcomes in these settings. Aggressive implementation of antiplatelet therapy has significantly decreased adverse cardiovascular events, such as death, myocardial infarction (MI), stroke, and repeat revascularization. Although the widespread use of aspirin has contributed to this improvement, many patients continue to have a significant risk of recurrent events during the ensuing months to years. The advent of other antiplatelet agents, notably the thienopyridine clopidogrel bisulfate has heralded a new era of combined antiplatelet blockade, offering the hope of better outcomes. Recently, clinical trials have tested the use of dual oral antiplatelet blockade and have shown impressive results. Notably, the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) trial found that dual therapy with clopidogrel and aspirin in ACS reduced adverse cardiovascular events by 20% at 1 year (p < 0.001). The PCI-CURE substudy of CURE and the Clopidogrel for the Reduction of Events During Observation (CREDO) trial demonstrated that these benefits extend to patients undergoing both urgent and elective PCI. This article will explore the current role of and controversies in oral antiplatelet therapy after ACS and PCI.     

血管内超声与定量冠脉造影应用于冠脉临界病变诊治的比较

目的 研究血管内超声（intravascular ultrasound,IVUS）在优化民航飞行员冠脉临界病变诊断和治疗中的应用。 方法 通过定量冠脉造影（quantitative coronary angiography,QCA）和IVUS对120例飞行员患者165处冠脉临界病的最小管腔直径（minimal lumen diameter,MLD）、直径狭窄率（diamter stenosis,DS）与最小管腔面积（minimal lumen area,MLA）、面积狭窄率（area stenosis,AS）等参数进行对比分析;对IVUS提示管腔MLA<4 mm2飞行员患者的冠脉临界病变行支架植入术。 结果 ①同一临界病变处QCA显示的MLD,DS及MLA,AS值均小于IVUS相应的测量值,且差异有统计学意义（P<0.01）,表明IVUS对冠脉病变狭窄定量测量方面准确性更高;②IVUS提高血栓病变（15.0% vs. 2.5%,P<0.05）和心肌桥（42.5% vs. 2.5%,P<0.01）的诊断率;③与QCA相比,IVUS直接显示介入治疗中支架的贴壁情况,指导支架扩张完全。 结论 IVUS较QCA能更准确地检测冠脉临界病变范围,更灵敏地诊断血栓和心肌桥,利于全面优化临界病变的诊疗。     

Cardiac markers in the diagnosis of acute coronary syndromes

Evolution of the role of cardiac markers has ranged from the diagnosis of acute myocardial infarction in patients with nondiagnostic electrocardiograms to prognostic risk stratification and to guide therapy. The technology to provide rapid, real time measurements by immunoassay has provided the laboratory and clinician with a range of test options. The principal changes have been the use of rapid serial marker measurements of well-recognized cardiac markers, and the development of immunoassays for the cardiac structural proteins. Measurement of cardiac troponins has generated a new diagnostic paradigm in patients with suspected acute coronary syndromes. There is now a new gold standard biochemical test for myocardial infarction. A range of interventions can be guided by troponin measurement. The use of troponin measurements is central to management of patients with suspected acute coronary syndromes. Future developments in this field will focus on the role of existing and novel markers of inflammation and ischemia.     

Chest pain centers: diagnosis of acute coronary syndromes

Chest pain centers in the emergency department have generally been accepted as a safe, cost-effective, and rapid approach to the evaluation, triage, and management of patients with potential acute coronary syndromes. These centers were initially designed to enhance patient care by decreasing time to treatment for acute myocardial infarction (AMI) and rapidly identifying patients with unstable angina. They also included community outreach and educational objectives designed to reduce time from the onset of chest pain to ED presentation. In the past decade, health care financial constraints have created additional impetus to the development of chest pain centers. Cost reduction efforts have occurred to reduce hospitalizations, lengths of stay, and unnecessary treatments and procedures. Practitioners and administrators try to balance these goals with the imperative to provide high-quality patient care. Protocol-driven approaches have been developed for specific disease processes in emergency settings. The chest pain center concept is such an approach for patients with chest pain. Chest pain is the second most common ED presenting complaint and is a symptom related to the leading cause of death in the United States, coronary artery disease (CAD). One third of ED patients with chest pain will eventually have a diagnosis of acute coronary syndrome. Many patients with acute coronary syndromes have atypical presentations that are not diagnosed in the ED with the traditional diagnostic evaluation of a history, physical examination, and 12-lead ECG. If they are not admitted to the hospital for further evaluation, the diagnosis may be missed. The 2% to 5% of AMI patients who are inadvertently released home often have poor outcomes and result in a leading cause of malpractice suits in emergency medicine. More than one half of ED patients with chest pain have clinical findings after their initial evaluation consistent with acute coronary syndromes and are admitted to the hospital. Approximately one half of these patients, after evaluation in the hospital, are found not to have acute coronary syndromes. The cost for these negative inpatient cardiac evaluations has been estimated to be $6 billion in the United States each year. Today, chest pain centers serve as an integral component of many EDs. Their success and safety is the result of a focused, protocol-driven approach directed at the acute coronary syndrome continuum from unstable angina to transmural Q-wave myocardial infarction. New therapies for acute coronary syndromes make ED triage and risk stratification increasingly important. Although different chest pain center protocols have proved effective, all address the diagnosis and rapid treatment of acute myocardial necrosis, rest ischemia, and exercise-induced ischemia. Identifying patients with coronary artery disease in one of these stages in the spectrum of myocardial ischemia is the foundation for a successful chest pain center in the ED.     

Effect of different loading doses of atorvastatin on percutaneous coronary intervention for acute coronary syndromes

BACKGROUND

Percutaneous coronary intervention (PCI)-induced myocardial damage is associated with late cardiovascular events. Treatment with atorvastatin before PCI can reduce myocardial damage during the peri-PCI period.

OBJECTIVES

To compare the safety and myocardial effects of different atorvastatin loading doses and dosing frequency before PCI in non-ST segment elevation acute coronary syndrome (NSTE-ACS) patients.

METHODS

Eighty NSTE-ACS patients were randomly divided into four groups (20 patients per group). The control group was given 40 mg atorvastatin each night. The three loading dose groups were treated the same as in the control group, but were given 80 mg atorvastatin 12 h before PCI (low-load group) in combination with 40 mg atorvastatin 2 h to 4 h before PCI (mid-load group) or 60 mg atorvastatin 2 h to 4 h before PCI (high-load group). All patients underwent PCI within 48 h to 72 h of admission, and received 40 mg atorvastatin for at least one month after PCI. Changes in myocardial markers and highly sensitive C-reactive protein were analyzed. Patients were followed up for 30 days to monitor the incidence of major adverse cardiac events (MACE).

RESULTS

No deaths or revascularizations were recorded. The incidences of MACE differed significantly between the four groups (40%, 25%, 10% and 0% for the control, low-load, mid-load and high-load groups, respectively; P<0.05). The incidence of MACE and cardiac troponin I level above the normal range, and post-PCI increases in creatine kinase-MB and highly sensitive C-reactive protein were significantly higher in the control group than in the high-load group (all P<0.007). The post-PCI alanine aminotransferase levels in all four groups were significantly higher than the pre-PCI levels, but were within normal ranges. No myalgia or myasthenia was observed.

CONCLUSION

The results of the present study show that short-term atorvastatin loading before PCI was well tolerated and had beneficial myocardial effects in patients with NSTE-ACS.     

The impact of untreated coronary dissections on acute and long-term outcome after intravascular ultrasound guided PTCA.

AIM: Vessel size adapted PTCA results in the use of larger balloons with an increased incidence of severe vascular dissections. The aim of our trial was (a) to evaluate the effect of severe dissections on the acute outcome and (b) to study the natural history of dissections after 1 year. METHODS AND RESULTS: One hundred and seventy-eight patients with 195 lesions underwent vessel size adapted PTCA using intravascular ultrasound. Clinical and angiographic 1 year follow-up was obtained for all patients. Intravascular ultrasound was performed before PTCA to measure the external elastic membrane diameter at the lesion site so that the balloon size could be adopted (external elastic membrane-10%) and post-interventionally to determine the procedural success and the incidence of intracoronary dissections. Stent implantation was reduced to persistently flow limiting dissections (TIMI I, II). Dissections were detected by intravascular ultrasound in 128/195 (66%) lesions (by angiography in 111/195 [58%] lesions) and classified by intravascular ultrasound criteria into four groups: group I: no dissection (67 lesions [34%]), group II: mild dissections (21 lesions [11%]), group III: medium dissections (19 lesions [10%]) and group IV: severe dissections (88 lesions [45%]). Because of threatened vessel closure, GPIIb/IIIa antagonists were used in eight (4.5%) patients and a stent was implanted in two (1. 1%) patients. The cumulative event rate after 1 year was 12% and the global angiographic restenosis rate was 19%. The post-interventional evidence of severe dissections was associated with a decrease in clinical events during long-term follow up (group I: 13 events [19%] vs group IV: seven events [7%];P=0.03). This was also true for the occurrence of restenosis which was significantly lower in patients with severe dissections (group I: 19 [28%] lesions vs group IV:10 [11%] lesions;P=0.01). CONCLUSIONS: According to the theory of 'therapeutic dissections', our data suggest that substantial dissections following PTCA, which do not diminish antegrade blood flow, do not lead to an increase in acute or long-term events. The natural history of vessel injury seems to provide favourable wound healing without increase of restenosis. Thus, stenting for treatment of large dissections without flow limitation does not seem to be mandatory.     

Outcome of nonobstructive residual dissections detected by intravascular ultrasound following percutaneous coronary intervention

The purpose of this study was to assess the outcome of nonobstructive (or non-flow-limiting) residual dissection (RD) after percutaneous coronary intervention. Results of 124 consecutive native coronary lesions with angiographic nonobstructive RD in 97 patients (RD group) were compared with outcomes of 124 lesions without RD in 100 patients (non-RD group), whose characteristics were matched with those of the RD group. RD occurred after stent implantation (81 of 124 lesions, 65%) or balloon angioplasty (43 of 124 lesions, 35%). Angiographic types of RD were type A in 8 lesions (6%), B in 101 (82%), and C in 15 (12%). Stents were implanted in 65% of the lesions in each group. Clinical success (94% in RD group vs 95% in non-RD group, p = 0.77) and the in-hospital major adverse cardiac event rates were found to be similar in the 2 groups (6% vs 3%, respectively; p = 0.33). The late angiographic and clinical outcomes were also comparable. By intravascular ultrasound (IVUS) evaluation of the dissections in the RD group, area stenosis correlated with the incidence of in-hospital major adverse cardiac events (p = 0.023), whereas the final minimal lumen area correlated inversely with the occurrence of restenosis (p = 0.011). An area stenosis > or =58% was the best predictor for the incidence of in-hospital major adverse cardiac events (sensitivity 0.68, specificity 0.68). Most nonobstructive RDs are "favorable" and do not need stent implantation. IVUS evaluation identifies "unfavorable" nonobstructive (or non-flow-limiting) dissections that might be prone to acute occlusion. Nonobstructive dissections can be left untreated when final IVUS reveals an area stenosis of < 60% at the site of a dissection.