血管内反推力牵引术拔除感染性起搏电极导管

应用血管内反推力牵引术，经上腔静脉途径对９例病人的１４根感染性起搏电极导管进行拔除。１０根（７１．４％）电极导管被完全拔除，不完全拔除２根（１４．３％）。拔除失败的２根（１例）起搏电极导管经外科开胸术取出。平均随访９个月，感染被控制。提示血管内反推力牵引术是拔除感染性起搏电极导管和治疗起搏器植入术后顽固性感染的有效方法。     

Effect of Hypertension on Coronary Remodeling Patterns in Angiographically Normal or Minimally Atherosclerotic Coronary Arteries: An Intravascular Ultrasound Study

Whether there is any particular role of hypertension in remodeling process has not been completely understood yet. The aim of this study was to assess the association between hypertension and remodeling patterns in normal or minimally atherosclerotic coronary arteries. Seventy-nine patients who were free of significant coronary atherosclerosis were divided into two groups according to the absence (n = 39) or presence (n = 40) of hypertension; and standard intravascular ultrasound examination was performed in 145 segments. To determine the remodeling pattern in early atherosclerotic process, patients were also analyzed according to the level of plaque burden at the lesion site after the analysis of remodeling patterns. Positive remodeling was more prevalent in the hypertensive group (52.5% vs. 12.8%; P < .001) whereas negative remodeling was more common in diabetic patients (53.6% vs. 27.4%; P = .03). Mean remodeling index was 1.04 for hypertensives and 0.96 for normotensives (P = .03). There were no correlations between remodeling patterns and other risk factors such as age, family history, and hypercholesterolemia. Early atherosclerotic lesions (<30%) exhibited more negative remodeling characteristics while intermediate pattern was observed more frequently in patients with high plaque burden (P = .006 and .02, respectively). Positive remodeling showed no association in this context (P = .07). This study demonstrated that minimal atherosclerotic lesions in hypertensives had a tendency for compensatory arterial enlargement. Positive remodeling may result from local adaptive processes within vessel wall or hemodynamic effects of blood pressure itself.     

冠状动脉血栓机化病变——“藕孔状”或“蜂窝状”表现的影像特点及介入治疗

目的　探讨冠状动脉血栓呈“蜂窝状”或“藕孔状”机化患者的临床表现与冠状动脉造影表现的特点、介入治疗的方法与作用。方法　回顾性分析10例冠状动脉造影呈现“蜂窝状”或“藕孔状”征象的血栓机化病变并进行了介入治疗的病例。结果　10例患者中7例有明确的该类病变冠状动脉支配区域的心肌梗死病史,心肌梗死的发病时间均在1个月以上（1月～20年）;3例无明确的心肌梗死病史。“蜂窝状”或“藕孔状”病变发生于右冠状动脉7例（7/10,70.0%）,前降支3例（3/10,30.0%）。10例中8例有心肌缺血依据的患者进行了介入治疗,成功7例（成功率87.5%）。7例介入治疗成功的患者,最终通过的导丝依次是Runthrough（3例）,Fielder　XT（2例）,Fielder（1例）,Pilot　150（1例）。结论　冠状动脉内呈“蜂窝状”或“藕孔状”表现的血栓机化病变多发生于右冠状动脉。其介入治疗主要依靠导丝采用滑（sliding）的技术通过病变中的微孔道,应首选亲水导丝。     

血管内支架在主动脉及外周动脉狭窄梗阻性病变中的应用

目的     

Catheter Selection for Coronary Angiography and Intervention in Anomalous Right Coronary Arteries

Background: An anomalous origin of the right coronary artery (ARCA) from the left sinus of Valsalva (LSOV) has been reported in 6–27% of patients with coronary anomalies. The unusual location and course of this anomaly poses a technical challenge for the interventionalist. Appropriate guiding catheter selection is critical to ensure successful angiography and percutaneous intervention (PCI). We report our experience in 24 patients with an anomalous RCA originating from the LSOV .
Methods: Twenty-four angiograms of ARCA-LSOV were reviewed by two independent interventionalists with attention to the origin and take off of the RCA within the aortic root. The origin was adjudicated with a scheme based on anatomical landmarks as described—A: origin from the aorta above the sinotubular plane; B: origin just below the ostium of the left coronary artery (LCA); C: origin below the sinotubular plane between the midline and the LCA; D: origin along the midline .
Results: The distribution of various takeoffs of the RCA was as follows: For type A (N = 4) the FL3.0 and FCL3.0 catheters were successful in three and one cases, respectively. For type B (N = 5) the FCL3.0 or 3.5 was successful in four out of the five cases. For type C (N = 9) the VL catheter was successful in eight (VL3.5 = 5:VL 3.0 = 3) cases. The AL catheter was successful in five cases of type D (N = 6) RCAs (AL1 = 3:AL2 = 1:AL3 = 1) .
Conclusions: The classification method and catheter selection provide a useful framework to successfully engage ARCA-LSOV and may reduce contrast and radiation exposure .     

Stent Fracture in the Coronary and Peripheral Arteries

Inherent risks of stenting include restenosis and thrombosis. Recently, stent fractures have been recognized as a complication that may result in thrombosis, perforation, restenosis, and migration of the stent resulting in morbidity and mortality. Stent fractures were originally seen in the superficial femoral arteries but have since then been reported in almost all vascular sites including the coronary, renal, carotid, iliac, and femoropopliteal arteries. Fractures are the result of the complex interplay between stent manufacturing, the stented segment, pulsatile and nonpulsatile biomechanical forces, and plaque morphology at a particular vascular site. The presentation of a patient with a fracture is highly variable, ranging from asymptomatic in nature, detected on routine screening without any sequelae, to sudden cardiac death related to a thrombosed coronary artery. Despite being recognized as an important complication, consensus on routine surveillance and diagnostic methods to detect fractures continues to be lacking. Fortunately, most cases are relatively benign and can be managed conservatively if detected. In the setting of recurrent symptoms, further intervention is usually sought. In review of the literature most cases are managed with placement of a stent over the fractured area, the stent‐in‐stent technique, but several other alternatives may be available. As the knowledge of the variables that make stents prone to fracture are identified, better technologies and techniques can be employed to minimize the risk of this complication. This article reviews the available literature on stent fractures and complications using data found on PubMed, MEDLINE, the Manufacturer and User Facility Device Experience (MAUDE) database, and the Cochrane databases. (J Interven Cardiol 2010;23:411–419)     

Angiographic and Histologic Course after Implantation of Balloon Expandable Intravascular Stents in Miniswine Coronary Arteries: Short- and Mid-Term Observations

Sixteen balloon expandable Medtronic Wiktor tantalum stents were implanted in the major coronary arteries of six minipigs, which were maintained on a normal diet and given 500 mg aspirin per day. Angiographic and histologic examinations were performed 6 and 26 weeks after implantation. Angiographically reviewed, stenting increased the inner diameter of the coronary arteries from 2.61 ± 0.44 to 3.02 ± 0.34 mm (n = 16, P ≤ 0.001). Six weeks later, this value was reduced from 2.98 ± 0.35 to 2.33 ± 0.46 mm (n = 9, P ≤ 0.05), and between 6 and 26 weeks, an increase from 2.17 ± 0.44 to 2.93 ± 0.40 mm occurred (n = 6, P ≤ 0.05). Histologic evaluation at 26 weeks after stent implantation revealed an increase of the cross-sectional area of the total vessel from 4.30 ± 1.09 to 5.50 ± 1.67 mm² (n = 9; P ≤ 0.01). This was due to widening of the total vessel and intimal proliferation, which amounted to 1.19 ± 0.46 mm² within the stented segment, as compared to 0.03 ± 0.03 mm² in control sections (P ≤ 0.01). The areas of free vessel lumen, media muscularis, and adventitia remained unchanged. In 15 of the 16 hislologically examined coronary arteries, the internal elastica was fractured at the site of stent implantation. Twelve stents had also penetrated through the external elastica without evidence of wall hemorrhage. Thirteen out of 16 stents were angiographically followed, of which 12 were patent at the final reangiography. In one animal, acute thrombosis of the stented vessel after guidewire induced coronary artery spasm caused chronic right heart failure due to right ventricular myocardial infarction. Sudden death occurred in another pig 2 hours after successful implantation of three grossly oversized stents (inner vessel diameter: 2.4 ± 0.2 mm, stent diameter 3.2 ± 0.5 mm). Autopsy revealed extensive dissections of the media with subsequent vessel occlusion. It is concluded that Medtronic Wiktor stents can be placed easily, even in more distal or curved coronary arteries. Despite antiaggregational medication, intimal proliferation is observed early after implantation, reaches a maximum at about 6 weeks, and is followed by a regression 26 weeks poststenting. At 26 weeks follow-up, the free vessel lumen at the stent site was not significantly reduced as compared to control segments. Proper adjustment of internal vessel diameter and stent diameter is necessary to prevent major dissections and thrombotic occlusions.     

Percutaneous Coronary Intervention for Chronic Total Occlusion in Single Coronary Arteries

We retrospectively compared the results of percutaneous coronary intervention (PCI) and optimal medical therapy (OMT) for chronic total occlusion (CTO) in single coronary arteries to determine whether outcomes depend on the artery involved.From January 2004 through November 2015, a total of 731 patients were treated at our center for CTO in the left anterior descending coronary artery (LAD) (234 patients, 32%), left circumflex coronary artery (LCx) (184, 25.2%), or right coronary artery (RCA) (313, 42.8%). We further classified patients by treatment (PCI or OMT) and compared the cumulative incidence of major adverse cardiac events (MACE) and the composite of total death or myocardial infarction, as well as change in left ventricular ejection fraction from baseline.The 5-year cumulative incidence of MACE was similar between the treatment groups regardless of target vessel. The 5-year cumulative incidence of the composite of total death or myocardial infarction was significantly lower after PCI than after OMT or failed PCI in the LCx (2.6% vs 11.5%; P=0.020; log-rank) and RCA (5.8% vs 17.2%; P=0.002) groups, but not in the LAD group. Cox proportional hazards regression analysis indicated that PCI independently predicted a lower incidence of the composite of total death or myocardial infarction in the LCx group (hazard ratio [HR]=0.184; 95% CI, 0.0035–0.972; P=0.046) and the RCA group (HR=0.316; 95% CI, 0.119–0.839; P=0.021).The artery involved does not appear to affect clinical outcomes of successful PCI for single-vessel CTO. Further investigation in a randomized clinical trial is warranted.     

冠状动脉小血管病变介入治疗进展

支架术和经皮腔内冠状动脉成形术联合应用对于直径≥3mm的病变血管可产生较为理想的再狭窄率和主要心血管事件发生率,然而对于直径< 3mm的病变血管而言,愈后不佳,因此现在小血管病变的介入治疗已成为关注的焦点。近年来除了传统的支架术外,还运用了各种新方法来治疗小血管病变,如药物涂层支架、洗脱支架、合理化支架、点支架、切割球囊成形术等。本文对上述各种方法的疗效作一综述。     

Two Challenging Translocation Procedures for Intramural Coronary Arteries in the Setting of Transposition of Great Arteries

Translocation of the coronary arteries remains a technical challenge in anatomic correction of transposition of great arteries. Myocardial ischemia related to the difficulties with coronary relocation is an important factor in perioperative and postoperative morbidity and mortality, particularly in the patients with complex coronary artery anatomy. Intramural coronary artery is a rare anatomic variety which may complicate the arterial switch operation in 2% to 4.6% of the reported cases. Even in the hands of experts, the mortality rate may be in twofold in this subset of patients compared with simple transposition of great artery procedures. In this report, 2 successful translocation techniques for intramural coronary arteries in the setting of arterial switch operation are described.