Valdes Pedro J., Nagalli Shivaraj, Diaz Miguel A.
Palmetto General Hospital
Yuma Regional Medical Center
Calcium deposits within a coronary artery are a harbinger of previous inflammation, healing, and scarring. Significant calcification is synonymous with significant atherosclerotic coronary artery disease (CAD). Coronary calcification can be spread diffusely throughout coronary arteries, during imaging of the vessel significant calcification can encompass the vessel in a 360-degree manner. Coronary stenoses with circumferential or significant vessel calcification are rigid and frequently not dilatable with use of conventional balloon angioplasty. Often stent dilation and maximal vessel wall apposition are compromised in extensively calcified coronary lesions, stents deployed in heavily calcified vessels without atherectomy tend to thrombose, restenosis, and could cause stent fracture. Significant calcification remains a major limitation of balloon angioplasty as well as successful stent delivery to severely affected vessels. In cases with heavily calcified lesions, high-pressure, non-compliant balloon inflations may still fail to dilate adequately and prepare a heavily calcified vessel for stent delivery. Atherectomy refers to the removal of the obstructing material, and in our case this is calcium. By removing significant calcification or modifying the calcified atherosclerotic plaque vessel wall compliance in calcified or fibrotic lesions is increased, and the lumen diameter gained from using this device will be much improved as compared to the use of simple balloon angioplasty. Rotational atherectomy is one of several ways to perform atherectomy in a coronary vessel. It is the most commonly used atherectomy device and removes atheromatous plaque by differential cutting, that is removing the inelastic calcified plaque with microscopic (20 to 50 micrometers) diamond chips embedded on the surface of a rapidly rotating (150,000 to 200,000 rpm) olive-shaped burr. Such abrasion generates 2 to 5-micrometer microparticles that propagate through the coronary microcirculation and are removed by the reticuloendothelial system. The burr travels over a specialized 0.009-inch guidewire and is available in diameters ranging from 1.25 to 2.50 mm. In the setting of severe calcification, smaller burr sizes should be used initially, followed by larger burrs in 0.25 to 0.50-mm increments up to 70% of the reference vessel diameter. David Auth first investigated the possibility of using a rotational device to debulk atherosclerotic plaque in the early 1980s. Fourier et al. performed the first case of RA in human coronary arteries in 1988.
冠状动脉内的钙沉积是既往炎症、愈合和瘢痕形成的先兆。显著钙化与严重的动脉粥样硬化性冠状动脉疾病(CAD)同义。冠状动脉钙化可弥漫性分布于整个冠状动脉,在血管成像时,显著钙化可呈360度包绕血管。伴有圆周状或显著血管钙化的冠状动脉狭窄较为僵硬,使用传统球囊血管成形术往往无法扩张。在广泛钙化的冠状动脉病变中,支架扩张及血管壁的最大贴壁常常受到影响,在未进行斑块旋切术的情况下,置入严重钙化血管的支架容易发生血栓形成、再狭窄,并可能导致支架断裂。显著钙化仍然是球囊血管成形术以及成功将支架置入严重病变血管的主要限制因素。在病变严重钙化的情况下,使用高压、非顺应性球囊扩张仍可能无法充分扩张,难以使严重钙化的血管为支架置入做好准备。斑块旋切术是指去除阻塞性物质,在我们的病例中即去除钙。通过去除显著钙化或改变钙化动脉粥样硬化斑块,钙化或纤维化病变处血管壁的顺应性得以提高,与单纯使用球囊血管成形术相比,使用该装置获得的管腔直径将有显著改善。旋磨术是在冠状动脉内进行斑块旋切术的几种方法之一。它是最常用的斑块旋切装置,通过差异切割去除动脉粥样硬化斑块,即使用表面镶嵌有微小(20至50微米)金刚石颗粒的快速旋转(150,000至200,000转/分钟)橄榄形磨头去除无弹性的钙化斑块。这种磨损会产生2至5微米的微粒,这些微粒通过冠状动脉微循环传播,并被网状内皮系统清除。磨头通过一根特殊的0.009英寸导丝输送,其直径范围为1.25至2.50毫米。在严重钙化的情况下,应首先使用较小直径的磨头,随后以0.25至0.50毫米的增量逐步更换为较大直径的磨头,最大可达参考血管直径的70%。大卫·奥思在20世纪80年代初首次研究了使用旋转装置去除动脉粥样硬化斑块的可能性。1988年,傅里叶等人在人体冠状动脉中完成了首例旋磨术。