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The term "angioplasty" is a [[portmanteau]] of the words "angio" (from the [[Latin language|Latin]]/[[Greek language|Greek]] word meaning vessel) and "plasticos" (Greek: fit for molding). Angioplasty has come to include all manner of [[vascular]] interventions typically performed in a minimally-invasive or "[[percutaneous]]" method.
The term "angioplasty" is a [[portmanteau]] of the words "angio" (from the [[Latin language|Latin]]/[[Greek language|Greek]] word meaning vessel) and "plasticos" (Greek: fit for molding). Angioplasty has come to include all manner of [[vascular]] interventions typically performed in a minimally-invasive or "[[percutaneous]]" method.


==Coronary angioplasty==
==Закупорка артерий angioplasty==[[Образ:Ha1.jpg|thumb|300px|A [[венечная ангиограмма]] ( Рентгеновские лучи с рентгеноконтрастным контрастом в венечных артериях), что показывает левое [[венечное кровообращение]]. Дистальный [[оставившее основную венечную артерию]] (LMCA), - в левом верхнем квадранте образа. Главные конторы банка артерии (также видимые), - [[оставившее огибающую артерию]] (LCX), какие курсы верхний-низ первоначально и затем по отношению к центру/низу, и [[оставившее предыдущим сходя]] (ПАРЕНЬ), какие курсы из левого-права в образе и затем курсы вниз середина образа, чтобы планировать под дистального LCX. ПАРЕНЬ, что обычное, имеет две больших диагональных ветки, которые возникают на центральном-верхе образа и курса по отношению к центру/праву образа.]]{{main|Percutaneous венечной пластики сосудов intervention}}Coronary, также узнанной как "[[percutaneous]] transluminal венечная пластика сосудов", сначала был разработан в 1977 [[Andreas Gruentzig]]. Процедура быстро была принята многочисленными кардиологами, и mid-1980's, много ведя медицинские центры по всему миру принимали процедуру как метод, чтобы избегать [[обходная surgery|bypass хирургия венечной артерии]]. Пластика сосудов - иногда [[Eponym|eponymously]] именуемое ''Dottering'', после Dr [[Charles Theodore Dotter]], кто, вместе с Dr Melvin P. Judkins, сначала описавшее пластику сосудов в 1964 <ref>Dotter, C. T. и M. P. Judkins, [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1422616 ''Обработка Transluminal Артеросклеротической Преграды: Описание Нового Техника и Предварительное Сообщение Своего Приложения''], Циркуляция, 1964; [http://www.circ.ahajournals.org/cgi/reprint/30/5/654 30:654-70].</ref>. Так как дипазон процедур выполненных в [[lumens]] венечных артерий расширился, имя процедуры изменилось, чтобы [[чрескожное венечное вмешательство]] (ПРОТРОМБИНОВЫЙ индекс).Иногда небольшая сетчатая трубка, или "[[stent]]", внесен кровеносный сосуд или артерия, чтобы подпирать это открывать чрескожные методы использования. Пластика сосудов с [[Stent|stenting]] - жизнеспособная альтернатива, чтобы [[обходная surgery|heart хирургия венечной артерии]].<ref>Майкл, A. D. и K. Chatterjee, [http://circ.ahajournals.org/cgi/content/full/106/23/e187 ''Пластика сосудов Против Обходной Хирургии для Болезни Венечной Артерии''], Циркуляция, 2002; 106:e187</ref> Это последовательно показано, чтобы уменьшать симптомы из-за [[болезни венечной артерии]] и, чтобы уменьшать сердечный [[ischemia]], но не показан в больших испытаниях, чтобы уменьшать выход из строя из-за болезни венечной артерии, за исключением пациентов, обращавшихся для инфаркта остро (также вызванная первичная пластика сосудов). Есть небольшое но определенное уменьшение [[mortality]] с этой формой обработки по сравнению с медицинским терапия, которое обычно состоит из администрации [[thrombolysis|thrombolytic]] медикаментов ("сгусток busting").<ref>Mercado, N, Flather, MD, Boersna, E, И al, от имени Опытных Расследователей [http://www.medscape.com/viewarticle/460976 CABG против Stenting для Болезни Multivessel: Мета-анализ ARTS-1, SoS, ERACI-2, и MASS-2], Представление в Европейском Обществе Кардиологии Конгресса 2003</ref><ref>W. D. Ткача, R. J. Simes, A. Betriu, C. L. Усмешек, F. Zijlstra, E. Garcia, L. Grinfeld, Гиббоны R. J., E. E. Ribeiro, M. A. DeWood и F. Ribichini [http://jama.highwire.org/cgi/content/abstract/278/23/2093 ''Сравнение первичной венечной пластики сосудов и внутривенной тромболитической терапия для острого инфаркта миокарда: количественный обзор''], Журнал Американской Медицинской Ассоциации 278:23, 17 Декабря, 1997.</ref>===пластика сосудов процедуры Procedure===The обычно состоит из большинство следующего шагов:#Access в [[бедренную артерию]] на ноге (или, менее обычно, в [[радиальную артерию]] or [[плечевая артерия]] в рычаге (рука)), создан устройством вызвавшим "иглу дополнительного компонента". Эта процедура часто охарактеризована [[percutaneous]] доступ access.#Once в артерию приобретен, "дополнительный компонент ножен" установлен в открытии, чтобы держать артерию открытую и управлять bleeding.#Through этих ножен, длинная, гибкая, мягкая пластическая трубка вызвавшая "катетер управления" вытолкнут. Конец катетера управления установлен в рте венечной артерии. Катетер управления также учитывает краски радиопага (обычно йод основывал), чтобы быть впрыснут в венечную артерию, чтобы состояние болезни и позиция может легко быть оценена используя рентгеновские лучи реального времени visualization.#During рентгеновское визуальное наблюдение, кардиолог оценивает размер венечной артерии и выбирается тип катетер-баллона и венечного проволочного направителя, который будет использован в течение в таком случае. [[Heparin]] ( "кровяной разбавитель" или лекарство использованные, чтобы предохранять образование сгустков), даны поддерживать венечный проволочный направитель крови flow.#The, которые - чрезвычайно тонкий провод с гибким концом radiopauqe, который вставочный в через катетер управления и в венечную артерию. Пока визуализация снова рентгеновскими лучами в реальном времени представляя себе, кардиолог ведет провод через венечную артерию на место стеноза или блокировки. Конец провода - затем пройденное через блокировку. Кардиолог регулирует перемещение и направление провода руководства осторожно манипулируя концом, который сидит за пределами пациента через скручивающий guidewire. #While, проволочный направитель поступает, он теперь действует как магистраль в стеноз. Конец пластики сосудов или катетер-баллон - дупло и - затем вставочный на обратной стороне проволочного направителя-таким образом проволочный направитель - теперь в пластики сосудов катетера. Пластика сосудов катетера осторожно вытолкнута форвард, пока спущенный баллон не будет в баллона blockage.#The - затем надутое, и это сжимает [[atheroma]]tous [[plaque]] и протягивает стену артерии на expand. #If расширяемая проводная сетчатая трубка ([[stent]]), находился в баллоне, затем стент будет имплантирован (опереженный), чтобы поддерживать новую растянутую открытую позицию артерии из внутренности.<ref>[http://www.heartsite.com/html/ptca.html PTCA или Пластика сосудов Баллона]</ref>===Coronary stenting===Traditional закупорки артерий ("чистый металл") [[stent]]s обеспечивать механический каркас, который держит стену артерии открытый, предотвращающий стеноз, или сужение, венечных артерий. PTCA С stenting показан, чтобы превосходить пластику сосудов один в терпеливом результате держа патент артерий на более длинный период времени.<ref>MM Gandhi, И KD Dawkins [http://www.bmj.com/cgi/content/full/318/7184/650/Клинический обзор DC1: стенты Intracoronary] BMJ 1999;318(7184):650 (6 Маршей)</ref>Новое [[лекарство-eluting stent]]s (ДЕЗ), - традиционные стенты, которые покрыты лекарствами, какое, когда установлено в артерии, определенных лекарствах выпуска временем. Показано, что эти типы помощи стентов предохраняют рестеноз артерии через несколько другой физиологический механизм, большинство из которого доверяется в подавление роста ткани на стенсов месте. Три лекарства, [[sirolimus]], [[everolimus]] and [[paclitaxel]], продемонстрированы безопасность и эффективность в этом приложении в управляемых клинических испытаниях стенсов устройством manufacturers. {{Fact|date=March 2007}} Тем не менее, в [[2006]] три широких Европейских испытаниях кажется, указывать, что лекарство-eluting стентов может быть подверженным в случае узнанном как "последний стенсов тромбоз", где кровяное-свертывание в стенте могут произойти один или более постов-стента лет. Пока этот случай редкий, он чрезвычайно опасный и фатальный примерно через одного-третий случаев когда тромбоз происходит. <ref>Денежный Mauri, W Hsieh, JM Massaro, KKL Ho, 0 D’Agostino, и DE Cutlip. [http://Стенсов Тромбоз content.nejm.org/cgi/reprint/NEJMoa067731.pdf в Перемешанных Клинических Испытаниях Стентов Drug-Eluting] N Engl J Мед. 2007;356:1020-9.</ref><ref>Европейское Общество Новостей Науки Кардиологии, 2007 [http://Тромбоз www.escardio.org/vpo/News/Scientific/wcc-thrombosis-drug-eluting-stents.htm является ценой за успех лекарства-eluting стентов]</ref>===Risks===Risks пластика сосудов необычные, и процедура широко практика. Венечная пластика сосудов обычно выполнена интервенционистским [[cardiologist]], терапевт со специальной подготовкой на обработке сердца, использовавшего инвазивный [[catheter]]- базирующийся procedures. {{Fact|date=March 2007}}Angioplasty стал значительно защитой годами и теперь обычно был выполнен. Хотя связано некоторым риском<ref>[[United Kingdom|UK]]'s [[NHS]] индоссировавшее совет 'Наилучших Обработок' на '[[основавшее medicine|clinical подтверждение Подтверждения]] для пациентов из [[BMJ]]' на [http://пластика сосудов www.besttreatments.co.uk/btuk/electsurgery/18627.html Закупорки артерий] и [http://www.besttreatments.co.uk/btuk/electsurgery/18627.html#What%20are%20the%20risks%? риск]</ref> эти - значительно менее чем для открытого-сердца [[обходная хирургия]] со своей результирующей посылать-оперативной болью. Тем не менее вероятность повторения ангины, и требование для регулярных процедур было более высоким с пластикой сосудов. Самое последнее испытание (ПОДВЗДОШНАЯ кость ИСКУССТВА) предложило, что ПРОТРОМБИНОВЫЙ индекс с ДЕЗ может быть высшим, по крайней мере в коротком сроке.Немного грудное неудобство случайно может быть испытано и оно - по этой причине, что пациент бодрствует в течение минимально инвазивной пластики сосудов; отчет любого признака позволяет кардиолога, чтобы брать необходимое безотлагательное действие. Кровотечение из точки вставки в пахе - общее, частично из-за использования анти-[[кровяной пластинки]] лекарства свертывания. Некоторые [[bruising]] следовательно должен быть ожиданн, но случайно [[hematoma]] может сформироваться. Это может задержать уплату больницы как вытеукать из артерии в гематому может продолжить (псевдоаневризма), который требует ремонт. Инфекция на месте прокола кожи редкая и [[dissection]] (разделение) кровеносного сосуда доступа необычное. [[Аллергическая реакция]] в использованную краску контраста возможная но уменьшена новыми агентами. Ухудшение почечной функции может произойти на пациентах с пре- существующей почечной болезнью, но почечной недостаточностью, требующими, чтобы диализ был редким. Сосудистые осложнения доступа - менее общие и менее серьезные когда процедура выполнена через радиальную артерию.В давнем сроке, наиболее общий риск - стента [[restenosis]], как обсуждено выше. Это уменьшается значительно с использованием новых стентов покрытых определенными лекарствами (лекарство-eluting стентов). Наиболее серьезный риск является редкой провокацией (3%) инфаркта в течение или вскоре после процедуры; это может потребовать непредвиденную открытую сердечную хирургию. Пластика сосудов вскоре после [[инфаркта миокарда]] имеет риск вызывать [[stroke]] 1 в 1000, которое - менее чем 1 в 100 риске столкнувшихся тем получающим тромболитическим лечением лекарственными средствами. Совокупный риск смерти с пластикой сосудов - приблизительно 1%, но основная строгость заболевания сердца, пригодность пациента и присутствия другой болезни влияют на каждый individual’s риск. Следовательно для с сравнительно незначительный заболевание сердца, сохранившее хорошую сердечную функцию, разумный уровень пригодности и отсутствия других болезней, риск будет значительно меньше.Когда неудачи PTCA происходят, они часто обратиться используя обходной сосудистый шунт венечной артерии ([[CABG]]).
[[Image:Ha1.jpg|thumb|300px|A [[coronary angiogram]] (an X-ray with radio-opaque contrast in the coronary arteries) that shows the left [[coronary circulation]]. The distal [[left main coronary artery]] (LMCA) is in the left upper quadrant of the image. Its main branches (also visible) are the [[left circumflex artery]] (LCX), which courses top-to-bottom initially and then toward the centre/bottom, and the [[left anterior descending]] (LAD) artery, which courses from left-to-right on the image and then courses down the middle of the image to project underneath of the distal LCX. The LAD, as is usual, has two large diagonal branches, which arise at the centre-top of the image and course toward the centre/right of the image.]]
{{main|Percutaneous coronary intervention}}
Coronary angioplasty, also known as "[[percutaneous]] transluminal coronary angioplasty", was first developed in 1977 by [[Andreas Gruentzig]]. The procedure was quickly adopted by numerous cardiologists, and by the mid-1980's, many leading medical centers throughout the world were adopting the procedure as a method to avoid [[coronary artery bypass surgery|bypass surgery]].

Angioplasty is sometimes [[Eponym|eponymously]] referred to as ''Dottering'', after Dr [[Charles Theodore Dotter]], who, together with Dr Melvin P. Judkins, first described angioplasty in 1964<ref>Dotter, C. T. and M. P. Judkins, [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14226164&dopt=Abstract ''Transluminal Treatment of Arteriosclerotic Obstruction: Description of a New Technic and a Preliminary Report of Its Application''], Circulation, 1964; [http://www.circ.ahajournals.org/cgi/reprint/30/5/654 30:654-70].</ref>. As the range of procedures performed upon [[lumens]] of coronary arteries has widened, the name of the procedure has changed to [[percutaneous coronary intervention]] (PCI).

Sometimes a small mesh tube, or "[[stent]]", is introduced into the blood vessel or artery to prop it open using percutaneous methods. Angioplasty with [[Stent|stenting]] is a viable alternative to [[coronary artery bypass surgery|heart surgery]].<ref>Michaels, A. D. and K. Chatterjee, [http://circ.ahajournals.org/cgi/content/full/106/23/e187 ''Angioplasty Versus Bypass Surgery for Coronary Artery Disease''], Circulation, 2002; 106:e187</ref> It has consistently been shown to reduce symptoms due to [[coronary artery disease]] and to reduce cardiac [[ischemia]], but has not been shown in large trials to reduce mortality due to coronary artery disease, except in patients being treated for a heart attack acutely (also called primary angioplasty). There is a small but definite reduction of [[mortality]] with this form of treatment compared with medical therapy, which usually consists of the administration of [[thrombolysis|thrombolytic]] ("clot busting") medication.<ref>Mercado, N, Flather, MD, Boersna, E, et al, on Behalf of the Trial Investigators [http://www.medscape.com/viewarticle/460976 CABG vs Stenting for Multivessel Disease: a Meta-analysis of ARTS-1, SoS, ERACI-2, and MASS-2], Presentation at European Society of Cardiology Congress 2003</ref><ref>W. D. Weaver, R. J. Simes, A. Betriu, C. L. Grines, F. Zijlstra, E. Garcia, L. Grinfeld, R. J. Gibbons, E. E. Ribeiro, M. A. DeWood and F. Ribichini [http://jama.highwire.org/cgi/content/abstract/278/23/2093 ''Comparison of primary coronary angioplasty and intravenous thrombolytic therapy for acute myocardial infarction: a quantitative review''], Journal of the American Medical Association 278:23, December 17, 1997.</ref>

===Procedure===

The angioplasty procedure usually consists of most of the following steps:

#Access into the [[femoral artery]] in the leg (or, less commonly, into the [[radial artery]] or [[brachial artery]] in the arm) is created by a device called an "introducer needle". This procedure is often termed [[percutaneous]] access.
#Once access into the artery is gained, a "sheath introducer" is placed in the opening to keep the artery open and control bleeding.
#Through this sheath, a long, flexible, soft plastic tube called a "guiding catheter" is pushed. The tip of the guiding catheter is placed at the mouth of the coronary artery. The guiding catheter also allows for radiopaque dyes (usually iodine based) to be injected into the coronary artery, so that the disease state and location can be readily assessed using real time x-ray visualization.
#During the x-ray visualization, the cardiologist estimates the size of the coronary artery and selects the type of balloon catheter and coronary guidewire that will be used during the case. [[Heparin]] (a "blood thinner" or medicine used to prevent the formation of clots) is given to maintain blood flow.
#The coronary guidewire which is an extremely thin wire with a radiopauqe flexible tip that is inserted into through the guiding catheter and into the coronary artery. While visualizing again by real-time x-ray imaging, the cardiologist guides the wire through the coronary artery to the site of the stenosis or blockage. The tip of the wire is then passed across the blockage. The cardiologist controls the movement and direction of the guide wire by gently manipulating the end that sits outside the patient through twisting of the guidewire.
#While the guidewire is in place, it now acts as the pathway to the stenosis. The tip of the angioplasty or balloon catheter is hollow and is then inserted at the back of the guidewire--thus the guidewire is now inside of the angioplasty catheter. The angioplasty catheter is gently pushed forward, until the deflated balloon is inside of the blockage.
#The balloon is then inflated, and it compresses the [[atheroma]]tous [[plaque]] and stretches the artery wall to expand.
#If an expandable wire mesh tube ([[stent]]) was on the balloon, then the stent will be implanted (left behind) to support the new stretched open position of the artery from the inside.<ref>[http://www.heartsite.com/html/ptca.html PTCA or Balloon Angioplasty]</ref>

===Coronary stenting===
Traditional ("bare metal") coronary [[stent]]s provide a mechanical framework that holds the artery wall open, preventing stenosis, or narrowing, of coronary arteries. PTCA with stenting has been shown to be superior to angioplasty alone in patient outcome by keeping arteries patent for a longer period of time.<ref>MM Gandhi, and KD Dawkins [http://www.bmj.com/cgi/content/full/318/7184/650/DC1 Clinical review: Intracoronary stents] BMJ 1999;318(7184):650 (6 March)</ref>

Newer [[drug-eluting stent]]s (DES) are traditional stents that are coated with drugs, which, when placed in the artery, release certain drugs over time. It has been shown that these types of stents help prevent restenosis of the artery through several different physiological mechanism, most of which rely upon the suppression of tissue growth at the stent site. Three drugs, [[sirolimus]], [[everolimus]] and [[paclitaxel]], have been demonstrated safety and efficacy in this application in controlled clinical trials by stent device manufacturers. {{Fact|date=March 2007}} However, in [[2006]] three broad European trials seem to indicate that drug-eluting stents may be susceptible to an event known as "late stent thrombosis", where the blood-clotting inside the stent can occur one or more years post-stent. While this event is rare, it is extremely dangerous and is fatal in about one-third of cases when the thrombosis occurs. <ref>L Mauri, W Hsieh, JM Massaro, KKL Ho, R D’Agostino, and DE Cutlip. [http://content.nejm.org/cgi/reprint/NEJMoa067731.pdf Stent Thrombosis in Randomized Clinical Trials of Drug-Eluting Stents] N Engl J Med 2007;356:1020-9.</ref><ref>European Society of Cardiology Science News, 2007 [http://www.escardio.org/vpo/News/Scientific/wcc-thrombosis-drug-eluting-stents.htm Thrombosis is the price for the success of drug-eluting stents]</ref>

===Risks===

Risks of angioplasty are uncommon, and the procedure is widely practiced. Coronary angioplasty is usually performed by an interventional [[cardiologist]], a medical doctor with special training in the treatment of the heart using invasive [[catheter]]-based procedures. {{Fact|date=March 2007}}

Angioplasty has become considerably safer over the years and is now commonly performed. Although it is associated with some risks<ref>[[United Kingdom|UK]]'s [[NHS]] endorsed 'Best Treatments' advice on '[[Evidence-based medicine|clinical evidence]] for patients from the [[BMJ]]' on [http://www.besttreatments.co.uk/btuk/electsurgery/18627.html Coronary angioplasty] and its [http://www.besttreatments.co.uk/btuk/electsurgery/18627.html#What%20are%20the%20risks%20of%20coronary%20angioplasty? risks]</ref> these are considerably less than for open-heart [[bypass surgery]] with its resulting post-operative pain. However the likelihood of recurrence of angina, and requirement for repeated procedures has been higher with angioplasty. The latest trial (ARTS II) has suggested that PCI with DES may be superior, at least in the short term.

Some chest discomfort occasionally may be experienced and it is for this reason that the patient is awake during minimally invasive angioplasty; the reporting of any symptom allows the cardiologist to take necessary immediate action. Bleeding from the insertion point in the groin is common, in part due to the use of anti-[[platelet]] clotting drugs. Some [[bruising]] is therefore to be expected, but occasionally a [[hematoma]] may form. This may delay hospital discharge as flow from the artery into the hematoma may continue (pseudoaneurysm) which requires repair. Infection at the skin puncture site is rare and [[dissection]] (tearing) of the access blood vessel is uncommon. [[Allergic reaction]] to the contrast dye used is possible, but has been reduced with the newer agents. Deterioration of kidney function can occur in patients with pre-existing kidney disease, but kidney failure requiring dialysis is rare. Vascular access complications are less common and less serious when the procedure is performed via the radial artery.

In the long term, the most common risk is of the stent [[restenosis]], as discussed above. This has been reduced considerably with the use of newer stents coated with certain medicines (drug-eluting stents). The most serious risk is the rare provocation (3%) of a heart attack during or shortly after the procedure; this may require emergency open cardiac surgery. Angioplasty carried out shortly after a [[myocardial infarction]] has a risk of causing a [[stroke]] of 1 in 1000, which is less than the 1 in 100 risk encountered by those receiving thrombolytic drug therapy.

The overall risks of death with angioplasty is approximately 1%, but the underlying severity of the heart disease, fitness of the patient and presence of other illness affect each individual’s risk. Hence for those with relatively minor heart disease, preserved good cardiac function, reasonable level of fitness and absence of other illnesses, the risk will be considerably less.

When failures of PTCA occur, they are often treated using coronary artery bypass grafting ([[CABG]]).


==Peripheral angioplasty==
==Peripheral angioplasty==

Revision as of 09:50, 29 March 2007

Angioplasty is the mechanical widening of a narrowed or totally-obstructed blood vessel. These obstructions are often caused by atherosclerosis.

The term "angioplasty" is a portmanteau of the words "angio" (from the Latin/Greek word meaning vessel) and "plasticos" (Greek: fit for molding). Angioplasty has come to include all manner of vascular interventions typically performed in a minimally-invasive or "percutaneous" method.

Coronary angioplasty

A coronary angiogram (an X-ray with radio-opaque contrast in the coronary arteries) that shows the left coronary circulation. The distal left main coronary artery (LMCA) is in the left upper quadrant of the image. Its main branches (also visible) are the left circumflex artery (LCX), which courses top-to-bottom initially and then toward the centre/bottom, and the left anterior descending (LAD) artery, which courses from left-to-right on the image and then courses down the middle of the image to project underneath of the distal LCX. The LAD, as is usual, has two large diagonal branches, which arise at the centre-top of the image and course toward the centre/right of the image.
Main article: Percutaneous coronary intervention

Coronary angioplasty, also known as "percutaneous transluminal coronary angioplasty", was first developed in 1977 by Andreas Gruentzig. The procedure was quickly adopted by numerous cardiologists, and by the mid-1980's, many leading medical centers throughout the world were adopting the procedure as a method to avoid bypass surgery.

Angioplasty is sometimes eponymously referred to as Dottering, after Dr Charles Theodore Dotter, who, together with Dr Melvin P. Judkins, first described angioplasty in 1964[1]. As the range of procedures performed upon lumens of coronary arteries has widened, the name of the procedure has changed to percutaneous coronary intervention (PCI).

Sometimes a small mesh tube, or "stent", is introduced into the blood vessel or artery to prop it open using percutaneous methods. Angioplasty with stenting is a viable alternative to heart surgery.[2] It has consistently been shown to reduce symptoms due to coronary artery disease and to reduce cardiac ischemia, but has not been shown in large trials to reduce mortality due to coronary artery disease, except in patients being treated for a heart attack acutely (also called primary angioplasty). There is a small but definite reduction of mortality with this form of treatment compared with medical therapy, which usually consists of the administration of thrombolytic ("clot busting") medication.[3][4]

Procedure

The angioplasty procedure usually consists of most of the following steps:

  1. Access into the femoral artery in the leg (or, less commonly, into the radial artery or brachial artery in the arm) is created by a device called an "introducer needle". This procedure is often termed percutaneous access.
  2. Once access into the artery is gained, a "sheath introducer" is placed in the opening to keep the artery open and control bleeding.
  3. Through this sheath, a long, flexible, soft plastic tube called a "guiding catheter" is pushed. The tip of the guiding catheter is placed at the mouth of the coronary artery. The guiding catheter also allows for radiopaque dyes (usually iodine based) to be injected into the coronary artery, so that the disease state and location can be readily assessed using real time x-ray visualization.
  4. During the x-ray visualization, the cardiologist estimates the size of the coronary artery and selects the type of balloon catheter and coronary guidewire that will be used during the case. Heparin (a "blood thinner" or medicine used to prevent the formation of clots) is given to maintain blood flow.
  5. The coronary guidewire which is an extremely thin wire with a radiopauqe flexible tip that is inserted into through the guiding catheter and into the coronary artery. While visualizing again by real-time x-ray imaging, the cardiologist guides the wire through the coronary artery to the site of the stenosis or blockage. The tip of the wire is then passed across the blockage. The cardiologist controls the movement and direction of the guide wire by gently manipulating the end that sits outside the patient through twisting of the guidewire.
  6. While the guidewire is in place, it now acts as the pathway to the stenosis. The tip of the angioplasty or balloon catheter is hollow and is then inserted at the back of the guidewire--thus the guidewire is now inside of the angioplasty catheter. The angioplasty catheter is gently pushed forward, until the deflated balloon is inside of the blockage.
  7. The balloon is then inflated, and it compresses the atheromatous plaque and stretches the artery wall to expand.
  8. If an expandable wire mesh tube (stent) was on the balloon, then the stent will be implanted (left behind) to support the new stretched open position of the artery from the inside.[5]

Coronary stenting

Traditional ("bare metal") coronary stents provide a mechanical framework that holds the artery wall open, preventing stenosis, or narrowing, of coronary arteries. PTCA with stenting has been shown to be superior to angioplasty alone in patient outcome by keeping arteries patent for a longer period of time.[6]

Newer drug-eluting stents (DES) are traditional stents that are coated with drugs, which, when placed in the artery, release certain drugs over time. It has been shown that these types of stents help prevent restenosis of the artery through several different physiological mechanism, most of which rely upon the suppression of tissue growth at the stent site. Three drugs, sirolimus, everolimus and paclitaxel, have been demonstrated safety and efficacy in this application in controlled clinical trials by stent device manufacturers. [citation needed] However, in 2006 three broad European trials seem to indicate that drug-eluting stents may be susceptible to an event known as "late stent thrombosis", where the blood-clotting inside the stent can occur one or more years post-stent. While this event is rare, it is extremely dangerous and is fatal in about one-third of cases when the thrombosis occurs. [7][8]

Risks

Risks of angioplasty are uncommon, and the procedure is widely practiced. Coronary angioplasty is usually performed by an interventional cardiologist, a medical doctor with special training in the treatment of the heart using invasive catheter-based procedures. [citation needed]

Angioplasty has become considerably safer over the years and is now commonly performed. Although it is associated with some risks[9] these are considerably less than for open-heart bypass surgery with its resulting post-operative pain. However the likelihood of recurrence of angina, and requirement for repeated procedures has been higher with angioplasty. The latest trial (ARTS II) has suggested that PCI with DES may be superior, at least in the short term.

Some chest discomfort occasionally may be experienced and it is for this reason that the patient is awake during minimally invasive angioplasty; the reporting of any symptom allows the cardiologist to take necessary immediate action. Bleeding from the insertion point in the groin is common, in part due to the use of anti-platelet clotting drugs. Some bruising is therefore to be expected, but occasionally a hematoma may form. This may delay hospital discharge as flow from the artery into the hematoma may continue (pseudoaneurysm) which requires repair. Infection at the skin puncture site is rare and dissection (tearing) of the access blood vessel is uncommon. Allergic reaction to the contrast dye used is possible, but has been reduced with the newer agents. Deterioration of kidney function can occur in patients with pre-existing kidney disease, but kidney failure requiring dialysis is rare. Vascular access complications are less common and less serious when the procedure is performed via the radial artery.

In the long term, the most common risk is of the stent restenosis, as discussed above. This has been reduced considerably with the use of newer stents coated with certain medicines (drug-eluting stents). The most serious risk is the rare provocation (3%) of a heart attack during or shortly after the procedure; this may require emergency open cardiac surgery. Angioplasty carried out shortly after a myocardial infarction has a risk of causing a stroke of 1 in 1000, which is less than the 1 in 100 risk encountered by those receiving thrombolytic drug therapy.

The overall risks of death with angioplasty is approximately 1%, but the underlying severity of the heart disease, fitness of the patient and presence of other illness affect each individual’s risk. Hence for those with relatively minor heart disease, preserved good cardiac function, reasonable level of fitness and absence of other illnesses, the risk will be considerably less.

When failures of PTCA occur, they are often treated using coronary artery bypass grafting (CABG).

Peripheral angioplasty

Peripheral angioplasty refers to the use of mechanical widening in opening blood vessels other than the coronary arteries. It is often called percutaneous transluminal angioplasty or PTA for short. PTA is most commonly done to treat narrowings in the leg arteries, especially the common iliac, external iliac, superficial femoral and popliteal arteries. PTA can also be done to treat narrowings in veins.

Renal artery angioplasty

Atherosclerotic obstruction of the renal artery can be treated with angioplasty of the renal artery (percutaneous transluminal renal angioplasty, PTRA). Renal artery stenosis can lead to hypertension and loss of renal function.

Carotid angioplasty

Generally, carotid artery stenosis is treated with angioplasty and stenting for high risk patients in many hospitals. It has changed since the FDA has approved the first carotid stent system (Cordis) in July 2004 and the second (Guidant) in August 2004. The system comprises a stent along with an embolic capture device designed to reduce or trap emboli and clot debris. Angioplasty and stenting is increasingly being used to also treat carotid stenosis, with success rates similar to carotid endarterectomy surgery. Simple angioplasty without stenting is falling out of favor in this vascular bed. SAPPHIRE, a large trial comparing carotid endarterectomy and carotid stenting with the Cordis stent found stenting non-inferior to carotid endarterectomy. [10].

See also

References

  1. ^ Dotter, C. T. and M. P. Judkins, Transluminal Treatment of Arteriosclerotic Obstruction: Description of a New Technic and a Preliminary Report of Its Application, Circulation, 1964; 30:654-70.
  2. ^ Michaels, A. D. and K. Chatterjee, Angioplasty Versus Bypass Surgery for Coronary Artery Disease, Circulation, 2002; 106:e187
  3. ^ Mercado, N, Flather, MD, Boersna, E, et al, on Behalf of the Trial Investigators CABG vs Stenting for Multivessel Disease: a Meta-analysis of ARTS-1, SoS, ERACI-2, and MASS-2, Presentation at European Society of Cardiology Congress 2003
  4. ^ W. D. Weaver, R. J. Simes, A. Betriu, C. L. Grines, F. Zijlstra, E. Garcia, L. Grinfeld, R. J. Gibbons, E. E. Ribeiro, M. A. DeWood and F. Ribichini Comparison of primary coronary angioplasty and intravenous thrombolytic therapy for acute myocardial infarction: a quantitative review, Journal of the American Medical Association 278:23, December 17, 1997.
  5. ^ PTCA or Balloon Angioplasty
  6. ^ MM Gandhi, and KD Dawkins Clinical review: Intracoronary stents BMJ 1999;318(7184):650 (6 March)
  7. ^ L Mauri, W Hsieh, JM Massaro, KKL Ho, R D’Agostino, and DE Cutlip. Stent Thrombosis in Randomized Clinical Trials of Drug-Eluting Stents N Engl J Med 2007;356:1020-9.
  8. ^ European Society of Cardiology Science News, 2007 Thrombosis is the price for the success of drug-eluting stents
  9. ^ UK's NHS endorsed 'Best Treatments' advice on 'clinical evidence for patients from the BMJ' on Coronary angioplasty and its risks
  10. ^ Yadav JS, Wholey MH, Kuntz RE, Fayad P, Katzen BT, Mishkel GJ, Bajwa TK, Whitlow P, Strickman NE, Jaff MR, Popma JJ, Snead DB, Cutlip DE, Firth BG, Ouriel K. Protected carotid-artery stenting versus endarterectomy in high-risk patients. N Engl J Med 2004;351:1493-501. PMID 15470212.
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