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| {{Infobox medical intervention | | {{Short description|Medical treatment to restore blood flow}} |
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| '''Reperfusion therapy''' is a medical treatment to restore blood flow, either through or around, blocked arteries, typically after a heart attack ([[myocardial infarction]] (MI)). Reperfusion therapy includes [[pharmaceutical drug|drugs]] and [[surgery]]. The drugs are [[thrombolytic drug|thrombolytics]] and [[Fibrinolysis#Pharmacology|fibrinolytic]]s used in a process called [[thrombolysis]]. Surgeries performed may be [[minimally-invasive procedure|minimally-invasive]] [[Interventional radiology#Vascular|endovascular procedures]] such as a [[percutaneous coronary intervention]] (PCI), followed by a [[angioplasty|coronary angioplasty]]. The angioplasty uses the insertion of a [[balloon catheter|balloon]] to open up the artery, with the possible additional use of one or more [[stent]]s.<ref>{{cite journal|vauthors=McCoy SS, Crowson CS, Maradit-Kremers H, Therneau TM, Roger VL, Matteson EL, Gabriel SE |title=Longterm Outcomes and Treatment After Myocardial Infarction in Patients with Rheumatoid Arthritis|journal=The Journal of Rheumatology|date=May 2013|volume=40|issue=5|pages=605–10|pmid=23418388|doi=10.3899/jrheum.120941|pmc=3895921}}</ref> Other surgeries performed are the more invasive [[Vascular bypass#Cardiac bypass|bypass surgeries]] that graft arteries around blockages. | | '''Reperfusion therapy''' is a medical treatment aimed at restoring blood flow to tissue that has been deprived of oxygen and nutrients due to a blockage in the blood vessels. This therapy is crucial in the management of [[ischemic heart disease]], [[stroke]], and other conditions where blood supply is compromised. |
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| If an MI is presented with [[Electrocardiography in myocardial infarction|ECG]] evidence of an [[ST elevation]] known as [[Myocardial infarction#STEMI|STEMI]], or if a [[bundle branch block]] is similarly presented, then reperfusion therapy is necessary. In the absence of an ST elevation, a non-ST elevation MI, known as an [[myocardial infarction#NSTEMI|NSTEMI]], or an [[unstable angina]] may be presumed (both of these are indistinguishable on initial evaluation of symptoms). ST elevations indicate a completely blocked artery needing immediate reperfusion. In NSTEMI the blood flow is present but limited by [[stenosis]]. In NSTEMI, thrombolytics must be avoided as there is no clear benefit of their use <ref>https://www.ncbi.nlm.nih.gov/pubmed?term=8149520</ref>. If the condition stays stable a [[cardiac stress test]] may be offered, and if needed subsequent [[revascularization]] will be carried out to restore a normal blood flow. If the blood flow becomes unstable an urgent angioplasty may be required. In these unstable cases the use of thrombolytics is contraindicated.<ref name="FTT_Lancet">{{cite journal | author = Fibrinolytic Therapy Trialists' (FTT) Collaborative Group | year = 1994 | title = Indications for fibrinolytic therapy in suspected acute myocardial infarction: collaborative overview of early mortality and major morbidity results from all randomised trials of more than 1000 patients. | url = | journal = Lancet | volume = 343 | issue = 8893| pages = 311–22 | doi = 10.1016/s0140-6736(94)91161-4 | pmid = 7905143 }}</ref>
| | ==Mechanism of Action== |
| | Reperfusion therapy works by reopening blocked blood vessels, thereby restoring blood flow to the affected tissue. This can be achieved through various methods, including pharmacological and mechanical interventions. The primary goal is to minimize tissue damage and preserve organ function. |
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| At least 10% of treated cases of STEMI do not develop [[necrosis]] of the [[myocardium|heart muscle]]. A successful restoration of blood flow is known as aborting the heart attack. About 25% of STEMIs can be aborted if treated within the hour of symptoms onset.<ref name=Verheught2006>{{cite journal |vauthors=Verheugt FW, Gersh BJ, Armstrong PW | year = 2006 | title = Aborted myocardial infarction: a new target for reperfusion therapy | url = | journal = Eur Heart J | volume = 27 | issue = 8| pages = 901–4 | pmid = 16543251 | doi = 10.1093/eurheartj/ehi829 }}</ref>
| | ===Pharmacological Reperfusion=== |
| | Pharmacological reperfusion involves the use of drugs to dissolve blood clots. The most common agents used are [[thrombolytics]], which include medications such as [[alteplase]], [[reteplase]], and [[tenecteplase]]. These drugs work by activating the body's fibrinolytic system to break down the fibrin in blood clots. |
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| ==Thrombolytic therapy== | | ===Mechanical Reperfusion=== |
| {{Main|Thrombolysis}}
| | Mechanical reperfusion is achieved through procedures such as [[percutaneous coronary intervention]] (PCI) and [[thrombectomy]]. PCI involves the use of a balloon catheter to open up blocked coronary arteries, often followed by the placement of a [[stent]] to keep the artery open. Thrombectomy is a procedure used to physically remove clots from blood vessels, commonly used in the treatment of [[acute ischemic stroke]]. |
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| ===Myocardial infarction=== | | ==Indications== |
| [[Thrombolysis|Thrombolytic therapy]] is indicated for the treatment of STEMI – if it can begin within 12 hours of the onset of symptoms, and the person is eligible based on exclusion criteria, and a [[angioplasty|coronary angioplasty]] is not immediately available.<ref name=Antman-2004>{{cite journal | vauthors=Antman EM, Anbe DT, Armstrong PW, Bates ER, Green LA, Hand M, Hochman JS, Krumholz HM, Kushner FG, Lamas GA, Mullany CJ, Ornato JP, Pearle DL, Sloan MA, ((Smith SC Jr)) | year=2004 | title=ACC/AHA guidelines for the management of patients with ST-elevation myocardial infarction: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Revise the 1999 Guidelines for the Management of Patients With Acute Myocardial Infarction) | journal=J Am Coll Cardiol | volume=44 | pages=671–719 | pmid=15358045 | url=http://www.acc.org/qualityandscience/clinical/guidelines/stemi/Guideline1/index.htm | issue=3 | doi=10.1016/j.jacc.2004.07.002 | url-status=dead | archiveurl=https://web.archive.org/web/20100509012940/http://www.acc.org/qualityandscience/clinical/guidelines/stemi/guideline1/index.htm | archivedate=2010-05-09 }}</ref> Thrombolysis is most effective in the first 2 hours. After 12 hours, the risk of [[intracranial hemorrhage|intracranial bleeding]] associated with thrombolytic therapy outweighs any benefit.<ref name="FTT_Lancet"/><ref name="Golden_Hour_Lancet">{{cite journal |vauthors=Boersma E, Maas AC, Deckers JW, Simoons ML | year = 1996 | title = Early thrombolytic treatment in acute myocardial infarction: reappraisal of the golden hour | journal = Lancet | volume = 348 | issue = 9030| pages = 771–5 | pmid = 8813982 | doi=10.1016/S0140-6736(96)02514-7| hdl = 1765/58599 }}</ref><ref name="LATE-1993">{{cite journal | author=LATE trial intestigatos. | title=Late Assessment of Thrombolytic Efficacy (LATE) study with alteplase 6-24 hours after onset of acute myocardial infarction | journal=Lancet | year=1993 | volume=342 | issue=8874 | pages=759–66 | pmid=8103874 | doi=10.1016/0140-6736(93)91538-W}}</ref> Because irreversible injury occurs within 2–4 hours of the infarction, there is a limited window of time available for reperfusion to work.
| | Reperfusion therapy is indicated in several medical conditions, primarily those involving acute blockage of blood vessels. These include: |
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| Thrombolytic drugs are contraindicated for the treatment of unstable angina and NSTEMI<ref name="FTT_Lancet"/><ref name="TIMI_IIIB">{{cite journal | pmid = 8149520 | volume=89 | issue=4 | title=Effects of tissue plasminogen activator and a comparison of early invasive and conservative strategies in unstable angina and non-Q-wave myocardial infarction. Results of the TIMI IIIB Trial. Thrombolysis in Myocardial Ischemia | date=April 1994 | journal=Circulation | pages=1545–56 | doi=10.1161/01.cir.89.4.1545}}</ref> and for the treatment of individuals with evidence of [[cardiogenic shock]].<ref name="Hochman-1999">{{cite journal |vauthors=Hochman JS, Sleeper LA, Webb JG, Sanborn TA, White HD, Talley JD, Buller CE, Jacobs AK, Slater JN, Col J, McKinlay SM, LeJemtel TH | title=Early revascularization in acute myocardial infarction complicated by cardiogenic shock. SHOCK Investigators. Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock | journal=N Engl J Med | year=1999 | volume=341 | issue=9 | pages=625–34 | pmid=10460813 | doi=10.1056/NEJM199908263410901| url=http://nrs.harvard.edu/urn-3:HUL.InstRepos:29666958 }}</ref>
| | * [[Acute myocardial infarction]] (heart attack) |
| | * [[Acute ischemic stroke]] |
| | * [[Pulmonary embolism]] |
| | * [[Peripheral artery disease]] |
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| Although no perfect thrombolytic agent exists, ideally it would lead to rapid reperfusion, have a high sustained patency rate, be specific for recent thrombi, be easily and rapidly administered, create a low risk for [[intracerebral hemorrhage|intracerebral bleeding]] and systemic bleeding, have no [[antigen]]icity, adverse [[haemodynamic response|hemodynamic effects]], or clinically significant [[drug interaction]]s, and be [[cost-effectiveness analysis#CEA in pharmacoeconomics|cost effective]].<ref name="Ideal_Thrombolytic">{{cite journal | vauthors=White HD, Van de Werf FJ | year = 1998 | title = Thrombolysis for acute myocardial infarction. | url = | journal = Circulation | volume = 97 | issue = 16| pages = 1632–46 | pmid = 9593569 | doi=10.1161/01.cir.97.16.1632}}</ref> Currently available thrombolytic agents include [[streptokinase]], [[urokinase]], and [[alteplase]] (recombinant [[tissue plasminogen activator]], rtPA). More recently, thrombolytic agents similar in structure to rtPA such as [[reteplase]] and [[tenecteplase]] have been used. These newer agents boast efficacy at least as well as rtPA with significantly easier administration. The thrombolytic agent used in a particular individual is based on institution preference and the age of the patient.
| | ==Complications== |
| | While reperfusion therapy is life-saving, it can also lead to complications. One of the most significant is [[reperfusion injury]], which occurs when the restoration of blood flow leads to inflammation and oxidative damage to the tissue. Other potential complications include bleeding, particularly with thrombolytic therapy, and vascular damage during mechanical interventions. |
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| Depending on the thrombolytic agent being used, additional [[anticoagulant|anticoagulation]] with [[heparin]] or [[low molecular weight heparin]] may be of benefit.<ref name="GUSTO-1993-1">{{cite journal | author=The GUSTO investigators | title=An international randomized trial comparing four thrombolytic strategies for acute myocardial infarction. The GUSTO investigators | journal=N Engl J Med | year=1993 | volume=329 | issue=10 | pages=673–82 | pmid=8204123 | doi=10.1056/NEJM199309023291001| hdl=1765/5468 }}</ref><ref name="Sabatine-2005">{{cite journal |vauthors=Sabatine MS, Morrow DA, Montalescot G, Dellborg M, Leiva-Pons JL, Keltai M, Murphy SA, McCabe CH, Gibson CM, Cannon CP, Antman EM, Braunwald E |others=Clopidogrel as Adjunctive Reperfusion Therapy (CLARITY)-Thrombolysis in Myocardial Infarction (TIMI) 28 Investigators. | title=Angiographic and clinical outcomes in patients receiving low-molecular-weight heparin versus unfractionated heparin in ST-elevation myocardial infarction treated with fibrinolytics in the CLARITY-TIMI 28 Trial | journal=Circulation | year=2005 | volume=112 | issue=25 | pages=3846–54 | pmid=16291601 | doi = 10.1161/CIRCULATIONAHA.105.595397}}</ref> With tPa and related agents (reteplase and tenecteplase), heparin is needed to keep the coronary artery open. Because of the anticoagulant effect of fibrinogen depletion with streptokinase<ref name="Cowley-1983">{{cite journal |vauthors=Cowley MJ, Hastillo A, Vetrovec GW, Fisher LM, Garrett R, Hess ML | title=Fibrinolytic effects of intracoronary streptokinase administration in patients with acute myocardial infarction and coronary insufficiency | journal=Circulation | year=1983 | volume=67 | issue=5 | pages=1031–8 | pmid=6831667 | doi=10.1161/01.cir.67.5.1031}}</ref> and urokinase<ref name="Lourenco-1989">{{cite journal |vauthors=Lourenco DM, Dosne AM, Kher A, Samama M | title=Effect of standard heparin and a low molecular weight heparin on thrombolytic and fibrinolytic activity of single-chain urokinase plasminogen activator ''in vitro'' | journal=Thromb Haemost | year=1989 | volume=62 | issue=3 | pages=923–6 | pmid=2556812| doi=10.1055/s-0038-1651029 }}</ref><ref name="Van de Werf-1986">{{cite journal |vauthors=Van de Werf F, Vanhaecke J, de Geest H, Verstraete M, Collen D | title=Coronary thrombolysis with recombinant single-chain urokinase-type plasminogen activator in patients with acute myocardial infarction | journal=Circulation | year=1986 | volume=74 | issue=5 | pages=1066–70 | pmid=2429783 | doi=10.1161/01.cir.74.5.1066}}</ref><ref name="Bode-1988">{{cite journal |vauthors=Bode C, Schoenermark S, Schuler G, Zimmermann R, Schwarz F, Kuebler W | title=Efficacy of intravenous prourokinase and a combination of prourokinase and urokinase in acute myocardial infarction | journal=Am J Cardiol | year=1988 | volume=61 | issue=13 | pages=971–4 | pmid=2452564 | doi = 10.1016/0002-9149(88)90108-7}}</ref> treatment, it is less necessary there.<ref name="GUSTO-1993-1"/>
| | ==Prognosis== |
| | The prognosis following reperfusion therapy depends on several factors, including the timeliness of the intervention, the extent of tissue damage prior to reperfusion, and the presence of any complications. Early intervention is critical for improving outcomes, particularly in the context of [[myocardial infarction]] and [[stroke]]. |
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| ===Failure=== | | ==Related pages== |
| Thrombolytic therapy to abort a myocardial infarction is not always effective. The degree of effectiveness of a thrombolytic agent is dependent on the time since the myocardial infarction began, with the best results occurring if the thrombolytic is used within two hours of the onset of symptoms.<ref name="Morrison-2000">{{cite journal |vauthors=Morrison LJ, Verbeek PR, McDonald AC, Sawadsky BV, Cook DJ | title=Mortality and prehospital thrombolysis for acute myocardial infarction: A meta-analysis | journal=JAMA | year=2000 | volume=283 | issue=20 | pages=2686–92 | format=[[PDF]] | url=http://jama.ama-assn.org/cgi/reprint/283/20/2686.pdf?ijkey=c72b289825a3fd6ace7545ef61cd70936485e7e1 | pmid=10819952 | doi = 10.1001/jama.283.20.2686}}</ref><ref name="Boersma-1996">{{cite journal |vauthors=Boersma E, Maas AC, Deckers JW, Simoons ML | title=Early thrombolytic treatment in acute myocardial infarction: reappraisal of the golden hour | journal=Lancet | year=1996 | volume=348 | issue=9030 | pages=771–5 | pmid=8813982 | doi = 10.1016/S0140-6736(96)02514-7| hdl=1765/58599 }}</ref> Failure rates of thrombolytics can be as high as 50%.<ref>{{cite book|last1=Katz|first1=Richard|last2=Purcell|first2=H.|title=Acute Coronary Syndromes|date=2006|publisher=Elsevier Health Sciences|isbn=0443102961|page=96|url=https://books.google.ca/books?id=MoR33Z5J7rEC&pg=PA96|language=en}}</ref> In cases of failure of the thrombolytic agent to open the infarct-related coronary artery, the person is then either treated conservatively with anticoagulants and allowed to "complete the infarction" or [[percutaneous coronary intervention]] (and coronary angioplasty) is then performed. Percutaneous coronary intervention in this setting is known as "rescue PCI" or "salvage PCI". Complications, particularly bleeding, are significantly higher with rescue PCI than with primary PCI due to the action of the thrombolytic.
| | * [[Ischemia]] |
| | * [[Thrombolysis]] |
| | * [[Coronary artery disease]] |
| | * [[Stroke]] |
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| ===Side effects===
| | [[Category:Medical treatments]] |
| Intracranial bleeding (ICB) and subsequent [[stroke]] is a serious [[adverse effect|side effect]] of thrombolytic use. The [[risk factor]]s for developing intracranial bleeding include a previous episode of intracranial bleed, advanced age of the individual, and the thrombolytic regimen that is being used. In general, the risk of ICB due to thrombolytics is between 0.5 and 1 percent.<ref name="GUSTO-1993-1" />
| | [[Category:Cardiology]] |
| | | [[Category:Neurology]] |
| ==Coronary angioplasty==
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| {{Main|Percutaneous coronary intervention}}
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| [[File:Intracoronary thrombus.png|right|thumb|[[Thrombus]] material (in a cup, upper left corner) removed from a coronary artery during an angioplasty to abort a myocardial infarction. Five pieces of thrombus are shown (arrow heads).]]
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| The benefit of prompt, primary angioplasty over thrombolytic therapy for acute STEMI is now well established.<ref name="Keeley-2003">{{cite journal |vauthors=Keeley EC, Boura JA, Grines CL | title=Primary angioplasty versus intravenous thrombolytic therapy for acute myocardial infarction: a quantitative review of 23 randomised trials | journal=Lancet | year=2003 | volume=361 | issue=9351 | pages=13–20 | pmid=12517460 | doi = 10.1016/S0140-6736(03)12113-7}}</ref><ref name="Grines-1993">{{cite journal |vauthors=Grines CL, Browne KF, Marco J, Rothbaum D, Stone GW, O'Keefe J, Overlie P, Donohue B, Chelliah N, Timmis GC, etal | title=A comparison of immediate angioplasty with thrombolytic therapy for acute myocardial infarction. The Primary Angioplasty in Myocardial Infarction Study Group | journal=N Engl J Med | year=1993 | volume=328 | issue=10 | pages=673–9 | pmid=8433725 | doi = 10.1056/NEJM199303113281001}}</ref><ref name="GUSTO-IIb">{{cite journal | author=The Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes (GUSTO IIb) Angioplasty Substudy Investigators. | title=A clinical trial comparing primary coronary angioplasty with tissue plasminogen activator for acute myocardial infarction | journal=N Engl J Med | year=1997 | volume=336 | issue=23 | pages=1621–8 | pmid=9173270 | doi=10.1056/NEJM199706053362301| hdl=1765/5545 }}</ref> When performed rapidly, an angioplasty restores flow in the blocked artery in more than 95% of patients compared with the reperfusion rate of about 65% achieved by thrombolysis.<ref name="Keeley-2003"/> Logistic and economic obstacles seem to hinder a more widespread application of angioplasty,<ref name=Boersma2006>{{cite journal | author = Boersma E, The Primary Coronary Angioplasty vs. Thrombolysis Group | year = 2006 | title = Does time matter? A pooled analysis of randomized clinical trials comparing primary percutaneous coronary intervention and in-hospital fibrinolysis in acute myocardial infarction patients | url = | journal = Eur Heart J | volume = 27 | issue = 7| pages = 779–88 | pmid = 16513663 | doi = 10.1093/eurheartj/ehi810 }}</ref> although the feasibility of providing regionalized angioplasty for STEMI is currently being explored in the United States.<ref name=Rokos_2006>{{cite journal |vauthors=Rokos IC, Larson DM, Henry TD, etal | year = 2006 | title = Rationale for establishing regional ST-elevation myocardial infarction receiving center (SRC) networks | url = | journal = Am Heart J | volume = 152 | issue = 4| pages = 661–7 | pmid = 16996830 | doi = 10.1016/j.ahj.2006.06.001 }}</ref> The use of a coronary angioplasty to abort a myocardial infarction is preceded by a primary [[percutaneous coronary intervention]]. The goal of a prompt angioplasty is to open the artery as soon as possible, and preferably within 90 minutes of the patient presenting to the emergency room. This time is referred to as the [[door-to-balloon]] time. Few hospitals can provide an angioplasty within the 90 minute interval,<ref name=Doortoballoon>{{cite journal |vauthors=Bradley EH, Herrin J, Wang Y, Barton BA, Webster TR, Mattera JA, Roumanis SA, Curtis JP, Nallamothu BK, etal | year = 2006 | title = Strategies for reducing the door-to-balloon time in acute myocardial infarction | url = | journal = N Engl J Med | volume = 355 | issue = 22| pages = 2308–20 | pmid = 17101617 | doi = 10.1056/NEJMsa063117 }}</ref> which prompted the [[American College of Cardiology]] (ACC) to launch a national Door to Balloon (D2B) Initiative in November 2006. Over 800 hospitals have joined the D2B Alliance as of March 16, 2007.<ref name="ACC-D2B">{{cite web | title=D2B: An Alliance for Quality | publisher=American College of Cardiology | year=2006 | url=http://d2b.acc.org/ | accessdate=April 15, 2007}}</ref>
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| One particularly successful implementation of a primary PCI protocol is in the [[Calgary Health Region]] under the auspices of the [[Libin Cardiovascular Institute of Alberta]]. Under this model, [[Emergency Medical Services|EMS]] teams responding to an emergency can transmit the ECG directly to a digital archiving system that allows emergency room staff to immediately confirm the diagnosis. This in turn allows for redirection of the EMS teams to those facilities that are ready to conduct time-critical angioplasty. This protocol has resulted in a median time to treatment of 62 minutes.<ref name="De Villiers-2007">{{cite journal |vauthors=De Villiers JS, Anderson T, McMeekin JD, etal | title = Expedited transfer for primary percutaneous coronary intervention: a program evaluation | journal = CMAJ | volume = 176 | pages = 1833–8 | year = 2007 | pmid = 17576980 | issue = 13 | doi = 10.1503/cmaj.060902 | pmc = 1891117}}</ref>
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| The current guidelines in the United States restrict angioplasties to hospitals with available emergency bypass surgery as a backup,<ref name="Antman-2004"/> but this is not the case in other parts of the world.<ref name="Aversano-2001">{{cite journal |vauthors=Aversano T, etal | title = Thrombolytic therapy vs primary percutaneous coronary intervention for myocardial infarction in patients presenting to hospitals without on-site cardiac surgery: a randomized controlled trial | journal = JAMA | volume = 287 | issue = 15 | pages = 1943–51 | year = 2002 | pmid = 11960536 | doi = 10.1001/jama.287.15.1943}}</ref>
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| A PCI involves performing a coronary [[angiography|angiogram]] to determine the location of the infarcting vessel, followed by [[balloon angioplasty]] (and frequently deployment of an intracoronary stent) of the [[stenosis|stenosed]] arterial segment. In some settings, an extraction catheter may be used to attempt to aspirate (remove) the thrombus prior to balloon angioplasty. While the use of intracoronary [[stent]]s do not improve the short term outcomes in primary PCI, the use of stents is widespread because of the decreased rates of procedures to treat restenosis compared to balloon angioplasty.<ref name="Grines-1999">{{cite journal |vauthors=Grines CL, Cox DA, Stone GW, Garcia E, Mattos LA, Giambartolomei A, Brodie BR, Madonna O, Eijgelshoven M, Lansky AJ, O'Neill WW, Morice MC | title=Coronary angioplasty with or without stent implantation for acute myocardial infarction. Stent Primary Angioplasty in Myocardial Infarction Study Group | journal=N Engl J Med | year=1999 | volume=341 | issue=26 | pages=1949–56 | pmid=10607811 | doi=10.1056/NEJM199912233412601}}</ref>
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| [[Adjuvant therapy]] during an angioplasty includes intravenous [[heparin]], [[aspirin]], and [[clopidogrel]]. [[Glycoprotein IIb/IIIa inhibitor]]s are often used in the setting of primary angioplasty to reduce the risk of ischemic complications during the procedure.<ref name="Brener-1998">{{cite journal |vauthors=Brener SJ, Barr LA, Burchenal JE, Katz S, George BS, Jones AA, Cohen ED, Gainey PC, White HJ, Cheek HB, Moses JW, Moliterno DJ, Effron MB, Topol EJ | title=Randomized, placebo-controlled trial of platelet glycoprotein IIb/IIIa blockade with primary angioplasty for acute myocardial infarction. ReoPro and Primary PTCA Organization and Randomized Trial (RAPPORT) Investigators | journal=Circulation | year=1998 | volume=98 | issue=8 | pages=734–41 | pmid=9727542 | doi=10.1161/01.cir.98.8.734}}</ref><ref name="Tcheng-2003-1">{{cite journal | vauthors=Tcheng JE, Kandzari DE, Grines CL, Cox DA, Effron MB, Garcia E, Griffin JJ, Guagliumi G, Stuckey T, Turco M, Fahy M, Lansky AJ, Mehran R, Stone GW | title=Benefits and risks of abciximab use in primary angioplasty for acute myocardial infarction: the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial | journal=Circulation | year=2003 | volume=108 | issue=11 | pages=1316–23 | pmid=12939213 | doi = 10.1161/01.CIR.0000087601.45803.86}}</ref> Due to the number of antiplatelet agents and anticoagulants used during primary angioplasty, the risk of bleeding associated with the procedure is higher than during an elective procedure.<ref>{{cite book |title=900 Questions: An Interventional Cardiology Board Review |last=Mukherjee |first=Debabrata |year=2006 |publisher=Lippincott Williams & Wilkins |isbn=0-7817-7349-0 }}</ref> | |
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| ==Coronary artery bypass surgery==
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| {{Main|Coronary artery bypass graft surgery}}
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| [[File:Coronary artery bypass surgery Image 657B-PH.jpg|thumb|right|Coronary artery bypass surgery during mobilization (freeing) of the [[right coronary artery]] from its surrounding tissue, [[adipose tissue]] (yellow). The tube visible at the bottom is the aortic cannula (returns blood from the [[Heart-lung machine|HLM]]). The tube above it (obscured by the [[cardiac surgeon|surgeon]] on the right) is the venous cannula (receives blood from the body). The patient's [[heart]] is stopped and the [[aorta]] is cross-clamped. The patient's head (not seen) is at the bottom.]]
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| Emergency bypass surgery for the treatment of an acute myocardial infarction (MI) is less common than PCI or thrombolysis. From 1995 to 2004, the percentage of people with [[cardiogenic shock]] treated with primary PCI rose from 27.4% to 54.4%, while the increase in [[coronary artery bypass graft surgery]] (CABG) was only from 2.1% to 3.2%.<ref name=NRMI>{{cite journal |vauthors=Babaev A, Frederick PD, Pasta DJ, Every N, Sichrovsky T, Hochman JS |title=Trends in management and outcomes of patients with acute myocardial infarction complicated by cardiogenic shock |journal=JAMA |volume=294 |issue=4 |pages=448–54 |year=2005 |pmid=16046651 |doi=10.1001/jama.294.4.448 |url=http://jama.ama-assn.org/cgi/pmidlookup?view=long&pmid=16046651}}</ref> Emergency CABG is usually undertaken to simultaneously treat a mechanical complication, such as a ruptured papillary muscle, or a ventricular septal defect, with ensuing cardiogenic shock.<ref name=Sabiston>{{cite book | last =Townsend | first =Courtney M. |author2=Beauchamp D.R. |author3=Evers M.B. |author4=Mattox K.L. | title =Sabiston Textbook of Surgery - The Biological Basis of Modern Surgical Practice | publisher =Elsevier Saunders | year =2004 | location =Philadelphia, Pennsylvania | pages =1871 | url =http://www.elsevier.com/wps/find/bookdescription.cws_home/701163/description#description | isbn =0-7216-0409-9}}</ref> In uncomplicated MI, the [[mortality rate]] can be high when the surgery is performed immediately following the infarction.<ref name=Timing1>{{cite journal |vauthors=Kaul TK, Fields BL, Riggins SL, Dacumos GC, Wyatt DA, Jones CR |title=Coronary artery bypass grafting within 30 days of an acute myocardial infarction |journal=Ann. Thorac. Surg. |volume=59 |issue=5 |pages=1169–76 |year=1995 |pmid=7733715 |doi= 10.1016/0003-4975(95)00125-5}}</ref> If this option is entertained, the patient should be stabilized prior to surgery, with supportive interventions such as the use of an [[intra-aortic balloon pump]].<ref name=Timing2>{{cite journal |vauthors=Creswell LL, Moulton MJ, Cox JL, Rosenbloom M |title=Revascularization after acute myocardial infarction |journal=Ann. Thorac. Surg. |volume=60 |issue=1 |pages=19–26 |year=1995 |pmid=7598589 |doi= 10.1016/s0003-4975(95)00351-7}}</ref> In patients developing cardiogenic shock after a myocardial infarction, both PCI and CABG are satisfactory treatment options, with similar survival rates.<ref name=SHOCK>{{cite journal |vauthors=White HD, Assmann SF, Sanborn TA, etal |title=Comparison of percutaneous coronary intervention and coronary artery bypass grafting after acute myocardial infarction complicated by cardiogenic shock: results from the Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock (SHOCK) trial |journal=Circulation |volume=112 |issue=13 |pages=1992–2001 |year=2005 |pmid=16186436 |doi=10.1161/CIRCULATIONAHA.105.540948 |url=http://circ.ahajournals.org/cgi/pmidlookup?view=long&pmid=16186436}}</ref><ref name="Hochman-2006">{{cite journal | vauthors=Hochman JS, Sleeper LA, Webb JG, Dzavik V, Buller CE, Aylward P, Col J, White HD | title=Early revascularization and long-term survival in cardiogenic shock complicating acute myocardial infarction | journal=JAMA | year=2006 | volume=295 | issue=21 | pages=2511–5 | pmid=16757723 | doi = 10.1001/jama.295.21.2511 | pmc=1782030}}</ref>
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| Coronary artery bypass surgery involves an artery or vein from the patient being implanted to bypass [[stenosis|narrowings]] or occlusions in the coronary arteries. Several arteries and veins can be used, however [[internal mammary artery]] grafts have demonstrated significantly better long-term patency rates than [[great saphenous vein]] grafts.<ref name=Raja2004>{{cite journal |vauthors=Raja SG, Haider Z, Ahmad M, Zaman H |title=Saphenous vein grafts: to use or not to use? |journal=Heart Lung Circ |volume=13 |issue=4 |pages=403–9 |year=2004 |pmid=16352226 |doi=10.1016/j.hlc.2004.04.004 }}</ref> In patients with two or more coronary arteries affected, bypass surgery is associated with higher long-term [[survival rate]]s compared to percutaneous interventions.<ref name=Hannan2005>{{cite journal |vauthors=Hannan EL, Racz MJ, Walford G, etal |title=Long-term outcomes of coronary-artery bypass grafting versus stent implantation |journal=N. Engl. J. Med. |volume=352 |issue=21 |pages=2174–83 |year=2005 |pmid=15917382 |doi=10.1056/NEJMoa040316 }}</ref> In patients with single vessel disease, surgery is comparably safe and effective, and may be a treatment option in selected cases.<ref name=Bourassa2000>{{cite journal |author=Bourassa MG |title=Clinical trials of coronary revascularization: coronary angioplasty vs. coronary bypass grafting |journal=Curr. Opin. Cardiol. |volume=15 |issue=4 |pages=281–6 |year=2000 |pmid=11139092 |doi= 10.1097/00001573-200007000-00013|url=http://meta.wkhealth.com/pt/pt-core/template-journal/lwwgateway/media/landingpage.htm?issn=0268-4705&volume=15&issue=4&spage=281}}</ref> Bypass surgery has higher costs initially, but becomes [[Cost-effectiveness|cost-effective]] in the long term.<ref name=Hlatky2004>{{cite journal |vauthors=Hlatky MA, Boothroyd DB, Melsop KA, etal |title=Medical costs and quality of life 10 to 12 years after randomization to angioplasty or bypass surgery for multivessel coronary artery disease |journal=Circulation |volume=110 |issue=14 |pages=1960–6 |year=2004 |pmid=15451795 |doi=10.1161/01.CIR.0000143379.26342.5C |url=http://circ.ahajournals.org/cgi/pmidlookup?view=long&pmid=15451795}}</ref> A surgical bypass graft is more [[Invasive (medical)|invasive]] initially but bears less risk of recurrent procedures (but these may be again [[Minimally invasive procedure|minimally invasive]]).<ref name=Bourassa2000/>
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| ==Reperfusion arrhythmia==
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| [[Accelerated idioventricular rhythm]] which looks like slow [[ventricular tachycardia]] is a sign of a successful reperfusion.<ref>{{cite journal |vauthors=Osmancik PP, Stros P, Herman D |title=In-hospital arrhythmias in patients with acute myocardial infarction - the relation to the reperfusion strategy and their prognostic impact |journal=Acute Card Care |volume=10 |issue=1 |pages=15–25 |year=2008 |pmid=17924228 |doi=10.1080/17482940701474478 |url=}}</ref> No treatment of this rhythm is needed as it rarely changes into a more serious rhythm.<ref>{{cite journal |vauthors=Dalzell JR, Jackson CE |title=When the rhythm makes the diagnosis |journal=J Emerg Med |volume= 41|issue= 2|pages= 182–4|date=April 2009 |pmid=19345050 |doi=10.1016/j.jemermed.2009.02.028 |url=}}</ref>
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| ==See also==
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| * [[Perfusion scanning]]
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| * [[Reperfusion injury]]
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| * [[Revascularization]]
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| * [[TIMI]]
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| * [[Ischemia-reperfusion injury of the appendicular musculoskeletal system]]
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| ==References==
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| {{Reflist|32em}}
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| [[Category:Cardiac procedures]] | |
Medical treatment to restore blood flow
Reperfusion therapy is a medical treatment aimed at restoring blood flow to tissue that has been deprived of oxygen and nutrients due to a blockage in the blood vessels. This therapy is crucial in the management of ischemic heart disease, stroke, and other conditions where blood supply is compromised.
Mechanism of Action
Reperfusion therapy works by reopening blocked blood vessels, thereby restoring blood flow to the affected tissue. This can be achieved through various methods, including pharmacological and mechanical interventions. The primary goal is to minimize tissue damage and preserve organ function.
Pharmacological Reperfusion
Pharmacological reperfusion involves the use of drugs to dissolve blood clots. The most common agents used are thrombolytics, which include medications such as alteplase, reteplase, and tenecteplase. These drugs work by activating the body's fibrinolytic system to break down the fibrin in blood clots.
Mechanical Reperfusion
Mechanical reperfusion is achieved through procedures such as percutaneous coronary intervention (PCI) and thrombectomy. PCI involves the use of a balloon catheter to open up blocked coronary arteries, often followed by the placement of a stent to keep the artery open. Thrombectomy is a procedure used to physically remove clots from blood vessels, commonly used in the treatment of acute ischemic stroke.
Indications
Reperfusion therapy is indicated in several medical conditions, primarily those involving acute blockage of blood vessels. These include:
Complications
While reperfusion therapy is life-saving, it can also lead to complications. One of the most significant is reperfusion injury, which occurs when the restoration of blood flow leads to inflammation and oxidative damage to the tissue. Other potential complications include bleeding, particularly with thrombolytic therapy, and vascular damage during mechanical interventions.
Prognosis
The prognosis following reperfusion therapy depends on several factors, including the timeliness of the intervention, the extent of tissue damage prior to reperfusion, and the presence of any complications. Early intervention is critical for improving outcomes, particularly in the context of myocardial infarction and stroke.
Related pages
