Reperfusion therapy

Reperfusion therapy
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).

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 drugs and surgery. The drugs are thrombolytics and fibrinolytics used in a process called thrombolysis. Surgeries performed may be minimally-invasive endovascular procedures such as a percutaneous coronary intervention (PCI), which involves coronary angioplasty. The angioplasty uses the insertion of a balloon and/or stents to open up the artery.[1] Other surgeries performed are the more invasive bypass surgeries that graft arteries around blockages.

If an MI is presented with ECG evidence of an ST elevation known as 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 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.[2] 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.[3]

At least 10% of treated cases of STEMI do not develop necrosis of the 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.[4]

  1. ^ McCoy SS, Crowson CS, Maradit-Kremers H, Therneau TM, Roger VL, Matteson EL, Gabriel SE (May 2013). "Longterm Outcomes and Treatment After Myocardial Infarction in Patients with Rheumatoid Arthritis". The Journal of Rheumatology. 40 (5): 605–10. doi:10.3899/jrheum.120941. PMC 3895921. PMID 23418388.
  2. ^ "Effects of tissue plasminogen activator and a comparison of early invasive and conservative strategies in unstable angina and non-Q-wave myocardial... - PubMed - NCBI". Circulation. 89 (4): 1545–1556. April 1994. doi:10.1161/01.cir.89.4.1545. PMID 8149520.
  3. ^ Fibrinolytic Therapy Trialists' (FTT) Collaborative Group (1994). "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". Lancet. 343 (8893): 311–22. doi:10.1016/s0140-6736(94)91161-4. PMID 7905143.
  4. ^ Verheugt FW, Gersh BJ, Armstrong PW (2006). "Aborted myocardial infarction: a new target for reperfusion therapy". Eur Heart J. 27 (8): 901–4. doi:10.1093/eurheartj/ehi829. PMID 16543251.