View source for Intra-aortic balloon pump

[[File:Dscp Iab.JPG|thumb|right|An intra-aortic balloon pump]]
The '''Intra-aortic balloon pump''' '''(IABP)''' is a mechanical device that decreases [[myocardium|myocardial]] [[oxygen]] demand while at the same time increasing [[cardiac output]]. Increasing cardiac output increases coronary [[blood]] flow and therefore myocardial oxygen delivery. It consists of a cylindrical polyethylene balloon that sits in the [[aorta]], approximately {{cm to in|2}} from the left [[subclavian artery]]<ref name="THI"> 
http://www.texasheart.org/Research/Devices/iabp.cfm Intra-aortic Balloon Pump Texas Heart Institute</ref> and counterpulsates. That is, it actively deflates in [[Systole (medicine)|systole]], increasing forward blood flow by reducing [[afterload]]. It actively inflates in [[diastole]], increasing blood flow to the [[coronary artery|coronary arteries]]. These actions combine to decrease myocardial oxygen demand and increase myocardial oxygen supply.<ref name="IrwinRippe">
 [http://www.lww.com/product/?0-7817-3548-3 Intensive Care Medicine] by Irwin and Rippe</ref>
<ref name="IJTCS">
[http://www.rjmatthewsmd.com/Definitions/IABP_Counterpulsation.htm Intra Aortic Balloon Pump (IABP) Counterpulsation] [http://www.uam.es/departamentos/medicina/anesnet/journals/ijeicm/vol3n2/iabp.htm mirror with better quality] by P. J Overwalder, M.D., Department of Surgery, Division of Cardiac Surgery, University Hospital Graz, The Internet Journal of Thoracic and Cardiovascular Surgery. 1999. Volume 2 Number 2.</ref>
<ref name="HongKong"> 
[http://www.aic.cuhk.edu.hk/web8/IABP.htm Intra-aortic balloon pumping] Department of Anaesthesia and Intensive Care of The Chinese University of [[Hong Kong]]</ref>

A computer-controlled mechanism inflates the balloon with [[helium]] from a cylinder during diastole, usually linked to either an [[electrocardiogram]] (ECG) or a pressure [[transducer]] at the [[distal]] tip of the [[catheter]]; some IABPs, such as the Datascope System 98XT, allow asynchronous counterpulsation at a set rate, though this setting is rarely used. Helium is used because its low viscosity allows it to travel quickly through the long connecting tubes, and has a lower risk of causing an [[embolism]] should the balloon rupture.

==History==
The IABP device was pioneered at Grace Sinai Hospital in Detroit during the early 1960s by 
Dr. [[Adrian Kantrowitz]] and his team.<ref name="IJTCS"/> The device was developed for use in [[heart surgery]] by Dr. David Bregman in 1976 at [[NewYork-Presbyterian Hospital]] in [[New York City]].<ref>
"NewYork-Presbyterian Heart 'Firsts'", available at [http://www.nyp.org/about/heart-firsts.html http://www.nyp.org/about/heart-firsts.html]</ref>

The first clinical implant was performed at Maimonides Hospital, Brooklyn, N.Y. in Oct., 1967. The patient, a 48  year old woman, was in cardiogenic shock and unresponsive to traditional therapy. An IABP was inserted by a cut down on the left [[femoral artery]]. Pumping was performed for approximately 6 hours. Shock reversed and the patient was discharged.

The size of the original ballon was 15 [[French catheter scale|French]] but eventually 9 and 8 [[French catheter scale|French]] balloons were developed.<ref name="Overwalder">
http://www.rjmatthewsmd.com/Definitions/IABP_Counterpulsation.htm Intra Aortic Balloon Pump (IABP) Counterpulsation by P. J Overwalder, M.D.</ref> A second operation removed the balloon. Since 1979 the placement of the balloon has been modified using the Seldinger technique.<ref name="Overwalder"/><ref>
Kantrowitz, A., Tjonneland, S., Freed, P.S., Phillips, S.J., Butner, A.N., Sherman, J.L., Jr.:  Initial clinical experience with intra-aortic balloon pumping in cardiogenic shock.  JAMA, 1968; 203(2):113-8</ref>

==Indications==
The following situations may benefit from this device.<ref name="IrwinRippe"/><ref name="IJTCS"/><ref name="HongKong"/>
*[[Cardiogenic shock]] when used alone as treatment for [[myocardial infarction]]. 9-22% survive the first year.
*Reversible [[heart|intracardial]] mechanical defects complicating infarction, i.e. acute [[mitral valve|mitral]] regurgitation and [[septal]] perforation.
*Unstable [[angina pectoris]] benefits from counterpulsation.
*Post [[cardiothoracic surgery]]&mdash;most common and useful is counterpulsation in weaning patients from [[cardiopulmonary bypass]] after continued perioperative injury to myocardial tissue.
*Preoperative use is suggested for high-risk patients such as those with unstable [[angina]] with [[stenosis]] greater than 70% of main coronary artery, in [[ventricular]] dysfunction with an [[ejection fraction]] less than 35%.
*[[PTCA|Percutaneous coronary angioplasty]]
*In high risk [[coronary artery bypass]] graft surgery where cardiopulmonary bypass time was shortened, as well as during intubation period and hospital stay.<ref name="Shankar">
http://web.ebscohost.com.libdb.njit.edu:8888/ehost/pdfviewer/pdfviewer?vid=6&hid=8&sid=bc1d9530-2ffc-4265-9212-6d96ecac5381%40sessionmgr10 Usage of Intra-Aortic Balloon Pump in High Risk Coronary Artery Bypass Graft Surgery by K. Jai Shankar</ref>
*[[Thrombolytic]] therapy of acute myocardial infarction.<ref name="Overwalder"/>

==Contraindications==
===Absolute contraindication===
The following conditions will always exclude patients for treatment:<ref name="IrwinRippe"/>
<ref name="IJTCS"/>
<ref name="HongKong"/>
*Severe [[aortic valve]] insufficiency
*[[Aortic dissection]]
*Severe [[aortoiliac occlusive disease]]

===Relative contraindication===
The following conditions could, under pressing circumstances, indicate IABP therapy:<ref name="IrwinRippe"/>
*[[Prosthetic]] [[vascular]] grafts in the [[aorta]]
*Aortic [[aneurysm]]
*Aortofemoral grafts

==Complications==
Since the device is placed in the [[femoral artery]] and aorta it could provoke [[ischemia]], and [[compartment syndrome]]. The leg is at highest risk because it is supplied by the femoral artery may become ischemic. Placing the balloon too [[distal]] from the [[aortic arch|arcus aortae]] may induce occlusion of the [[renal artery]] and subsequent [[renal failure]]. Other possible complications are [[cerebral embolism]] during insertion, infection, [[dissection]] of the aorta or [[iliac artery]], perforation of the artery and [[hemorrhage]] in the [[mediastinum]]. Mechanical failure of the balloon itself is also a risk which entails vascular surgery to remove under that circumstance. After balloon removal there is also a risk of 'embolic shower' from micro clots that have formed on the surface of the balloon, and can lead to peripheral thrombosis, [[myocardial ischemia]], hemodynamic decompensation, and late [[pseudoaneurysm]].<ref name="IrwinRippe"/>
<ref name="IJTCS"/>
<ref name="HongKong"/>

==See also==
*[[Cardiogenic shock]]
*[[Ventricular assist device]]

==References==
<references/>

==External links==
*[http://texasheart.org/Research/Devices/iabp.cfm Intra-italheartj.org/pdf_files/20050080.pdf Images in cardiovascular medicine The missing intra-aortic balloon pump catheter] by Pasquale Totaro, Nello Degno, John Smith, Vincenzo Argano, Cardiac Surgery Department, Regional Cardiac Center, Morriston Hospital, Swansea, UK, Ital Heart J 2005; 6 (4): 361-362)

{{Intensive care medicine}}

[[Category:Medical pumps]]
[[Category:Cardiology]]

[[de:Intraaortale Ballonpumpe]]
[[es:Balón intraaórtico de contrapulsación]]
[[it:Contropulsatore aortico]]
[[ru:Внутриаортальная баллонная контрпульсация]]
[[uk:Аортальна балонна контрапульсація]]
[[Category:2Fix]]