Editing Circulatory system (section)

==Clinical significance==
{{Further|List of circulatory system conditions}}
{{anchor|Health and disease}}
Many diseases affect the circulatory system. These include a number of [[cardiovascular disease]]s, affecting the heart and blood vessels; [[hematologic disease]]s that affect the blood, such as [[anemia]], and [[lymphatic disease]]s affecting the lymphatic system. [[Cardiologist]]s are medical professionals which specialise in the heart, and [[cardiothoracic surgeon]]s specialise in operating on the heart and its surrounding areas. [[Vascular surgeon]]s focus on the blood vessels.

===Cardiovascular disease===
{{Main|Cardiovascular disease}}
Diseases affecting the cardiovascular system are called ''cardiovascular disease''.

Many of these diseases are called "[[lifestyle disease]]s" because they develop over time and are related to a person's exercise habits, diet, whether they smoke, and other lifestyle choices a person makes. [[Atherosclerosis]] is the precursor to many of these diseases. It is where small [[Atheroma|atheromatous plaques]] build up in the walls of medium and large arteries. This may eventually grow or rupture to occlude the arteries. It is also a risk factor for [[acute coronary syndrome]]s, which are diseases that are characterised by a sudden deficit of oxygenated blood to the heart tissue. Atherosclerosis is also associated with problems such as [[aneurysm]] formation or splitting ("dissection") of arteries.

Another major cardiovascular disease involves the creation of a [[Thrombus|clot, called a "thrombus"]]. These can originate in veins or arteries. [[Deep venous thrombosis]], which mostly occurs in the legs, is one cause of clots in the veins of the legs, particularly when a person has been stationary for a long time. These clots may [[Embolus|embolise]], meaning travel to another location in the body. The results of this may include [[pulmonary embolus]], [[transient ischaemic attack]]s, or [[stroke]].

Cardiovascular diseases may also be congenital in nature, such as [[Congenital heart defect|heart defects]] or [[persistent fetal circulation]], where the circulatory changes that are supposed to happen after birth do not. Not all congenital changes to the circulatory system are associated with diseases, a large number are [[anatomical variation]]s.

===Investigations===
[[File:Arteria-lusoria MRA MIP.gif|thumb|[[Magnetic resonance angiography]] of [[aberrant subclavian artery]]]]
The function and health of the circulatory system and its parts are measured in a variety of manual and automated ways. These include simple methods such as those that are part of the [[cardiovascular examination]], including the taking of a person's [[pulse]] as an indicator of a person's [[heart rate]], the taking of [[blood pressure]] through a [[sphygmomanometer]] or the use of a [[stethoscope]] to listen to the heart for [[cardiac murmur|murmurs]] which may indicate problems with the [[heart valve|heart's valves]]. An [[electrocardiogram]] can also be used to evaluate the way in which electricity is conducted through the heart.

Other more invasive means can also be used. A [[cannula]] or [[catheter]] inserted into an artery may be used to measure [[pulse pressure]] or [[pulmonary wedge pressure]]s. Angiography, which involves injecting a dye into an artery to visualise an arterial tree, can be used in the heart ([[coronary angiography]]) or brain. At the same time as the arteries are visualised, blockages or narrowings may be fixed through the insertion of [[stent]]s, and active bleeds may be managed by the insertion of coils. An MRI may be used to image arteries, called an [[magnetic resonance angiography|MRI angiogram]]. For evaluation of the blood supply to the lungs a [[CT pulmonary angiogram]] may be used. [[Doppler ultrasonography#Blood vessels|Vascular ultrasonography]] may be used to investigate [[vascular disease]]s affecting the [[venous system]] and the [[arterial system]] including the diagnosis of [[stenosis]], [[Ultrasonography of deep venous thrombosis|thrombosis]] or [[Ultrasonography of chronic venous insufficiency of the legs|venous insufficiency]]. An [[intravascular ultrasound]] using a [[catheter]] is also an option.

===Surgery===
{{expand section|date=March 2015}}

{{Further|Vascular surgery|Vascular bypass}}
There are a number of surgical procedures performed on the circulatory system:
* [[Coronary artery bypass surgery]]
* [[Coronary stent]] used in [[angioplasty]]
* [[Vascular surgery]]
* [[Vein stripping]]
* Cosmetic procedures

Cardiovascular procedures are more likely to be performed in an inpatient setting than in an ambulatory care setting; in the United States, only 28% of cardiovascular surgeries were performed in the ambulatory care setting.<ref>{{cite journal | vauthors = Wier LM, Steiner CA, Owens PL | title = Surgeries in Hospital-Owned Outpatient Facilities, 2012 | journal =HCUP Statistical Brief |issue=188 | publisher = Agency for Healthcare Research and Quality | location = Rockville, MD | date = April 17, 2015 | url = https://www.hcup-us.ahrq.gov/reports/statbriefs/sb188-Surgeries-Hospital-Outpatient-Facilities-2012.jsp | archive-url = https://web.archive.org/web/20150312035159/http://www.hcup-us.ahrq.gov/reports/statbriefs/sb188-Surgeries-Hospital-Outpatient-Facilities-2012.jsp | url-status = dead | archive-date = March 12, 2015 }}</ref>