|
|
| (107 intermediate revisions by 13 users not shown) |
| Line 1: |
Line 1: |
| {{DiseaseDisorder infobox | | | __NOTOC__ |
| Name = Cardiogenic shock |
| | {| class="infobox" style="float: right;" |
| ICD10 = {{ICD10|R|57|0|r|50}} |
| | | style="vertical-align: middle; padding: 5px;" align=center | [[File:Siren.gif|30px|link=Cardiogenic shock resident survival guide]] |
| ICD9 = {{ICD9|785.51}} |
| | | style="vertical-align: middle; padding: 5px;" align=center | [[Cardiogenic shock resident survival guide|'''Resident'''<br>'''Survival'''<br>'''Guide''']] |
| }}
| | |} |
| | {{Cardiogenic shock}} |
| | '''For patient information, click [[Cardiogenic shock (patient information)|here]].''' |
|
| |
|
| {{Search infobox}} | | {{CMG}}; {{AE}} {{JS}} {{AEL}}, {{sali}} |
|
| |
|
| {{CMG}}
| | ==[[Cardiogenic shock overview|Overview]]== |
|
| |
|
| {{Editor Help}}
| | ==[[Cardiogenic shock historical perspective|Historical Perspective]]== |
|
| |
|
| ==Overview== | | ==[[Cardiogenic shock classification|Classification]]== |
| '''Cardiogenic shock''' is defined as an inadequate [[cardiac output]] to maintain adequate perfusion of vital organs to meet ongoing demands for oxygenation and metabolic demands. Cardiogenic shock is due to either inadequate left ventricular pump function (such as in [[congestive heart failure]]) or inadequate left ventricular filling (such as in [[cardiac tamponade]] or [[mitral stenosis]] with tachycardia). In so far as the course of treatment differs substantially, cardiogenic shock should be distinguished from other forms of shock such as [[septic shock]] and [[neurogenic shock]].
| |
|
| |
|
| | ==[[Cardiogenic shock pathophysiology|Pathophysiology]]== |
|
| |
|
| | ==[[Cardiogenic shock causes|Causes]]== |
|
| |
|
| == Definition == | | ==[[Cardiogenic shock differential diagnosis|Differentiating Cardiogenic shock from other Diseases]]== |
|
| |
|
| Cardiogenic shock is defined by sustained [[hypotension]] with tissue hypoperfusion despite adequate left ventricular filling pressure. Signs of tissue hypoperfusion include [[oliguria]] (<30 mL/h), cool extremities, and altered mentation. | | ==[[Cardiogenic shock epidemiology and demographics|Epidemiology and Demographics]]== |
|
| |
|
| The pathophysiology of cardiogenic shock is complex and multifaceted, and as a result, diagnostic criteria for cardiogenic shock have been debated. Some clinicians argue that [[hypotension]] alone should not be the key criteria in so far as compensatory tachycardia and vasoconstriction may compensate for the reduced [[cardiac output]] to yield a mildly depressed [[systolic blood pressure]]. These clinicians advocate a hemodynamic definition with greater reliance placed on hemodynamic measures and interpretation of the [[cardiac output]] in the context of left ventricular filling pressure as often gauged by the [[pulmonary capillary wedge pressure]]. For instance, a patient who has a history of hypertension who now has a blood pressure of 100 mm Hg with a markedly elevated [[systemic vascular resistance]] ([[SVR]]) and pronounced [[tachycardia]] with a markedly reduced [[cardiac output]], would be in cardiogenic shock in the judgement of some clinicians despite the absence of [[hypotension]].
| | ==[[Cardiogenic shock risk factors|Risk Factors]]== |
|
| |
|
| In clinical trials, cardiogenic shock has been defined as follows by the SHOCK investigators: <ref>Hochman JS, Sleeper LA, Webb JG, et al. Early revascularization in acute myocardial infarction complicated by cardiogenic shock. SHOCK Investigators. Should We Emergently Revascularize Occluded Coronaries for Cardiogenic Shock. N Engl J Med 1999; 341 (9) : 625–34.</ref>
| | ==[[Cardiogenic shock natural history, complications and prognosis|Natural History, Complications and Prognosis]]== |
|
| |
|
| ===Clinical criteria=== | | ==Diagnosis== |
| # Systolic blood pressure <90 mm Hg for at least 30 minutes
| |
| # Evidence of hypoperfusion
| |
| # Cool, clammy periphery
| |
| # Decreased urine output
| |
| # Decreased level of consciousness
| |
|
| |
|
| ===Hemodynamic criteria===
| | [[Cardiogenic shock diagnostic evaluation|Diagnostic Evaluation]] | [[Cardiogenic shock history and symptoms|History and Symptoms]] | [[Cardiogenic shock physical examination|Physical Examination]] | [[Cardiogenic shock laboratory findings|Laboratory Findings]] | [[Cardiogenic shock electrocardiogram|Electrocardiogram]] | [[Cardiogenic shock chest x ray|Chest X Ray]] | [[Cardiogenic shock CT|CT]] | [[Cardiogenic shock MRI|MRI]] | |
| # Left ventricular end diastolic pressure or pulmonary capillary wedge pressure >15 mm Hg
| | [[Cardiogenic shock echocardiography or ultrasound|Echocardiography or Ultrasound]] | [[Cardiogenic shock other imaging findings|Other Imaging Findings]] | [[Cardiogenic shock other diagnostic studies|Other Diagnostic Studies]] |
| # Cardiac index <2.2 L/min/m2
| |
|
| |
|
| == Pathophysiology of Cardiogenic Shock == | | ==Treatment== |
| ===Basic hemodynamic derangements===
| |
| Cardiogenic shock is due to inadequate forward output of the heart. This can be due to the following (either alone or often in combination):
| |
| *Systolic left ventricular dysfunction (e.g. acute MI, [[CHF]], [[Cardiomyopathy]], [[myocarditis]]). It is often said that 40% of the left ventricle must be infarcted to have cardogenic shock.
| |
| *Diastolic left ventricular dysfunction (e.g. ischemia)
| |
| *Obstruction of left ventricular outflow (e.g. [[aortic stenosis]], [[HOCM]])
| |
| *Reversal of flow into the left ventricle (e.g. acute [[aortic insufficiency]])
| |
| *Inadequate left ventricular filling due to mechanical causes (e.g. [[tamponade]])
| |
| *Inadequate left ventricular filling due to inadequate filling time (e.g. tachycardia)
| |
| *A mechanical defect (e.g. a [[VSD]])
| |
|
| |
|
| ===The impact of cardiogenic shock on the [[pressure-volume loop]]===
| | [[Cardiogenic shock medical therapy|Medical Therapy]] | [[Cardiogenic shock surgery|Surgery]] | [[Cardiogenic shock primary prevention|Primary Prevention]] | [[Cardiogenic shock secondary prevention|Secondary Prevention]] | [[Cardiogenic shock cost-effectiveness of therapy|Cost-Effectiveness of Therapy]] | [[Cardiogenic shock future or investigational therapies|Future or Investigational Therapies]] |
| Cardiogenic shock shifts the pressure volume loop to the right: that is to say at a given pressure, the heart is able to eject less blood per heart beat, and [[stroke volume]] is reduced. Diastolic compliance is reduced, and left ventricular volumes are increased. This leads to the classic observation that an increased left ventricular end diastolic pressure is required to maintain adequate [[cardiac output]]. | |
|
| |
|
| ===The pathophysiologic "spiral" of cardiogenic shock=== | | ==Case Studies== |
| Among patients with acute MI, there is often a downward spiral of hypoperfusion leading to further ischemia which leads to a further reduction in cardiac output and further hypoperfusion. Patients with cardiogenic shock in the setting of STEMI more often have multivessel disease, and there may be ischemia in multiple territories. It is for this reason that multivessel angioplasty may be of benefit in the patient with cardiogenic shock. Nonculprit or remote territories may also exhibit [[myocardial stunning]] in response to an ischmeic insult which further reduces myocardial function. The pathophysiology of myocardial stunning is multifactorial and involves calcium overload in the sarcolemma and "stone heart" or diastolic dysfunction as well as the release of myocardial depressant substances. Areas of stunned myocardium may remain stunned after revascularization, but these regions do respond to inotropic stimulation. In contrast to stunned myocardium, hibernating myocardium does respond earlier to revascularization. <ref>http://emedicine.medscape.com/article/152191-overview</ref>
| |
|
| |
|
| The multifactorial nature of cardiogenic shock can be demonstrated in a patient with critical aortic stenosis who has "spiraled": There is impairment of left ventricular outflow, with a drop in cardiac output there is greater subendocardial ischemia and poorer flow in the coronary arteries, this leads to further left ventricular systolic function, given the subendocardial ischemia, the left ventricle developes diastolic dysfunction and becomes harder to fill. Inadvertent administration of [[vasodilator]]s and [[venodilator]]s may further reduce cardiac output and accelarate or trigger such a spiral.
| | [[Cardiogenic shock case study one|Case #1]] |
|
| |
|
| ===Pathophysiologic mechanisms to compensate for cardiogenic shock=== | | ==Related Chapters== |
| [[Cardiac output]] is the product of [[stroke volume]] and heart rate. In order to compensate for a reduction in stroke volume, there is a rise in the heart rate in patients with cardiogenic shock.
| |
|
| |
|
| ===Pahtophysiology of multiorgan failure===
| |
| The poor perfusion of organs results in [[hypoxia]] and [[metabolic acidosis]]. Inadequate perfusion to meet the metabolic demands of the brain, kidneys and heart leads to multiorgan failure.
| |
|
| |
| ==Differential diagnosis of underlying causes of cardiogenic shock==
| |
| Cardiogenic shock can be a complication of the following conitions:
| |
|
| |
| *[[Acute MI]], more often [[ST elevation MI]] than non ST elevation MI (NSTEMI) or [[unstable angina]]. Anterior MI with pronounced left ventricular dysfunction, posterior MI with acute [[mitral regurgitation]] or [[papillary muscle rupture]], and inferior MI with [[right ventricular infarct]] physiology can be associated with cardiogenic shock.
| |
| *[[Tachyarrhythmia]]s resulting in inadequate ventricular filling times and inadequate forward [[cardiac output]]
| |
| *[[Congestive heart failure]]
| |
| *[[Cardiomyopathy]], particularly in its end stages
| |
| *[[Valvular heart disease]] including [[aortic stenosis]], acute [[aortic insufficiency]] or [[mitral stenosis]] with [[tachycardia]] and inadequate diastolic filling time.
| |
| *[[Aortic dissection]]
| |
| *[[Hypertrophic obstructive cardiomyopathy]] with systolic anterior motion (SAM)
| |
| *[[Ventricular septal defect]]
| |
| *[[Cardiac tamponade]]
| |
| *[[Myocarditis]]
| |
| *Iatrogenic due to excess administration of vasodilators and venodilators
| |
|
| |
| == Diagnosis ==
| |
|
| |
| === Symptoms ===
| |
| * [[Anxiety]], agitation, restlessness, and an [[Glasgow Coma Scale|altered mental state]] including flacid [[coma]] may be present due to decreased cerebral perfusion and ensuing [[hypoxia (medical)|hypoxia]].
| |
| * [[Fatigue]] may be present due to the work of breathing and [[hypoxia]].
| |
|
| |
| ===Physical Examination===
| |
| ====Vitals====
| |
| * [[Hypotension]] may be present due to a decrease in [[cardiac output]].
| |
| * [[Tachycardia]] with a rapid, weak, thready rapid pulse is present.
| |
|
| |
| ====Neck====
| |
| * Distended [[jugular vein]]s due to increased [[jugular venous pressure]].
| |
| ====Skin====
| |
| * [[Cyanosis]], cool, clammy, and mottled skin ([[cutis marmorata]]), due to vasoconstriction and subsequent hypoperfusion of the skin are often present.
| |
|
| |
| ====Lungs====
| |
| * Rapid and deep respirations (hyperventilation) due to sympathetic nervous system stimulation by stretch receptors and as compensation for [[metabolic acidosis]].
| |
|
| |
| * [[Pulmonary Edema]] (fluid in the lungs) due to insufficient pumping of the heart, fluid backs up into the lungs.
| |
|
| |
| ====Genitourinary====
| |
| * [[Oliguria]] (low urine output) due insufficient renal perfusion is present if the condition persists.
| |
|
| |
| === Electrocardiogram ===
| |
| An [[ECG|electrocardiogram]] may be useful in distinguishing cardiogenic shock from [[septic shock]] or [[neurogenic shock]]. A diagnosis of cardiogenic shock is suggested by the presence of [[ST segment changes]], new [[left bundle branch block]] or signs of a [[cardiomyopathy]]. [[Cardiac arrhythmia]]s may also be present.
| |
|
| |
| === Radiology ===
| |
| The [[chest x ray]] will show [[pulmonary edema]] in patients with [[left ventricular failure]]. In contrast, a [[pneumonia]] may be present in the patient with [[septic shock]].
| |
|
| |
| The heart may be enlarged ([[cardiomegaly]]) in the patient with [[tamponade]]. A [[widened mediastinum]] may be present in the patient with [[aortic dissection]].
| |
|
| |
| ===Echocardiography===
| |
| [[Echocardiography]] is important imaging modality in the evaluation of the patient with cardiogenic shock. It allows the clinician to distinguish cardiogenic shock from [[septic shock]] and [[neurogenic shock]]. In cardiogenic shock due to acute MI, poor wall motion will be present. Mechanical compliations such as papillary muscle rupture, pseudoaneurysm, and a ventricular septal defect may also be visualized. [[Valvular heart disease]] such as [[aortic stenosis]], [[aortic insufficiency]] and [[mitral stenosis]] can also be assessed. Dynaimc outflow obstruction such as {HOCM]] can also be indetified and quatified. The left ventricular fucntion in patients with cardiomyopathy can be evaluated.
| |
|
| |
| === Swan-ganz catheter ===
| |
| The [[Swan-ganz catheter]] or Pulmonary artery catheter may assist in the diagnosis by providing information on the hemodynamics.
| |
|
| |
| === Biopsy ===
| |
| In case of suspected cardiomyopathy a [[biopsy]] of heart muscle may be needed to make a definite [[diagnosis]].
| |
|
| |
| == Treatment ==
| |
| The goal of managing the patient with cardiogenic shock is to optimize the filling of the left ventricle so that the [[Starling relationship]] and mechanical performance and contractility of the heart is optimized. In the setting of [[acute MI]], a [[pulmonary capillary wedge pressure]] of 18 to 20 mm Hg may optimize left ventricular filling. Filling pressures higher than this may lead to LV dilation, and poorer left ventricular function. If hypotension persists in the presence of adequate left ventricular filling pressures, then the addition of positive [[inotrope|inotropic agents]] to imporve contractility may be required. In the setting of acute MI, the placement of an [[intra-aortic balloon pump]] (which reduces [[afterload|workload]] for the heart, and improves perfusion of the [[coronary arteries]]) should be considered. In the setting of pronounced [[hypotension]], placement of a left [[ventricular assist device]] (which augments the pump-function of the heart) should be considered.
| |
|
| |
| ==Complications==
| |
| Complications of cardiogenic shock include:
| |
| ===Cardiac===
| |
| A downward spiral of hypotension leading to reduced coronary perfusion leading to further hypotension and a further reduction in coronary perfusion
| |
| ===Neurologic===
| |
| Coma
| |
| ===Renal===
| |
| Oligurin [[renal failure]]
| |
| ===Pulmonary===
| |
| Cardiogenic [[pulmonary edema]]
| |
|
| |
| ==Prognosis==
| |
| Cardiogenic shock carries a very poor prognosis, particularly in the elderly.
| |
|
| |
| == See also ==
| |
| * [[Intra-aortic balloon pump]] | | * [[Intra-aortic balloon pump]] |
| * [[Ventricular assist device]] | | * [[Ventricular assist device]] |
|
| |
| == Sources ==
| |
| *Irwin, R.S., Rippe, J.M., Curley, F.J., Heard, S.O. (1997) Procedures and Techniques in Intensive Care Medicine (3rd edition). Boston: Lippincott, Williams and Wilkins.
| |
| *Marino, P. (1997) The ICU Book. (2nd edition). Philadelphia: Lippincott, Williams and Wilkins.
| |
|
| |
| ==References==
| |
| {{reflist|2}}
| |
|
| |
| == External links ==
| |
| * [http://www.emedicine.com/med/topic285.htm Cardiogenic Shock] by [[eMedicine]]
| |
| {{Symptoms and signs}}
| |
| {{Intensive care medicine}}
| |
| {{SIB}}
| |
|
| |
|
| [[Category:Cardiology]] | | [[Category:Cardiology]] |
| [[Category:Cardiovascular diseases]] | | [[Category:Cardiovascular diseases]] |
| | [[Category:Emergency medicine]] |
| | [[Category:Intensive care medicine]] |
| [[Category:Medical emergencies]] | | [[Category:Medical emergencies]] |
| [[Category:Intensive care medicine]]
| |
| [[Category:Emergency medicine]]
| |
|
| |
| [[de:Kreislaufstillstand]]
| |
| [[es:Parada cardiorrespiratoria]]
| |
| [[fr:Arrêt cardio-circulatoire]]
| |
| [[id:Gagal jantung]]
| |
| [[he:דום לב]]
| |
| [[nl:Hartstilstand]]
| |
| [[ja:心停止]]
| |
| [[pl:Asystolia]]
| |
| [[pt:Choque cardiogênico]]
| |
| [[sr:Кардиогени шок]]
| |
| {{WikiDoc Help Menu}}
| |
| {{WikiDoc Sources}}
| |
