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| [[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]] | | | [[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]] | |
| [[Cardiogenic shock echocardiography or ultrasound|Echocardiography or Ultrasound]] | [[Cardiogenic shock other imaging findings|Other Imaging Findings]] | [[Cardiogenic shock other diagnostic studies|Other Diagnostic Studies]] | | [[Cardiogenic shock echocardiography or ultrasound|Echocardiography or Ultrasound]] | [[Cardiogenic shock other imaging findings|Other Imaging Findings]] | [[Cardiogenic shock other diagnostic studies|Other Diagnostic Studies]] |
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| === Electrocardiogram ===
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| 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.
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| === Radiology ===
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| The [[chest x ray]] will show [[pulmonary edema]], pulmonary vascular redistribution, enlarged hila, Kerley's B lines, and bilateral [[pleural effusions]] in patients with [[left ventricular failure]]. In contrast, a [[pneumonia]] may be present in the patient with [[septic shock]].
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| The heart may be enlarged ([[cardiomegaly]]) in the patient with [[tamponade]]. A [[widened mediastinum]] may be present in the patient with [[aortic dissection]].
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| The chest x ray may also be useful in excluding a [[tension pneumothorax]] that may be associated with [[hypotension]]
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| ===Echocardiography===
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| [[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. In [[septic shock]], a hypercontractile ventricle may be present. Mechanical complications 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. Dynamic outflow obstruction such as [[HOCM]] can also be indentified and quantified. The magnitude of left ventricular dysfunction in patients with cardiomyopathy can be evaluated.
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| === Swan-ganz catheter ===
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| The [[Swan-ganz catheter]] or [[pulmonary artery catheter]] may be helpful in distinguishing cardiogenic shock from [[septic shock]] and in optimizing the patient's left ventricular filling pressures (see section on [[Cardiogenic shock#Treatment|Treatment below)]]. The presence of significant V waves (greatly exceeding the pulmonary [[capillary wedge pressure]]) on the [[pulmonary artery]] tracing suggests either acute [[mitral regurgitation]] or a [[ventricular septal defect]].
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| === Biopsy ===
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| In case of suspected cardiomyopathy a [[biopsy]] of heart muscle may be of benefit in establishing a definitive [[diagnosis]].
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| == Treatment == | | == Treatment == |
| ===Urgent revascularizaiton===
| | [[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]] |
| If the patient has an [[ST elevation myocardial infarction]], then [[primary angioplasty]] should be considered to restore flow to the culprit artery. Consideration should also be given to restoration of flow in the non-culprit territories in the setting of cardiogenic shock.
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| Administration of streptokinase therapy to patients with cardiogenic shock has not been associated with an improvement in survival.<ref name="pmid2868337">{{cite journal |author= |title=Effectiveness of intravenous thrombolytic treatment in acute myocardial infarction. Gruppo Italiano per lo Studio della Streptochinasi nell'Infarto Miocardico (GISSI) |journal=Lancet |volume=1 |issue=8478 |pages=397–402 |year=1986 |month=February |pmid=2868337 |doi= |url=}}</ref> These studies, however, oare older and are limited by the infrequent use of [[adjunctive PCI]]. If a patient is not deemed a candidate for [[primary angioplasty]], then consideration should be given to fibrinolyitc administration.
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| ===Volume management===
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| 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.
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| ===Pharmacologic hemodynamic support===
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| If hypotension persists despite adequate left ventricular filling pressures, then the addition of vasconstrictors and/or inotropes is suggested. Hemodynamic monitoring is essential to assure that a target [[mean arterial pressure]] ([[MAP]]) of 60 to 65 mmHg is acheived to maintain perfusion to vital organs (brain, kidney, heart).
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| ====Selection of a vasopressor or an inotrope====
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| =====Systolic blood pressure (SBP) > 80 mm Hg=====
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| [[Dobutamine]] may be preferable over [[dopamine]] at this blood pressure. Dopamine increase contractility and heart rate and thereby increases myocardial oxygen demand. [[Dobutamine]] reduces the [[systemic vascular resistance]] and may not increase oxygen demands as much as dopamine, and is preferable at this systolic blood pressure. [[Phosphodiesterase inhibitors]] ([[PDI]]s) such as [[milrinone]] and [[inamrinone]] (formerly known as [[amrinone]]) are not dependent upon the adrenoreceptor activity and patients may not develop tolerance, and they may be less likely to increase myocardial oxygen demands. However, the addition of a vasopressor is often required as these agents reduce [[preload]] and [[afterload]]. PDIs are more likely to be associated with [[tachyarrhythmias]] than [[dobutamine]].
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| =====Systolic blood pressure (SBP) < 80 mm Hg=====
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| At systolic blood pressures < 80 mm Hg dopamine should be initiated first. The patient may not tolerate the vasodilating effects of dobutamine at this blood pressure. The initial dose of dopamine is 5 to 10 mcg/kg/min.
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| If the dopamine at doses of 20 mcg/kg/min does not achieve a MAP of 60-65 mm Hg, then norepinephrine can be added at an initial dose of 0.5 mcg/kg/min which can then be titrated up to 3.3 mcg/kg/min. Norepinephrine is avoided as a first line agent because of its adverse impact upon renal perfusion.
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| If norepinephrine does not generate a MAP of 60 mm Hg, then epinephrine can be added. Epinephrine increases both the [[stroke volume]] and [[heart rate]], but is associated with [[lactic acidosis]]
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| ===Mechanical support===
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| ====Intra-aortic balloon placement====
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| 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.
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| A recent meta-analysis of randomized trial data, however, challenges this common practice and class 1B recommendation.<ref name="pmid19168529">{{cite journal |author=Sjauw KD, Engström AE, Vis MM, van der Schaaf RJ, Baan J, Koch KT, de Winter RJ, Piek JJ, Tijssen JG, Henriques JP |title=A systematic review and meta-analysis of intra-aortic balloon pump therapy in ST-elevation myocardial infarction: should we change the guidelines? |journal=European Heart Journal |volume=30 |issue=4 |pages=459–68 |year=2009 |month=February |pmid=19168529 |doi=10.1093/eurheartj/ehn602 |url=http://eurheartj.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=19168529}}</ref> In a meta-analysis of seven randomized trials enrolling 1009 patient, IABP placement in STEMI was not associated with an improvement in mortality or in left ventricular function but was associated with a higher rate of stroke and bleeding. When data from non-randomized cohort studies were evaluated in a meta-analysis (n=10,529 STEMI patients with cardiogenic shock), IABP placement was associated with an 18% relative risk reduction in 30 day mortality among patients treated with a fibrinolytic agent. This particular analysis is confounded by the fact that those patients in whom an [[IABP]] was placed underwent [[adjunctive percutaneous intervention]] (PCI) more frequently. In this non-randomized cohort analysis, [[IABP]] placement in patients undergoing [[primary angioplasty]] was associated with a 6% relative increase in mortality (p<0.0008). Thus, neither randomized nor observational data support IABP placement in the setting of [[primary PCI]] for cardiogenic shock, and careful consideration should be given to the risk of [[stroke]] and bleeding prior to [[IABP]] placement in this population.
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| ====Left ventricular assist device placement====
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| In the setting of pronounced [[hypotension]] despite medical therapy and IABP placement, placement of a left [[ventricular assist device]] (which augments the pump-function of the heart) should be considered. A ventricular assist device should only be placed in those patients in whom the cardiogenic shock is deemed to be reversible or if it is being used as a bridge option. <ref>Farrar DJ, Lawson JH, Litwak P, Cederwall G. Thoratec VAD system as a bridge to heart transplantation. J Heart Transplant. Jul-Aug 1990;9(4):415-22; discussion 422-3.</ref>
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| ====Coronary artery bypass graft (CABG) placement====
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| CABG in this setting is associated with high rates of mortality and morbidity and is generally not performed if primary angioplasty can be performed.
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| ===Mechanical ventilation===
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| [[Mechanical ventilation]] is often required in patients with cardiogenic shock to assure adequate oxygenation.
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| ==ACC/AHA Guidelines (DO NOT EDIT)<ref name="pmid15339869">{{cite journal |author=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, Alpert JS, Anderson JL, Faxon DP, Fuster V, Gibbons RJ, Gregoratos G, Halperin JL, Hiratzka LF, Hunt SA, Jacobs AK |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=Circulation |volume=110 |issue=9 |pages=e82–292 |year=2004 |month=August |pmid=15339869 |doi= |url=http://circ.ahajournals.org/cgi/pmidlookup?view=long&pmid=15339869}}</ref>==
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| {{cquote|
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| ===Class I===
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| 1. [[Intra-aortic balloon counterpulsation]] is recommended for [[STEMI]] patients when [[cardiogenic shock]] is not quickly reversed with pharmacological therapy. The [[IABP]] is a stabilizing measure for [[angiography]] and prompt [[revascularization]]. ''(Level of Evidence: B)''
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| 2. Intra-arterial monitoring is recommended for the management of [[STEMI]] patients with [[cardiogenic shock]]. ''(Level of Evidence: C)''
| | == Related Chapters == |
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| 3. Early [[revascularization]], either [[PCI]] or [[CABG]], is recommended for patients less than 75 years old with ST elevation or [[LBBB]] who develop shock within 36 hours of [[MI]] and who are suitable for [[revascularization]] that can be performed within 18 hours of shock unless further support is futile because of the patient’s wishes or contraindications/unsuitability for further invasive care. ''(Level of Evidence: A)''
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| 4. [[Fibrinolytic therapy]] should be administered to [[STEMI]] patients with [[cardiogenic shock]] who are unsuitable for further invasive care and do not have contraindications to [[fibrinolysis]]. ''(Level of Evidence: B)''
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| 5. [[Echocardiography]] should be used to evaluate mechanical complications unless these are assessed by invasive measures. ''(Level of Evidence: C)''
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| ===Class IIa=== | |
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| 1. Pulmonary artery catheter monitoring can be useful for the management of [[STEMI]] patients with [[cardiogenic shock]]. ''(Level of Evidence: C)''
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| 2. Early [[revascularization]], either [[PCI]] or [[CABG]], is reasonable for selected patients 75 years or older with ST elevation or [[LBBB]] who develop shock within 36 hours of [[MI]] and who are suitable for [[revascularization]] that can be performed within 18 hours of [[shock]]. Patients with good prior functional status who agree to invasive care may be selected for such an invasive strategy. ''(Level of Evidence: B)''}}
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| == See also ==
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| * [[Intra-aortic balloon pump]] | | * [[Intra-aortic balloon pump]] |
| * [[Ventricular assist device]] | | * [[Ventricular assist device]] |
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| *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. | | *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. | | *Marino, P. (1997) The ICU Book. (2nd edition). Philadelphia: Lippincott, Williams and Wilkins. |
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| ==References==
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| {{reflist|2}}
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| [[Category:Cardiology]] | | [[Category:Cardiology]] |