Cardiogenic shock patients are brought to the emergency room presenting with a spectrum of signs and symptoms that represents a different phase of the clinical condition, from inciting event to end stage organ failure.

The following system wise presentation of signs and symptoms are commonly seen in cardiogenic shock and its inciting events:

• General Appearance: Patients in shock usually appears ashen or cyanotic because of the progressive hypoperfussion state of the tissues. 
• Integumentary: The skin will appear cold to touch because of peripheral tissue hypoperfusion. 
• Head and Neck: Jugular venous distention may be evident due to the increased a cardiac compliance. 
• Chest and heart: Complains of chest heaviness of pain may herald the inciting event of MI. Heart sounds will appear distant and fast (tachycardia) upon auscultation due to cardiac tamponade or overload. The presence of the 3rd and 4th heart sounds due to valvular dysfunction may also be heard. Heavy breathing may also ensue as a compensatory mechanism to overcome the hypoxemia. 
• Abdomen: The urine output will be low because of renal hypoperfusion during shock.
• Extremities: The peripheral pulses will appear rapid or faint due to the drop of blood pressure. Irregular pulses may also be felt with arrhythmias. 
• Neurologic: Patients may also present with altered mental status due the brain’s hypoxic states.

• Hypothermia

  V-A ECMO is an effective and recognized method of treatment of patients in cardiogenic shock and deep hypothermia. [ncbi.nlm.nih.gov]

  Moderate hypothermia may improve parameters of cardiac function. [ 12 ] Prognosis Cardiogenic shock is the leading cause of death in acute MI. [patient.info]

  Bernard SA, Gray TW, Buist MD (2002) Treatment for comatose survivors of out-of-hospital cardiac arrest with induced hypothermia. N Engl J Med 346: 557–563 CrossRef PubMed Google Scholar 32. [link.springer.com]

• Acutely Ill Patient

  Results of the Sepsis Occurrence in Acutely Ill Patients (SOAP) Study. Crit Care Med 2006; 34: 589–97. CrossRef MEDLINE 16. [dx.doi.org]

  Results of the Sepsis Occurrence in Acutely Ill Patients (SOAP) Study. Crit Care Med. 2006; 34 :589–597. [ PubMed ] [ Google Scholar ] 16. Fuhrmann JT, Schmeisser A, Schulze MR, et al. [oadoi.org]

• Pallor

  Decreased cardiac output worsens hypoperfusion and acidemia This process spirals creating a vicious cycle: Signs + Symptoms: Shortness of breath Dyspnea on exertion Diaphoresis Cough with pink sputum Chest pain Air hunger Hypoxia Tachycardia JVD Rales Skin pallor [rebelem.com]

  Signs and symptoms of hypotension are present: Weak or absent peripheral pulses; mottled extremities from low flow states; diaphoresis; and pallor. Patients may be restless with changes in level of consciousness. [cathlabdigest.com]

• Unconsciousness

  […] shock ( T81.1- ) psychogenic syncope ( F48.8 ) shock NOS ( R57.9 ) shock complicating or following abortion or ectopic or molar pregnancy ( O00 - O07, O08.3 ) shock complicating or following labor and delivery ( O75.1 ) Stokes-Adams attack ( I45.9 ) unconsciousness [icd10data.com]

  These include cold and pale skin, reduced or a lack of urine output and signs of impaired cerebral function like dizziness or even unconsciousness. [cochrane.org]

• Dyspnea

  A 77-year-old man presented with exercise intolerance and progressive exertional dyspnea and chest pain. The patient was suffered from cardiogenic shock after percutaneous coronary intervention. [ncbi.nlm.nih.gov]

• Rales

   Bilateral Diffuse rales upon pulmonary exam.  ABG shows- alkalosis with hypocapnia 4. A Case 5. CXR 6. DEFINITION  Persistent and marked hypotension(>30 minutes) with systolic arterial pressure 7. Differentiating Types of Shock 8. [slideshare.net]

  […] output Decreased cardiac output worsens hypoperfusion and acidemia This process spirals creating a vicious cycle: Signs + Symptoms: Shortness of breath Dyspnea on exertion Diaphoresis Cough with pink sputum Chest pain Air hunger Hypoxia Tachycardia JVD Rales [rebelem.com]

  In fact, the presence of elevated JVP > 8 cmH 2 O and rales more than one-third of the lung bases predicted CS with very high sensitivity and specificity [ 14 ]. [intechopen.com]

  Approximately two thirds of patients will develop pulmonary congestion manifested as rales on pulmonary examination. [emedicine.medscape.com]

  Study; CAPRICORN, CArvedilol Post infaRct SurvIval COntRol in LV dysfunctioN; VALIANT, VALsartan In Acute myocardial iNfarcTion; DINAMIT, Defibrillator IN Acute Myocardial InfarcTion; MADIT II, Multicenter Automatic Defibrillator Implantation Trial II; RALES [circ.ahajournals.org]

• Tachypnea

  Other signs or symptoms include dyspnea, tachycardia, cyanosis, peripheral edema, altered mental status, tachypnea and reduced urine output. [emsworld.com]

• Nausea

  The possible complications of lithium overdose include altered mental status, hand tremor, muscle weakness, nausea, vomiting, diarrhea, seizure, syncope, and arrhythmia. [ncbi.nlm.nih.gov]

  Symptoms As many patients with cardiogenic shock have had an acute MI, symptoms can include: Chest pain Nausea and vomiting Dyspnoea Profuse sweating Confusion/disorientation Palpitations Faintness/syncope Signs Pale, mottled, cold skin with slow capillary [patient.info]

  A Case  A 72 yrs old male is brought to the ED with sudden onset chest pain,diaphoresis, nausea and dyspnoea  No other medical history is known.  Is agitated upon presentation and is unable to give any history. 3. [slideshare.net]

  Patients also may report associated autonomic symptoms, including nausea, vomiting, and sweating. A history of previous cardiac disease, use of cocaine, previous MI, or previous cardiac surgery should be obtained. [emedicine.medscape.com]

  Other MI symptoms include shortness of breath, nausea, anxiety, and a sense of impending doom. The patient may also have a history of symptoms of any of the other etiologies mentioned above. [medical-dictionary.thefreedictionary.com]

• Vomiting

  The possible complications of lithium overdose include altered mental status, hand tremor, muscle weakness, nausea, vomiting, diarrhea, seizure, syncope, and arrhythmia. [ncbi.nlm.nih.gov]

  Hypovolemic shock result of intravascular blood volume depletion common causes: haemorrhage vomiting diarrhoea dehydration third-space losses during major operations primary abnormality is a decrease in preload. [aic.cuhk.edu.hk]

  Symptoms As many patients with cardiogenic shock have had an acute MI, symptoms can include: Chest pain Nausea and vomiting Dyspnoea Profuse sweating Confusion/disorientation Palpitations Faintness/syncope Signs Pale, mottled, cold skin with slow capillary [patient.info]

  Patients also may report associated autonomic symptoms, including nausea, vomiting, and sweating. A history of previous cardiac disease, use of cocaine, previous MI, or previous cardiac surgery should be obtained. [emedicine.medscape.com]

  See also toxemic shock. shock gut animals in shock develop changes in the gut including congestion and hemorrhage into the lumen. hypovolemic shock shock due to reduced blood volume as a result of water deprivation, fluid loss due to diarrhea, vomiting [medical-dictionary.thefreedictionary.com]

• Hypotension

  The patient will remain hypotensive until an inotrope like dobutamine is initiated. If unsafe medications are chosen for intubation, the patient will have a VT arrest. [emsimcases.com]

  These vasodilator effects may cause hypotensive episodes to develop and careful titration is needed. A loading dose may be given for both inamrinone and milrinone. [cathlabdigest.com]

  The characteristic features are: poor tissue perfusion: poor cerebral function cool extremeties oliguria hypotension poor cardiac output Cardiogenic shock is most commonly caused by myocardial infarction. Mortality approaches 90%. [gpnotebook.co.uk]

  Fluid resuscitation may improve the patient�s cardiac output and hypotension temporarily and buy time for definitive intervention. � Gavin Joynt April 2003 [aic.cuhk.edu.hk]

  One of the life-threatening complications of STEMI is cardiogenic shock during which hypotension is present from low cardiac output. This results in end-organ hypoperfusion and potentially multi-system organ failure and can be fatal. [healio.com]

• Tachycardia

  After admission, the patient had four cardiac arrests (three episodes of pulseless ventricular tachycardia/ventricular fibrillation and one episode of asystole) over the next few hours. [ncbi.nlm.nih.gov]

  Inotropy,vasodilation,tachycardia,hypotensio n, arrythmia EPINEPHRINE 0.05-0.5mcg/kg/min Vasoconstriction,inotropy,tachycardia,hypote nsion VASOPRESSIN 0.1-0.4 units/min LEVOSIMENDAN 12mcg 0.2 Mcg/kg.min Vasodilation,inotropy,tachycardia,hypotensio n [slideshare.net]

  Compensatory mechanisms of tachycardia and increased SVR are typically noted. [cathlabdigest.com]

• Heart Disease

  After successful ECMO treatment, the one year survival rate of patients with ischemic heart disease was 73.7 %, and the one year survival for patients with non-ischemic heart disease was 75%. [ncbi.nlm.nih.gov]

  […] and Heart Failure, Cardiac Surgery and VHD, Congenital Heart Disease, CHD and Pediatrics and Arrhythmias, CHD and Pediatrics and Imaging, CHD and Pediatrics and Interventions, CHD and Pediatrics and Prevention, Acute Heart Failure, Interventions and ACS [acc.org]

  You may reduce the risk of developing cardiogenic shock by: Quickly treating its cause (such as heart attack or heart valve problem) Preventing and treating the risk factors for heart disease, such as diabetes, high blood pressure, high cholesterol and [nlm.nih.gov]

• Cyanosis

  Cyanosis. Cyanosis occurs because there is insufficient oxygenated blood that is being distributed to all body systems. Assessment and Diagnostic Findings Diagnosis of cardiogenic shock may include the following diagnostic tests: Auscultation. [nurseslabs.com]

  Physical examination Most common symptoms are hypotension in the absence of hypovolemia, oliguria, cyanosis, cool extremities, and reduced mental status. [medical-dictionary.thefreedictionary.com]

  Tissue hypoxemia is clinical seen as cyanosis, oliguria, altered sensorium and cool extremities. Definition Cardiogenic shock is a medical condition wherein the heart is no longer capable to pump effectively and preserve adequate tissue perfusion. [symptoma.com]

  The diagnosis of cardiogenic shock sometimes can be made at the bedside by observing hypotension and clinical signs of poor tissue perfusion, including oliguria, cyanosis, cool extremities, and altered mentation. [www1.cgmh.org.tw]

  Other signs or symptoms include dyspnea, tachycardia, cyanosis, peripheral edema, altered mental status, tachypnea and reduced urine output. [emsworld.com]

• Jugular Venous Distention

  Head and Neck: Jugular venous distention may be evident due to the increased a cardiac compliance. Chest and heart: Complains of chest heaviness of pain may herald the inciting event of MI. [symptoma.com]

  venous distention and crackles in the lungs are usually (but not always) present; peripheral edema also may be present. [emedicine.medscape.com]

  When the patient has entered the compensatory stage, symptoms may include an altered level of consciousness; sinus tachycardia; the presence of an S3 or S4 gallop rhythm; jugular venous distention; hypotension; rapid, deep respirations; pulmonary crackles [medical-dictionary.thefreedictionary.com]

  venous distention and crackles in the lungs are usually (but not always) present; peripheral edema also may be present Heart sounds are usually distant, and third and fourth heart sounds may be present The pulse pressure may be low, and patients are [emedicine.com]

• Cold, Clammy Skin

  clammy skin; and decreased bowel sounds. [medical-dictionary.thefreedictionary.com]

  clammy skin Oliguria Echocardiographic findings such as LV ejection fraction (LVEF) and mitral regurgitation are independent predictors of mortality. [emedicine.com]

• Anuria

  The patient becomes mentally unresponsive; hypotension becomes worse, requiring high doses of positive inotropic agents; metabolic and respiratory acidosis become apparent; oliguria or anuria and anasarca may ensue; and symptoms of DIC may be present. [medical-dictionary.thefreedictionary.com]

• Cesarean Section

  Herein, we report a rare case of a life-threatening "secondary" TTC in a patient with post-cesarean section severe hemorrhage, and we point out that early co-administration of esmolol and levosimendan might be an effective and safe therapeutic approach [ncbi.nlm.nih.gov]

• Altered Mental Status

  The possible complications of lithium overdose include altered mental status, hand tremor, muscle weakness, nausea, vomiting, diarrhea, seizure, syncope, and arrhythmia. [ncbi.nlm.nih.gov]

  Mental Status Decreased Urine Output Immediate Management: As STEMI is the most common cause of cardiogenic shock, we will focus on the management of this disorder. [rebelem.com]

  Neurologic: Patients may also present with altered mental status due the brain’s hypoxic states. Cardiogenic shock often presents as an emergency and they are diagnosed clinically by their characteristic sign and symptoms. [symptoma.com]

  Decline in higher cortical function may indicate diminished perfusion of the brain, which leads to an altered mental status ranging from confusion and agitation to flaccid coma. The heart plays a central role in perpetuating shock. [www1.cgmh.org.tw]

  Other signs or symptoms include dyspnea, tachycardia, cyanosis, peripheral edema, altered mental status, tachypnea and reduced urine output. [emsworld.com]

• Confusion

  Symptoms include: Chest pain or pressure Coma Decreased urination Fast breathing Fast pulse Heavy sweating, moist skin Lightheadedness Loss of alertness and ability to concentrate Restlessness, agitation, confusion Shortness of breath Skin that feels [nlm.nih.gov]

  Mental confusion. Insufficient oxygenated blood in the brain could gradually cause mental confusion and obtundation. Cyanosis. Cyanosis occurs because there is insufficient oxygenated blood that is being distributed to all body systems. [nurseslabs.com]

  Symptoms may include the following: confusion and anxiety sweating and cold extremities (fingers and toes) rapid but weak heart beat (tachycardia) low or absent urinary output (oliguria) fatigue due to hyperventilation sudden shortness of breath coma, [healthline.com]

  Symptoms Symptoms include: Chest pain or pressure Coma Decreased urination Fast breathing Fast pulse Heavy sweating, moist skin Lightheadedness Loss of alertness and ability to concentrate Restlessness, agitation, confusion Shortness of breath Skin that [mountsinai.org]

• Lethargy

  In the acute setting, this will typically manifest as a change in mental status (lethargy, decreased responsiveness, agitation, decreased cap refill, cool extremeties etc.). [rebelem.com]

  In the acute setting, this will typically manifest as a change in mental status (lethargy, decreased responsiveness, agitation etc.). Although cardiogenic shock is not common, it does complicate 7-10% of patients with STEMI and 3% of NSTEMIs. [emdocs.net]

• Clonus

  Seizure, clonus, and nonreactive mydriasis were present during 4 days, and complete awakening was delayed to day 15. [ncbi.nlm.nih.gov]

Cardiogenic shock often presents as an emergency and they are diagnosed clinically by their characteristic sign and symptoms. The following diagnostic tests are also performed with patients suffering of cardiogenic shock:

• Blood Pressure Monitoring: Patients in frank shock will present with very low blood pressure reading. 
• Electrocardiogram (ECG): This test makes use of electrodes that are attached to the chest to determine the electrical activity of the heart. Ischemic heart muscle does not conduct electrical impulse thus acute heart attacks can be diagnosed using this test.
• Chest X-ray: Imaging will reveal the size of the heart and its vessels. This will also show lung congestion in patients with heart attacks.
• Blood tests: This tests will evaluate the kidneys and the liver status of the patient. This can also check for possible infections of the heart. Arterial blood gas can demonstrate acidosis and hypoxemia states.
• Echocardiogram: This imaging modality makes use of sound waves to scan the heart walls and point out which part of the heart wall is no longer pumping.
• Coronary angiogram (catheterization) – This is an invasive technique that makes use of a long slender tube inserted in the femoral arteries where a dye is injected to exactly show which cardiac artery is blocked during the attack. Cardiac catheterization can be used to repair the vessel using inset balloons or mesh in a procedure called angioplasty. 

• Cardiac Output Decreased

  cardiac output Decreased cardiac output worsens hypoperfusion and acidemia This process spirals creating a vicious cycle: Signs + Symptoms: Shortness of breath Dyspnea on exertion Diaphoresis Cough with pink sputum Chest pain Air hunger Hypoxia Tachycardia [rebelem.com]

  The clinical definition of cardiogenic shock is a decreased cardiac output and evidence of tissue hypoxia in the presence of adequate intravascular volume. [www1.cgmh.org.tw]

  When cardiac output decreases, the body responds with compensatory mechanisms. [cathlabdigest.com]

• Lactate Decreased

  RESULTS: At 24 h, lactate decreased from 3.2 (2.1-6.8) to 1.8 (1.2-2.2) mmol/L (p < 0.001). [ncbi.nlm.nih.gov]

Patients in cardiogenic shock usually come in the emergency room illegible for advanced life support like ventilators, continuous oxygenation and intravenous access for medications. Some patients may require medications to increase blood flow through the heart and improve the heart pump muscles. The following medications are usually used in cardiogenic shock and heart attacks:

• Aspirin
• Thrombolytic
• Anti-platelets
• Anti-coagulants
• Inotropic agents
• Beta-blockers and renin-angiotensin-aldosterone inhibitors [7]

Invasive medical approach to cardiogenic shock includes: Angioplasty, stenting, and balloon pumps [8]. Where medical approach are futile, the following cardiovascular procedures may be done in cardiogenic shock:

•  Coronary Artery Bypass Graft (CABG) surgery [9]
•  Surgical repair of the heart
•  Heart pumps – Ventricular assist devices (VAD) [10]
•  Heart transplant

The mortality rate of patients with cardiogenic shock among myocardial infarction patients is very high and despite expert medical care at 50-60% [4].

The key to the survival of cardiogenic shock patients in ischemia or infarction of the heart is the rapid identification of the clinical disease, prompt fluid resuscitation, and immediate coronary artery revascularization [5]. The demonstration of a right ventricular dilatation and infarction by voltage in an electrocardiogram confers a poor outcome among patients [6].

Complications

When cardiogenic shock is left unmitigated, the following complications may arise as a result:

• Liver damage
• Kidney failure
• Brain damage
• Cardiac damage
• Cardio-pulmonary arrest
• Cardiac dysrhythmia
• Ventricular aneurysm
• Thromboembolic problems
• Death

Cardiogenic shock occurs when the heart becomes dysfunctional and is unable to keep up with the body’s needs. The most common causes are serious cardiac complications that occur during a myocardial infarction, the most common etiology includes:

• Cardiac standstill where a large section of the cardiac wall is unable to move
• Cardiac rupture due to increased myocardial damage
• Heart dysrhythmias like ventricular tachycardia and ventricular fibrillation
• Pericardial tamponade
• Cardiac valve prolapse
• Cardiac septal tear
• Symptomatic bradycardia 
• Systolic dysfunction
• Diastolic dysfunction
• Coronary artery disease
• Acute coronary syndromes due to beta-blockers and angiotensin-converting enzyme inhibitors [2] 

In the United States, the incidence of cardiogenic shock among heart attack patients ranges from 5% to 10%. Although, a community-wide analysis done in the Worcester Heart Attack study conveyed an average of 7.5% incidence of cardiogenic shock during heart attacks [3].

In ST-elevation myocardial infarction (STEMI), cardiogenic shock occurs in 8.6% of patients. In Europe, relative incidence of cardiogenic shock averages at 7% among MI cases. The Hispanic race has the highest mortality rate for cardiogenic shock reaching a 74% level. There is a male predisposition of cardiogenic shock mortality of up to 58%.

Cardiogenic shock represents an acute deterioration of the heart pump muscle affecting up to 40% of the left ventricular muscle function. Heart conditions that leads to this state includes myocardial infarction, myocardial ischemia, advanced cardiomyopathy, acute myocarditis, uncontrolled arrhythmia, and valvular dysfunction.

The cardiac muscle pathophysiology is based on the hypoperfusion state of the heart muscle causing an increased cardiac demand but poor cardiac output. This vicious cycle pattern leads to cardiogenic shock and gives rise to its characteristic symptoms. The prolonged tissue hypoperfusion will lead to anaerobic glycolysis and the accumulation of lactic acid which results in intracellular acidosis.

The acidotic state will breakdown the lysosomes and cause myonecrosis of the heart muscles at the site of ischemia or infarction. In some cases of myocardial hypoperfusion, the heart muscle becomes stunned or hibernates into a reversible state of functionality where it may resume to function normally after adequate revascularization to the heart muscle happens.

The dysfunctional left ventricle in the myocardial infarction or ischemia will increase its diastolic filling end-pressure, the diminished state of cardiac compliance will lead to the accumulation of the blood in the lungs and presents with pulmonary congestion. The diminished blood flow to the brain may lead to cortical signs of confusion, altered state of sensorium, agitation and flaccid coma.

The most effective way to prevent the occurrence of a cardiogenic shock is to directly prevent the occurrence of a heart attack that causes it. The following lifestyle modifications are done to prevent a heart attack:

• Active control of hypertension
• Watch your weight
• Quit smoking
• Regular cardio exercises
• Healthy eating
• Lower daily stress

Cardiogenic shock is a clinical condition where the heart as a pump is no longer able to perfuse the tissues adequately which causes significant hypoxia in the presence of adequate blood volume. Cardiogenic shock is the most common cause of death in acute myocardial infarction (MI) despite advances in medical care [1].

Cardiogenic shock is considered as a rare and fatal physiologic state caused by heart dysfunction at systole. There is usually a sustained form of hypotension occurring below 90 mmHg for at least 30 minutes, a reduced cardiac index of less than 2.2 l/min/m2, and increase in capillary wedge pressure of more than 15 mmHg. Tissue hypoxemia is clinical seen as cyanosis, oliguria, altered sensorium and cool extremities.

Definition

Cardiogenic shock is a medical condition wherein the heart is no longer capable to pump effectively and preserve adequate tissue perfusion.

Cause

Cardiac standstill, cardiac rupture, tamponade, dysrhythmias, Valvular diseases, and ventricular septal defects may cause cardiogenic shock.

Symptoms

Patients may appear with altered mental state, blue or purple coloration of the skin or mucous membranes, chest pain, low output of urine and thread-like pulses. 

Diagnosis

History and physical examination is the mainstay in emergency diagnosis. This may be augmented with ECG, Chest X-ray and Echocardiogram.

Treatment and follow-up

Advanced cardiac life support, blood thinning medications, inotropic agents. Surgical options include coronary artery by-pass surgery and heart transplant surgery.

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2. Al-Reesi A, Al-Zadjali N, Perry J, Fergusson D, Al-Shamsi M, Al-Thagafi M, et al. Do beta-blockers reduce short-term mortality following acute myocardial infarction? A systematic review and meta-analysis. CJEM. May 2008; 10(3):215-23.
3. Goldberg RJ, Samad NA, Yarzebski J, Gurwitz J, Bigelow C, Gore JM. Temporal trends in cardiogenic shock complicating acute myocardial infarction. N Engl J Med. Apr 15 1999; 340(15):1162-8.
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5. Babaev A, Frederick PD, Pasta DJ, Every N, Sichrovsky T, Hochman JS. Trends in management and outcomes of patients with acute myocardial infarction complicated by cardiogenic shock. JAMA. Jul 27 2005; 294(4):448-54
6. Hamon M, Agostini D, Le Page O, Riddell JW, Hamon M. Prognostic impact of right ventricular involvement in patients with acute myocardial infarction: meta-analysis. Crit Care Med. Jul 2008; 36(7):2023-33.
7. van Diepen S, Reynolds HR, Stebbins A, Lopes RD, Džavík V, Ruzyllo W, Geppert A, Widimsky P, Ohman EM. Incidence and outcomes associated with early heart failure pharmacotherapy in patients with ongoing cardiogenic shock. Crit Care Med. 2014; 42(2):281-8 (ISSN: 1530-0293)
8. Thiele H, Schuler G, Neumann FJ, Hausleiter J, Olbrich HG, Schwarz B, Hennersdorf M, Empen K, Fuernau G. Intraaortic balloon counterpulsation in acute myocardial infarction complicated by cardiogenic shock: design and rationale of the Intraaortic Balloon Pump in Cardiogenic Shock II (IABP-SHOCK II) trial. Am Heart J. 2012; 163(6):938-45 (ISSN: 1097-6744)
9. Hochman JS, Sleeper LA, White HD, Dzavik V, Wong SC, Menon V, et al. One-year survival following early revascularization for cardiogenic shock. JAMA. Jan 10 2001; 285(2):190-2.
10. Basra SS, Loyalka P, Kar B. Current status of percutaneous ventricular assist devices for cardiogenic shock. Curr Opin Cardiol. 2011; 26(6):548-54 (ISSN: 1531-7080)