Cardiogenic shock — structured written assessment

SAQ 1 (10 marks)

Practice scenario. A 62-year-old man presents to a PCI centre with an anterior ST-elevation MI. His blood pressure is 82/54 mmHg and heart rate 118 bpm; he is confused, cold and oliguric, and his arterial lactate is 4.6 mmol/L. Echocardiography shows severe LV systolic dysfunction with normal right ventricular function. He has had no cardiac arrest. Angiography shows an occluded left anterior descending artery (an identifiable culprit) and severe disease in the other two arteries.^[1][3]

1. How does ESC 2026 define cardiogenic shock, and what biochemical criterion does it require? (2)^[1]
2. Which SCAI stage is he in at presentation, and what separates this stage from stage B? (2)^[1][6]
3. Which coronary procedure do ESC 2023 and ACC/AHA 2025 recommend, and what should be done about the non-culprit arteries? (2)^[2][3]
4. Shock remains severe and refractory after PCI. Which mechanical support option do ESC 2026 and ACC/AHA 2025 support for him, with class and level? (2)^[1][3]
5. Which vasopressor does ESC 2026 prefer, with class and level, and what does it say about inotropes? (2)^[1]

Model answers — SAQ 1

1. ESC 2026 defines cardiogenic shock as a state of critical end-organ hypoperfusion caused by primary cardiac dysfunction, with no specific blood pressure cut-off (1 mark).^[1] It says the biochemical manifestation of inadequate tissue perfusion is best measured by arterial lactate, with a value above 2 mmol/L required; his is 4.6 mmol/L (1 mark).^[1]
2. Stage C (classic): hypoperfusion requiring intervention (inotrope, vasopressor or mechanical support), as printed in ESC 2026 Table 13 (1 mark).^[1] Stage B is haemodynamic instability without hypoperfusion; he has hypoperfusion (confusion, cold extremities, oliguria, lactate above 2 mmol/L), and SCAI 2022 lists lactate of 2 mmol/L or more as typical of stage C (1 mark).^[1][6]
3. ESC 2023: immediate coronary angiography and PCI of the infarct-related artery (if indicated) in cardiogenic shock complicating ACS (Class I, Level B); ACC/AHA 2025: in ACS with cardiogenic shock or haemodynamic instability, emergency revascularisation of the culprit vessel by PCI or with CABG is indicated to improve survival, irrespective of time from symptom onset (COR 1, LOE B-R) (1 mark).^[2][3] For multivessel disease in ACS presenting in cardiogenic shock, ESC 2023 recommends infarct-related-artery-only PCI during the index procedure (Class I, Level B), with staged PCI of the non-infarct arteries to be considered, based on ischaemia, symptoms, patient comorbidities and clinical condition (Class IIa, Level C); ACC/AHA 2025 says routine PCI of a non-infarct-related artery at the time of primary PCI should not be performed in ACS complicated by shock, because of the higher risk of death or renal failure (COR 3: Harm, LOE B-R) (1 mark).^[2][3]
4. ESC 2026: temporary MCS with a microaxial flow pump should be considered in selected patients with cardiogenic shock caused by ST-elevation MI with LV systolic dysfunction and no risk of hypoxic brain injury, to reduce the risk of death (Class IIa, Level B1); he has had no arrest and no resuscitation (1 mark).^[1] ACC/AHA 2025: in selected patients with STEMI and severe or refractory shock, a microaxial intravascular flow pump is reasonable to reduce death (COR 2a, LOE B-R); routine IABP or VA-ECMO is not recommended (COR 3: No benefit, LOE B-R) (1 mark).^[3]
5. ESC 2026: vasopressors, preferably norepinephrine, may be considered in cardiogenic shock to increase blood pressure and vital organ perfusion (Class IIb, Level C) (1 mark).^[1] Inotropes may be considered with systolic blood pressure below 90 mmHg and hypoperfusion not responding to standard treatment, including fluid challenge, to improve perfusion (Class IIb, Level C), and are not routinely recommended because of the risks of arrhythmia and myocardial ischaemia (1 mark).^[1]

SAQ 2 (10 marks)

Practice scenario. A 54-year-old woman with known HFrEF, taking bisoprolol, is admitted to a regional hospital with decompensated heart failure. Her systolic blood pressure is 86 mmHg, she is cold and confused, her urine output is low and her lactate is 3.4 mmol/L. She has not responded to standard treatment, including a fluid challenge. There is no acute coronary syndrome.^[1]

1. Compare the ESC 2026 and 2022 AHA/ACC/HFSA rows on inotropes, with class and level. (2)^[1][4]
2. Which inotrope does ESC 2026 suggest may be preferred in her, and what infusion rate does its supplementary table give for that drug? (2)^[1]
3. What does the 2022 AHA/ACC/HFSA guideline say about a pulmonary artery catheter, with class and level? (2)^[4]
4. She fails to respond to initial measures. What do the 2022 AHA/ACC/HFSA rows say about where she should be managed and by whom? (2)^[4]
5. What does ESC 2026 recommend about a Shock Team and about temporary MCS in HF-related haemodynamic instability? (2)^[1]

Model answers — SAQ 2

1. ESC 2026 (Recommendation Table 9, decompensated heart failure): inotropic agents may be considered with systolic blood pressure below 90 mmHg and evidence of hypoperfusion not responding to standard treatment, including fluid challenge, to improve perfusion (Class IIb, Level C) (1 mark).^[1] 2022 AHA/ACC/HFSA: in cardiogenic shock, intravenous inotropic support should be used to maintain systemic perfusion and preserve end-organ performance (COR 1, LOE B-NR) (1 mark).^[4]
2. Because she takes a beta-blocker, ESC 2026 says levosimendan or a phosphodiesterase-III inhibitor may be preferred over dobutamine on the basis of mode of action, although no relevant RCTs of levosimendan in shock are available (1 mark).^[1] Supplementary Table S15: levosimendan standard 0.1 μg/kg/min, adjusted to 0.05 or 0.2 μg/kg/min on blood pressure and response, with no bolus; milrinone 0.375–0.75 μg/kg/min (1 mark).^[1]
3. Placement of a PA line may be considered to define haemodynamic subsets and appropriate management strategies (COR 2b, LOE B-NR) (1 mark).^[4] Its supportive text says that if time allows, escalation to MCS should be guided by invasive haemodynamics, and that a PA catheter may be useful when the cause of hypotension or end-organ dysfunction is uncertain, particularly when shock is not responding to empiric initial measures (1 mark).^[4]
4. For patients not rapidly responding to initial shock measures, triage to centres that can provide temporary MCS may be considered to optimise management (COR 2b, LOE C-LD) (1 mark).^[4] In cardiogenic shock, management by a multidisciplinary team experienced in shock is reasonable (COR 2a, LOE B-NR) (1 mark).^[4]
5. A multidisciplinary Shock Team is recommended in potential candidates for temporary MCS, to guide device selection (modality and type) based on patient and HF characteristics (Class I, Level C) (1 mark).^[1] Temporary MCS should be considered in selected patients with HF-related haemodynamic instability as a bridge to recovery, decision, bridge, candidacy or transplantation (BTR, BTD, BTB, BTC or BTT) (Class IIa, Level C) (1 mark).^[1]