Lower noradrenaline-mediated mean arterial pressure target in patients with acute myocardial infarction-related cardiogenic shock: rationale and design of the NORshock study

Acute myocardial infarction-related cardiogenic shock (AMI-CS) is commonly clinically characterised by low blood pressure. Noradrenaline is the guideline-recommended first-line vasopressor therapy in patients in cardiogenic shock to increase blood pressure. Although no strict criteria exist, noradrenaline is commonly titrated to a mean arterial pressure (MAP) of above 65 mmHg. No evidence exists, however, that targeting a pharmacologically induced MAP of above 65 mmHg improves clinical outcome. Furthermore, noradrenaline is associated with unwanted effects such as elevated afterload, increased myocardial oxygen demand, and arrhythmias. Therefore, we sought to investigate whether treatment with a lower noradrenaline-mediated MAP-target regimen in AMI-CS patients leads to improved outcomes. In this international, open-label, multicentre, randomised superiority trial, 776 patients will be allocated in a 1:1 ratio to either the index treatment of a lower noradrenaline-mediated MAP-target regimen (MAP of 55 mmHg) or a standard noradrenaline-mediated MAP-target regimen (MAP of at least 65 mmHg). The NORshock trial tests the hypothesis that a permissive hypotension treatment strategy with reduced use of noradrenaline in patients with AMI-CS is superior to standard care in terms of a combined endpoint of all-cause death and renal replacement therapy within 30 days. The NORshock trial is the first randomised trial investigating a strategy of a lower noradrenaline-mediated MAP-target regimen (MAP of 55 mmHg) compared with a standard noradrenaline-mediated MAP-target regimen (MAP of at least 65 mmHg) on clinical outcomes in AMI-CS patients.