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When a patient dies it is of considerable consolation to relatives if they can be reassured that everything possible and appropriate was done. For many acute heart failure patients in the UK, this approach cannot be taken with honesty. This is because the NHS will not fund circulatory support equipment to treat cardiogenic shock in the majority of cardiac tertiary centres. Affected are 2% of 40 000 cardiac surgical patients who fail to separate from cardiopulmonary bypass and around 5% of 25 000 myocardial infarction patients who progress to cardiogenic shock.1 ,2 These disparate groups suffer ischaemia followed by reperfusion injury, then lethal but potentially recoverable myocardial stunning.3 Young patients with myocarditis or postpartum cardiomyopathy may experience a similar fate through an inflammatory process. Chronic heart failure patients suffer bouts of decompensation from which they can be rescued. At a conservative estimate these categories account for between 2000 and 3000 patients per annum in the UK.
Whereas myocardial stunning and most episodes of myocarditis will resolve over days or weeks, the immediate vicious cycle of cardiogenic shock rapidly causes metabolic derangement and death.4 Adrenergic inotropes may temporarily increase blood pressure but at the expense of tachycardia, elevated oxygen consumption and endocardial necrosis. Though widely available and supported by AHA/ACC and ESC guidelines, the intra-aortic balloon pump does not significantly increase cardiac output (<500 ml/min). Numerous clinical trials have failed to demonstrate either reduction in infarct size or survival benefit in established cardiogenic shock.5–7 Mechanical blood pumps were developed in the 1970s, initially to support patients who could not be weaned from cardiopulmonary bypass during cardiac surgery. Early designs sought to replicate native heart function by providing stroke volume, pulse pressure and flow up to supra-physiological …