In a recent edition of this Journal, an intriguing study was published which examined the association between (development of) pulmonary congestion (PC) and mortality in patients with post-cardiotomy cardiogenic shock requiring extracorporeal membrane oxygenation (ECMO). [1] Distelmaier and colleagues observed in 266 patients that presence of PC on days 3 and 5 —but not day 0— after ECMO initiation was negatively associated with survival. We were struck by the apparent disparity in impact of PC on mortality between first and subsequent days.