Time course, factors related to, and prognostic impact of venoarterial extracorporeal membrane flow in cardiogenic shock

AIMS

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is currently one of the most used devices in refractory cardiogenic shock. However, there is a lack of evidence on how to set the 'optimal' flow. We aimed to describe the evolution of VA-ECMO flows in a cardiogenic shock population and determine the risk factors of 'high-ECMO flow'.

METHODS AND RESULTS

A 7 year database of patients supported with VA-ECMO was used. Based on the median flow during the first 48 h of the VA-ECMO run, patients were classified as 'high-flow' or 'low-flow', respectively, when median ECMO flow was ≥3.6 or <3.6 L/min. Outcomes included rates of ventilator-associated pneumonia, ECMO-related complications, days on ECMO, days on mechanical ventilation, intensive care unit and hospitalization lengths of stay, and in-hospital and 60 day mortality. Risk factors of high-ECMO flow were assessed using univariate and multivariate cox regression. The study population included 209 patients on VA-ECMO, median age was 51 (40-59) years, and 78% were males. The most frequent aetiology leading to cardiogenic shock was end-stage dilated cardiomyopathy (57%), followed by acute myocardial infarction (23%) and fulminant myocarditis (17%). Among the 209 patients, 105 (50%) were classified as 'high-flow'. This group had a higher rate of ischaemic aetiology (16% vs. 30%, P = 0.023) and was sicker at admission, in terms of worse Simplified Acute Physiology Score II score [40 (26-58) vs. 56 (42-74), P < 0.001], higher lactate [3.6 (2.2-5.8) mmol/L vs. 5.2 (3-9.7) mmol/L, P < 0.001], and higher aspartate aminotransferase [97 (41-375) U/L vs. 309 (85-939) U/L, P < 0.001], among others. The 'low-flow' group had less ventilator-associated pneumonia (40% vs. 59%, P = 0.007) and less days on mechanical ventilation [4 (1.5-7.5) vs. 6 (3-12) days, P = 0.009]. No differences were found in lengths of stay or survival according to the ECMO flow. The multivariate analysis showed that risk factors independently associated with 'high-flow' were mechanical ventilation at cannulation [odds ratio (OR) 3.9, 95% confidence interval (CI) 2.1-7.1] and pre-ECMO lactate (OR 1.1, 95% CI 1.0-1.2).

CONCLUSIONS

In patients with refractory cardiogenic shock supported with VA-ECMO, sicker patients had higher support since early phases, presenting thereafter higher rates of ventilator-associated pneumonia but similar survival compared with patients with lower flows.

Statin Use and In-Hospital Mortality in Patients With Diabetes Mellitus and COVID-19

Background Severe coronavirus disease 2019 (COVID-19) is characterized by a proinflammatory state with high mortality. Statins have anti-inflammatory effects and may attenuate the severity of COVID-19. Methods and Results An observational study of all consecutive adult patients with COVID-19 admitted to a single center located in Bronx, New York, was conducted from March 1, 2020, to May 2, 2020. Patients were grouped as those who did and those who did not receive a statin, and in-hospital mortality was compared by competing events regression. In addition, propensity score matching and inverse probability treatment weighting were used in survival models to examine the association between statin use and death during hospitalization. A total of 4252 patients were admitted with COVID-19. Diabetes mellitus modified the association between statin use and in-hospital mortality. Patients with diabetes mellitus on a statin (n=983) were older (69±11 versus 67±14 years; P<0.01), had lower inflammatory markers (C-reactive protein, 10.2; interquartile range, 4.5-18.4 versus 12.9; interquartile range, 5.9-21.4 mg/dL; P<0.01) and reduced cumulative in-hospital mortality (24% versus 39%; P<0.01) than those not on a statin (n=1283). No difference in hospital mortality was noted in patients without diabetes mellitus on or off statin (20% versus 21%; P=0.82). Propensity score matching (hazard ratio, 0.88; 95% CI, 0.83-0.94; P<0.01) and inverse probability treatment weighting (HR, 0.88; 95% CI, 0.84-0.92; P<0.01) showed a 12% lower risk of death during hospitalization for statin users than for nonusers. Conclusions Statin use was associated with reduced in-hospital mortality from COVID-19 in patients with diabetes mellitus. These findings, if validated, may further reemphasize administration of statins to patients with diabetes mellitus during the COVID-19 era.