Peripheral artery disease and extracorporeal membrane oxygenation: Examining a high-risk cohort over time.

OBJECTIVE: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a resource-intensive approach for the management of refractory cardiogenic shock. Within this population exists a substantial cohort of patients with peripheral artery disease (PAD), which independently increases the risk of complications and all-cause mortality. We studied 10-year national trends of the impact of PAD among VA-ECMO recipients to better understand the prevalence of PAD and implications on outcomes in this vulnerable population.

METHODS: This 10-year retrospective, propensity score-matched study identified all adult patients (≥18) who underwent VA-ECMO between 2009 and 2018, from a large US database (National Inpatient Sample). Patients with an ICD diagnosis of PAD were identified. The primary endpoints of in-hospital mortality, bleeding complications and major limb loss (above- or below-knee amputation) were compared between patients with PAD to those without.

RESULTS: A total of 6768 patients were identified, of which 342 (5.3%) had PAD. The median age at admission was significantly higher in PAD patients [64 years vs. 55 years; p < .01], as was male gender [71% vs. 64%; p < .01]. Patients with PAD had higher rates of smoking (38.9% vs. 23.3%), hypertension (71.1% vs. 50%), diabetes (37.4% vs. 27.0%), chronic kidney disease (30.1% vs. 18.0%), coronary artery disease (76.0% vs. 35.0%) and dyslipidemia (76.0% vs. 35.0); all p < .01. After propensity-matching 2:1 for comorbidities, PAD patients were found to have significantly greater overall complications, including in-hospital mortality, bleeding, surgical wound infections, pseudoaneurysms, and major adverse limb events [71.9% vs. 63.9%; p < .01]. Subgroup analysis revealed greater in-hospital mortality [62.2% vs. 55.3%; p < .05], major amputations [4.1% vs. 0.3%; p < .01] and blood transfusions [32.2% vs. 26.2%; p < .05] in PAD patients. Over 2014-2018, the non-PAD group demonstrated statistically discernable trends in a 51.1% decrease in overall complications and a 28.1% increase in survival to discharge (all p < .01). Over the same time period the PAD cohort experienced a modest, nonsignificant, decrease in complications [7.0%, p = .40] and a decrease in those surviving to discharge [47.1% vs. 40.5%, p = .91].

CONCLUSION: Patients with PAD on VA-ECMO are sicker at baseline and experience significantly greater major amputations and higher in-hospital mortality. They have not benefitted from the considerable decrease in complication rates and increase in survival to discharge over time as compared to their non-PAD counterparts. These findings demonstrate the substantial frailty of the PAD population within an already high-risk cohort, and highlight the need for better procedural approaches and innovative technologies.