Occurrence, predictors, and management of late vascular complications following extracorporeal membrane oxygenation.

OBJECTIVE: Vascular complications (VCs) associated with extracorporeal membrane oxygenation (ECMO) during index hospitalization are prevalent and associated with increased mortality. Few studies have evaluated late VCs following ECMO; this study aims to assess occurrence and management practices of late VCs following discharge. METHODS: A retrospective single-institution review was performed of all patients surviving initial hospitalization after being cannulated for central or peripheral veno-venous (VV) or veno-arterial (VA) ECMO between January 1, 2019, and December 31, 2020. Primary outcomes were to categorize and determine the rate of late VCs. Late VCs were defined as any cannulated vessel injury resulting from ECMO cannulation presenting after discharge from index hospitalization. Analysis was conducted by cannulated vessel and stratified by VV or VA ECMO configurations. RESULTS: A total of 229 patients were identified, of which 50.6% (n = 116) survived until discharge. Late VCs occurred in 7.8% of the surviving cohort (n = 9/116); with a median time until presentation of 150 days (interquartile range, 83-251 days). The most common late VC was infection (n = 5; 55.6%) followed by progression to limb-threatening ischemia (n = 4; 44.4%). Urgent procedures were required in 55.6% of patients (n = 5), whereas 44.4% (n = 4) were elective interventions. Interventions performed for management of late VCs included lower extremity arterial revascularization (n = 6; 66.7%), major (n = 1; 11.1%) or minor amputation (n = 1; 11.1%), and wound debridement (n = 1; 11.1%). The majority of patients presenting with late VCs had initially been cannulated for peripheral VA ECMO (n = 8; 88.9%), and one patient (11.1%) was cannulated for peripheral VV ECMO. VCs during index hospitalization were seen in 77.8% of patients (n = 7) returning with late VCs. Odds for late VCs were significantly increased in patients that had been cannulated for ECMO as part of extracorporeal cardiopulmonary resuscitation (odds ratio, 8.4; P = .016) and in cases where patients had experienced an index VC during index hospitalization (odds ratio, 19.3; P = .001). CONCLUSIONS: Late vascular complications after peripheral ECMO cannulation are not rare, particularly after arterial cannulation. Patients should be followed closely early after surviving ECMO with wound evaluation and formal assessment of perfusion with ankle-branchial indices in the cannulated limb.

Improvement in 2-year survival for ventricular assist device patients after implementation of an intensive surveillance protocol.

BACKGROUND: This study was conducted to determine the effect of a disease-management model termed an "intensive surveillance protocol" (ISP) on survival in ventricular assist device (VAD) patients. This intervention consisted of a formalized, protocol-driven, multi-disciplinary team approach to VAD patient follow-up initiated August 1, 2006. The goal was to attain an internal program benchmark of 70% survival at 2 years. Historically, 2-year survival after VAD implant has been sub-optimal, and no patient management algorithms have been formally tested to determine their effect on 2-year survival. METHODS: The study comprised 76 patients, of whom 26 had a VAD as destination therapy (DT) and 50 as a bridge to transplant (BTT), from July 1, 2003, to June 30, 2008. Survival before and after initiation of ISP was compared. A parametric hazard multivariable analysis, with a time-varying covariable for implementation of ISP, was used to evaluate of other factors affecting survival. RESULTS: Survival at 16 months was 100% for DT patients who received a VAD after August 1, 2006 vs 64% for the earlier era (p = 0.06). For BTT, 16- month survival was 71% vs 43% (p = 0.03). Predicted 2-year survival before and after implementation of the ISP improved from 30% to 87% for DT (p = 0.02) and from 20% to 61% for BTT patients (p = 0.01). Predictors of midterm survival by multivariable analysis included ISP (p = 0.004), younger age (p = 0.03), non-emergent implant (p < 0.0001), and isolated left ventricular VAD (p < 0.0001). After adjustment for covariables, the ISP was associated with a 70% reduction in the hazard for death for the entire cohort (p = 0.004). The effect of ISP was also significant in the patients who received the HeartMate XVE (Thoratec, Pleasanton, CA), which spanned both eras of the study. CONCLUSIONS: Survival improved for DT and BTT VAD patients after implementation of the ISP, with a dramatic decrease in hazard for death. Although the transition from pulsatile to axial flow technology occurred during the study period and likely contributed to improved outcomes, the institution of the ISP provided an important and significant contribution to improved survival through a proactive approach to patient management, allowing earlier identification of potential adverse events. For optimal outcomes, VAD patients require intensive follow-up surveillance protocols that have previously become standard in the care of heart transplant patients.

Clinical management of continuous-flow left ventricular assist devices in advanced heart failure.

Continuous-flow left ventricular assist devices (LVAD) have emerged as the standard of care for advanced heart failure patients requiring long-term mechanical circulatory support. Evidence-based clinical management of LVAD-supported patients is becoming increasingly important for optimizing outcomes. In this state-of-art review, we propose key elements in managing patients supported with the new continuous-flow LVADs. Although most of the presented information is largely based on investigator experience during the 1,300-patient HeartMate II clinical trial, many of the discussed principles can be applied to other emerging devices as well. Patient selection, pre-operative preparation, and the timing of LVAD implant are some of the most important elements critical to successful circulatory support and are principles universal to all devices. In addition, proper nutrition management and avoidance of infectious complications can significantly affect morbidity and mortality during LVAD support. Optimizing intraoperative and peri-operative care, and the monitoring and treatment of other organ system dysfunction as it relates to LVAD support, are discussed. A multidisciplinary heart failure team must be organized and charged with providing comprehensive care from initial referral until support is terminated. Preparing for hospital discharge requires detailed education for the patient and family or friends, with provisions for emergencies and routine care. Implantation techniques, troubleshooting device problems, and algorithms for outpatient management, including the diagnosis and treatment of related problems associated with the HeartMate II, are discussed as an example of a specific continuous-flow LVAD. Ongoing trials with other continuous-flow devices may produce additional information in the future for improving clinical management of patients with these devices.

Native aortic valve insufficiency in patients with left ventricular assist devices.

Management of mild to moderate aortic insufficiency in patients with a left ventricular assist device remains controversial. We report 3 patients with aortic insufficiency and pulsatile left ventricular assist devices treated with a central aortic valve coapting suture. Two of the repairs have been durable for more than 1 year and aspirin appears to be sufficient anticoagulation.

Managing device infections: are we progressing or is infection an insurmountable obstacle?

This article reviews infections that occur in patients with implanted mechanical circulatory support devices and presents recent data for signs of progress in controlling the incidence and impact of these infections. Two types of comparisons are used to examine this question. First, the outcomes of patients with HeartMate vented electric left ventricular assist devices (VADs) (Thoratec Corp, Pleasanton, CA) implanted during the REMATCH Trial are compared with the outcome of more recent patients who received this pump as destination therapy. Second, the outcome of patients who received a smaller left VAD (e.g., an axial flow VAD) or a fully implanted left VAD are reported and contrasted with results from the REMATCH era. Data are presented to support the hypothesis that improvements in patient selection, patient management, device durability, and device design have resulted in lower rates of infection and infection-related death for patients who require mechanical circulatory support.