B52-32 Beyond the Sts Score: Prophylactic Impella Support Enables Successful Cabg in a High-risk Esrd Patient With Severe Cardiomyopathy

Abstract Rationale Patients with end-stage renal disease (ESRD), diabetes mellitus, and heart failure with reduced ejection fraction (HFrEF) undergoing coronary artery bypass grafting (CABG) constitute one of the highest-risk surgical populations. In fact, traditional risk models, such as the Society of Thoracic Surgeons (STS) score, have been clearly shown to underestimate in-hospital surgical mortality within this particular group of patients with coexisting severe multiorgan dysfunction. This “risk mismatch” poses a substantial challenge to clinicians, as a “high-risk” (for instance, 8%) but “non-prohibitive-risk” score may not accurately reflect a patient’s actual physiological risk. We present a case where multidisciplinary clinical acumen, defying statistical probability, led to a successful application of prophylactic mechanical circulatory support (MLS). Case A 68-year-old male with a history of ESRD on hemodialysis, diabetes mellitus, anemia, and severe ischemic cardiomyopathy (HFrEF 25%) with prior percutaneous intervention, presented with altered mental status, syncope, and labwork showed elevated troponins. His coronary angiography showed multivessel disease. His preoperative STS-risk-adjusted predicted mortality was calculated at 24.2%. Despite his “high-risk” but not “prohibitive” score, his “true” physiologic risk was substantially underestimated by virtue of his coexisting severe HFrEF and ESRD. Therefore, a strategy of CABG with prophylactic MCS was decided upon. An Impella 5.5 was inserted intra-operatively. His post-operative course was complex, with multiple days of vasopressors and continuous venovenous hemodialysis (CVVHD). His initial postoperative Sequential Organ Failure Assessment (SOFA) score was approximately 13, confirming a high-risk assessment. Hemodynamics were stabilized with vasopressors and Impella-induced ventricular offloading, which was successfully weaned and removed on post-operative day 7. Subsequently, the patient was extubated and weaned off of oxygen and vasopressors with an uneventful transition to the medicine floor. Discussion This case highlights a significant limitation of statistical risk models in patients with complex, multi-system organ failures. The 24.2% STS score, compared to a high SOFA score, seriously underestimated the patient’s mortality risk, necessitating prolonged use of MCS support. “Critical thinking” of the multidisciplinary team was proactive implantation of an Impella as an “enabling” strategy, versus “rescue” therapy, which allowed for crucial hemodynamic support and ventricular unloading, prevented irreversible cardiogenic shock, in a patient with no physiologic reserve. This particular case highlights that in a high-risk population like ESRD patients with severe HFREF, clinician judgment takes precedence over statistical probabilities. An “aggressive and strategic” MCS plan may be warranted even in the absence of a “prohibitive” STS score to achieve survival in these “functionally prohibitive” patients. This abstract is funded by: None