Factors associated with Acute Limb Ischemia in Cardiogenic Shock and downstream Clinical Outcomes: Insights from the Cardiogenic Shock Working Group.

BACKGROUND: There are limited data depicting the prevalence and ramifications of acute limb ischemia (ALI) among cardiogenic shock (CS) patients. METHODS: We employed data from the Cardiogenic Shock Working Group (CSWG), a consortium including 33 sites. We constructed a multi-variable logistic regression to examine the association between clinical factors and ALI, we generated another logistic regression model to ascertain the association of ALI with mortality. RESULTS: There were 7,070 patients with CS and 399 (5.6%) developed ALI. Patients with ALI were more likely to be female (40.4% versus 29.4%) and have peripheral arterial disease (13.8% versus 8.3%). Stratified by maximum SCAI shock stage, the rates of ALI were stage B 0.0%, stage C 1.8%, stage D 4.1%, and stage E 10.3%. Factors associated with higher risk for ALI included: peripheral vascular disease OR 2.24 (95% CI: 1.53 - 3.23; p < 0.01) and ≥ 2 mechanical circulatory support (MCS) devices OR 1.66 (95% CI: 1.24 - 2.21, p < 0.01). ALI was highest for VA-ECMO patients (11.6%) or VA-ECMO + IABP/Impella CP (16.6%) yet use of distal perfusion catheters was less than 50%. Mortality was 38.0% for CS patients without ALI but 57.4% for CS patients with ALI. ALI was significantly associated with mortality, adjusted OR 1.40 (95% CI 1.01 - 1.95, p < 0.01). CONCLUSIONS: The rate of ALI was 6% among CS patients. Factors most associated with ALI include peripheral vascular disease and multiple MCS devices. The downstream ramifications of ALI were dire with a considerably higher risk of mortality.

Contemporary outcome of unplanned right ventricular assist device for severe right heart failure after continuous-flow left ventricular assist device insertion.

OBJECTIVES: The timely use of a right ventricular assist device (RVAD) becomes necessary for severe right heart failure (RHF) after left ventricular assist device (LVAD) insertion. This study evaluates outcomes in patients who required unplanned RVAD support early after continuous-flow (CF) LVAD insertion. METHODS: We retrospectively reviewed 305 patients who underwent HeartMate II/HeartWare CF-LVAD insertion between 2009 and 2014. Twenty-seven (9%) patients required unplanned RVAD for severe RHF early after LVAD insertion. We compared early and late outcomes in patients with and without RVAD. RESULTS: The median time to RVAD implantation after primary CF-LVAD implantation was 1.0 (0-3) day. Seventeen (63%) patients could be weaned from RVAD after median of 14 (10-18) days. In 278 patients in the isolated LVAD group, overall survival at 3 and 12 months was 95% and 86%, whereas 59% and 54% in the unplanned RVAD group, respectively ( P < 0.001). The 12-month overall survival rate in patients who were weaned from RVAD was 75% ( P = 0.189 vs isolated LVAD group), whereas in patients who could not be weaned from RVAD, the overall survival was 20% ( P < 0.001 vs RVAD weaning group and isolated LVAD group). Readmission free rate for RHF at 1 year was 53% in the unplanned RVAD group and 90% in the isolated LVAD group ( P = 0.002). CONCLUSIONS: Among patients who required unplanned RVAD after CF-LVAD implantation, above 60% of the patients could be weaned from RVAD. However, careful attention should be paid to the recurrent or sustained RHF.

Importance of stratifying acute kidney injury in cardiogenic shock resuscitated with mechanical circulatory support therapy.

OBJECTIVE: Although the outcomes of patients with cardiogenic shock remain poor, short-term mechanical circulatory support has become an increasingly popular modality for hemodynamic assistance and organ preservation. Because the kidney is exquisitely sensitive to poor perfusion, acute kidney injury is a common sequela of cardiogenic shock. This study examines the incidence and clinical impact of acute kidney injury in patients with short-term mechanical circulatory support for cardiogenic shock. METHODS: Retrospective review was performed of 293 consecutive patients with cardiogenic shock who were treated with short-term mechanical circulatory support. The well-validated 2014 Kidney Disease Improving Global Outcomes criteria were used to stage acute kidney injury. Outcomes of interest were long-term mortality and renal recovery. RESULTS: Acute kidney injury developed in 177 of 293 patients (60.4%), of whom 113 (38.6%) were classified with stage 3 (severe). Kaplan-Meier survival estimates indicated a 1-year survival of 49.2% in the nonsevere (stages 0-2) acute kidney injury cohort versus 27.3% in the severe acute kidney injury cohort (P < .001). Multivariable Cox regression demonstrated that severe acute kidney injury was a predictor of long-term mortality (hazard ratio, 1.54; confidence interval, 1.10-2.14; P = .011). Among hospital survivors, renal recovery occurred more frequently (82.4% vs 63.2%, P = .069) and more quickly (5.6 vs 24.5 days, P < .0001) in the nonsevere than in the severe acute kidney injury group. CONCLUSIONS: Acute kidney injury is common and frequently severe in patients in cardiogenic shock treated with short-term mechanical circulatory support. Milder acute kidney injury resolves with survival comparable to patients without acute kidney injury. Severe acute kidney injury is an independent predictor of long-term mortality. Nonetheless, many surviving patients with acute kidney injury do experience gradual renal recovery.

Outcome of heart transplantation after bridge-to-transplant strategy using various mechanical circulatory support devices.

OBJECTIVES: Orthotopic heart transplantation (OHT) is limited by a chronic shortage of donors. With the evolution of technology, more patients have been bridged to transplant (BTT) through various pathways using various types of mechanical circulatory support. We compared short- and long-term outcomes among these various strategies of BTT. METHODS: We retrospectively reviewed 410 patients who had OHT between January 2009 and April 2015. Patients were divided into 4 groups according to BTT status: primary OHT without bridging (Group A, n = 246); bridge with implantable continuous-flow left ventricular assist device (CF-LVAD) (Group B, n = 130); bridge with short-term mechanical circulatory support (Group C, n = 16) and bridge with multiple mechanical circulatory supports, including short-term mechanical circulatory support and CF-LVAD (Group D, n = 18). Early and late outcomes after OHT were compared among the groups. RESULTS: The total duration of device support was 110.4 patient-years, 1.8 patient-years and 21.0 patient-years in Groups B, C and D, respectively. Patients who were bridged with CF-LVAD (Groups B and D) were more likely to have larger body size, blood type O, idiopathic dilated cardiomyopathy and ischaemic cardiomyopathy as an aetiology, lower total bilirubin level and longer waiting time on the United Network for Organ Sharing Status 1A. There was no statistical difference between the 4 groups in serum panel reactive antigen levels before OHT. Hospital mortality was 4% in Group A, 8% in Group B, 13% in Group C and 6% in Group D (P = 0.307). Post-transplant survival at 3 years was 80% in Group A, 82% in Group B, 75% in Group C and 88% in Group D (P = 0.752). CONCLUSIONS: BTT strategies using various mechanical circulatory support devices can provide comparable clinical outcomes to primary OHT. Flexibility in the use of both short-term mechanical circulatory support and CF-LVAD is necessary depending on the patient's background.