Hemodynamic assessment and risk classification for successful weaning of Impella in patients with cardiogenic shock

Abstract

Background Clinical predictors for successful weaning of patients from Impella heart pump have not been clarified. We aimed to elucidate the relationship between pulmonary artery catheter (PAC) parameters at the time of Impella weaning and subsequent outcomes. Methods We enrolled consecutive patients who had received Impella for cardiogenic shock. PAC data were collected immediately before Impella weaning. Patients were classified as non‐survivors if they died or required any mechanical circulatory support reintroduction within 30 days of weaning. Results Of 81 patients enrolled, 61 underwent Impella weaning. Of these, 16 were non‐survivors. Predictive indicators of non‐survival were high pulmonary artery wedge pressure (PAWP; hazard ratio [HR] per 5 mm Hg 1.97, 95% CI 1.35–2.80; p < 0.001), high mean pulmonary artery pressure (MPAP; HR per 5 mm Hg 1.90, 1.38–2.58; p < 0.001), and low cardiac power output (CPO; HR per 0.1 Watts 0.71, 0.52–0.92; p = 0.006). Cutoff values of PAWP 20 mm Hg, MPAP 22 mm Hg, and CPO 0.59 Watts showed strong associations with 30‐day non‐survival risk (low risk 8% in patients with low PAWP and high CPO or 4% in patients with low MPAP and high CPO; high risk 100% in patients with high PAWP and low CPO or 82% in patients with high MPAP and low CPO). Conclusions PAWP or MPAP higher than the cutoff with CPO below the cutoff at Impella weaning were associated with worse outcomes. We proposed a risk classification model for successful Impella weaning using PAC.

JCS/JSCVS/JCC/CVIT 2023 Guideline Focused Update on Indication and Operation of PCPS/ECMO/IMPELLA

“…124, 125 Combining CPO and PAPi in the hemodynamic evaluation facilitates assessment of the risk of withdrawal. 59, 126 The withdrawal method involves gradually lowering the P level by 1-2 increments, confirming hemodynamic stability at P2, and removing the IMPELLA from the left ventricle. The rate of P level decrease varies according to the cause of shock and the degree of LV function.…”

Mechanical circulatory support in cardiogenic shock

“…Although right atrial pressure and PAPi can be used to some extent to assess RV performance for transient changes even under VA-ECMO support, it should be noted that PAPi could be influenced by RV preload. The third step requires meeting the criteria of PAWP < 20 mmHg and CPO ≥ 0.6 watts [ 63 ]; and if met, a final decision is made to wean from Impella.…”

“…If the criteria are not met at any stage, the weaning process should not proceed, and intensification of heart failure therapy or device escalation should be considered. The frequency of concomitant significant mitral regurgitation on echocardiography was reported to be higher in patients with higher PAWP or lower CPO at Impella weaning [ 63 ]. These patients who are at high risk of Impella weaning failure should be evaluated for severity of concomitant mitral regurgitation, and additional interventions such as surgical or edge-to-edge mitral valve repair may be considered prior to decannulation.…”

Clinical outcomes and predictors of success with Impella weaning in cardiogenic shock: a single-center experience

“…The weaning from Impella and its explant, however, are mostly performed in the absence of established algorithms and protocols, mainly based on the experience of the individual centres, and predictors of successful weaning are lacking ( 15 – 18 ).…”