Monitoring a Mystery: The Unknown Right Ventricle during Left Ventricular Unloading with Impella in Patients with Cardiogenic Shock.

Background: Right ventricular (RV) dysfunction or failure occurs in more than 30% of patients in cardiogenic shock (CS). However, the importance of timely diagnosis of prognostically relevant impairment of RV function is often underestimated. Moreover, data regarding the impact of mechanical circulatory support like the Impella on RV function are rare. Here, we investigated the effects of the left ventricular (LV) Impella on RV function. Moreover, we aimed to identify the most optimal and the earliest applicable parameter for bedside monitoring of RV function by comparing the predictive abilities of three common RV function parameters: the pulmonary artery pulsatility index (PAPi), the ratio of right atrial pressure to pulmonary capillary wedge pressure (RA/PCWP), and the right ventricular stroke work index (RVSWI). Methods: The data of 50 patients with CS complicating myocardial infarction, supported with different flow levels of LV Impella, were retrospectively analyzed. Results: Enhancing Impella flow (1.5 to 2.5 L/min ± 0.4 L/min) did not lead to a significant variation in PAPi (p = 0.717), RA/PCWP (p = 0.601), or RVSWI (p = 0.608), indicating no additional burden for the RV. PAPi revealed the best ability to connect RV function with global hemodynamic parameters, i.e., cardiac index (CI; p < 0.001, 95% CI: 0.181-0.663), pulmonary capillary wedge pressure (PCWP; p = 0.005, 95% CI: -6.721--1.26), central venous pressure (CVP; p < 0.001, 95% CI: -7.89-5.575), and indicators of tissue perfusion (central venous oxygen saturation (SvO2); p = 0.008, 95% CI: 1.096-7.196). Conclusions: LV Impella does not impair RV function. Moreover, PAPi seems to be to the most effective and valid predictor for early bedside monitoring of RV function.

Discussion of hemodynamic optimization strategies and the canonical understanding of hemodynamics during biventricular mechanical support in cardiogenic shock: does the flow balance make the difference?

BACKGROUND: Mechanical circulatory support (MCS) devices may stabilize patients with severe cardiogenic shock (CS) following myocardial infarction (MI). However, the canonical understanding of hemodynamics related to the determination of the native cardiac output (CO) does not explain or support the understanding of combined left and right MCS. To ensure the most optimal therapy control, the current principles of hemodynamic measurements during biventricular support should be re-evaluated. METHODS: Here we report a protocol of hemodynamic optimization strategy during biventricular MCS (VA-ECMO and left ventricular Impella) in a case series of 10 consecutive patients with severe cardiogenic shock complicating myocardial infarction. During the protocol, the flow rates of both devices were switched in opposing directions (+ / - 0.7 l/min) for specified times. To address the limitations of existing hemodynamic measurement strategies during biventricular support, different measurement techniques (thermodilution, Fick principle, mixed venous oxygen saturation) were performed by pulmonary artery catheterization. Additionally, Doppler ultrasound was performed to determine the renal resistive index (RRI) as an indicator of renal perfusion. RESULTS: The comparison between condition 1 (ECMO flow > Impella flow) and condition 2 (Impella flow > VA-ECMO flow) revealed significant changes in hemodynamics. In detail, compared to condition 1, condition 2 results in a significant increase in cardiac output (3.86 ± 1.11 vs. 5.44 ± 1.13 l/min, p = 0.005) and cardiac index (2.04 ± 0.64 vs. 2.85 ± 0.69, p = 0.013), and mixed venous oxygen saturation (56.44 ± 6.97% vs. 62.02 ± 5.64% p = 0.049), whereas systemic vascular resistance decreased from 1618 ± 337 to 1086 ± 306 s*cm-5 (p = 0.002). Similarly, RRI decreased in condition 2 (0.662 ± 0.05 vs. 0.578 ± 0.06, p = 0.003). CONCLUSIONS: To monitor and optimize MCS in CS, PA catheterization for hemodynamic measurement is applicable. Higher Impella flow is superior to higher VA-ECMO flow resulting in a more profound increase in CO with subsequent improvement of organ perfusion.

Renal Protection and Hemodynamic Improvement by Impella® Microaxial Pump in Patients with Cardiogenic Shock.

Acute kidney injury is one of the most frequent and prognostically relevant complications in cardiogenic shock. The purpose of this study was to evaluate the potential effect of the Impella® pump on hemodynamics and renal organ perfusion in patients with myocardial infarction complicating cardiogenic shock. Between January 2020 and February 2022 patients with infarct-related cardiogenic shock supported with the Impella® pump were included in this single-center prospective short-term study. Changes in hemodynamics on different levels of Impella® support were documented with invasive pulmonal arterial catheter. As far as renal function is concerned, renal perfusion was assessed by determining the renal resistive index (RRI) using Doppler sonography. A total of 50 patients were included in the analysis. The increase in the Impella® output by a mean of 1.0 L/min improved the cardiac index (2.7 ± 0.86 to 3.3 ± 1.1 p < 0.001) and increased central venous oxygen saturation (62.6 ± 11.8% to 67.4 ± 10.5% p < 0.001). On the other side, the systemic vascular resistance (1035 ± 514 N·s/m5 to 902 ± 371 N·s/m5p = 0.012) and the RRI were significantly reduced (0.736 ± 0.07 to 0.62 ± 0.07 p < 0.001). Furthermore, in the overall cohort, a baseline RRI ≥ 0.8 was associated with a higher frequency of renal replacement therapy (71% vs. 39% p = 0.04), whereas the consequent reduction of the RRI below 0.7 during Impella® support improved the glomerular filtration rate (GFR) during hospital stay (15 ± 3 days; 53 ± 16 mL/min to 83 ± 16 mL/min p = 0.04). Impella® support in patients with cardiogenic shock seems to improve hemodynamics and renal organ perfusion. The RRI, a well-known parameter for the early detection of acute kidney injury, can be directly influenced by the Impella® flow rate. Thus, a targeted control of the RRI by the Impella® pump could mediate renal organ protection.

Comparison of Mechanical Support with Impella or Extracorporeal Life Support in Post-Cardiac Arrest Cardiogenic Shock: A Propensity Scoring Matching Analysis.

Our aim was to compare the outcomes of Impella with extracorporeal life support (ECLS) in patients with post-cardiac arrest cardiogenic shock (CS) complicating acute myocardial infarction (AMI). This was a retrospective study of patients resuscitated from out of hospital cardiac arrest (OHCA) with post-cardiac arrest CS following AMI (May 2015 to May 2020). Patients were supported either with Impella 2.5/CP or ECLS. Outcomes were compared using propensity score-matched analysis to account for differences in baseline characteristics between groups. 159 patients were included (Impella, n = 105; ECLS, n = 54). Hospital and 12-month survival rates were comparable in the Impella and the ECLS groups (p = 0.16 and p = 0.3, respectively). After adjustment for baseline differences, both groups demonstrated comparable hospital and 12-month survival (p = 0.36 and p = 0.64, respectively). Impella patients had a significantly greater left ventricle ejection-fraction (LVEF) improvement at 96 h (p < 0.01 vs. p = 0.44 in ECLS) and significantly fewer device-associated complications than ECLS patients (15.2% versus 35.2%, p < 0.01 for relevant access site bleeding, 7.6% versus 20.4%, p = 0.04 for limb ischemia needing intervention). In subgroup analyses, Impella was associated with better survival in patients with lower-risk features (lactate < 8.6 mmol/L, time from collapse to return of spontaneous circulation < 28 min, vasoactive score < 46 and Horowitz index > 182). In conclusion, the use of Impella 2.5/CP or ECLS in post-cardiac arrest CS after AMI was associated with comparable adjusted hospital and 12-month survival. Impella patients had a greater LVEF improvement than ECLS patients. Device-related access-site complications occurred more frequently in patients with ECLS than Impella support.

Left Ventricle Architecture and Valvular Integrity Following Microaxial Mechanical Support: A Two-Year Follow-Up Study.

Although the use of microaxilar mechanical circulatory support systems may improve the outcome of patients with cardiogenic shock (CS), little is known about its effect on the long-term structural integrity of left ventricular (LV) valves as well as on the development of LV-architecture. Therefore, we aimed to study the integrity of the LV valves and architecture and function after Impella support. Thus, 84 consecutive patients were monitored over two years having received ImpellaTM CP (n = 24) or 2.5 (n = 60) for refractory CS (n = 62) or for high-risk percutaneous coronary interventions (n = 22) followed by optimal medical treatment. Beside a significant increase in LV ejection fraction after two years (p ≤ 0.03 vs. pre-implantation), we observed a statistically significant decrease in LV dilation (p < 0.001) and severity of mitral valve regurgitation (p = 0.007) in the two-year follow-up period, suggesting an improved LV architecture. Neither the duration of support, nor the size of the Impella device or the indication for its use revealed any devastating impact on aortic or mitral valve integrity. These findings indicate that Impella device is a safe means of support of LV-function without detrimental long-term effects on the structural integrity of LV valves regardless of the size of the device or the indication of support.

Biventricular Unloading with Impella and Venoarterial Extracorporeal Membrane Oxygenation in Severe Refractory Cardiogenic Shock: Implications from the Combined Use of the Devices and Prognostic Risk Factors of Survival.

Since mechanical circulatory support (MCS) devices have become integral component in the therapy of refractory cardiogenic shock (RCS), we identified 67 patients in biventricular support with Impella and venoarterial Extracorporeal Membrane Oxygenation (VA-ECMO) for RCS between February 2013 and December 2019 and evaluated the risk factors of mortality in this setting. Mean age was 61.07 ± 10.7 and 54 (80.6%) patients were male. Main cause of RCS was acute myocardial infarction (AMI) (74.6%), while 44 (65.7%) were resuscitated prior to admission. The mean Simplified Acute Physiology Score II (SAPS II) and Sequential Organ Failure Assessment Score (SOFA) score on admission was 73.54 ± 16.03 and 12.25 ± 2.71, respectively, corresponding to an expected mortality of higher than 80%. Vasopressor doses and lactate levels were significantly decreased within 72 h on biventricular support (p < 0.05 for both). Overall, 17 (25.4%) patients were discharged to cardiac rehabilitation and 5 patients (7.5%) were bridged successfully to ventricular assist device implantation, leading to a total of 32.8% survival on hospital discharge. The 6-month survival was 31.3%. Lactate > 6 mmol/L, vasoactive score > 100 and pH < 7.26 on initiation of biventricular support, as well as Charlson comorbity index > 3 and prior resuscitation were independent predictors of survival. In conclusion, biventricular support with Impella and VA-ECMO in patients with RCS is feasible and efficient leading to a better survival than predicted through traditional risk scores, mainly via significant hemodynamic improvement and reduction in lactate levels.

Early Impella Support in Postcardiac Arrest Cardiogenic Shock Complicating Acute Myocardial Infarction Improves Short- and Long-Term Survival.

OBJECTIVES: Early mechanical circulatory support with Impella may improve survival outcomes in the setting of postcardiac arrest cardiogenic shock after out-of-hospital cardiac arrest complicating acute myocardial infarction. However, the optimal timing to initiate mechanical circulatory support in this particular setting remains unclear. Therefore, we aimed to compare survival outcomes of patients supported with Impella 2.5 before percutaneous coronary intervention (pre-PCI) with those supported after percutaneous coronary intervention (post-PCI). DESIGN: Retrospective single-center study between September 2014 and December 2019 admitted to the Cardiac Arrest Center in Marburg, Germany. PATIENTS: Out of 2,105 patients resuscitated from out-of-hospital cardiac arrest due to acute myocardial infarction with postcardiac arrest cardiogenic shock between September 2014 and December 2019 and admitted to our regional cardiac arrest center, 81 consecutive patients receiving Impella 2.5 during admission coronary angiogram were identified. OUTCOMES/MEASUREMENTS: Survival outcomes were compared between those with Impella support pre-PCI to those with support post-PCI. MAIN RESULTS: A total of 81 consecutive patients with infarct-related postcardiac arrest shock supported with Impella 2.5 during admission coronary angiogram were included. All patients were in profound cardiogenic shock requiring catecholamines at admission. Overall survival to discharge and at 6 months was 40.7% and 38.3%, respectively. Patients in the pre-PCI group had a higher survival to discharge and at 6 months as compared to patients of the post-PCI group (54.3% vs 30.4%; p = 0.04 and 51.4% vs 28.2%; p = 0.04, respectively). Furthermore, the patients in the early support group demonstrated a greater functional recovery of the left ventricle and a better restoration of the end-organ function when Impella support was initiated prior to percutaneous coronary intervention. CONCLUSIONS: Our results suggest that the early initiation of mechanical circulatory support with Impella 2.5 prior to percutaneous coronary intervention is associated with improved hospital and 6-month survival in patients with postcardiac arrest cardiogenic shock complicating acute myocardial infarction.

Comparison of Mortality Risk Models in Patients with Postcardiac Arrest Cardiogenic Shock and Percutaneous Mechanical Circulatory Support.

BACKGROUND: Although scoring systems are widely used to predict outcomes in postcardiac arrest cardiogenic shock (CS) after out-of-hospital cardiac arrest (OHCA) complicating acute myocardial infarction (AMI), data concerning the accuracy of these scores to predict mortality of patients treated with Impella in this setting are lacking. Thus, we aimed to evaluate as well as to compare the prognostic accuracy of acute physiology and chronic health II (APACHE II), simplified acute physiology score II (SAPS II), sepsis-related organ failure assessment (SOFA), the intra-aortic balloon pump (IABP), CardShock, the prediction of cardiogenic shock outcome for AMI patients salvaged by VA-ECMO (ENCOURAGE), and the survival after venoarterial extracorporeal membrane oxygenation (SAVE) score in patients with OHCA refractory CS due to an AMI treated with Impella 2.5 or CP. METHODS: Retrospective study of 65 consecutive Impella 2.5 and 32 CP patients treated in our cardiac arrest center from September 2015 until June 2020. RESULTS: Overall survival to discharge was 44.3%. The expected mortality according to scores was SOFA 70%, SAPS II 90%, IABP shock 55%, CardShock 80%, APACHE II 85%, ENCOURAGE 50%, and SAVE score 70% in the 2.5 group; SOFA 70%, SAPS II 85%, IABP shock 55%, CardShock 80%, APACHE II 85%, ENCOURAGE 75%, and SAVE score 70% in the CP group. The ENCOURAGE score was the most effective predictive model of mortality outcome presenting a moderate area under the curve (AUC) of 0.79, followed by the CardShock, APACHE II, IABP, and SAPS score. These derived an AUC between 0.71 and 0.78. The SOFA and the SAVE scores failed to predict the outcome in this particular setting of refractory CS after OHCA due to an AMI. CONCLUSION: The available intensive care and newly developed CS scores offered only a moderate prognostic accuracy for outcomes in OHCA patients with refractory CS due to an AMI treated with Impella. A new score is needed in order to guide the therapy in these patients.

Comparison of mechanical circulatory support with venoarterial extracorporeal membrane oxygenation or Impella for patients with cardiogenic shock: a propensity-matched analysis.

BACKGROUND: Percutaneous mechanical circulatory devices are increasingly used in patients with cardiogenic shock (CS). As evidence from randomized studies comparing these devices are lacking, optimal choice of the device type is unclear. Here we aim to compare outcomes of patients with CS supported with either Impella or vaECMO. METHODS: Retrospective single-center analysis of patients with CS, from September 2014 to September 2019. Patients were assisted with either Impella 2.5/CP or vaECMO. Patients supported ultimately with both devices were analyzed according to the first device implanted. Primary outcomes were hospital and 6-month survival. Secondary endpoints were complications. Survival outcomes were compared using propensity-matched analysis to account for differences in baseline characteristics between both groups. RESULTS: A total of 423 patients were included (Impella, n = 300 and vaECMO, n = 123). Survival rates were similar in both groups (hospital survival: Impella 47.7% and vaECMO 37.3%, p = 0.07; 6-month survival Impella 45.7% and vaECMO 35.8%, p = 0.07). There was no significant difference in survival rates, even after adjustment for baseline differences (hospital survival: Impella 50.6% and vaECMO 38.6%, p = 0.16; 6-month survival Impella 45.8% and vaECMO 38.6%, p = 0.43). Access-site bleeding and leg ischemia occurred more frequently in patients with vaECMO (17% versus 7.3%, p = 0.004; 17% versus 7.7%, p = 0.008). CONCLUSIONS: In this retrospective analysis of patients with CS, treatment with Impella 2.5/CP or vaECMO was associated with similar hospital and 6-month survival rates. Device-related access-site vascular complications occurred more frequently in the vaECMO group. A randomized trial is warranted to examine the effects of these devices on outcomes and to determine the optimal device choice in patients with CS.

Corticosteroids in neurological disorders: The dark side.

Corticosteroids are among the most commonly prescribed drugs by physicians of nearly all medical specialties. Their widespread use in clinical neurology is based either on randomized studies or, most often, on clinical experience and experts' opinion. Besides the well-known adverse effects of corticosteroids, they may also induce or worsen certain neurological disorders. The purpose of this review is to highlight the negative impact of these drugs on these disorders with emphasis on putative pathophysiological mechanisms of this association.