Preemptive Impella 5.5 insertion to reduce operative risk in high-risk cardiac surgery: A case report.

INTRODUCTION AND IMPORTANCE: Society of thoracic surgery (STS) risk score has been used as a tool to gauge operative risk of cardiac surgery patients. High-risk patients, with STS risk score > 8 %, are considered as having prohibitive risk and are not offered surgery. There is no established strategy to minimize postoperative hemodynamic instability using mechanical circulatory support (MCS), despite growing interest in utilizing MCS prior to hemodynamic instability. The Impella 5.5 can provide enough perfusion and unload the left ventricle. CASE PRESENTATION: We managed a 75-year-old male with multiple comorbidities and a presumed Society of Thoracic Surgeons (STS) score higher than 9.8 %, who had redo coronary artery bypass grafting and aortic and mitral valve replacement with concomitant implantation of the Impella 5.5. Patient had a good recovery despite developing post-operative atrial fibrillation. DISCUSSION: Impella is used as a mechanical circulatory support device in patients with cardiogenic shock. It provides forward flow and effectively unloads the left ventricle. The concomitant placement of the Impella 5.5 in high-risk cardiac candidates may be associated with reduced operative risk. CONCLUSION: Placement of the device as part of surgical plan can potentially mitigate the perioperative risk by providing adequate endogean perfusion, decrease pressor support, unloading LV.

Cardiac power output ratio: Novel survival predictor after percutaneous ventricular assist device in cardiogenic shock.

AIMS: Currently, there is limited data on prognostic indicators after insertion of percutaneous ventricular assist device (PVAD) in the treatment of cardiogenic shock (CS). This study evaluated the prognostic role of cardiac power output (CPO) ratio, defined as CPO at 24 h divided by early CPO (30 min to 2 h), in CS patients after PVAD. METHODS AND RESULTS: Consecutive CS patients from the QEH-PVAD Registry were followed up for survival at 90 days after PVAD. Among 121 consecutive patients, 98 underwent right heart catheterization after PVAD, with CPO ratio available in 68 patients. The CPO ratio and 24-h CPO, but not the early CPO post PVAD, were significantly associated with 90-day survival, with corresponding area under curve in ROC analysis of 0.816, 0.740, and 0.469, respectively. In multivariate analysis, only the CPO ratio and lactate level at 24 h remained as independent survival predictors. The CPO ratio was not associated with age, sex, and body size. Patients with lower CPO ratio had significantly lower coronary perfusion pressure, worse right heart indices, and higher pulmonary vascular resistance. A lower CPO ratio was also significantly associated with mechanical ventilation and higher creatine kinase levels in myocardial infarction patients. CONCLUSION: In post-PVAD patients, the CPO ratio outperformed the absolute CPO values and other haemodynamic metrics in predicting survival at 90 days. Such a proportional change of CPO over time, likely reflecting native heart function recovery, may help to guide management of CS patients post-PVAD.

High-risk percutaneous coronary intervention with or without mechanical circulatory support: Will Impella show superiority in the PROTECT IV randomized trial?

BACKGROUND: PROTECT IV is a current enrolling randomized controlled trial evaluating high-risk percutaneous coronary intervention (HR-PCI) with prophylactic Impella versus no Impella to reduce the composite primary endpoint of all-cause death, stroke, myocardial infarction (MI), or cardiovascular hospitalization. In a PROTECT IV-like cohort of patients who underwent HR-PCI without Impella, we aimed to report the rate of major adverse events to determine whether the trial is adequately powered. METHODS AND RESULTS: A total of 700 patients meeting similar inclusion/exclusion criteria of PROTECT IV who underwent HR-PCI without Impella at a single tertiary center from 2008 to 2022 were included in the analysis. The composite rates of all-cause death, MI, target lesion revascularization, and target vessel revascularization at 1, 2, and 3 years were estimated using the Kaplan-Meier method, and the results were used to calculate the sample size under the constant hazard ratio assumption and expected number of events to be observed used in planning PROTECT IV. The primary endpoint occurred in 30.8 % of patients at 2 years. PROTECT IV assumes a hazard ratio of 0.75 using a multivariate Cox regression, which, under a 5 % level and 90 % power, yields 516 events. This implies a 2-year primary outcome rate of 50 % for the non-Impella arm. CONCLUSION: Therefore, PROTECT IV estimates that a sample size of 1252 patients is required for Impella to be declared superior to the non-Impella group. Using our observed 2-year outcome of 30.8 %, we estimate that PROTECT IV requires 1966 patients, demonstrating that PROTECT IV is probably underpowered.

Change in left ventricular function and outcomes following high-risk percutaneous coronary intervention with Impella-guided hemodynamic support.

Introduction: High-risk percutaneous coronary interventions (HRPCI) are a potential treatment option for patients with reduced left ventricular ejection fraction (LVEF) and coronary artery disease. The extent to which such intervention is coupled with improvement in LVEF and associated with favorable outcomes is unknown. Methods: We aimed to characterize the incidence and correlates of LVEF improvement after Impella-guided HRPCI, and compare clinical outcomes in patients with versus without LVEF improvement. Data on consecutive patients undergoing Impella-guided HRPCI from a single center registry were analyzed. LVEF-improvement was defined as an absolute increase of LVEF of ≥10% measured at ≥30-days after intervention. The primary outcome was a composite of all-cause death, myocardial infarction or target vessel revascularization within 1-year. Results: Out of 161 consecutive patients undergoing Impella-guided HRPCI from June 2008 to December 2017, 43% (n = 70) demonstrated LVEF-improvement (baseline LVEF of 25.09 ± 6.19 to 33.30 ± 11.98 post intervention). Patients without LVEF-improvement had higher frequency of previous MI (61.5% vs. 37.1%, p = 0.0021), Q-waves on ECG (17.6% vs. 5.7%, p = 0.024) and higher SYNTAX scores (30.8 ± 17.6 vs. 25.2 ± 12.2; p = 0.043). After correction of these confounders by multivariable analysis, no significant differences were found regarding the composite endpoint in patients with versus without LVEF-improvement (34.9% vs. 38.3%; p = 0.48). Discussion: In this single-center retrospective analysis, we report the following findings. First, LVEF improvement of at least 10% was documented in over 40% of patients undergoing Impella supported high-risk PCI. Second, a history of MI, Q-waves on admission ECG, and higher baseline SYNTAX scores were independent correlates of no LVEF improvement. Third, one year rates of adverse CV events were substantial and did not vary by the presence or absence of LVEF improvement Prospective studies with longer follow-up are needed to elucidate the impact of LVEF improvement on clinical outcomes.

Severe Mitral Valve Regurgitation Secondary to Fulminant Myocarditis in the Setting of a Lupus Flare.

Systemic Lupus Erythematosus represents a chronic autoimmune disorder characterized by multiorgan involvement. Lupus myocarditis is a rare presentation of one of the cardiac complications of lupus with an incidence of 3-9%. It usually presents with non-specific symptoms such as dyspnea, orthopnea, chest pain, pedal edema, fever, diaphoresis, paroxysmal nocturnal dyspnea, nausea, vomiting, or palpitations. Even though endomyocardial biopsy is considered the gold standard diagnostic approach, other non-invasive diagnostic alternatives including cardiac magnetic resonance (CMR) have been studied. Therapeutic interventions may range from high-dose steroids, and IVIG, to the most advanced strategies such as mechanical circulatory support including VenoArterial Extracorporeal Membrane Oxygenation (VA-ECMO), and Impella, among others.

Preoperative Impella Therapy in Patients with Ventricular Septal Rupture and Cardiogenic Shock: Hemodynamic and Organ Function Outcomes.

OBJECTIVES: We examined the effects of preoperative Impella treatment on haemodynamic stability, organ recovery, and postoperative outcomes in patients with postinfarction ventricular septal rupture and cardiogenic shock. METHODS: Between April 2018 and February 2024, the data of 10 of 15 patients with postinfarction ventricular septal rupture and cardiogenic shock who underwent Impella therapy were analyzed. Urgent surgery was contingent on haemodynamic stability with Impella/ECpella, except in the presence of organ failure. We utilized a generalized linear mixed model to evaluate organ ischaemia through changes in blood parameters upon admission and at subsequent intervals post-Impella insertion. RESULTS: Preoperative Impella or combined Impella and ECpella (five patients each) support were provided, with diagnoses and surgeries occurring at an average of 4 days (interquartile range: 2-5) and 8 days (interquartile range: 2-14) after myocardial infarction, respectively. Treatment significantly reduced lactate, alanine aminotransferase, creatine kinase-MB, and troponin I levels (p ≤ 0.05 for all). Conversely, no significant change was noted in the aspartate aminotransferase level or estimated glomerular filtration rate. Hemoglobin and platelet counts decreased despite transfusions (p < 0.001). No surgical deaths occurred; however, 70% of the patients required prolonged mechanical ventilation and 80% were transferred for rehabilitation. CONCLUSIONS: Impella or ECpella treatment can improve haemodynamic and organ failure outcomes in postinfarction ventricular septal rupture and cardiogenic shock. However, the risks of prolonged support, including hemorrhagic events and the need for extended rehabilitation, point to a need for comparative studies to optimize support duration.

Prolonged Impella 5.0/5.5 support within different pathways of care for cardiogenic shock: the experience of a referral center.

Aims: Impella 5.0 and 5.5 are promising low-invasive left ventricle (LV) temporary mechanical circulatory supports (tMCS) for cardiogenic shock due to LV mechanical unloading and are paired with powerful hemodynamic support. This study aimed to analyze data and destinies of patients supported with Impella 5.0/5.5 at a national referral center for cardiogenic shock and to assess the parameters associated with myocardial recovery and successful weaning. Methods: A single-center observational study was conducted on all patients treated with Impella 5.0 or 5.5 from March 2018 to July 2023. Results: A total of 59 patients underwent Impella 5.0/5.5 implantation due to profound cardiogenic shock, with acute myocardial infarction being the most frequent cause of shock (42 patients, 71%). The median duration of Impella support was 13 days (maximum duration of 52 days). Axillary cannulation was feasible in almost all patients, and 36% were mobilized during support. A total of 44 patients (75%) survived to the next therapy/recovery: 21 patients experienced recovery and 15 and 8 were bridged to long-term LVAD and heart transplantation, respectively. The global survival rate was 66%. The predictors of native heart recovery at multivariate analysis were the number of days on tMCS before upgrade to Impella 5.0/5.5 [hazard ratio (HR) 0.68 (0.51-9) p = 0.0068] and improvement of LVEF within the first 7-10 days of support [HR 4.72 (1.34-16.7), p = 0.016]. Conclusions: Transcatheter systems such as Impella 5.0/5.5 revolutionized the field of tMCS. Myocardial recovery is the primary clinical target. Its prognostication and promotion are key to ensure the most proficuous course for each patient from cardiogenic shock to long-term event-free survival.

The Double Barrel Impella Exchange: A Reliable Method for Uninterrupted Mechanical Circulatory Support.

Classic Impella exchange interrupts flow when the old device is pulled into the aorta before advancing the new device across the aortic valve, threatening circulatory collapse and loss of left ventricular access. In "double barrel," uninterrupted Impella exchange, the new device is placed into the ventricle alongside the old, where flow is first transitioned completely. Of thirty-one consecutive patients undergoing this procedure, none experienced intraoperative cardiac arrest and 96.8% (30/31) had no new aortic insufficiency. One vascular complication ensued following known preoperative iliac injury. One patient suffered nonembolic stroke; another had subarachnoid hemorrhage. Fifty-five percent (17/31) of patients survived, with 22.6% (7/31) recovering, 25.8% (8/31) undergoing transplant, and 6.5% (2/31) transitioning to durable LVAD. Impella-only survival (83.3%, 10/12) was significantly higher than Impella-ECMO survival (36.8%, 7/19) (OR 14.46, 95% CI 1.74-119.93, p=0.01). We conclude "double barrel" technique is reliable in device-dependent cardiogenic shock patients, offering significant advantage and minimal risk.

Comparison of Intraoperative Blood Product Use During Heart Transplantation in Patients Bridged with Impella 5.5 versus Durable Left Ventricular Assist Devices.

OBJECTIVE: To determine if the intraoperative transfusion requirements differ based on the mechanical circulatory device used as a bridge to heart transplantation. DESIGN: A single-center retrospective analysis of intraoperative transfusion requirements in all patients undergoing heart or heart/kidney transplantation between November 2018 and July 2021 who were bridged with a temporary (Impella 5.5) or durable left ventricular assist device (LVAD). SETTING: A tertiary care hospital. PARTICIPANTS: Forty-three adult patients bridged to heart or heart/kidney transplantation with a temporary or durable LVAD between 2018 and 2021 INTERVENTIONS: Recording of baseline characteristics and intraoperative transfusion requirements, including packed red blood cells, fresh frozen plasma, cryoprecipitate, autologous blood salvage, and platelets. The difference in cardiopulmonary bypass times, intensive care unit length of stay, and the vasoactive inotrope score following transplantation were also recorded. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the volume of blood products transfused intraoperatively. Patients who underwent bridge to transplantation using the Impella 5.5 had statistically significant lower median transfusions of cryoprecipitate (155 mL versus 200 mL, p = 0.015), autologous blood salvage (675 mL versus 1,125 mL, p ≤ 0.01), and platelets (412 mL versus 675 mL, p ≤ 0.01). Additionally, there was a trend toward lower transfusion of intraoperative packed red blood cells (4.5 units versus 6.5 units, p = 0.29) and fresh frozen plasma (675 mL versus 800 mL, p = 0.11), but these were not statistically significant. CONCLUSIONS: The results suggest a reduction in certain intraoperative transfusion requirements in patients undergoing heart transplantation bridged with the Impella 5.5 versus durable left ventricular assist device.

Lower extremity artery thromboembolism during removal of Impella after repair for ventricular septal rupture: A case report.

Although the anticoagulant complications of Impella are well known, the timing of heparin administration when using Impella immediately after open heart surgery has not been established. We report a case of a 59-year-old man with Impella-assisted repair of a ventricular septal perforation after acute myocardial infarction who developed thromboembolism of the lower extremity arteries after removal of Impella.

Pathophysiology, diagnosis and management of right ventricular failure: A state of the art review of mechanical support devices.

The function of the right ventricle (RV) is to drive the forward flow of blood to the pulmonary system for oxygenation before returning to the left ventricle. Due to the thin myocardium of the RV, its function is easily affected by decreased preload, contractile motion abnormalities, or increased afterload. While various etiologies can lead to changes in RV structure and function, sudden changes in RV afterload can cause acute RV failure which is associated with high mortality. Early detection and diagnosis of RV failure is imperative for guiding initial medical management. Echocardiographic findings of reduced tricuspid annular plane systolic excursion (<1.7) and RV wall motion (RV S' <10 cm/s) are quantitatively supportive of RV systolic dysfunction. Medical management commonly involves utilizing diuretics or fluids to optimize RV preload, while correcting the underlying insult to RV function. When medical management alone is insufficient, mechanical circulatory support (MCS) may be necessary. However, the utility of MCS for isolated RV failure remains poorly understood. This review outlines the differences in flow rates, effects on hemodynamics, and advantages/disadvantages of MCS devices such as intra-aortic balloon pump, Impella, centrifugal-flow right ventricular assist devices, extracorporeal membrane oxygenation, and includes a detailed review of the latest clinical trials and studies analyzing the effects of MCS devices in acute RV failure.

Extracorporeal Life Support in Myocardial Infarction: New Highlights.

Background and Objectives: Cardiogenic shock (CS) is a potentially severe complication following acute myocardial infarction (AMI). The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) in these patients has risen significantly over the past two decades, especially when conventional treatments fail. Our aim is to provide an overview of the role of VA-ECMO in CS complicating AMI, with the most recent literature highlights. Materials and Methods: We have reviewed the current VA-ECMO practices with a particular focus on CS complicating AMI. The largest studies reporting the most significant results, i.e., overall clinical outcomes and management of the weaning process, were identified in the PubMed database from 2019 to 2024. Results: The literature about the use of VA-ECMO in CS complicating AMI primarily has consisted of observational studies until 2019, generating the need for randomized controlled trials. The EURO-SHOCK trial showed a lower 30-day all-cause mortality rate in patients receiving VA-ECMO compared to those receiving standard therapy. The ECMO-CS trial compared immediate VA-ECMO implementation with early conservative therapy, with a similar mortality rate between the two groups. The ECLS-SHOCK trial, the largest randomized controlled trial in this field, found no significant difference in mortality at 30 days between the ECMO group and the control group. Recent studies suggest the potential benefits of combining left ventricular unloading devices with VA-ECMO, but they also highlight the increased complication rate, such as bleeding and vascular issues. The routine use of VA-ECMO in AMI complicated by CS cannot be universally supported due to limited evidence and associated risks. Ongoing trials like the Danger Shock, Anchor, and Recover IV trials aim to provide further insights into the management of AMI complicated by CS. Conclusions: Standardizing the timing and indications for initiating mechanical circulatory support (MCS) is crucial and should guide future trials. Multidisciplinary approaches tailored to individual patient needs are essential to minimize complications from unnecessary MCS device initiation.

In Patients with Cardiogenic Shock, Extracorporeal Membrane Oxygenation Is Associated with Very High All-Cause Inpatient Mortality Rate.

Background: The goal of this study was to evaluate the effect of extracorporeal membrane oxygenation (ECMO) on mortality in patients with cardiogenic shock excluding Impella and IABP use. Method: The large Nationwide Inpatient Sample (NIS) database was utilized to study any association between the use of ECMO in adults over the age of 18 and mortality and complications with a diagnosis of cardiogenic shocks. Results: ICD-10 codes for ECMO and cardiogenic shock for the available years 2016-2020 were utilized. A total of 796,585 (age 66.5 ± 14.4) patients had a diagnosis of cardiogenic shock excluding Impella. Of these patients, 13,160 (age 53.7 ± 15.4) were treated with ECMO without IABP use. Total inpatient mortality without any device was 32.7%. It was 47.9% with ECMO. In a multivariate analysis adjusting for 47 variables such as age, gender, race, lactic acidosis, three-vessel intervention, left main myocardial infarction, cardiomyopathy, systolic heart failure, acute ST-elevation myocardial infarction, peripheral vascular disease, chronic renal disease, etc., ECMO utilization remained highly associated with mortality (OR: 1.78, CI: 1.6-1.9, p < 0.001). Evaluating teaching hospitals only revealed similar findings. Major complications were also high in the ECMO cohort. Conclusions: In patients with cardiogenic shock, the use of ECMO was associated with the high in-hospital mortality regardless of comorbid condition, high-risk futures, or type of hospital.

Investigations of Differential Hypoxemia During Venoarterial Membrane Oxygenation with and Without Impella Support.

PURPOSE: Venoarterial extracorporeal membrane oxygenation (VA ECMO) is used in patients with refractory cardiac or cardio-pulmonary failure. Native ventricular output interacts with VA ECMO flow and may hinder sufficient oxygenation to the heart and the brain. Further on, VA ECMO leads to afterload increase requiring ventricular unloading. The aim of the study was to investigate aortic blood flow and oxygenation for various ECMO settings and cannula positions with a numerical model. METHODS: Four different aortic cannula tip positions (ascending aorta, descending aorta, abdominal aorta, and iliac artery) were included in a model of a human aorta. Three degrees of cardiac dysfunction and VA ECMO support (50%, 75% and 90%) with a total blood flow of 6 l/min were investigated. Additionally, the Impella CP device was implemented under 50% support condition. Blood oxygen saturation at the aortic branches and the pressure acting on the aortic valve were calculated. RESULTS: A more proximal tip orientation is necessary to increase oxygen supply to the supra-aortic and coronary arteries for 50% and 75% support. During the 90% support scenario, proper oxygenation can be achieved independently of tip position. The use of Impella reduces afterload by 8-17 mmHg and vessel oxygenation is similar to 50% VA ECMO support. Pressure load on the aortic valve increases with more proximal tip position and is decreased during Impella use. CONCLUSIONS: We present a simulation model for the investigation of hemodynamics and blood oxygenation with various mechanical circulatory support systems. Our results underline the intricate and patient-specific relationship between extracorporeal support, cannula tip orientation and oxygenation capacity.

Clinical outcomes among cardiogenic shock patients supported with high-capacity Impella axial flow pumps: A report from the Cardiogenic Shock Working Group.

BACKGROUND: The Impella 5.0 and 5.5 pumps (Abiomed, Danvers, MA) are large-bore transvalvular micro-axial assist devices used in cardiogenic shock (CS) for patients requiring high-capacity flow. Despite their increasing use, real-world data regarding indications, rates of utilization and clinical outcomes with this therapy are limited. The objective of our study was to examine clinical profiles and outcomes of patients in a contemporary, real-world CS registry of patients who received an Impella 5.0/5.5 alone or in combination with other temporary mechanical circulatory support (tMCS) devices. METHODS: The CS Working Group (CSWG) Registry includes patients from 34 US hospitals. For this analysis, data from patients who received an Impella 5.0/5.5 between 2020-2023 were analyzed. Use of Impella 5.0/5.5 with or without additional tMCS therapies, duration of support, adverse events and outcomes at hospital discharge were studied. Adverse events including stroke, limb ischemia, bleeding and hemolysis were not standardized by the registry but reported per individual CSWG Primary Investigator discretion. For those who survived, rates of native heart recovery (NHR) or heart replacement therapy (HRT) including heart transplant (HT), or durable ventricular assist device (VAD) were recorded. We also assessed outcomes based on shock etiology (acute myocardial infarction or MI-CS vs. heart failure-related CS or HF-CS). RESULTS: Among 6,205 patients, 754 received an Impella 5.0/5.5 (12.1%), including 210 MI-CS (27.8%) and 484 HF-CS (64.1%) patients. Impella 5.0/5.5 was used as the sole tMCS device in 32% of patients, while 68% of patients received a combination of tMCS devices. Impella cannulation sites were available for 524/754 (69.4%) of patients, with 93.5% axillary configuration. Survival to hospital discharge for those supported with an Impella 5.0/5.5 was 67%, with 20.4% NHR and 45.5% HRT. Compared to HF-CS, patients with MI-CS supported on Impella 5.0/5.5 had higher in-hospital mortality (45.2% vs 26.2%, p < 0.001) and were less likely to receive HRT (22.4% vs 56.6%, p < 0.001. For patients receiving a combination of tMCS during hospitalization, this was associated with higher rates of limb ischemia (9% vs. 3%, p < 0.01), bleeding (52% vs 33%, p < 0.01), and mortality (38% vs 25%; p < 0.001) compared to Impella 5.0/5.5 alone. Among Impella 5.0/5.5 recipients, the median duration of pump support was 12.9 days (IQR: 6.8-22.9) and longer in patients bridged to HRT (14 days; IQR: 7.7-28.4). CONCLUSIONS: In this multi-center cohort of patients with CS, use of Impella 5.0/5.5 was associated with an overall survival of 67.1% and high rates of HRT. Lower adverse event rates were observed when Impella 5.0/5.5 was the sole support device used. Further study is required to determine whether a strategy of early Impella 5.0/5.5 use for CS improves survival. CONDENSED ABSTRACT: High capacity Impella heart pumps are capable of provide up to 5.5 liter/min of flow while upper body surgical placement allows for ambulation. Patients with advanced cardiogenic shock from acute myocardial infarction or heart failure requiring temporary mechanical circulatory support may benefit from upfront use of Impella 5.5 to improve overall survival, including native heart recovery or successful bridge to durable left ventricular assist device surgery or heart transplantation.

Left ventricular unloading therapy using Impella 5.5 after emergency surgery for acute myocardial infarction mechanical complication: a case report.

BACKGROUND: Following an acute myocardial infarction (AMI), surgery for left ventricular free wall rupture (LVFWR) and ventricular septal rupture (VSR) has a high in-hospital mortality rate, which has not improved significantly over time. Unloading the LV is critical to preventing excessive stress on the repair site and avoiding problems such as bleeding, leaks, patch dehiscence, and recurrence of LVFWR and VSR because the tissue is so fragile. We present two cases of patients who used Impella 5.5 for LV unloading following emergency surgery for AMI mechanical complications. CASE PRESENTATION: A 76-year-old male STEMI patient underwent fibrinolysis of the distal right coronary artery. Three days later, he passed out and went into shock. Echocardiography revealed a cardiac tamponade. We found an oozing-type LVFWR on the posterolateral wall and treated it with a non-suture technique using TachoSil. Before the patient was taken off CPB, Impella 5.5 was inserted into the LV via a 10 mm synthetic graft connected to the right axillary artery. We kept the flow rate above 4.0 to 4.5 L/min until POD 3 to reduce LV wall tension while minimizing pulsatility. On POD 6, we weaned the patient from Impella 5.5. A postoperative cardiac CT scan showed no contrast leakage from the LV. However, a cerebral hemorrhage on POD 4 during heparin administration complicated his hospitalization. Case 2: A diagnosis of cardiogenic shock caused by STEMI occurred in an 84-year-old male patient, who underwent PCI of the LAD with IABP support. Three days after PCI, echocardiography revealed VSR, and the patient underwent emergency VSR repair with two separate patches and BioGlue applied to the suture line between them. Before weaning from CPB, we implanted Impella 5.5 in the LV and added venoarterial extracorporeal membrane oxygenation (VA-ECMO) support for right heart failure. The postoperative echocardiography revealed no residual shunt. CONCLUSIONS: Patients undergoing emergency surgery for mechanical complications of AMI may find Impella 5.5 to be an effective tool for LV unloading. The use of VA-ECMO in conjunction with Impella may be an effective strategy for managing VSR associated with concurrent right-sided heart failure.

Hemodynamics with mechanical circulatory support devices using a cardiogenic shock model.

Mechanical circulatory support (MCS) devices, including veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and Impella, have been widely used for patients with cardiogenic shock (CS). However, hemodynamics with each device and combination therapy is not thoroughly understood. We aimed to elucidate the hemodynamics with MCS using a pulsatile flow model. Hemodynamics with Impella CP, VA-ECMO, and a combination of Impella CP and VA-ECMO were assessed based on the pressure and flow under support with each device and the pressure-volume loop of the ventricle model. The Impella CP device with CS status resulted in an increase in aortic pressure and a decrease in end-diastolic volume and end-diastolic pressure (EDP). VA-ECMO support resulted in increased afterload, leading to a significant increase in aortic pressure with an increase in end-systolic volume and EDP and decreasing venous reservoir pressure. The combination of Impella CP and VA-ECMO led to left ventricular unloading, regardless of increase in afterload. Hemodynamic support with Impella and VA-ECMO should be a promising combination for patients with severe CS.

Left ventricular unloading via percutaneous assist device during extracorporeal membrane oxygenation in acute myocardial infarction and cardiac arrest.

INTRODUCTION: A feared complication of an acute myocardial infarction (AMI) is cardiac arrest (CA). Even if return of spontaneous circulation is achieved, cardiogenic shock (CS) is common. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) supports patients with CS and is often used in conjunction with an Impella device (2.5 and CP) to off-load the left ventricle, although limited evidence supports this approach. METHODS: The goal of this study was to determine whether a mortality difference was observed in VA-ECMO alone versus VA-ECMO with Impella (ECPELLA) in patients with CS from AMI and CA. A retrospective chart review of 50 patients with AMI-CS and CA and were supported with VA-ECMO (n = 34) or ECPELLA (n = 16) was performed. The primary outcome was all-cause mortality at 6-months from VA-ECMO or Impella implantation. Secondary outcomes included in-hospital mortality and complication rates between both cohorts and intensive care unit data. RESULTS: Baseline characteristics were similar, except patients with ST-elevation myocardial infarction were more likely to be in the VA-ECMO group (p = 0.044). The ECPELLA cohort had significantly worse survival after VA-ECMO (SAVE) score (p = 0.032). Six-month all-cause mortality was not significantly different between the cohorts, even when adjusting for SAVE score. Secondary outcomes were notable for an increased rate of minor complications without an increased rate of major complications in the ECPELLA group. CONCLUSIONS: Randomized trials are needed to determine if a mortality difference exists between VA-ECMO and ECPELLA platforms in patients with AMI complicated by CA and CS.

Automated control of Impella maintains optimal left ventricular unloading during periods of unstable hemodynamics and prevents myocardial damage in acute myocardial infarction.

BACKGROUND: Left ventricular (LV) unloading by Impella, an intravascular microaxial pump, has been shown to exert dramatic cardioprotective effects in acute clinical settings of cardiovascular diseases. Total Impella support (no native LV ejection) is far more efficient in reducing LV energetic demand than partial Impella support, but the manual control of pump speed to maintain stable LV unloading is difficult and impractical. We aimed to develop an Automatic IMpella Optimal Unloading System (AIMOUS), which controls Impella pump speed to maintain LV unloading degree using closed-feedback control. We validated the AIMOUS performance in an animal model. METHODS: In dogs, we identified the transfer function from pump speed to LV systolic pressure (LVSP) under total support conditions (n = 5). Using the transfer function, we designed the feedback controller of AIMOUS to keep LVSP at 40 mmHg and examined its performance by volume perturbations (n = 9). Lastly, AIMOUS was applied in the acute phase of ischemia-reperfusion in dogs. Four weeks after ischemia-reperfusion, we assessed LV function and infarct size (n = 10). RESULTS: AIMOUS maintained constant LVSP, thereby ensuring a stable LV unloading condition regardless of volume withdrawal or infusion (±8 ml/kg from baseline). AIMOUS in the acute phase of ischemia-reperfusion markedly improved LV function and reduced infarct size (No Impella support: 13.9 ± 1.3 vs. AIMOUS: 5.7 ± 1.9%, P < 0.05). CONCLUSIONS: AIMOUS is capable of maintaining optimal LV unloading during periods of unstable hemodynamics. Automated control of Impella pump speed in the acute phase of ischemia-reperfusion significantly reduced infarct size and prevented subsequent worsening of LV function.

Impella Versus Non-Impella for Nonemergent High-Risk Percutaneous Coronary Intervention.

The benefit of mechanical circulatory support with Impella (Abiomed, Inc., Danvers, Massachusetts) for high-risk percutaneous coronary intervention (HR-PCI) is uncertain. PROTECT III registry data showed improved outcomes with Impella compared with historical data (PROTECT II) but lacks a direct comparison with the HR-PCI cohort without Impella support. We retrospectively identified patients meeting the PROTECT III inclusion criteria for HR-PCI and compared this group (non-Impella cohort [NonIMP]) with the outcomes data from the PROTECT III registry (Impella cohort). Baseline differences were balanced using inverse propensity weighting. The coprimary outcome was major adverse cardiac events (MACE) in-hospital and at 90 days. A total of 283 patients at great risk did not receive Impella support; 200 patients had 90-days event ascertainment and were included in the inverse propensity weighting analysis and compared with 504 patients in the Impella cohort group. After calibration, few residual differences remained between groups. The primary outcome was not different in-hospital (3.0% vs 4.8%, p = 0.403) but less in NonIMP at 90 days (7.5% vs 13.8%, p = 0.033). Periprocedural vascular complications, bleeding, and transfusion rate did not differ between groups; however, acute kidney injury occurred more frequently in the NonIMP group (10.5% vs 5.4%, p = 0.023). In conclusion, under identical HR-PCI inclusion criteria for Impella use in PROTECT III, an institutional non-Impella-supported HR-PCI cohort showed similar MACE in-hospital but fewer MACE at 90 days, whereas there was no signal for periprocedural harm with Impella use. These results do not support routine usage of Impella for patients with HR-PCI.