OPTIMIZE 5.5 - Optimizing Impella 5.5 Outcomes Through Advanced Data Science (OPTIMIZE)

May 27, 2026 updated by: Thomas Schlöglhofer, PhD, MSc, Medical University of Vienna

Clinical Outcomes and Adverse Events Associated With Microaxial Flow Pump Support: An Explorative Retrospective Study

The main goal of this observational, study is to develop a clinical decision support tool utilizing Impella 5.5 pump parameters to predict native heart recovery and prevent adverse events, by leveraging data science and real-world clinical data of cardiogenic shock patients.

Therefore, secondary objectives are essential to consolidating a retrospective longitudinal analysis of Impella 5.5 pump data alongside ICU digital health record datasets to:

  1. Validate the Impella 5.5 placement signal by comparing it with ICU arterial line waveforms.
  2. Integrate pump data with ICU clinical data to identify patterns associated with therapy outcomes, including native heart recovery, heart replacement therapy, and mortality while on device support.
  3. Define clinical scenarios linked to hemolysis, HRAEs, and arrhythmias and develop predictive models to mitigate their occurrence.

Study Overview

Detailed Description

The clinical management of patients experiencing severe cardiogenic shock requires precise, real-time monitoring to optimize hemodynamic support and guide therapeutic transitions. The Impella 5.5 micro-axial flow pump provides left ventricular unloading, generating automated internal continuous parameters that reflect moving cardiac states. This study establishes a retrospective, longitudinal framework that integrates these high-frequency device metrics with corresponding clinical data housed within intensive care unit (ICU) digital health records (DHR). By synthesizing these disparate data streams, this research aims to build an advanced analytical framework to support clinical decisions in the cardiogenic shock landscape.

Signal Validation and Data Preprocessing:

The initial phase of the study validates the physiological fidelity of the continuous data stream. High-frequency digital logs generated by the pump console-specifically the optical placement signal-will undergo time-series alignment with standard physiological waveforms recorded in the ICU, using indwelling arterial line pressure data as the reference standard. This signal validation ensures that the longitudinal parameter data accurately capture mechanical positioning and true left ventricular dynamics prior to entering the downstream modeling pipeline.

Analytical Framework and Modeling Strategy:

Following data integration and signal validation, the consolidated dataset will be leveraged to develop predictive models aimed at distinguishing patient trajectories and forecasting complications. The computational pipeline is divided into two primary analytical pathways:

Endpoint Classification:

An artificial neural network will be developed to evaluate patient trajectories toward distinct clinical endpoints: native heart recovery, escalation to heart replacement therapy, or death. The modeling pipeline incorporates a rigorous framework to ensure generalizability and guard against overfitting. The complete dataset will be partitioned into an 80% development subset and a 20% independent testing subset. The development subset will undergo 5-fold cross-validation to drive comprehensive model architecture optimization, systematically testing structural variations to identify the highest-performing network configuration.

Adverse Event Forecasting:

Separate statistical and machine learning architectures will be constructed to evaluate risk patterns and clinical scenarios associated with severe on-device complications, specifically clinical hemolysis, new-onset arrhythmias, and hemocompatibility-related adverse events (HRAEs). These models focus on identifying early-warning clusters within the high-frequency pump log data to identify sub-clinical changes before manifest physiological degradation occurs.

Through these combined pathways, this observational study seeks to lay the foundational algorithmic groundwork for a real-time clinical decision support tool utilizing objective, automated device analytics to improve safety and personalization in mechanical circulatory support.

Study Type

Observational

Enrollment (Estimated)

100

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

The study population comprises adult patients admitted to the intensive care unit (ICU) presenting with severe cardiogenic shock who required temporary mechanical circulatory support between January 2019 and March 2026, treated at the Medical University of Vienna, Austria. Eligible individuals are those who undergo clinical management utilizing the Impella 5.5 micro-axial flow pump as part of their standard of care. Only patients with available high-resolution pump data (downloaded from the clinical console) and ICU digital health record datasets extracted from ICCA (IntelliSpace Critical Care and Anesthesia, Philips Medical Systems Development and Manufacturing Centre, Hamburg, Germany) will be included for analysis.

Description

Inclusion Criteria:

  • Adult patients who were treated for cardiogenic shock and supported with an Impella 5.5 micro-axial flow pump
  • Only patients with available high-resolution pump data (downloaded from the clinical console) and ICU digital health record datasets

Exclusion Criteria:

  • Patients supported with an Impella 5.5 for indications other than cardiogenic shock (e.g., protected PCI or CABG)
  • Patients younger than 18 years
  • Patients with incomplete data, procedural records, or demographic information

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
Native heart recovery
Patients supported with the Impella 5.5 device (J&J MedTech) achieving native heart recovery
Temporary circulatory support using the Impella 5.5 micro-axial flow pump. The device is surgically placed (typically via the axillary artery) across the aortic valve into the left ventricle to provide active forward flow, unloading the left ventricle and maintaining systemic perfusion during cardiogenic shock. Management of the device includes the collection and analysis of continuous device-derived hemodynamic data and associated clinical parameters throughout the duration of support.
Heart replacement therapy (durable MCS or HTX)
Patients supported with the Impella 5.5 device (J&J MedTech) transitioning to heart replacement therapy (durable mechanical circulatory support or heart transplantation
Temporary circulatory support using the Impella 5.5 micro-axial flow pump. The device is surgically placed (typically via the axillary artery) across the aortic valve into the left ventricle to provide active forward flow, unloading the left ventricle and maintaining systemic perfusion during cardiogenic shock. Management of the device includes the collection and analysis of continuous device-derived hemodynamic data and associated clinical parameters throughout the duration of support.
All-cause mortality
Patients supported with the Impella 5.5 device (J&J MedTech) suffering from all-cause mortality during mechanical circulatory support.
Temporary circulatory support using the Impella 5.5 micro-axial flow pump. The device is surgically placed (typically via the axillary artery) across the aortic valve into the left ventricle to provide active forward flow, unloading the left ventricle and maintaining systemic perfusion during cardiogenic shock. Management of the device includes the collection and analysis of continuous device-derived hemodynamic data and associated clinical parameters throughout the duration of support.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Predictive Performance and Optimization of the Clinician Decision Support Tool
Time Frame: From the time of Impella 5.5 insertion up to device explant (estimated average of 5 to 14 days).

The predictive performance of the developed clinical decision support tool will be evaluated by its ability to classify patient trajectories toward native heart recovery versus adverse outcomes. The model will undergo comprehensive model architecture optimization to identify the structural configuration that yields optimal performance.

Model training, validation, and testing will follow a standard data split: 80% of the dataset will be utilized for training and internal validation using 5-fold cross-validation, and the remaining 20% will be held out as a definitive testing dataset.

Final classification performance will be quantified using specific metrics derived from Receiver Operating Characteristic (ROC) curve analysis, including: Area Under the Curve (AUC), Sensitivity, Specificity

From the time of Impella 5.5 insertion up to device explant (estimated average of 5 to 14 days).

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Bias Between the Impella 5.5 Placement Signal and ICU Arterial Line Waveforms
Time Frame: Continuously through the duration of active Impella 5.5 device support (from device insertion up to explant, estimated average of 5 to 14 days).

The systematic difference (bias) between the automated Impella 5.5 optical placement signal and the gold-standard ICU indwelling arterial line pressure waveforms will be quantified using Bland-Altman analysis to evaluate signal alignment.

Unit of Measure: Millimeters of mercury (mmHg)

Continuously through the duration of active Impella 5.5 device support (from device insertion up to explant, estimated average of 5 to 14 days).
Correlation Coefficient Between the Impella 5.5 Placement Signal and ICU Arterial Line Waveforms
Time Frame: Continuously through the duration of active Impella 5.5 device support (from device insertion up to explant, estimated average of 5 to 14 days).

The strength and direction of the linear relationship between the continuous time-series data of the Impella 5.5 optical placement signal and the ICU arterial line waveforms will be evaluated.

Unit of Measure: Correlation coefficient (r) on a scale from -1.0 to 1.0.

Continuously through the duration of active Impella 5.5 device support (from device insertion up to explant, estimated average of 5 to 14 days).
Concordance Rate of Directional Trends Between the Impella 5.5 Placement Signal and ICU Arterial Line Waveforms
Time Frame: Continuously through the duration of active Impella 5.5 device support (from device insertion up to explant, estimated average of 5 to 14 days).

The trending ability of the placement signal will be assessed via concordance plots. The concordance rate represents the percentage of data points where the directional change (increase or decrease) matches between both signal streams over time, excluding zones of clinical noise.

Unit of Measure: Percentage (%) of concordant data pairs.

Continuously through the duration of active Impella 5.5 device support (from device insertion up to explant, estimated average of 5 to 14 days).
Percentage of Participants Exhibiting Specific Device-Support Clinical Endpoints
Time Frame: Through the duration of hospital stay (estimated average of 30 days).

The final clinical trajectory of the cohort on device support will be categorized into one of three mutually exclusive outcomes:

  1. Native heart recovery (successful device weaning and explant)
  2. Escalation to heart replacement therapy (durable LVAD implantation or heart transplantation)
  3. All-cause mortality while on active device support.

Unit of Measure: Percentage (%) of participants within each categorical outcome category.

Through the duration of hospital stay (estimated average of 30 days).
Percentage of Participants Experiencing Device-Related Hemolysis
Time Frame: From device insertion up to 30 days post-explant or hospital discharge, whichever occurs first.

The incidence of clinically significant hemolysis on device support, defined by standard laboratory criteria (e.g., plasma free hemoglobin greater than 40 mg/dL or a doubling of lactate dehydrogenase alongside clinical signs).

Unit of Measure: Percentage (%) of participants.

From device insertion up to 30 days post-explant or hospital discharge, whichever occurs first.
Percentage of Participants Experiencing New-Onset Clinically Significant Arrhythmias
Time Frame: From device insertion up to 30 days post-explant or hospital discharge, whichever occurs first.

The incidence of new-onset atrial or ventricular arrhythmias occurring during device support that require immediate pharmacological, electrical, or device-setting intervention.

Unit of Measure: Percentage (%) of participants.

From device insertion up to 30 days post-explant or hospital discharge, whichever occurs first.
Number of Hemocompatibility-Related Adverse Events (HRAEs) Per Participant
Time Frame: From device insertion up to 30 days post-explant or hospital discharge, whichever occurs first.

The rate of hemocompatibility-related adverse events, including major bleeding episodes (requiring transfusion or reoperation) and thromboembolic events (e.g., ischemic stroke, peripheral arterial embolization) occurring during device support.

Unit of Measure: Number of events per participant.

From device insertion up to 30 days post-explant or hospital discharge, whichever occurs first.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Thomas Schlöglhofer, PhD, MSc, Medical University of Vienna

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

May 8, 2026

Primary Completion (Estimated)

January 8, 2029

Study Completion (Estimated)

May 30, 2029

Study Registration Dates

First Submitted

May 21, 2026

First Submitted That Met QC Criteria

May 27, 2026

First Posted (Actual)

June 1, 2026

Study Record Updates

Last Update Posted (Actual)

June 1, 2026

Last Update Submitted That Met QC Criteria

May 27, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

IPD will not be shared because the dataset contains highly sensitive, high-frequency physiological data linked with intensive care health records. Further, IPD is currently not planned for public sharing as the dataset is being actively used to develop a proprietary clinical decision support tool and model architecture optimization.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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