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Trial Overview

The SHIELD II (Coronary InterventionS in HIgh-Risk PatiEnts Using a Novel Percutaneous Left Ventricular Support Device) U.S. IDE Clinical Trial is a prospective, randomized, multi-center, open-label study comparing HeartMate PHP™ (Percutaneous Heart Pump) to the Impella® 2.5 in patients undergoing high-risk percutaneous coronary intervention (PCI). The study will randomize up to 425 patients. Researchers at up to 60 sites may immediately begin randomization after training and will evaluate HeartMate PHP for non-inferiority to the Impella® 2.5.


PHP Canula Impeller

HeartMate PHP is a low-profile acute catheter-based heart pump designed to disrupt the traditional relationship between size and flow in catheter-based support devices.* It is capable of generating near–physiological mean blood flow of 4-5 L/min following delivery through a true percutaneous insertion. The device has also been designed for hemocompatibility, with operating speeds of 16,000-20,500 RPM.33


  • High blood flow: the covered nitinol cannula and integrated impeller expand from a low 13F insertion profile to 24F once across the aortic valve for near–physiological mean flow of over 4 L/min.33
  • Rapidly inserted and stable over time: radiopaque distal markers ensure accurate placement, and the flexible catheter with variable stiffness accommodates heart motion and increases stability over the aortic arch. HeartMate PHP provides hemodynamic support in minutes.
  • Designed for hemocompatibility: the efficient 3-blade impeller is designed to minimize shear stress on blood moving through the device.34 Heartmate PHP achieves high flow rates at operating speeds as low as 16,000 RPM.33
  • Durable internal driveline: the internal driveline is constructed of 10 interwoven microcables, ensuring maximum durability in tortuous anatomy.34

How It Works

The HeartMate PHP catheter is inserted over a guide wire into the femoral artery via a 14F introducer sheath. Once positioned across the aortic valve, the outer sheath of the PHP is retracted, fully expanding the cannula to 24F. As the integrated 3-blade impeller begins to spin, blood is pulled into the cannula from the left ventricle and is pumped into the ascending aorta. The wide 24F expandable cannula and low operating speeds of 16,000-20,500 RPM minimize shear stress on the blood and provide hemodynamic support in minutes.

Primary Study Objective

To evaluate the safety and effectiveness of HeartMate PHP by demonstrating non-inferiority to the Impella® 2.5 when supporting patients with severe symptomatic coronary artery disease with diminished but stable cardiovascular function. Patients must be undergoing elective or urgent high-risk PCI, but are not candidates for coronary artery bypass graft (CABG) surgery.

Study Population

Patients undergoing high-risk PCI.

Primary Endpoint

Composite primary endpoint at 90 days of:

  • Cardiac death
  • Myocardial infarction
  • Stroke
  • Repeat revascularization (PCI or CABG)
  • Bleeding (BARC 3 or 5)
  • Aortic insufficiency +2 degrees over baseline
  • Severe hypotension, defined as systolic blood pressure <90 mmHg while on device support requiring inotropic/pressor medications to restore hemodynamics

Secondary Study Endpoints

Individual components of the composite primary endpoint

  • All death
  • Maximal change in the following hemodynamic measures from baseline:
    1. Cardiac power output (CPO)
    2. Central venous pressure (CVP)
    3. Mean arterial pressure (MAP)
    4. Pulmonary artery pressure (PAP)
    5. Pulmonary capillary wedge pressure (PCWP)
    6. Cardiac output (CO)
    7. Cardiac index (CI)
  • Device-related access site complication requiring intervention or device-related limb ischemia
  • Surgical intervention due to device complication or malfunction
  • Duration of hospital stay
  • Intensive care unit (ICU) days

Study Duration

90 days post–device removal.

To learn more about the SHIELD II Trial, go to: Identifier: NCT02468778

*U.S.: Caution: Investigational Device: Limited by Federal United States law to investigational use.

Impella® is a registered trademark of Abiomed.

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