Determination of cardiac parameters for modulation of blood pump support

Inventors

Moyer, Christian • Corbett, Scott C. • El Katerji, Ahmad • Weber, David

Assignees

Abiomed Inc

Abstract

The systems, devices, and methods presented herein use a blood pump to obtain measurements of cardiac function. The system can quantify the functioning of the native heart by measuring certain parameters/signals such as aortic pressure or motor current, then calculate and display one or more cardiac parameters and heart function parameters, such as left ventricular pressure, left ventricular end diastolic pressure, or cardiac power output. These parameters provide valuable information to a user regarding current cardiac function, as well as positioning and function of the blood pump. In some embodiments, the system can act as a diagnostic and therapeutic tool. Providing cardiac parameters in real-time, along with warnings about adverse effects and recommendations to support cardiac function, such as increasing or decreasing the volumetric flow rate of blood pumped by the device, administering pharmaceutical therapies, and/or repositioning the blood pump allow clinicians to better support and treat cardiovascular disease.

Core Innovation

The invention provides a system for providing cardiac support to a heart using a blood pump configured to be positioned in a heart. The blood pump includes a cannula and a motor operable at a motor speed that draws variable motor current to provide a level of cardiac support. A controller measures an aortic pressure and measures the motor current to determine a pressure gradient across the cannula associated with the motor current.

From the measured aortic pressure and the pressure gradient across the cannula associated with the motor current, the controller calculates a cardiac parameter, records the calculated cardiac parameter in memory, and determines based on the calculated cardiac parameter a heart function parameter. The controller displays at least one of the calculated cardiac parameter or the heart function parameter, and determines a problem with positioning of the blood pump in at least one configuration.

Based on the calculated cardiac parameter and the heart function parameter, the controller determines at least one of a recommended change to the motor speed, a recommended therapy including administration of a therapeutic substance or medication, and/or a recommended change to a level of support. In additional configurations, the controller compares at least one of the calculated cardiac parameter or the heart function parameter to a first threshold and triggers an alarm if the threshold is satisfied.

In bi-ventricular arrangements, the controller measures aortic pressure and first and second motor currents, determines first and second pressure gradients across first and second cannulas, calculates first and second cardiac parameters, determines at least one heart function parameter, and determines and displays a recommended change to maintain balance in left-side and right-side support.

Claims Coverage

The independent claims set out a core diagnostic-and-control architecture with multiple inventive features: deriving a pressure gradient from motor current, calculating a cardiac parameter from aortic pressure and the pressure gradient, deriving a heart function parameter from the cardiac parameter, and using the derived metrics to detect positioning problems, display parameters, recommend support or therapy changes, adjust motor speed based on user input, and trigger threshold-based alarms. Across the independent claims, the main inventive features differ by whether they focus on positioning problem detection, motor-speed recommendation with user input, therapy recommendation with therapeutic substance or medication, bi-ventricular balance, or threshold-triggered alarms.

Across the independent claims, the central claim coverage feature is computing pressure-gradient-based cardiac parameters from measured aortic pressure and motor current, converting those parameters into a heart function parameter, and then using the derived metrics to drive output, action, and safety behavior. The independent claims further partition the system into configurations for positioning problem detection, therapy recommendation with therapeutic substance or medication administration, bi-ventricular left/right support balancing, and threshold-based alarms.

Stated Advantages

Documented Applications