Exercise Tolerance in Patients With Implanted Left Ventricular Assist Device

Karol Wierzbicki22 enrolled

Overview

To evaluate the concept of dynamic pump speed optimization based on the echocardiographic assessment of aortic valve opening during cardiopulmonary exercise test.

Left ventricular assist devices (LVAD) are becoming a destination therapy in patients with end-stage left ventricular dysfunction. Current generation pumps operate with a fixed rotation speed without the capability of automated speed adjustment. It was shown that acceleration of the pump speed during stress test increases the maximum exercise tolerance. Periodic aortic valve opening (AVO) is used to set up an optimal resting pump speed. The study aimed to evaluate the concept of dynamic pump speed optimization based on the echocardiographic assessment of AVO during the cardiopulmonary exercise test (CPET). Patients with implanted third-generation LVADs with hydrodynamic bearing (HVAD, Medtronic, MN, USA) are prospectively enrolled. Two CPETs are performed after resting speed optimization. The first one with maintained baseline pump speed settings, and the second one with gradually increased speed depending on live echocardiographic imaging. The sequence of tests is random.

Study Type

INTERVENTIONAL

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

NONE

Enrollment

Conditions

Left Ventricular Assist Device

Interventions

Cardiopulmonary exercise tests with maintained baseline optimal pump speed settings.OTHER

Optimal resting LVAD speed settings is defined as periodic aortic valve opening while maintaining the central position of the intraventricular septum, minimizing mitral regurgitation, and preserving the mean systemic blood pressure above 65 mmHg. The aim is to achieve an aortic valve opening ratio of around 25-33% by changing the pump speed at resting conditions.

Cardiopulmonary exercise test with gradually increased pump speed depending on live echocardiographic imaging.OTHER

During the modified speed exercise, when the aortic valve opening ratio rises above 50%, the pump speed is increased by 100 revolutions per minute (RPM). As the aortic valve remains closed the RPM is lowered by 100. Speed increment is not greater than 100 RPM per 45 seconds to enable an echocardiographic analysis of resulting changes and prevent suction events. There is no determined target speed, neither per time period nor maximal.

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients with implanted cardioverter-defibrillator and third-generation centrifugal CF-LVAD with hydrodynamic bearing (HVAD, Medtronic, Minnesota, United States), at least three months after surgery. Exclusion Criteria: * Hemodynamic instability. * Non-therapeutic anticoagulation. * Device or intracardiac thrombus. * Inflammation. * Active bleeding.

Locations (1)

John Paul II Hospital

Krakow, Lesser Poland Voivodeship, Poland