Left Ventricular Assist Device Inflow Angle and Pump Positional Change Over Time Adverse Impact on Left Ventricular...

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Medical Device Technology

Background:

• Investigates left ventricular assist device (LVAD) inflow cannula angulation and pump positional changes.
• Examines the incidence of thrombotic pump dysfunction in HeartMate II (HM2) patients.

Purpose of the Study:

• To analyze the relationship between LVAD inflow cannula angulation, pump position changes, and pump dysfunction.
• To identify factors contributing to HeartMate II pump dysfunction in a large patient cohort.

Main Methods:

• Retrospective review of 326 primary HM2 LVAD patients (2008-2013).
• Comparison of patients who underwent pump exchange (PE) for dysfunction, had pump dysfunction (PD) without exchange, and had normal function (NL).
• Measurement of inflow cannula (IL) angle and pump positional change from chest radiographs at multiple time points.

Main Results:

• Significant differences in IL angle were observed between PE and NL groups at all measured time points (p < 0.05).
• Sixty-seven percent of the PE group experienced pump positional change, compared to 36% in the NL group (p=0.019).
• A majority of patients with positional change or acute angulation did not develop pump dysfunction.

Conclusions:

• Pump positional change is a potential contributor to LVAD dysfunction or failure.
• Pump positional change does not solely account for all observed LVAD pump dysfunction or failure.