Clinical Courses of HeartMate II Left Ventricular Assist Device Thrombosis

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Device Technology

Background:

• Left ventricular assist devices (LVADs) are critical for end-stage heart failure.
• Device thrombosis is a significant complication impacting LVAD performance and patient outcomes.
• Distinct clinical presentations of LVAD thrombosis necessitate a standardized classification system.

Purpose of the Study:

• To identify and classify temporal patterns of HeartMate II LVAD thrombosis.
• To compare patient characteristics and clinical outcomes across different thrombosis patterns.
• To propose a nomenclature for LVAD thrombosis classification.

Main Methods:

• Retrospective review of 362 HeartMate II devices implanted between October 2008 and July 2014.
• Categorization of 19 confirmed device thromboses into three patterns: abrupt, subacute, and asymptomatic hemolysis.
• Analysis of patient demographics, clinical variables, and outcomes for each thrombosis pattern.

Main Results:

• Three distinct patterns of LVAD thrombosis were identified: Type 1 (abrupt), Type 2 (subacute), and Type 3 (asymptomatic hemolysis).
• Abrupt thrombosis (Type 1) presented acutely around 56.5 days post-implantation, with patients in New York Heart Association functional class III or IV.
• No significant differences in mortality or need for surgical intervention were observed across the three patterns; however, asymptomatic hemolysis was associated with prior cardiac thrombi and bacteremia.

Conclusions:

• Confirmed LVAD thrombosis exhibits diverse temporal patterns with unique clinical manifestations.
• The proposed classification system aids in understanding the varied presentations of LVAD thrombosis.
• Recognizing these patterns is essential for tailored patient management and improved outcomes in LVAD therapy.