Overview
Clinical Frame
An LVAD patient with tea coloured urine, a new low flow alarm, or a sustained rise in pump power may have a time critical haemocompatibility problem.
An LVAD patient with tea-coloured urine, a new low-flow alarm, or a sustained rise in pump power may have a time-critical haemocompatibility problem. The first clinical question is not simply whether the INR is low; it is whether blood is being destroyed, flow is obstructed, perfusion is failing, or an embolic event has occurred. Intrinsic pump thrombosis is one explanation, but it is not the only one. Outflow graft obstruction, inflow cannula malposition, infection, hypertension, low-flow states, and non-device causes of haemolysis can produce overlapping findings. This distinction matters especially with the HeartMate 3, in which de novo pump thrombosis is now uncommon. Canadian VAD programmes generally use ISHLT guidance and centre-specific protocols because Canadian Cardiovascular Society guidance addresses advanced-heart-failure referral and mechanical-support selection rather than a dedicated pump-thrombosis algorithm.