CardioQuip, LLC manufactured cardiac heater-cooler devices that underwent significant design and component modifications since their original 510(k) clearance in 2010, including the addition of an airflow hood, dripless external hose kit, and thermoelectric cooling technology, without obtaining the required new clearances or demonstrating substantial equivalence. The company failed to comply with Current Good Manufacturing Practice (CGMP) and Quality System Regulation (QSR) requirements, and the modifications to the device design, components, and manufacturing methods constituted significant changes that should have triggered new premarket notification submissions under 21 CFR 807.81(a)(3). An FDA investigator documented these violations during an inspection conducted from August 19 through September 17, 2021 at the firm's College Station, Texas facility.