Appendix Table.

Definitions of clinically significant acute AEs within the first 60 days post-VAD implantation.

Event Type	Definition
CARDIAC/VASCULAR
Arrhythmia (ventricular or atrial)	Ventricular or atrial arrhythmia resulting in a clinical compromise (e.g., diminished VAD outflow, oligouria, pre-syncope or syncope) that requires hospitalization or occurs during the hospital stay. Ventricular arrhythmia: Sustained ventricular arrhythmia requiring defibrillation or cardioversion Atrial arrhythmia: Sustained supraventricular arrhythmia requiring drug treatment or cardioversion
Tamponade	Accumulation of fluid or clot in the pericardial space that requires surgical intervention or percutaneous catheter drainage.
RV Failure	Symptoms and signs of persistent right ventricular dysfunction (CVP >18mmHg with cardiac index <2.0 L/min/m² in the absence of elevated left atrial/pulmonary capillary wedge pressure (>18mmHg) tamponade, ventricular arrhythmias or pneumothorax) requiring RVAD implantation.
Thromboembolism (arterial or venous)	Arterial thromboembolism: Acute systemic arterial perfusion deficit in any non- cerebrovascular organ system confirmed by clinical and lab findings, operative or autopsy Venous thromboembolism: Evidence deep vein thrombosis or other venous thrombotic event.
Hemolysis	Plasma free hemoglobin >40mg/dl in association with clinical signs of hemolysis occurring within the first 72 hours post-implantation.
OTHER ORGAN SYSTEMS
Respiratory (tracheostomy or reintubation)	Impairment of respiratory function requiring tracheostomy or reintubation, tracheostomy.
Neurologic (infarct or hemorrhagic CVA, or TIA)	Any new, temporary or permanent, focal or global neurological deficit ascertained by standard neurological examination. Includes transient ischemic attacks and ischemic or hemorrhagic cardiovascular accidents.
Renal	Acute renal dysfunction (abnormal kidney function requiring dialysis in patients who did not require this procedure before implant or a rise in serum creatinine >3 times normal baseline or >5mg/dL) and chronic renal dysfunction (an increase in serum creatinine of ≥2mg/dL above baseline or requirement of hemodialysis for ≥90 days).
Hepatic	An increase in any two of the following lab values (total bilirubin, AST, or ALT) to a level >3 times the upper limit of normal 14 days post-implant (or if hepatic dysfunction is the primary cause of death).
GI	Cholecystitis, Crohn’s disease, diverticulitis, esophagitis, GERD, hiatal hernia, ischemic bowel requiring surgical exploration, pancreatitis with abnormal amylase/lipase requiring nasogastric suction therapy, polyps, or ulcer.
OTHER
Bleeding (coagulopathy, mediastinum or pocket, thorax, gastrointestinal)	An episode of coagulopathy, or bleeding of the mediastinum, pocket, thorax, or gastrointestinal system that results in death or the need for re-operation, hospitalization, or transfusions of red blood cells (≥4U PRBC within any 24 hr period in the first 7 days post-implant or ≥2U PRBC within any 24 hr period after 7 days post-implant).
Infection (driveline, blood stream, pulmonary, mediastinum or pocket)	An infection accompanied by pain, fever, drainage and/or leukocytosis that is treated by anti-microbial agents (non-prophylactic). Driveline infection: Positive culture from the skin and/or tissue surrounding the drive line or from the tissue surrounding the external pump housing, with the need for treatment, when there is clinical evidence of infection (pain, fever, drainage, leukocytosis). Blood stream infection: Evidence of systemic involvement by infection manifested by positive blood cultures and/or hypotension. Pulmonary infection: Positive culture from bronchial lavage with findings on a CT scan or x-ray of lung consolidation. Mediastinum or pocket: Positive culture from skin/tissue surrounding the external housing of an implanted pump or the mediastinum, requiring treatment, when there is clinical evidence of infection (pain, fever, drainage, leukocytosis).
Reoperation (bleeding, infection, wound dehiscence, wound debridement)	Return operation due to bleeding, infection or disruption of the apposed surfaces of a surgical incision requiring surgical repair.
Device Malfunction	Failure of one or more components of the mechanical circulatory device system which either directly causes or could potentially induce a state of inadequate circulatory support or death. This includes pump and non-pump failures.