A multi-center, prospective & retrospective, observational single-arm study of the clinical outcomes up to one year collected from electronic health records of patients which have undergone standard of care implantation of Impella 5.5, regardless of clinical situation or indication. All patients will be enrolled via an IRB-approved Waiver of Informed Consent and HIPAA Authorization.

All patients who were supported retrospectively (prior to site IRB approval) with Impella 5.5 at the investigative site will be entered into the SURPASS registry and specified as the retrospective cohort.

Inclusion Criteria:

• Age ≥ 18 years
• Subject has previously undergone an Impella 5.5 implant at a study site

Exclusion Criteria:

• Patients not receiving Impella 5.5

Patients 18 years old and older who previously received an Impella 5.5 implant at the study site