Cardiac amyloidosis is a condition where abnormal protein deposits build up in the heart, making it stiff and causing it to work less effectively. One common type is caused by a normal blood protein called transthyretin (TTR), which can become unstable and form these deposits. When this happens, it is called ATTR-CM, a form of heart disease caused by TTR protein buildup. This can lead to symptoms like tiredness, shortness of breath, or swelling.

Bilateral carpal tunnel syndrome (CTS) is recognized as an early clinical sign of systemic amyloidosis, especially in the context of TTR amyloidosis, where amyloid deposits accumulate in the median nerve. Early identification of cardiac amyloidosis, particularly in patients with bilateral CTS, may allow for earlier intervention with disease-modifying therapies, such as tafamidis, which has been shown to improve survival and reduce hospitalizations in patients with cardiac amyloidosis.

The purpose of this study is to identify patients to evaluate them for previously undiagnosed cardiac amyloidosis. The collected information will help estimate the prevalence of cardiac amyloidosis among participants with prior bilateral CTS using a PYP nuclear scan (technetium-99m pyrophosphate scan). A PYP scan is a special heart imaging test that helps doctors see if certain abnormal proteins are building up in the heart. It's mainly used to help diagnose cardiac amyloidosis.

Inclusion Criteria:

• Patients aged 55 and older at the time of surgery.
• Patients who have had bilateral carpal tunnel release surgery (i.e., at least two carpal tunnel release surgeries, one for each hand).
• Patients who underwent surgery between the years 2010-2015.

Exclusion Criteria:

• Patients under the age of 55 at time of surgery.
• Patients who had unilateral carpal tunnel release surgery or surgery on only one hand.
• Patients known alternative neurologic diagnosis explaining CTS
• Patients with incomplete medical records
• Patient denies PYP scan
• Previously diagnosed amyloidosis through previous positive PYP, medical notes or self-reported
• Patients with prior negative amyloid work up
• Cognitive/communication issues without available translation support