Inclusion Criteria:

• 1. Ambulatory adults age ≥65 years with TTR-cardiac amyloidosis (confirmed by PYP scan or biopsy)
• 2. Taking beta-blocker

Exclusion Criteria:

• 1. Other compelling indication beta-blocker
• 1. Angina symptoms
• 2. Acute coronary syndrome, myocardial infarction or coronary artery bypass surgery in prior 3 years
• 3. Atrial arrhythmia with hospitalization for rapid ventricular response, prior 1 year
• 4. Sinus tachycardia \>100 bpm, atrial arrhythmia with ventricular rate \>90 beats per minute, systolic blood pressure \>160 mmHg
• 2. Clinical instability (N-of-1 trials are appropriate for stable conditions only)
• 1. Decompensated heart failure
• 2. Hospitalized in past 30 days
• 3. Medication changes or procedures in the prior 14 days that could confound observations, per the Principal Investigator's discretion
• 3. Estimated life expectancy \<6 months
• 4. Moderate-severe dementia or psychiatric disorder precluding informed consent
• 5. Language barrier that will preclude informed consent and ability to comprehend study procedures
• 6. Non-compliance or inability to complete study procedures
• 7. Enrollment in a clinical trial not approved for co-enrollment
• 8. Any condition that, in Principal Investigator or treating physician's opinion, makes the patient unsuitable for study participation