From the Guidelines
Amyloid Transthyretin (ATTR) Cardiomyopathy is characterized by restrictive cardiomyopathy, which is often associated with diastolic dysfunction, as evidenced by the accumulation of amyloid fibrils in the interstitial space between cardiac myocytes, impairing compliance 1.
Relationship between ATTR Cardiomyopathy and Diastolic Dysfunction
The relationship between ATTR Cardiomyopathy and diastolic dysfunction is rooted in the pathophysiology of the disease. As amyloid fibrils accumulate in the heart muscle, they lead to cellular injury and impaired compliance, resulting in restrictive cardiomyopathy, which is characterized by diastolic dysfunction. This is supported by the 2023 ACC Expert Consensus Decision Pathway on Cardiac Amyloidosis, which highlights the importance of early diagnosis and treatment of cardiac amyloidosis to prevent irreversible loss of physical function and quality of life 1.
Key Features of ATTR Cardiomyopathy
Some key features of ATTR Cardiomyopathy include:
- Accumulation of amyloid fibrils in the interstitial space between cardiac myocytes
- Impaired compliance and restrictive cardiomyopathy
- Diastolic dysfunction
- Increased morbidity and mortality
- Often under-recognized in patients with heart failure
Diagnosis and Treatment
Diagnosis of ATTR-CM is often missed or mistaken as hypertrophic cardiomyopathy or HFpEF of unknown cause. However, with the use of imaging techniques and monoclonal light chain testing, accurate noninvasive diagnosis of ATTR-CM is possible without the need for confirmatory endomyocardial biopsies 1. Treatment options for ATTR-CM include disease-modifying therapies such as TTR silencers, TTR stabilizers, and TTR disruptors. Tafamidis, a TTR stabilizer, is generally preferred over diflunisal due to its better safety profile and proven efficacy in clinical trials 1.
Management of ATTR-CM
Management of ATTR-CM involves a comprehensive approach, including:
- Evaluation and management of autonomic dysfunction, volume status, and arrhythmia
- Use of disease-modifying therapies such as tafamidis
- Regular monitoring of renal function, blood pressure, and signs of fluid retention
- Consideration of the benefits and risks of ICDs and CRT in patients with ATTR-CM and EF ≤40% 1
From the Research
Relationship between Amyloid Transthyretin (ATTR) Cardiomyopathy and Diastolic Dysfunction
- The studies provided do not directly address the relationship between Amyloid Transthyretin (ATTR) Cardiomyopathy and diastolic dysfunction 2, 3, 4, 5, 6.
- However, it is mentioned that Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, life-threatening disease characterized by the aggregation and deposition of amyloidogenic misfolded transthyretin (TTR) in the myocardium, which can result in restrictive cardiomyopathy and heart failure 2.
- Restrictive cardiomyopathy is often associated with diastolic dysfunction, which is a condition where the heart has difficulty relaxing and filling with blood during diastole 6.
- While the studies do not explicitly discuss the relationship between ATTR-CM and diastolic dysfunction, they do highlight the importance of treating ATTR-CM to reduce symptoms, hospitalization, and mortality 2, 3, 4, 5, 6.
- Tafamidis, a TTR stabilizer, has been approved for the treatment of adults with ATTR-CM and has been shown to reduce all-cause mortality and frequency of cardiovascular-related hospitalizations relative to placebo in patients with ATTR-CM 2, 4, 6.
Treatment Options for ATTR-CM
- Tafamidis is a safe and effective drug in reducing symptoms, hospitalization, and mortality in accurately selected patients affected by hereditary and wild-type transthyretin amyloid cardiomyopathy 4.
- Other treatment options, such as patisiran, are also being investigated for the treatment of ATTR-CM, particularly in patients with polyneuropathy 3, 6.
- The choice of treatment depends on the individual patient's needs and the severity of their condition, and should be made in consultation with a multidisciplinary team of healthcare professionals 6.