Patients with cardiac amyloidosis (CA) — which includes amyloid transthyretin cardiomyopathy (ATTR-CM) — faced diagnostic and treatment challenges when coronary artery disease (CAD) coexists, according to results from a study published recently in Current Problems in Cardiology. CA is a condition caused by amyloid protein buildup in the heart.
While 25% of patients with CA had CAD, this did not significantly worsen outcomes such as mortality or hospitalizations for heart failure.
What is ATTR-CM?
Transthyretin amyloidosis cardiomyopathy (ATTR-CM) is a rare progressive disease of the heart muscle that leads to congestive heart failure. It occurs when the transthyretin protein produced by the liver is unstable. Symptoms include fatigue; shortness of breath; irregular heart rate or palpitations; swelling of the legs, ankles and stomach; brain fog; wheezing; and dizziness. It often goes underdiagnosed because of a lack of awareness and knowledge of the disease. There is currently no cure for ATTR-CM.
But the results highlighted the need for larger studies to better characterize this complex relationship and refine care strategies. Early diagnosis and targeted management of both conditions remains essential to improving patient outcomes.
Read more about ATTR-CM signs and symptoms
CA is an infiltrative cardiomyopathy in which misfolded amyloid proteins accumulate in heart tissue, disrupting function. Among the two main types of CA, ATTR-CM is more common and predominantly affects older adults.
Diagnosis has improved with advanced imaging techniques such as 99mtechnetium bone scintigraphy and magnetic resonance imaging. These tools have made it possible to identify CA noninvasively, facilitating earlier intervention. But CAD’s overlapping symptoms, such as chest pain and heart failure, can delay accurate diagnosis, complicating treatment.
“Larger studies are needed to identify characteristics that will result in a prompt diagnosis of CA in patients with concomitant CAD,” study authors said. They added: “Although our study did not appreciate a significant difference between these two groups, outcomes of our study were likely impacted by a small sample size in the CA with CAD cohort.”
A retrospective analysis of 114 confirmed cases of CA between 2018 and 2021 revealed that 28 patients also had CAD. Those with CAD were predominantly older (with an average age 74.7 vs. 69.7 years), were male (92.9% vs. 60%) and had higher rates of hypertension (92.9% vs. 70%) and dyslipidemia (89.3% vs. 59%) compared to patients with CA alone. Despite these differences, overall rates of mortality and hospitalization remained similar between groups, possibly due to the study’s small sample size in the CA-CAD cohort.
CA with coexisting CAD may exacerbate symptoms and complicate management strategies. Research shows that patients with CAD and CA experienced longer hospital stays, higher costs and increased in-hospital mortality. Addressing these challenges would require accurate diagnosis and tailored therapeutic approaches. For example, novel treatments for ATTR, such as tafamidis and TTR silencers such as patisiran, have shown promise in stabilizing disease progression and improving symptoms.
The results underscored the importance of early recognition and comprehensive care for patients with both CA and CAD. Physicians must remain vigilant in identifying CA and ATTR-CM in patients presenting with acute coronary symptoms to optimize treatment and avoid unnecessary interventions. Collaborative care models integrating cardiologists and amyloidosis specialists may improve outcomes.
Ultimately, larger studies are needed to clarify the interplay between these conditions. As diagnostic methods and therapies continue to advance, patients with CA and CAD can anticipate better care and improved quality of life.
