Assessment of clinical characteristics of cardiac amyloidosis as a potential underlying etiology in patients diagnosed with heart failure with preserved ejection fraction.

Background: Heart failure with preserved ejection fraction (HFpEF) is heterogeneous clinical syndrome. Transthyretin cardiac amyloidosis (CA) is an underdiagnosed cause of HFpEF. Red flags are extremely useful for suspecting CA.

Aims: We aimed to evaluate the frequency of cardiac and extracardiac manifestations of CA in HFpEF patients based on red flags.

Methods: Baseline characteristics of 85 patients were recorded during admission. Electrocardiogram and echocardiography were performed. All patients were examined for red flags. Cardiac scintigraphy was performed in 85 patients.

Results: The mean (standard deviation [SD]) age of the study group was 67.9 (9.8) years, and 52 (61.2%) patients were female. At least 1 red flag was observed in 67% of HFpEF patients. Only 4 of the patients had more than 3 red flags. The mean number of red flags in a patient with HFpEF was 1.3. Extracardiac clinical red flags were observed in only 9 (10.5%) patients. Cardiac clinical red flags were extremely rare. An electrocardiographic red flag was detected in 2 out of 10 patients and an echocardiographic red flag in 4 out of 10 patients with HFpEF. Scintigraphy showed that 17.6% of all patients have had a grade 2 or 3 cardiac uptake. The patients with wild-type transthyretin CA had twice as many red flags as those without.

Conclusion: The results of the study showed that patients diagnosed with HFpEF had an average of 1.3 red flags suggestive of CA. In real life, extracardiac red flags are rare, while electrocardiographic and echocardiographic red flags are more common in patients with HFpEF.