Case Presentation: A 77-year-old male with a history of paroxysmal atrial fibrillation s/p two ablations, hypertension, hyperlipidemia, type 2 diabetes mellitus, heart failure with preserved ejection fraction (HFpEF), and obstructive sleep apnea presented with chronic exertional dyspnea persisting for approximately one year.During this period, he was seen in the cardiology clinic and hospitalized for atrial fibrillation with rapid ventricular response, and HFpEF exacerbations. Echocardiography revealed an ejection fraction of 50–55% with grade III diastolic dysfunction. Left heart catheterization demonstrated non-obstructive coronary disease. Despite guideline-directed medical therapy, including torsemide, empagliflozin, and spironolactone, his symptoms remained refractory and was therefore referred to a tertiary center for further evaluation.Exercise right heart catheterization at the tertiary center showed:· PCWP: 20–35 mmHg· RA pressure: 10 mmHg· Mean PA pressure: 28 mmHg at rest· Cardiac index: 1.7A technetium-99m pyrophosphate (PYP) scan demonstrated significant myocardial radiotracer uptake in both ventricles, strongly suggestive of ATTR amyloidosis. The patient was initiated on tafamidis, with subsequent significant improvement in symptoms.
Discussion: Cardiac amyloidosis is increasingly recognized but remains underdiagnosed; its prevalence varies widely by population and clinical setting, with ATTR cardiac amyloidosis found in up to 10–20% of older adults with heart failure and preserved ejection fraction (HFpEF). Clinical suspicion should be raised in patients with unexplained LV thickening, diastolic dysfunction, arrhythmias, or heart failure symptoms disproportionate to coronary or valvular disease. Diagnosis relies on multimodal imaging, including echocardiography, cardiac MRI, and nuclear scintigraphy (e.g., PYP scan), with biopsy reserved for uncertain cases. Disease-modifying therapy such as tafamidis has transformed management, improving survival and quality of life.
Conclusions: This case highlights the importance of maintaining a high index of suspicion for cardiac amyloidosis in patients with unexplained dyspnea and HFpEF. Early recognition and initiation of disease-specific therapy can significantly improve outcomes.