Amyloidosis is a rare, generally multisystem disease that can also involve the heart. Infiltration of the myocardium with amyloid proteins is an important and underappreciated cause of heart failure with preserved ejection fraction in the elderly. We present the case of an 84-year-old man with chest tightness, dyspnoea, and ascites. He had a history of dyslipidaemia and ischaemic heart disease. Initial investigations showed severe diastolic dysfunction and elevated pulmonary artery systolic pressure on echocardiogram along with elevated serum natriuretic peptides. Further evaluation by a magnetic resonance imaging scan of the heart and endomyocardial biopsy confirmed the diagnosis of senile systemic amyloidosis. He made good progress after treatment with conventional heart failure drugs and is currently under consideration to start on specific medications to slow down the progression of amyloidosis. This case aims to increase clinicians' awareness of senile amyloidosis as a cause of heart failure in the elderly.