Differential:

• Oesophagitis
• Pulmonary embolism
• Tachyarrhythmia
• Precordial catch syndrome
• Costochondritis (Tietze syndrome)
• Catecholamine secreting tumours?
• Cardiomyopathy? Ischaemic cardiomyopathy eg anomalous origin of left coronary artery (from pulmonary artery) – but kids, either too young to describe pain (infants) or else too mild to present with angina (instead present with failure).  Arrhythmogenic ventricular cardiomyopathy (usually right, but biventricular involvement recognised) can present with pain but usually syncopal episodes.  [Circulation. 2019;140:e9–e68]
• Fabry’s as cause of bizarre pain (heart involvement but pain usually GI).