Current evidence indicates a modulating role of respiratory processes in cardiac interoception, yet whether altered breathing patterns can influence heartbeat-evoked potentials (HEP) remains inconclusive. Here, we examined the effects of voluntary hyperventilation (VH) on scalp-recorded HEPs in epilepsy patients (N = 80). Using cluster-based permutation analyses, HEP amplitudes were compared across pre-VH and post-VH conditions within young and elderly subgroups, as well as for the total sample. No HEP differences were detected for younger participants or across the full sample, but results showed an increased HEP amplitude at 530 – 560 ms after R-peak within the senior subgroup during pre-VH compared to post-VH, denoting decreased cardiac interoceptive processing as a function of breathing frequency in elderly individuals. The present study, thus, provides initial evidence of ventilatory-related HEP modulations in elderly epilepsy patients, emphasizing HEP’s utility as an interoceptive neural marker that could partially extend to the representation of pulmonary signaling. We speculate that aberrant CO2-chemosensing, coupled with disturbances in autonomic regulation, might constitute the underlying pathophysiological mechanism behind the obtained effect. Available databases involving patient records of routine VH assessment may constitute a valuable asset in disentangling the interplay of cardiac and ventilatory interoceptive information, providing thorough clinical data to parse, as well as increased statistical power and estimates of effects with higher precision through large-scale studies.