Differences in autonomic nerve function in patients with silent and symptomatic myocardial ischaemia.

Abstract

Patients with silent ischaemia and pain pathways presumed to be intact have an enhanced peripheral vasodilator response, and if this applied to the coronary vasculature it could provide a mechanism for limiting ischaemia to below the pain threshold. Patients with pure silent ischaemia have evidence of sympathetic autonomic dysfunction.

Cardiovascular Autonomic Neuropathy Due to Diabetes Mellitus: Clinical Manifestations, Consequences, and Treatment

“…The mechanisms of painless myocardial ischemia are, however, complex and not fully understood. Altered pain thresholds, subthreshold ischemia not sufficient to induce pain, and dysfunction of the afferent cardiac autonomic nerve fibers have all been suggested as possible mechanisms (18). A recent investigation that used positron emission tomography to measure regional cerebral blood flow as an index of regional neuronal activation has shown that impaired afferent signaling resulting from autonomic dysfunction is associated with failed signal transmission from the thalamus to the frontal cortex (19).…”

Diabetic Cardiovascular Autonomic Neuropathy

“…Altered pain thresholds, subthreshold ischemia not sufficient to induce pain, and dysfunction of the afferent cardiac autonomic nerve fibers have all been suggested as possible mechanisms. 32 Positron emission tomography to measure regional cerebral blood flow as an index of regional neuronal activation has shown that impaired afferent signaling resulting from autonomic dysfunction is associated with failed signal transmission from the thalamus to the frontal cortex. 33 In the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study of 1123 patients with type 2 diabetes, cardiac autonomic dysfunction was a strong predictor of ischemia.…”

Diagnostic and prognostic value of ambulatory ECG (Holter) monitoring in patients with coronary heart disease: a review

“…Evidence of autonomic nerve dysfunction has also been described in non-diabetic patients with SI [27]. While peripheral neuropathy can explain some instances of SI, it should be noted that SI can also be observed in many non-diabetic persons who have no evidence of neuropathy.…”