The Bezold-Jarisch reflex in acute inferior myocardial infarction: clinical and sympathovagal spectral correlates.

BACKGROUND

The cardiodepressor Bezold-Jarisch reflex (BJR) in acute inferior myocardial infarction (AMI) is traditionally considered as an indicator of successful thrombolysis.

HYPOTHESIS

The study aim was to elucidate the role of the autonomic nervous system in the pathogenesis of a BJR response in patients with AMI by tracing spectral profiles of heart rate variability (HRV).

METHODS

We studied 32 patients who presented with BJR after starting intravenous thrombolysis for an inferior AMI. Spectral components of HRV were analyzed over the three specific 5-min periods preceding and following reflex activation. Clinically, the occurrence of BJR was correlated with the outcome of thrombolysis to achieve timely reperfusion and sustained coronary artery patency.

RESULTS

The BJR was associated with early reperfusion in 94% of the patients, and with benign transient bradyarrhythmias and patent Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow right coronary arteries in 89% of the patients. Spectral analysis revealed a characteristic pattern of a sympathetic predominance with an impending gradual vagal withdrawal up to the onset of BJR, as reflected by progressive increases in low-frequency and reciprocal changes in high-frequency powers.

CONCLUSIONS

The BJR in inferior AMI represents a reliable prognosticator of timely reperfusion and sustained coronary patency. Stimulation of vagal afferents in response to sympathetic overactivity may be the underlying pathogenetic mechanism promoting a BJR response.