Paradoxical sinus deceleration during dobutamine stress echocardiography: Diagnostic significance and therapeutic approach

Introduction. Paradoxical sinus deceleration is an uncommon hemodynamic response observed during dobutamine stress echocardiography, characterized by a decrease in heart rate despite escalating doses of dobutamine, with or without a concomitant reduction in arterial blood pressure. Earlier studies associated this phenomenon with inferior myocardial ischemia, whereas more recent evidence suggests a potential autonomic mechanism mediated by activation of the Bezold-Jarisch reflex, particularly in the absence of left ventricular segmental wall motion abnormalities. The reported incidence of paradoxical sinus deceleration ranges from 5% to 10%, and its clinical significance appears to depend primarily on the presence of inducible ischemia. Case Report. A 53-year-old woman with arterial hypertension, dyslipidemia, and a positive family history of cardiovascular disease was evaluated for atypical anginal symptoms. At the maximal dose of dobutamine, asymptomatic paradoxical sinus deceleration accompanied by transient hypotension was observed. Electrocardiography revealed no ischemic changes or rhythm disturbances, and echocardiography demonstrated no left ventricular segmental wall motion abnormalities. The examination was therefore interpreted as negative for inducible myocardial ischemia. Conclusion. In the absence of echocardiographic evidence of ischemia, paradoxical sinus deceleration during dobutamine stress echocardiography does not represent an independent indication for invasive diagnostic procedures. The absence of left ventricular segmental wall motion abnormalities is pivotal in therapeutic decisionmaking, and conservative medical management with structured clinical follow-up constitutes a rational and safe approach.