Abstract
BACKGROUND: Dobutamine stress echocardiography is an established diagnostic modality for assessing myocardial ischaemia in patients with known or suspected coronary artery disease. Dobutamine infusion causes dose-dependent increase in heart rate and contractility. However, in some cases, it induces paradoxical sinus deceleration, whose underlying mechanism and clinical significance are not fully understood. CASE SUMMARY: We present episodes of paradoxical sinus deceleration observed during dobutamine stress echocardiography in six (four males and two females) patients and described its patterns of occurrence and clinical and echocardiographic characteristics. DISCUSSION: Paradoxical sinus deceleration occurred mostly at maximal dobutamine infusion was accompanied with a decline in blood pressure and resolved spontaneously following cessation of dobutamine infusion. Individuals experiencing paradoxical sinus deceleration had in common abnormal left ventricle geometry but differed with regard to age, sex, and cardiometabolic risk factors.