Fig. 2From: Microvascular effects of intravenous esmolol in patients with normal cardiac function undergoing postoperative atrial fibrillation: a prospective pilot study in cardiothoracic surgeryDescription of the study protocol. Each step lasted 45 min and the dose of esmolol was gradually increased to control ventricular heart rate (HR) between 60 and 90 beats/min. POAF postoperative atrial fibrillation. VOT vascular occlusion test Back to article page