The baroreceptor reflex is apowerful negative feedback control mechanism thatbuffers acute changes in cardiovascular function andregulates the fluctuations in blood pressure. Few casesof labile blood pressure after the resection of a secondCBT in familial disease have been reported in theliterature. We report the cases of two family membersaffected with bilateral CBT and discuss the indicationfor surgery in the presence of bilateral familial CBT. Inone case a bilateral CBTexcision was performed whilethe other, because of the occurrence in the first familymember of a life-threatening loss of the arterialbaroreceptor function, was left untreated.Case 1A 47-year old female patient was admitted because ofa small painless mass in the left cervical region. Shehad had surgery for a papillary carcinoma of thethyroid gland 2 years previously. A colour Dopplerwas performed and showed the presence of a solid,hypoechoic mass 2.4 cm in diameter at the level of theleft carotid bifurcation. Angiography showed thepresence of a bilateral CBT. The left tumour wasremoved from the carotid vessels in a sub-adventitialplane. The postoperative course was uneventful. Thepatient was then re-admitted for removal of the rightcarotid body tumour. The postoperative course wascomplicated by hypertension (240/130 mmHg) andsinus tachycardia (120 beats/min) accompanied bysevere, pounding frontal headaches, nausea, vomiting,and skin flushing. The symptoms were treated withthe intravenous administration of clonidine andnifedipine. The patient’s heart rate remained a fairlyconstant 100–120 beats/min between hypertensivecrises. The patient developed marked emotionallability which was treated with benzodiazepine. Thepresence of an undiagnosed pheocromocytoma wasexcluded with an ultrasound and 24-hour urine testsfor catecholamines. All other investigations werenormal. However, the patient continued to havehypertensive crisis twice a day. The patient underwentbaroreflex sensitivity evaluation by means of transferfunction analysis, which revealed a severe impairmentof the baroreceptor reflex system consistent with theclinical manifestations. She was discharged underbenzodiazepine, clonidine and b-blockers. At 4-yearfollow-up the patient still complains of hypertensivecrises (once to twice a month) and a disrupted lifestyle.Case 2A 38-year-old female patient was admitted because of