Fernex et al. Journal of Medical Case Reports 2012, 6:241 http://www.jmedicalcasereports.com/content/6/1/241 and his blood pressure under treatment with nifedipine (2×30mg/day) was 120/85mmHg. During the eight months after his surgery, our pa- tient presented the following new symptoms, which worsened very progressively until they impaired his normal daily functioning: shortness of breath on exer- tion, light-headedness and dizziness on standing, fa- tigue, excessive daytime sleepiness and hypersomnia (up to 16 hours a day). Sleep was not restorative and our patient described daytime somnolence. He could no longer attend his work. He also complained of ab- dominal cramps after meals and constipation. An echocardiogram and thoracic computed tomog- raphy showed no relevant findings. Our patient devel- oped depressive symptoms, which showed partial improvement after the introduction of venlafaxine (150mg/day). Other medications included amlodipine (5mg/day) and valsartan (80mg/day) for residual hyper- tension, and aspirin (100mg/day). Eighteen months after his aortic surgery, our patient was finally admitted to our hospital because the same symptoms persisted and had worsened. A complete his- tory revealed that he was not known for snoring, but his girlfriend reported leg jerks during sleep and sleep talk- ing. He denied chronic nasal congestion or substance abuse. He drank two litres of cola-drink per day. On physical examination, our patient could not stand for more than 10 minutes because of dizziness and a sense of weakness. His body mass index was 21kg/m2 and a small oral cavity with micrognathia was observed. He scored 19 out of 24 on the Epworth Sleepiness Scale, 6.6 out of 7 on the Fatigue Severity Scale and 14 out of 63 on the Beck Depression Inventory. Laboratory values were in the normal range, including thyroid-stimulating hormone and arterial blood gases. Adrenal insufficiency was excluded. Pulmonary function tests and cerebral magnetic resonance imaging were not contributory. A polysomnography and a multiple sleep latency test detected breathing abnormalities, as detailed in Table 1. There were no periodic leg movements (index of peri- odic limb movements in sleep: 7) and narcolepsy was ruled out by the multiple sleep latency test (mean la- tency: 11min 33s). Thus, it was concluded that our pa- tient had UARS together with micrognathia and Table 1 Polysomnography Central apnea (N) Obstructive hypopnea (N) Respiratory effort-related arousals (N) Apnea-hypopnea index Respiratory disturbance index Mean heart rate (beats/min) Page 2 of 5 excessive daytime sleepiness [3]. The UARS was severe enough to explain part of his symptoms, such as his ex- treme fatigue and functional impairment, but could not explain the orthostatic symptoms [4]. An orthostatic measurement of his heart rate and blood pressure showed an important heart rate incre- ment on standing (from 77 beats/min supine to 106 beats/min when getting up and 146 beats/min after 5min of standing). During the test, his blood pressure remained stable at a value of 115/83mmHg and our pa- tient developed his usual symptoms of dizziness, short- ness of breath, paresthesia and general weakness. After seven minutes, he could no longer tolerate the standing position. A head-up tilt test reproduced the same ortho- static symptoms, with an increased sinus rate and stable blood pressure (Table 2). The increase in heart rate without orthostatic hypotension along with the accom- panying symptoms confirmed the presence of POTS. A 24 hour Holter monitoring excluded any significant arrhythmia. Amlodipine and valsartan were stopped and propran- olol was introduced (3×10mg/day), with some improve- ment of the orthostatic symptoms. Our patient entered an exercise rehabilitation program. He was encouraged to maintain a high liquid and salt intake. Two months later, our patient was able to perform 70% of his normal activities of daily living under this treatment. He described nearly complete disappearance of hypersomnia, excessive daytime sleepiness and fa- tigue. Despite this initial improvement, our patient experienced a recurrence of the same symptoms after the following six months, albeit of reduced severity. Discussion POTS typically affects patients aged 15 to 50 years [5]. The typical symptoms are posture-related and are relieved by lying down or sitting. They include light- headedness, weakness, dizziness, breathing difficulties, tremulousness, blurred vision, palpitations, anxiety and, occasionally, syncope. Our patient presented many of these symptoms. Exacerbation by exertion is also a com- mon clinical feature. Non-orthostatic symptoms include fatigue, migraine and gastrointestinal tract symptoms (nausea, bloating, diarrhea, constipation, abdominal 1 104 131 12.3 27.7 70 Mean oxygen saturation (%) Minimum oxygen saturation (%) Morning pH Morning partial pressure of CO2 (kPa) Morning partial pressure of O2 (kPa) Morning HCO3- (kPa) 95 90 7.4 6.5 11 30