The case of a 26-year-old woman with congenital long QT syndrome and recurrent arrhythmic syncope which had been misdiagnosed as a seizure disorder is presented. Useful criteria for discriminating between loss of consciousness due to congenital long QT syndrome and loss of consciousness caused by seizure activity are discussed. The multiple potential causes and clinical implications of a prolonged QT interval, as well as the clinical features and management of congenital long QT syndrome are reviewed.
CASEA 26-year-old woman presented to a general cardiology clinic with a chief complaint of palpitations. The palpitations had begun a few months prior and had been occurring with increased frequency in recent weeks. She characterized the episodes as a rapid heartbeat that alternated between a regular and irregular rhythm. She denied associated symptoms of chest discomfort or shortness of breath, but did experience lightheadedness. The palpitations lasted 30-60 seconds and occurred once or twice a week over the preceding two months. They seemed to occur at any time of day and without regard to physical activity, stress, or anything else she could identify. They had on occasion awakened her from sleep.Her past medical history was notable for dyslexia and a complex-partial seizure disorder. She had a history of five seizures: a first seizure at age 15, a second at age 18, and a third at age 20, at which point carbamazepine treatment was initiated. Computed tomography and magnetic resonance imaging of the head was normal. An electroencephalogram was normal as well. Ten months previously carbamazepine was discontinued because she had been free of seizures for several years. However, about two weeks prior to her cardiology appointment she had a fourth seizure, and treatment with topiramate was initiated. She had a fifth seizure a few days prior to her cardiology appointment.The seizures always occurred when she was in a state between sleeping and wakefulness and were always precipitated by a loud noise, such as a ringing telephone. She experienced a prodrome of anxiety, lightheadedness and tachycardia. She would hyperventilate prior to losing consciousness. These events were witnessed by her mother, a registered nurse, who noted tonic and focal twitching movements of her daughter. Her mother also reported that her daughter was sometimes incontinent of urine and generally unresponsive for a few minutes during these episodes. When her daughter awakened she was immediately alert and did not feel fatigued or confused.Family history was significant for premature coronary disease in her father, who had undergone coronary artery bypass grafting at 45 years of age. There was no family history of sudden death. Her only medication was topiramate 50 milligrams by mouth twice a day. She did not smoke tobacco, use any illicit drugs, or drink alcohol. She was an art student at a nearby university.Her heart rate was 94 beats per minute and her blood pressure was 118/64 mm Hg. She was a very pleasant, slender young woman. The physical ...
Dyspnoea, a much less specific symptom of ischaemia than chest discomfort, is common among obese patients. Patients with dyspnoea often undergo stress testing as part of their evaluation. We sought to examine the yield of stress testing in non-elderly, obese, sedentary patients with dyspnoea on exertion (DOE) as a chief complaint.We reviewed stress echocardiograms carried out on 203 patients in a stress testing laboratory at a major tertiary care centre. Of these, 81 (40%) fell into a group that was at low risk for coronary artery disease (CAD) by clinical criteria. Ischaemia was detected in two patients in the low-risk group (2.5%), and these results were likely false positives. In the higher risk group, 9.0% of functional tests showed ischaemia; after further testing, 2.5% of the higher risk patients were found to have obstructive coronary lesions. Clinical follow-up was performed for a mean of 815 days. New obstructive coronary disease was detected in 1.6% of all patients, and these patients were from the higher risk group. In obese sedentary patients with DOE but otherwise at low risk of coronary disease stress testing is of very low yield. DOE is generally not an anginal equivalent in this patient population.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.