Ventricular flutter is an arrhythmia, more specifically a tachycardia affecting the ventricles with a rate over 250-350 beats/min, and one of the most indiscernible. It is characterized on the ECG by a sinusoidal waveform without clear definition of the QRS and T waves. It has been considered as a possible transition stage between ventricular tachycardia and fibrillation, and is a critically unstable arrhythmia that can result in sudden cardiac death.It can occur in infancy, youth, or as an adult. It can be induced by programmed electrical stimulation. References
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http://www.medscape.com/viewarticle/409172_3
Consequently, assessment of nightmare disorders using polysomnography has to last for a longer period, in order to let the patient getting used to the artificial environment.Self-report by a questionnaire or by a diary is another way to investigate nightmare disorders. However, these methods are questionable. Indeed, when filling out questionnaires with questions about a long period, people often tend to underestimate the frequency of their nightmares because of forgetting. On the contrary, filling out a diary every day may lead to an overestimation of the numbers of nightmares, because of the focusing on this phenomenon. Comorbidity
Studies have reported that nightmare disorders were present in 50- 70% of the cases for PTSD, in 17.5% for depression, in 18.3% for insomnia, in 16.7% for schizophrenia and in 49% for borderline personality disorder. For all psychiatric disorders taken together, nightmare disorders are present in 29.9% of the cases, a much bigger rate than for the general population, which is 2-5%. Nightmare disorders can also be associated with sleep disorders such as night terrors, chronic insomnia and sleep-disordered breathing. The presence of nightmares before a trauma would influence severity of PTSD symptoms. Furthermore, having nightmares is linked to a significantly higher risk of attempting suicide and of death by suicide. Treatment
Stress reduction techniques such as yoga, meditation and exercise may help to eliminate stress and create a more peaceful sleeping atmosphere.Diagnosis and medication can only be given to patients that report the recurring nightmares to a psychiatrist or other physician.