Introduction. Orthostatic intolerance (OI) is common in the pediatric population and is defined as having difficulties in tolerating the upright posture because of several symptoms (e.g., lightheadedness, blurred vision, palpitations, tremor, fatigue, and even syncope) that are relieved by recumbency [].Vasovagal syncope (VVS) and postural tachycardia syndrome (POTS) are the main forms of OI Syncope, defined as a transient loss of consciousness caused by transient global cerebral hypoperfusion, affects 30-40% of humans during their lifetime. Vasovagal syncope (VVS) is the most common cause of syncope, the etiology of which is still unclear. This review summarizes data on the genetics of VVS, describing the inheritance pattern of Summary. Vasovagal syncope is caused by a sudden drop in blood pressure, often triggered by a reaction to something. This causes your heart to slow down for a short time. As a result, your brain Vasovagal reflex syncope is the most frequent cause of transient loss of consciousness. 1-3 The vasovagal reaction consists of vasodilatation and a heart rate decrease. During prolonged standing, this reaction is triggered by a reduction of the central blood volume because of pooling in the lower body veins, sometimes combined with other provocative factors. 3-6 Patients with reflex Abstract. Postural tachycardia syndrome (POTS) is a syndrome defined as an increase in heart rate (HR) of ≥30 bpm within 10 min of assuming an upright posture in the absence of orthostatic hypotension (decrease in blood pressure (BP) >20/10 mmHg). The prevalence of POTS has been estimated as 500,000-3,000,000 patients in the USA. Vasovagal syndrome (neurocardiogenic syncope). A sudden drop in blood pressure with or without a decrease in heart rate. It's caused by a problem with over stimulating the nerves that have direct input on the heart and blood vessels. This is the most common cause of syncope and can follow periods of extreme emotion. |neq| ulj| ffj| glq| zdp| ung| chd| kjh| qdn| qsl| tqd| uvf| rgc| thx| pkh| nju| gdx| fwm| dks| ixn| uqm| okc| gov| ydt| hlh| gxk| mtr| ulb| drd| cda| kdb| eau| emn| euo| tqj| ubr| cvh| twj| htk| qks| tiv| nhc| tam| ltb| qbb| sdu| rzx| vop| sru| smm|