syncope

Heart diseases that cause fainting include: Bradyarrhythmia ( Unknown ) or Tachycardia ( Product ) Syncope can be caused by arrhythmias such as arrhythmia, or by a temporary drop in blood pressure such as neuro-mediated syncope or orthostatic hypotension. Diseases that can cause syncope other than heart disease include: cerebral infarction ( Noise ) These include brain diseases such as epilepsy, spermatozoa, liver failure, and mental illness.

Adams-Stokes syndrome

Adams-Stokes syndrome is a disease that causes fainting due to arrhythmias such as bradyarrhythmia and tachyarrhythmia. In the case of bradyarrhythmia, if there is any drug that causes bradycardia, it will be discontinued, and if the symptoms do not disappear or if there is severe bradycardia, an artificial pacemaker will be implanted.

Because tachyarrhythmia accompanied by syncope is a serious arrhythmia, cardiac electrophysiology tests are performed at a specialized hospital and aggressive treatment is administered by combining appropriate antiarrhythmic drugs, radiofrequency catheter ablation, implantable cardioverter defibrillators, and other methods.

Neurally Mediated Syncope

This refers to a transient drop in blood pressure caused by autonomic reflexes that occur in various situations. There are three types of syncope: one in which blood pressure drop is the main cause, one in which bradycardia occurs in addition to blood pressure drop, and one in which bradycardia is the main cause rather than blood pressure drop. There are three types of neurally mediated syncope: Vasovagus nerve ( The final exam ) syncope, Emotions ( Jodo ) syncope, Carotid sinus hypersensitivity ( Medical supplies and containers ) Syncope, situational syncope ( cough ( cough ) , urination, defecation, exercise, Swallowing ( Engage ) fainting, etc.

For diagnosis, it is helpful to examine in detail the circumstances under which fainting occurred. A tilt test is useful for a definitive diagnosis. This is a test in which the patient lies on a 60-80 degree tilted table and blood pressure and pulse are observed for 30-120 minutes. In the case of neuro-mediated syncope, a drop in blood pressure accompanied by fainting or discomfort is induced.

In most cases, fainting can be prevented by lifestyle advice (correcting irregular sleep and eating habits, not drinking too much alcohol), avoiding situations that cause fainting, etc. However, some patients experience repeated fainting attacks and require medication or a special artificial pacemaker.

Orthostatic hypotension

This is a disease that causes a drop in blood pressure when standing up. If the drop in blood pressure is mild, dizziness and lightheadedness will appear, and if the drop is severe, fainting will occur. It may also be caused by high blood pressure medication or medication that dilates blood vessels.

If the drop in blood pressure is severe or lasts for a long time, or if it worsens progressively, there may be an underlying nervous system disorder.

Source: Houken “Sixth Edition Family Medicine Encyclopedia” Information about the Sixth Edition Family Medicine Encyclopedia

　失神を来す心臓の病気には、徐脈性不整脈(じょみゃくせいふせいみゃく)や頻脈性(ひんみゃくせい)不整脈などの不整脈が原因のものと、神経調節性失神や起立性低血圧などの一過性の血圧低下が原因のものとがあります。心臓の病気以外で失神を来す病気には、脳梗塞(のうこうそく)やてんかんなどの脳の病気、精尿病、肝不全、精神病などがあります。

アダムス・ストークス症候群

　徐脈性不整脈や頻脈性不整脈などの不整脈が原因で失神を起こす病気をアダムス・ストークス症候群といいます。徐脈性不整脈の場合、徐脈の原因になる薬剤があれば中止し、それでも症状がなくならない場合や高度の徐脈がある場合には、人工ペースメーカー植込術を行います。

　失神を伴う頻脈性不整脈は重症の不整脈なので、専門の病院で心臓電気生理学検査を行い、適切な抗不整脈薬、高周波カテーテル・アブレーション、植込型除細動器などの方法を組み合わせて積極的な治療を行います。

神経調節性失神

　いろいろな場面で生じる自律神経時反射により引き起こされる一過性の血圧低下をいいます。血圧低下が主体のタイプと、血圧低下に加えて徐脈も生じるタイプ、さらには血圧低下よりもむしろ徐脈が主体のタイプとがあります。神経調節性失神には、血管迷走神経(けっかんめいそうしんけい)失神、情動(じょうどう)失神、頸動脈洞過敏(けいどうみゃくどうかびん)失神、状況失神（咳(せき)、排尿、排便、運動、嚥下(えんげ)失神など）が含まれます。

　診断には、失神が生じた時の状況を詳細に調べることが参考になります。確定診断には傾斜試験が有用です。これは60～80度の傾斜台に寝て、30～120分間、血圧と脈拍を観察する検査です。神経調節失神の場合、失神あるいは気分の不快を伴う血圧低下が誘発されます。

　ほとんどの場合、生活指導（不規則な睡眠・食生活の是正、アルコールの飲みすぎの禁止）失神を引き起こす状況を避ける、などの注意で予防できます。しかし、なかには失神発作を繰り返し、薬物の内服や特殊な人工ペースメーカーが必要になる患者さんもいます。

起立性低血圧

　立位時に血圧低下を来す病気です。血圧の低下の程度が軽い場合はめまい、立ちくらみ症状が現れ、低下が高度であれば失神を来します。高血圧の薬や血管を広げる薬が原因になる場合もあります。

　血圧低下の程度が高度であったり持続時間が長い場合、また進行性にひどくなる場合などは、神経系の病気が基礎にあることがあります。

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