植込み型心臓ペースメーカおよび植込み型除細動器に対する診断領域Ⅹ線の影響とその対策

摘要

The effects of diagnostic X-rays on implantable cardiac pacemakers and implantable cardioverter defibrillators (ICDs) were investigated. A total of 33 pacemakers from six manufacturers and nine ICDs from four manufacturers were irradiated using several X-ray units (plain X-ray diagnostic unit, under-table system fluoroscopy unit, over-table system fluoroscopy unit, biplane cardiac digital angiography unit, DSA unit and cone-beam CT unit). No systematic reset phenomena were observed in any pacemakers and ICDs under the X-ray irradiation. Nevertheless, over-sensing associated with the lack of a few pulses was observed in three of 33 pacemakers under radiation exposure. It has been proven that diagnostic X-rays might affect pacemaker function. Since the duration of the over-sensing under the radiation was very short and included transient episodes, this sensing failure, therefore, induced by radiation exposure would not affect the health of pacemaker recipients. ICDs were not affected by radiation exposure at a clinical dose. It is recommended that caution be exercised in direct irradiation to the pacemaker. Using a copper sheet of 2.0 mm thickness or more prevented over-sensing of pacemakers in the present study, especially when serial X-ray exposures were used with an over-table fluoroscopy system or cone-beam CT unit.%近年，国内における植込み型心臓ペースメーカ（以下ペースメーカ）および植込み型除細動器（implantable cardioverter defibrillator：以下ICD）の患者数は，30～40ガ人と推測され，年々増加け頃向にある．これらのペースメーカやICDは，電磁波，特に変動磁界による干渉が指摘されており，magnetic resonance imaging （MRI）検査はペースメーカあるいはICD装着患者にとって禁忌とされている．