antesystole

an·te·sys·to·le

(an'te-sis'tō-lē),
Premature activation of the ventricle responsible for the preexcitation syndrome of the Wolff-Parkinson-White or Lown-Ganong-Levine types.

an·te·sys·to·le

(an'tĕ-sis'tō-lē)
Premature activation of the ventricle, responsible for the preexcitation syndrome of the Wolff-Parkinson-White or Lown-Ganong-Levine type.