Читать книгу Manual of Equine Anesthesia and Analgesia - Группа авторов - Страница 158

 Large, abnormal morphology QRS complexes that appear before a normal beat was expected. Therefore, the R–R interval is shorter.

 The depolarization from the PVC travels retrograde and blocks the next impulse from the SA node, which can result in a compensatory pause after the abnormal beat.Note: Singular to several PVCs are often identified in normal horses.

 The PVC is not conducted via the normal conduction pathway; hence, its morphology is different and it is of longer duration than a normal QRS complex.

 The PVC is not associated with the preceding P wave.

 Runs of PVCs are of concern and may result in weakness, syncope, ventricular tachycardia and death.

 PVCs do not allow for complete and normal filling of the ventricle, which affects the SV and results in a lower cardiac output and/or hypotension.