• 1.

    Strickberger SA, Benson DW, Biaggioni I, et al. AHA/ACCF scientific statement on the evaluation of syncope: from the American Heart Association councils on clinical cardiology, cardiovascular nursing, cardiovascular disease in the young, and stroke, and the quality of care and outcomes research interdisciplinary working group; and the American College of Cardiology foundation: in collaboration with the Heart Rhythm Society: endorsed by the American Autonomic Society. Circulation 2006;113:316327.

    • Search Google Scholar
    • Export Citation
  • 2.

    Krahn AD, Klein GJ, Skanes AC, et al. Insertable loop recorder use for detection of intermittent arrhythmias. Pacing Clin Electrophysiol 2004;27:657664.

    • Search Google Scholar
    • Export Citation
  • 3.

    Krahn AD, Klein GJ, Skanes AC, et al. Use of the implantable loop recorder in evaluation of patients with unexplained syncope. J Cardiovasc Electrophysiol 2003;14 (suppl 9):S70S73.

    • Search Google Scholar
    • Export Citation
  • 4.

    Krahn AD, Klein GJ, Yee R. Recurrent syncope: experience with an implantable loop recorder. Cardiol Clin 1997;15:313326.

  • 5.

    McKeon A, Vaughan C, Delanty N. Seizure versus syncope. Lancet Neurol 2006;5:171180.

  • 6.

    Willis R, Mcleod K, Cusack J, et al. Use of an implantable loop recorder to investigate syncope in a cat. J Small Anim Pract 2003;44:181183.

    • Search Google Scholar
    • Export Citation
  • 7.

    Ferasin L. Recurrent syncope associated with paroxysmal supraventricular tachycardia in a Devon Rex cat diagnosed by implantable loop recorder. J Feline Med Surg 2009;11:149152.

    • Search Google Scholar
    • Export Citation
  • 8.

    James R, Summerfield N, Loureiro J, et al. Implantable loop recorders: a viable diagnostic tool in veterinary medicine. J Small Anim Pract 2008;49:564570.

    • Search Google Scholar
    • Export Citation
  • 9.

    Bright JM, Cali JV. Clinical usefulness of cardiac event recording in dogs and cats examined because of syncope, episodic collapse, or intermittent weakness: 60 cases (1997–1999). J Am Vet Med Assoc 2000;216:11101114.

    • Search Google Scholar
    • Export Citation
  • 10.

    Pezawas T, Stix G, Kastner J, et al. Implantable loop recorder in unexplained syncope: classification, mechanism, transient loss of consciousness and role of major depressive disorder in patients with and without structural heart disease. Heart 2008;94:e17.

    • Search Google Scholar
    • Export Citation
  • 11.

    Frangini PA, Cecchin F, Jordao L, et al. How revealing are insertable loop recorders in pediatrics? Pacing Clin Electrophysiol 2008;31:338343.

    • Search Google Scholar
    • Export Citation
  • 12.

    Fine DM, Tobias AH. Cardiovascular device infections in dogs: report of 8 cases and review of the literature. J Vet Intern Med 2007;21:12651271.

    • Search Google Scholar
    • Export Citation

Advertisement

Evaluation of the diagnostic value of an implantable loop recorder in dogs with unexplained syncope

View More View Less
  • 1 Clinica Veterinaria Malpensa, Via Marconi, 27, 21017 Samarate, Varese, Italy.
  • | 2 Anderson Sturgess Veterinary Specialists, Bunstead Barns, Poles Lane, Hursely, Winchester, Hampshire, SO21 2LL, England.
  • | 3 Clinica Veterinaria Malpensa, Via Marconi, 27, 21017 Samarate, Varese, Italy.
  • | 4 Clinica Veterinaria Malpensa, Via Marconi, 27, 21017 Samarate, Varese, Italy.

Abstract

Objective—To evaluate the diagnostic value of an implantable loop recorder (ILR) in dogs with unexplained syncope.

Design—Prospective case series.

Animals—12 dogs with recurrent unexplained syncope.

Procedures—An ILR was surgically inserted in a pocket created in the subcutaneous tissues of the left hemithorax of each dog. The ILRs were programmed for manual and automatic activation, and event analysis and programming were performed at 3-month intervals and after each syncopal episode.

Results—The ILR was manually activated in 7 of 12 dogs at least once within 45 to 218 days (median, 120 days) after implantation. Four dogs had syncopal episodes associated with sinus tachycardia followed by sinus bradycardia and asystolic pauses. Two dogs had ventricular tachycardia, and 1 dog had sinus node dysfunction with prolonged sinus arrest that coincided with loss of consciousness and falling. Four dogs had no additional syncopal episodes after implantation of the ILR. In the remaining dog, the owner was unable to activate the ILR during the only syncopal episode observed for that dog after ILR implantation. In all 12 dogs, analysis of ECG traces after automatic activation of recording revealed normal cardiac rhythms.

Conclusions and Clinical Relevance—Data gained after manual activation of an ILR provided valuable diagnostic and prognostic information in almost all dogs with unexplained syncopal episodes by confirming or disproving an association between syncope and arrhythmias. However, detection of disturbances in cardiac rhythm after automatic activation did not appear to improve the diagnostic value for an ILR implanted in dogs.

Contributor Notes

Dr. Ferasin's present address is Specialist Veterinary Cardiology Consultancy, 20 Old Bath Rd, Newbury, Berkshire, RG14 1QL, England.

Presented in abstract form at the 17th Annual Congress of the European College of Veterinary Internal Medicine-Companion Animals, Budapest, September 2007.

The authors thank Dr. Kit Sturgess for clinical assistance with 1 of the dogs.

Address correspondence to Dr. Santilli (rasantil@tin.it).