Implantation of a dual‐chamber, rate‐adaptive pacemaker in a horse with suspected sick sinus syndrome

Abstract

A five-year-old gelding suffered syncope at the end of a period of exercise. A 24-hour electrocardiogram recording revealed intermittent pauses in the sinus rhythm of up to 10 seconds, indicating sinus node disease; the pauses occurred repeatedly, particularly after exercise. A dual-chamber, rate-adaptive pacemaker was successfully implanted, which prevented excessive postexercise bradycardia and syncope, and allowed the horse to return to work.

Atrial standstill in a donkey with digitoxin intoxication

“…Patients with bradycardia due to atrial standstill can benefit from sympathomimetic agents or vagolytic agents, although sympathomimetics may enhance tissue excitability and promote reentry phenomena (McGuirk and Muir 1985, Bonagura et al 2010, Davey 1986. For this reason, implantation of a pacemaker is usually preferable (van Loon et al 2002, Pibarot et al 1993, Reef et al 1986). In the current case, emergency pericardiocentesis might have been tried, however, it is highly unlikely that either this or implantation of a pacemaker would have changed the prognosis of the severely ill patient.…”

Successful application of closed loop stimulation pacemakers with remote monitoring in 3 miniature donkeys with syncope

“…This pathology is often irreversible and has been treated successfully by pacemaker implantation in horses and donkeys. 3 , 4 , 5 , 6 , 7 The pacemaker monitors heart rate and rhythm and induces a cardiac depolarization by delivering an electrical current via an electrode to the myocardium. 1 Single‐chamber and dual‐chamber pacemakers are available with a variety of programmable pacing modalities.…”

“… 1 Single‐chamber and dual‐chamber pacemakers are available with a variety of programmable pacing modalities. 7 Pacemaker types are described using a letter code where the first and second letters indicate the chamber being paced and sensed, respectively. The third letter indicates the reaction of the pacemaker when an intrinsic beat is sensed.…”

“…3 In veterinary medicine, rate‐adaptive pacemakers based on motion sensors have been described. 7 , 8 , 9 In human medicine, recent pacemakers allow heart rate adaptations during emotional and physical stress by the use of CLS whereby local impedance of the myocardium is monitored, and changes with an altered inotropic state of the myocardium. 10 , 11 , 12 In addition, innovative pacemakers allow remote monitoring of pacemaker function and detection of arrhythmias, resulting in better patient follow‐up.…”

Echocardiographic identification of atrial‐related structures and vessels in horses validated by computed tomography of casted hearts

“…More and more centres offer transvenous electrical cardioversion which requires accurate positioning of catheters in right atrium (RA) and left pulmonary artery (lPA) [9][10][11][12][13][14]. Pacemaker lead implantation, cardiac biopsy procedures and occluder implantation are performed with ultrasound guidance [15][16][17][18]. Equine electrophysiological studies are performed both for research and for diagnostic purposes [19][20][21].…”