Electrocardiography (ECG or EKG)


ECG is the recording of the electrical activity of the heart from electrodes placed on the surface of the body.

Cat ECG   It is commonly used in veterinary practice to:

- diagnose and monitor cardiac arrhythmias and conduction disturbances

- evaluate & monitor the effects of cardioactive drugs

- monitor cardiac function before, during and after surgery



Many cardiac arrhythmias are episodic in nature, especially in the cat. This means that some rhythm or conduction abnormalities can be missed during a standard 1-minute ECG recording. However, some modern technologies are available to enhance the diagnostic yield of ECG recording in order to provide sufficient evidence for a correct diagnosis and useful information for prognostication and therapeutic interventions.

Radio-telemetric monitoring

Dog ECGThis technology provides a continuous monitoring of a patient's ECG. The ECG leads are connected to the patient's skin via self-adhesive pre-gelled electrodes and the trace is transmitted via a small radio-transmitter to a remote unit. This system allows free movements of the patient within the radio reception radius and a continuous real-time monitoring. Furthermore, most radio-telemetric equipments can store hours of recording in a solid state memory (usually computer-based) and allow an accurate retrospective analysis of the patient's ECG.  

24h (Holter) ECG recording

ECG AnalysisTwenty-four hour ECG recorders (or simply 'Holters') have been available for many decades. However, in the last few years, Holter units have become cheaper, smaller and significantly lighter, making this technology suitable also in cats. The major advantage of Holter monitoring is that the entire trace can be accurately analysed by dedicated computer programs, with minimal manual input, allowing several measurements such as average heart rate, total number of complexes and their classification into supraventricular, ventricular, premature, etc. Periods of tachycardia and bradycardia and their duration are also detected.

Ambulatory event recorders (ER)

Dog Copllapse SyncopeEvent recorders, also known as cardiac loop ECG recorders or memory loop event recorders, can provide extended monitoring of cardiac rhythm in feline patients These recorders are particularly useful in recording cardiac rhythm during episodes of unexplained syncope or weakness. ER has other potential advantages over Holter monitoring, being usually smaller and lighter than Holter monitors. Moreover, they do not require computer analysis or experienced technicians to obtain a rhythm strips. Finally, the cost of wearing a cardiac event recorder for several days is significantly cheaper than several 24h Holter analyses.  However, even ambulatory event recorders present some pitfalls. For example, lead detachment may represent an important limitation, especially after a few days of monitoring and some cats may become uncooperative and attempt to remove the recorder. Finally, the interval between clinical episodes may be significantly longer than the time the event recorder is worn by the patient (usually less than 1-2 weeks)

Implantable loop recorder (ILR)

Dog Syncope FaintingThe ILR is a small, self-contained monitoring system that can be easily implanted subcutaneously, close to the heart, to provide continuous ECG recording for several months. The device contains a solid state loop memory, which can store the ECG trace recorded before, during and after a symptomatic event. ECG traces can be stored automatically or after manual activation, by using a dedicated remote activator and can subsequently be retrieved and analysed with a programmer placed over the device, in the same fashion as a pacemaker interrogation. Unlike ER, ILR is less affected by technical faults (i.e. lead detachment) and provides a much longer and reliable monitoring. The diagnostic utility of ILRs has also been reported in cats.



Please contact us for further details