A persons heart rate is within normal range during what is called sinus rhythm, which is indicated by P waves on the electrocardiogram (ECG). Normal sinus rhythm originates from the upper portion of the right atrium, specifically from the sinus node. An arrhythmia is any heart rhythm that strays from normal sinus rhythm with normal atrioventricular (AV) conduction.  Normal sinus rhythm is between 60 and 100 beats per minute. Gender differences are exemplified by a normal range for men between 43 and 93 beats per minutes and for women between 52 and 94 beats per minute. Sinus bradycardia and tachycardia may present as physiologic or non-physiologic.

The type of symptoms that may be experienced can either be related to the arrhythmia or due to the hemodynamic consequences of arrhythmia (dyspnoea or dizziness).  Symptoms of cardiac arrhythmias are similar to those of other medical conditions, for example palpitations, dizziness, light-headedness, syncope, chest discomfort, neck discomfort, dyspnoea, weakness and anxiety. Further, cardiac arrhythmias can have secondary consequences and may be due to underlying heart disease. The symptomatic presentation of cardiac arrhythmias can be unusual and include visual changes, increased urinary frequency or abdominal discomfort, resulting in quite a lengthy list of symptoms.  The severity and type of symptoms are key for determining the aetiology of the arrhythmia and often contributes to the urgency and nature of the treatment/therapy given. Any structural heart disease will further determine the urgency of intervention, evaluation and therapy.

Diagnosis is most effectively obtained using documentation with an electrocardiogram or a monitor. There are 4 types of monitoring available:  – Traditional Holter: continuous recording of ECG over 24 to 48 hours – Event recorder: patient activated recorder with some automatic arrhythmia detection software to store asymptomatic episodes  – Mobile continuous outpatient cardiac telemetry: continuous recording and analysis – Implantable loop recorder: episodes stored in device until it can be interrogated by a physician.

To adequately investigate and treat cardiac rhythm disorder, a collection of electrophysiology (EP) techniques are used. These techniques allow physicians to collect detailed information regarding the underlying causes of the arrhythmia, including the location of the site of origin and can therefore provide a definitive treatment where applicable.  Electrophysiology studies have accomplished:  ●Definitive diagnosis of an arrhythmia (supraventricular or ventricular tachyarrhythmias or a bradyarrhythmia) ●Establish the etiology for syncope (bradyarrhythmia or tachyarrhythmia), especially in patients with structural heart disease ●Stratification for risk of sudden cardiac death ●Evaluate the feasibility or outcome of nonpharmacologic therapy (eg, transcatheter radiofrequency ablation, antiarrhythmic surgery, or implantable cardioverter/defibrillator therapy)

Syncope (fainting) with heart disease patients based on medical history, physical examination, electrocardiography and echocardiography, however further tests are needed to be definitive.

Syncope which are immediately following palpitations.  ● Unexplained syncope

Syncope in patients whose occupation is high risk for themselves and others if a cardiac event was to occur.

EP can effectively help to establish a diagnosis for survivors of sudden cardiac death

EP is utilised for patients with complex tachyarrhythmias who are not diagnosable by non-invasive means.

Unstable angina


Acute decompensated congestive heart failure not caused by the arrhythmia

Major bleeding diathesis

Acute lower extremity venous thrombosis if femoral vein cannulation is desired Electrophysiology studies are most beneficial for patients who are suspected of having a tachyarrhythmia whose mechanism is re-entry.