What are the dangerous signs on Holter monitoring? Cardiology Basics

What are the dangerous signs on Holter monitoring? Cardiology Basics

Holter monitoring is an ambulatory ECG monitoring, usually with a digital recorder, attached to a belt, typically for 24 to 48 hours. Two or three channels are usually recorded with an appropriate number of patch electrodes attached to the chest. Holter monitoring is usually done when a cardiac arrhythmia as the cause of symptoms is suspected. It can also be done to detect atrial fibrillation as part of post stroke workup.

Dangerous signs to look for on a Holter tracing are life threatening tachy and bradyarrhythmias. Here is a long pause which could cause syncope. This is a long sinus pause in sick sinus syndrome. Symptomatic long pauses in sick sinus syndrome will benefit from implantation of a pacemaker. Implantation of pacemaker in sick sinus syndrome will improve the quality of life.

This ECG shows complete heart block. There are regular P waves and QRS complexes, but atrial rate is higher than the ventricular rate. There is no relation between P and QRS complexes, as evidenced by the totally varying PR intervals. These are the four criteria for the diagnosis of complete heart block in an ECG. Acquired complete heart block is an indication for pacemaker implantation regardless of symptomatic status as it carries a high risk of adverse events and harm.

This ECG shows a fast ventricular tachycardia which needs prompt treatment. If it is not responding to medications, a synchronized electrical cardioversion is needed. Cause has to be identified and treated along with it. Reversible causes like electrolyte abnormalities and ischemia do not mandate long term antiarrhythmic therapy. Some cases may need radiofrequency catheter ablation and implantable cardioverter defibrillator.

Most dangerous cardiac arrhythmia is ventricular fibrillation, shown in this ECG strip. The person will be in cardiac arrest and will die unless immediate defibrillation is given. Cardiopulmonary resuscitation has to be given till a defibrillator is available. In case of ventricular fibrillation noted on Holter monitoring, it will not be treatable unless it occurs while in hospital or a bystander is available for immediate cardiopulmonary resuscitation and follow up action. In such situations it is a retrospective review of Holter data.

This ECG shows multiple ventricular ectopics of different morphologies showing a high irritability of the ventricles. Risk for development of sustained ventricular tachycardia and sometimes ventricular fibrillation is high. Ventricular tachycardia if it occurs in this scenario, could be fast polymorphic ventricular tachycardia known as torsades de pointes.

Here we can see the diagram of a temporary pacemaker and X-ray of a person with permanent pacemaker. Temporary pacemaker is installed outside the body and connected to the cardiac chambers through leads introduced through femoral or jugular vein, to treat symptomatic but reversible bradyarrhythmias. Permanent pacemaker is usually implanted subcutaneously and the leads are taken to the cardiac chambers through a subclavian vein puncture. Here it is a dual chamber pacemaker with a lead each in the right atrium and right ventricle.

This picture shows an automated external defibrillator (AED) for use by minimally trained persons in public places like malls, railway stations and airports. Once the electrode patches are applied over the chest, it analyses the cardiac rhythm and gives audio prompts. If a shockable rhythm is detected, a shock is advised, which the bystander can deliver. In case of non-shockable rhythms, the device advises continuation of cardiopulmonary resuscitation.