Electrophysiology from Bard International

Invasive Interventional Cardiology treats cardiac patients inside the cardiac catheterization laboratory for problems, which are broadly classified clinically as of two types.

1. Blockages of coronary arteries: Plaque gets accumulated in the arteries that supply fresh blood to the heart for its functioning as a blood pump for the human body. This is treated by inserting the balloon catheters and also placing a metal stent inside the arteries.

2. Irregularities in the electrical system of the heart:

In order for the smooth running of the heart (to pump oxygenated blood throughout the body), it needs an electrical impulse to generate a heart beat which transmits or travels inside the heart resulting in the contraction of heart which precipitates the actual pumping of blood.

If this electrical impulse is not generated or not transmitted properly inside the heart, it affects the pumping of blood to the body, which is the main function of the heart. These type of problems are treated by implanting a pacemaker/ICD (internal cardiac defibrillator) or through an electro-physiology study.

These classifications of patients complains of chest pain, palpitations, dizziness and fainting etc as the symptoms and if left unattended can lead to complications. In a severely untreated case the heart rate can become abysmally low or very fast resulting in sudden death.

In electrophysiology treatment multiple catheters are placed inside the heart chambers to record the electrical potential at different locations inside the heart. These electrical signals from different heart locations are displayed, recorded and measured on the electrophysiology recording system.

Along with a cardiac pacing stimulator the symptoms are regenerated and finally cured by giving RF energy to burn the mis-behaving tissue inside the heart. The electrophysiology recording system is the main equipment used for complete duration of the case with the catheters being connected to this equipment, displaying and recording continously signals from different locations inside the heart chambers, doing calculations on the signals, delivering pacing spikes (generated from the stimulator) through the recording system to the catheters, deciding the location where RF energy is to be delivered. After the culprit tissues are burnt with energy, the patient is retested through the equipment before discharging from the cardiac catherization laboratory.

Functions of different equipments used in the electrophysiology treatment.

Cardiac catherization laboratory is used to display the X-ray image of the electrophysiology catheter placed inside the heart. Electrophysiology recording system is used to connect electrophysiology catheters placed at different locations inside the heart chambers.

Display, record, perform calculations on the electrical signals from these catheters on continous real time basis. Deliver stimulus/pacing spike to recreate the clinical problem being faced by the patient.

Map the exact location of heart tissues where RF energy burns are to be delivered.

Retest the patient with display, record and calculations before the patient is discharged.

Cardiac pacing stimulator is used to generate programmed pacing spike and pass on to the recording system.

RF Generator is used to generate RF Energy and pass on RF ECG signals to the recording system.

Types of arrhythmia treated by electrophysiology:

• Sinus bradycardia
• Premature atrial contractions
• Atrial flutter
• Atrial fibrillation
• Premature ventricular complex
• Ventricular tachycardia
• Ventricular fibrillation
• Re-entrant tachycardia
• Abnormal automaticity
• Accessory pathways
• Right sided pathways
• Septal Pathways
• Left sided pathways
• A V nodal pathways
• Fascicular ventricular pathways
• Atrio fascicular pathways
• Intranodal bypass tracts
• Wolfe-parkinson-white syndrome
• Sinoatrial conduction time
  

Criteria for purchasing an appropriate labsystem:

Signal quality of amplifier:

In electrophysiology set-up the complete diagnosis and treatment of the patient is performed by looking at intracardiac ECG signals being displayed and recorded by the EP recording system. So the intracardiac signal quality is the utmost important feature for an EP labsystem.

Signal quality is determined by analog to digital chip being used and the maximum sampling rate being offered by the equipment. 16 bit chip gives 24 = 16 times better signal quality than a 12 bit chip.

Superior amplifier

Modular is better than non-modular.

With non modular you will need to replace the complete amplifier and purchase a new amplifier to add more channels or advanced features.

Superior CPU

Server based CPU are superior than PC based CPU. DVD Patient data archiving is the latest in thing these days replacing the optical disk media.

Multitasking -the capability to perform multiple tasks simultaneously without slowing down the system is vital for EP system because of the amount of data being handled and large number of channels. Look for better chip, fast speed and bigger hard disk capacity.

Look for exclusive software algorithms:

• Template matching analysis l Mapping graph bar
• T-wave subtraction algorithm
• Stim detection and analysis
• Ablation data display
• Flouro option
• Medication protocol
• Power point and JPEG data
• Review and post analysis trigger and holter features.

After sales support: In addition to after sales technical support, electrophysiology needs a lot of application and educational support. Prefer a supplier with a long track record and ongoing programs for providing both application training and educational support to the physicians. Prefer the company that manufactures both EP recording systems and complete range of EP and pacing catheters.

From the archives of Bard International, South Asia, Electrophysiology Training Programme, India