The CRT structure contains two modules: a pulse generator, or a device, and a thin, insulated wire called a conductor. A CRT device provides tiny quantities of electrical energy to the heart through these lines. his helps to restore the standard timing of the heartbeat, which causes both ventricles to pump around each other more effectively as the fist usually closes again. While working as a normal pacemaker to handle slow heart rhythms, the CRT-P device also provides tiny electrical impulses to the left and right ventricles to assist them to contract at the very same time to make your heart pump more effectively.

Like any battery, the battery in your CRT-P or CRT-D will run out of overtime. Since the battery is perpetually sealed inside your device, it cannot be replaced when its energy is exhausted. So, if your battery is running out, your complete device needs to be replaced. The battery life varies based on the settings of your doctor's programs and how much treatment you obtain. 

Single chamber pacemaker (VVI)

The ventricle is recognized, and if it generates a QRS, the pacemaker stays silently and wait patiently. The VVI pacemaker will only fire if there has been no electrical ventricular action within the range limits established by its predefined frequency. Yes, with the build-up of in only one chamber, you may have only the option of AAI or AOO if it is in the atrium or VOO or VVI if it is in the ventricular. Deactivated modalities such as AAT and VVT are also accessible. Ingle chamber atrial speed is usually prescribed in the existence of AV absorption abnormalities. Sure, the atrium may do its job, but the ventricular will not-and your cardiac rate will still be a delayed "native" ventricular tempo. Worse yet if you edge the atrium in the existence of AV conduction failings, the left atrium will arrange against the confined mitral valve, mailing the blood pulse away into the center venous circulatory system. Atrial speeding generally does not tend to work in the existence of atrial fibrillation, especially if it is severe. A vast dilated atrium with irrelevant conduction fibers will have no better chance of organizing its stimulation with the pacemaker than it did with the sinoatrial module.

Dual-chamber pacemaker (DDDR)

Dual-chamber, rate-modulated pacing (DDDR) has only recently been made available. During exercise, the pacemaker is capable of tracking not only the patient's intrinsic P wave but also the AV sequential sensor-indicated rate response, which depends on the programmed variables of the specific sensor in the DDDR pulse generator. Programmed options that affect the operation of a rate-modulated DDDR device are slope, threshold, reaction time, and recovery time. In addition, one is required to program a base or minimum pacing rate and a maximum tracking rate, as in any DDD device, as well as a maximum sensor rate. It is essential to know and understand all these programmed options if one is to correctly interpret electrocardiograms from a DDDR pacemaker. Interpreting the electrocardiograms also requires an understanding of the sensor-indicated rate of the pacemaker at any given level of exercise, which is determined by the options previously listed and the interaction between the sensor-indicated rate and the patient's intrinsic atrial and ventricular activity. This paper presents electrocardiograms typical of a new DDDR pacemaker undergoing clinical investigation.

AICD

An implantable cardioverter defibrillator (ICD or AICD) is a permanent device in which a lead (wire) inserts into the right ventricle and monitors the heart rhythm. It is implanted similar to a single chamber pacemaker and the generator lays in the upper chest area and venous access is through the subclavian vein. Therapies are delivered in the form of anti-tachycardia pacing (ATP) or shocks to convert to sinus rhythm from sustained ventricular tachycardia or ventricular fibrillation, both of which are life-threatening rhythms.