IBHRE CCDS key terms

The smallest intrinsic intracardiac electrogram amplitude that a device reliably detects as a cardiac event at the programmed sensitivity setting, measured in millivolts during testing.

The programmed voltage level above which a device counts an electrical signal as a sensed event; lowering the number makes the device more sensitive to small signals.

The minimum stimulus energy, usually expressed in volts or milliamps at a given pulse width, that consistently produces cardiac depolarization when the heart is paced.

A plot of the minimum current or voltage needed for capture at each pulse width, showing that shorter pulses require higher output to depolarize myocardium.

The duration of each pacing stimulus, typically programmed in milliseconds; longer widths lower threshold but consume more battery energy.

Depolarization of the myocardium produced by a pacing stimulus, confirmed on ECG by a P wave or QRS complex following the pacing artifact.

A pacing artifact that fails to produce a resulting P wave or QRS complex, indicating lead dislodgement, elevated threshold, insulation failure, or depleted output.

Failure of the device to detect an intrinsic cardiac event because the signal falls below the programmed sensitivity, which can lead to inappropriate pacing during the cardiac cycle.

Detection of electrical signals that are not true cardiac depolarizations, such as T waves, myopotentials, or electromagnetic interference, causing inappropriate inhibition or counting.

Detection by an atrial or ventricular channel of depolarization originating in the opposite chamber, because the signal is large enough to exceed that channel's sensitivity setting.

An atrial lead sensing the ventricular pacing stimulus, or a ventricular lead sensing the atrial stimulus, which can trigger inappropriate inhibition or mode switching.

A brief programmed interval after a paced or sensed event during which the device ignores input on a channel to prevent oversensing of its own output or the opposite chamber's signal.

A time window after a sensed or paced event during which the device does not respond to further signals on that channel, though it may still count them for rate purposes.

The slowest pacing rate the device will deliver in a given mode, programmed to match the patient's expected physiologic needs at rest.

The fastest rate at which a dual-chamber device will pace the ventricle in response to sensed atrial events, protecting against rapid ventricular pacing during atrial tachyarrhythmias.

An automatic change from a tracking mode such as DDD to a non-tracking mode such as DDI when the device detects an atrial tachyarrhythmia, preventing rapid ventricular pacing.

A programmable feature that allows the paced rate to fall below the lower rate limit after a sensed event, promoting intrinsic conduction before pacing resumes.

A sensor-driven feature that raises the pacing rate during exertion or stress, typically using minute ventilation, accelerometer, or impedance-based sensors.

The inability of the sinus node to increase heart rate appropriately with metabolic demand, a common indication for rate-responsive pacing.

The programmed interval between an atrial event and the subsequent ventricular pacing stimulus, adjusted to optimize filling and avoid unnecessary ventricular pacing.

A protective feature that delivers a ventricular pacing stimulus shortly after an atrial event when crosstalk is suspected, preventing inappropriate inhibition of ventricular output.

Intraprocedural delivery of a test shock to confirm that the ICD can reliably terminate induced ventricular fibrillation at the programmed energy setting.

Programmed rate intervals that classify sensed ventricular events as ventricular tachycardia or ventricular fibrillation, determining which therapy the device delivers.

Delivery of rapid pacing bursts through the ICD lead to terminate ventricular tachycardia without a shock, reducing patient discomfort and battery drain.

The electrical resistance measured across the defibrillation pathway, used to confirm lead integrity and adequate coil-to-can contact before and after shock delivery.

The resistance measured along a pacing lead, typically 300 to 1000 ohms; values outside this range suggest fracture, insulation breach, or dislodgement.

Movement of a lead tip away from its intended myocardial site, producing loss of capture, rising thresholds, or altered sensing on the affected channel.

Collection of blood around the device pocket after implantation, which can cause wound breakdown, infection, or device erosion if not recognized and managed.

Bacterial infection of the device pocket, often requiring system extraction and antibiotic therapy; signs include erythema, drainage, and fever.

Gradual wearing of the device or lead through the skin, typically from pressure, thin tissue, or infection, requiring surgical revision or system removal.

The route used to introduce pacing or ICD leads, commonly the subclavian, cephalic, or axillary vein, chosen based on anatomy and risk of lead crush.

Air in the pleural space, a recognized complication of subclavian venous access during device implantation, presenting with chest pain and dyspnea.

Placing a magnet over a device to trigger a preset behavior, such as asynchronous pacing in pacemakers or suspension of tachycardia therapy in ICDs, for procedures or troubleshooting.

External electrical noise from sources such as electrosurgery, MRI, or welding that can be oversensed by a device, causing inhibition, inappropriate pacing, or spurious shocks.

A pacemaker or ICD system approved for scanning under specified magnetic field, lead configuration, and programming conditions, with post-scan interrogation and reprogramming required.

Transmission of device diagnostics and arrhythmia data from home to a clinical center, enabling early detection of lead problems and clinical events between visits.

Retrieval of stored device data and programmed parameters using a programmer, forming the basis for follow-up assessment and reprogramming decisions.