Indications and Usage
Implantation of AnthemTM and Anthem RF devices is indicated for:
- Maintaining synchrony of the left and right ventricles in patients who have undergone an AV nodal ablation for chronic atrial fibrillation and haveNYHA Class II or III heart failure.
- The reduction of the symptoms of moderate to severe heart failure (NYHA Class III or IV) in those patients who remain symptomatic despite stable, optimal medical therapy, and have a left ventricular ejection fraction ≤ 35% and a prolonged QRS duration.
Implantation of Accent™, Accent RF, Anthem, and Anthem RF devices is indicated in one or more of the following permanent conditions:
- Or any combination of those symptoms
Rate-Modulated Pacing is indicated for patients with chronotropic incompetence,1 and for those who would benefit from increased stimulation rates concurrent with physical activity.
Dual-Chamber Pacing (Accent Model PM2110, Accent RF Model PM2210, Anthem, and Anthem RF devices only) is indicated for those patients exhibiting:
- Sick sinus syndrome
- Chronic, symptomatic second- and third-degree AV block
- Recurrent Adams-Stokes syndrome
- Symptomatic bilateral bundle branch block when tachyarrhythmia and other causes have been ruled out.
Atrial Pacing is indicated for patients with sinus node dysfunction and normal AV and intraventricular conduction systems.
Ventricular Pacing is indicated for patients with significant bradycardia and:
- Normal sinus rhythm with only rare episodes of A-V block or sinus arrest
- Chronic atrial fibrillation
- Severe physical disability
AF Suppression™ (Accent Model PM2110, Accent RF Model PM2210, Anthem and Anthem RF devices only) is indicated for suppression of paroxysmal or persistent atrial fibrillation episodes in patients with one or more of the above pacing indications.
For specific indications associated with individual modes, refer to the programmer’s on-screen help.
Implanted Cardioverter-Defibrillator (ICD). Accent, Accent RF, Anthem, Anthem RF devices are contraindicated in patients with an implanted cardioverter-defibrillator.
Rate-Adaptive Pacing may be inappropriate for patients who experience angina or other symptoms of myocardial dysfunction at higher sensor-driven rates. An appropriate Maximum Sensor Rate should be selected based on assessment of the highest stimulation rate tolerated by the patient.
AF Suppression (Accent Model PM2110, Accent RF Model PM2210, Anthem, Anthem RF devices only) stimulation is not recommended in patients who cannot tolerate high atrial-rate stimulation.
Dual-Chamber Pacing (Accent Model PM2110, Accent RF Model PM2210, Anthem, Anthem RF devices only), though not contraindicated for patients with chronic atrial flutter, chronic atrial fibrillation, or silent atria, may provide no benefit beyond that of single-chamber pacing in such patients.
Single-Chamber Ventricular Demand Pacing is relatively contraindicated in patients who have demonstrated pacemaker syndrome, have retrograde VA conduction, or suffer a drop in arterial blood pressure with the onset of ventricular pacing.
Single-Chamber Atrial Pacing is relatively contraindicated in patients who have demonstrated compromise of AV conduction.
For specific contraindications associated with individual modes, refer to the programmer’s on-screen help.
Warnings and Precautions
To prevent permanent damage to the device and tissue damage at the electrode/ tissue interface:
- Electrosurgery. Do not use electrosurgical devices in the vicinity of an implanted device. If electrocautery is necessary, use a bipolar cauterizer or place the indifferent electrode as far from the device as possible.
- Lithotripsy. Do not focus a lithotripsy beam within 6 inches of the device. Program the device to Sensor Off prior to lithotripsy to prevent inappropriate increases in pacing rate. A thorough assessment of device function with special attention to the sensor should be performed following exposure to lithotripsy.
- Therapeutic Radiation. Do not use ionizing radiation in the vicinity of an implanted device. Radiation therapy may damage the electronic circuitry of the device.
- Ultrasound Treatment. Do not use therapeutic ultrasound within 6 inches of the device.
- Ventricular Sensing. In Anthem and Anthem RF devices, Ventricular Sensitivity should be programmed to the highest setting (lowest sensitivity) that will provide ventricular sensing with adequate sensing margin. Left ventricular lead dislodgement, to a position near the atria, can result in atrial oversensing and ventricular inhibition.
Perform a thorough assessment of device function following exposure to any of the above.
Backup VVI Operation. In rare instances, the device may revert to Backup VVI operation at the programmed settings listed in Table 1. These values are not programmable.
When the device has reverted to Backup VVI operation, the programmer displays a pop-up message indicating that the device is operating at the Backup VVI values. Press [Continue] and follow the on-screen instructions.
|Ventricular Pacing Chamber
||LV - RV
||RV Unipolar Tip
LV Unipolar Tip
||RV Unipolar Tip
Table 1. Backup VVI Settings Elective Replacement Indicator (ERI). At ERI, the nominal life of the device is three months. When the device exhibits signs of ERI it should be replaced expeditiously. Patient follow-up visits should be scheduled at an appropriate frequency so that ERI can be detected well before End-of-Life (EOL). Noninvasive Programmed Stimulation (NIPS). Life-threatening ventricular tachycardia or fibrillation may occur during NIPS, therefore: (1) closely monitor the patient, and (2) make defibrillation and resuscitation equipment, and trained personnel, readily available during testing. Only physicians trained in tachycardia induction and reversion protocols should use NIPS. For more information on NIPS, refer to the programmer’s on-screen help. Ventricular Support Pacing during NIPS testing (Accent Model PM2110, Accent RF Model PM2210, Anthem, and Anthem RF devices only) is delivered in the VOO mode. The specific indications and contraindications for VOO mode can be found on the programmer’s on-screen help. Precautions For single use only.
Device Communication. Communication with the device can be affected by electrical interference and strong magnetic fields. If this is a problem, turn off nearby electrical equipment or move it away from the patient and the programmer. If the problem persists, contact St. Jude Medical. Suboptimal RF Communication.2 The Merlin® PCS indicates the quality of the RF communication by the telemetry strength indicator LEDs on both the programmer and the Merlin Antenna. Below is a list of potential causes to suboptimal radio communication:
The Merlin Antenna orientation/location is suboptimal.
Move or reorient the Merlin Antenna slightly. Make sure that the front of the Merlin Antenna faces the implantable device.
People or objects interfere with the communication between the merlin Antenna and the device.
Make sure that the space between the Merlin Antenna and the device is free from interfering objects/people.
The Merlin Antenna is too far away from the device.
Move the Merlin Antenna closer to the device.
Someone is holding the Merlin Antenna.
Place the Merlin Antenna on a flat surface. Do not hold the Merlin Antenna.
Other products in the vicinity are causing electromagnetic interference (EMI).
Power off or remove equipment that could cause EMI.
The Merlin Antenna cable is wound around the Merlin Antenna.
Make sure the Merlin Antenna cable is not wound around the Merlin Antenna. Table 2. Possible causes and solutions for suboptimal RF communication
CT scans, due to their increased power levels and long exposure times, have the remote possibility of interfering with implanted devices. The potential interference is transient and occurs only when the X-ray signal is present. Continuous exposure may cause a temporary sensor rate increase. In addition, there is a remote possibility for a device to intermittently oversense while the CT scanning beam is directly over the implanted device. Potential Adverse Events The following are potential complications associated with the use of any pacing system:
Air embolism Body rejection phenomena Cardiac tamponade or perforation Hematoma, bleeding hematoma, seroma Formation of fibrotic tissue, local tissue reaction Inability to interrogate or program due to programmer or device malfunction Infection/erosion Interruption of desired pulse generator function due to electrical interference, either electromyogenic or electromagnetic Lead malfunction due to conductor fracture or insulation degradation Loss of capture or sensing due to lead dislodgement or reaction at the electrode/tissue interface Loss of desired pacing and/or sensing due to lead displacement, body reaction at electrode interface, or lead malfunction(fracture or damage to insulation) Loss of normal device function due to battery failure or component malfunction Pacemaker migration or pocket erosion Pectoral muscle or diaphragmatic stimulation Phrenic nerve stimulation Pneumothorax/hemothorax Device migration and pocket erosion Endocarditis Excessive bleeding Induced atrial or ventricular arrhythmias Myocardial irritability Pericardial effusion Pericardial rub Pulmonary edema Rise in threshold and exit block Valve damage Cardiac/coronary sinus dissection (Anthem, Anthem RF devices only) Cardiac/coronary sinus perforation (Anthem, Anthem RF devices only) Coronary sinus or cardiac vein thrombosis (Anthem, Anthem RF devices only)
1. Chronotropic incompetence has not been rigorously defined. A conservative approach, supported by the literature, defines chronotropic incompetence as the failure to achieve an intrinsic heart rate of 70% of the age-predicted maximum heart rate or 120 min-1 during exercise testing, whichever is less, where the age-predicted heart rate is calculated as 197 — (0.56 x age). Gwinn N, Leman R, Kratz J, et al. Chronotropic incompetence: A common and progressive finding in pacemaker patients. American Heart Journal 1992; 123:1216-19.
2. Available in Accent RF and Anthem RF devices only.