MRI SureScan™ ICDs

Cobalt™/Crome™ MRI SureScan™ ICD and CRT-D Systems

Indications

The Cobalt and Crome HF CRT-D MRI SureScan systems are indicated for use in patients who are at significant risk of developing atrial and/or life-threatening ventricular arrhythmias and who have heart failure with ventricular arrhythmias. Heart failure patients must have experienced one or more of the following conditions:

• NYHA Functional Class III or IV patients who remain symptomatic despite stable, optimal medical therapy and have LVEF ≤ 35% and a prolonged QRS duration
• NYHA Functional Class II patients who have left bundle branch block (LBBB) with a QRS duration ≥ 130 ms and a left ventricular ejection fraction ≤ 30%
• NYHA Functional Class I, II, or III who are on stable, optimal medical therapy (if indicated) and have LVEF ≤ 50%, atrioventricular block (AV block), and are expected to require a high percentage of ventricular pacing that cannot be managed with algorithms to minimize right ventricular pacing. 

The Cobalt and Crome VR and DR ICD MRI SureScan systems are indicated for the automated treatment of patients who have experienced, or are at significant risk of developing, atrial and/or life-threatening ventricular arrhythmias through the delivery of antitachycardia pacing, cardioversion, and defibrillation therapies.

MRI Conditions for Use

Medtronic SureScan ICD and CRT-D systems are MR Conditional, and as such are designed to allow patients to undergo MRI under the specified conditions for use. ICD and CRT-D SureScan system patients may be scanned using a horizontal field, cylindrical bore, clinical 1.5T or 3T MRI system for hydrogen proton imaging. When programmed to On, the MRI SureScan feature allows the patient to be safely scanned while the device continues to provide appropriate pacing. A complete SureScan defibrillation system, which is a SureScan device with appropriate SureScan lead(s), is required for use in the MR environment. To verify that components are part of a SureScan system, visit http://www.mrisurescan.com/. Any other combination may result in a hazard to the patient during an MRI scan.

Contraindications

The Cobalt and Crome VR and DR ICD, and CRT-D MRI SureScan systems are contraindicated for use in the following situations:

• If implanted with a unipolar pacemaker
• If incessant VT or VF exists
• If the primary disorder is chronic atrial tachyarrhythmia with no concomitant VT or VF
• If tachyarrhythmias with transient or reversible causes exist, including the following known issues: acute myocardial infarction, drug intoxication, drowning, electric shock, electrolyte imbalance, hypoxia, and sepsis

Warnings and Precautions

Changes in a patient’s disease and/or medications may alter the efficacy of thedevice’s programmed parameters. Patients should avoid sources of magnetic and electromagnetic radiation to avoid possible underdetection, inappropriate sensing and/or therapy delivery, tissue damage, induction of an arrhythmia, device electrical reset, or device damage. Do not place transthoracic defibrillation paddles directly over the device. 

Patients and their implanted systems must be screened to meet the following requirements for MRI: no lead extenders, lead adaptors, or abandoned leads present; no broken leads or leads with intermittent electrical contact as confirmed by lead impedance history; the device must be operating within the projected service life; and the system must be implanted in the left or right pectoral region.

Potential Adverse Events

Potential adverse events include, but are not limited to, the following events: allergic reactions, atrial fibrillation, bradyarrhythmia, cardiac arrest, device migration, discomfort, dizziness, dyspnea, erosion, excessive fibrotic tissue growth, heart failure or loss of CRT (for CRT-D patients), hematoma, hemorrhage, inability to deliver therapy, inappropriate shock, infection, lead migration/dislodgement, lethargy, loss of pacing, mental anguish, necrosis, nerve damage, oversensing, palpitations, seroma, syncope, tachyarrhythmia, tissue damage due to heating of the device, undersensing, and wound dehiscence. 

Potential MRI complications include, but are not limited to, lead electrode heating and tissue damage resulting in loss of sensing or capture or both, spontaneous tachyarrhythmia, potential for VT/VF induction, device heating that results in tissue damage, stimulation of the leads that results in continuous capture, VT/VF, hemodynamic collapse, damage to the device or the leads, causing the system to fail or treat the patient’s condition incorrectly, and movement or vibration of the device or the leads, resulting in dislodgement.

See the device manuals for detailed information regarding the implant procedure, indications, contraindications, warnings, precautions, and adverse events. See the MRI SureScan Technical Manual before performing an MRI Scan. For further information, call Medtronic at 1-800-328-2518 and/or consult the Medtronic website at medtronic.com or mrisurescan.com.

Caution: Federal law (USA) restricts these devices to sale by or on the order of a physician.

Visia AF™ and Visia AF MRI SureScan™ VR Models

The Visia AF and Visia AF MRI SureScan ICD systems automatically detect and record the occurrence of atrial fibrillation (AF) for diagnostic purposes. The AF Detection feature analyzes variability in the ventricular rate to determine whether the patient is currently experiencing atrial fibrillation. Evidence of atrial fibrillation is based on ventricular rate variability assessed via a Lorenz plot.

The Visia AF MRI VR SureScan ICD Models are MR Conditional and, as such is designed to allow patients to be safely scanned by an MRI machine when used according to the specified MRI conditions for use. When programmed to On, the MRI SureScan feature allows the patient to be safely scanned while the device continues to provide appropriate pacing.

Indications for Use

The Visia AF and Visia AF MRI SureScan ICD systems are indicated to provide ventricular antitachycardia pacing and ventricular defibrillation for automated treatment of life-threatening ventricular arrhythmias.

A complete Visia AF MRI SureScan defibrillation system is required for use in the MR environment. A complete Visia AF MRI SureScan defibrillation system includes a Visia AF MRI VR SureScan ICD device (Model DVFB1D4 or DVFB1D1) with a SureScan defibrillation lead. When a single coil SureScan defibrillation lead is used, a Medtronic DF-1 pin plug must be secured in the SVC port to make a complete SureScan DF-1 defibrillation system. To verify that components are part of a SureScan system, visit http://www.mrisurescan.com. Any other combination may result in a hazard to the patient during an MRI scan.

Contraindications

The Visia AF ICD is contraindicated for patients experiencing tachyarrhythmias with transient or reversible causes including, but not limited to, the following: acute myocardial infarction, drug intoxication, drowning, electric shock, electrolyte imbalance, hypoxia, or sepsis; patients who have a unipolar pacemaker implanted, patients with incessant VT or VF, and patients whose primary disorder is atrial tachyarrhythmia.

Warnings and Precaution

Changes in patient’s disease and/or medications may alter the efficacy of the device’s programmed parameters. Patients should avoid sources of magnetic and electromagnetic radiation to avoid possible underdetection, inappropriate sensing and/or therapy delivery, tissue damage, induction of an arrhythmia, device electrical reset, or device damage. Do not place transthoracic defibrillation paddles directly over the device.

For Visia AF MRI System only:

Patients and their implanted systems must be screened to meet the following requirements for MRI: no implanted lead extenders, lead adaptors, or abandoned leads; no broken leads or leads with intermittent electrical contact as confirmed by lead impedance history; a SureScan defibrillation system implanted in the left or right pectoral region; pacing capture thresholds of ≤ 2.0 V at a pulse width of 0.4 ms; no diaphragmatic stimulation at a pacing output of 5.0 V and at a pulse width of 1.0 ms in patients whose device will be programmed to an asynchronous pacing mode when MRI SureScan is programmed to On.

Patients may be scanned using a horizontal field, cylindrical bore, clinical 1.5T or 3T MRI system for hydrogen proton imaging, maximum spatial gradient ≤ 20 T/m, and maximum gradient slew rate performance per axis ≤ 200 T/m/s. 1.5T scanners must be operated in Normal Operating Mode (whole body averaged specific absorption rate (SAR) ≤ 2.0 W/kg, head SAR ≤ 3.2 W/kg). 3T scanners must be operated in First Level Controlled Operating Mode or Normal Operating Mode. B1+RMS must be ≤ 2.8 μT when the isocenter (center of the bore) is inferior to the C7 vertebra. Scans can be performed without B1+RMS restriction when the isocenter is at or superior to the C7 vertebra.

Continuous patient monitoring is required while MRI SureScan is programmed to On. While MRI SureScan is programmed to On, arrhythmia detection and therapies are suspended, leaving the patient at risk of death from untreated spontaneous tachyarrhythmia. In addition, if the device is programmed to an asynchronous pacing mode, arrhythmia risk may be increased.

Potential Complications

Potential complications include, but are not limited to, rejection phenomena, erosion through the skin, muscle or nerve stimulation, oversensing, failure to detect and/or terminate tachyarrhythmia episodes, acceleration of ventricular tachycardia, and surgical complications such as hematoma, infection, inflammation, and thrombosis. Other potential complications related to the lead may include lead dislodgement, lead conductor fracture, insulation failure, threshold elevation, or exit block.

Potential MRI complications for the Visia AF MRI SureScan system include, but are not limited to, lead electrode heating and tissue damage resulting in loss of sensing or capture or both, or induced currents on leads resulting in continuous capture, VT/VF, and/or hemodynamic collapse; spontaneous tachyarrhythmia occurring during the scan that

is not detected and treated because tachyarrhythmia detection is suspended while MRI SureScan is programmed to On; potential for VT/VF induction when the patient is programmed to an asynchronous pacing mode during MRI SureScan; device heating resulting in tissue damage in the implant pocket or patient discomfort or both; or damage to the functionality or mechanical integrity of the device resulting in the inability of the device to communicate with the programmer.

See the Device Manual for detailed information regarding the implant procedure, indications, contraindications, warnings, precautions, and potential complications/adverse events for all Visia AF devices and the MRI SureScan Technical Manual before performing an MRI Scan on patients with a Visia AF MRI system.  For further information, please call Medtronic at 1-800-328-2518 and/or consult Medtronic’s website at www.medtronic.com or www.mrisurescan.com.

Caution:  Federal law (USA) restricts this device to sale by or on the order of a physician.

Sprint Quattro MRI™ SureScan™ Leads (Models 6935M and 6947M) for 1.5 and 3T

Indications

Medtronic Sprint Quattro leads are intended for pacing and sensing and/or defibrillation. Defibrillation leads have application for patients for whom implantable cardioverter defibrillation is indicated.

The Sprint Quattro MRI SureScan Leads (55 cm and 62 cm lengths of Models 6935M or 6947M) are part of the Medtronic SureScan defibrillation system. A complete SureScan defibrillation system is required for use in the MR environment and includes a Medtronic SureScan device connected to Medtronic SureScan Leads. 

Contraindications

• ventricular use in patients with tricuspid valvular disease or a tricuspid mechanical heart valve
• patients for whom a single dose of 1.0 mg of dexamethasone acetate and dexamethasone sodium phosphate may be contraindicated

Warnings and Precautions

Potential Complications

Sprint Quattro™ Leads

Indications

Contraindications

• ventricular use in patients with tricuspid valvular disease or a tricuspid mechanical heart valve.
• for the sole use of detection and treatment of atrial arrhythmias.
• for patients with transient ventricular tachyarrhythmias due to reversible causes (drug intoxication, electrolyte imbalance, sepsis, hypoxia) or other factors (myocardial infarction, electric shock).
• patients for whom a single dose of 1.0 mg of dexamethasone acetate and dexamethasone sodium phosphate may be contraindicated

Warnings/Precautions

People with metal implants such as implantable cardioverter defibrillators (ICDs) and accompanying leads should not receive diathermy treatment, except for therapeutic ultrasound. The interaction between the implant and diathermy can cause tissue damage, fibrillation, or damage to the device components, which could result in serious injury, loss of therapy, or the need to reprogram or replace the device. 

Do not use magnetic resonance imaging (MRI) on patients who have non-MR conditional versions/lengths of these leads implanted as part of a complete SureScan System. MRI can induce currents on implanted leads, potentially causing tissue damage and the induction of tachyarrhythmias.

Potential Complications