First NZ patient to receive breakthrough heart device
First New Zealand patient to receive breakthrough heart device
World’s first implantable cardioverter defibrillator suitable for fullbody MRI scan
What: Clinicians based at Tauranga Hospital are amongst the first international experts to implant breakthrough technology which helps to prevent sudden cardiac death in those at risk, without denying access to fullbody MRI scanning in the future. The Medtronic Evera MRI system is the first device which detects and treats dangerously high heart rates (tachycardia)and also allows fullbody MRI scanning under certain conditions. .
Implantable cardioverter defibrillators (ICD) have played an important role in preventing sudden cardiac arrest, however until now, patients with devices have been unable to receive full body MRI scans because of potential interactions between the MRI and device function. These patients have relied on CT scans or xrays which can fail to detect the same level of detail for conditions including tumours, muscle damage, and other internal injuries.
It is estimated that as many as 63 percent of ICD patients will need an MRI within 10 years of receiving a device.[i] The heart of a person in tachycardia can pump between 100 to 400 beats per minute. At these elevated rates, the heart is not able to efficiently pump oxygenrich blood to the body, causing shortness of breath, chest pain, lightheadedness or loss of consciousness. In severe cases, it can cause heart attack or death, which is known as Sudden Cardiac Arrest (SCA).[ii] Each year, an estimated 4,000 New Zealanders will experience SCA with only 8 percent (320 people) surviving the event. Defibrillation is the only definitive treatment for SCA, and survival decreases 710 percent for every minute without it.[iii] Sudden cardiac arrest can affect anyone; however detection is possible through appropriate screening including longterm cardiac monitoring.
In brief: Tauranga Hospital is the first facility in New Zealand to implant the breakthrough technology compatible with fullbody MRI scanning which detects and delivers therapy for patients at risk of sudden cardiac arrest (SCA).
Each year 4,000 New Zealanders experience an SCA event with only an 8 percent survival rate. SCA risk can be detected through appropriate screening and once detected clinicians will generally recommend implantable cardioverter defibrillator (ICD) therapy consistent with the treatment guidelines by the Cardiac Society of New Zealand.
What this means to patients: Each year, only 8 percent of the estimated 4,000 New Zealanders who experience a sudden cardiac arrest (SCA) survive. For those who do, the likelihood of experiencing a future SCA is six times greater than the general population. Implantable Cardioverter Defibrillator (ICD) therapy has been in used in New Zealand to prevent SCA for more than 15 years.
It is estimated that as many as 63 percent of ICD patients will need an MRI within 10 years of receiving a device.[iv] Because no ICD system has yet been approved for MRConditional use, patients with devices have been contraindicated from receiving MRI scans due to the potential interactions between the MRI and the ICD.
About the technology: Compared to other ICDs available, the Evera MRI system gives patients the most unrestricted access to MRI scans, and ultimately allows them to get the diagnostic answers they need. The device is paired with the Sprint Quattro® Secure family of ICD leads, which has 10 years of performance data with active monitoring[v] and can be used in an MRI environment.[vi] The system provides clinicians and patients with increased longevity, improved comfort, and fullbody MRI access.
MRI scans allow physicians to make a wide range of health diagnoses by viewing highly detailed images of internal organs, blood vessels, muscle, joints, tumours, and areas of infection. MRI utilises strong magnetic fields and radio frequency pulses to create images of structures inside the body.
Implantable cardioverter defibrillator (ICD) therapy is used to treat tachycardia (a heart rate that is too fast). An ICD continuously monitors the heart. If a dangerous and potentially lifethreatening heart rate is detected, a painless electrical signal is sent to correct it. If the electrical signal fails to convert the arrhythmia, a shock is delivered to correct the potentially lethal rhythm. In addition to the device, one or more leads (tiny insulated wire) are implanted to carry information signals from the heart to the ICD and when necessary, to carry electrical impulses to the heart.
About Tachycardia/Sudden cardiac arrest: Tachycardia is the term for a fast heart rate, more than 100 beats per minute and as many as 400 beats per minute. At these elevated rates, the heart is not able to efficiently pump oxygenrich blood to the body, causing shortness of breath, chest pain, lightheadedness or loss of consciousness. In severe cases, it can cause heart attack or death, which is known as Sudden Cardiac Arrest (SCA).[vii] Tachycardia can occur in either the upper or lower heart chambers. Causes of tachycardia include, but aren’t limited to, heart related conditions such as hypertension (highblood pressure), poor blood supply to the heart muscle due to coronary artery disease, heart failure, heart muscle disease, tumours or infections.viii
i Turakhia M, Reynolds M, Wolff S, et al. Medtronic Data on File 2013. Data from 2011 MarketScan® Commercial and Medicare database, Truven Analysis, Inc. were used for this research. Patient cohort represents ICD patients in terms of age, gender, and major comorbidities (N = 10,778).
ii http://www.heart.org/idc/groups/heart-public/@wcm/@hcm/documents/downloadable/ucm_300290.pdf Accessed 24 Jan 2013
iii American Heart Association. AHA Scientific Position – Sudden Cardiac Death. Available at http://www.americanheart.org/presenter.jhtml?identifier=4741.
iv Turakhia M, Reynolds M, Wolff S, et al. Medtronic Data on File 2013. Data from 2011 MarketScan® Commercial and Medicare database, Truven Analysis, Inc. were used for this research. Patient cohort represents ICD patients in terms of age, gender, and major comorbidities (N = 10,778).
v Medtronic Product Performance Report, 2012 Second Edition, Issue 66.
vi Models 6935M (55cm, 62cm) and 6947M (55cm, 62cm)
vii http://www.heart.org/idc/groups/heart-public/@wcm/@hcm/documents/downloadable/ucm_300290.pdf Accessed 24 Jan 2013
Accessed 24 Jan