Medtronic announced today that the FDA had approved its Advisa DR MRI SureScan, a next generation pacemaker system specifically designed and tested for use with MRI scanners. The system, which Medtronic said would be launched immediately, includes the Advisa MRI device and two CapSureFix MRI SureScan leads.
Unrecognized myocardial infarction (UMI) is more prevalent, and is associated with a worse prognosis, than may be generally understood, according to a new study published in JAMA.
Studying an elderly (67-93 years of age) population in Iceland, Erik Schelbert and colleagues used ECG and cardiac magnetic resonance (CMR) to detect UMI. CMR was more effective than ECG at detecting UMI. The study established that UMI was twice as prevalent as recognized MI (RMI):
- No MI: 74%
- RMI: 10%
- Unrecognized MI by ECG: 5%
- Unrecognized MI by CMR: 17%
Diabetics were more likely to have UMI detected by CMR than by ECG. After 6.4 years of followup, mortality was higher in the RMI and UMI groups than in the group without MI:
- RMI: 33% (CI 23% to 43%)
- UMI: 28% (CI 21% to 35%)
- No MI: 17%, (CI 15% to 20%)
After adjusting for other factors, UMI by CMR, but not UMI by ECG, significantly improved risk stratification for mortality. People with UMI by CMR were less likely than people with RMI to take cardiac drugs.
According to the authors, the large percentage of UMIs has not been understood in the past due to previous reliance on ECG data; thus “a significant public health burden” has not been fully appreciated.