NEW YORK (Reuters Health) – Cardiac magnetic resonance (CMR) stress perfusion imaging for possible ischemia provides “robust” prognostic information regardless of patient sex, new research indicates.
In the August issue of JACC: Cardiovascular Imaging, Dr. Raymond Y. Kwong, from Brigham and Women’s Hospital, Boston and colleagues say they’ve observed a strong association between CMR-detected ischemia and hard cardiac events in both men and women.
CMR, they conclude, is a “highly promising alternative noninvasive prognosticating tool that overcomes the limitations of other techniques in imaging women with suspected myocardial ischemia.”
Women with heart disease typically fare worse than men owing to later detection and treatment. Women are more apt to present with atypical symptoms, have a higher burden of microvascular dysfunction and are less likely to perform an adequate exercise test due to comorbidities. They are also more difficult to image due to smaller heart size and breast attenuation.
CMR is “appealing” to image women at risk because it provides noninvasive characterization of myocardial ischemia and infarction at high spatial resolution, is relatively free of attenuation artifacts and does not involve ionizing radiation, Dr. Kwong and colleagues say.
Yet there’s been some uncertainty about whether this technique works as well in women as in men.
To investigate, Dr. Kwong and colleagues assessed the prognostic value of stress CMR in a consecutive cohort of 405 patients referred for ischemia assessment. The cohort included 168 women. The CMR test consisted of cine cardiac function, perfusion imaging during vasodilating stress, and late gadolinium enhancement imaging.
During a median follow up of 30 months, 36 patients (9%) suffered a major cardiac event, including 21 cardiac deaths and 15 acute heart attacks.
In women, CMR evidence of ischemia was strongly associated with major cardiac events, with an unadjusted hazard ratio of 49.9 (P < 0.0001).
The annual event rate was 15% in women with CMR evidence of ischemia compared with 0.3% in women without CMR evidence of ischemia, which is similar to the rate seen in men without CMR evidence of ischemia (1.1%).
For both men and women, CMR myocardial ischemia score was the strongest multivariable predictor of major adverse cardiac events.
These results, the investigators say, indicate that the prognostic value of stress CMR for major cardiac events is “excellent” regardless of patient sex.
J Am Coll Cardiol Img 2011;4:850-861.