Atypical chest pain, that has lasted for about 3 hours, stable.
She complains of fatigue and palpitations when exercising, however with no chest pain.
Smoker since 23 y.o.
Non diabetic.
Normal levels of blood pressure and cholesterol.
No history of CAD.
BMI 27, HR 78 bpm, BP 145/90 mmHg, normal chest examination, other wise unremarkable.
Basal EKG: pre-excitation syndrome. Cardiac enzymes including serum Troponine levels are within normal limits.
Basal echocardiogram: mild mitral valve prolapse, with preserved global and regional ventricular function.
Teaching points:
Attenuation is a common artifact in myocardial perfusion imaging, being present in 20-30% of cases, mimicking the presence of MI.
Breast attenuation causes pseudo-defects on the anterior wall of the left ventricle, and is more evident in women with lage breasts. However, it can be also significant in women with small but dense breasts. In men, diaphragmatic attenuation is more common, affecting the inferior wall - especially in obese patients.
Attenuation correction is possible using external sources or CT, but these are expensive solutions. Prone imaging can be used mainly for inferior wall artifacts.
Gated SPECT provides information about regional wall motion and thickening, which would be affected by infarction but preserved when attenuation is present.
Visualization of raw data can also aid in depicting attenuation.
