Myocardial Ischemia Detection With a Combined Cardiovascular Magnetic Resonance and Biomarker Protocol

Background:

Early detection and treatment of coronary artery disease (CAD) can help curb the high incidence of cardiovascular disease, which is the leading cause of death worldwide. Today, we have sophisticated imaging techniques available to diagnose CAD, including cardiovascular magnetic resonance (CMR). CMR is able to detect relevant myocardial ischemia and guide treatment options. Therefore, it is recommended by the current guidelines for patients at intermediate risk. In clinical practice, we often encounter two main issues: first, because of their availability and increasing uncertainty in the population, imaging techniques are increasingly used, even in patients with a low pretest probability for the presence of CAD. Second, the diagnostic accuracy of the techniques is not perfect, and false-negative stress CMR perfusion studies are an important limitation of the method, especially in patients with advanced CAD and balanced ischemia. In addition, the standard method with pharmacologic testing carries an inherent risk.

Aim:

The aim of our project is to review the clinical pretest probability to reduce unnecessary imaging studies and to evaluate the improvement of diagnostic accuracy of CMR stress testing by adding exercise test and reviewing biomarkers, which could reduce the number of false-negative results, especially in patients with balanced ischemia, who usually suffer from severe CAD.

Methodology:

This is a prospective, randomized, two-arm, controlled, monocentric, national study performed in collaboration by two centers (Solothurner Spitäler AG and CRIB). Included are consecutive patients with suspected inducible myocardial ischemia who are examined by CMR at the Kantonsspital Olten and during the course also at the Bürgerspital Solothurn. Since all patients from the Kanton Solothurn are referred to us for CMR diagnosis, this represents an ideal referral pattern of unselected patients with a wide range of pretest probability for myocardial ischemia (interquartile range of pretest probability 20-60%). Patients able to exercise will randomized to either standard CMR stress protocol with regadenoson or to the combined CMR stress protocol, which includes additional exercise testing and measurement of hs-cTn, a biomarker for detecting myocardial damage. Patients with positive CMR results will be received to coronary angiogram.

Potential Significance:

This project has the potential to reduce the residual risk and thereby reduce cardiovascular mortality in patients with false-negative test result, especially those with balanced ischemia or inadequate response to vasodilatation drugs. In addition, the investigator will be able to make a statement about the additional use of biomarkers for the diagnosis of CAD in patients with stable condition. Thereby, the integrated use of biomarkers may improve the diagnostic accuracy and this might prevent unnecessary further strategies, which will reduce high-cost in health care systems. Furthermore, the investigator hopse for better patient selection in order to avoid unnecessary examinations in the future.