Contrast-enhanced adenosine-stress magnetic resonance imaging - Feasibility and practicability of a protocol for detection or exclusion of ischemic heart disease in an outpatient setting

Evaluating myocardial function, assessing ischemic myocardial areas and detecting myocardial viability are necessary diagnostic information for guiding further therapy in patients with angina. The aim of this study was to show feasibility and safety of a compiled contrast- enhanced magnetic resonance imaging (ceMRI) protocol providing the above mentioned diagnostic possibilities and to demonstrate its applicability in daily routine. Consecutive patients with angina were screened on a 1.5 Tesla system. Functional images in short and long axis orientation were acquired for each patient. First-pass kinetics of a gadolinium-based contrast agent (0.1 mmol/kg) were measured after three minutes of stress with adenosine infusion (140 mu g/kg/min). 10 min after a second bolus injection of contrast agent late enhancement (MLE) sequences were acquired for the detection of myocardial necrosis. We enrolled 3174 patients referred for ceMRI for detection or exclusion of ischemic heart disease. One patient experienced a major complication due to hyperventilation followed by grand mal seizure. In 1121 (35.3%) patients minor complications, such as mild chest pain or dyspnea (30%), temporarily and asymptomatic AV block (3%) or nausea (2%) could be observed under adenosine infusion. Hypoperfusion in more than one myocardial segment and affecting more than 1/3 of the myocardial wall diameter could be detected in 1972 (62%) patients. Subendocardial hypoperfusion with limited duration could be shown in 897 (28%) patients. In 305 (10%) patients hypoperfusion could be excluded. MLE could be seen in 532 (17%) patients. This compiled ceMRI protocol is suitable for detection or exclusion of ischemic heart disease in an outpatient routine. We showed feasibility, applicability and safety of our protocol. CeMRI may serve as a useful surrogate for non-invasive diagnostics prior to invasive coronary angiography in many outpatients.