Cardiac magnetic resonance imaging for the diagnosis of patients presenting with chest pain, raised troponin, and unobstructed coronary arteries

Abstract

To evaluate the incremental diagnostic and prognostic value of cardiac magnetic resonance (CMR) in patients with chest pain, raised troponin and unobstructed coronary arteries, and to compare subsequent event rates between diagnostic groups. 130 patients (mean age: 54 ± 17) presenting with troponin-positive acute chest pain and unobstructed coronary arteries were included. All patients were managed according to European Society of Cardiology guidelines, including echocardiography, and had CMR within 6.2 ± 5.3 days of presentation. During follow-up, major adverse cardiovascular events (MACE) were recorded. CMR provided a diagnosis in 100 of 130 patients (76.9%), with the remaining 30 (23.1%) having a normal examination. CMR diagnosed 37 (28.5%) acute myocardial infarctions, 34 (26.1%) myocarditis, 28 (21.5%) apical ballooning syndromes and 1 (0.8%) hypertrophic cardiomyopathy. When a single diagnosis was suspected by the referring physician, CMR validated this diagnosis in 32 patients (76.2%). CMR provided a formal diagnosis in 61 patients (69.3%) in which the clinical diagnosis was uncertain between at least two possibilities. CMR corrected a wrong diagnosis in 10 patients (7.7%). CMR-suggested diagnosis led to a modification of therapy in 42 patients (32.3%). Median follow-up was 34 months (interquartile range 24-49) in 124 patients. Sixteen patients (12.9%) experienced MACE. MACE rate was not different between patients with a conclusive CMR and normal CMR. In patients with acute troponin-positive chest pain and unobstructed coronary arteries, early CMR has important diagnostic and therapeutic implications. However its association with occurrence of MACE during mid term follow-up was not obvious.

Myocardial infarction with normal coronary arteries is common and associated with normal findings on cardiovascular magnetic resonance imaging: results from the Stockholm Myocardial Infarction with Normal Coronaries study

“…Furthermore, an initial diagnosis of acute coronary syndrome was changed in two of three patients. This is in accordance with two previous studies [3,12] in which the initial diagnosis or therapy was modified after CMR imaging in 65% and 32% of cases, respectively. Thus, it seems appropriate to consider CMR imaging as a standard investigational tool in patients with MINCA.…”

“…In the previous studies by Assomull et al [3] and Laraudogoitia Zaldumbide et al [5], younger patients were included resulting in a lower mean age (44-48 years) and a higher prevalence of myocarditis. Gerbaud et al [12] on the other hand included 130 patients with a mean age of 54 years, 26% of whom had myocarditis, supporting the validity of our results. Second, the majority of patients with MINCA (64%) from the Stockholm metropolitan area over a 4-year period were included in the present study, which was therefore more representative of all patients with this condition than previous studies.…”

“…There are two possible reasons for this. First, our study population was older (mean age 57 years) in comparison with previous studies and it has been shown that myocarditis is more common in younger cohorts [3,5,12]. The age range in this study, 35-70 years, was chosen to minimize the number of patients with myocarditis and to ensure a high proportion of patients undergoing coronary angiography.…”

“…Our finding of a high incidence of MINCA is even more notable as patients with secondary myocardial infarction caused by atrial fibrillation or supraventricular tachycardia where excluded. In previous studies, these patients were included [3,12] or not adequately described [5]. Atrial fibrillation or supraventricular tachycardia with a high ventricular rate is a known cause of elevated troponin levels and chest pain and might therefore dilute the number of patients in these studies.…”

Stress Cardiac MRI in Women With Myocardial Infarction and Nonobstructive Coronary Artery Disease

“…[20][21][22][27][28][29] Prior studies using CMR perfusion imaging in patients with acute coronary syndrome and nonobstructive CAD did not include stress testing. [16][17][18][19]30,31 Adenosine stress perfusion CMR is highly sensitive, specific, and reproducible for identification of obstructive CAD and has been reported to be superior to other stress imaging methods for this purpose. [32][33][34][35][36][37][38] In the setting of stable, nonobstructive CAD, patients with proven microvascular disease based on invasive coronary reactivity testing had lower MPRI as compared with healthy controls.…”