Clinical characteristics and role of early cardiac magnetic resonance imaging in patients with suspected ST-elevation myocardial infarction and normal coronary arteries

Abstract

A variety of conditions other than acute myocardial infarction may cause ST-elevation. Our objective was to evaluate the impact of cardiac magnetic resonance (CMR) on differential diagnosis from a prospective series of patients with suspected ST-elevation myocardial infarction (STEMI) and completely normal coronary arteries. Among 1,145 patients with suspected STEMI, 49 patients had completely normal coronary arteries and entered a prospective registry. CMR was done within 24 h, if possible, and included function analyses, T2-weighted imaging (T2 ratio), T1-weighted imaging before and after gadolineum administration (global relative enhancement; gRE), and late gadolineum enhancement (LGE). All patients were asked for a follow-up CMR after approximately 3 months. The incidence of patients with suspected STEMI and normal coronary arteries was 4.3% and mean age was 45 ± 14 years (STEMI group 64 ± 13 years; P < 0.001). 55% had a recent history of infection. Cardiac biomarkers showed a moderate elevation on admission. There was a significant change from baseline to follow-up for LV end-diastolic volumes (EDV) (P < 0.001), LV mass (P < 0.05), mean T2 ratio (P < 0.05), and LGE volume (P < 0.05). Major diagnostic groups were myocarditis (29%), pericarditis (27%), and takotsubo cardiomyopathy (10%). 18% were regarded as non-diagnostic. The study showed an incidence of 4.3% of patients with suspected STEMI and completely normal coronary arteries. Early CMR was valuable in the evaluation of the differential diagnoses and to exclude myocardial abnormalities in patients with uncertain aetiology. Further studies are needed for the assessment of long-term outcome.

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

“…However, despite an increasing interest, there have been few studies of MINCA, hence the prevalence remains uncertain. It was recently reported that approximately 4% of all patients with suspected myocardial infarction may have angiographically normal coronary arteries [1], whereas we have reported an incidence of 7% [2]. Because myocarditis may mimic myocardial infarction, it is essential to exclude this condition in patients with MINCA.…”

Cardiac MR enables diagnosis in 90% of patients with acute chest pain, elevated biomarkers and unobstructed coronary arteries

“…9 However, increasing evidence suggests that CMR may provide incremental diagnostic value in these patients. [10][11][12][13] We have adopted CMR in the diagnostic work-up of patients with suspected ACS.…”

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.…”

“…13 Advanced imaging modalities, including intravascular imaging and cardiac magnetic resonance imaging (CMR), may help to characterize MI etiology in these patients. [14][15][16][17][18][19] Microvascular coronary disease is a known cause of chest pain with nonobstructive CAD. 20 Abnormal coronary flow reserve is a predictor of adverse outcomes, including death, in stable patients with nonobstructive CAD.…”