[Cardiac magnetic resonance imaging and coronary optical coherence tomography : Acquisition techniques, interpretation and integration in diagnostic algorithms for MINOCA]. / Imagerie par résonance magnétique et imagerie endocoronaire par tomographie par cohérence optique : acquisition, interprétation et intégration dans le diagnostic étiologique des MINOCA.

MINOCA is a heterogeneous entity with many possible etiologies that need to be clarified to optimize therapeutic interventions. Common causes include plaque disruption, plaque erosion, spontaneous coronary artery dissection, coronary artery spasm, coronary thromboembolism. Most of the time, coronary angiography is inadequate to obtain the proper identification of these underlying pathophysiological mechanisms. Within this context, myocardial tissue characterization with magnetic resonance imaging is key investigation to assess and locate recent myocardial infarctions and to exclude differential diagnostics such as myocarditis or takotsubo cardiomyopathy. In addition, optical coherence tomography is a powerful tool to visualize coronary intraluminal and superficial coronary artery structures in detail including the detection of plaque disruption signs, thrombus or dissections. The use of appropriate diagnostic algorithms combining both OCT and CMR seems to provide a clear substrate or diagnosis to many of the cases. This narrative review aims to expose both imaging modalities focusing on their contributions in the setting of MINOCA.

A high prevalence of arterial hypertension in patients with mitochondrial diseases.

The prevalence of arterial hypertension in mitochondrial diseases remains unknown. Between January 2000 and May 2014, we retrospectively included patients with genetically proven mitochondrial diseases. We recorded clinical, genetic and cardiac exploration data, including the measure of arterial pressure. Among the 260 patients included in the study (mean age = 44 ± 15 years, women = 158), 108 (41.5%) presented with arterial hypertension. The prevalence of hypertension by sex and age was higher than that observed in the general population for all groups. The prevalence of hypertension was significantly higher in patients with MELAS (mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes) mutations (66%) and MERRF (myoclonus, epilepsy, ataxia with ragged ref fibres) mutations (61%). In patients with MELAS mutation, the presence of hypertension was significantly associated with age and mutation rate in the blood (odds ratio = 1.12; P = .02) in multivariate analysis. The prevalence of hypertension was more important in patients having a mitochondrial disease. The increased risk was more important in patient with MELAS or MERRF and depended on the rate of heteroplasmy.