Pilot Study Evaluating Somatostatin Receptor's PET Imaging to Detect Inflammatory Phases of Myocarditis (DOTAMIR)

Pilot Study Evaluating Somatostatin Receptor's PET Imaging to Detect Inflammatory Phases of Myocarditis

Monocentric Interventionnal Pilot Study Pilot Study Evaluating Somatostatin Receptor's PET Imaging to Detect Inflammatory Phases of Myocarditis

Infectious myocarditis are frequent, most of the time viral and can evolve to cardiac insufficiency. The diagnosis is difficult because they can mime an acute coronary syndrome. Approximately 10 % of patients with acute infarction suspected, have a normal angiography, and half of them has in fact a myocarditis, as showed studies of cardiac MRI among which some realized in our department . However, anomalies observed in MRI are not specific and it is necessary to use multiple criterions. A new radiopharmaceutical, the 68Ga-DOTATOC, specific of somatostatin's receptors which are over expressed by the inflammatory cells, has recently showed the capacity to identify myocarditis, but only in a small group of 6 patients. The investigators make assumptions: this radiopharmaceutical is enough sensitive to detect most of the acute inflammatory myocarditis which are identified by the MRI and it could maybe allow to identify myocarditis with a persistent subacute or chronic inflammation, which are difficult to identify with cardiac MRI, and it would be a new information able to guide the medical decision. Primary objectif: to determine if PET with 68Ga-DOTATOC is enough sensitive to identify myocarditis in acute inflammatory phase by hospitalized patients with suspected acute infarction and with normal angiography and who have a high probability of myocarditis identified by MRI. Disease prevalence will be close to 100 % at baseline Secondary objectives: 1. Estimate the frequency of inflammatory forms (subacute or chronicle), with a 68Ga-DOTATOC PET at 3 to 5 months from baseline, when classic signs of acute inflammatory generally disappeared (CRP, Troponin-I, myocardial oedema in MRI). 2. Analyze the concordance of the results of 68Ga-DOTATOC TEP by two readers

All included patients wil receive 68Ga-dotatoc-PET/CT suspected acute myocarditis in first and an other 68Ga-dotatoc-PET/CT 6 months later

DOTATOC is a tracer of high affinity for the type 2 somatostatin receptors and is used for imaging of tumours which are expressing them, including endocrine tumours

DOTATOC is a tracer of high affinity for the type 2 somatostatin receptors and is used for imaging of tumours which are expressing them, including endocrine tumours

blood tests will be carried out during the control visit to ensure that biological parameters are normalized

Presence of a significant myocardial retention of 68Ga-DOTATOC during initial staging. Sensibility calculation

The criterion of positivity will be that of a visually detectable and quantitatively significant area of myocardial uptake, which will be defined by a measurement of the Standardized Uptake Value (SUV) at least 30% higher than that of the blood signal obtained at the center of the left ventricular cavity. This threshold was chosen based on measurements already published in a small pilot study.

a visually detectable and quantitatively significant area of myocardial uptake, which will be defined by a measurement of the Standardized Uptake Value (SUV) at least 30% higher than that of the blood signal obtained at the center of the left ventricular cavity. This threshold was chosen based on measurements already published in a small pilot study. a visually detectable and quantitatively significant area of myocardial uptake, which will be defined by a measurement of the Standardized Uptake Value (SUV) at least 30% higher than that of the blood signal obtained at the center of the left ventricular cavity. This threshold was chosen based on measurements already published in a small pilot study. visually detectable and quantitatively significant area of myocardial uptake, which will be defined by a measurement of the Standardized Uptake Value (SUV) at least 30% higher than that of the blood signal obtained at the center of the left ventricular cavity.

Inclusion Criteria: Adult subjects who have given their written consent to participate in the study. Patients without history of heart disease, hospitalized for acute infarction suspected with positive troponine, normal or subnormal angiography and which have a high probability of acute inflammatory myocardities on the secondarily realized MRI (= 2 criteria of Lake Louise) No contraindication to perform a 68Ga-DOTATOC-PET . Patient belong to a social security scheme. Exclusion Criteria: Patients under guardianship or curatorship. Pregnancy, breastfeeding and woman of childbearing age without effective contraception Impossibility to perform a PET with 68Ga-DOTATOC (patient agitated). Impossibility to schedule PET/CT before the deadline = in 7 days since the beginning of the hospitalization.