Contusion myocardiqueMyocardial contusion.

Within the framework of blunt cardiac injury, myocardial contusion (MC) is a specific pathological entity. In clinical practice, blunt chest trauma and multiple trauma are the two circumstances when the diagnosis of MC has to be suggested. The ECG abnormalities concerning MC are considered to be early and transient. The poor sensitivity and predictive values of troponins I and T (when ECG and/or echocardiography diagnostic criterions are considered) do not make these markers relevant for improving the biological diagnosis of MC. Echocardiography should be performed in case of ECG abnormalities, increase of enzymatic markers or hemodynamic instability. It allows one to perform the diagnosis of MC in case of abnormalities of the segmental ventricular wall kinetics, which progressively returns to normal. Only the pathological analysis could allow establishing a final diagnosis. In the initial phase of the management, the probability of the diagnosis might be performed with some arguments including clinical, ECG, biological and echocardiographic data. Later, the lability of both the ECG and the echocardiographic data is another criterion for making a final diagnosis of MC. Myocardial contusion has direct arrhythmogenic effects and the seriousness of arrhythmia increases with the level of contusion kinetic energy. The mechanism of arrhythmia is mainly based on the reentrant circuit around a fixed obstacle. There is no paraclinical parameter to reliably discriminate patients at risk of arrhythmia, especially for otherwise asymptomatic patients. In an animal model, lignocaine at low therapeutic concentrations is able to restore contractility after contusion. These results warrant further confirmations for clinical practice.