Point-of-care detection of myocardial injury, a pre-clinical study

Evaluation of myocardial function is critical in severe inflammations as myocarditis, COVID-19 and sepsis, since it can lead to organ failure and death. Point-of-care detection of myocardial injury may improve the treatment of these critically ill patients. The study aimed to develop point of care technology for assessing the systolic and diastolic cardiac functions in animal model of systemic inflammation. Ultrasound and ventricular pressure were continuously recorded in Langendorff perfused isolated adult rat hearts. A computer controlled system controlled the ventricle loading conditions. The preload of both ventricles swung in a sinusoidal manner between target values of 2 and 22 mmHg. Collagenase (MMP8) was added to the Krebs-Henseleit solution following baseline recordings, to emulate the release of MMPs from activated leukocytes and macrophages. Collagenase perfusion led to gradual decline in peak systolic pressure and decrease in the end-diastolic volume (EDV), that were associated with concentric myocardial wall thickening. Extracellular matrix degradation by collagenases caused sever diastolic dysfunction with overt shift of the end-diastolic volume toward lower volumes, without significant changes in the epicardial diameter. Early detection of these signs may assist in assessing the severity of the myocardial injury and prompt the adequate treatment.