Early detection of doxorubicin myocardial injury by ultrasonic tissue characterization in an experimental animal model.

UNLABELLED: In the clinical setting, the early detection of myocardial injury induced by doxorubicin (DXR) is still considered a challenge. To assess whether ultrasonic tissue characterization (UTC) can identify early DXR-related myocardial lesions and their correlation with collagen myocardial percentages, we studied 60 rats at basal status and prospectively after 2 mg/Kg/week DXR endovenous infusion. Echocardiographic examinations were conducted at baseline and at 8, 10, 12, 14 and 16 mg/Kg DXR cumulative dose. The left ventricle ejection fraction (LVEF), shortening fraction (SF), and the UTC indices: corrected coefficient of integrated backscatter (IBS) (tissue IBS intensity/ phantom IBS intensity) (CC-IBS) and the cyclic variation magnitude of this intensity curve (MCV) were measured. The variation of each parameter of study through DXR dose was expressed by the average and standard error at specific DXR dosages and those at baseline. The collagen percent (%) was calculated in six control group animals and 24 DXR group animals. CC-IBS increased (1.29±0.27 x 1.1±0.26-basal; p=0.005) and MCV decreased (9.1± 2.8 x 11.02±2.6-basal; p=0.006) from 8 mg/Kg to 16 mg/Kg DXR. LVEF presented only a slight but significant decrease (80.4±6.9% x 85.3±6.9%-basal, p=0.005) from 8 mg/Kg to 16 mg/Kg DXR. CC-IBS was 72.2% sensitive and 83.3% specific to detect collagen deposition of 4.24% (AUC=0.76). LVEF was not accurate to detect initial collagen deposition (AUC=0.54). IN CONCLUSION: UTC was able to early identify the DXR myocardial lesion when compared to LVEF, showing good accuracy to detect the initial collagen deposition in this experimental animal model.

Cardiogenic shock post acute myocardial infarction associated with a non reperfusion coronary artery phenomenon / Choque cardiogênico após infarto agudo do miocárdio associado ao fenômeno de não reperfusão da artéria coronária

Cardiogenic shock is a state of systemic tissue hypoperfusion resulting from a primary cardiac dysfunction. When it occurs simultaneously to a non reperfusion coronary artery phenomenon, prognosis worsens and mortality chances increases. This paper reports the case of a patient presenting cardiogenic shock after acute myocardial infarction - AMI concurrently with no-reflow phenomenon. It is a clinical case, cares and main aspects in treatment for simultaneous cardiogenic shock and no-reflow phenomenon are discussed, pointing out the relevance of early detection of these two clinical situations as to correct their deriving dysfunctions and ensure the best possible prognosis to the patient.

O choque cardiogênico é um estado de hipoperfusão sistêmica do tecido resultante de uma disfunção cardíaca primária. Quando ocorre simultaneamente a este fenômeno a não reperfusão da artéria coronária, o prognóstico piora e as chances de mortalidade aumentam. Este artigo relata o caso de um paciente que apresentou choque cardiogênico após infarto agudo do miocárdio - IAM e simultaneamente com fenômeno sem refluxo. Trata-se de um caso clínico, onde são abordados os principais aspectos no tratamento do choque cardiogênico simultâneo e do fenômeno de não refluxo, destacando a relevância da detecção precoce dessas duas situações clínicas para corrigir suas disfunções derivadas e assegurar o melhor prognóstico possível para o paciente.