[Identification of the ischemic origin of dilated myocardiopathy using positron emission tomography]. / Identificación del origen isquémico de la miocardiopatía dilatada mediante tomografía por emisión de positrones.

INTRODUCTION AND OBJECTIVES: The aim of this study was to differentiate ischemic from nonischemic dilated cardiomyopathy with positron emission tomography. This differentiation is necessary to establish an adequate treatment, and it is often difficult with non-invasive diagnostic procedures. METHODS: Ten patients with an echocardiographic diagnosis of dilated cardiomyopathy who had undergone coronary angiography were selected. The presence or absence of angiographic coronary lesions was used to define the ischemic (n = 6) and the nonischemic group (n = 4). The ejection fraction was depressed in both groups, with no significant differences found. A perfusion study with 13N-ammonium and a metabolic imaging with 18F-florodeoxyglucose were performed on each patient. The images were quantitatively and qualitatively analysed, defining three criteria: accumulation defect (areas with activity under 50% of the maximal radioactivity), degree of heterogeneity, and match of images with both tracers. To determinate the degree of heterogeneity, nine segments on the three standard tomographic planes were studied. Based on the following heterogeneity features: irregular borders, coexisting different degrees of accumulation, and patched accumulation, a score ranging from 0 to 3 points was assigned to these segments. To analyse the radioactivity defects and the matching of studies with both tracers, the accumulation defects or the accumulating surface were outlined on a midventricular level coronal plane. RESULTS: The ischemic group has contrary to the nonischemic one, wider perfusion (0.26 +/- 0.21 vs 0.00) and metabolism defects (0.38 +/- 0.30 vs 0.06 +/- 0.09; p < 0.05). The degree of heterogeneity is significantly higher in the nonischemic group, either in perfusion (14.5 +/- 8.38 vs 2.5 +/- 1.04; p < 0.05) or in metabolism studies (15.5 +/- 3.31 vs 2.33 +/- 1.50; p < 0.005). Assigning wide defects and homogeneous accumulation to ischemic cardiomyopathy, and absence of defects and heterogeneous accumulation to nonischemic cardiomyopathy, the aetiology of the disease was identified in 9 of the 10 cases in the perfusion study and 100% of them with the metabolism imaging. CONCLUSIONS: Positron emission tomography allows to identify the aetiology of dilated cardiomyopathy, either with coronary perfusion or with myocardial glucose metabolism studies. Thus, only one of both PET studies could be used. Ischemic cardiomyopathy is characterised by wide defects and homogeneous radioactivity, and the nonischemic one by the absence of defects and heterogeneous accumulation of the tracer.

[The progression of a postinfarct interventricular communication: an echocardiographic follow-up]. / Progresión de una comunicación interventricular postinfarto: seguimiento ecocardiográfico.

An 80-year-old female patient presented rupture of the interventricular septum as complication of acute anteroseptal myocardial infarction. Serial echocardiographic studies documented progressive increase in size of the apical defect over 16 hours. This observation highlights a potential hazard if surgical repair is deferred to "stabilize" hemodynamically the patient before the intervention.

Myocardial infarction and subtotal obstruction of the anterior descending coronary artery caused by trauma in a football player.

A 26-year-old professional football player had a myocardial infarction when he was practicing his sport. He arrived at the hospital 1 hour later. Angiographic study showed critical stenosis and distal thrombosis in the anterior descending coronary artery. Intracoronary thrombolytic and vasodilator therapy followed by dilatation angioplasty resolved these coronary obstructions. We conclude that several factors contributed to the origin of myocardial infarction in this case including a complicated atheromatous plaque, formation of thrombus and coronary spasm.