Acute mesenteric ischemia after heart surgery.

INTRODUCTION: Acute mesenteric ischemia (AMI) is a rare but very severe complication of heart surgery, due especially to the delay in setting the correct diagnosis and choosing the appropriate treatment. There are 4 types, but the most frequent is nonocclusive mesenteric ischemia (NOMI). The main mechanism is represented by great decrease or maldistribution of the splenic blood flow, with negative impact on the integrity of the intestinal mucosa, bacterial translocation and multiorganic failure. MATERIAL AND METHOD: We present a retrospective study conducted on patients who underwent open heart surgery with cardiopulmonary bypass with non-pulsatile flow. 4 cases of angiographically confirmed NOMI (non-occlusive mesenteric ischemia) were identified. When, based on clinical examination and laboratory findings, acute mesenteric ischemia was suspicioned, superior mesenteric artery angiography was performed via the femoral artery. RESULTS: The main risk factors were represented by: age over 70 years old, left ventricle ejection fraction (LVEF) 35%,aortic clamping time 100 min., chronic kidney failure,counter-pulsation balloon implant, inotropic medication use,like levosimendan, use of blood components 1 unit of erythrocyte mass. Clinical signs were nonspecific. All patients presented hypoventilation, arterial hypotension, oliguria and,from a biological standpoint, metabolic acidosis and leucocytosis. Superior mesenteric artery angiography was the investigation method of choice. Treatment approach was initially medical, followed by resection of the intestine.Mortality was 100%. CONCLUSIONS: Acute mesenteric ischemia is a rare but very severe complication in cardiac surgery. It is primordial that the main risk factors be known, and in case of diagnosis suspicion, that it be set as early as possible, along with immediate initiation of an appropriate course of treatment.

Restenosis in the coronary stent is an argument for the surgical myocardial revascularization.

BACKGROUND: This study will evaluate the difference between the frequency of restenosis in myocardial revascularization procedures by stents and CABG by coronarographic control after clinical criteria (angina). METHODS AND RESULTS: Out of the total of 6564 coronarographies performed (1999-2002) for diagnosis purposes, 3110 patients (44.8%) underwent myocardial revascularization procedures, PCI or CABG. PCI was performed in 981 patients (31%) and CABG in 1148 patients (37.3%). At the same time, we performed in our units 2067 surgical procedures, out of which 1148 (55%) revascularizations by CABG. The angiographic control for patients with myocardial revascularization by stent (55 patients) or CABG (50 patients) was performed by clinical criteria (angina reappears) on 105 patients. The restenosis we found in 47 patients (74.5%) treated by stent revascularization and in 29 patients from CABG procedures. In our study restenosis rate was 4.8% in patients with PCI and 2.5% in patients with CABG. CONCLUSIONS: Both surgical (CABG) and percutaneous coronary artery revascularization (PCI) have proved to be extremely effective in the treatment of patients with multivessel coronary disease. In our study restenosis rate was smaller in the patients with CABG than in the PCI group, taking into account the fact that we did not use drug eluting stent (DES) on a large scale. Results from the series of randomized trials (SOS, SIRIUS, ERACI, ARTS, BARI, etc.) have shown that the restenosis phenomenon is an apparent advantage in patients with DES. Restenosis prevention is a complex phenomenon (inflammation, procoagulation, cellular migration, etc.) and DES appearance opens a new era in PCI.

Long-term persistence, after eye-removal, of unmyelinated fibres in the frog visual pathway.

Long-term fibre degeneration was studied in the optic nerve, and the optic tectum in Rana esculenta using the cobalt filling technique. Myelinated retinal fibres disappeared within 26 days. A number of unmyelinated axons, however, persisted during the experimental period (91 days after eye removal). It was concluded that myelinated fibres degenerate considerably faster than unmyelinated ones in the frog visual system.