Cardiac myxoma: diagnostic approach, surgical treatment and follow-up. A twenty years experience.

At the University Department of Cardiovascular Surgery in Zagreb, Croatia, we treated 81 patients with primary intracardiac myxoma, in a period from January 1975 to December 1994. There were 55 female and 26 male pts, in age from 1 month to 80 years, mean 46+/-15 years. Clinical manifestations varied from no symptoms and very poor or no clinical signs to various manifestations of chronic or acute congestive heart failure, syncope and arrhythmias with or without systemic findings such as high erythrocyte sedimentation rate, anaemia, leucocytosis, elevated gamma globulin, thrombocytopenia or low grade fever, as well as cerebrovascular accidents due to tumour embolization. Cardiac symptoms were predominant in 54 pts (66.6%) and cerebrovascular in 20 pts (24.7%). Seven pts (8.6%) were symptomless and discovered accidentally, mostly regarding on an unexplained heart murmur. In almost all the patients preoperative diagnosis of intracardiac myxoma was sufficiently established by echocardiography. The tumour was located in the left atrium in 62 pts (76.5%) and in the right atrium in 19 pts (23.5%). Delay from the onset of symptoms to the diagnosis was 6 months in average (range 10 days to 25 months). The average waiting for the operation was 9 days (range from 1 to 60 days). The echocardiographic diagnosis was confirmed during intraoperative examination followed by histological analysis. All pts underwent excision of myxoma using cardiopulmonary bypass with core and topical hypothermia and cold crystaloid cardioplegia. According to the additional preoperative and intraoperative findings, in 6 pts sinchronous mitral valve reconstruction, in 3 pts artificial mitral valve implantation and in 2 pts atrial wall reconstruction was performed. There was no perioperative mortality. After the operation, we could not evaluate all the patients long enough, mostly because of some paramedical circumstancies, such as war, migrations, etc. Twenty two pts undevent evaluation for at least 5 years after the operation. Among them there was no evidence of the tumour recurrence, 15 pts were asymptomatic and 7 had NYHA II class symptoms. For 17 pts with a left atrial myxoma preoperative and postoperative echocardiographic data were available for comparison, showing a significant reduction of the left atrial diameter (p<0.001) during the postoperative follow-up. Our data, presenting one of the biggest reports concerning cardiac myxomas, showed a broad spectrum of their clinical presentation, importance of echocardiography in diagnosing and postoperative follow-up and efficacy of a proper surgical intervention as a definite, curative therapy since there were no deaths and no significant cardiac dysfunction neither tumour reccurrence as well.

Wound infection after median sternotomy during the war in Croatia.

From 1990 to 1994 at Clinical Hospital Center, Zagreb, 1904 median sternotomies were performed for cardiac operations. Patients shared the same intensive care unit (ICU) with the wounded persons, admitted to the hospital from battlefield. Infection developed in 124 patients, an incidence of 6.51%. Methicillin resistant Staphylococcus aureus (MRSA) was isolated from 90, methicillin resistant Staphylococcus epidermidis (MRSE) from 19, and gram negative bacilli (GNB) from 56 patients, Pseudomonas aeruginosa in 2, and Clostridium pneumoniae in 1 case. Ninety-six patients (5.04%) developed superficial localized infection of subcutaneous tissues and they were treated with frequent dressing changes with antibiotic-soaked gauze in combination with systemic antibiotics. Twenty-eight patients (1.47%) developed mediastinitis and sternal dehiscence. They were treated by operative debridement followed by reclosure of the sternum with continuous antibiotic irrigation. We obtained satisfactory results with our method of closure of sternum which is a modification of Robicsek's technique. Nine of them required further operation. In seven cases we performed muscle flaps and in two omentoplasty. One hundred and twenty patients were discharged in satisfactory condition. The uncontrolled mediastinal sepsis caused death in 4 patients. Higher infection rate after median sternotomy during 1991 and 1992 could be possibly explained with the war circumstances in Croatia, and especially with MRSA strain becoming endemic in surgical ICU.

Molecular architecture of the lens fiber cell basal membrane complex.

Lens fiber cells are transparent, highly elongated, epithelial cells. Because of their unusual length these cells represent a novel model system to investigate aspects of epithelial cell polarity. In this study, we examined the fiber cell basal membrane complex (BMC). The BMC anchors fiber cells to the lens capsule and facilitates their migration across the capsule. Confocal microscopy revealed that bundled actin filaments converge beneath the center of each BMC and insert into the lateral membrane at points enriched in N-cadherin. Two other contractile proteins, caldesmon and myosin, were enriched in the BMC, co-localizing with f-actin bundles. The actin/N-cadherin complex formed a hexagonal lattice, cradling the posterior face of the lens. Removal of the capsule caused the tips of the fiber cells to break off, remaining attached to the stripped capsule. This provided a method for assaying cell adhesion and purifying BMC components. Fiber cell adhesion required Mg2+ and/or Ca2+ and was disrupted by incubation with beta1 integrin antibody. BMC proteins were compared with samples from the neighboring lateral membrane. Although some components were common to both samples, others were unique to the BMC. Furthermore, some lateral membrane proteins, most notably lens major intrinsic protein (MIP), were excluded from the BMC. Western blotting of BMC preparations identified several structural proteins originally found in focal adhesions and two kinases, FAK and MLCK, previously undescribed in the lens. These data suggest that the BMC constitutes a distinct membrane domain in the lens. The structural organization of the BMC suggests a role in shaping the posterior lens face and hence the refractive properties of the eye.