Miroslav Špaček

Endovascular Treatment of Infected Aortic Aneurysms

OBJECTIVE To report on the short- and long-term outcomes of patients with primary infected aortic aneurysm (IAA) treated by stent graft (SG) in two centers. MATERIAL AND METHOD Over a period of 15 years, 32 patients with IAA underwent endovascular treatment. None had undergone previous aortic surgery. The causal relationship was gastrointestinal infection in 9 patients (28%), endovascular diagnostic/therapeutic procedures/resuscitation in 6 (19%), wound infection after previous surgeries in 5 (16%), urinary infection in 4 (13%), urology or gastroenterology procedures in 3 (9%), pancreatitis in 2 (6%), endocarditis in 1 (3%) and phlebitis in 1 (3%) patient. We implanted 11 bifurcated, 10 tubular thoracic, 4 aorto-uni-iliac, 4 tubular abdominal and 1 iliac SG. Two other surgeries were hybrid procedures. RESULTS The etiological agent was identified in 28 (88%) patients. Twenty-six (81%) patients survived the 30-day postoperative period. Sixteen (50%) survived to 1-year follow-up and 13 (40.6%) survived to 3-year follow-up. Three patients have survived for less than 1 year and a further 3 for less than 3 years, so far. Among patients with aneurysms situated in central parts of the thoracic and infrarenal aorta there was a better death/survival ratio than among patients with a proximal or distal aneurysm location. CONCLUSION The implantation of a SG may be an alternative to open surgery in selected groups of patients with primary IAA. Aneurysms of the central part of the thoracic or abdominal aorta have a more favorable prognosis with endovascular treatment.

Immunosuppressive protocols with tacrolimus after cryopreserved aortal allotransplantation in rats

Objectives and design The aim of our study was to simulate in rats all aspects and techniques used in our new clinical program of cryopreserved alloarterial transplantation and investigate the influence of two immunosuppressive protocols with tacrolimus on acute rejection of these allografts. Materials and methods Cryopreserved abdominal aortic grafts were transplanted between Brown-Norway and Lewis rats. Tacrolimus (0.2 mg/kg daily) was administered from day 1 to day 30 (TAC1) or from day 7 to day 30 (TAC7), respectively. No immunosuppressed isogeneic (ISO) and allogeneic (ALO) rats combination served as control. Aortal wall infiltration by immunocompetent cells (MHC II+ cells of recipient origin) was studied on day 30 after transplantation. Flow cytometry was used for the analysis of day 30 sera for the presence of donor specific anti-MHC class I and II antibodies. Results The aortal allografts in both immunosuppressed groups showed regular morphology of aortal wall with no depositions of immunoglobulin G on day 30. The adventitial infiltration of non-immunosuppressed aortal allografts by MHC class II positive cells of recipient origin was significantly higher (ALO 20.7±6.7 cells, P<0.001) compared to both immunosuppressed groups (TAC1 5.9±5.5 cells, TAC7 6.1±5.1 cells). Day 30 sera from the allogeneic non-immunosuppressed animals decreased significantly the binding of fluorescence-labelled MHC class I (46.9±19.4%) and class II (65.8±11.9%) antibody to donors spleen cells compared with day 30 sera from both immunosuppressed groups (TAC1, anti-MHC class I 102.4±4.2%, p < 0.001, anti-MHC class II 102.6±6.0%), (TAC7, anti-MHC class I 79.9±3.3%, p < 0.001, anti-MHC class II 80.9±2.7%). Conclusion Both immunosuppressed protocols with tacrolimus (administration from day 1 or from day 7 following transplantation) were able to suppress acute cell- and antibody-mediated rejection of cryopreserved abdominal aortic allografts processed in accordance with our new standardized clinical protocol.

Structural changes arising from different thawing protocols on cryopreserved human allograft’s aortic valve leaflets

BACKGROUND The aim of our experimental work was to assess the impact and morphological changes that arise during different thawing protocols on human aortic valve (AV) leaflets resected from cryopreserved aortic root allografts (CARAs). OBJECTIVES Two thawing protocols were tested: 1. CARAs were thawed at a room temperature (23°C); 2. CARAs were placed directly into a water bath at a temperature of 37°C. After all the samples were thawed, non-coronary AV leaflets were sampled from each specimen and fixed in a 4% formaldehyde solution before they were sent for morphological analysis. MATERIAL AND METHODS All the samples were washed in distilled water for 5 min and dehydrated in a graded ethanol series (70%, 85%, 95%, and 100%) for 5 min at each level. The tissue samples were then immersed in 100% hexamethyldisilazane (HMDS) for 10 min, and then air-dried in an exhaust hood at room temperature. Processed samples were mounted on stainless steel stubs and coated with gold. Histological analysis was performed with the use of an electron microscope on a scanning mode operating at 25 kV - BS 301. RESULTS Thawing protocol 1 (room temperature at 23°C): 6 (100%) samples showed loss of the endothelial covering of the basal membrane with no damage to the basal lamina. Thawing protocol 2 (water bath at 37°C): 5 (83%) samples showed loss of the endothelial covering of the basal membrane with no damage to the basal lamina. One (17%) sample showed loss of the endothelial covering the basal membrane with significant damage to the basal membrane. CONCLUSIONS Based on our experimental work, we can clearly conclude that cryopreserved AV leaflet allografts show identical structural changes at different rates of thawing.

Cryopreserved human aortic root allografts arterial wall: Structural changes occurring during thawing

Background The aim of our experimental work was to assess morphological changes of arterial wall that arise during different thawing protocols of a cryopreserved human aortic root allograft (CHARA) arterial wall. Methods The experiment was performed on CHARAs. Two thawing protocols were tested: 1, CHARAs were thawed at a room temperature at +23°C; 2, CHARAs were placed directly into a water bath at +37°C. Microscopic samples preparation After fixation, all samples were washed in distilled water for 5 min, and dehydrated in a graded ethanol series (70, 85, 95, and 100%) for 5 min at each level. The tissue samples were then immersed in 100% hexamethyldisilazane for 10 minutes and air dried in an exhaust hood at room temperature. Processed samples were mounted on stainless steel stubs, coated with gold. Results Thawing protocol 1: All 6 (100%) samples showed loss of the endothelium and damage to the subendothelial layers with randomly dispersed circular defects and micro-fractures without smooth muscle cells contractions in the tunica media. Thawing protocol 2: All 6 (100%) samples showed loss of endothelium from the luminal surface, longitudinal corrugations in the direction of blood flow caused by smooth muscle cells contractions in the tunica media with frequent fractures in the subendothelial layer Conclusion All the samples thawed at the room temperature showed smaller structural damage to the CHARA arterial wall with no smooth muscle cell contraction in tunica media when compared to the samples thawed in a water bath.

Iatrogenic post-catheterization radial arteriovenous fistula in 64-old male patient

Background: We are presenting a case report of an iatrogenic left radial post-catheterization arteriovenous fistula. A 64-year-old male patient one year after percutaneous coronary intervention (PCI) with coronary stent implants was admitted with a pulsatile, palpable mass with bruit and intermittent pain in the region of the left radial artery. Finding: Ultrasonography of the left radial artery was performed, confirming a radial arteriovenous fistula (AVF) in the place of PCI. Method: Percutaneous embolization (PE) with thrombin was chosen as a treatment of choice based on the anatomical localization and characteristics of the AVF. The PE treatment was repeated twice with suboptimal post-procedural result. One day after the PE an ultrasonographic check-up was performed, confirming a suboptimal result of PE with a light palpable bruit present in the place of the AVF. Patient was indicated for surgical resection. After the surgical resection, patient was immediately relieved of all accompanying symptoms and was discharged two days after the procedure. Conclusion: The preferred treatment of choice for post-catheterization arteriovenous fistulas is percutaneous embolization. Surgical resection of post-catheterization AVF is used only when all percutaneous treatments fail.

Differential impact on acute kidney injury incidence between on- and off pump coronary artery bypass grafting in octogenarians

INTRODUCTION Acute kidney injury (AKI) following surgical myocardial revascularization is associated with high mortality and morbidity. The aim of this study was to evaluate the risk of acute kidney injury in a population of very old patients following different surgical techniques. PATIENTS AND METHODS A retrospective study of 310 consecutive patients aged 78 to 93 years, mean 80.5±2.2, who underwent surgery at one cardiac surgery centre. Based on the surgical technique used the patients were divided into: Group I. CABG (n=134) - surgical myocardial revascularization using extracorporeal circulation and arterial and venous grafts. Group II. OPCABG (n=55) - surgical revascularization without extracorporeal circulation but using arterial and venous grafts. Group III. NOTOUCH (n=121) - no handling with the ascending aorta was performed at all. RESULTS A statistically insignificant renoprotective trend was found in patients who underwent surgery without extracorporeal circulation regardless of technique. Comparing groups II and III vs. group I, a significantly poorer renal functioning (median difference in creatinine was 10.0 (32.9) vs 17.5 (35.0), P=0.05) was shown for patients in group I. CONCLUSION Surgical myocardial revascularization without extracorporeal circulation in very old patients is safe. The results of this study show a renoprotective trend.

Surgical Extirpation of Glomus Tumor from Rare Localization on the Upper Extremity

Objective. To report on a very rare case of a glomus tumor manifested on the upper arm in a healthy young male patient. Case Presentation and Intervention. A 22-year-old male patient presented with bluish multifocal venous malformation on the left upper arm and was admitted for venous malformation excision. Pain, discomfort, and upper arm paraesthesia had been present for almost 6 years. Ultrasonography revealed septet tumor without blood flow in the subcutaneous region of anterior aspect of the upper arm. A multifocal venous malformation approximately 5–10 mm in diameter was excised. Histological examination showed dilated vascular area with proliferated glomus cells with round nucleus in the wall of dilated vascular structures. Based on histological examination, the final diagnosis was made as “glomangioma.” Conclusion. Histological examination is the only method that can establish final diagnosis. Currently, the only available treatment for this type of tumor is surgical excision.