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Introduction: Transcatheter aortic valve implantation (TAVI) technique represents a real revolution in the field of interventional cardiology and medicine, in particular for the treatment of severe aortic valve stenosis in elderly patients or in patients when the periprocedural risk for the traditional surgical option is considered too high, as an alternative to the traditional aortic valve replacement. Although experience on the valves of the last generation is still limited in terms of time, the data currently available are definitely moving in the direction of a minimum hospital mortality (1%) as well as a drastic reduction in the incidence of complications when compared to the devices of the previous generation. Finally, the evolution of specified materials of the newest generation have greatly enhanced safety and efficacy of TAVI procedures in the last years. In order to ensure the selection of the most appropriate valve and the success of the procedure, the role of cardiac imaging (computed tomography scan evaluation and angiography) is crucial. These examinations require the use of contrast medium in patients suffering from renal dysfunction at the baseline. The need for fluoroscopy and angiography using contrast agents to aid positioning of the valve may lead to contrast-induced nephropathy (CIN) as one form or one etiology of acute kidney injury (AKI), which is associated with increased morbidity and mortality. The aim of our study is to investigate the accuracy of intravascular ultrasound (IVUS-a technique which does not need contrast) for the assessment of native valve measures in patients undergoing TAVI by comparing values obtained with IVUS to those ones previously obtained in the same patients with computed tomography (CT) scans., Material and Methods: We enrolled 25 consecutive patients (10 males, average age 81.3±5,1 years) who underwent TAVI with femoral access in our Cardiac Surgery Cath-Lab (University of Bari) from January to October 2015 (Logistic EuroSCORE 21.6±15.4%; STS score mortality 20.9±14.9%). Each patient scheduled for TAVI underwent coronary angiography and high resolution angio-CT in order to obtain a complete evaluation (diameters, perimeters, and areas at annulus level, -3mm level, +15mm level, height of coronary ostia, shape, and conformation of left ventricle outflow tract, conformation, and calcifications of aortic and ileo-femoral axis) to choose the most suitable prosthetic aortic valve for each patient. In all patients, during the procedure (before the prosthetic valve implantation), we executed a manual IVUS pullback (from left ventricle outflow tract to ascending aorta) by using a 7F IVUS probe (Volcano Corporation, San Diego, CA). On the recorded IVUS pullback, a second operator (who did not know the values obtained by CT measurements) identified the aortic annulus and, at this level, measured: minimum and maximum diameter; perimeter; derived perimeter, and area. The t-student test has been used to compare the averages of these IVUS values to the CT ones. A p value< 0.05 was considered as statistically significant., Results: Independently from the kind and size of implanted prosthetic valve, no statistical differences were found when the averages of all considered parameters (obtained both with CT and IVUS) were compared. The following are the results obtained: minimum diameter (CT: 19,62mm±1,10 vs. IVUS: 19,55mm±1,40; p=0.41); maximum diameter (CT: 24,73mm±2,42 vs. IVUS: 25,9mm±1,80; p=0.08); perimeter (CT: 72,05mm±4,36 vs. IVUS: 73,32mm±6,09; p=0.164); derived perimeter (CT: 22,94mm±1,40 vs. IVUS: 23,32mm ± 1,95; p=0,198); and area (CT: 3,99cm2 ±0,97 vs. IVUS: 4,06 cm2 ± 0,47; p=0,073) (Figs. 1-3)., Conclusions: These preliminary data suggest accurate IVUS measures when compared to CT in the evaluation of valve parameters considered (minimum and maximum diameters, area, perimeter, and derived perimeter at the annulus level). In order to confirm these findings and to give them statistical significance, it will be necessary to increase the sample size.

The stent graft is a noncompliant system inserted in a semi-compliant structure. This generates a mismatch. The media also shows a composite movement and is oriented 45° resulting in an arterial spiral movement that contributes to maintaining the clockwise orientation of laminar flow with an 80° deflection. Our multilayer stent is constituted by a single Nitinol thread, worked on 3 surfaces in order to realize a proper exoskeleton that reproduces the architecture of the tunica media, in particular its flexo-torsional forces, thus restoring the energy transmission and the match between the wall and the blood flow. A first in vivo implantation was performed by using an experimental pig model in our veterinary department. The pig underwent general anesthesia and the right femoral artery was surgically exposed in order to accommodate a 12F long introducer sheath. Under fluoroscopy three multilayer stents were consecutively implanted from the aortic isthmus to the iliac bifurcation in an overlap fashion. All the intercostal artery and visceral branches were covered by the overlapped stents. The final control angiography revealed an optimal sealing of the implanted stent with an evident flexotorsional oscillatory movement, which follows the conical architecture of the thoracic aorta and the complete patency of all the branches that arise from the aorta. After two months, the multilayer showed a normal endothelialization process with an optimal adhesion to the aortic wall both proximally and distally without provoking any inflammatory response or thickness wall alterations. The perfect and homogenous endothelialization preserved the patency of all the collateral branches arising from the treated aorta, in particular all the intercostal arteries, celiac trunk, and renal arteries. The disease of the aorta essentially concerns the tunica media as it causes disruption of the media components. This exoskeleton works like a neo-tunica media, is perfectly endothelialized, and seems to optimally transmit the flexotorsional forces, restoring the match between wall and flow that represents the primary condition for laminar flow and branch perfusion.

Aortic injury from sudden deceleration is the most common traumatic condition of the thoracic aorta encountered clinically. Open surgical repair is still associated today with a high-risk setting. Recently, stent-graft treatment is emerging as an alternative to conventional surgery due to its less traumatic nature in patients affected by traumatic aortic lesions, especially in concomitance with multiple associated lesions. From March 1999 to June 2009, 57 patients admitted with a diagnosis of acute and chronic aortic lesions underwent endovascular repair. In 38 cases, traumatic aortic rupture was detected in the acute phase and associated lesions were present at various grade in all patients, whereas in 19 cases aortic injury was identified in the chronic phase. The endovascular treatment was successful in all cases affected both by acute and chronic aortic injury. None of the patients died during the follow-up, as well as no cases of perigraft leakage have been detected so far. Endovascular repair represents the first choice of treatment in patients with traumatic aortic lesions. Indeed, the severity of co-existing lesions could be adversely affected by conventional surgical treatment, also with consideration of its high morbidity rate due to thoracotomy.

The The aim of our study is to investigate the molecular mechanisms of diabetic cardiomyopathy through the identification of remarkable genes for the myocardial function that are expressed differently between diabetic and normal subjects. Moreover, we intend to characterize both in human myocardial tissue and in the related cardiac progenitor cells the pattern of gene expression and the levels of expression and protein activation of molecular effectors involved in the regulation of the myocardial function and differentiation to clarify whether in specific human pathological conditions (type 2 diabetes mellitus, cardiac failure, coronary artery disease) specific alterations of the aforementioned factors could take place. Thirty-five patients scheduled for coronary artery bypass grafting (CABG) or for aortic or mitral valve replacement were recruited into the study. There were 13 men and 22 women with a mean age of 64.8 +/- 13.4 years. A list of anamnestic, anthropometric, clinical, and instrumental data required for an optimal phenotypical characterization of the patients is reported. The small cardiac biopsy specimens were placed in the nourishing buffer, in a sterile tube provided the day of the procedure, to maintain the stability of the sample for several hours at room temperature. The cells were isolated by a dedicated protocol and then cultured in vitro. The sample was processed for total RNA extraction and levels of gene expression and protein activation of molecular effectors involved in the regulation of function and differentiation of human myocardium was analyzed. In particular, cardiac genes that modulate the oxidative stress response or the stress induced by pro-inflammatory cytokines (p66Shc, SOCS-1, SOCS-3) were analyzed. From a small sample of myocardium cardiac stem cells and cardiomyoblasts were also isolated and characterized. These cells showed a considerable proliferative capacity due to the fact that they demonstrate stability up to the eleventh passage. Analysis of gene expression in a subgroup of subjects showed the trend of a decrease in levels of expression of cardiac-specific transcription genes and oxidative stress-related proteins in tissues of diabetic patients compared with controls subjects. This trend is not confirmed in isolated cells. As for the coronary artery disease, diabetic cardiomyopathy could be associated with a reduction of the cardiac stem and progenitor cells pool. The expansion of the cardiac resident cells pool could be associated with a preservation of cardiac performance, suggesting that a preserved stamina compartment can counteract the impact of diabetes on the myocardium.