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Gianantonio Nappi

Publications and source records attributed to Gianantonio Nappi.

14 recordsLinked to original sources

Biotechnological traps for the reduction of inflammation due to cardiopulmonary bypass operations.

Cardiopulmonary bypass induces a systemic inflammatory response (SIR), characterized by the activation of cellular and humoral elements, with concomitant release of neutrophil elastase and matrix-metallo proteinases. In the present study, the protease release during extracorporeal circulation in 28 patients undergoing cardiac surgical operations was monitored using casein zymography. A peak in protease activity was found in all patients at the end of cardiopulmonary bypass. Plasma samples of patients were allowed to interact with different traps obtained by immobilizing different protease inhibitors on specific carriers. alpha1-Antitrypsin, Bovine Pancreatic Trypsin Inhibitor, Elastatinal or Leupeptin were used as inhibitors and were covalently immobilized by diazotization or by condensation. A reduction in the proteolytic activity of the plasma samples was observed after interaction with the different traps. The most efficient traps, i.e. the ones displaying greatest power to inhibit protease activity, were those obtained by immobilizing Bovine Pancreatic Trypsin Inhibitor and Leupeptin. The biocompatibility of traps was also tested. Results show that protease activity in blood can be decreased by our protease traps.

Animals↗

Ascending aorta dilatation in aortic valve disease: morphological analysis of medial changes.

We investigated whether and how the severity of medial degeneration lesions varies along the circumference of the dilated intrapericardial aorta. Two groups of aortic wall specimens, respectively harvested in the convexity and concavity of ascending aorta in 72 patients undergoing surgery for dilatation of the intrapericardial aorta associated with aortic valve disease, were separately sent for pathology, morphometry, and ultrastructural examination. Cystic medial necrosis, fibrosis, and elastic fiber fragmentation were classified into three degrees of severity; their mean degree and morphometric findings in the convexity and in the concavity specimens were compared by paired t-test. Correlation between echocardiographic degree of aortic dilatation and severity of medial degeneration was assessed separately for each of the two groups of specimens. Morphologically, medial degeneration was found in all cases; a higher mean degree was found in the convexity group (2.39 +/- 0.58 vs 1.44 +/- 0.65 in the concavity group; P < 0.001). At morphometry normal smooth muscle cells in the convexity specimens were significantly reduced (P = 0.007); the length (P = 0.012) and number (P = 0.009) of elastic fibers reduced and increased, respectively. Moreover, in the convexity specimens a significantly smaller amount of smooth muscle cells and an increase of immunohistochemical labeling of apoptosis-associated proteins in the subintimal layer of the media was noticed. Correlation between aortic ratio and medial degeneration degree was significant in the convexity group (P < 0.001), but not in the concavity group (P = 0.249). Scanning electron microscopy analysis confirmed morphological results and allowed us to better distinguish the early pathological cavities from the microvessels, which were in the outer media in normal aorta and ubiquitous in aortitis or atherosclerosis. Electron transmission microscopy analysis showed changes in the extracellular matrix and smooth muscle cells, and these changes increased from the intima to the adventitial layer of the media. In dilated intrapericardial aorta, medial degeneration changes and expression of apoptosis-associated proteins are more marked in the ascending aorta convexity, likely due to hemodynamic stress asymmetry. Ultrastructural findings allow us to distinguish the early medial changes not yet evident on light microscopy.

Aged↗

Aortic arch surgery: thoracoabdominal perfusion during antegrade cerebral perfusion may reduce postoperative morbidity.

BACKGROUND: This study aimed to assess the results of the introduction of thoracoabdominal perfusion (TAP) in the surgical strategy for aortic arch replacement with cerebral protection. METHODS: Two hundred two arch procedures performed with moderate hypothermia (22 degrees to 26 degrees C) and antegrade cerebral perfusion (ACP) were the objects of retrospective investigation. Acute type A dissection was the indication in 164 patients, aortic aneurysm in 38. In 80 patients, during ACP, the thoracoabdominal aorta was perfused either in an antegrade fashion through proximal descending aorta endoluminal cannulation (in 62 dissections), or retrograde through femoral artery cannulation with proximal descending aorta endoluminal occlusion (in 18 aneurysms). Hospital mortality and morbidity rates were compared between the two treatments (group A: ACP only, 122 patients; group B: ACP plus TAP, 80 patients) and the underlying aortic disease (dissection/aneurysm) was stratified. RESULTS: Cerebral perfusion (p = 0.008) and cardiopulmonary bypass times (p = 0.035) were significantly longer in group B. No complication related to the TAP technique was observed in group B. Overall hospital mortality was 12.9%, without significant difference between groups. No differences were found in terms of permanent neurological dysfunction between groups A (9.3%) and B (9.1%; p = 0.58). Group B patients showed lower rates of respiratory failure (18.2% versus 30.5% in group A; p = 0.038), shorter mechanical ventilation times (18.1 +/- 26 hours versus 57.9 +/- 70.1; p < 0.001) and lower incidence of acute renal failure (6.5% versus 18.6%; p = 0.012). Shorter intensive care and hospital stays were observed in group B (p = 0.02). CONCLUSIONS: The adjunction of TAP to ACP was associated with lower rates of end-organ complications, even in more extensive and time-consuming procedures.

Aortic Dissection↗

Achilles tendon for sternal synthesis in the treatment of mediastinitis.

Surgical approaches to postoperative mediastinitis that imply wire removal achieve earlier infection recovery but leave the patient with sternal instability. In 10 patients after wound surgical debridement, my colleagues and I achieved sternal synthesis by using Achilles tendons retrieved from multiorgan donors and stored in glutaraldehyde. Three tendons were used in each patient; they were passed through the bone at the manubrium and parasternally at the midsternum and the lower sternum. Thirty-day computed tomographic scan results, infection recovery, and quality of life were satisfactory.

Achilles Tendon↗

Postinfarction ventricular septal defect in a patient without coronary lesions.

A 46-year-old man with polycystic kidney disease was referred to our institution for ventricular septal defect complicating myocardial infarction. Cardiac catheterization disclosed normal coronary arteries and absence of myocardial bridging. None of the more frequent causes of thrombosis were present, and histopathology proved negative for acute myocarditis. The surgical procedure was successful and the 11-month follow-up uneventful.

Coronary Vessels↗

Aortic valve dysfunction and dilated ascending aorta. A complex and controversial association.

Several pathogenetic mechanisms account for the association of the ascending aorta dilation with aortic valve dysfunction. Functional aortic insufficiency can derive from medial degeneration of the aortic wall and annuloaortic ectasia; leaflet structural disease can determine root dilation by increasing aortic wall stress in case of both regurgitation and stenosis; aortic valve disease and aortic aneurysm can however coexist due to two different intrinsic etiologies. In the attempt to best tailor the surgical correction of such conditions to the underlying causative mechanism, several technical options have already been developed including composite or separate aortic valve and root replacement, valve-sparing operations, and aortoplasty techniques. The criteria for surgical indication cannot leave the underlying pathogenesis out of consideration as well. The newly acquired knowledge in the basic research on this topic is expected to affect the approach to the individual patient in the future.

Aorta↗

Extensive retroperitoneal fibrosis with duodenal and ureteral obstruction associated with giant inflammatory aneurysm of the abdominal aorta.

We report a case of abdominal aortic aneurysm complicated by retroperitoneal fibrosis with both duodenal and bilateral ureteral obstruction. The patient underwent successful bilateral transurethral ureteral stenting, and then he was referred for surgical treatment of the aneurysm. Massive retroperitoneal fibrosis was found at surgery, and the mass was removed along with the diseased aorta, which was replaced by a bifurcated Dacron prosthesis; duodenolysis and ureterolysis were concomitantly performed. Ureteral stents were removed on the 8th postoperative day. Follow-up assessment at 1 year showed normalization of the urinary tract structure at echography and good hemodynamic performance of the vascular prosthesis at Doppler examination. To our knowledge, no other case of duodenal and bilateral ureteral stenosis secondary to massive retroperitoneal reactive fibrosis in association with abdominal aortic aneurysm has been reported.

Aged↗

[Ways in which new surgical techniques have influenced the increasing use of cardiosurgery].

BACKGROUND: During the last decade new strategies and equipment have gained popularity in the clinical and experimental setting of cardiac surgery. Little is known about the real impact of these new approaches on the development of heart surgery. The present paper aimed to characterize, through a multicenter evaluation, the state of the art in Italy. METHODS: A survey of all active heart surgery centers in Italy (both public and private institutions) was conducted through a questionnaire. Diffusion, effectiveness and future perspective of these new surgical techniques were asked. Off-pump coronary artery surgery, myocardial revascularization in patients with low left ventricular ejection fraction, left ventricular surgical remodeling, mitral valve reconstruction, ministernotomic approach in aortic surgery and the use of laser, robots, heart port-access and endoscopy were the strategies under investigation. RESULTS: The use of laser, heart port-access and endoscopy were considered to have a poor impact due to proved ineffectiveness and/or technical complexity. Indications and long-term outcomes of off-pump coronary artery surgery are still under active debate. The introduction of new prosthetic materials has resulted in the widespread diffusion of mitral valve reconstruction approaches with concomitant widening of the indications. Similarly there is wide consensus on myocardial revascularization in patients with low ejection fraction. Ministernotomic strategies and ventricular remodeling are slowly but progressively gaining acceptance. CONCLUSIONS: Cardiac surgery in Italy is characterized by a great effort on new research field. Traditional approaches are still preferred unless new techniques have proved effective after strict scientific evaluation.

Cardiac Surgical Procedures↗

Cardiac metastases in malignant fibrous histiocytoma. A case report.

Malignant fibrous histiocytoma metastasizing to the left ventricle is an uncommon form of cardiac malignancy. This report describes a rare case of left ventricular metastases from a malignant fibrous histiocytoma of the posterior compartment of the right thigh, recurring five years after treatment with surgery, hyperthermic perfusion of the limb and radiotherapy. As the patient presented symptoms of cardiac tamponade, open heart surgery was performed through a median sternotomy; however, the tumor was not resectable and only a biopsy was performed. A partial response was obtained with standard and high-dose chemotherapy with peripheral blood progenitor cell transplantation. The response continued to improve with immunotherapy. The patient returned to normal physical activity. He died four years later due to a ventricular arrhythmia.

Adult↗