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Gianluca Bonanomi

Publications and source records attributed to Gianluca Bonanomi.

10 recordsLinked to original sources
PubMed2004

Changes in dolichol and pentosidine levels in the age-mismatched heterotopically transplanted rat heart.

To address some basic questions about primary and secondary events in the process of aging in different cell and tissue types, we studied changes in the levels of biomarkers of the aging cells (dolichol) and connective tissue (pentosidine) in the heart of older (22-month-old) Lewis rats heterotopically transplanted in younger (3-month-old) syngenic recipients. Results showed that age-mismatched transplantation did not alter the age-related accumulation of dolichol and significantly reduced the accumulation of pentosidine in cardiac tissue. It is concluded that aging of heart muscle and connective tissues is controlled by two independent clocks; that accumulation of dolichol in older tissues may be a primary consequence of the process of aging, whereas the accumulation of pentosidine may be secondary, perhaps to changes in circulating cells endowed with advanced glycation end products-specific receptors; in the perspective of organ transplantation, the environment of a younger host may positively interact with the graft and rejuvenate its collagen.

Aging↗
PubMed2003

A new device for beating heart bipolar radiofrequency atrial ablation.

OBJECTIVE: A technique for mimicking left atrial atriotomies using an ablation device that can be deployed without cardiopulmonary bypass has been developed. METHODS: In 12 healthy large (35-50 kg) adult pigs, maze-like ablation lesions were directly applied to the left atrial epicardium on the beating heart. The ablation device is irrigated, with a bipolar "hemostat" morphology, utilizing radiofrequency energy. Prior to and after ablation, left atrial electromechanical properties were measured during sinus rhythm in the latest 5 pigs using percutaneous endocardial catheter electromechanical mapping and intracardiac echocardiography. Pathologic analysis was performed acutely. RESULTS: All ablation lesions demonstrated conduction block along their entire course. Global left atrial conduction time (49.4 +/- 8.8 milliseconds before vs 58.8 +/- 9 milliseconds after) and pattern were not significantly altered. Although a significant amount (17.12% +/- 9%) of myocardium was either ablated or electrically isolated, ablation was not associated with significant alterations in global left atrial mechanics (left atrium ejection fraction 19% before vs 17% after; pulmonary vein peak flow velocity 1.22 m/s before vs 1.38 m/s after; peak mitral inflow velocity 2.34 m/s before vs 2.64 m/s after), mitral valve function, nor left ventricular function. There was no evidence of atrial thrombus formation. Transmurality was achieved in most lesions with no evidence of charring or barotrauma. CONCLUSIONS: Utilizing this ablation device, atrial lesions similar to the left component of the Maze procedure were deployed with uniform success in a beating heart without cardiopulmonary bypass or atriotomy and without adverse effects on left atrial electromechanics.

Animals↗
PubMed2003

Epicardium-based left atrial ablation: impact on electromechanical properties.

UNLABELLED: Epicardium-Based LA Ablation. INTRODUCTION: An important developmental task for surgical ablation of atrial fibrillation is simplification. A significant step would be the development of tools that create satisfactory ablation lesions without necessitating cardiopulmonary bypass or atriotomy. Optimally, these lesions would have no adverse impact on atrial electromechanical properties. METHODS AND RESULTS: We sought to characterize left atrial (LA) lesions created by a bipolar ablation device without cardiopulmonary bypass or atriotomy and to assess their impact on LA electromechanical properties. In each of five pigs, lesions were delivered to the epicardium of the beating heart, and encircled and connected right and left pulmonary vein vestibules and the atrial appendage. Before and after ablation, LA electromechanical properties were assessed using endocardial electromechanical mapping and intracardiac echocardiography. Postmortem histologic analysis also was performed. Each lesion was thrombus-free and barotrauma-free, histologically transmural, and a complete conduction barrier. Although a large aggregate area (24% +/- 6%) of LA myocardium was excluded, there was no significant change in global electromechanical properties. However, marked diminishment in appendage function was observed. CONCLUSION: Epicardium-based LA ablation in a beating heart could be achieved successfully without cardiopulmonary bypass or atriotomy. Although there was no adverse impact on global electromechanical properties, there was evidence of important regional diminishment.

Animals↗
PubMed2003

Left heart pacing lead implantation using subxiphoid videopericardioscopy.

INTRODUCTION: Recent clinical data support the utility of left heart pacing. The transvenous approach for left heart pacing lead implantation is imperfect. A direct epicardial approach may have advantages, but heretofore its utility has been limited because of the requirement for thoracotomy. We sought to examine the feasibility of a method for epicardial lead implantation that did not require thoracotomy. METHODS AND RESULTS: In five large swine, percutaneous access to the epicardium was achieved with subxiphoid videopericardioscopy, using a device that marries endoscopy with a port through which pacing leads could be introduced. In each animal, standard, active fixation pacing leads were implanted onto the left atrium and ventricle. The atrial lead was implanted at the base of the appendage. The ventricular lead was implanted on the anterior, lateral, and inferior walls. Continuous direct visualization of the epicardium provided guidance for lead localization and fixation, including avoidance of complications such as trauma to epicardial coronary vessels. Capture thresholds were uniformly low. Postmortem examination demonstrated anatomically accurate, uncomplicated lead fixation. CONCLUSION: Using subxiphoid videopericardioscopy, uncomplicated, anatomically accurate left heart epicardial pacing lead implantation can be achieved without thoracotomy.

Animals↗
PubMed2002

Experimental off-pump coronary bypass using a robotic telemanipulation system.

We hypothesized that a high-quality anastomosis between the left internal thoracic artery and the left anterior descending coronary artery could be constructed off-pump using a 4-degrees-of-freedom robotic telemanipulation system, endoscopic myocardial stabilization, and two-dimensional visualization. Nine swine were used. Three ports were created on the left chest for the endoscope and the two robotic arms, and another port was created on the right chest for the endostabilizer. Quality of anastomosis was assessed by angiography, analysis of flow, survival after proximal coronary ligation, and histopathology. All nine anastomoses were completed successfully in 22 +/- 3.6 minutes without the need for repair stitches. Left internal thoracic artery flow was 21.6 +/- 2.5 ml/min with diastolic dominant pattern. Eight animals (89%) survived for 60 minutes with the proximal left anterior descending coronary ligated. Angiographic patency was 100% with Fitzgibbon grade A in all. Histopathology of the anastomosis demonstrated minor changes in the integrity of the endothelium and the internal elastic lamina and absence of medial necrosis. We have demonstrated in our robotic off-pump coronary bypass model that a high-quality anastomosis can be constructed between the left internal thoracic artery and the left anterior descending coronary artery. These results support continued research towards robotic endoscopic off-pump CABG.

Anastomosis, Surgical↗
PubMed2002

A new live animal training model for off-pump coronary bypass surgery.

Training models are needed to perform accurate off-pump coronary artery bypass (OPCAB) surgery and to test evolving new technologies like minimally invasive devices and robotics. We describe a simple, effective and reproducible live animal training model to perform multiple arterial anastomoses on the beating heart that would maximize the use of available resources for training purposes.

Anastomosis, Surgical↗
PubMedDate not supplied

Laparoscopic repair of umbilical hernias in conjunction with other laparoscopic procedures.

BACKGROUND: This study evaluates the feasibility of laparoscopic transfascial suture repair of umbilical hernias when combined with another laparoscopic procedure that potentially contaminates the peritoneal cavity. METHOD: From August 1997 to November 2001, 32 patients underwent laparoscopic umbilical suture repair in association with another laparoscopic procedure. The repair was performed with the Carter-Thomason suture passer. RESULTS: Of the 32, 26 patients with more than 1-year follow-up were included in the study. The mean diameter of the umbilical hernia defect was 1.67 cm (range, 0.5 to 3). At a mean follow-up of 34 months (range, 12 to 60), there were only 2 recurrences (7.7%) both of which happened in patients with hernia defects larger than 2 cm in diameter. Apart from 2 wound infections, no other complications occurred. CONCLUSION: Laparoscopic suture repair of umbilical hernias with the suture passer method is effective and durable even when combined with other laparoscopic procedures that potentially contaminate the peritoneal cavity with bile or enteric contents.

Adult↗