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J N Fabiani

Publications and source records attributed to J N Fabiani.

At least 37 records · Page 2Linked to original sources
PubMed2000

Morphometric study of the pulmonary trunk: implications for a new approach of the Ross procedure.

A pulmonary valve autograft may be proposed to replace diseased aortic valves. The explanted pulmonary valve is replaced with a pulmonary homograft with the inherent risk of calcified degeneration. A monocusp valve using the anterior pulmonary trunk has been proposed to reconstruct the right ventricular outflow tract. The aim of this study was to determine the feasibility of this technique. In hearts from 17 adult cadavers, we measured: pulmonary trunk diameter at the leaflet tops (D1). H1 and H2 were respectively from leaflet top to lower and upper levels of the pulmonary trunk bifurcation. D2 = 1.4 D1 was calculated as the monocusp size allowing a 45 degrees opening of the valve and thus permitting good valvular efficacy. G = H1 - D2 determined the feasibility of the technique: G greater than 10 mm, appeared the most favorable, G between 0 and 10 mm, appeared possible, and G less than 0, appeared to be impossible. Mean values of D1, H1 and H2 were respectively: 20.19 mm, 37 mm and 57 mm. The technique was possible in 16 cases (94%) and impossible in 1 case (6%). Preoperative determination of these parameters, by echocardiography or magnetic resonance imaging, appears necessary before applying this new surgical technique.

Adult↗
PubMed2000

Influence of coronary artery and contralateral carotid artery status on long-term results of carotid artery surgery.

The main cause of death and long-term disability of patients undergoing carotid artery surgery is coronary artery disease. To identify the prognostic value of the status of the contralateral artery, we studied the course of 224 consecutive patients in whom one or both carotid arteries were operated on at our institution between 1985 and 1995. The 224 patients were divided into three groups: group I (n = 56) had an occluded contralateral carotid artery, in group II (n = 56) both carotids were operated on, and group III (n = 112) had a normal contralateral carotid artery. The clinical status of all patients except one was ascertained by one of us. We found that the status of the contralateral artery does not influence the long-term prognosis of patients undergoing carotid artery surgery. A periodic cardiological and vascular follow-up of these patients seems warranted to improve their survival.

Actuarial Analysis↗
PubMed2000

Bilateral carotid dissection and factor V mutation: a second case.

A young woman 38 years of age underwent Doppler ultrasonography following the spontaneous appearance of cervical pain causing loss of sleep. The examination revealed bilateral dissection of the internal carotid arteries, confirmed by supraaortic arteriography. Two successive CT scans showed no cerebral lesions. A thrombosis of the great saphenous vein was recorded as the only vascular event in her medical history. Thrombophilia was assessed following discovery of the dissection, and upon examination a heterozygotic mutation of Factor V Leiden was revealed. This observation is the second case of carotid dissection occurring in a subject presenting a factor V mutation. At the present time, however, there are no results to justify the assumption of a direct link between these two pathologies.

Adult↗
PubMed2000

Upper limb ischemia after subclavian flap aortoplasty: unusual long-term complication.

Repair of isolated coarctation of the aorta by subclavian flap aortoplasty carries the disadvantage of impaired blood supply to the left arm. However, ligation of branches of the subclavian artery can be tolerated without manifest ischemia of the upper extremity. We report the case of a young man who suffered from left upper extremity ischemia 18 years after initial operation. Treatment consisted of carotid-subclavian bypass with good outcome. The surgical approach of coarctation by subclavian aortoplasty should be reserved for specific cases, and if this procedure is performed, ligation of branches of the subclavian artery should be minimized to increase inflow into the left brachial artery.

Adolescent↗
PubMed2000

Platelets and prostacyclin in arterial bypasses: implications for coronary artery surgery.

BACKGROUND: We investigated effects of platelets and prostacyclin formation in human internal mammary (IMA) and radial (RA) arteries. METHODS: IMA and RA segments were suspended in organ bath with increasing concentrations of platelets. Experiments were applied with and without ketanserin, a 5HT2 receptor antagonist, or U3405, a TXA2 receptor antagonist. The release of prostacyclin (PGI2) was assessed by enzyme immunoassay in vessels without endothelium, before and after contraction with angiotensin (AT) I-II. RESULTS: In IMA and RA with endothelium, platelets caused contractions, significantly enhanced in arteries without endothelium. Contractions to platelets were higher in RA than in IMA. U3405 reduced the platelet induced contractions in RA but not in IMA. Ketanserin inhibited the platelet induced contractions in IMA and RA. The basal release of PGI2 was more important in IMA than in RA. Addition of AT/I-II significantly reduced the release of PGI2 in IMA but not in RA. CONCLUSIONS: The RA responds more powerfully to platelets than IMA. Protective system with PGI2 seems to be more powerless in RA than in IMA. This accentuates the importance of antispastic and antiplatelet drugs when arteries are used for coronary artery bypass surgery.

Angiotensin I↗
PubMed2000

Tolerance induced without immunosuppression in a T-lymphocyte suicide-gene therapy cardiac allograft model in mice.

BACKGROUND: Life-long immunosuppression is a major cause of mortality and morbidity in transplant recipients. Gene therapy could provide new ways to obtain tolerance and avoid indefinite immunosuppression. EpTK mice are derived from the FVB/N strain (H2q) and express the thymidine kinase gene of herpesvirus in all mature T cells. Thus any mature dividing T cell can be killed in the presence of ganciclovir. We investigated the survival of alloincompatible C57B1/6 (H2b) hearts heterotopically transplanted into EpTK mice given only ganciclovir from day 0 to day 7 or 14. METHODS: Abdominal cardiac transplantations were performed in 22 control mice (untreated FVB [n = 15], ganciclovir-treated FVB [n = 5], and untreated EpTK mice [n = 2]) and in 28 EpTK mice given ganciclovir from day 0 to day 7 (n = 15) or day 14 (n = 13). Rejection was defined as complete cessation of cardiac beat. Histologic examination of the grafts was performed at rejection, at day 7, or at day 100. Lymphocyte proliferation assays (concanavalin A stimulation or mixed lymphocyte reaction) were performed at day 7 and at day 100. RESULTS: All control animals rejected transplants in 7 days (range, 5-9 days), whereas indefinite survival (>100 days) was observed in 89% of the ganciclovir-treated EpTK group, irrespective of the duration of ganciclovir treatment. Graft histology showed extensive cellular infiltrates with myocyte necrosis and arteritis in the control animals but only a mild infiltrate without necrosis or arteritis in the ganciclovir-treated EpTK group. The proliferative responses of the tolerant mice at day 100 were identical to those of naive mice, including a preserved proliferation against the donor's lymphocytes in mixed lymphocyte reaction. CONCLUSION: Functional transplantation tolerance of a fully incompatible heart can be achieved without immunosuppressive drugs in this model of suicide gene therapy.

Analysis of Variance↗
PubMed2000

[Metaplasia of aortic tissue into tracheal tissue. Surgical perspectives].

Tracheal reconstruction after extensive resection remains an unsolved surgical problem. Numerous attempts have been made using tracheal grafts or prosthetic conduits with disappointing results. In this study, we propose a new alternative using an aortic autograft as tracheal substitute. In a first series of experiments, a half circumference of two rings was replaced with an autologous carotid artery patch. In a second series, a complete segment of trachea was replaced with an autologous aortic graft supported by an endoluminal tracheal stent. No dehiscence or stenosis was observed. Microscopic examinations at 3 and 6 months showed the replacement of the aortic tissue by tracheal tissue comprising neoformation of cartilage and mucociliary or non-keratinizing metaplastic polystratified squamous epithelium. Although these results need to be confirmed by a larger series of experiments, they showed that a vascular tissue placed in a different environment with a different function can be submitted to a metaplastic transformation which tends to restore a normal structure adapted to its new function. These remarkable findings offer new perspectives in tracheal reconstruction in human.

Animals↗
PubMed2000

Histochemical evidence for inducible nitric oxide synthase in advanced but non-ruptured human atherosclerotic carotid arteries.

In response to cytokine stimulation, the inducible isoform of the nitric oxide synthase (iNOS) produces large amounts of nitric oxide with potential consequences in the pathophysiology of atherosclerosis. Previous investigations have demonstrated the presence of iNOS in human atherosclerotic lesions. The goal of this study was to evaluate the occurrence of the expression of iNOS in ruptured versus non-ruptured human carotid atherosclerotic plaques. Using plastic-embedded sections, we performed in situ hybridization and immunohistochemistry on very advanced atherosclerotic lesions type V (non-ruptured) and type VI (ruptured) from 12 atheromatous carotid arteries from endarterectomy and six non-atherosclerotic internal mammary arteries from aorto-coronary bypass. Only one internal mammary artery expressed iNOS in the endothelium. In contrast, iNOS mRNA and protein were repeatedly expressed in advanced lesions type V in 5/7 cases, particularly in inflammatory regions. Specific cell markers identified iNOS-positive cells as macrophages and T-lymphocytes but also as smooth muscle cells and endothelial cells adjacent to these inflammatory regions. Nitration of protein tyrosines was not always associated to iNOS expression but more likely to the presence of inflammatory cells. In complicated lesions type VI, the occurrence of iNOS mRNA and protein expression diminished drastically (1/5 cases). Combined expression of iNOS mRNA and protein is frequently found in advanced but non-ruptured human atherosclerotic carotid lesions while it becomes rare after the plaque has ruptured. These findings suggest that iNOS could be an active participant in the plaque rupture event.

Aged↗
PubMed2000

Endovascular repair of aortic allograft aneurysmal degeneration: a case report.

Aortoenteric graft fistula remains a dreadful complication of aortic surgery. Good results have been reported using in situ graft replacement with arterial allografts. Late aneurysmal degeneration of the graft itself may necessitate further repair. We report the case of such an aneurysmal degeneration 7 years after implantation of the allograft. Endovascular repair was performed with a Vanguard device; complete exclusion was obtained immediately. At 6-month follow-up, the patient was alive and well. Duplex and computed tomography scans showed an excluded aneurysm with a slight reduction in size. Endovascular stent grafting may be a therapeutic option for treating patients with late allograft degeneration.

Aged↗
PubMed2000

[Cardiac fibroelastoma. Six operated cases and review of the literature].

The authors reviewed the cases of 6 patients operated between September 1994 and February 1999 for a rare benign tumour: papillary fibroelastoma of the heart. These patients, aged 51 +/- 14 years, all have single valvular involvement: mitral (N = 3), aortic (N = 2), tricuspid (N = 1). Five patients were symptomatic: transient ischaemic cerebral events (N = 3) associated with mesenteric infarction requiring ileal resection in 1 case; constituted cerebrovascular accident (N = 1); syncope (N = 1). In this last patient, the fibroelastoma was diagnosed fortuitously on the tricuspid valve. The features and location of the tumours were determined by transoesophageal echocardiography. Surgical treatment in all patients consisted in excising the tumour and preserving the valve. One aortic cusp was reconstructed after excising the tumour with a cryopreserved partial aortic homograft. Peroperative transoesophageal echocardiography confirmed the absence of regurgitation after the procedures in all patients. There were no postoperative complications in any of the cases. No cases of valvular regurgitation or of tumour recurrence were observed during follow-up. Despite the benign histology, cardiac fibroelastomas should be excised because of their embolic complications. Absence of recurrence justifies conservative reconstruction of the affected valve.

Adult↗
PubMed2000

Is 10 minutes the optimum immersion time in 0.6% glutaraldehyde for human pericardium?

BACKGROUND AND AIM OF THE STUDY: Pericardial fixation with 0.6% glutaraldehyde is usually assessed by measuring the shrinkage temperature of the tissue: the higher the shrinkage temperature, the greater the degree of cross-linking induced between collagen molecules. Animal pericardium studies have shown maximum response to be obtained after brief immersion (10 min). Our aim was to evaluate the effect of glutaraldehyde immersion time on shrinkage temperature of human pericardium which, to our knowledge, has not yet been studied. METHODS: Pericardial strips were harvested from 40 patients undergoing cardiac surgery. Time of immersion in glutaraldehyde ranged from 3 min to 6 months. Fresh untreated human pericardium samples were used as controls. The relationship between shrinkage temperature and time of treatment with glutaraldehyde was studied using a regression analysis. RESULTS: Glutaraldehyde treatment of pericardial tissues caused an increase in shrinkage temperature that was related biphasically to the time of immersion in glutaraldehyde. Mathematical expression of this curve permitted glutaraldehyde immersion time to be evaluated in relation to the degree of optimal shrinkage temperature. The time required for optimal fixation with glutaraldehyde, as measured by shrinkage temperature, was 100+/-0.77 min. CONCLUSION: Our results suggested that a 10-min exposure to glutaraldehyde was insufficient for 'correct' fixation of human pericardium. Inadequate glutaraldehyde exposure of human pericardium may explain mid and long-term failures reported with this tissue in cardiac surgery.

Bioprosthesis↗
PubMed2000

[Utilization of aortomyoplasty as a biological pumping system].

Aortomyoplasty is a surgical technique of constructing a neo-ventricle on the ascending or descending aorta with the latissimus dorsi muscle. This is electrically stimulated to contract during diastole, thereby creating a system of chronic, haemo-compatible aortic pumping. Long-term experimental studies have shown increases in cardiac output (from 3.6 to 5.5 l/min), decreases in peripheral resistances (from 1574 to 1134 dyne.sec.cm-5) and increases in indices of subendocardial viability (DPTI/TTI: 1.1 to 1.4). These experimental studies have been confirmed by the initial clinical results. To date, world experience includes thirty-six patients. With cardiomyoplasty, aortomyoplasty is a new arm in the therapeutic arsenal against severe cardiac failure by providing a new system of chronic circulatory assistance which is implantable and biocompatible.

Aorta, Thoracic↗
PubMed2000

[Human valvular substitutes for the treatment of complex progressive endocarditis. Application to aortic, mitral and tricuspid valves].

The aim of this study was to assess the immediate and long-term results of human valvular substitutes (homografts and autografts) in the treatment of complex progressive endocarditis in aortic, mitral and tricuspid valves. Since 1992, 80 patients (64 men, 16 women) aged 44 +/- 16 years (range 15 to 76 years), were treated. In 53 patients, the endocarditis involved native valves, 4 on previously plastified valves, or prosthetic valves in 27 patients. The endocarditis was recurrent 6 patients. The lesions were situated on the aortic valve (N = 59), mitral valve (N = 5), aortic and mitral valves (N = 12), aortic and tricuspid valves (N = 3), mitral and tricuspid valves (N = 1). The peroperative findings confirmed the lesions diagnosed at echocardiography: prosthetic valve dehiscence (27 patients), prosthetic cusp tear (N = 7), vegetations (N = 61), perforations (N = 48), periannular abscess (N = 47), aorto-ventricular discontinuity (N = 12), aorto-mitral discontinuity (N = 7), right ventricular aortic fistula (N = 1), aorto-pulmonary fistula (N = 1), pseudo-aneurysm (N = 1), ventricular septal defect (N = 1). Eighty-six human valvular substitutes were used (double homograft in 6 patients): aortic homograft (N = 63), pulmonary in the aortic position (N = 1), the mitral position (N = 12), of which 8 were in the mitral and 4 in the tricuspid position, pulmonary autograft (N = 10). Ten mitral valve repairs were performed on infected lesions. Associated procedures included mitral valve repair (N = 5), tricuspid valve repair (N = 1) for non-infarcted valve lesions, replacement of the ascending aorta (N = 2), the aortic arch (N = 1), coronary bypass surgery (N = 2) and one nephrectomy. The hospital mortality was 5% (4 patients). The causes of death were: infarction (N = 2), myocardial failure (N = 1) and multiorgan failure (N = 1). Four early reoperations were required for technical problems, none for endocarditis. Seventy-three of the 76 survivors were followed up for 43 +/- 24 months (range 1 to 84 months). Eight patients died during follow-up, but only 1 of cardiac causes (operation for recurrent endocarditis in a drug abuser). Seven operations were performed, 3 for technical problems or structural failure, 4 for recurrent endocarditis. At 5 years' follow-up, the survival was 81 +/- 5%; 88 +/- 6% of patients were free of endocarditis, 77 +/- 6% had no reoperation: no patient had thromboembolic complications. These results show that human valvular substitutes are adapted for the treatment of complex, progressive aortic, mitral and tricuspid valve endocarditis when techniques of valvular repair are no longer feasible.

Adolescent↗
PubMed2000

Coronary reoperations: indications, techniques and operative results. Retrospective study of 240 coronary reoperations.

BACKGROUND: We review twelve-year experience with coronary reoperations so as to better identify indications, techniques and results. METHODS: Between January 1986 and March 1998, 240 coronary reoperations (228 redux, 12 tridux) were performed. There were 223 male and 17 female patients, with a mean age of 63.6+/-7.9 years at the time of reoperation. Mean time interval between operations was 10+/-4.8 years. Symptomatology consisted of: stable recurrent angina (40%), unstable (57%), or congestive heart failure (3%). Pathological feature of the primary grafts was implicated in 95% of cases and atheroma sole progression over native network in 5% of cases. During reoperations 521 (2.2+/-0.8/patient) bypass [venous (40%), arterial (60%)] were performed as well as 15 associated procedures. RESULTS: Operative mortality represented 10% (n=24). Causes of death included infarct (7), left ventricular failure (12), rhythm disorders (2), mediastinitis (1) and multiorgan failure (2). Mortality risk factors were operation date (16.6% before 1992 and 7.4% after, p=0.03), age (13.1% after 60 years old, 2.7% before, p=0.01) time interval between intervention (12% after 8 years, 4% before, p=0.05) and anterograde cardioplegia only (11.8% versus 4.5% when a combined anterograde and retrograde access was used, p=0.06). Morbidity was 31% (71/240). Among the survivors 169 patients (78%) did not experience any complication. CONCLUSIONS: Thanks to a better medico-surgical management, the mortality rate of coronary reoperations is steadily decreasing.

Aged↗
PubMed1999

Single breath exhaled nitric oxide in lung transplant patients: a preliminary clinical study.

Exhaled nitric oxide is considered as a marker of airway inflammation. We report here our preliminary experience with single-breath exhaled nitric oxide measured in lung transplant patients with and without bronchiolitis obliterans syndrome and in cardiac transplant patients. Peak and end-expiratory nitric oxide concentrations did not differ between groups, but single-breath exhaled nitric oxide recordings were strikingly different in patients suffering from bronchiolitis obliterans syndrome, with a slower decrease from peak to end-expiratory nitric oxide concentration. Further studies are required in order to determine whether theses abnormalities reflect the inflammatory process of bronchiolitis obliterans syndrome.

Adult↗
PubMed1999

[Do the long-term results of carotid surgery influence the status of the contralateral carotid artery?].

AIM: The main cause of long-term death and disability of patients undergoing carotid artery surgery is coronary artery disease. To identify the prognostic value of the status of the contralateral artery, we studied the course of 224 patients operated consecutively on one or both carotid arteries in the same institution between 1985 and 1995. PATIENTS AND METHODS: The 224 patients were divided into three groups: group I (n = 56) having an occluded contralateral carotid artery; group II (n = 56) in which both carotids were operated on; and, group III (n = 112) having a normal contralateral carotid artery. The clinical status of all patients was ascertained by one of us for all patients except one. This study concerned also the course of 40 patients (group R) belonging to the three groups, who had during the follow-up period a coronary and/or a peripheral vascular intervention with a preoperative coronarography. RESULTS: The median follow-up was 62.8, 78 and 65 months for groups I, II and III, respectively. Actuarial survival rates were 67%, 73%, 72.5% at 5 years, and 39%, 51.5% and 42% at 10 years, for group I, II and III respectively. Actuarial stroke-free rates were 96%, 100%, 91% at 5 years, and 96%, 100% and 78.5% at 10 years for group I, II and III respectively. Actuarial cardiac death rates were 26%, 23%, 19% at 5 years, and 49%, 42% and 37% at 10 years for group I, II and III, respectively. None of the differences between the three groups regarding these three different end-points was significant. The group R fatal or non-fatal cardiac event-free rates at 5 and 10 years were 88% and 53% respectively. When compared with the rates of other patients (without revascularization): 68% and 25.5% at 5 and 10 years, the results were almost significant (P = 0.07). Average age for group R patients was significantly lower (65 vs. 69 years, P < 0.05). Using Cox's model, age alone emerged as a factor influencing survival (P = 0.07) but not revascularization (P = 0.13). CONCLUSION: The status of the contralateral artery does not influence the long-term prognosis of patients undergoing carotid artery surgery. A periodic cardiological and vascular follow-up of these patients tends to improve their survival.

Actuarial Analysis↗
PubMed1999

Aortic dissection of Kommerell's diverticulum in Marfan's syndrome.

We report a surgical case of chronic aortic dissection with an entrance tear on Kommerell's diverticulum, a rare embryologic anomaly, with an extension to the arteria lusoria, in a patient with Marfan's syndrome. The operation consisted of aortic root and arch replacement with reimplantation of the right subclavian artery in the right carotid artery under circulatory arrest and deep hypothermia.

Adult↗