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Gaetano Thiene

Publications and source records attributed to Gaetano Thiene.

At least 91 records · Page 5Linked to original sources
PubMed2003

Long-term durability of the Hancock II porcine bioprosthesis.

BACKGROUND: Survival and prosthetic complications of patients receiving the Hancock II second-generation bioprosthesis (Medtronic, Inc, Minneapolis, Minn) in the aortic, mitral, mitral-aortic, and tricuspid positions were analyzed at 15 years' follow-up. METHODS: Between May 1983 and December 1993, 212 patients (104 men and 108 women; mean age, 63 +/- 9 years; age range, 29-81 years) received 66 aortic, 114 mitral, 26 mitral-aortic, and 6 tricuspid Hancock II valves. Thirty-one percent of patients had previous valve operations, 15% had concomitant cardiac procedures, and 87% were in New York Heart Association class III or IV. Follow-up included 1704 patient-years and was 98% complete, with a median of 9 patient-years (range, 0.013-17.4 years). Forty-six patients were at risk at 14 to 15 years, and 30 were at risk after 15 years. RESULTS: One hundred twenty-two (57%) of 212 patients died, 20 of them perioperatively. Fifteen-year actuarial Kaplan-Meier survival was 35.2% +/- 3.8%, and freedom from valve-related mortality was 84% +/- 3.5%, with no difference on the basis of position or age (<65 or >or=65 years). Percentages for freedom from thromboembolism, anticoagulant-related hemorrhage, endocarditis, and paravalvular leak were, respectively, 78.2% +/- 4%, 83.5% +/- 3.6%, 95.7% +/- 2%, and 97.3% +/- 1.4%, with no significant difference between the aortic and mitral positions. Freedom from structural valve deterioration was 71.8% +/- 5.6%: 88.9% +/- 6.2% in the aortic position versus 59.5% +/- 3.9% in the mitral position (P =.01) and 64.3% +/- 3% in the mitral-aortic position. In patients younger than 65 years, actual freedom from structural valve deterioration was less than that seen in older patients (84.5% +/- 3.5% vs 95% +/- 3.0%) and was better in the aortic versus the mitral position (92% +/- 4.5% vs 82% +/- 4.2%). CONCLUSION: The Hancock II porcine valve showed excellent 15-year durability. We recommend its use in patients 65 years of age, as well as in younger patients undergoing aortic replacement.

Adult↗
PubMed2003

Hancock II bioprosthesis: a glance at the microscope in mid-long-term explants.

BACKGROUND AND OBJECTIVES: The Hancock II bioprosthesis is a second-generation porcine valve xenograft treated with the detergent sodium dodecyl sulphate (T6) to retard calcification. The aim of this investigation was to study the gross and microscopic features in Hancock II explants to assess the structural changes occurring with time. METHODS: Among 1382 Hancock II bioprostheses (701 isolated aortic, 421 isolated mitral, 130 double) implanted from 1983 to 1997 in 1252 patients, 22 (16 mitral, 6 aortic) were removed at reoperation until 1999 and were available for pathological investigation: infective endocarditis occurred in 5 and structural deterioration in 8, whereas in the remaining 9 xenografts reoperation was performed for nonstructural valve deterioration (paravalvular leak in 4 and prophylactic replacement in 5). Morphological investigation consisted of gross examination and x-ray, histologic, immunohistochemistry, electron microscopic, and atomic absorption spectroscopic examination. RESULTS: The cause of structural valve deterioration was dystrophic calcification in 4 cases (1 aortic, 3 mitral; range of time graft was in place, 101 to 144 months), non-calcium-related tears in 3 cases (all mitral, range 121 to 163 months), and commissural dehiscence in 1 (aortic, range 156 months). Five of the nonstructural valve deterioration explants (range 42 to 122 months) showed only pinpoint mineralization at the commissures. Mean calcium content in nonstructural deterioration explants was 14.70 +/- 22.33 versus 99.11 +/- 81.52 mg/g in explants with structural valve deterioration. Electron microscopic examination showed early nuclei of mineralization mostly consisting of calcospherulae upon cell debris. Local or diffuse lipid insudation was observed in all but 2 explants and consisted of cholesterol clefts, lipid droplets, and lipid-laden macrophages featuring foam cells. The lipid insudation was the most plausible cause of tearing in 2 explants. CONCLUSIONS: These pathologic findings support the clinical results of a delayed occurrence of structural failure of Hancock II bioprostheses and a mitigation of mineralization by the anti-calcification treatment. However, other factors such as lipid insudation may come into play in the long term.

Aged↗
PubMed2003

Successful treatment of enterovirus-induced myocarditis with interferon-alpha.

No randomized, placebo-controlled studies have investigated interferon-alpha therapy in enterovirus-proven myocarditis. This report describes 2 patients with enterovirus-induced myocarditis (1 with associated Churg-Strauss syndrome) who at follow-up endomyocardial biopsy showed clinical and hemodynamic improvement and viral clearance (using polymerase chain reaction) after interferon-alpha therapy.

Adult↗
PubMed2003

Methotrexate for immunosuppression in life-supporting pig-to-cynomolgus monkey renal xenotransplantation.

Methotrexate (MTX) has been used successfully as an immunosuppressant in rodent xenotransplantation models, but the data generated so far with MTX in pig-to-baboon cardiac transplantation studies have been disappointing. The potential of this agent was consequently explored in a life-supporting pig-to-primate renal model using the cynomolgus monkey as the recipient species. Introductory in vitro and in vivo pharmacokinetic and pharmacodynamic studies with MTX were conducted in three cynomolgus monkeys. Subsequently, 10 cynomolgus monkey recipients of a life-supporting kidney from human decay-accelerating factor transgenic pigs were administered MTX intravenously according to three different regimens. All the animals also received cyclosporine A and steroids. In addition, mycophenolate sodium (MPS) was administered post-operatively in two of the three groups of transplanted animals. At clinically relevant concentrations, MTX is able in vitro to inhibit the mixed lymphocyte reactions (MLR) in cynomolgus monkeys. After intravenous administration, moreover, exposure of cynomolgus monkeys to MTX appeared to be higher than had been previously reported in baboons. Graft function was observed in the transplanted animals, which survived from 0 to 41 days. All but two animals revealed acute humoral rejection in the explanted graft and developed diarrhea. Diarrhea was the cause of euthanasia in five cases. It was unrelated to the administration of MPS and associated with severe histopathological signs of enteritis. This study demonstrates that the pharmacokinetic and pharmacodynamic profiles if MTX vary substantially between non-human primate species. In vitro, MTX has immunosuppressive properties in the cynomolgus monkey at clinically relevant concentrations. In vivo, MTX has a very narrow therapeutic window in cynomolgus monkeys, however, as it does in baboons. We conclude that MTX is scarcely effective as an immunosuppressant, be it for induction or maintenance, in pig-to-cynomolgus monkey renal xenotransplantation.

Animals↗
PubMed2003

Coronary thrombosis and sudden death after an enteroviral infection. Case report.

We report the case of a 26-year-old man who died suddenly 9 days after an episode of flu. Microscopic examination of the left anterior descending coronary artery showed an eccentric fibroatheromatic plaque complicated by thrombosis, endothelial erosion and extensive T-cell and macrophage infiltration. Frozen sections of the thrombotic coronary segment, analysed for different infective agents by polymerase chain reaction (PCR) and reverse transcriptase (RT)-PCR, showed positive amplification for an enteroviral genome. Enteroviral infection may play an important role in coronary plaque instability and may precipitate thrombotic occlusion.

Adult↗
PubMed2003

Arrhythmogenic right ventricular cardiomyopathy type 1 (ARVD1): confirmation of locus assignment and mutation screening of four candidate genes.

Arrhythmogenic right ventricular cardiomyopathy type 1 (ARVD1) is an autosomal dominant disorder characterised by progressive degeneration of right ventricular myocardium, arrhythmias and risk of sudden death. By linkage analysis, we previously mapped the involved gene to chromosome 14q24.3. In the present study we report on linkage analysis of one additional and unrelated family, which enabled to confirm previous locus assignment. Another family is reported, in which genetic and clinical data suggest linkage to the same locus. Direct sequencing of DNA from individuals belonging to established ARVD1 families failed to detect causative mutations in exonic sequences of four genes (POMT2, TGFbeta3, KIAAA1036 and KIAA0759) expressed in the heart and which defects could possibly induce plasma membrane instability or apoptosis, key features of ARVD pathogenesis.

Adult↗
PubMed2003

Noninvasive risk stratification in arrhythmogenic right ventricular cardiomyopathy.

The natural history of arrhythmogenic right ventricular cardiomyopathy is determined by the electrical instability of the dystrophic myocardium, which can precipitate arrhythmic cardiac arrest any time during the course of the disease and by the progressive myocardial loss that results in ventricular dysfunction and heart failure. Sudden death accounts for the majority of the fatal events but its occurrence is mostly unpredictable. There are no prospective and controlled studies assessing clinical markers that can predict the occurrence of life-threatening ventricular arrhythmias. However, the noninvasive risk profile, which emerges from retrospective analysis of clinical and pathologic series, is characterized by history of syncope, physical exercise, spontaneous ventricular tachycardia or ventricular fibrillation, right ventricular dysfunction, left ventricular involvement, right precordial negative T wave, right bundle branch block, QT-QRS dispersion, right precordial ST-segment elevation and late potentials. At present only QRS dispersion, history of syncope and right and/or left ventricular abnormalities at radionuclide angiography proved to be independent noninvasive predictors of sudden death.

Arrhythmogenic Right Ventricular Dysplasia↗
PubMed2003

Full-sternotomy off-pump versus on-pump coronary artery bypass procedures: in-hospital outcomes and complications during one year in a single center.

We prospectively compared, according to their preoperative clinical profiles, the in-hospital outcomes of patients operated on consecutively (but without randomization) for isolated coronary artery disease with on-pump or off-pump techniques. During 2001, 324 patients underwent coronary artery bypass grafting: 216 patients (mean age, 66.7 +/- 8.9 years; range, 41-85 years) underwent on-pump revascularization, and 108 patients (mean age, 676 +/- 10 years; range, 37-90 years) underwent full-sternotomy off-pump revascularization. The 2 groups were homogeneous with regard to female sex (22.6% vs 26.8%), previous cardiac operation (2.8% vs 4.6%), cardiogenic shock (1.3% vs 1.9%), diabetes (30% vs 33%), and chronic renal failure that required hemodialysis (3% vs 3.5%). Postoperative complications, including bleeding, myocardial infarction, acute renal failure, mediastinitis with sternal dehiscence, cerebrovascular events, and prolonged respiratory assistance were more frequent in on-pump patients (P = 0.004). The total number of grafts and the grafts per patient ratio were significantly higher in on-pump patients (P = 0.0001), whereas the total number of full arterial revascularizations was higher in off-pump patients (P = 0.0001). Off-pump patients showed a significantly shorter intensive care unit stay (P = 0.02), and less need for intra-aortic balloon pump insertion (P = 0.04). In-hospital mortality was 2.8% in on-pump patients and 2.7% in off-pump patients (P = NS). Although the hospital mortality rate was comparable for the 2 techniques, the in-hospital comparison between the 2 groups showed how the avoidance of cardiopulmonary bypass can significantly reduce the cumulative postoperative incidence of complications in patients undergoing coronary artery bypass grafting.

Adult↗
PubMed2002

Recurrence of idiopathic pulmonary hemosiderosis in a young adult patient after bilateral single-lung transplantation.

BACKGROUND: Idiopathic pulmonary hemosiderosis (IPH) is a rare disease of unknown etiology characterized by hemoptysis, diffuse pulmonary infiltration, and anemia. Diagnosis requires a detailed clinical history and transbronchial lung biopsy (TLB). METHODS AND RESULTS: A 19-year-old man developed progressive dyspnea, hemoptysis, and anemia. The chest x-rays showed bilateral opacities. IPH was diagnosed on the basis of clinical findings and TLB. The patient was treated with corticosteroidal therapy. His respiratory function worsened, and he underwent lung transplantation in 1997. The pathological examination on native lungs confirmed the previous histologic diagnosis. In 2000, the patient again developed hemoptysis, fever, and hypoxemia. A recurrence of the disease was established by TLB. CONCLUSIONS: This is the first report of recurring IPH. The possibility of recurrent IPH raises the question whether these patients should be disqualified from lung transplantation. This question is unanswerable because incidence of recurrence, time course, and impact on the graft function are presently unknown and unpredictable.

Adult↗
PubMed2002

Mutation in human desmoplakin domain binding to plakoglobin causes a dominant form of arrhythmogenic right ventricular cardiomyopathy.

Arrhythmogenic right ventricular cardiomyopathy (ARVD/C) is a genetically heterogeneous disease characterized by progressive degeneration of the right ventricular myocardium and increased risk of sudden death. Here, we report on a genome scan in one Italian family in which the disease appeared unlinked to any of the six different ARVD loci reported so far; we identify a mutation (S299R) in exon 7 of desmoplakin (DSP), which modifies a putative phosphorylation site in the N-terminal domain binding plakoglobin. It is interesting that a nonsense DSP mutation was reported elsewhere in the literature, inherited as a recessive trait and causing a biventricular dilative cardiomyopathy associated with palmoplantar keratoderma and woolly hairs. Therefore, different DSP mutations might produce different clinical phenotypes, with different modes of inheritance.

Adolescent↗
PubMed2002

Screening for ryanodine receptor type 2 mutations in families with effort-induced polymorphic ventricular arrhythmias and sudden death: early diagnosis of asymptomatic carriers.

OBJECTIVES: We sought to establish the role of genetic screening for ryanodine receptor type 2 (RyR2) gene mutations in families with effort-induced polymorphic ventricular arrhythmia (PVA), syncope and juvenile sudden death. BACKGROUND: The RyR2 mutations have been associated with PVA, syncope and sudden death in response to physical or emotional stress. METHODS: We studied 81 subjects (39 males and 42 females; mean age 31 +/- 20 years) belonging to eight families with pathogenic RyR2 mutations. All subjects underwent screening for RyR2 mutations, electrocardiography (ECG), 24-h Holter monitoring, signal-averaged electrocardiography (SAECG), two-dimensional echocardiography and exercise stress testing. Electrophysiologic (EP) study was performed in nine patients. RESULTS: Six different RyR2 mutations were found in eight families. Forty-three family members carried the gene mutation. Of these, 28 (65%) showed effort-induced arrhythmic symptoms or signs and one died suddenly during follow-up. Family history revealed 19 juvenile cases of sudden death during effort or emotion. In two families sharing the same mutation, no subject presented with PVA during the stress test; thus, sudden death and syncope were the only clinical manifestations. The 12-lead ECG was normal in all but two subjects, whereas five patients showed positive late potentials on the SAECG. In 17 (39.5%) of 43 subjects, the two-dimensional echocardiogram revealed localized kinetic abnormalities and mild structural alterations of the right ventricle. The EP study was not able to induce PVA. CONCLUSIONS: The absence of symptoms and PVA on the stress test in more than one-third of carriers of RyR2 mutations, as well as the lack of PVA inducibility by the EP study, underlies the importance of genetic screening for the early diagnosis of asymptomatic carriers and prevention of sudden death.

Adolescent↗
PubMed2002

Directional atherectomy of a calcified lesion using a new atherectomy device.

We report on a case of directional atherectomy performed on a calcified coronary lesion using a novel device with a hardened titanium cutter. The successful removal of calcified plaque was documented by intravascular ultrasound assessment and confirmed by histopathological analysis of the obtained plaque specimen.

Atherectomy, Coronary↗
PubMed2002

Endothelin A-receptor antagonist administration immediately after experimental myocardial infarction with reperfusion does not affect scar healing in dogs.

OBJECTIVE: Endothelin (ET) receptor antagonists have been reported to reduce both infarct size and no-reflow phenomenon; however, in rat models their effect on the healing process after myocardial infarction (MI) is controversial. The study aimed to evaluate the effect of early administration of the ET(A) receptor antagonist darusentan on scar healing in an ischemia-reperfusion model in dogs. METHODS: Thirty male mongrel dogs surviving 180 min left anterior descending coronary artery balloon occlusion were randomised to: darusentan i.v. bolus-5 mg/kg 5 min before reperfusion-(group I); darusentan i.v. bolus+chronic oral-10 mg/kg/day-(group II); saline (group III). Five age-matched dogs served as controls (group IV). At 6 weeks weight, volume, mass/volume, wall thickness, thinning ratio and expansion index were assessed in the explanted hearts. Infarct size and scar area tissue composition were evaluated by computerized histomorphometry. Cellularity, vessels and TGFbeta in the scar area were scored by immunohistochemistry. RESULTS: 24 dogs (80%; 7 group I, 8 group II, 9 group III) developed an anterior MI, transmural in 15 and subendocardial in 9, mean size 11.5+/-4% of left ventricular area and 37+/-9% of left ventricular endocardial circumference. MIs were homogeneously distributed among the three groups regarding either infarct size or transmural extent. No differences were found in the three MI groups regarding thinning ratio, expansion index and scar area tissue characterization. Percent scar collagen content (37+/-17 vs. 53+/-20 vs. 46+/-14), myofibroblasts (1.2 vs. 1.3 vs. 1.4), macrophages (1.2+/-0.5 vs. 1.3+/-0.5 vs. 1.4+/-0.5), neovessels (2.8+/-0.4 vs. 2.6+/-0.5 vs. 2.9+/-0.3) and TGFbeta score (2 vs. 2.25 vs. 2.11) were not significantly different. CONCLUSIONS: Early administration of the ET(A) receptor antagonist darusentan does not affect the scar healing process at 6 weeks after experimental MI with reperfusion in dogs.

Administration, Oral↗