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Biomedical subjects

Gaetano Thiene

Publications and source records attributed to Gaetano Thiene.

At least 37 records · Page 2Linked to original sources
PubMed2005

Frequency of bicuspid aortic valve in young male conscripts by echocardiogram.

The database of echocardiographic examinations performed during the military screening of 20,946 young men in northeastern Italy was systematically reviewed to assess the frequency, hemodynamic characteristics, and aortic sizes of subjects with bicuspid aortic valves (BAVs). One hundred sixty-seven patients with BAVs were identified (0.8%), of whom 80 (48%) were diagnosed de novo during military screening. Aortic insufficiency was the predominant hemodynamic lesion in 110 subjects (66%), mild in 90, and moderate to severe in 20. Patients with BAVs displayed larger aortic sizes than controls at each aortic level, and the degree of dilation was related to the presence but not the severity of aortic insufficiency.

Adolescent↗
PubMed2005

Host-derived circulating cells do not significantly contribute to cardiac regeneration in heterotopic rat heart transplants.

OBJECTIVES: The aim of this study was to investigate the contribution of host-derived circulating cells to cardiac repair after tissue damage using the model of heterotopic heart transplantation between transgenic recipient rats expressing green fluorescent protein (GFP) and wild-type donors. METHODS: Unlabeled donor rat hearts, some of which underwent prolonged cold ischemia pretreatment, were transplanted into the abdominal cavity of GFP+ transgenic recipient rats and were analyzed 15 and 90 days after surgery. An additional experimental group underwent heart transplantation following administration of granulocyte-colony stimulatory factor (G-CSF) to mobilize bone marrow cells. RESULTS: Most transplants contained GFP+ mature cardiomyocytes. However, systematic counting in the transplants showed that the proportion of GFP+ cardiomyocytes was only 0.0005% to 0.008% of all cardiomyocytes. These relative proportions did not change after G-CSF treatment, despite evidence for sustained marrow cell mobilization. Confocal image analysis showed that the majority of GFP+ cardiomyocytes contained a high number of nuclei, suggesting that these cells may derive from fusion events. Very rarely, small GFP+ undifferentiated cells, expressing GATA-4, were also identified. Occasionally, GFP+ endothelial cells, but not smooth muscle cells, were detected in blood vessels of some transplants. CONCLUSIONS: Our results demonstrate that cardiomyocytes expressing a host transgenic marker are detectable in heterotopic heart transplants; however, they do not significantly contribute to repopulation of the damaged myocardium.

Animals↗
PubMed2005

Clinical profile of four families with arrhythmogenic right ventricular cardiomyopathy caused by dominant desmoplakin mutations.

AIMS: To characterize the clinical profile of patients belonging to families affected with autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) due to mutations of the gene encoding for the cell-to-cell adhesion protein desmoplakin (DSP). METHODS AND RESULTS: Thirty-eight subjects belonging to four families showing different DSP mutations (three missense and one in the intron-exon splicing region) underwent clinical and genetic investigation, including annual 12-lead ECG, signal averaged ECG, 24 h Holter ECG, and two-dimensional echocardiography. Twenty-six family members (11 males and 15 females) were found to carry a DSP mutation. After a follow-up of 1-24 years, median 6, 14 (54%) fulfilled (mean age at diagnosis 33+/-15 years) and 12 (mean age 43+/-24 years at the last follow-up) did not fulfil the established diagnostic criteria of ARVC, although five of them had some cardiac abnormalities. Clinical presentations were palpitations in six, sudden death (SD) in three, syncope in one, and chest pain with increased myocardial enzymes in two. Abnormal 12-lead ECG findings were present in 15 cases (58%), ventricular arrhythmias in 12 (46%), and late potentials in 11 (42%). Fourteen (54%) had abnormal echocardiographic findings, with left ventricular involvement in seven of them. SD occurred in six subjects and in three it was the first symptom of the disease; moreover, one subject died due to heart failure. The annual disease-related death and SD/aborted SD were 0.028 and 0.023 patient/year, respectively. CONCLUSION: Familial ARVC caused by DSP mutations is characterized by a high occurrence of SD even as first clinical manifestation. Left ventricular involvement is not a rare feature of the disease, which frequently escapes clinical diagnosis by applying the currently available criteria. Genetic screening is mandatory for early identification of asymptomatic carriers and preventive strategies within a family with a genotyped index case.

Adolescent↗
PubMed2005

Three-dimensional electroanatomic voltage mapping increases accuracy of diagnosing arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: Three-dimensional electroanatomic voltage mapping offers the potential to identify low-voltage areas that correspond to regions of right ventricular (RV) myocardial loss and fibrofatty replacement in patients with arrhythmogenic RV cardiomyopathy/dysplasia (ARVC/D). METHODS AND RESULTS: Thirty-one consecutive patients (22 men and 9 women; mean age, 30.8+/-7 years) who fulfilled the criteria of the Task Force of the European Society of Cardiology and International Society and Federation of Cardiology (ESC/ISFC) for ARVC/D diagnosis after noninvasive clinical evaluation underwent further invasive study including RV electroanatomic voltage mapping and endomyocardial biopsy (EMB) to validate the diagnosis. Multiple RV endocardial, bipolar electrograms (175+/-23) were sampled during sinus rhythm. Twenty patients (group A; 65%) had an abnormal RV electroanatomic voltage mapping showing > or =1 area (mean 2.25+/-0.7) with low-voltage values (bipolar electrogram amplitude <0.5 mV), surrounded by a border zone (0.5 to 1.5 mV) that transitioned into normal myocardium (>1.5 mV). Low-voltage electrograms appeared fractionated with significantly prolonged duration and delayed activation. In 11 patients (group B; 35%), electroanatomic voltage mapping was normal, with preserved electrogram voltage (4.4+/-0.7 mV) and duration (37.2+/-0.9 ms) throughout the RV. Low-voltage areas in patients from group A corresponded to echocardiographic/angiographic RV wall motion abnormalities and were significantly associated with myocyte loss and fibrofatty replacement at EMB (P<0.0001) and familial ARVC/D (P<0.0001). Patients from group B had sporadic disease and histopathological evidence of inflammatory cardiomyopathy (P<0.0001). During the time interval from onset of symptoms to the invasive study, 11 patients (55%) with electroanatomic low-voltage regions received an implantable cardioverter/defibrillator because of life-threatening ventricular arrhythmias, whereas all but 1 patient with a normal voltage map remained stable on antiarrhythmic drug therapy (P=0.02). CONCLUSIONS: Three-dimensional electroanatomic voltage mapping enhanced accuracy for diagnosing ARVC/D (1) by demonstrating low-voltage areas that were associated with fibrofatty myocardial replacement and (2) by identifying a subset of patients who fulfilled ESC/ISFC Task Force diagnostic criteria but showed a preserved electrogram voltage, an inflammatory cardiomyopathy mimicking ARVC/D, and a better arrhythmic outcome.

Adult↗
PubMed2005

Cardiovascular pre-participation screening of young competitive athletes for prevention of sudden death: proposal for a common European protocol. Consensus Statement of the Study Group of Sport Cardiology of the Working Group of Cardiac Rehabilitation and Exercise Physiology and the Working Group of Myocardial and Pericardial Diseases of the European Society of Cardiology.

The 1996 American Heart Association consensus panel recommendations stated that pre-participation cardiovascular screening for young competitive athletes is justifiable and compelling on ethical, legal, and medical grounds. The present article represents the consensus statement of the Study Group on Sports Cardiology of the Working Group on Cardiac Rehabilitation and Exercise Physiology and the Working Group on Myocardial and Pericardial diseases of the European Society of Cardiology, which comprises cardiovascular specialists and other physicians from different European countries with extensive clinical experience with young competitive athletes, as well as with pathological substrates of sudden death. The document takes note of the 25-year Italian experience on systematic pre-participation screening of competitive athletes and focuses on relevant issues, mostly regarding the relative risk, causes, and prevalence of sudden death in athletes; the efficacy, feasibility, and cost-effectiveness of population-based pre-participation cardiovascular screening; the key role of 12-lead ECG for identification of cardiovascular diseases such as cardiomyopathies and channelopathies at risk of sudden death during sports; and the potential of preventing fatal events. The main purpose of the consensus document is to reinforce the principle of the need for pre-participation medical clearance of all young athletes involved in organized sports programmes, on the basis of (i) the proven efficacy of systematic screening by 12-lead ECG (in addition to history and physical examination) to identify hypertrophic cardiomyopathy-the leading cause of sports-related sudden death-and to prevent athletic field fatalities; (ii) the potential screening ability in detecting other lethal cardiovascular diseases presenting with ECG abnormalities. The consensus document recommends the implementation of a common European screening protocol essentially based on 12-lead ECG.

Adolescent↗
PubMed2005

Regulatory mutations in transforming growth factor-beta3 gene cause arrhythmogenic right ventricular cardiomyopathy type 1.

OBJECTIVE: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetically heterogeneous disorder characterized by fibro-fatty replacement of the right ventricular myocardium, associated with high risk of sudden death. The objective of this study is to identify the gene involved in ARVD1, which has been elusive ever since its locus was mapped to chromosome 14q24.3. METHODS AND RESULTS: Mutation screening of the promoter and untranslated regions (UTRs) of the transforming growth factor-beta3 (TGFbeta3) gene was performed by direct sequencing of genomic DNA of one index case belonging to an ARVD1 family including 38 members in four generations. We detected a nucleotide substitution (c.-36G>A) in 5' UTR of TGFbeta3 gene, invariably associated with the typical ARVC clinical phenotype in the affected family members, according to the established diagnostic criteria. Investigation extended to 30 unrelated ARVC patients, performed by denaturing high-performance liquid chromatography (DHPLC), led to the identification of an additional mutation (c.1723C>T) in the 3' UTR of one proband. Neither nucleotide change was found in 300 control subjects. In vitro expression assays with constructs containing the mutations showed that mutated UTRs were twofold more active than wild-types. CONCLUSION: We identified TGFbeta3 as the disease gene involved in ARVD1. The identification of a novel ARVC gene will increase the power of the genetic screening for early diagnosis of asymptomatic carriers among relatives of ARVC patients.

3' Untranslated Regions↗
PubMed2005

Intracardiac echocardiography: gross anatomy and magnetic resonance correlations and validations.

PURPOSE: The feasibility and safety of intracardiac echocardiography (ICE) in humans, using low frequency transducers, and its excellent tissue contrast capabilities that enhances the differentiation of intracardiac structures have been previously demonstrated. However, correlations among ICE imaging and anatomic sections or magnetic resonance (MR) scan planes have never been described before. This study was designed to correlate a simplified ICE approach with the anatomy of the right atrium and great vessels obtained by serial post-mortem sections and cardiac MR images. METHODS: A stepwise approach to ICE, which is based on our experience on over 300 consecutive patients with interatrial communications, has been correlated with anatomic sections from pressure-perfused-fixed hearts and spin echo cardiac MR imaging. A 9F-9 MHz mechanical device was used to record four transverse and one longitudinal sections for an extensive evaluation of the intracardiac architecture. RESULTS: ICE transverse and longitudinal views allowed the detection of all the required information. Moreover, the anatomic sections and cardiac MR scan planes allowed validation of all the structures imaged by ICE. The potential clinical applications of the ICE technique are further discussed. CONCLUSION: This paper demonstrates the basic accuracy of this new imaging modality. Therefore, mechanical ICE might be considered an active investment in cardiac catheterization laboratories, specifically in the percutaneous interventional procedure setting, discovering a new route (let's see and treat) to sophisticated interventions. In this respect, there can be little doubt that the knowledge of cross-sectional mechanical ICE imaging provides the basis for understanding the heart anatomy.

Aortic Valve↗
PubMed2005

Juvenile sudden death in a family with polymorphic ventricular arrhythmias caused by a novel RyR2 gene mutation: evidence of specific morphological substrates.

We report on a family with a history of sudden death and effort-induced polymorphic ventricular arrhythmias. The index case was a 17-year-old boy who died suddenly and at postmortem had evidence of fibrofatty replacement in the right ventricular free wall, consistent with arrhythmogenic right ventricular cardiomyopathy, as well as calcium phosphate deposits within the myocytes. A molecular genetics investigation carried out in the paraffin-embedded myocardium of the subject and in blood samples of family members disclosed a missense mutation in exon 3 (230C-->T; A77V) of the cardiac ryanodine receptor type 2 gene. The carriers showed effort-induced polymorphic ventricular tachycardia in the setting of normal resting electrocardiogram and trivial echocardiographic abnormalities, consistent with catecholaminergic polymorphic ventricular tachycardia. The observation of both arrhythmogenic right ventricular cardiomyopathy type 2 and catecholaminergic polymorphic ventricular tachycardia in the same family suggests that the two entities might correspond to different degrees of phenotypic expression of the same disease. This experience underscores the importance of a precise autopsy diagnosis in the case of sudden cardiac death, including molecular genetics, and the mission of pathologists to guide further clinical investigation of family members.

Adolescent↗
PubMed2005

Is it time to include ion channel diseases among cardiomyopathies?

Heart muscle diseases are traditionally classified according to their peculiar pathophysiologic features such as "dilated," "hypertrophic," "restrictive," and "arrhythmogenic right ventricular" cardiomyopathy. The extraordinary advances accomplished in the last two decades in molecular genetics have allowed the identification of the genetic background of most of these conditions. According to the 1995 World Health Organization definition of cardiomyopathies as "diseases of the myocardium associated with cardiac dysfunction," they should include not only forms with hemodynamic dysfunction, but also conduction and rhythm disturbances. Arrhythmias are per se a sign of cardiac dysfunction and may reflect an underlying myocardial electrical disease with or without structural abnormalities as features. Nonstructural arrhythmogenic heart diseases include long and short QT syndromes, Brugada syndrome, Lènegre disease, and catecholaminergic polymorphic ventricular tachycardia. These conditions are defined as "channelopathies" because they are the consequence of cardiac ion channel gene mutations. Long and short QT syndromes are mostly caused by either sodium or potassium ion channel gene mutations; Brugada syndrome and Lènegre disease are both related to a defective sodium channel gene; and polymorphic ventricular tachycardia is the result of an abnormal ryanodine receptor regulating calcium release from the sarcoplasmic reticulum. These nonstructural inherited arrhythmic conditions should be regarded as cardiomyopathies because the myocyte is abnormal, although the heart is apparently intact. It is time for a new classification of cardiomyopathies taking into account the underlying gene mutations and the cellular level of expression of encoded proteins, thus distinguishing cytoskeleton (cytoskeletalopathies), desmosomal (desmosomalopathies), sarcomeric (sarcomyopathies), and ion channel (channelopathies) cardiomyopathies.

Arrhythmias, Cardiac↗
PubMed2005

Intermediate results of isolated mitral valve replacement with a Biocor porcine valve.

BACKGROUND: We analyzed the intermediate experience, survival, and prosthetic complications of patients who received the Biocor valve, a new-generation porcine valve, in the mitral position. METHODS: At the University of Padua, between May 1992 and January 2004, 154 consecutive patients (102 female and 52 male patients; mean age, 72.3 +/- 6 years; age range, 37-86 years) received 158 mitral Biocor prostheses (Biocor Industria e Pesguisa Ltda, Belo Horizonte, Brazil). Thirty-five percent of the patients had previous mitral operations, 24% had coronary artery bypass grafting, and 34.6% had other procedures. Median preoperative New York Heart Association class was III. Echocardiography was performed in 75% of the long-term survivors. Follow-up included 609.4 patient-years and was 100% complete, with a median time of 4 patient-years (range, 0.02-11.3 years). At 8 years, 20 (14%) of 142 operative survivors were still at risk. RESULTS: Early mortality was 13.6%. According to univariate analysis, New York Heart Association class III to IV, ejection fraction of less than 40%, urgency, male sex, and coronary artery bypass grafting were significant perioperative risk factors. Eight- and 10-year actuarial survival was 51.1% +/- 5.6% (40 deaths). Eight-year actuarial freedom from valve-related death, thromboembolism, anticoagulant-related hemorrhage, endocarditis, paravalvular leak, and valve-related complications were 85.2% +/- 5%, 85.7% +/- 4.4%, 92.6% +/- 3.7%, 94.1% +/- 3%, 91.8% +/- 3%, and 70.2% +/- 5.7%, respectively. Freedom from structural valve deterioration was 100%. Actual freedom from reoperation was 93.2% +/- 2.2%. By Doppler echocardiography, the peak and mean transprosthetic gradients were 15 +/- 5 mm Hg and 6.3 +/- 3 mm Hg, respectively (mean follow-up, 4.2 +/- 2.7 years). CONCLUSION: At intermediate follow-up, the Biocor prosthesis in the mitral position showed excellent results in terms of valve durability when compared with other second-generation tissue valves.

Adult↗
PubMed2005

Surgically treated primary cardiac tumors in early infancy and childhood.

OBJECTIVE: Primary heart tumors in childhood are rare and mostly benign. Surgical treatment is advocated when symptoms or hemodynamic impairment is present. MATERIALS AND METHODS: Between 1986 and 2003, 8 children (3 males and 5 females, age ranging 5 days to 6.7 years, median 78 days) with a clinical diagnosis of cardiac mass were treated with surgery. Diagnosis was made by prenatal echocardiography in 3 patients and by 2-dimensional Doppler echocardiography in 5 patients. RESULTS: Complete surgical excision of the cardiac mass was feasible in all but 1 patient who underwent orthotopic heart transplantation. Surgical pathology examination revealed myxoma in 2 patients, fibroma in 2 patients, rhabdomyoma in 2 patients (multiple in 1), hamartoma in 1 patient, and teratoma in 1 patient. One patient died of cerebral malignancy 38 months after cardiac transplantation. At a mean follow-up of 69.2 months (range 3-190 months), all the remaining patients are asymptomatic, with good ventricular function on 2-dimensional echocardiography and no signs of residual or recurrent tumor. CONCLUSION: Surgical excision of obstructive cardiac tumors in childhood is safely feasible. Heart transplantation may represent the only therapeutic option when the tumor extensively invades the ventricular walls. Although 2-dimensional echocardiography remains a reliable diagnostic tool, a definite diagnosis of tumor histotype requires a thorough histopathologic characterization.

Age Factors↗
PubMed2005

Surgical vs medical treatment for isolated internal carotid artery elongation with coiling or kinking in symptomatic patients: a prospective randomized clinical study.

BACKGROUND: Whether surgically correcting symptomatic carotid elongation with coiling or kinking in the absence of an atherosclerotic lesion of the carotid bifurcation (isolated elongation) is effective in preventing stroke remains a controversial issue. The hypothesis behind this study was that surgical correction of symptomatic isolated carotid elongation with coiling or kinking could yield better results, in terms of stroke prevention and freedom from late stroke or carotid occlusion, than medical treatment. METHODS: We conducted a prospective clinical study randomly assigning symptomatic patients with isolated carotid elongation to undergo either elective surgery or medical treatment, with surgery reserved for any new onset or worsening of symptoms. The follow-up ranged from 1 month to 10 years (median, 5.9; mean, 6.2 years) and was obtained for all patients. The study end points were perioperative (30-day) stroke and mortality, late stroke, and stroke-related death and late carotid occlusions. RESULTS: Ninety-two patients were randomly assigned for surgery and 90 for medical treatment. Overall, 139 carotid surgical corrections were performed in 129 patients. All 92 patients in the surgical arm had an elective operation; 10 of these patients later developed symptoms on the opposite side (7 hemispheric and 3 retinal transient ischemic attacks) and had contralateral internal carotid artery surgery. An additional 37 patients (41.1%) randomly assigned to medical treatment crossed over to the surgical group within a mean of 16.8 months after randomization due to new hemispheric symptoms or worsening nonhemispheric complaints. There were no perioperative strokes or deaths. The incidence of late hemispheric and retinal transient ischemic attacks was significantly lower in the surgical than in the medical group, respectively, 7.6% (7 of 92) vs 21.1% (19 of 90) (P = .01) and 3.2% (3 of 92) vs 12.2% (11 of 90) (P = .03). Late strokes, 2 (2.2%) of which were fatal, occurred only in the medical group (6 of 90, 6.6%; P = .01). Late carotid occlusions also developed only in the medical group (5 of 90, 5.5%; P = .02). All surgically treated carotid elongations were analyzed histologically and 78 (56.%) of 139 showed atypical and typical patterns of fibromuscular dysplasia. CONCLUSIONS: The overall results of this trial indicate that surgical correction of symptomatic isolated carotid elongations with coiling or kinking is better for stroke prevention than medical treatment.

Aged↗