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Marisa De Feo

Publications and source records attributed to Marisa De Feo.

At least 19 recordsLinked to original sources
PubMed2006

Echocardiographic anatomy of ascending aorta dilatation: correlations with aortic valve morphology and function.

BACKGROUND: Different anatomical forms of proximal aortic dilations associated with aortic valve disease can be distinguished by echocardiography. Differences in the anatomy could reflect different pathogeneses and need for different therapeutic approaches. The present study assessed the clinical features associated to each anatomical form, particularly focusing on the relations with valve morphology and function. METHODS: Trans-thoracic and trans-esophageal echocardiography reports of 552 adult patients (mean age 60.4+/-12.8 years; 379 male) with mild to severe proximal aorta dilation were reviewed. The relationships between the anatomy of aorta dilatation (distinguished into "root type" dilatation, with maximal enlargement at the sinuses, and "mid-ascending type", with maximal diameter at the mid-ascending tract) and aortic valve morphology (tricuspid/bicuspid) and function (normal/stenosis/regurgitation) were assessed. The relations with other clinico-echocardiographic variables were also tested in univariate and multivariate analysis. RESULTS: A "root type" dilatation was found in 4.9% tricuspid patients with stenosis, 32.3% with regurgitation, 22.5% with normal valve function (p=0.018). Dilatation prevailed at the mid-ascending tract in patients with bicuspid aortic valve, irrespective of valve function (stenotic: 92.9%, regurgitant: 87.9%, normal: 94.3%; p=0.23). Predominant root involvement was significantly more prevalent in male patients (24.8% versus 5.2% in females; p<0.001). In multivariate analysis, predominant aortic valve regurgitation (OR=1.83; p=0.028) independently predicted root site, while predominant aortic valve stenosis (OR=3.70; p=0.001), bicuspidity (OR=2.90; p=0.005) and female sex (OR=6.10; p<0.001) predicted mid-ascending site. CONCLUSIONS: Pathogenetical considerations arise from the evidence of preferential mid-ascending localization of bicuspid-associated aortic dilatations. This finding is consistent with previous studies on bicuspid valve models revealing a wall stress overload beyond the sino-tubular ridge.

Aorta↗
PubMed2006

High-risk heart grafts: effective preservation with Celsior solution.

Celsior solution has already proved effective in heart graft preservation because it reduces myocardial edema, prevents free radical damage, and limits calcium overload. The aim of this study was to evaluate the effectiveness of Celsior solution as myocardial protection in high-risk transplantation. Hospital charts and follow-up data of 200 consecutive heart recipients (162 males, 38 females, mean age 47.4 +/- 12.6 years) were reviewed. Patients were divided into two groups: group A (73 patients) included recipients of high-risk grafts (at least two of the following: age >45; female sex; high preretrieval inotropic support, viz. dobutamine or dopamine >10 microg/kg per minute and/or infusion of norepinephrine regardless of its dosage; size mismatch >20%; ischemia time >180 min) and group B (127 patients) included recipients of standard grafts. Quality of preservation was assessed through enzyme release, echocardiographic evaluation, the need for inotropic support or pacemaker, and histology of biopsy samples. Hospital and 1-year mortality were also evaluated. Comparisons between the two groups were made through univariate analysis. Study groups proved homogeneous as to recipient age, pretransplant cardiomyopathy, status at transplantation, mean panel reactive antibodies, and redo cardiac surgery. Hospital mortality was 8% (11% vs 6.3%, P = 0.18) while 1-year mortality reached 12% (15.1% vs 10.2%, P = 0.6) without significant difference between groups. Graft performance as described by the need for inotropic support and/or pacemaker as well as echocardiography (left and right ventricular ejection fraction) proved comparable. There were no significant differences as to histology findings and patterns of enzyme release. Celsior provides optimal myocardial preservation in both standard and high-risk procedures. Such advances help to enhance donor pool expansion.

Adolescent↗
PubMed2006

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↗
PubMed2006

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↗
PubMed2006

Rat carotid arteriotomy: c-myc is involved in negative remodelling and apoptosis.

OBJECTIVE: c-myc is the main proto-oncogene responsible for restenosis in cardiovascular surgery. The aim of our study was to evaluate the effects of c-myc antisense (AS) phosphorothioate oligodeoxynucleotides (ODNs) in the remodelling process induced by surgical carotid arteriotomy on an experimental rat model. METHODS: Fifty-five rats with carotid stenosis and apoptosis induced by arteriotomy were submitted to gene expression analysis 4 h after surgery, to TUNEL assay 48 h after surgery and to histological analysis 30 days later. RESULTS: AS ODNs induced a 60% decrease in target c-myc mRNA in injured carotid arteries compared to control sense and scrambled ODN-treated carotid arteries (P < 0.05). Histological evaluation revealed that stenosis stimulated by arteriotomy was mainly due to adventitial constrictive remodelling rather than to neointimal hyperplasia, observed only in a limited number of samples. Morphometric analysis showed that lumen area in c-myc AS ODN-treated carotid arteries was 35% greater than in control arteries (P < 0.05), whereas the media/lumen area ratio showed a 63% reduction in AS ODN-treated carotid arteries in comparison to control arteries (P < 0.05). Surgical injury affected the expression of apoptosis-related genes Bcl-2, Bax, Bcl-xL and Bcl-xS, inducing a mean 3.5-fold decrease in the Bcl-2/ Bax ratio and a 9-fold decrease in the Bcl-xL/S ratio 4 h after injury as compared with uninjured carotid arteries. TUNEL assay experiments revealed increased apoptosis in AS ODN-treated carotid arteries in comparison to control carotid arteries. CONCLUSIONS: c-myc AS ODNs reduce the negative remodelling induced by arteriotomy. The imbalance between proliferative stimulus represented by surgery and the c-myc mRNA decrease induced greater apoptosis in AS ODN-treated carotid arteries without further affecting mRNA levels of Bcl-2, Bax, Bcl-xL and Bcl-xS genes.

Analysis of Variance↗
PubMed2006

Spatial patterns of matrix protein expression in dilated ascending aorta with aortic regurgitation: congenital bicuspid valve versus Marfan's syndrome.

BACKGROUND AND AIM OF THE STUDY: Aortic wall stress has been shown to increase locally at the convex aspect of the ascending tract when axial root motion is increased, as occurs in aortic valve regurgitation. The study aim was to assess the expression of extracellular matrix (ECM) proteins involved in stress-induced vascular remodeling in the convexity and the concavity of dilated ascending aortas with aortic valve regurgitation. METHODS: Aortic wall specimens, harvested at the convexity and concavity of eight dilated ascending aortas with severe aortic valve regurgitation underwent morphometry, Western blot, RT-PCR and confocal immunohistochemistry. Five patients (group A) had congenital bicuspid aortic valve (BAV), and three (group B) had Marfan's syndrome. Specimens from the aorta of three multi-organ donors served as controls. RESULTS: At morphometry, medial degeneration was more severe in the convexity than in the concavity, especially in group A. Western blot, RT-PCR and immunohistochemistry disclosed an asymmetric pattern in the expression of some ECM proteins (laminin, tenascin, fibronectin). Fibronectin was increased in the convexity of both groups compared to controls at Western blot. Immunohistochemistry confirmed this pattern only in BAV. Higher levels of tenascin were found in the convexity in group A. The laminin content was greater in the concavity than in the convexity of both groups, but in group B the type of laminin was different, with the beta2 chain particularly expressed, and almost absent in non-Marfan patients. Type I and type III collagens were more markedly reduced in the convexity than in the concavity in BAV. In group B, type I collagen was decreased and type III increased, but without any significant difference between the two aspects of the aorta. CONCLUSION: A tissue remodeling response to valve disease-related wall stress may underlie aortic dilatation with BAV regurgitation. Although morphometry showed similar changes in Marfan aortas, molecular investigations differentiated this condition, qualitatively, from BAV.

Adult↗
PubMed2005

c-Myc antisense oligonucleotides preserve smooth muscle differentiation and reduce negative remodelling following rat carotid arteriotomy.

OBJECTIVES: The vascular biology of restenosis is complex and not fully understood, thus explaining the lack of effective therapy for its prevention in clinical settings. The role of c-Myc in arteriotomy-induced stenosis, smooth muscle cell (SMC) differentiation and apoptosis was investigated in rat carotids applying full phosphorothioate antisense (AS) oligonucleotides (ODNs). METHODS: Carotid arteries from WKY rats were submitted to arteriotomy and to local application of ODNs through pluronic gel. Apoptosis (deoxynucleotidyl transferase-mediated dUTP nick end-labelling), SMC differentiation (SM22 immunofluorescence) and vessel morphology and morphometry (image analysis) were determined 2, 5 and 30 days after injury, respectively. RESULTS: AS ODNs induced a 60% decrease of target c-Myc mRNA 4 h after surgery in comparison to control sense (S) and scrambled ODN-treated carotids (p < 0.05). A significant 37 and 50% decrease in SM22 protein in the media of S ODN-treated and untreated carotids was detected when compared to uninjured contralateral arteries (p < 0.05). This reduction in SM22 expression was prevented in AS ODN-treated carotids. Stenosis was mainly due to adventitial constrictive remodelling. Lumen area in AS ODN-treated carotids was 35% greater than in control arteries 30 days after surgery (p < 0.05). TUNEL assay revealed increased apoptosis in AS ODN-treated carotids (p < 0.05). CONCLUSIONS: c-Myc AS ODNs reduce arteriotomy-induced negative remodelling. This is accompanied by maintained SMC differentiation and greater apoptosis. The combination of reduced c-Myc-induced proliferation and increased apoptosis may thus underlie the less severe remodelling upon treatment with c-Myc mRNA AS ODN.

Animals↗
PubMed2005

Unstable angina and non-ST segment elevation: surgical revascularization with different strategies.

OBJECTIVE: Unstable angina/non-ST elevation myocardial infarction (UA/NSTEMI) still causes significant hospital morbidity and mortality. We evaluated whether surgical outcome can be modified by different myocardial protection strategies. METHODS: This was a prospective clinical study conducted in the cardiac surgery units of two university hospitals. Two hundred and sixty-two consecutive patients undergoing CABG for UA/NSTEMI between January 2002 and June 2004 were prospectively divided in three groups: 126 patients underwent on-pump CABG with antegrade blood cardioplegia (Group A); 67 underwent antegrade and retrograde blood cardioplegia (Group B); 69 off-pump CABG (Group C). Hospital outcome was analysed. Differences in outcome variables were detected with ANOVA; Tukey's multiple comparison test and Tamhane's T2 test were used when appropriate. RESULTS: Group A showed higher mortality (P=.001; P=.014 vs. Group B; P=.003 vs. Group C) and perioperative myocardial infarction (P=.001; P=.016 vs. Group B; P=.05 vs. Group C). Hospital stay was shorter in Group B and Group C, compared to Group A (P=.005; P=.043 and P=.05, respectively). Group A required higher doses of inotropes compared to Group B and Group C (P=.0001; P=.0001 and P=.03, respectively), whereas Group B and Group C did not require any inotropic support at all (P=.0001; P=.002 and P=.001 vs. Group A, respectively). Total morbidity was higher in Group A (P=.006; P=.007 vs. Group B; P=.005 vs. Group C). Wall motion score index recovered only in Group B (P=.0001) and Group C (P=.001). Troponin I was higher in Group A at 12 h (P=.0001; P<.001 vs. Group B and Group C), 24 (P=.0001; P=.001 vs. Group B and Group C), 48 (P=.0001; P=.001 vs. Group B, P=.002 vs. Group C) and 72 h (P=.0001; P=.004 vs. Group B; P=.05 vs. Group C). CONCLUSIONS: Isolated antegrade cardioplegia should be questioned in UA/NSTEMI. Outcome using off-pump revascularization was as good as that of combined antegrade and retrograde warm blood cardioplegia.

Aged↗
PubMed2005

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↗
PubMed2005

Determinants and prognosis of myocardial damage after coronary artery bypass grafting.

BACKGROUND: Myocardial infarction remains a devastating complication after coronary revascularization. Although electrocardiography (ECG) and echocardiography suggest transmural infarction, myocardial damage and the quality of myocardial protection are not recognized unless troponin I (TnI) is assessed. Determinants and prognosis of TnI elevation after coronary artery bypass grafting (CABG) were evaluated. METHODS: Data of 776 consecutive patients undergoing CABG between January 2002 and January 2004 were prospectively exposed to univariate and multivariate analysis. We evaluated the prognosis of patients with all the ECG, echocardiographic, and biochemical criteria for acute myocardial infarction and that of patients with only TnI elevation. Twelve-month follow-up survival and freedom from cardiac events (FCE) were accomplished. RESULTS: Troponin I greater than 3.1 mug/L at 12 hours was detected in 6.9% of the population, and correlated with lower in-hospital (p < 0.001) and follow-up survival (p = 0.00001), and lower FCE (p = 0.0009). Twenty-one (38.8%) of these fulfilled ECG-echocardiographic criteria (p = 0.05), demonstrating higher TnI values at 12 (p = 0.001), 24 (p = 0.01), 48 (p = 0.01), and 72 (p = 0.04) hours, prolonged ventilation time (p = 0.001), higher in hospital mortality (p = 0.003), lower follow-up survival (p = 0.023), and lower FCE (p = 0.0084). A EuroSCORE greater than 6, ongoing unstable angina, aortic cross-clamp time greater than 90 minutes, cardiopulmonary bypass time greater than 180 minutes, incomplete revascularization, and intraoperative intraaortic balloon pump were independent predictors of myocardial damage (MD) at multivariate analysis. Combined antegrade and retrograde cardioplegia and postoperative enoximone infusion were associated with a lower TnI elevation. CONCLUSIONS: Troponin I greater than 3.1 mug/L at 12 hours defines perioperative MD. Associated ECG-echocardiographic criteria indicate acute myocardial infarction and anticipate a worse outcome. Identification of predictors for MD is important to develop preventative strategies, as antegrade plus retrograde cardioplegia and enoximone infusion.

Aged↗
PubMed2005

Left ventricular mass regression after aortic valve replacement with 17-mm St Jude Medical mechanical prostheses in isolated aortic stenosis.

OBJECTIVE: The present study investigated the outcomes of aortic valve replacement with 17-mm mechanical prostheses in patients with isolated aortic stenosis. METHODS: Between January 1997 and January 2003, 35 patients (mean age, 63.4 +/- 17 years; median age, 70 years; age range, 16-84 years) underwent isolated aortic valve replacement with a 17-mm St Jude Medical Hemodynamic Plus (16 [45.7%] patients) or a St Jude Medical Regent prosthesis (19 [54.3%] patients). The paired Student t test or the paired Wilcoxon rank sum test were used to compare preoperative with follow-up echocardiographic measurements. RESULTS: Thirty-two (91.4%) patients were female, mean height was 154.4 +/- 8.3 cm, mean weight was 62.2 +/- 9.2 kg, and mean body surface area was 1.59 +/- 0.13 m 2 . The preoperative average New York Heart Association class was 2.8 +/- 0.8. The mean preoperative left ventricular mass index was 135.2 +/- 31 g/m 2 . Preoperative echocardiography showed an average gradient of 65.7 +/- 19.2 mm Hg (mean) and 103.6 +/- 30.7 mm Hg (peak) and a mean indexed effective orifice area of 0.40 +/- 0.1 cm 2 /m 2 . Echocardiographic follow-up time averaged 28.2 +/- 22.7 months (range, 13-72 months). Follow-up was 100% complete (1131.7 patient-months). Hospital mortality was 8.6% (3 patients). Actuarial 5-year survival was 94.7%. The mean postoperative New York Heart Association class was 1.13 +/- 0.34 ( P < .001), with 27 (87.1%) patients in class I and 4 patients in class II. A significant regression of the indexed left ventricular mass was found (postoperative mean value, 107.8 +/- 22.8 g/m 2 ; P < .0001), despite a mean indexed effective orifice area of 0.67 +/- 0.14 cm 2 /m 2 (median, 0.66 cm 2 /m 2 ). CONCLUSIONS: Selected patients with aortic stenosis can experience satisfactory clinical improvement and significant indexed left ventricular mass regression after aortic valve replacement with modern small-diameter bileaflet prostheses.

Adolescent↗
PubMed2005

Mitral mechanical replacement in young rheumatic women: analysis of long-term survival, valve-related complications, and pregnancy outcomes over a 3707-patient-year follow-up.

OBJECTIVE: A follow-up study was performed to assess long-term survival, valve-related complications, and pregnancy outcomes in young rheumatic women undergoing isolated mitral mechanical replacement. The influence of prosthetic type on outcomes was also investigated. METHODS: Between 1975 and 2003, 267 isolated mitral mechanical prostheses were implanted. Follow-up reached 3707.8 patient-years. RESULTS: Actuarial survival at 1, 5, 10, 15, 20, and 25 years was 97% +/- 0.01%, 90.4% +/- 0.017%, 85.3% +/- 0.023%, 82.3% +/- 0.025%, 71.7% +/- 0.036%, and 70.2% +/- 0.038%, respectively. At multivariate analysis, atrial fibrillation at follow-up was identified as an independent risk factor for late mortality, whereas left ventricular ejection fraction at 12 postoperative months proved to be a protective factor. Freedom from thromboembolism at 1, 5, 10, 15, 20, and 25 years was 98.1% +/- 0.01%, 94.1% +/- 0.015%, 89.1% +/- 0.021%, 85.9% +/- 0.025%, 81.1% +/- 0.031%, and 75.3% +/- 0.063%, respectively. Atrial fibrillation and Carbomedics device were significantly associated with an increase in thromboembolic events. Freedom from reoperation at 1, 5, 10, 15, 20, and 25 years was 99.2% +/- 0.005%, 95% +/- 0.014%, 91.6% +/- 0.018%, 88.6% +/- 0.022%, and 85.7% +/- 0.041%. Type of prosthesis (tilting disc) was identified as a predictor of reoperation. At the end of the study, 208 patients were still alive: 94.7% were in New York Heart Association class I or II. When receiving warfarin therapy, no patient undertaking pregnancy (n = 35) experienced adverse cardiac or valve-related events. Fetal events were significantly less frequent with a daily warfarin dose less than 5 mg. CONCLUSIONS: Mechanical devices provided excellent performance, safety, and durability. The prognostic role of left ventricular function and atrial fibrillation overwhelmed any differences that might exist between different prosthetic designs. Pregnancies entail virtually no maternal risk and predictable fetal complications.

Adolescent↗
PubMed2005

Different patterns of extracellular matrix protein expression in the convexity and the concavity of the dilated aorta with bicuspid aortic valve: preliminary results.

OBJECTIVE: This study aimed to assess extracellular matrix protein expression patterns at the convexity (right anterolateral wall) and the concavity of the dilated ascending aorta in patients with bicuspid aortic valve disease. METHODS: Aortic wall specimens were retrieved from the convexity and the concavity in 27 bicuspid aortic valve patients (12 with stenosis and 15 with regurgitation) and 6 heart donors (controls). Morphometry, immunohistochemistry, Western blot, and polymerase chain reaction were performed, focusing on matrix proteins involved in vascular remodeling. RESULTS: Type I and III collagens were significantly decreased in bicuspid-associated dilated aortas versus controls (P < .001), particularly at the convexity (P < .05 vs concavity). Expression of messenger RNA for collagens was lower than normal only in the regurgitant subgroup. At immunohistochemistry, proteins whose overproduction has been demonstrated in response to abnormal wall stress, such as tenascin and fibronectin, were more expressed in the convexity than in the concavity, especially in the stenosis subgroup. Tenascin, which is produced by smooth muscle cells in the synthetic phenotype, was nearly undetectable in controls. Fewer smooth muscle cells (stenosis, P = .017; regurgitation, P = .008) and more severe elastic fiber fragmentation (P = .029 and P < .001) were observed in the convexity versus the concavity. CONCLUSIONS: In bicuspid-associated aortic dilations, an asymmetric pattern of matrix protein expression was found that was consistent with the asymmetry in wall-stress distribution reported previously. Differences exist between patients with stenosis and those with regurgitation in terms of protein expression and content in the aortic wall. Further studies could clarify the relations between these findings and the pathogenesis of aortic dilatation in bicuspid aortic valve patients.

Aged↗
PubMed2005

Transthoracic Doppler echocardiography of mammary artery grafts to assess graft function.

BACKGROUND: Transthoracic Doppler echocardiography of internal mammary artery grafts (MAGs) has been tested by the supraclavicular approach, but little information is available about the parasternal approach. OBJECTIVE: To evaluate the usefulness of parasternal transthoracic Doppler echocardiography to assess the patency of left and right MAGs. PATIENTS AND METHODS: Forty-eight patients with previous MAGs were divided into two groups on the basis of coronary angiography: 42 patients had patent MAGs and six patients had severe MAG stenosis. Doppler echocardiography of MAGs was performed on all patients, both at baseline and after low-dose dipyridamole infusion. Systolic and diastolic time-velocity integrals and their ratios were obtained, and MAG flow reserve was calculated. RESULTS: Patients with patent MAGs had a predominant diastolic flow, while a prominent systolic pattern was found in the presence of MAG stenosis. In patients with stenosis, baseline Doppler analysis showed a lower diastolic peak velocity (DPV) (P<0.01), diastolic time-velocity integral (P<0.05), and diastolic and systolic time-velocity integral ratios (both P<0.005), and a reduced MAG flow reserve (P<0.001). In the overall population, when adjusting for clinical variables, a multilinear regression analyis underscored MAG flow reserve (beta=0.38, P<0.01) and baseline DPV (beta=0.29, P<0.05) as independent determinants of MAG stenosis (cumulative R2=0.25, P<0.005). CONCLUSIONS: Doppler echocardiographic evaluation of MAGs is a reliable, noninvasive tool to assess MAG patency and functional status of the vessel. MAG blood flow reserve and baseline DPV are independent determinants of MAG stenosis.

Aged↗
PubMed2005

Carotid arteriotomy induces different temporal gene expression profiles in normotensive and hypertensive rat strains.

Analysis of gene expression profiles in patients or in animal models affected by cardiovascular diseases may provide insight into therapeutic strategies. In this study, 3 rat strains, Wistar Kyoto (WKY), spontaneously hypertensive rats (SHR) and the Milan hypertensive rat strain (MHS), have been investigated to assess the influence of genetic background and/or of hypertension on gene expression in arteriotomy-injured carotid arteries (CAs). Expression profiles of genes, c-myc, AT1, AT2, ETA, ETB, Bcl-2, Bax and Bcl-X, were determined by reverse transcription-polymerase chain reaction (RT-PCR) in the acute phase, from 1 to 48 h, following CA arteriotomy. WKY, SHR and MHS show significant differences in gene expression profiles after CA arteriotomy. c-Myc mRNA is activated earlier and/or to a greater extent in hypertensive strains than in WKY (p<0.05). AT1 mRNA increases in WKY after injury, while it decreases in both SHR and MHS (p<0.05). AT2 shows the opposite behaviour, decreasing in WKY and increasing in hypertensive strains (p<0.05). ETA mRNA decreases in all strains although with different timing and levels, associated with a replacement by ETB mRNA (p<0.05). Bcl-2/Bax ratio gradually decreases in WKY, while it decreases only transiently in SHR and MHS 4 h after injury (p<0.05). Overall data indicate that therapeutic strategies for stenosis prevention should carefully consider the gene expression profile after injury, the genetic background, the kind of vascular trauma and the diseases affecting the animal model or the patient.

Animals↗
PubMed2005

Can harvesting techniques modify postoperative results of the radial artery conduit?

BACKGROUND: Inappropriate harvesting of arterial conduits can lead to severe postoperative complications. We analyzed clinical and functional results of patients undergoing radial artery (RA) harvesting by means of three techniques. METHODS: From January 2001 to January 2004 188 patients undergoing coronary artery bypass graft with RA were divided into three groups: harmonic scalpel was employed in 61 (RA1), electrocautery in 63 (RA2), Potts-scissors and clips in 64 (RA3) patients. Harvesting time, local complications, number of clips employed, graft flowmetry, postoperative troponin I, incidence of re-exploration for bleeding due to the graft were analyzed. RESULTS: RA1 and RA2 showed a lower harvesting time (RA1 16.2 +/- 8.4 vs RA3 41.4 +/- 7.7 min, p = 0.0001; RA2 21.1 +/- 10.4 min, p = 0.001). Postoperative hand paresthesia was detected in RA1 (5/61; 8.2%) and RA2 (5/63; 7.9%), but not in RA3 (p = 0.048 and p = 0.05, respectively). More clips were necessary in RA3 compared to RA2 (p = 0.04) or RA1 (p = 0.0001 vs RA3; p = 0.001 vs RA2). RA1 showed significant higher values of maximum flow (RA1 59.4 +/- 37.5 vs RA2 22.1 +/- 7.7 ml/min, p = 0.0001; vs RA3 31.3 +/- 12.0 ml/min, p = 0.001), mean flow (RA1 23.4 +/- 17.3 vs RA2 10.2 +/- 5.7 mi/min, p = 0.001; vs RA3 11.6 +/- 8.9 ml/min, p = 0.001), minimum flow (RA1 11.6 +/- 6.5 vs RA2 4.2 +/- 3.7 ml/min, p = 0.01; vs RA3 4.7 +/- 3.3, p = 0.03), and pulsatility index (RA1 0.9 +/- 0.8 vs RA2 2.1 +/- 1.3, p = 0.03; vs RA3 1.7 +/- 2.1, p = 0.04). Troponin I was significantly lower in RA1, compared to RA2 and RA3 at 12 hours (p = 0.01 and p = 0.03, respectively) and 24 hours (p = 0.05 and p = 0.045, respectively). No RA1 patient underwent re-exploration for bleeding compared to RA2 (p = 0.011) and RA3 (p = 0.02). CONCLUSIONS: RA harvesting with ultrasounds is fast, determines high flowmetry values, low enzyme release and rarely causes local complications.

Aged↗
PubMed2004

Mechanical heart valves: are two leaflets better than one?

OBJECTIVE: We sought to compare the long-term clinical outcomes of patients who underwent isolated aortic valve replacement with single-disc and bileaflet mechanical heart valves. METHODS: From May 1975 through October 2001, 590 single-disc valves (7 models) were used for isolated valve replacement, and from November 1980 through July 2002, 1283 bileaflet valves (10 models) were used for isolated valve replacement. Detailed follow-up was performed to a maximum of 27.4 and 21.9 years with a total of 6872 and 5811 patient-years for single-disc valves and bileaflet valves, respectively. Survival and valve-related events were analyzed. RESULTS: Single-disc valves were mainly implanted from 1975 through 1995, whereas bileaflet valves were mainly implanted from 1987 through 2002; thus the years of concurrent use were 1987 through 1995. The bileaflet valve had a significantly lower explantation rate, whereas the single-disc valve had a significantly lower thromboembolism rate. No significant differences were detected in early mortality, long-term survival, and other valve-related complications. When limiting the comparison to the concurrent period of 1987 through 1995, no significant difference was detected in survival or in any valve-related complication. CONCLUSION: Single-disc and bileaflet valves provide similar clinical performance. The predominant use of bileaflet valves is not based on clinical outcomes.

Adult↗