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C Nardi

Publications and source records attributed to C Nardi.

At least 19 recordsLinked to original sources
PubMed2006

Relationship between preclinical abnormalities of global and regional left ventricular function and insulin resistance in severe obesity: a Color Doppler Imaging Study.

BACKGROUND: The aim of this study was to evaluate the relationship between insulin resistance and preclinical abnormalities of the left ventricular structure and function detected in severe obesity by Color Doppler Myocardial Imaging (CDMI). Forty-eight consecutive severely obese patients (Group O) (11 males, 37 females, mean age 32.8+/-7 years) were enrolled. Forty-eight sex- and age-matched non-obese healthy subjects were also recruited as controls (Group C). All subjects underwent conventional 2D-Color Doppler echocardiography and CDMI. The homeostasis model assessment insulin resistance index (HOMA-IR) was used to assess insulin resistance results. Obese subjects had a greater left ventricular mass index (by height) (58.8+/-14 g/m(2.7)) than controls (37+/-8 g/m(2.7)) (P<0.0001), owing to compensation response to volume overload caused by a greater cardiac output (P<0.02). Preload reserve was increased in obese subjects, as demonstrated by a significant increase in left atrial dimension (P<0.0001). Obese patients had a slightly reduced LV diastolic function (transmitral E/A ratio: Group O, 1.1+/-0.8 vs Group C, 1.5 +/-0.5; P<0.002). Cardiac deformation assessed by regional myocardial systolic strain and strain rate (SR) values was significantly lower (abnormal) in obese patients than in controls, both at the septum and lateral wall level. These strain and SR abnormalities were significantly related to body mass index. In addition, the early phase of diastolic function, evaluated using SR, was compromised in obese patients (P<0.001). The HOMA-IR values in obese patients were significantly higher (3.09+/-1.6) than those determined in the control group (0.92+/-0.5) (P<0.0001). The HOMA-IR values, in the obese group, were significantly related to systolic strain and SR values sampled at the septum level (P<0.0001). CONCLUSION: In conclusion, this study has demonstrated that obese patients pointed out systolic structural and functional abnormalities at a preclinical stage, in particular through strain and SR analysis; on the other hand, those altered CDMI parameters well distinguish obese subjects as compared with the control group. Furthermore, another main finding of the study was that myocardial deformation (systolic strain) could have a correlation with insulin resistance level.

Adult↗
PubMed2005

Ultrastructural ciliary findings in nasal obstructive diseases.

Specific ultrastructural findings have widely been described in case of obstructive nasal diseases due to congenital defects. Ciliary impairment has in particular been observed as the main pathological feature in these conditions. In this study, nasal mucosal samples from different pathologies have been collected via the "brushing" technique and analysed by transmission electron microscopy. TEM analysis was focused on specific features, such as the numerical array of peripheral and central doublets of the cilium axoneme, including eventual microtubular disarrangement; partial or total loss of inner and/or outer dynein arms; defects of radial spokes and nexin links; disorientation of the ciliary axis in closely adjacent cilia, calculating the angle between the line crossing the central microtubular core and the horizontal ciliary axis and compound cilia (CC). Statistical comparison was carried out between study and control groups. A significant incidence of organic ciliary defects was found not only in patients with inflammatory processes, but mostly in those supposed to have a long-lasting nasal respiratory disease due to mechanical stenosis in relation to septum deviation and turbinate hypertrophy. Prevalence and percentage of compound cilia were instead more related to inflammatory conditions. The "brushing" technique can be considered an easy and reliable method for the assessment of the condition of the nasal mucosa. According to the findings derived from this study, mechanical nasal obstruction seems to cause major alterations on the nasal ciliary arrangement, thus determining a functional impairment on the whole nasal function.

Adult↗
PubMed2003

Effects of abciximab on microvascular integrity and left ventricular functional recovery in patients with acute infarction treated by primary coronary angioplasty.

AIM: To investigate the effect of abciximab on microvascular integrity and left ventricular (LV) functional recovery in patients with acute myocardial infarction (MI) treated by primary coronary angioplasty (PTCA). METHODS AND RESULTS: Thirty-one patients (27 males; age 39-76 years) with first, acute MI (<6 h after onset) were randomized to receive either abciximab+primary PTCA (n=17) or primary PTCA alone (n=14). Baseline characteristics of the two groups were similar. Myocardial reperfusion was studied shortly after PTCA by corrected TIMI frame count (cTFC) and intracoronary myocardial contrast echocardiography (MCE), after 48 h by intravenous MCE using intermittent, harmonic power Doppler, and after 1 month by intravenous MCE and 99 mTc-tetrofosmin SPECT. The patients treated with abciximab showed a shorter cTFC (23+/-4 vs 30+/-9 frames; P<0.05), a more preserved microvascular integrity shortly after PTCA (77% vs 55%; P<0.01), after 48 h (86% vs 50%; P<0.005) and at 1-month follow-up (86% vs 54% by MCE, P<0.001, and 68% vs 60% by SPECT, P<0.005) than patients treated with PTCA alone. Abciximab patients also showed a better recovery of LV function, as demonstrated by greater reduction in wall motion score index (1.4+/-0.3 vs 1.5+/-0.2; P<0.05) and increase in LV ejection fraction (53+/-7% vs 48+/-5%; P<0.001). CONCLUSIONS: Abciximab improves microvascular perfusion and LV functional recovery in primary PTCA.

Abciximab↗
PubMed2003

Coronary microcirculation into different models of left ventricular hypertrophy-hypertensive and athlete's heart: a contrast echocardiographic study.

The study was carried out in two different models of left ventricular hypertrophy: athlete's heart and essential arterial hypertension. Three groups of strictly age-matched males were studied: one group of 10 young adult untreated essential hypertensive patients (H), a second group of 10 athletes (A), and a group of 10 healthy individuals as controls (C). A Sonos 5500 echograph with S4 harmonic transducer was used with Levovist (ultrasonic tracer) before and after dipyridamole injection; digitised images of quantitative myocardial contrast echocardiography were collected with Power Harmonic Doppler. Angio images were analysed using dedicated PC software by placing a region-of-interest on the septum. Peak intensity, half-time (HT), the area under the curve of appearance and disappearance of microbubbles at 2/3 of PI, both in absolute and indexed values (/LVMi), were sampled. The per cent increase of PI after dipyridamole was significantly higher in C (+73%, P < 0.01) than in H (+31%) and in A (+33%) (P < 0.05). The area of appearance was significantly lower in H in comparison with C and A, both at rest and after vasodilatation. The disappearance area after dipyridamole was significantly higher in C and in A (+124%) than in H (+104%) (P < 0.05). Some hypothesis could be made: an impairment in the coronary microcirculatory function in hypertensive patients could be because of an in-crease in the arteriolar resistance. Angiogenesis and several different functional adaptations are the mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.

Adult↗
PubMed2002

Coronary microcirculation in essential hypertension: a quantitative myocardial contrast echocardiographic approach.

AIMS: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls. METHODS AND RESULTS: Two groups of strictly age-matched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles' appearance area was significantly lower in hypertensive patients than in controls (P<0.05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0.05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0.05). The microbubbles' disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0.05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole. CONCLUSION: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected.

Adult↗
PubMed2001

Dissection of atrial septum after mitral valve replacement.

We report a patient who presented with paraprosthetic leak complicated by dissection of the interatrial septum after mitral valve replacement. A review of the literature provides confirmation that only 3 cases have been previously reported of this potential, albeit extremely rare, complication of prosthetic mitral valve replacement. Prosthesis oversizing and improper mitral annular handling appeared to be the predisposing factors of this complication.

Echocardiography, Doppler, Color↗
PubMed2001

Hemodynamic performance of stented and stentless aortic bioprostheses.

BACKGROUND: This study compares the hemodynamic performance of stented and stentless bioprostheses used for aortic valve replacement in patients with aortic stenosis and small aortic root. METHODS: Between 1995 and 1998, 37 patients with a 21-mm aortic annulus (group 1) underwent aortic valve replacement with either a 21-mm Edwards Perimount or a 23-mm St. Jude Toronto bioprosthesis whereas 47 patients with a 23-mm aortic annulus (group 2) received either a 23-mm Medtronic Mosaic or a 25-mm Edwards Prima bioprosthesis. In each group mean and peak gradients, effective orifice area index, and left ventricular mass index were compared during follow-up. RESULTS: Group 1 patients showed a significant reduction of mean (p < 0.001) and peak gradients (p = 0.001) during follow-up, more evident for St. Jude Toronto versus Edwards Perimount (p = 0.02 and p = 0.05, respectively). Group 2 patients showed a significant reduction of mean and peak gradients (p < 0.001), more evident for Edwards Prima versus Medtronic Mosaic (p < 0.001 and p = 0.07, respectively). Effective orifice area index significantly increased only in group 1 (p = 0.005). Left ventricular mass index significantly decreased in all patients regardless of the type of valve (p < 0.001). Patients with Edwards Prima showed a trend to a higher regression of left ventricular mass index versus Medtronic Mosaic recipients (p = 0.07). CONCLUSIONS: After aortic valve replacement, stented and stentless bioprostheses exhibited similar results with a more evident hemodynamic improvement during follow-up in the stentless valves. Stented bioprostheses of new generation, however, may parallel the hemodynamic performance of stentless valves and appear to be a valid alternative for aortic valve replacement in elderly patients with a small aortic annulus.

Aged↗
PubMed2001

Hemodynamic assessment of the Medtronic Mosaic bioprosthesis in the aortic position.

BACKGROUND AND AIM OF THE STUDY: The Medtronic Mosaic bioprosthesis (MMB) is a newly developed tissue valve which incorporates several features such as a low-profile semi-flexible stent, zero-pressure tissue fixation, and anti-mineralization pretreatment with alpha-amino oleic acid aimed to improve hemodynamics and prevent structural deterioration. METHODS: Between November 1995 to June 1999, 62 patients underwent aortic valve replacement (AVR) with the MMB; 41 of these who reached the one-year follow up interval and who had isolated AVR without any concomitant procedure with size 23 mm and 25 mm MMB were evaluated by serial echocardiography after three, six and 12 months. RESULTS: For size 23 mm valves, mean and peak gradients were 12+/-3 and 21+/-6 mmHg at 3 months, 12+/-3 and 20+/-5 mmHg at 6 months, and 12+/-4 and 20+/-6 mmHg at 12 months. For size 25 mm valves, mean and peak gradients were 13+/-2 and 22+/-4 mmHg at 3 months, 12+/-3 and 21+/-5 mmHg at 6 months, and 12+/-4 and 22+/-6 mmHg at 12 months. In patients with 23 mm MMB, left ventricular mass index (LVMi) was reduced from 181+/-34 g/m2 before surgery to 158+/-32, 150+/-28 and 140+/-25 g/m2 at 3, 6 and 12 months after AVR (p <0.001); in patients with 25 mm MMB, LVMi was reduced from 182+/-28 g/m2 before surgery to 165+/-25, 156+/-24 and 146+/-19 g/m2 at 3, 6 and 12 months after AVR (p <0.001). CONCLUSION: Our results indicate that MMB is associated with low mean and peak gradients and significant reduction in LVMi throughout the postoperative period. Thus, the MMB appears to be an excellent cardiac valve substitute in elderly subjects who require AVR.

Adult↗
PubMed2000

Performance of 21-mm size perimount aortic bioprosthesis in the elderly.

BACKGROUND: Aortic valve replacement in elderly patients with a small aortic annulus may pose difficult problems in terms of prosthesis selection. We have evaluated the hemodynamic performance of the 21-mm Carpentier-Edwards Perimount bioprosthesis implanted in elderly patients. METHODS: From July 1996 to June 1998, 19 patients (17 women and 2 men, mean age 76+/-4 years and mean body surface area 1.73+/-0.13 m2), had aortic valve replacement with a 21-mm Carpentier-Edwards Perimount bioprosthesis. The hemodynamic performance of the valve was evaluated in 16 patients, who completed at least a 6-month follow-up interval, with transthoracic color-Doppler echocardiography with particular reference to peak and mean transprosthetic gradients, effective orifice area index, and regression of left ventricular mass index. RESULTS: There were no late deaths and no major postoperative complications. At a mean follow-up of 12+/-7 months, compared to discharge, all patients showed clinical improvement with a significant reduction of peak gradient (from 23+/-4 to 21+/-6 mm Hg, p = 0.04) and left ventricular mass index (from 181+/-23 to 153+/-20 g/m2; p<0.001), whereas mean gradient (from 13+/-3 to 13+/-4 mm Hg, p = not significant) and effective orifice area index (from 1.12+/-0.34 to 1.13+/-0.28 cm2/m2, p = not significant) remained substantially unchanged. CONCLUSIONS: The use of a 21-mm Carpentier-Edwards Perimount bioprosthesis is associated with low transprosthetic gradients and significant reduction in left ventricular hypertrophy after aortic valve replacement. The results of our study suggest that a 21-m Carpentier-Edwards Perimount bioprosthesis should be considered a valid option in elderly patients with aortic valve disease and a small aortic annulus.

Aged↗
PubMed2000

Mitral valve annuloplasty for degenerative disease: assessment of four different techniques.

BACKGROUND AND AIM OF THE STUDY: Mitral valve repair (MVR) is the treatment of choice in patients with degenerative valve disease. However, controversy persists as to whether mitral valve annuloplasty should always be included as part of the reconstructive procedure. METHODS: The records of 62 consecutive patients undergoing MVR for degenerative disease between January 1994 and December 1996 were reviewed. Four different annuloplasty techniques were associated with various MVR procedures: local posterior annuloplasty (group 1, n = 10), rigid Carpentier ring (group 2, n = 20), Duran ring (group 3, n = 17), and posterior annular plication with autologous pericardium (group 4, n = 15). The four patient groups were similar in terms of preoperative clinical and echocardiographic characteristics. Serial clinical and echocardiographic follow up was performed to assess functional status and stability of repair. RESULTS: There were no early or late deaths. Mean follow up in the entire patient series was 31 +/- 12 months. One patient in group 2 required reoperation 14 months after MVR. In all groups there was a significant improvement in NYHA functional class (from 2.7 +/- 0.6 to 0.9 +/- 0.5, p <0.001), with a reduction of left ventricular end-diastolic and end-systolic volumes (154 +/- 50 ml to 105 +/- 33 ml, p <0.001; and 64 +/- 23 ml to 52 +/- 22 ml, p <0.001). In patients of groups 2, 3 and 4, residual mitral incompetence at follow up (0.8 +/- 0.9 in group 2, 0.8 +/- 0.7 in group 3, and 0.2 +/- 0.6 in group 4) was not significantly different from discharge. However, in group 1, a higher degree of residual mitral regurgitation was present at discharge (0.9 +/- 0.6) with a trend to progress at follow up (1.6 +/- 0.5). CONCLUSION: In patients with degenerative mitral valve disease, MVR provides clinical and functional improvement. Techniques of stabilization of the entire posterior mitral annulus achieve better early and medium-term results, and should be always considered as part of MVR. Autologous pericardium appears to be an excellent annuloplasty material, though its apparent superiority over synthetic rings must be confirmed at longer follow up.

Cardiac Surgical Procedures↗
PubMed1999

Modulation of hepatitis C virus NS3 protease and helicase activities through the interaction with NS4A.

The hepatitis C virus nonstructural 3 protein (NS3) possesses a serine protease activity in the N-terminal one-third, whereas RNA-stimulated NTPase and helicase activities reside in the C-terminal portion. The serine protease activity is required for proteolytic processing at the NS3-NS4A, NS4A-NS4B, NS4B-NS5A, and NS5A-NS5B polyprotein cleavage sites. NS3 forms a complex with NS4A, a 54-residue polypeptide that was shown to act as an essential cofactor of the NS3 protease. We have expressed in Escherichia coli the NS3-NS4A precursor; cleavage at the junction between NS3 and NS4A occurs during expression in the bacteria cells, resulting in the formation of a soluble noncovalent complex with a sub-nanomolar dissociation constant. We have assessed the minimal ionic strength and detergent and glycerol concentrations required for maximal proteolytic activity and stability of the purified NS3-NS4A complex. Using a peptide substrate derived from the NS5A-NS5B junction, the catalytic efficiency (kcat/Km) of NS3-NS4A-associated protease under optimized conditions was 55 000 s-1 M-1, very similar to that measured with a recombinant complex purified from eukaryotic cells. Dissociation of the NS3-NS4A complex was found to be fully reversible. No helicase activity was exhibited by the purified NS3-NS4A complex, but NS3 was fully active as a helicase upon dissociation of NS4A. On the other hand, both basal and poly(U)-induced NTPase activity and ssRNA binding activity associated with the NS3-NS4A complex were very similar to those exhibited by NS3 alone. Therefore, NS4A appears to uncouple the ATPase/ssRNA binding and RNA unwinding activities associated with NS3.

Adenosine Triphosphatases↗
PubMed1999

Multiple determinants influence complex formation of the hepatitis C virus NS3 protease domain with its NS4A cofactor peptide.

The interaction of the hepatitis C virus (HCV) NS3 protease domain with its NS4A cofactor peptide (Pep4AK) was investigated at equilibrium and at pre-steady state under different physicochemical conditions. Equilibrium dissociation constants of the NS3-Pep4AK complex varied by several orders of magnitude depending on buffer additives. Glycerol, NaCl, detergents, and peptide substrates were found to stabilize this interaction. The extent of glycerol-induced stabilization varied in an HCV strain-dependent way with at least one determinant mapping to an NS3-NS4A interaction site. Conformational transitions affecting at least the first 18 amino acids of NS3 were the main energy barriers for both the association and the dissociation reactions of the complex. However, deletion of this N-terminal portion of the protease molecule only slightly influenced equilibrium dissociation constants determined under different physicochemical conditions. Limited proteolysis experiments coupled with mass spectrometric identification of cleavage fragments suggested a high degree of conformational flexibility affecting at least the first 21 residues of NS3. The accessibility of this region of the protease to limited chymotryptic digestion did not significantly change in any condition tested, whereas a significant reduction of chymotryptic cleavages within the NS3 core was detected under conditions of high NS3-Pep4AK complex affinity. We conclude the following: (1) The N-terminus of the NS3 protease that, according to the X-ray crystal structure, makes extensive contacts with the cofactor peptide is highly flexible in solution and contributes only marginally to the thermodynamic stability of the complex. (2) Affinity enhancement is accomplished by several factors through a general stabilization of the fold of the NS3 molecule.

Amino Acid Sequence↗
PubMed1999

The Edwards Prima stentless valve: hemodynamic performance at one year.

BACKGROUND: The Edwards Prima stentless valve (EPSV) is a porcine aortic root cylinder with resected coronary ostia, fixed in glutaraldehyde at low pressure. The purpose of this study was to evaluate the hemodynamic performance of the EPSV 1 year after aortic valve replacement. METHODS: From December 1994 to February 1996, 29 patients underwent aortic valve replacement with EPSV used in the subcoronary position (group 1, n = 23) or as a root replacement (group 2, n = 6). Hemodynamic performance of EPSV was assessed by two-dimensional Doppler echocardiography at 1 week, 6 months, and 1 year by calculating peak transprosthetic velocity, peak and mean gradients, effective orifice area, degree of aortic regurgitation, and regression of left ventricular hypertrophy. RESULTS: There were no operative deaths. One patient in group 2 died after 3 months at reoperation for endocarditis. In group 1 early mean gradient (25+/-5 mm Hg for 23 mm and 19+/-5 mm Hg for 25 mm) decreased at 6 months and 1 year in the 23-mm size (17+/-7 mm Hg and 15+/-4 mm Hg, p < 0.01) and at 1 year in the 25-mm size (14+/-4 mm Hg, p = 0.03) without modifications of the effective orifice area in both sizes. A significant reduction in left ventricular hypertrophy occurred at 6 months and 1 year in both sizes. In group 2 lower early gradients were recorded with subsequent improvement at follow-up; reduction in left ventricular hypertrophy occurred as well. CONCLUSIONS: The EPSV used in the subcoronary position has shown high early gradients, which partially regressed at 6 months, with further improvement at 1 year. Gradients are attributed to inward folding of the Dacron cloth at the right coronary ostium, being more evident in patients with aortic stenosis without dilatation of the aortic root and coronary ostia close to the annulus. In such patients a better early hemodynamic result can be obtained by using the EPSV as a root replacement.

Aged↗
PubMed1999

Selection of functional variants of the NS3-NS4A protease of hepatitis C virus by using chimeric sindbis viruses.

The NS3-NS4A serine protease of hepatitis C virus (HCV) mediates four specific cleavages of the viral polyprotein and its activity is considered essential for the biogenesis of the HCV replication machinery. Despite extensive biochemical and structural characterization, the analysis of natural variants of this enzyme has been limited by the lack of an efficient replication system for HCV in cultured cells. We have recently described the generation of chimeric HCV-Sindbis viruses whose propagation depends on the NS3-NS4A catalytic activity. NS3-NS4A gene sequences were fused to the gene coding for the Sindbis virus structural polyprotein in such a way that processing of the chimeric polyprotein, nucleocapsid assembly, and production of infectious viruses required NS3-NS4A-mediated proteolysis (G. Filocamo, L. Pacini, and G. Migliaccio, J. Virol. 71:1417-1427, 1997). Here we report the use of these chimeric viruses to select and characterize active variants of the NS3-NS4A protease. Our original chimeric viruses displayed a temperature-sensitive phenotype and formed lysis plaques much smaller than those formed by wild-type (wt) Sindbis virus. By serially passaging these chimeric viruses on BHK cells, we have selected virus variants which formed lysis plaques larger than those produced by their progenitors and produced NS3-NS4A proteins different in size and/or sequence from those of the original viruses. Characterization of the selected protease variants revealed that all of the mutated proteases still efficiently processed the chimeric polyprotein in infected cells and also cleaved an HCV substrate in vitro. One of the selected proteases was expressed in a bacterial system and showed a catalytic efficiency comparable to that of the wt recombinant protease.

Animals↗
PubMed1999

[Myocardial revascularization with arterial conduits: comparison of bilateral internal mammary artery and single internal mammary artery].

The use of bilateral internal mammary artery (BIMA) grafting for myocardial revascularization has been demonstrated to provide long-term benefits compared to revascularization using single left internal mammary artery (SIMA) and venous conduits. However, it is still controversial whether the use of BIMA is associated with a higher hospital mortality and morbidity. The present study retrospectively evaluated the possible advantages related to the use of BIMA at 3-year follow-up and whether the presence of operative risk factors in patients with BIMA could limit the application of the procedure in myocardial revascularization. We compared two groups of 100 patients matched for preoperative clinical characteristics, who underwent myocardial revascularization on the left coronary system with BIMA (93 males and 7 females, mean age 59 +/- 4 years) or with SIMA and venous conduits (86 males and 14 females, mean age 63 +/- 6 years). Hospital mortality rate was 2% in both groups, the use of BIMA being not a significant risk factor for hospital mortality and morbidity. The mean follow-up was 36 +/- 6 months for the BIMA group and 40 +/- 10 months for the SIMA group. At 3 years, there was no significant differences in the actuarial freedom from cardiac death (96 +/- 2% for BIMA vs 94 +/- 2% for SIMA patients), myocardial infarction (98 +/- 2 vs 97 +/- 2%), angina (93 +/- 2 vs 91 +/- 2%), symptomatic heart failure (92 +/- 3 vs 92 +/- 2%), coronary angioplasty/reoperation (96 +/- 2 vs 97 +/- 2% ), and total cardiac events (80 +/- 4 vs 76 +/- 4%). BIMA grafting was not an independent predictor of late cardiac events. In 66 patients who underwent a late angiographic or echo-Doppler study, the patency rate was 100% for the left mammary artery, 94% for the right mammary artery and 69% for venous conduits. In conclusion, myocardial revascularization with BIMA in situ is associated with low hospital mortality and morbidity, good clinical outcome and excellent patency rate at 3 years, with apparently no significant differences when compared to the use of SIMA and venous conduits. The low hospital mortality and morbidity and the satisfactory medium-term results in our opinion justify a more extensive use of BIMA in myocardial revascularization.

Aged↗
PubMed1999

[High-intensity transcranial Doppler signals in patients wearing heart valve prostheses: a prospective study].

BACKGROUND: Transcranial Doppler sonography (TCD) of the middle cerebral arteries in patients with prosthetic heart valves reveals high-intensity transient signals (HITS) and can detect asymptomatic cerebrovascular microemboli. Both the nature of the underlying embolic material (either gaseous or corpuscular) and its clinical significance remain uncertain. METHODS: Seventy-one patients undergoing heart valve replacement (n = 63) or repair (n = 8) from June 1996 to June 1998 were prospectively evaluated preoperatively and one week, 3 months and 12 months after valve replacement using TCD. At each follow-up interval, clinical assessment was aimed at detecting neurological events. Furthermore, continuous echo-Doppler study of the carotid arteries and TCD of the middle cerebral arteries for a 30-minute period during each following visit was carried out. RESULTS: No HITS were recorded preoperatively in any patient. At one week, HITS were detected in 25 patients (35%): 22 (65%) of these had received a mechanical prosthesis and three (10%) a bioprosthesis. No HITS were recorded in patients with mitral repair. HITS were subsequently detected only in patients with mechanical prosthesis with a positive TCD at one week, the mean number of HITS per patient being 7 +/- 18 at 3 months and 8 +/- 24 at 12 months. No neurological symptoms were evident in any patients during the postoperative evaluation. Multivariate analysis showed mechanical prosthetic valve to be the only independent predictive risk factor for HITS development. CONCLUSIONS: The role of a mechanical prosthetic valve as a risk factor in the pathogenesis of HITS appears evident. However, HITS appear to be unrelated to possible postoperative neurological events. TCD could have more specific clinical applications if associated with methods that would make it possible to ascertain the nature of various embolic materials.

Aged↗
PubMed1999

Recurrent myxoma of the left ventricle. Case report and review of the literature.

A 29-year-old female was found to have a left ventricular mass while in the 14th week of gestation. Seven years earlier she had undergone removal of a left ventricular myxoma. At re-operation, after elective interruption of pregnancy, a recurrent left ventricular myxoma was successfully excised. According to a review of the literature recurrence of an isolated, localized left ventricular myxoma has not been previously reported.

Adult↗