Effects of the sander bite jumping appliance in patients with class ii malocclusion before growth peak.

Sander bite jumping appliance (BJA) is a functional appliance used to correct Class II malocclusion in growing patients. The aim of this study was to identify the dento-skeletal effects in patients treated with BJA before growth peak and to compare these effects with the ones obtained in a similar group treated with the Andresen activator (AA). Twenty subjects with class II relationship of the skeletal bases and cervical vertebrae maturation stage 1 or 2 were enrolled in the study and treated with BJA. This group were compared to 14 subjects treated with AA. Cephalometric analyses were carried out using landmarks derived from the analyses of Pancherz, Ricketts, Tweed and Steiner. After treatment with BJA Pg/OLp increase was 7.40±3.81 mm (P<0.001); Pg/OLp+Co/OLp significantly heightened from T0 to T1 (T0: 82.20±4.65 mm vs T1: 89.62±4.27, P<0.001). Overjet (is/OLp - ii/OLp) significantly decreased from T0 to T1 (T0: 7.40±2.31 mm vs T1: 3.05±1.34 mm, P<0.001). Molar relationship improved passing from 1.46±1.68 mm at T0 to -3.56±2.04 mm at T1 (P<0.001). No statistically significant differences were found between BJA and AA groups at T0 and T1. BJA treatment determined a Class II malocclusion correction in all patients. The correction of molar relationship was mainly due to the increase in mandibular length; the correction of the overjet was due to the increase in mandibular length, to the slight pro-inclination of the lower incisors and the mild retro-inclination of the upper incisors. No significant differences were found in effectiveness between BJA and AA.

Evaluation of bacterial flora composition on teeth and periodontal tissues in patients in treatment with rapid palatal expander.

Patients in treatment with rapid palatal expander (RPE) require professional assistance and more meticulous instructions on oral hygiene, since this appliance predisposes to gingivitis and caries. The aim of this work is to analyse the variability of the oral microbial flora found in patients in treatment with RPE with occlusal acrylic splint. It was also investigated whether the association of an antimicrobial mouthwash was useful during orthodontic treatment or whether regular and specific home oral hygiene manoeuvres were sufficient to maintain a good plaque control. The last goal was to highlight which of the different mouthwashes was the most effective in reducing the bacterial load. The patients were divided into 3 test groups and each one of them had a different mouthwash (chlorhexidine and sodium fluoride, fluorine, essential oils) randomly assigned. There was also a control group. Plaque samples were analysed through cultural analysis and PCR from T0 to T4 (8 months). Chlorhexidine mouthwash reduces the bacterial count by 96.08%, the fluorine by 94.50% and the essential oils by 95.74%. The results of the three mouthwashes are superimposable and although chlorhexidine gives the highest rate of bacteria reduction, its side effects lead the authors to prefer the essential oils.

Short-term in vivo evaluation of cellular DNA damage induced by fixed orthodontic appliances.

Metal ions accumulate inside the epithelial cells of the oral mucosa and damage the DNA. The aim of this study was to analyze whether DNA damage and/or apoptosis also occurs after a short-term exposure to the metals of fixed orthodontic appliances. 23 subjects were enrolled in the test group and 8 patients in the control group. Analyses performed on samples of oral mucosa were cell count, cellular viability, quantification of intracellular metal concentration, comet and micronuclei tests and quantification of intracellular Glutathione (GSH). The obtained results indicated that orthodontic appliances release metal ions, especially chromium, that cause inflammatory processes leading to DNA damages. These phenomenon are visible only after 30 days from application of fixed orthodontic appliances.

Medidas comparativas do padrão morfométrico e perfil energético de éguas crioulas no terço final da gestação, com diferentes escores corporais / Comparative measurements of the morphometric pattern and energy profile of crioula mares in the final third of gestation, with different body condition scores

O objetivo deste estudo é comparar e descrever medidas morfométricas e perfil energético de éguas da raça Crioula no terço final da gestação. Foram utilizadas vinte éguas gestantes, divididas em 2 grupos conforme o escore corporal (BCS); o GrN (n=10), grupo de éguas com BCS 5 ou moderado, e GrO (n=10), grupo de éguas obesas ou BCS 9, analisadas conforme o mês de gestação (8º, 9º, 10º e 11º). Foram realizadas coletas de sangue e avaliações morfométricas mensais do peso corporal (PC), perímetro torácico (PT), perímetro abdominal (PA), altura da crista do pescoço (AC), espessura de gordura subcutânea na base da cauda (EGBC) e espessura de gordura retroperitoneal (EGRP). Para avaliar o perfil energético, foram mensurados os níveis séricos de triglicerídeos (TAG), ácidos graxos não esterificados (NEFA), Leptina (LEP) e Adiponectina. Os resultados das mensurações analisadas demonstraram no GrN incremento (P<0,05) nas variáveis PC, PT, PA e NEFA do 8º para o 9º mês de gestação. Porém, na variável EGBC, o aumento (P<0,01) foi observado entre o 8º e o 11º mês avaliado. No GrO, o PA demonstrou incremento (P<0,01) entre o 8º e o 11º mês de gestação, e a LEP apresentou aumento (P<0,05) entre o 10º e o 11º mês. Quando os dois grupos foram comparados, as variáveis PC, PT, EGBC e EGRP apresentaram diferença (P<0,05) em todos os meses avaliados. Na análise de correlação, o BCS associou-se com o PC (r=0,691; P<0,0001), PT (r=0,705; P<0,0001), EGBC (r=0,701; P<0,0001), EGRP (r=0,627; P<0,0001), níveis séricos de LEP (r=0,426; P<0,0001) e Adiponectina (r=0,217; P<0,05). Dessa forma, pode-se afirmar que a gordura corporal aumentou progressivamente nas éguas do GrN, diferentemente do observado no GrO. Através dos métodos utilizados neste trabalho, torna-se possível a avaliação prática da morfometria das éguas da raça Crioula no terço final da gestação, possibilitando de forma objetiva a identificação de indivíduos obesos.

The aim of this study was to compare and describe morphometric measurements and energy profile of the Crioula breed mares at the end of gestation. Twenty pregnant mares were used and separated into 2 groups according to body condition score (BCS). The GrN (n= 10) group of mares with BCS 5 or moderate and GrO (n = 10) group of obese mares or BCS 9 were analyzed according to the month of pregnancy (8th, 9th, 10th and 11th). Blood samples and monthly morphometric evaluation were performed for body weight (PC), heart girth (PT), waist circumference (PA), height of the crest of the neck (AC), thickness subcutaneous fat on the base of the tail (EGBC) and retroperitoneal (EGRP). To evaluate the energy profile serum levels of triglycerides (TAG), non-esterified fatty acids (NEFA), leptin (LEP) and adiponectin were measured. The results of the analyzed measurements showed an increase in GrN (P<0.05) in the PC, PT, PA and NEFA variables between the 8th and 9th month of pregnancy. Although there was an increase (P<0.01) between the 8th and 11th month of pregnancy in the EGBC variable, in GrO the PA was increased (P<0.01) between the 8th and 11th month of pregnancy and the LEP showed an increase (P<0.05) between the 10th and 11th month. When both groups were compared, the variables PC, PT, EGBC and EGRP showed differences (P<0.05) in all months evaluated. In the correlation the BCS was associated with PC (r=0.691, P<0.0001), PT (r=0.705, P<0.0001), EGBC (r=0.701, P<0.0001), EGRP (r=0.627, P<0.0001), serum leptin levels (r=0.426, P<0.0001) and adiponectin (r=0.217, P<0.05). Thus, it can be stated that the body fat increased progressively in mares GrN, different from that observed in GrO. Therefore, by the methods used in this study, the morphometry practical evaluation of the Crioula breed mares in the last third of gestation became possible, allowing an objective way to identify obese individuals.

Optimal rectification in the ultrastrong coupling regime.

We study the effect of ultrastrong coupling on the transport of heat. In particular, we present a condition for optimal rectification, i.e., flow of heat in one direction and complete isolation in the opposite direction. We show that the strong-coupling formalism is necessary for correctly describing heat flow in a wide range of parameters, including moderate to low couplings. We present a situation in which the strong-coupling formalism predicts optimal rectification whereas the phenomenological approach predicts no heat flow in any direction, for the same parameter values.

Improved tretinoin photostability in a topical nanomedicine replacing original liquid suspension with spray-dried powder with no loss of effectiveness.

OBJECTIVE: The use of spray-dried powders containing tretinoin-loaded nanocapsules instead of the original liquid suspension, aimed at the preparation of dermatological nanomedicines with improved photostability, was investigated. METHODS: Powders were prepared using lactose as a drying adjuvant. Hydrogels were prepared using two approaches: dispersing Carbopol Ultrez 10 in an aqueous redispersion of the powder or incorporating the powder in previously formed hydrogels. RESULTS AND DISCUSSION: The photodegradation of tretinoin in hydrogels prepared with the powders showed similar half-life times (around 19.5 h) compared to preparations with the original liquid nanocapsules (20.7 ± 1.4 h), regardless of the preparation approach. In addition, the topical nanomedicines prepared with the spray-dried powders presented a significant improvement in tretinoin photostability compared to the formulation containing the non-encapsulated drug. CONCLUSION: This study verified that the addition of the spray-dried powders containing tretinoin-loaded lipid-core nanocapsules to hydrogels did not influence the photoprotection of the drug compared with the preparation procedure using the original liquid suspension.

Spray-dried powders containing tretinoin-loaded engineered lipid-core nanocapsules: development and photostability study.

The influence of the spray-drying process on the ability of engineered lipid-core nanocapsules to protect tretinoin against UV degradation was evaluated. This approach represents a technological alternative to improve the microbiological stability, storage and transport properties of such formulations. Tretinoin-loaded lipid-core nanocapsules or tretinoin-loaded nanoemulsion were dispersed in lactose (10% w/v) and fed in the spray-drier to obtain a solid product (spray-dried powder containing tretinoin-loaded nanocapsules or nanoemulsion--SD-TTN-NCL or SD-TTN-NE, respectively). SD-TTN-NE showed a lower (p < or = 0.05) percentage of encapsulation (89 +/- 1%) compared to SD-TTN-NCL (94 +/- 2%). Redispersed SD-TTN-NCL and SD-TTN-NE showed z-average sizes of 204 +/- 2 nm and 251 +/- 9 nm, which were close to those of the original suspensions (220 +/- 3 nm and 239 +/- 14 nm, respectively). Similar percentage of photodegradation were determined for tretinoin loaded in nanocapsules (26.15 +/- 4.34%) or in the respective redispersed spray-dried powder (28.73 +/- 6.19 min) after 60 min of UVA radiation exposure (p > 0.05). Our experimental design showed for the first time that spray-dried lipid-core nanocapsules are able to protect tretinoin against UVA radiation, suggesting that the drying process did not alter the supramolecular structure of the lipid-core nanocapsules. Such powders are potential intermediate products for the development of nanomedicines containing tretinoin.

Energy transfer dynamics and thermalization of two oscillators interacting via chaos.

We consider the classical dynamics of two particles moving in harmonic potential wells and interacting with the same external environment HE, consisting of N noninteracting chaotic systems. The parameters are set so that when either particle is separately placed in contact with the environment, a dissipative behavior is observed. When both particles are simultaneously in contact with HE an indirect coupling between them is observed only if the particles are in near-resonance. We study the equilibrium properties of the system considering ensemble averages for the case N=1 and single trajectory dynamics for N large. In both cases, the particles and the environment reach an equilibrium configuration at long times, but only for large N can a temperature be assigned to the system.

Energy dissipation via coupling with a finite chaotic environment.

We study the flow of energy between a harmonic oscillator (HO) and an external environment consisting of N two-degrees-of-freedom nonlinear oscillators, ranging from integrable to chaotic according to a control parameter. The coupling between the HO and the environment is bilinear in the coordinates and scales with system size as 1/√N. We study the conditions for energy dissipation and thermalization as a function of N and of the dynamical regime of the nonlinear oscillators. The study is classical and based on a single realization of the dynamics, as opposed to ensemble averages over many realizations. We find that dissipation occurs in the chaotic regime for fairly small values of N, leading to the thermalization of the HO and the environment in a Boltzmann distribution of energies for a well-defined temperature. We develop a simple analytical treatment, based on the linear response theory, that justifies the coupling scaling and reproduces the numerical simulations when the environment is in the chaotic regime.

Lipid-core nanocapsules as a nanomedicine for parenteral administration of tretinoin: development and in vitro antitumor activity on human myeloid leukaemia cells.

Tretinoin-loaded conventional nanocapsules have showed a significant protection of this drug against UVC radiation. However, this formulation presents a limited stability on storage. We hypothesized that the association of tretinoin to lipid-core nanocapsules could increase the physicochemical stability of such formulations, focusing on the development of a reliable nanomedicine for parenteral administration. However, this advantage should still be accompanied by the known photoprotective effect of conventional polymeric nanocapsules against the exposure of tretinoin to UV radiation. Results showed that tretinoin-loaded lipid-core nanocapsules improved the physicochemical stability of formulations under storage, without changing their ability to protect tretinoin either against UVA or UVC radiation. In addition, the effect of nanoencapsulation on the antiproliferative and differentiation properties of tretinoin was studied on human myeloid leukemia cells (HL60 cells) showing that tretinoin-loaded lipid-core nanocapsules presents a longer antitumor efficiency compared to the free tretinoin. These results allow us to propose the current formulation (tretinoin-loaded lipid-core nanocapsules) as a promising parenteral nanomedicine for the treatment of acute promyelocytic leukaemia.

Hydrogel containing dexamethasone-loaded nanocapsules for cutaneous administration: preparation, characterization, and in vitro drug release study.

CONTEXT: Our group previously reported the development of dexamethasone-loaded polymeric nanocapsules as an alternative for topical dermatological treatments. OBJECTIVE: Our study aimed to prepare and characterize a hydrogel containing this system to improve the effectiveness of the glucocorticoid for cutaneous disorders. METHODS: For the antiproliferative activity assay, a dexamethasone solution and D-NC were tested on Allium cepa root meristem model. D-NC were prepared by the interfacial deposition of preformed polymer. Hydrogels were prepared using Carbopol Ultrez 10 NF, as polymer, and characterized according to the following characteristics: pH, drug content, spreadability, viscosity, and in vitro drug release. RESULTS AND DISCUSSION: Nanocapsules showed mean particle size and zeta potential of 201 +/- 6 and -5.73 +/- 0.42 nm, respectively. They demonstrated a lower mitotic index (4.62%) compared to free dexamethasone (8.60%). Semisolid formulations presented acidic pH values and adequate drug content (between 5.4% and 6.1% and 100% and 105%, respectively). The presence of nanocapsules in hydrogels led to a decrease in their spreadability factor. Intact nanoparticles were demonstrated by TEM as well as by dynamic light scattering (mean particle size < 300 nm). In vitro studies showed a controlled dexamethasone release from hydrogels containing the drug associated to the nanocapsules following the Higuchi's squared root model (k = 20.21 +/- 2.96 mg/cm(2)/h(1/2)) compared to the hydrogels containing the free drug (k = 26.65 +/- 2.09 mg/cm(2)/h(1/2)). CONCLUSION: Taking all these results together, the hydrogel containing D-NC represent a promising approach to treat antiproliferative-related dermatological disorders.

Serum lipoprotein profile and APOE genotype in Alzheimer's disease.

Alterations in cholesterol homeostasis are associated with Alzheimer's disease (AD). The role played by specific fractions of serum lipoproteins in modifying the risk of AD, and the interaction with APOE genotype has not yet been investigated. We studied serum lipoprotein profiles using a gradient-density ultracentrifugation method in a cohort of late-onset sporadic AD patients without cerebrovascular lesions and in healthy elderly subjects. In the AD group the lipoprotein cholesterol distribution showed an increase in LDL cholesterol, reaching a significant difference with respect to controls in the LDL sub-fractions representing the transition between small dense-LDL (fraction 11, p = 0.04) and normal-density LDL particles (fraction 12, p = 0.03). APOE genotype and LDL cholesterol were independently associated with AD. The mean concentration of LDL in fractions 11 and 12 increased the risk of developing AD (p = 0.01 and p = 0.025, respectively). These results confirm that an alteration of cholesterol homeostasis is associated with AD and that serum concentrations of LDL cholesterol are higher in AD patients without cerebrovascular pathology than in elderly normal subjects. The presence of the APOE epsilon4+ allele is a risk factor for AD independent of increased serum cholesterol or a modification of other vascular risk factors. Increased levels of specific sub-fractions of LDL cholesterol may be associated with increased risk of AD.

Quantifying the relevance of different mediators in the human immune cell network.

MOTIVATION: Immune cells coordinate their efforts for the correct and efficient functioning of the immune system (IS). Each cell type plays a distinct role and communicates with other cell types through mediators such as cytokines, chemokines and hormones, among others, that are crucial for the functioning of the IS and its fine tuning. Nevertheless, a quantitative analysis of the topological properties of an immunological network involving this complex interchange of mediators among immune cells is still lacking. RESULTS: Here we present a method for quantifying the relevance of different mediators in the immune network, which exploits a definition of centrality based on the concept of efficient communication. The analysis, applied to the human IS, indicates that its mediators differ significantly in their network relevance. We found that cytokines involved in innate immunity and inflammation and some hormones rank highest in the network, revealing that the most prominent mediators of the IS are molecules involved in these ancestral types of defence mechanisms which are highly integrated with the adaptive immune response, and at the interplay among the nervous, the endocrine and the immune systems. CONTACT: claudio.franceschi@unibo.it.

Efficient behavior of small-world networks.

We introduce the concept of efficiency of a network as a measure of how efficiently it exchanges information. By using this simple measure, small-world networks are seen as systems that are both globally and locally efficient. This gives a clear physical meaning to the concept of "small world," and also a precise quantitative analysis of both weighted and unweighted networks. We study neural networks and man-made communication and transportation systems and we show that the underlying general principle of their construction is in fact a small-world principle of high efficiency.

[Heart rupture in acute myocardial infarct: the advantages of using M-2D color Doppler echocardiography in a coronary intensive therapy unit]. / Rottura di cuore nell'infarto acuto del miocardio: vantaggi dell'uso dell'ecocardiografia M-2D color Doppler in unità di terapia intensiva coronarica.

BACKGROUND: Free-wall rupture of the heart is the second most common cause of death in acute myocardial infarction (AMI), following pump failure. Acute rupture is more common and rapidly fatal, while subacute rupture, which accounts for about 30% of total cases of mortality in AMI, can be diagnosed early by clinical signs with the support of echocardiography in coronary intensive care units. METHODS: From March 1996 to December 1997, 293 patients diagnosed with acute myocardial infarction were admitted to the coronary intensive care unit of our hospital. Of these patients, 71 (23.8%) were treated with thrombolysis within 6 hours of onset of symptoms. All patients were observed daily with M-2D color Doppler echocardiography and in the event of renewed chest pain, electrocardiogram changes, abrupt hypotension, syncope or clinical signs of low output syndrome. RESULTS: We observed 11 cases (3.8%) of free-wall rupture of the heart in acute myocardial infarction with echocardiography, 6 females and 5 males, with a mean age of 74.2 +/- 7.8 years (min. 56-max 84), none of whom had prior AMI. Six of them received thrombolytic therapy, six were hypertensive (54.5%) and three were diabetics (27.2%). Surgical repair was performed in two patients with subacute rupture, but one died a few days later. The echocardiography data at bedside for diagnosis of cardiac rupture were confirmed in 5 patients with autopsy and intraoperatively in two of them. CONCLUSIONS: Routine use of echocardiography in coronary intensive care units allows prompt diagnosis of cardiac rupture in acute myocardial infarction, and in the event of subacute rupture it can accelerate surgical decision-making.

Laparoscopic colorectal procedures: a multicenter Brazilian experience.

An evaluation of the results of the Brazilian experience in colorectal laparoscopic procedures in a multicenter prospective protocol done by the Brazilian Society of Colo-Proctology is presented. From December 1991 to August 1998, 1,161 patients (583 men and 578 women; mean age, 49.8 years), were operated on laparoscopically. Most of the procedures (40.5%) were for cancer, and the most common procedure was anterior resection (22.5%). The mean operative time was 189 minutes (3.1 hours). There were 42 (3.6%) perioperative complications; visceral injuries were the most common (1.4%). Conversions occurred in 122 (10.5%) cases. There were 148 (12.7%) postoperative complications; wound infections were the most common (5.2%). A liquid diet was started at a mean time of 1.4 days after the operation, and the mean hospitalization period was 6.4 days.

[Environmental lead exposure in the Venetian population from 1976-1992]. / Esposizione ambientale al piombo nella popolazione dell'area veneziana dal 1976 al 1992.

Blood lead levels observed in the general population of Venice and the surrounding area are reported for the period between 1976 and 1992. A time dependent decrease of blood lead levels is evident and parallels the step wise decrease of lead levels in gasoline which took place between 1981 and 1991. The observed lowering time trend of blood lead levels could possibly be ascribed, perhaps not negligibly, to technological improvements, the development of new analytical procedures and the continuous practice of quality control.

[Percutaneous mitral valvuloplasty in mitral restinosis after surgical commissurotomy]. / Valvuloplastica mitralica percutanea nella restenosi mitralica dopo commissurotomia chirurgica.

UNLABELLED: The frequency of mitral restenosis after surgical commissurotomy has been estimated between 10 and 30% up to 10 years and 85% up to 28 years. Aim of this study was to analyze the results of balloon mitral valvuloplasty (BMV) in a series of patients with previous surgical commissurotomy. METHODS: Between December 1988 and December 1995 432 patients underwent BMV. Of these patients, 30 (6.9%; 10 men, 20 women, aged 53 +/- 12 years) had recurrent mitral stenosis after surgical commissurotomy. Contraindications to BMV were the evidence of left atrial thrombi at transesophageal echocardiography and/or of mitral insufficiency > 2+/4+. The Inoue's single balloon catheter was used for all the procedures. RESULTS: BMV resulted in a decrease in mean mitral gradient from 12.6 +/- 3.8 to 6.1 +/- 2.9 mmHg, and an increase in mitral valve area from 1.03 +/- 0.19 cm2 to 1.95 +/- 0.40 cm2. A mitral insufficiency > or = 3+/4+ occurred in 4/30 BMV (13%). At follow-up (mean 27 +/- 18 months) 20/26 patients (77%) remained clinically improved: 54% were in NYHA class I and 23% in class II. CONCLUSIONS: BMV is an effective short- and long-term procedure for patients with previous surgical commissurotomy, with a low additional risk of complications. Thus, BMV can be considered the treatment of choice in these patients.

Determination of Cd, Co, Cu, Mn, Ni, Pb, and Zn by Inductively Coupled Plasma Mass Spectroscopy or Flame Atomic Absorption Spectrometry after On-line Preconcentration and Solvent Extraction by Flow Injection System

The concentrations of Cd, Co, Cu, Mn, Ni, Pb, and Zn in natural and sea waters are too low to be directly determined with by flame atomic absorption spectrometry (FAAS) or graphite furnace atomic absorption spectrometry (GFAAS). Specific sample preparations are requested that make possible the determination of these analytes by preconcentration or extraction. These techniques are affected by severe problems of sample contamination. In this work Cd, Co, Cu, Mn, Ni, Pb, and Zn were determined by inductively coupled plasma mass spectroscopy (ICP-MS) or by atomic absorption spectrometry, in fresh and seawater samples, after on-line preconcentration and following solvent elution with a flow injection system. Bonded silica with octadecyl functional group C18, packed in a microcolumn of 100-μl capacity, was used to collect diethyldithiocarbamate complexes of the heavy metals in aqueous solutions. The metals are complexed with a chelating agent, adsorbed on the C18 column, and eluted with methanol directly in the flow injection system. The methanolic stream can be addressed to FAAS for direct determination of Cu, Ni, and Zn, or collected in a vial for successive analysis by GFAAS. The eluted samples can be also dried in a vacuum container and restored to a little volume with concentrated HNO3 and Milli-Q water for analysis by ICP-MS or GFAAS.

[Percutaneous mitral valvuloplasty: the immediate and long-term results]. / Valvuloplastica mitralica percutanea: risultati immediati e a lungo termine.

BACKGROUND: Between December 1988 and December 1992, 235 patients (pts) underwent percutaneous balloon mitral valvuloplasty (PBMV). METHODS AND RESULTS: There were 55 men (23%) aged 49 +/- 13 years and 180 women (77%) aged 51 +/- 13 years. Previous surgical commissurotomy (PSC) had been performed in 22 pts. Procedure was successful (area > 1.5 cm2 or area increase > or = 50% without mitral regurgitation > 2+) in 91.9% of pts, with increase in mitral valve area from 1.05 +/- 0.2 to 2.26 +/- 0.6 cm2, decrease of transvalvular mean pressure gradient from 14.4 +/- 5.5 to 6.05 +/- 4.91 mm Hg and increase of cardiac index from 2.79 +/- 0.75 to 3.17 +/- 0.9 l/m'/m2 (p < 0.001). Insufficient increase in valve area occurred in 3.8% of pts. Major complications included 5 pts with 3+ mitral regulation (MR) requiring mitral valve replacement (MVR), 2 TIA's (0.85%) and 1 pericardiocentesis (0.42%). At follow-up (mean 18.9 months) clinical improvement was achieved in 93.8% of pts (NYHA class from 2.4 to 1.3); mitral valve area was 1.9 +/- 0.4 cm2 and mean mitral valve gradient 5.3 +/- 2.3 mm Hg. Restenosis (area < 1.5 cm2 or > or = 50% loss of initial gain) occurred in 24 pts (10.16%). Six pts required MVR; 1 pt underwent a second successful PBMV. Multivariate study (logistic regression) identified as independent factors of severe MR NYHA class and PSC; echo score, age and basal mean mitral valve gradient were independent factors for restenosis. CONCLUSIONS: In conclusion, PBMV is a safe technique and stable clinical improvement can be obtained in the majority of pts.