The role of embolic protection devices during carotid stenting prior to cardiac surgery in asymptomatic patients: empty filters?

OBJECTIVES: The purpose of this study was to analyze the debris captured in the distal protection filters used during carotid artery stenting (CAS). BACKGROUND: CAS is an option available to high-risk patients requiring revascularization. Filters are suggested for optimal stroke prevention during CAS. METHODS: From May 2005 to June 2007, filters from 59 asymptomatic patients who underwent CAS were collected and sent to a specialized laboratory for light-microscope and histological analysis. Peri- and postprocedural outcomes were assessed during 1-year follow-up. RESULTS: On the basis of biomedical imaging of the filter debris, the captured material could not be identified as embolized particles from the carotid plaque. On histological analysis the debris consisted mainly of red blood cell aggregates and/ or platelets, occasionally accompanied by granulocytes. We found no consistent histological evidence of embolized particles originating from atherosclerotic plaques. Post-procedure, three neurological events were reported: two (3.4%) transient ischemic attacks (TIA) and one (1.7%) ipsilateral minor stroke. CONCLUSION: The filters used during CAS in asymptomatic patients planned for cardiac surgery often remained empty. These findings may be explained by assuming that asymptomatic patients feature a different atherosclerotic plaque composition or stabilization through antiplatelet medication. Larger, randomized trials are clearly warranted, especially in the asymptomatic population.

Mutations in EDARADD account for a small proportion of hypohidrotic ectodermal dysplasia cases.

BACKGROUND: Hypohidrotic ectodermal dysplasia (HED) is characterized by abnormal development of the eccrine sweat glands, hair and teeth. The X-linked form of the disease, caused by mutations in the EDA gene, represents the majority of HED cases. Autosomal dominant and recessive forms occasionally occur and result from mutations in at least two other genes: EDAR and EDARADD. EDARADD interacts with the TAB2/TRAF6/TAK1 complex, which is necessary for NF-kappaB activation by EDAR. OBJECTIVES: To determine frequency of EDARADD, TRAF6, TAB2 and TAK1 mutations in HED. MATERIALS AND METHODS: We have screened 28 familial or sporadic HED cases with no mutations in the EDA and EDAR genes for EDARADD, TRAF6, TAB2 and TAK1 mutations. RESULTS: We identified one EDARADD 6-bp homozygous in-frame deletion (c.402-407del, p.Thr135-Val136del) in a patient born to consanguineous parents. Functional studies showed that the p.Thr135-Val136del impaired the EDAR-EDARADD interaction and then severely inhibited NF-kappaB activity. In the remaining 27 patients, we failed to find causative mutations in EDARADD, or in TRAF6, TAB2 or TAK1. CONCLUSIONS: Our study demonstrates that EDARADD mutations are not a frequent cause of HED, while mutations in TRAF6, TAB2 and TAK1 may not be implicated in this disease.

Cases of influenza A(H1N1)v reported in Turkey, May-July 2009.

Following the declaration by the World Health Organization (WHO) of human cases of infection with a new influenza A(H1N1)v virus of swine origin, the Turkish Ministry of Health launched a case-based reporting of influenza A(H1N1)v throughout the country on 27 April 2009. The index case was detected on 15 May 2009. As of 17 July 2009 the number of laboratory-confirmed cases of influenza A(H1N1)v totaled 128 of whom 38 were indigenous cases.

Autosomal dominant anhidrotic ectodermal dysplasias at the EDARADD locus.

Anhidrotic ectodermal dysplasia (EDA) is a disorder of ectodermal differentiation characterized by sparse hair, abnormal or missing teeth, and inability to sweat. X-linked EDA is the most common form, caused by mutations in the EDA gene, which encodes ectodysplasin, a member of the tumor necrosis factor (TNF) family. Autosomal dominant and recessive forms of EDA have been also described and are accounted for by two genes. Mutations in EDAR, encoding a TNF receptor (EDAR) cause both dominant and recessive forms. In addition, mutations in a recently identified gene, EDARADD, encoding EDAR-associated death domain (EDARADD) have been shown to cause autosomal recessive EDA. Here, we report a large Moroccan family with an autosomal dominant EDA. We mapped the disease gene to chromosome 1q42.2-q43, and identified a novel missense mutation in the EDARADD gene (c.335T>G, p.Leu112Arg). Thus, the EDARADD gene accounts for both recessive and dominant EDA. EDAR is activated by its ligand, ectodysplasin, and uses EDARADD to build an intracellular complex and activate nuclear factor kappa B (NF-kB). We compared the functional consequences of the dominant (p.Leu112Arg) and recessive mutation (p.Glu142Lys), which both occurred in the death domain (DD) of EDARADD. We demonstrated that the p.Leu112Arg mutation completely abrogated NF-kB activation, whereas the p.Glu142Lys retained the ability to significantly activate the NF-kB pathway. The p.Leu112Arg mutation is probably a dominant negative form as its cotransfection impaired the wild-type EDARADD's ability to activate NF-kB. Our results confirm that NF-kB activation is impaired in EDA and support the role of EDARADD DD as a downstream effector of EDAR signaling.

Cardiac surgery and operative mortality in 1992 and 2002: the St Antonius experience.

OBJECTIVE: Comparing the changes in open-heart surgical procedures and hospital mortality in 1992 with 2002. DESIGN AND SETTING: Retrospective investigation at St Antonius Hospital in Nieuwegein. METHOD: A comparison of the open-heart surgical procedures, hospital mortality and age distribution of the operated patients was made, using the database of the Department of Cardiothoracic Surgery. RESULTS: The total number of open-heart surgical procedures increased. There were more combined procedures, aortic valve replacements and reconstructions of the thoracic aorta. The total number of reoperations decreased. In 2002 the use of an arterial conduit for coronary bypass procedures reached 94%, and the radial artery was used for the first time. The mean patient age and the hospital mortality were higher in 2002. CONCLUSION: Comparing cardiovascular surgery in 1992 to 2002 showed an increase in complicated procedures and older age groups of patients. This may be the reason for higher overall mortality. The mean patient age increased considerably from 1992 to 2002, together with the number of combined procedures and aortic valve replacements with biological valve prostheses. These trends give cardiovascular surgery a challenging future, to treat the patient adequately and keeping the mortality and complication rates low.

Effect of coumarins started before coronary angioplasty on acute complications and long-term follow-up: a randomized trial.

BACKGROUND: Coronary angioplasty frequently creates a thrombogenic surface, with subsequent mural thrombosis that may lead to acute complications and possibly stimulates the development of restenosis. Whether coumarins can prevent these complications is unclear. The objective of this open, randomized trial was to assess the clinical effect of coumarins started before coronary angioplasty and continued for 6 months. METHODS AND RESULTS: Before coronary angioplasty, 530 patients were randomly assigned to aspirin plus coumarins and 528 patients to aspirin alone. At the start of the angioplasty, the mean international normalized ratio was 2.7+/-1.1; during follow-up, it was 3.0+/-1.1. At 30 days, the composite end point of death, myocardial infarction, target-lesion revascularization, and stroke was observed in 18 patients (3.4%) treated with aspirin plus coumarin compared with 34 patients (6.4%) treated with aspirin alone (relative risk, 0.53; 95% CI, 0.30 to 0.92). At 1 year, these figures were 14.3% and 20.3%, respectively (relative risk, 0.71; 95% CI, 0.54 to 0.93). The incidence of major bleeding and false aneurysm during hospitalization was 3.2% and 1.0%, respectively (relative risk, 3.39; 95% CI, 1.26 to 9.11). The benefit of coumarins was observed in both stented and nonstented patients. CONCLUSIONS: Coumarins in addition to aspirin started before PTCA and continued for 6 months was more effective than aspirin alone in the prevention of acute and late complications after coronary angioplasty. This benefit was accompanied by a small but significant increase in bleeding complications.

Ten-year follow-up of percutaneous transluminal coronary angioplasty for proximal left anterior descending coronary artery stenosis in 351 patients.

OBJECTIVES: We sought to evaluate the short- and long-term results of balloon angioplasty for stenoses in the proximal left anterior descending coronary artery. BACKGROUND: Both the supposedly high rate of acute complications and relatively poor long-term results of balloon angioplasty for stenoses in the proximal left anterior descending coronary artery have led to a search for alternative interventional techniques. METHODS: We analyzed the success rates and long-term follow-up results in 351 consecutive patients who underwent balloon angioplasty for stenosis of the left anterior descending coronary artery proximal to its first side branch. The power of the study was >80% in detecting a difference of 9% in the proportion of patients who survived at 10 years, assuming an 80% survival rate in the control group. RESULTS: There were 60 ostial and 291 nonostial stenoses. Follow-up lasted a median of 85 months (range 0 to 137) and was 100% complete. The angiographic success rate was 90.9%. The clinical success rate was 86.3%. Nine patients (2.6%) died, 17 (4.8%) needed emergency coronary artery bypass graft surgery, and 10 (2.8%) developed a myocardial infarction. Several patients had subsequent complications. The success and complication rates were not significantly different for patients with ostial and nonostial stenoses. Ten years after balloon angioplasty, freedom from mortality was 80%, freedom from cardiac death was 87%, freedom from myocardial infarction was 84%, freedom from vessel-related reinterventions was 66%, and freedom from angina pectoris was 33%. There were more reinterventions for ostial stenoses, with a 1-year relative risk of ostial versus nonostial stenoses for related reinterventions of 1.7 (95% confidence interval 1 to 2.8, p = 0.049). CONCLUSIONS: More than 10 years ago, balloon angioplasty for stenoses in the proximal left anterior descending coronary artery, either ostial or nonostial, had a high success rate. Although the long-term results are satisfactory, ostial stenoses are associated with a higher early clinical restenosis rate requiring more reinterventions.

Pravastatin reduces restenosis two years after percutaneous transluminal coronary angioplasty (REGRESS trial).

The Regression Growth Evaluation Statin Study (REGRESS) is a placebo-controlled multicenter study designed to assess the effect of 2-year treatment with pravastatin on the progression and regression of angiographically documented coronary artery disease. One of the secondary end points was the occurrence of 2-year restenosis in the percutaneous transluminal coronary angioplasty (PTCA) block. We randomly assigned eligible patients to receive pravastatin 40 mg once daily or placebo. The end point was the percent diameter stenosis of the target lesion at 24 months, as assessed by (semi)quantitative coronary angiography. Two hundred twenty-one patients underwent scheduled PTCA, which was considered successful in 201 patients. One hundred seventy-eight patients underwent angiographic restudy (89%). The patients in the pravastatin group (n = 109) and placebo group (n = 112) were similar at baseline. Percent diameter stenosis before angioplasty was 78 +/- 14% (mean +/- SD) in the pravastatin group and 80 +/- 14% in the placebo group (p = 0.46). At follow-up, the percent diameter stenosis was 32 +/- 23% in the pravastatin group and 45 +/- 29% in the placebo group (p < 0.001). Clinical restenosis was significantly lower in the pravastatin group (7%) compared with the placebo group (29%) (p < 0.001). Risk reduction for all events was 58%. We conclude that treatment with pravastatin reduces 2-year clinical and angiographic restenosis.

Percutaneous transluminal angioplasty of the left subclavian artery to prevent or treat the coronary-subclavian steal syndrome.

A hemodynamic significant left subclavian artery stenosis or occlusion proximal to the origin of the left internal mammary artery (LIMA) can result in an impaired or reversed flow through the LIMA and the coronary artery to which it has been anastomosed. In this study, we report on our immediate and long-term follow-up results in 31 consecutive patients who underwent percutaneous transluminal coronary angioplasty of the left subclavian artery shortly before or after coronary artery bypass grafting with use of the LIMA.

Long-term results after successful percutaneous transluminal coronary angioplasty in patients over 75 years of age.

A prospective study comparing the long-term results of balloon angioplasty in patients over 75 years of age with those in a younger patient group is not available. A total of 192 consecutive patients aged > or = 75 years (group I) who underwent a balloon angioplasty were matched with 192 control patients aged 40 to 65 years (group II). The groups were matched for gender, angina pectoris class, left ventricular function, 1-, 2-, and 3-vessel coronary artery disease, and previous myocardial infarction. The mean follow-up was 40.4 months (range 0 to 110). Actuarial analysis (freedom from events) after 5 years yielded the following results for group I versus group II: free from death remained 77.1% versus 97.9% (p = 0.0001), from cardiac death 92.4% versus 97.9% (p = 0.049), and from angina pectoris 54.6% versus 75.1% (p = 0.03). The differences were not significant for those remaining free from myocardial infarction, repeat balloon angioplasty, or coronary artery bypass grafting. When elderly patients with complete revascularization (n = 127) were compared with a matched control group of 127 patients aged 40 to 65 years who underwent complete revascularization, there was only a significant difference in noncardiac death rates. We conclude that patients > 75 years of age have a significant higher cardiac and noncardiac death rate and a higher incidence of angina pectoris after successful balloon angioplasty. However, the incidence of reintervention and myocardial infarction is lower in the elderly. If complete revascularization is achieved in the elderly, then freedom from cardiac death and recurrence of angina pectoris would be comparable to that in younger patients.

Percutaneous transluminal coronary angioplasty in patients with prior coronary artery bypass grafting. Long-term results.

In 83 patients with previous coronary artery bypass grafting, 92 percutaneous transluminal coronary angioplasty attempts were done, 33 in a venous bypass graft (success rate 97%) and 59 in a native coronary artery (success rate 86.4%). There were no procedural-related deaths and two myocardial infarctions. Forty-six percent of the patients with successful angioplasty after previous bypass grafting remain symptom free after 5 years versus 79% of the patients without previous bypass grafting (p less than 0.001). Long-term success rates for native vessel angioplasty as compared with bypass graft angioplasty are similar. Patients with a short interval between the recurrence of angina after bypass grafting and the angioplasty attempt have a better chance of long-term success. Repeat angiography indicates that a restenosis occurs after angioplasty of a venous graft in 31% and in the native system in 28.6% and that signs of progression of coronary artery disease elsewhere are present in 30%. Of the 83 patients, 11 had reoperation eventually. We conclude that percutaneous transluminal coronary angioplasty after coronary bypass grafting gives less satisfactory results than a primary procedure, that angioplasty provides symptomatic relief in a smaller number of patients than in those with primary angioplasty, but that symptomatic relief is often sufficient to further postpone or prevent bypass grafting and can be achieved with low mortality and low complication rates.

Stenting of "unprotected" left main coronary artery stenoses: early and late results.

OBJECTIVE: To assess short and long term efficacy of coronary stent implantation for unprotected left main coronary artery stenosis. DESIGN: Retrospective follow up study. SETTING: Tertiary referral centre for interventional cardiology and cardiac surgery. PATIENTS: Eighteen consecutive patients (12 men; age 70.8 years) between May 1993 and July 1996. Ten patients presented with stable angina and underwent the procedure electively, eight patients presented either with unstable angina or myocardial infarction and underwent the procedure in emergency. INTERVENTION: Johnson and Johnson Palmaz-Schatz stents were used in 16 patients, and a Microstent and a Gianturco-Roubin in one patient each. An intra-aortic balloon pump was prophylactively used for two patients in the elective group. In the acute group, six required an intra-aortic balloon pump. MAIN OUTCOME MEASURES: Procedural success rate and major adverse cardiac events. RESULTS: Successful stent implantation was achieved in all patients. In the elective group, no major adverse cardiac event occurred during the procedure, but one patient had to undergo repeated angioplasty before discharge. All patients of the elective group were discharged alive and there has been one non-cardiac death during a follow up of (mean (SD)) 10 (4) months. In the emergency group, one patient died during the procedure, one patient developed a non Q-wave myocardial infarction, one patient underwent emergency coronary bypass surgery, while another patient died suddenly before hospital discharge. Six patients of the emergency group were discharged alive and there has been one non-cardiac death during a follow up of 7 (4) months. CONCLUSIONS: Elective stent implantation for unprotected left main coronary artery stenosis is safe and effective in selected stable patients. Urgent stent implantation, however, cannot be considered as a definitive procedure in emergency situation.

The influence of angiographic endpoints on the outcome of lipid intervention studies. A proposal for standardization. REGRESS study group.

The aims of this study were to evaluate the influence of different coronary angiographic endpoints on the outcome of lipid intervention studies and to formulate a proposal for angiographic endpoint standardization. In recent angiographic intervention studies a confusing diversity in angiographic endpoints has been used to determine the outcome. In addition, differences in study populations (eg, bypass patients included or not) could influence results. This makes comparisons between studies cumbersome and raises the question to what extent the results of various studies may be subject to the selection of angiographic endpoints. The investigators compared three frequently used endpoints (mean segment diameter, minimum obstruction diameter, and % stenosis) in a group of 505 patients who had just finished a trial designed to assess the effect of cholesterol lowering by pravastatin. To exclude a potential bias this analysis was carried out at the time that the study was still blinded. They found poor intercorrelation coefficients for mean segment diameter calculated in different ways, ranging from 0.55 to 0.95, dependent on inclusion or exclusion of segments influenced by coronary angioplasty or bypass grafting and on whether or not a value of 0 was assumed for occluded segments and segments distal to occlusions. The correlation between mean segment diameter and minimum obstruction diameter was 0.79; between minimum obstruction diamete and % stenosis, 0.85; and between mean segment diameter and % stenosis, only 0.64. Different endpoints sometimes correlate poorly. This may lead to differences in results of angiographic intervention trials. The authors propose standardization by (1) using both mean sement diameter and minimum obstruction diameter as endpoints and (2) excluding from the primary analysis segments influenced by mechanical interventions.

Influence of human leukocyte interferon on IgG on the replication of herpes simplex virus in nervous tissue in vitro.

Herpes simplex virus type 1 (HSV-1) replicated productively in rabbit and guinea pig ganglia and nerve organ cultures when inoculated in high titres. Treatment with IgG 20 hr before and 48 hr after infection produced a delay of 4 to 7 days in the recovery of HSV-1 by the method of co-cultivation. The same result was obtained when IgG was combined with human leukocyte interferon. There was no difference in the period up to HSV recovery between the groups treated with interferon alone and the HSV control. Morphological evidence by light and electron microscopy of viral productive infection was obtained in all the cell types of nervous tissues infected in vitro.

A comparative histological study of non-porous and micro-porous (algae-derived) hydroxylapatite ceramics.

Two different types of hydroxylapatite ceramics were examined histologically to assess their effects on the healing of standardized bone defects drilled in the mandibular bone of beagles. After 40 days both materials were totally enclosed by newly-formed bone, but only the defects filled with micro-porous hydroxylapatite were found to show bone incorporation which is a good indicator of implant stability. These results suggest that the physio-chemical similarities between the micro-porous hydroxylapatite and native bone may promote effective bone incorporation which can increase the stability of implants.

Early and late effects of coumarin therapy started before percutaneous coronary intervention: Clinical, angiographic and cost-effective outcome of the Balloon Angioplasty and Anticoagulation Study (BAAS).

BACKGROUND: Coronary angioplasty frequently creates a thrombogenic surface with subsequent mural thrombosis that may lead to acute complications and possibly stimulates the development of restenosis. Whether coumarins can prevent these complications is unclear. METHODS: In the Balloon Angioplasty and Anticoagulation Study (BAAS), the effect of coumarins started before the procedure on early and late outcome was studied. Patients were randomised to aspirin only or to aspirin plus coumarins. Half of the patients were randomised to undergo six-month angiographic follow-up. Study medication was started one week before coronary angioplasty and the target international normalised ratio (INR) was 2.1-4.8 during angioplasty and six-month follow-up. 'Optimal' anticoagulation was defined as an INR in the target range for at least 70% of the follow-up time. In addition, cost-effectiveness of coumarin treatment was measured. RESULTS: At one year death, myocardial infarction, target-lesion revascularisation and stroke were observed in 14.3% of the 530 patients randomised to aspirin plus coumarin versus in 20.3% of the 528 patients randomised to aspirin alone (relative risk 0.71; 95% CI 0.54-0.93). The incidence of major bleedings and false aneurysms during hospitalisation was 3.2% and 1.0%, respectively, (relative risk 3.39; 95% CI 1.26-9.11). Optimal anticoagulation was an independent predictor of late thrombotic events (relative risk, 0.33; 95% CI, 0.19-0.57). Quantitative coronary analysis was performed of 301 lesions in the ASA group and of 297 lesions in the coumarin group. At six months, the minimal luminal diameter was similar in the ASA and coumarin group. However, optimal anticoagulation was an independent predictor of angiographic outcome at six months. Optimal anticoagulation led to a 0.21 mm (95% CI: 0.05-0.37) larger MLD as compared with suboptimal anticoagulation whereas aspirin use led to a 0.12 mm (95% CI -0.28-0.04) smaller MLD. When including all costs, the savings associated with coumarin treatment were estimated at € 235 per patient after one year. CONCLUSIONS: Coumarin pretreatment reduces early and late events in patients undergoing percutaneous coronary intervention at the expense of a small increase in nonfatal bleeding complications. Furthermore, an optimal level of anticoagulation is associated with a significantly better outcome as compared with a suboptimal level of anticoagulation. In addition, coumarin treatment reduces costs.

Long-term follow-up of coronary angioplasty in patients with diabetes compared with nondiabetics.

BACKGROUND: Some reports have indicated that in patients with diabetes mellitus and multivessel disease, coronary artery bypass surgery is preferred over percutaneous coronary intervention (PCI). We retrospectively compared outcome PCI in diabetic and nondiabetic patients. METHODS: Ninety-seven diabetics and 971 nondiabetics were included and randomised before PCI to aspirin alone or aspirin plus coumadin. Fifty diabetics and 481 nondiabetics underwent follow-up angiography. The primary endpoint comprised all-cause mortality, myocardial infarction or targetvessel revascularisation. RESULTS: Baseline characteristics were similar between the groups except for significantly more males and smokers among the nondiabetics. The diabetics had significantly more previous strokes, more left anterior descending coronary artery disease as well as more restenotic lesions and multivessel disease. At 30 days, the primary endpoint had occurred in five diabetics (5.2%) and 47 nondiabetics (4.9%), (p=0.8) and at one year in 17 (17.5%) and in 165 (17.1%), respectively (p=0.9). Event-free survival remained comparable during long-term follow-up (four years). Multivariate analysis showed no differences for the occurrence of any event (p=0.9, 95% CI 0.6-1.7). At six months, the minimal luminal diameter was significantly smaller in the diabetics (1.55±0.76 mm vs. 1.78±0.66 mm, p=0.01). Diabetics also had more restenosis (41% vs. 23%, p=0.003). CONCLUSION: Despite angiographical differences at six months between the diabetics and nondiabetics, both short-term and long-term clinical follow-up appeared to be similar.

Short segment pedicle screw instrumentation with an index level screw and cantilevered hyperlordotic reduction in the treatment of type-A fractures of the thoracolumbar spine.

The purpose of this study was to evaluate and compare the effect of short segment pedicle screw instrumentation and an intermediate screw (SSPI+IS) on the radiological outcome of type A thoracolumbar fractures, as judged by the load-sharing classification, percentage canal area reduction and remodelling. We retrospectively evaluated 39 patients who had undergone hyperlordotic SSPI+IS for an AO-Magerl Type-A thoracolumbar fracture. Their mean age was 35.1 (16 to 60) and the mean follow-up was 22.9 months (12 to 36). There were 26 men and 13 women in the study group. In total, 18 patients had a load-sharing classification score of seven and 21 a score of six. All radiographs and CT scans were evaluated for sagittal index, anterior body height compression (%ABC), spinal canal area and encroachment. There were no significant differences between the low and high score groups with respect to age, duration of follow-up, pre-operative sagittal index or pre-operative anterior body height compression (p = 0.217, 0.104, 0.104, and 0.109 respectively). The mean pre-operative sagittal index was 19.6° (12° to 28°) which was corrected to -1.8° (-5° to 3°) post-operatively and 2.4° (0° to 8°) at final follow-up (p = 0.835 for sagittal deformity). No patient needed revision for loss of correction or failure of instrumentation. Hyperlordotic reduction and short segment pedicle screw instrumentation and an intermediate screw is a safe and effective method of treating burst fractures of the thoracolumbar spine. It gives excellent radiological results with a very low rate of failure regardless of whether the fractures have a high or low load-sharing classification score.

The effects of gender difference on monocrotaline-induced pulmonary hypertension in rats.

The present study aimed to compare the effect of gender difference on hemodynamic consequences in the development of monocrotaline (MCT)-induced pulmonary hypertension in rat. The effect of antioxidant enzyme systems on the development of pulmonary hypertension mediated by the phytotoxin MCT and the effect of gender on these antioxidant systems were also investigated. For this purpose, the right ventricular pressures (RVPs) and right ventricular/heart weight (HW) ratios were compared between groups and the glutathione (GSH) level and superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) activities were determined in lung and liver tissue samples of rats. RVP and right ventricular/HW ratios significantly increased in the MCT group compared to the control group. In the MCT group, RVP was significantly higher in males than females. MCT-induced pulmonary hypertension resulted in decreased GSH level, decreased GST and SOD activities and increased CAT activity in lung and liver tissues of both male and female rats. In addition, the lung and liver GSH level and GST and SOD levels were higher in female control rats compared to male control rats. The results of the present study, that antioxidant enzyme activities were different between the groups, highlight the possible role of oxidative stress in the pathogenesis of MCT-induced pulmonary hypertension in rats. Moreover, the lower antioxidant defense capacity of male rats than female rats may be considered as a cause of more aggressive course of MCT-induced pulmonary hypertension in males compared to females.