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31.
Exercise testing induces fatal thromboembolism from mechanical mitral valve   总被引:1,自引:0,他引:1  
Thromboembolism is still one of the most important complications of prosthetic heart valves. Embolism to a major coronary branch is rare, but acute proximal occlusions can be fatal, even when the coronary arteries are otherwise normal and intervention is rapid. We report a fatal complication of an exercise test in a patient who had a St. Jude bileaflet mitral valve. After an exercise test, a 42-year-old woman with a mechanical prosthetic valve had a severe hemodynamic collapse with acute ST segment changes. Coronary angiography showed a totally occluded left main coronary artery with TIMI grade 0 to 1 flow. Rapid injection of contrast material and the passage of a floppy guidewire through the thrombus restored a TIMI grade 3 flow. Angiography showed no coronary atherosclerostic involvement. Despite successful coronary reperfusion, intra-aortic balloon counterpulsation, and intensive medication, the patient died. This case demonstrates that exercise testing should be applied with great caution in patients with prosthetic valves, and only after a careful evaluation of valve function. We recommend transesophageal echocardiography prior to exercise testing in these patients.  相似文献   
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In this multicenter, retrospective study, we evaluated the efficacy and safety of biologic therapies, including anti-TNFs, in secondary (AA) amyloidosis patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). In addition, the frequency of secondary amyloidosis in RA and AS patients in a single center was estimated. Fifty-one AS (39M, 12F, mean age: 46.7) and 30 RA patients (11M, 19F, mean age: 51.7) with AA amyloidosis from 16 different centers in Turkey were included. Clinical and demographical features of patients were obtained from medical charts. A composite response index (CRI) to biologic therapy—based on creatinine level, proteinuria and disease activity—was used to evaluate the efficacy of treatment. The mean annual incidence of AA amyloidosis in RA and AS patients was 0.23 and 0.42/1000 patients/year, respectively. The point prevalence in RA and AS groups was 4.59 and 7.58/1000, respectively. In RA group with AA amyloidosis, effective response was obtained in 52.2 % of patients according to CRI. RA patients with RF positivity and more initial disease activity tended to have higher response rates to therapy (p values, 0.069 and 0.056). After biologic therapy (median 17 months), two RA patients died and two developed tuberculosis. In AS group, 45.7 % of patients fulfilled the criteria of good response according to CRI. AS patients with higher CRP levels at the time of AA diagnosis and at the beginning of anti-TNF therapy had higher response rates (p values, 0.011 and 0.017). During follow-up after anti-TNF therapy (median 38 months), one patient died and tuberculosis developed in two patients. Biologic therapy seems to be effective in at least half of RA and AS patients with AA amyloidosis. Tuberculosis was the most important safety concern.  相似文献   
34.
Angiographic prevalence of myocardial bridging.   总被引:2,自引:0,他引:2  
OBJECTIVE: Muscle fibers overlying the intramyocardial segment of an epicardial coronary artery are termed myocardial bridging. Variable prevalence has been described at autopsy and angiographic series with small and large sample sizes. The aim of the study was to investigate the angiographic prevalence of myocardial bridging in 25982 patients from Turkey. METHODS: We performed a retrospective study, evaluated the cases with myocardial bridging among patients undergone selective coronary angiography, and searched the angiographic prevalence of myocardial bridging in a very large sample size. We studied also the correlation between the severity of the bridging and risk factors for coronary artery disease. RESULTS: Among 25982 patients we found 316 cases of myocardial bridging in a retrospective manner. The total prevalence was 1.22%. Although, 96.52% of patients with myocardial bridging had the lesion in the left anterior descending coronary artery (LAD) as expected, distribution of bridges between mid- and distal segments were almost equal (52.79% and 47.21%, respectively). We subclassified patients in two groups, Group A (<50% of systolic compression) and Group B (>or=50% of systolic compression), according to the amount of systolic compression of LAD and studied relationship of risk factors for coronary artery disease between groups. Another subclassification was also made for patients having myocardial bridging without coronary or valvular heart disease and hypertrophic obstructive cardiomyopathy; Group 1 (<50% of systolic compression) and Group 2 (>or=50% of systolic compression). In these patients we studied correlation between the severity of the myocardial bridging and risk factors for coronary artery disease. The prevalence of bridges in circumflex and right coronary arteries individually and in all arteries as combination was also studied. CONCLUSION: In a very large group of patients from Turkey undergone selective coronary artery angiography, the angiographic prevalence of myocardial bridging was slightly higher than expected. Only diabetes mellitus as a risk factor for coronary artery disease was higher in groups representing <50% of systolic compression (Group A and 1) than in groups representing >or=50% of systolic compression (Group B and 2) but the importance of this result is not known.  相似文献   
35.

Background and Aim:

Ischemia/reperfusion (I/R) injury in the liver occurs after a prolonged period of ischemia followed by restoration of hepatic blood perfusion. During the surgery of abdominal aorta, I/R injury causes damage to lower extremities and many organs, especially liver. The antioxidant and tumor necrosis factor-alpha (TNF-α) suppression effects of topiramate (TPM) have been reported in several studies. We evaluated the potential protective effect of TPM on cellular damage in liver tissue during I/R injury.

Materials and Methods:

Thirty male Wistar albino rats were divided into three groups: Control, I/R, and I/R plus TPM (I/R + TPM) groups. Laparotomy without I/R injury was performed in the control group. After laparotomy, cross-ligation of infrarenal abdominal aorta was applied for 2 h in I/R groups that was followed by 2 h of reperfusion. TPM (100 mg/kg/day) was orally administrated to the animals in the I/R + TPM group for seven consecutive days before I/R procedure.

Results:

The I/R group''s TNF-α and interleukin-6 (IL-6) levels were significantly higher than those of the control (P = 0.010; P = 0.002) and I/R + TPM groups (P = 0.010; P = 0.002, respectively). Asymmetric dimethyl arginine (ADMA) levels of I/R group were higher than the control (P = 0.015) and I/R + TPM groups. I/R caused serious histopathological damage to liver tissue; however, TPM led to very low histopathological changes.

Conclusion:

Our data demonstrated that TPM treatment prominently decreases the severity of liver I/R injury. TPM pretreatment may have preventive effects on liver injury via I/R during intra-abdominal surgery.  相似文献   
36.
Cardiovascular complications are the most common causes of morbidity and mortality in acromegaly. However, there is little data regarding cardiac autonomic functions in these patients. Herein, we aimed to investigate several parameters of cardiac autonomic functions in patients with acromegaly compared to healthy subjects. We enrolled 20 newly diagnosed acromegalic patients (55 % female, age:45.7 ± 12.6 years) and 32 age- and gender-matched healthy subjects. All participants underwent 24 h Holter recording. Heart rate recovery (HRR) indices were calculated by subtracting 1st, 2nd and 3rd minute heart rates from maximal heart rate. All patients underwent heart rate variability (HRV) and QT dynamicity analysis. Baseline characteristics were similar except diabetes mellitus and hypertension among groups. Mean HRR1 (29.2 ± 12.3 vs 42.6 ± 6.5, p = 0.001), HRR2 (43.5 ± 15.6 vs 61.1 ± 10.8, p = 0.001) and HRR3 (46.4 ± 16.2 vs 65.8 ± 9.8, p = 0.001) values were significantly higher in control group. HRV parameters as, SDNN [standard deviation of all NN intervals] (p = 0.001), SDANN [SD of the 5 min mean RR intervals] (p = 0.001), RMSSD [root square of successive differences in RR interval] (p = 0.001), PNN50 [proportion of differences in successive NN intervals >50 ms] (p = 0.001) and high-frequency [HF] (p = 0.001) were significantly decreased in patients with acromegaly; but low frequency [LF] (p = 0.046) and LF/HF (p = 0.001) were significantly higher in acromegaly patients. QTec (p = 0.009), QTac/RR slope (p = 0.017) and QTec/RR slope (p = 0.01) were significantly higher in patients with acromegaly. Additionally, there were significant negative correlation of disease duration with HRR2, HRR3, SDNN, PNN50, RMSSD, variability index. Our study results suggest that cardiac autonomic functions are impaired in patients with acromegaly. Further large scale studies are needed to exhibit the prognostic significance of impaired autonomic functions in patients with acromegaly.  相似文献   
37.

Background

The aim of the study was to investigate the relationship of dysfunctional attitudes, self-esteem, personality, and depression with Internet addiction in university students.

Methods

A total of 720 university students participated in the study in Bülent Ecevit University English Preparatory School which offers intensive English courses. Students were evaluated with a sociodemographic data form, Beck Depression Inventory (BDI), Dysfunctional Attitudes Scale form A (DAS-A), Internet Addiction Scale (IAS), Rosenberg Self-Esteem Scale (RSES), and Eysenck Personality Questionnaire Revised/Abbreviated Form (EPQR-A).

Results

The results indicated that 52 (7.2%) of the students had Internet addiction. There were 37 (71.2%) men, 15 (28.8%) women in the addicted group. While the addicted groups' BDI, DAS-A perfectionistic attitude, need for approval, RSES, EPQR-A neuroticism, and psychoticism scores were significantly higher, EPQR-A lie scores were significantly lower than those of the non addicted group. According to the multiple binary logistic regression analysis, being male, duration of Internet usage, depression, and perfectionistic attitude have been found as predictors for Internet addiction. It has been found that perfectionistic attitude is a predictor for Internet addiction even when depression, sex, duration of Internet were controlled.

Conclusions

To the knowledge of the researchers, this study is the first study to show the dysfunctional attitudes in Internet addiction. It can be important to evaluate dysfunctional attitudes, personality, self-esteem and depression in people with Internet addiction. These variables should be targeted for effective treatment of people with Internet addiction in cognitive behavioral therapy.  相似文献   
38.
ObjectiveIn this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis.MethodsSixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial–carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12th month.ResultsMean age of the patients was 49 ± 11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57 ± 47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0 ± 0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium–phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02 ± 2.51 m/s to 9.61 ± 2.39 m/s and from 28.8 ± 10.3% to 26.2 ± 12.1%; p = 0.008 and p = 0.04, respectively). While augmentation index increased in the CHD group (28.0 ± 9.4 to 31.0 ± 10.7%, p = 0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135 ± 28 to 143 ± 25%, p = 0.01 and from 294 ± 34 ms to 281 ± 34 ms, p = 0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio.ConclusionsThese data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.  相似文献   
39.
40.
The main purpose of this study was to investigate the relation between carotid intima-media thickness (CIMT) and coronary artery disease (CAD) complexity. Consecutive patients (n = 360) with CAD confirmed by coronary angiography were enrolled. Mean CIMT and the overall SYNTAX score (SXscore) were 0.87 ± 0.12 mm and 15 ± 9, respectively. In univariate analysis, there was a significant correlation between the overall SXscore and CIMT (r = .42, P < .001), age (r = .23, P < .001), hypertension (r = .27, P = 0.001), diabetes (r = 0.11, P = 0.02), smoking (r = .24, P = .01), dyslipidemia (r = .2, P = 0.03), and β-blocker use (r = .19, P < .001). In multivariate analysis, CIMT (β = .34, P < .001) and age (β = .11, P < .019) were independently associated with SXscore. We have demonstrated a significant relation between CIMT and SXscore. Although this study is correlative and no causative conclusions can be drawn, our findings suggest that increased CIMT could reflect complex coronary artery lesions.  相似文献   
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