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31.

Objectives

In systemic sclerosis (SSc), left ventricular diastolic dysfunction reflects primary myocardial involvement of the disease. We aimed to assess the abnormalities of the diastolic function, analyze the characteristics of the disease progression, and investigate the prognostic value of diastolic dysfunction in SSc patients.

Patients and methods

A total of 34 SSc patients (57 ± 12 years, 31 female) were involved in the study. The following traditional or tissue Doppler parameters of left ventricular diastolic function were obtained: E/A, lateral E?, E/E?, left ventricular mass index (LVM index), and maximal left atrial (LA) volume index. Measurements were repeated after 5.5 years.

Results

At baseline, diastolic dysfunction was found in 62% of the SSc patients. Follow-up time was 5.4 ± 1.2 years. A total of 6 patients died of heart failure. In univariate Cox regression analysis, age (HR = 1.08, p < 0.05), LVM index (HR = 1.07, p < 0.01), lateral E? (HR = 1.57, p = 0.05), and LA volume index (HR = 1.11, p < 0.01) were predictors of survival. During the follow-up, significant increase in LA volume index (27.5 ± 9.7 vs. 35.4 ± 10.6 cm3/m2, p < 0.001) and E/E? was found (7.6 ± 2.5 vs. 8.7 ± 3.8, p < 0.05) while E? did not change (9.6 ± 2.6 vs. 9.2 ± 1.9 cm/s, NS). The increase in LA volume index showed positive correlation (r = 0.46, p < 0.05) while the decrease in E? values showed negative correlation (r = −0.54, p < 0.01) with the duration of the SSc.

Conclusion

In SSc patients, left ventricular diastolic dysfunction is highly prevalent and is associated with increased risk of mortality. Our data suggest that in the advanced phase of the disease, the myocardial fibrotic processes burns out while the increase of the filling pressure progresses continuously.  相似文献   
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Background

Operations on the infrarenal aorta can cause ischemic-reperfusion (IR) injury in local tissues, which could result in remote organ (e.g., lung) damage. Treatment of such injuries remains an unresolved problem.

Objectives

Our aim was to reduce remote lung damage after lower limb IR by means of postconditioning.

Materials and methods

Male Wistar rats were divided into three groups: Sham-operated, IR, and Postconditioned (PostC). In the latter two groups rats underwent 180 min of exclusion of the infrarenal aorta. The reperfusion time was 4 h. Serum-free radical levels, tumor necrosis factor-α and interleukin-6 concentrations, histologic changes in the lung, wet/dry-ratio, myeloperoxidase activity, heat shock protein 72 level and blood gas changes were investigated.

Results

Postconditioning reduced histological damage in the lung (P < 0.05). Free radical levels and tumor necrosis factor-α concentrations were significantly lower in the PostC group than in the IR group (P < 0.05 and P < 0.01, respectively). Interleukin-6 concentrations did not significantly differ in the PostC group. Compared with the IR group, lung myeloperoxidase activity was lower in the PostC group. Decreased pulmonary heat shock protein 72 level was observed in the PostC group compared with the IR group and the wet/dry-ratio was also significantly lower in the PostC group (P < 0.05). A noticeably higher arterial pO2 level was manifest in the PostC group after 2 and 4 h of reperfusion (P < 0.05).

Conclusions

Postconditioning reduced lung damage under experimental conditions, in the early period of reperfusion after lower limb IR injury.  相似文献   
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