Does arterio-venous fistula creation affects development of pulmonary hypertension in hemodialysis patients?

BACKGROUND: Pulmonary arterial hypertension (PAH) is a common complication in hemodialysis (HD) patients and its pathogenesis is not explained clearly. Arterio-venous fistulas (AVFs) creation may contribute to the development of PAH because of increased pulmonary artery blood flow. However, it was not prospectively evaluated that effect of AVF on the development of PAH. AIM: We aimed to evaluate the effects of AVF on PAH and the relationship between blood flow rate of AVF and pulmonary artery pressure (PAP) in HD patients. PATIENTS AND METHOD: The prospective study included 50 patients with end-stage renal disease. Before an AVF was surgically created for hemodialysis, the patients were evaluated by echocardiography. Then, an AVF was surgically created in the patients. After mean 76.14 ± 11.37 days, the second evaluation was performed by echocardiography. RESULTS: Before AVF creation, 17 (34%) out of 50 patients had PAH. The systolic PAP was significantly higher in the patients with PAH compared with patients without PAH (47.82 ± 9.82 mmHg vs. 30.15 ± 5.70 mmHg, respectively, p = 0.001). In the second evaluation, 19 (38%) out of 50 patients had PAH. The systolic PAP values were significantly higher in the patients with PAH compared with patients without PAH (47.63 ± 8.92 mmHg vs. 25.03 ± 7.69 mmHg, P = 0.001, respectively). There was no relationship between the blood flow rate of AVF and PAP. CONCLUSION: PAH is a common problem in HD patients. AVF has no significant effect on the development of PAH within a short period. Similarly, blood flow rate of AVF also did not affect remarkably the systolic PAP.

The long-term effects of arteriovenous fistula creation on the development of pulmonary hypertension in hemodialysis patients.

The aim of this prospective study was to evaluate long-term effects of arteriovenous fistula (AVF) on the development of pulmonary arterial hypertension (PAH) and the relationship between blood flow rate of AVF and pulmonary artery pressure (PAP) in the patients with end-stage renal disease (ESRD). This prospective study was performed in 20 patients with ESRD. Before an AVF was surgically created for hemodialysis, the patients were evaluated by echocardiography. Then, an AVF was surgically created in all patients. After mean 23.50 ± 2.25 months, the second evaluation was performed by echocardiography. Also, the blood flow rate of AVF was measured at the second echocardiographic evaluation. Pulmonary arterial hypertension was defined as a systolic PAP above 35 mmHg at rest. Mean age of 20 patients with ESRD was 55.05 ± 13.64 years; 11 of 20 patients were males. Pulmonary arterial hypertension was detected in 6 (30%) patients before AVF creation and in 4 (20%) patients after AVF creation. Systolic PAP value was meaningfully lower after AVF creation than before AVF creation (29.95 ± 10.26 mmHg vs. 35.35 ± 7.86 mmHg, respectively, P: 0.047). However, there was no significant difference between 2 time periods in terms of presence of PAH (P>0.05). Pulmonary artery pressure did not correlate with blood flow rate of AVF and duration after AVF creation (P>0.05). In hemodialysis patients, a surgically created AVF has no significant effect on the development of PAH within a long-term period. Similarly, blood flow rate of AVF also did not affect remarkably systolic PAP within the long-term period.

Effects of chronic obstructive pulmonary disease on coronary atherosclerosis.

The chronic systemic inflammation and oxidative stress are important features in chronic obstructive pulmonary disease (COPD). Atherosclerosis is accepted as an inflammatory disease. Both local and systemic inflammation and oxidative stress negatively affect the atherosclerotic process. Metabolic alterations, systemic inflammation, and neurohormonal activation frequently occur in patients with COPD. However, the impact of COPD on intensity and severity of atherosclerosis and morphology of stenotic lesions in patients with established coronary artery disease by coronary angiography is unknown. Eighty-eight patients who were diagnosed with COPD disease were enrolled in the study. Eighty-two patients without any pulmonary disease were included in the control group. Coronary angiography and blood gases analysis were performed in all patients. Gensini score and Extent score were used to evaluate the intensity and severity of atherosclerosis. Lesion morphologies were defined in all patients. The mean number of affected coronary arteries was 2.5 +/- 0.6 in the COPD group and 2.1 +/- 0.7 in the control group (P = 0.004). The mean Extent score was 37 +/- 16 in the COPD group and 23 +/- 11 in the control group (P = 0.001). The Gensini score in the COPD group was significantly higher than that in the control group (respectively 10.9 +/- 6.3 vs 6.6 +/- 4.1, P = 0.01). The number of critical lesions, and type B and C lesions were higher in the COPD group. Multivariate analysis demonstrated that COPD was independently predictive for Gensini score (odds ratio 1.371; 95% confidence interval 1.682-9.228; P = 0.002) and Extent score (odds ratio 1.648; 95% confidence interval 2.023-13.339; P = 0.001). Severity and intensity of atherosclerosis increases in COPD and atherosclerotic lesions have worse morphological properties in COPD.

The relation between chronic obstructive pulmonary disease and coronary collateral vessels.

Coronary collateral vessels can provide a perfusion reserve in case of increased myocardial oxygen demand. Development of coronary collateral vessels (CCV) is triggered by the pressure gradient between the coronary bed of arteries caused by an obstruction and myocardial ischemia. Myocardial hypoxia can facilitate development of CCVs. There is a chronic hypoxemia in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate the effect of COPD on CCVs. The study included 98 patients with COPD who underwent coronary angiography. Those patients in whom coronary angiography is normal or severity of coronary artery stenosis in thought not to be sufficient for the development of CCVs (<80%) were excluded from the study. A total of 98 patients (mean age, 62 +/-9 years) met the criteria for the COPD group. For case-control matching, 98 consecutive without COPD patients (mean age 62 +/-10) who had one or more diseased vessels with 80% or greater stenosis were included in the control group. The CCVs were graded according to the Rentrop scoring system, and the collateral score was calculated by summing the Rentrop numbers of every patient. The mean number of diseased vessels in patients with COPD and without COPD were 1.61 +/-0.69 and 1.77 +/-0.89 (p=0.155), respectively. The mean collateral score was 2.15 +/-2.03 in the COPD group and 1.32 +/-1.54 in the control group. After confounding variables were controlled for, the collateral score in patients with COPD group was significantly different from that in patients without COPD group (p=0.002). These findings suggest that CCV development is better in patients with COPD than in those patients without COPD. Thus, COPD may be an important factor affecting CCV development, which may be related to the presence of chronic hypoxemia in patients with COPD.

Chronic pulmonary disease in rural women exposed to biomass fumes.

INTRODUCTION: Biomass (organic) fuels cause indoor air pollution when used inside dwellings. We evaluated the frequencies of chronic obstructive pulmonary disease (COPD) and chronic bronchitis (CB) among rural women using biomass fuels for heating and cooking and compared them to women living in urban areas where such fuels are not used. METHODS: From electoral lists we randomly selected 242 women living in rural areas near Kayseri, Turkey and 102 women living in apartments in the city having central heating and cooking with fuels other than biomass ones. Using a translated version of the American Thoracic Society questionnaire, with additional questions from the British Medical Research Council questionnaire, trained interviewers conducted personal interviews. They also collected information on fuels used for cooking and heating. All study subjects underwent a physical examination and measurement of pulmonary function. RESULTS: We found that rural women were younger than urban women (mean age [and standard deviation], 40.5 [14.1] yr v. 43.6 [11.9] yr). More urban than rural women were current (14.7% v. 4.5%, p < 0.001) or past (11.8% v. 1.2%, p < 0.001) smokers. CB was more prevalent among rural women than urban women (20.7% v. 10.8%, p < 0.03). Similarly, COPD was more prevalent in rural women (12.4% v. 3.9%, p < 0.05). Although the pulmonary function tests were within normal limits, FEV, values in rural women were found to be relatively low compared with those of urban women (p < 0.05). INTERPRETATION: Rural women exposed to biomass fumes are more likely to suffer from CB and COPD than urban women even though the prevalence of smoking is higher among the latter group.

Antituberculosis drug resistance patterns in two regions of Turkey: a retrospective analysis.

BACKGROUND: The emergence of Mycobacterium tuberculosis strains resistant to antituberculosis agents has recently received increased attention owing largely to the dramatic outbreaks of multi drug resistance tuberculosis (MDR-TB). METHODS: Patients residing in Zonguldak and Kayseri provinces of Turkey with, pulmonary tuberculosis diagnosed between 1972 and 1999 were retrospectively identified. Drug susceptibility tests had been performed for isoniazid (INH), rifampin (RIF), streptomycin (SM), ethambutol (EMB) and thiacetasone (TH) after isolation by using the resistance proportion method. RESULTS: Total 3718 patients were retrospectively studied. In 1972-1981, resistance rates for to SM and INH were found to be 14.8% and 9.8% respectively (n: 2172). In 1982-1991 period, resistance rates for INH, SM, RIF, EMB and TH were 14.2%, 14.4%, 10.5%, 2.7% and 2.9% (n: 683), while in 1992-1999 period 14.4%, 21.1%, 10.6%, 2.4% and 3.7% respectively (n: 863). Resistance rates were highest for SM and INH in three periods. MDR-TB patients constituted 7.3% and 6.6% of 1982-1991 and 1992-1999 periods (p > 0.05). CONCLUSION: This study demonstrates the importance of resistance rates for TB. Continued surveillance and immediate therapeutic decisions should be undertaken in order to prevent the dissemination of such resistant strains.