TY - JOUR AU - Settakis, G AU - Páll, Dénes AU - Molnár, Csilla AU - Bereczki, Dániel AU - Csiba, László AU - Fülesdi, Béla TI - Cerebrovascular reactivity in hypertensive and healthy adolescents: TCD with vasodilatory challenge JF - JOURNAL OF NEUROIMAGING J2 - J NEUROIMAGING VL - 13 PY - 2003 IS - 2 SP - 106 EP - 112 PG - 7 SN - 1051-2284 DO - 10.1177/1051228403251265 UR - https://m2.mtmt.hu/api/publication/1052876 ID - 1052876 AB - BACKGROUND: Adolescent hypertension predicts hypertension and increased cardiovascular morbidity in adulthood. The aim of the present work was to test whether cerebrovascular reactivity to CO2 is altered among hypertensive adolescents. METHODS: From the population-based cohort of the Debrecen Hypertension Study, 113 hypertensive and 58 normotensive adolescents underwent transcranial Doppler measurements at rest and after 30 seconds of breath holding. RESULTS: Systolic, mean, and diastolic blood flow velocities were higher among hypertensive individuals at rest. Taking the absolute blood flow velocity parameters into account, after breath holding, only the pulsatility index was significantly higher in the hypertensive group. The percentage change of the different blood flow parameters showed less intensive change in hypertensive teenagers. CONCLUSION: Cerebral vasoreactivity is decreased among hypertensive individuals as compared to healthy controls. LA - English DB - MTMT ER - TY - JOUR AU - Settakis, G AU - Lengyel, A AU - Molnár, Csilla AU - Bereczki, Dániel AU - Csiba, László AU - Fülesdi, Béla TI - Transcranial Doppler study of the cerebral hemodynamic changes during breath-holding and hyperventilation tests JF - JOURNAL OF NEUROIMAGING J2 - J NEUROIMAGING VL - 12 PY - 2002 IS - 3 SP - 252 EP - 258 PG - 7 SN - 1051-2284 DO - 10.1177/10528402012003007 UR - https://m2.mtmt.hu/api/publication/1052898 ID - 1052898 AB - BACKGROUND AND PURPOSE: The aim of the present study was to assess the time course of hyperventilation (HV) and breath-holding (BH) tests in healthy volunteers. SUBJECTS AND METHODS: Young healthy volunteers (n = 29) underwent continuous registration of the middle cerebral artery mean blood flow velocity (MCAV) during and after 30 seconds of BH and 60 seconds of HV. Absolute values as well as percentage changes of the MCAV are reported. In 13 subjects, determination of capillary blood gas parameters (pH, pCO2, pO2, and O2 saturation) was performed before tests, after BH and after HV. RESULTS: MCAV during 30 seconds of breath-holding starts to increase after 10 seconds and reaches its highest level at 30 seconds. After breathing normally, MCAV normalizes within 30 seconds. Hyper-ventilation results in a decrease in MCAV, which reaches a plateau at 20 to 30 seconds after starting to hyperventilate, and blood flow velocity did not change significantly any further until the end of the procedure. The normalization of the MCAV is incomplete at 30 seconds after finishing hyperventilation. None of the capillary blood gases changed significantly after breath-holding, whereas capillary pH, pO2, and oxygen saturation increased and pCO2 decreased after hyperventilation. No relationship was found between capillary blood gas parameters and MCAV values. CONCLUSIONS: The authors concluded that breath-holding and hyperventilation tests seem to be a practical alternative to acetazolamide and the CO2 inhalation method in the assessment of cerebral hemodynamics. LA - English DB - MTMT ER - TY - JOUR AU - Fülesdi, Béla AU - Limburg, M AU - Bereczki, Dániel AU - Káplár, Miklós AU - Molnár, Csilla AU - Kappelmayer, János AU - Neuwirth, G AU - Csiba, László TI - Cerebrovascular reactivity and reserve capacity in type II diabetes mellitus JF - JOURNAL OF DIABETES AND ITS COMPLICATIONS J2 - J DIABETES COMPLICAT VL - 13 PY - 1999 IS - 4 SP - 191 EP - 199 PG - 9 SN - 1056-8727 DO - 10.1016/S1056-8727(99)00044-6 UR - https://m2.mtmt.hu/api/publication/1052918 ID - 1052918 AB - The aim of the study was to test the hypothesis that cerebrovascular reserve capacity and cerebrovascular reactivity are impaired in patients suffering from non insulin-dependent diabetes mellitus. We also intended to investigate factors which may influence resting cerebral blood flow velocity and cerebrovascular reserve capacity. A total of 28 patients suffering from type II diabetes mellitus and 20 healthy control subjects were studied. Based on diabetes duration patients were divided into two groups: subjects with > 10 years and those with < or = 10 years disease duration. Middle cerebral artery mean blood flow velocities were measured at rest and after intravenous administration of 1g acetazolamide. Cerebrovascular reactivity and reserve capacity were calculated. Blood glucose, insulin, glycosylated hemoglobin, hemostatic factors (fibrinogen, alpha-2 macroglobulin and von Willebrand factor antigen) were determined. Cerebrovascular reactivity and reserve capacity values were compared between the two diabetic subgroups and controls. Correlations between laboratory parameters and cerebrovascular reserve were investigated by linear regression analysis. Resting cerebral blood flow velocity was similar in controls and in the two diabetic subgroups. Cerebrovascular reactivity was elevated for a shorter time in patients with > 10 years disease duration than in controls and short-term diabetic patients. Cerebrovascular reserve capacity was lower in the long-term diabetes group (means +/- SD: 39.6 +/- 20.7%) than in patients with < or = 10 years disease duration (63.3 +/- 17.4%, p < 0.02 after Bonferroni correction). Cerebrovascular reserve capacity was inversely related to the duration of the disease (R = 0.53, p < 0.003). None of the determined laboratory factors had any relation with resting cerebral blood flow and cerebrovascular reserve capacity. The vasodilatory ability of cerebral arterioles is diminished in long-standing type II diabetes mellitus. LA - English DB - MTMT ER -