Aerobic exercise is safe and effective in systemic sclerosis.

Several studies have established that systemic sclerosis patients have a reduced exercise capacity when compared to healthy individuals. It is relevant to evaluate whether aerobic exercise in systemic sclerosis patients is a safe and effective intervention to improve aerobic capacity. Seven patients without pulmonary impairment and seven healthy controls were enrolled in an 8-week program consisting of moderate intensity aerobic exercise. Patients and controls had a significant improvement in peak oxygen consumption (19.72+/-3.51 vs. 22.27+/-2.53 and 22.94+/-4.70 vs. 24.55+/-3.00, respectively, p=0.006), but difference between groups was not statistically significant (p=0.149). This finding was reinforced by the fact that at the end of the study both groups were able to perform a significantly higher exercise intensity when compared to baseline, as measured by peak blood lactate (1.43+/-0.51 vs. 1.84+/-0.33 and 1.11+/-0.45 vs. 1.59+/-0.25, respectively, p=0.01). Patients improved the peak exercise oxygen saturation comparing to the baseline (84.14+/-9.86 vs. 90.29+/-5.09, p=0.048). Rodnan score was similar before and after the intervention (15.84+/-7.84 vs.12.71+/-4.31, p=0.0855). Digital ulcers and Raynaud's phenomenon remained stable. Our data support the notion that improving aerobic capacity is a feasible goal in systemic sclerosis management. The long term benefit of this intervention needs to be determined in large prospective studies.

Reduced exercise capacity in systemic sclerosis patients without pulmonary involvement.

OBJECTIVE: To evaluate the exercise capacity of women with systemic sclerosis (SSc) without pulmonary involvement using a cardiopulmonary stress test. METHODS: Thirteen consecutive female SSc patients [mean age 40.8+/-14 years, mean body mass index (BMI) 25.5+/-3.7 kg/m2] without pulmonary and cardiac involvement and 13 healthy sedentary female controls (mean age 41.6+/-9.1 years, mean BMI 23.7+/-3.8 kg/m2) matched by age and BMI underwent a maximum cardiopulmonary stress test (Bruce protocol). The following parameters were analysed: peak oxygen uptake (VO2peak), anaerobic threshold (AT), respiratory compensation point (RCP) and metabolic equivalent (MET) of the VO2peak. Comparisons between groups were analysed using the Student t-test. RESULTS: Forced vital capacity (FVC; 92.2+/-14.2% predicted) and carbon monoxide diffusion lung capacity (DL CO; 85.8+/-5.8% predicted) were within the normal range in SSc patients. VO2peak of SSc patients was significantly reduced in comparison to the control group (19.8+/-4.6 vs. 23.7+/-4.5 mL/kg/min, p = 0.04). SSc patients also had a significant reduction in MET at peak exercise (5.6+/-1.3 vs. 6.7+/-1.3 MET, p = 0.04) and a significant shorter time interval between AT and RCP compared to the control group (112.6+/-95.6 vs. 164.0+/-65.3 s, p = 0.03). CONCLUSION: SSc patients without pulmonary impairment have reduced exercise capacity. Abnormal vascular response to exercise may account for this finding, as the vascular system is one of the major target organs in this pathological condition.

[The surgical treatment of nodal reentry tachycardia. The late results]. / Tratamento cirúrgico da taquicardia por reentrada nodal. Resultados tardios.

PURPOSE: To analyze the long-term results of surgical treatment of atrioventricular nodal reentrant tachycardia (AVNT). METHODS: From March 1987 to March 1990, 20 patients with AVNT were submitted to surgical therapy, 14 female, aged 12 to 70 (42.8 +/- 17) years. All presented crisis of AVNT from 6 months to 60 (18.4 +/- 15.9) years. Ten of them had syncope or near syncope and two with cardiac arrest during reversion of AVNT with antiarrhythmic drugs. They used 1 to 6 (3.75 +/- 1.45) antiarrhythmic drugs before surgery. The electrophysiologic study (EPS) showed the common form of AVNT in all cases. The surgical procedure was anatomically directed to the posterior area of the AV node. Programmed atrial stimulation (PAS) were applied on 18 patients after surgery. The long-term results were analysed by clinical evaluation, EPS and Holter when they were necessary. RESULTS: The postoperative PAS was done in 18 patients and did not induce any AVNT, even after atropine IV. The PR interval was 153 +/- 50 ms before and 152 +/- 38 ms after surgery (p > 0.05). During follow up (26 +/- 10 m) there were not AVNT recurrence. Two patients developed chronic atrial fibrillation after 24 months of surgery. CONCLUSION: The perinodal dissection technique used was safe and successful to treat AVNT, preserving AV nodal conduction.

New trypsin-releasable spasmogenic substances in the plasma of spontaneously hypertensive rats

We measured the levels of trypsin-releasable spasmogenic substances (TRSS) in the plasma of spontaneously hypertensive rats (SHR) during the development of hypertension. TRSS levels (x ñ SEM, N = 4) were significantly higher at 12 weeks (7.13 ñ 1.05 microng bradykinin equivalents (BKE)/ml plasma) and 24 weeks (6.87 ñ 0.60 microng BKE/ml) compared to 8 weeks (3.3 ñ 0.55 microng BKE/ml) and to normotensive Wistar Kyoto (WKN) rats, whose levels were 3.74 ñ 0.74 microng BKE/ml at 24 weeks and did not change significantly during the period studied. The mean arterial pressure (MAP) of SHR was 150-170, 160-180 and 170-220 mmHg at 8, 12 and 24 weeks, respectively, whereas the WKN MAP was 110-120 mmHg at 24 weeks. The increase in total TRSS was due to substances which elicit the slow contraction of the isolated guinea pig ileum and which could be distinguished from BK, T-kinin and other BK homologues by gel filtration on Sephadex G-25, gradient elution chromatography on CM-cellulose and by the slow rate of contraction of the guinea pig ileum. All of these properties are the same as those we have previously demonstrated for TRSS of Goldblatt 1-kidney 1-clip renal hypertensive rats and which are due, at least in part, to a 14 amino acid peptide whose composition does not correpond to any known spasmogenic substance

New trypsin-releasable spasmogenic substances in the plasma of spontaneously hypertensive rats.

We measured the levels of trypsin-releasable spasmogenic substances (TRSS) in the plasma of spontaneously hypertensive rats (SHR) during the development of hypertension. TRSS levels (means +/- SEM, N = 4) were significantly higher at 12 weeks (7.13 +/- 1.05 micrograms bradykinin equivalents (BKE)/ml plasma) and 24 weeks (6.87 +/- 0.60 micrograms BKE/ml) compared to 8 weeks (3.3 +/- 0.55 micrograms BKE/ml) and to normotensive Wistar Kyoto (WKN) rats, whose levels were 3.74 +/- 0.74 micrograms BKE/ml at 24 weeks and did not change significantly during the period studied. The mean arterial pressure (MAP) of SHR was 150-170, 160-180 and 170-220 mmHg at 8, 12 and 24 weeks, respectively, whereas the WKN MAP was 110-120 mmHg at 24 weeks. The increase in total TRSS was due to substances which elicit the slow contraction of the isolated guinea pig ileum and which could be distinguished from BK, T-kinin and other BK homologues by gel filtration on Sephadex G-25, gradient elution chromatography on CM-cellulose and by the slow rate of contraction of the guinea pig ileum. All of these properties are the same as those we have previously demonstrated for TRSS of Goldblatt 1-kidney 1-clip renal hypertensive rats and which are due, at least in part, to a 14 amino acid peptide whose composition does not correspond to any known spasmogenic substance.

Evidence for new spasmogenic substances released by trypsin from plasma of normotensive and hypertensive rats.

We have extended our previous study of increased levels of new spasmogenic substances released by trypsin from the plasma of chronic one-kidney, one-clip hypertensive rats by describing preparative procedures utilizing Sephadex G-25, CM-cellulose and C18 reverse-phase HPLC for their partial purification. We demonstrate the existence of at least 6 HPLC components, distinguishable from bradykinin, bradykinin homologues having Lys before Arg1 of bradykinin and T-kinin (Ile-Ser-bradykinin) on the basis of their chromatographic properties. Several of these spasmogenic substances induce a very slow contraction of the isolated guinea pig ileum when compared to bradykinin.

Increased levels of new spasmogenic substances released by trypsin from plasma of hypertensive rats.

The present study was undertaken to evaluate the participation of the kallikrein-kinin system in the normalization of blood pressure after release of the clip in one-kidney, one clip hypertensive rats ( 1K1C ). Kininogen was determined before and after unclipping by tryptic digestion of denatured rat plasma, and spasmogenic activity was measured with isolated guinea pig ileum. In contrast to human plasma for which bradykinin (BK) is the only trypsin-releasable spasmogenic substance ( TRSS ), rat plasma contains non-BK TRSS (Fractions P1 and P2) as well as BK. Fractions P1 and P2 were separated from BK by SP-Sephadex chromatography. An increase of total TRSS was demonstrated 60 days after clipping and reached a maximum at approximately Day 75, which was two times that of the normotensive controls (NC). The level of total TRSS did not change after unclipping . The increased level of TRSS in the hypertensive state confirmed the observations of other investigators who reported increased kininogen levels but who could not distinguish between BK and non-BK TRSS because bioassays were performed without prior chromatographic separation of the spasmogenic activities. Fractions P1 and P2 were present in the TRSS of both 1K1C and NC plasma, but were two to six times higher in 1K1C and thus probably accounted quantitatively for the increased TRSS in 1K1C . The data suggest that in the hypertensive state there is an alteration in the relative amounts of some plasma proteins that contain non-BK TRSS within their amino acid sequences. Fractions P1 and P2 also contain potentiating peptides and have not yet been purified to homogeneity.(ABSTRACT TRUNCATED AT 250 WORDS)