Biomedical subjects

G Ramaswami

Publications and source records attributed to G Ramaswami.

At least 37 records · Page 2Linked to original sources

PubMed1997

Circadian pattern of post-surgical fatal pulmonary embolism.

BACKGROUND: The circadian distribution of fatal pulmonary thromboembolism in general surgical patients is unknown. PATIENTS AND METHODS: One hundred consecutive cases of pulmonary embolism, with reliable clinical notes and data, were studied (67 men and 33 women; mean age 71 years). Only post-surgical cases were considered in this analysis. Patients had undergone elective (78%) or emergency abdominal surgery (22%). Correct prophylaxis (according to the Windsor Consensus Statement) had been used in 12%. Cases were grouped according to the time of onset of signs and symptoms related to pulmonary embolism at one hour intervals. RESULTS: The maximum incidence of fatal pulmonary embolism was between 7.00 a. m. and 1.00 p. m. with the highest peaks at 9.00 and 11.00 a. m. 9% of deaths) (P < 0.02). When results from this study were compared to a previous study no significant difference was observed between the distribution profile of cases from general medical wards and surgical wards. CONCLUSION: It appears that in surgical patients there is a circadian pattern in pulmonary embolism as already documented in medical patients.

Aged↗

PubMed1996

The role of the distribution and anatomic extent of reflux in the development of signs and symptoms in chronic venous insufficiency.

PURPOSE: The purpose of this study was to identify the distribution of venous reflux in patients with different patterns of reflux with each class. METHODS: Color-flow duplex imaging was used to evaluate the entire venous system from groin to ankle in 465 patients (594 limbs) belonging to different clinical CVI classes (0, 1, 2, and 3). A history of previous superficial thrombophlebitis was present in five limbs and past deep vein thrombosis in 70. RESULTS: One hundred seventy eight (30%) limbs were normal and the remaining 416 (70%) had venous incompetence. Deep reflux was present exclusively in 19 limbs (3.2%), and the perforation system alone was involved in only three limbs (0.5%). However, isolated superficial incompetence was seen in 186 limbs (31.3%) and a combination of superficial with perforating alone was involved in 45 (7.6%). Incompetence in all three systems was seen in 99 extremities (16.7%). In addition, the superficial system was involved in 390 limbs, the perforators in 151, and the deep system in 178 limbs. Only a small percentage of those in class 0 had reflux, and most of them had a single site of incompetence. In class 1 the majority of the limbs had superficial reflux (90.3%), 10.3% of the limbs had deep venous reflux, and 6.9% were competent. Reflux in the superficial system was only seen in 80.7% of the limbs in class 1 and in one fifth of the limbs in classes 2 and 3. Isolated deep or perforated incompetence was rare in all classes. Variable combined patterns of reflux were seen more often in classes 2 and 3 (p < 0.0001). In classes 2 and 3 there were no differences in the number of incompetent sites in the superficial and deep venous systems or the patterns of reflux (p > 0.1). The number of incompetent perforators in class 3 tended to be higher than that in class 2, especially in the below-knee segment, but no significant differences were seen. Distal reflux was present in the majority of the limbs in all symptomatic classes (1, 2, and 3). CONCLUSIONS: The distribution and extent of reflux is strongly associated with clinical severity of CVI through class 2. Distal venous reflux is present in at least 80% of the symptomatic limbs. Deep venous thrombosis may not be a prerequisite for the development of skin changes or ulceration in about 75% of the limbs. Superficial venous surgery could be beneficial to at least one third of patients with skin changes or ulceration.

Adult↗

PubMed1996

Changes in energy metabolism of calf muscle in patients with intermittent claudication assessed by 31P magnetic resonance spectroscopy: a phase II open study.

Energy status and metabolism in skeletal muscle of nine patients with peripheral arterial disease and suffering from intermittent claudication were evaluated using 31phosphorus magnetic resonance spectroscopy (MRS) before and after treatment for 3 months with propionyl-L-carnitine (PLC; 2 g/day p.o.). Maximum walking distance (MWD) was assessed on a standard treadmill (4 km/h, zero incline). For the group as a whole 31P MRS results did not change significantly with PLC. Although MWD increased by a mean of 36%, this change did not reach significance. However, when these variables were assessed with respect to the change in MWD, there were significant differences between those who increased MWD by > 30% (responders, R; n = 5) and those who did not (nonresponders, NR; n = 4). Compared with pretreatment values, during exercise the decrease in muscle pH in R relative to the decrease in phosphocreatine was less after PLC (p = 0.04). After exercise there was a significant inverse correlation between the changes in recovery half-time (t1/2) for phosphocreatine and in MWD (r = -0.91, p = 0.01). With PLC, Vmax increased in R (p = 0.04), but not in NR. For the patient group as a whole, the changes in Vmax and MWD correlated positively (r = 0.90, p = 0.01). This study helps to identify the changes in muscle metabolism that correlate with changes in exercise performance, and may accompany treatment with PLC.

Adenosine Diphosphate↗

PubMed1996

Principles of angioplasty guidance using ultrasound.

Marker bands that cast dense shadow on X-ray are placed at crucial points on a catheter (for example on a peripheral angioplasty catheter on either side of the balloon) so that those parts of the catheter can be guided inside the body by X-ray. For catheter guidance by ultrasound, an ultrasound sensor in the mid-balloon region of an angioplasty catheter is integrated to the scanhead of an ultrasound scanner, via a catheter system interface (CSI). When the sensor in the catheter is imaged by the ultrasound scanner, the CSI injects a bright arrow corresponding to its position. This allows accurate catheter guidance using ultrasound. This paper describes the principles of ultrasound guidance of catheters and the initial clinical experience using this new catheter system (Echomark) in carrying out peripheral transluminal angioplasty.

Angioplasty↗

PubMed1996

Vasa vasorum visualised by power-Doppler in normal and arteriosclerotic carotid arteries.

Vasa vasorum and the perfusion of the carotid wall in normal arteries and in arteries with arteriosclerotic plaques was evaluated in-vivo using power-Doppler. Two types of arteries were studied using high-resolution ultrasound. These were arteries with a normal wall (intima, media and adventitia clearly separated) and arteries with intima-media thickening and plaques without calcification. In 10 normal subjects and in 10 patients with early plaques vasa vasorum were visualised. On power-Doppler they appeared as distinct, glomerular-like perfusion units, regularly placed along the course of normal arteries and at similar distance (2 to 4 mm from the lumen-wall interface, within the adventitia and periadventitia layers). In arteriosclerotic vessels the distribution of vasa vasorum units was more irregular, often concentrated in one spot with some perfusion units more distant from the lumen (between 2.5 and 5 mm) and their pulsatility was reduced. Flow velocity complex in most vasa vasorum was comparable, in lower scale to the pattern observed in the carotid lumen without significant differences between normal and arteriosclerotic arteries. The average peak systolic flow velocity was 15: +/-4 cm/sec and the average diastolic velocity was 6 +/- 4 in normal arteries with a median pulsatility index of 1.8 (range 2.2-1.05); in arteriosclerotic arteries velocities were 13 +/- 4 (peak systolic) and 3 +/- 2 (end diastolic) with a median pulsatility index of 1.71 (range 2.1-1.1). In conclusion a different, apparent distribution of vasa vasorum was observed in normal carotids and in carotids with arteriosclerotic lesions.

Adult↗

PubMed1995

New insights into the pathophysiologic condition of venous ulceration with color-flow duplex imaging: implications for treatment?

PURPOSE: This study was conducted to investigate the distribution of reflux in the veins adjacent to or within the venous ulcer (local) and to correlate it with the pattern of disease of the axial veins (all veins away from the ulcer area) of the affected limb. METHODS: Forty-three ulcers in 34 legs of 33 patients were examined with color-flow duplex imaging. The veins in the area of the ulcer were scanned with a sterile technique. RESULTS: In 17 legs (50%) there was documented past deep venous thrombosis. All of the 34 limbs had reflux in the superficial or deep axial veins either alone or in combination. Fifteen of these limbs (44%) also had perforating vein incompetence, but none had perforator incompetence alone. Six ulcers showed no evidence of reflux in the local veins when scanned through the ulcer bed despite the presence of reflux in the axial veins of the limb. In 13 limbs with 17 ulcers, either the superficial axial veins alone or the deep axial veins alone were affected (with or without associated perforator incompetence). Examination of the local veins associated with these 17 ulcers revealed a similar pattern of reflux to that seen in the axial veins in 13 cases, with the remaining 4 ulcers showing no local venous abnormality. The pattern of reflux was less predictable at the local ulcer level in limbs where both superficial and deep venous incompetence coexisted in the axial veins. Only 7 of the 26 ulcers (27%) in these limbs had similar evidence of combined superficial and deep reflux in the local ulcer veins, whereas 10 ulcers (39%) were associated with local reflux in the superficial or deep veins alone. CONCLUSIONS: These data show that 86% (37/43) of the ulcers has some degree of reflux in the local area, the pattern of which may differ from the axial vein disease. Treatment of the local hemodynamic abnormalities may be an important factor in the healing of the ulcers and in the prevention of their recurrence.

Adolescent↗

PubMed1995

Calf muscle mitochondrial and glycogenolytic ATP synthesis in patients with claudication due to peripheral vascular disease analysed using 31P magnetic resonance spectroscopy.

1. We set out to define abnormalities of oxidative ATP synthesis, cellular proton efflux and the efficiency of ATP usage in gastrocnemius muscle of patients with claudication due to peripheral vascular disease, using data obtained by 31P magnetic resonance spectroscopy during aerobic exercise and recovery. 2. Eleven patients with moderate claudication were studied and results were compared with 25 age-matched control subjects. Changes in pH and phosphocreatine concentration during recovery were used to calculate the maximum rate of oxidative ATP synthesis (Qmax.) and the capacity of net proton efflux. Changes in pH and phosphocreatine concentration were used to estimate rates of non-oxidative and (indirectly) oxidative ATP synthesis throughout exercise, taking account of abnormalities in proton efflux during exercise. 3. In patients with claudication, slow post-exercise phosphocreatine recovery showed a 42 +/- 9% decrease in Qmax., and the slow ADP recovery was consistent with this. pH recovery was slow, showing a 77 +/- 9% decrease in the capacity for proton efflux. Both abnormalities are compatible with a substantial reduction in muscle blood flow. 4. During exercise, increased phosphocreatine depletion and intracellular acidification were a consequence of impaired oxidative ATP synthesis and the consequent increase in non-oxidative ATP synthesis, compounded by reduced proton efflux. The acidification prevented an increase in ADP concentration which could otherwise partially compensate for the oxidative defect. All these abnormalities are compatible with a reduced muscle blood flow. 5. In addition, initial-exercise changes in pH and phosphocreatine concentration implied a 44 +/- 5% reduction in 'effective muscle mass', necessitating an ATP turnover (per litre of muscle water) twice as high for given power output as in control muscle. Some of this is probably due to a localized loss of muscle fibres, but the rest appears to reflect reduced metabolic efficiency of the muscle. This is not a direct consequence of reduced blood flow, and may be related to change in muscle fibre type.

Adenosine Triphosphate↗

PubMed1995

Peripheral transluminal angioplasty under ultrasound guidance: initial clinical experience and prevalence of lower limb lesions amenable to ultrasound-guided angioplasty.

PURPOSE: Currently, endovascular techniques require monitoring by radiographic imaging for accurate catheter placement. The aim of this study was first to determine the feasibility of angioplasty under ultrasound guidance using a special catheter system. Based on this outcome, the second goal was to investigate the prevalence of lesions amenable to ultrasound-guided angioplasty. METHODS: A balloon catheter system (Echomark) has been developed, which allows accurate catheter guidance by ultrasound imaging. An ultrasound-sensitive piezoelectric sensor positioned in the middle of the balloon portion of the angioplasty catheter is interfaced to an external duplex scanner via the catheter system. The exact position of the balloon relative to the transducer is calculated and reproduced on the screen of the duplex scanner to guide balloon positioning. In the feasibility assessment of the procedure, 16 patients with disabling claudication and rest pain were selected for balloon angioplasty under ultrasound guidance based on arteriographic and hemodynamic lesion criteria of > 50% stenosis with a peak systolic velocity ration > 2.5 in a lesion < 4 cm long that could be imaged by duplex ultrasonography. A fall in the peak systolic velocity ratio below 2.0 was selected for a procedural endpoint corresponding to < 30% residual stenosis on the completion angiogram. In the second part of the study, the prevalence of stenoses amenable to ultrasound-guided angioplasty was studied in 80 patients presenting with symptoms of peripheral arterial disease. RESULTS: In the feasibility study, 20 stenoses (5 common iliac, 6 external iliac, and 8 superficial femoral arteries and 1 graft) meeting the inclusion criteria were subjected to ultrasound-guided angioplasty with confirmation by completion angiography. The procedure was possible in 18 (90%) of the 20 stenoses. The two failures occurred in iliac arteries that could not be imaged by duplex scanning due to obesity, bowel gas, and/or vessel wall calcification. In one case, the peak systolic velocity ratio exceeded 2.5 despite a satisfactory control arteriogram; redilation was performed, and the ratio fell below 2.0. In the second part of the study, 21 (26.2%) of the 80 patients had 29 stenoses that were amenable to angioplasty according to angiographic criteria (> 50% stenosis and < 4 cm length). All these stenoses were evaluated with duplex scanning to determine their suitability for angioplasty under ultrasound guidance. Twenty-three (79%) of the 29 lesions selected for angioplasty were well visualized by duplex, and angioplasty would have been possible based on our initial clinical experience. CONCLUSIONS: Angioplasty under ultrasound control is a feasible technique for peripheral lesions. Ultrasound allows monitoring of both anatomical and hemodynamic parameters during angioplasty and thus provides a procedural endpoint that correlates to the control angiogram. A large proportion (79%) of stenoses deemed suitable for angioplasty can be well visualized by ultrasound, but obesity, vessel wall calcification, and bowel gas may limit the ability to obtain a satisfactory ultrasound image. Ultrasound-guided angioplasty is a potentially useful procedure that warrants further investigation.

Angioplasty, Balloon↗

PubMed1994

Ultrasonic carotid artery plaque structure and the risk of cerebral infarction on computed tomography.

PURPOSE: The North American and the European Symptomatic Carotid Endarterectomy Trial investigators reported a conclusive benefit of carotid endarterectomy for patients with symptomatic 70% to 99% internal carotid artery (ICA) stenosis. However, it has been suggested that plaque structure may be an even more important factor in producing stroke than the degree of stenosis. The aim of this study was to test the hypothesis that the ultrasonic characteristics of carotid artery plaques were closely related to symptoms and to the prevalence of cerebral infarcts on computed tomography (CT). METHODS: One hundred five carotid artery plaques causing greater than 70% stenosis in the ICA in 83 consecutive patients who underwent brain CT were characterized into four ultrasonic types: echolucent plaques, predominantly echolucent plaques, predominantly echogenic plaques, and echogenic plaques. Patients with permanent neurologic deficit were excluded. RESULTS: There was a significant ipsilateral association between type 1 plaques and symptomatic hemispheres (p < 0.002). Twenty-six of the 105 cerebral hemispheres assessed by CT had infarcts. There was an increased incidence of brain infarcts in type I plaques (37%) compared with 18% in types II, III, and IV combined (p < 0.02). CONCLUSION: Our results support the hypothesis that echolucent plaques are more frequently associated with symptoms and cerebral infarctions and provide further evidence that these plaques are unstable and tend to embolize. Studies on the natural history of asymptomatic carotid artery stenosis should investigate whether plaque characterization could identify a high-risk group.

Arteriosclerosis↗

PubMed1994

Duplex controlled angioplasty.

Duplex examination was carried out to assess lesions in peripheral arteries amenable to angioplasty. With the help of a special catheter, angioplasty of these lesions was performed under Duplex control. Sixteen patients presenting with claudication were examined by Duplex and 38 lesions were identified (31 stenoses, seven occlusions) and all the findings except one (vessel E1) were confirmed by subsequent angiography. Sixteen lesions were considered amenable to angioplasty and 13 lesions (in 10 patients) were selected for Duplex controlled angioplasty. A new catheter system which has a piezo-electric transducer at the centre of the balloon and integrated to a Duplex scanner via a catheter system interface, was used for the procedure. This allows the exact position of the balloon to be represented on the screen. Thirteen lesions (seven superficial femoral artery (SFA), three external iliac, two common iliac and one graft) were subjected to angioplasty under Duplex control. In one patient, the SFA was punctured directly under ultrasound control as the profunda was diseased. The guide wire was visualised in all cases and in the majority of cases, balloon size for the angioplasty was chosen by measurement of the arterial diameter by Duplex, which was also used for haemodynamic evaluation before, during and after the procedure. Eleven lesions (85%) underwent angioplasty entirely under Duplex control and additional X-ray control was needed in only two cases. In conclusion, Duplex allows the monitoring of both anatomical and haemodynamic parameters during angioplasty. It also reduces the risk of ionising radiation. Our initial experience has been encouraging as angioplasty was performed in the majority of lesions purely under Duplex control.

Angioplasty, Balloon↗

PubMed1993

Characterization of symptomatic and asymptomatic carotid plaques using high-resolution real-time ultrasonography.

High-resolution ultrasonography was used to classify carotid plaques into five different types in 72 patients with symptoms and in 49 without, and with stenosis of the origin of the internal carotid artery > 70 per cent. There were 72 plaques in the symptomatic group and 75 in the asymptomatic group. Type 1 plaques were uniformly echolucent, type 2 predominantly echolucent, type 3 predominantly echogenic, type 4 uniformly echogenic and type 5 consisted of plaques that could not be classified owing to heavy calcification and acoustic shadows. Type 1 plaque was found in 90 per cent of patients with symptoms and in 10 per cent of those without, type 2 plaque was found in 53 and 47 per cent, type 3 in 34 and 66 per cent, and type 4 in 5 and 95 per cent, respectively. The preponderance of echolucent plaques in symptomatic patients with stenosis > 70 per cent supports the hypothesis that this type of plaque is unstable and tends to embolize. In contrast, in patients without symptoms there is preponderance of echogenic plaques.

Arteriosclerosis↗

PubMed1993

Ultrasonic classification of carotid plaques causing less than 60% stenosis according to ultrasound morphology and events.

Carotid plaque morphology studied by ultrasound has been used to classify 3 types of bifurcation plaques, producing less than 60% stenosis on duplex scanning: Type A, the homogeneous, highly echogenic plaque; Type B, the heterogeneous (mainly echogenic, B-1 or mainly echolucent, B-2) plaque; Type C, the complex plaque with irregular surface, echogenic and/or echolucent with calcifications. One hundred asymptomatic subjects in each plaque group were included in a prospective 4-year follow-up study to evaluate clinical events and brain damage by yearly cerebral CT and MR scans. After four years 96 subjects with type A plaque, 89 with type B-1 and 67 with type C plaques completed the study. While there were no clinical events or positive cerebral scans in subjects with type A plaques there was a significantly increasing number of cerebral and vascular events in subjects with plaque B and C type with a zero mortality in the plaque A group, a 2.24% mortality in type B plaques and a significantly higher (p > 0.05) mortality (13.4%) in type C plaques. CT and MR scans revealed brain damage which had been totally asymptomatic with MR detecting a larger number of lesions. Also the number of cerebral lesions observed by CT/MR were significantly greater than the number of recorded clinical episodes. ECG stress test revealed a larger number of asymptomatic coronary disease in the C type plaques. In conclusion ultrasound plaque morphology is linked to different incidences of cerebral and cardiac events, brain damage and asymptomatic coronary disease. Also CT and MR may reveal lesions which do not cause signs or symptoms.

Aged↗

PubMedDate not supplied

Arterial wall changes in type 2 diabetic subjects.

Arterial ultrasonic appearances using high resolution ultrasound were studied in 97 subjects with Type 2 diabetes and age- and sex-matched controls. The intima-media thickness of both common carotid arteries was measured 2 cm proximal to the bifurcation and the presence or absence of plaque on both common and femoral bifurcations was recorded. The mean intima-media thickness in subjects with diabetes was 0.82 +/- 0.22 mm while in the controls 0.66 +/- 0.13 mm (p < 0.001). Multiple regression in diabetic subjects only showed no correlation between age, sex, body mass index, smoking, duration of diabetes, systolic or diastolic blood pressure, cholesterol, HDL, LDL, triglycerides, HbA1 and the common carotid artery intima-media thickness. Type 2 diabetes is associated with increased intima-media thickness which has been found to be a marker of cardiovascular events in the general population.

Arteriosclerosis↗

PubMedDate not supplied

Treatment of severe intermittent claudication with pentoxifylline: a 40-week, controlled, randomized trial.

The efficacy, safety, and cost of pentoxifylline (PXF) in the treatment of severe intermittent claudication were studied comparing PXF and placebo in a randomized 40-week study. A treadmill test was performed at inclusion and at the end of weeks 20 and 40. A progressive training plan and the control of risk factors (with antiplatelet treatment) were used in both groups. Of the 200 included patients, 178 completed the study: 88 in the PXF group and 90 in the placebo group. There were 22 dropouts. The two groups were comparable for age, sex distribution, and for the presence of risk factors and smoking. There was a significant increase in pain-free walking distance (PFWD) in both groups. The absolute and percent increase in PFWD was significantly greater in the PXF group (p<0.05). At 20 weeks, the increase was 360.5% in the PXF vs 252% in the placebo group. At 40 weeks, the increase was 386% in the PXF and 369% in the placebo group (p<0.02). Total walking distance (TWD) increased at 20 weeks (up to 254%) and up to 329% at 40 weeks. In the placebo groups the increase was 158% at 20 weeks and 183% at 40 weeks. The excess increase produced by PXF treatment was 30% at 20 weeks and 38% at 40 weeks (p<0.02). Unwanted effects treatment was well tolerated. No serious drug-related side effects were observed. In summary, between-group analysis favors PXF considering walking distance and costs. Results indicate good efficacy and tolerability.

Aged↗

PubMedDate not supplied

Treatment of long-distance intermittent claudication with pentoxifylline: a 12-month, randomized trial.

The efficacy, safety, and cost of pentoxifylline (PXF) in long-range (>400 m interval) intermittent claudication was studied comparing PXF and placebo in a 12-month study. A standardized treadmill test was performed at inclusion and at 6 and 12 months. A training plan based on walking was associated with the control of risk factor levels. Of the 194 included patients, 135 completed the study: 75 in the PXF group and 60 in the placebo group. There were 59 dropouts (due to low compliance). The authors observed a 148% increase in total walking distance (TWD) at 6 months with PXF (vs 110% with placebo; p<0.05); at 12 months, the increase was 170% with PXF (vs 131% with placebo; p<0.02). There was a 38% difference at 6 months and 39% at 12 months in favor of PXF. Treatment was well tolerated. In conclusion, PXF improved walking distance significantly better than placebo.

Aged↗

PubMedDate not supplied

Treatment of vascular inner ear disease with pentoxifylline: a 4-week, controlled, randomized trial.

The efficacy of pentoxifylline (PXF) in vascular inner ear disease (VIED) was studied comparing PXF and placebo in a 4-week study; 60 patients with unilateral loss of hearing, vertigo, dizziness, tinnitus (analyzed with an analogue scale line), and cochlear flow reduction were included. The aim of the study was to study the effect of PXF (1800 mg/day) in VIED considering clinical outcome and cochlear flow. All patients completed the study. Improvement in cochlear flow (p<0.05) and a decrease in score in both groups were observed. The cochlear flow increase was 287.5% in the PXF group vs 168% in the placebo group (119.5% difference; p<0.02). There was a difference in score decrease (44.1% larger) in the PXF group (p<0.05). PXF was more effective considering flow and symptoms.

Cochlea↗

PubMedDate not supplied

Treatment of vascular inner ear disease in vascular patients with pentoxifylline: a controlled, randomized trial.

The efficacy of Pentoxifylline in vascular inner ear disease (VIED) was studied comparing PXF and placebo in a 4-week study; 40 patients with vascular disease and monolateral loss of hearing, vertigo, dizziness, tinnitus (analyzed with an analogue scale line), and cochlear flow reduction were included. The aims of the study were to study the effects of PXF (1600 mg daily) in VIED considering clinical outcome and cochlear flow. Of the 20 included patients, 19 completed the study. One dropout in the placebo group was due to low compliance. Intention-to-treat analysis indicated an improvement in cochlear flow (p<0.05) and a decrease in score in both groups. The cochlear flow increase was 287.5% in the PXF group vs 168% in the placebo group (119.5% difference; p<0.02). There was a difference in score decrease (44.1% larger) in the PXF group (p<0.05).Between-group analysis favors PXF considering blood flow and symptoms. Results indicate good efficacy and tolerability of PXF in VIED.

Cochlea↗

PubMedDate not supplied

Short-range intermittent claudication and rest pain: microcirculatory effects of pentoxifylline in a randomized, controlled trial.

The efficacy of pentoxifylline (PXF) in severe intermittent claudication was studied comparing PXF and placebo. Patients were randomized into two treatment plans: PXF (2400 mg, four 600-mg tablets daily) or equivalent placebo was administered for 10 days. The exercise protocol associated with treatment was conducted under supervision. Skin flux (RF) was measured at rest and after 1 minute of exercise (AEF = after exercise flux; 3 km/hr, 12% inclination) with laser Doppler. PO2 and PCO2 were measured at the dorsum of the foot. All 20 included patients completed the study. The two groups were comparable. In the PXF group there was a significant increase in RF, AEF, and in PO2 (p<0.05); PCO2 was decreased (p<0.05). There were also changes in the placebo group, significantly lower than those observed in the PXF group (p<0.05). In conclusion high-dose PXF treatments improved all microcirculatory parameters in subjects with short-range claudication even with a short period of treatment.

Aged↗