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Peripheral arterial disease (PAD) is associated with cerebral and coronary artery disease. Symptomatic PAD affects about 5% of people over 55 years; many more have asymptomatic PAD. Early detection enables modification of arterial disease risk factors. Diagnostically, assessment of symptoms or signs can be unreliable; ankle brachial pressure index (ABPI) testing is time-consuming and few healthcare professionals are properly trained. This study assessed the diagnostic accuracy of multi-site photoplethysmography (MPPG), an alternative non-invasive test for PAD, in primary care. PAD patients identified from general practice registers were age- and sex-matched with controls. Participants were assessed using MPPG, ABPI and duplex ultrasound (DUS). Outcome measures were sensitivity and specificity of MPPG and ABPI (relative to DUS) and concordance. MPPG test results were available in 249 of 298 eligible participants from 16 practices between May 2015 and November 2016. DUS detected PAD in 101/249 (40.6%). MPPG sensitivity was 79.8% (95% confidence interval [CI] 69.9–87.6%), with specificity 71.9% (95% CI 63.7–79.2%). ABPI sensitivity was 80.2% (95% CI 70.8–87.6%), with specificity 88.6% (95% CI 82–93.5%). With comparable sensitivity to ABPI, MPPG is quick, automated and simpler to do than ABPI; it offers the potential for rapid and accessible PAD assessments in primary care. [ABSTRACT FROM AUTHOR]

An objective hemodynamic assessment is mandatory to confirm Critical Limb Ischemia (CLI). Toe pressure measurement is recommended. We compared toe measurements obtained using the Laser Doppler method (LD) (PERIMED PeriFlux, Sweden) considered as the reference test, with those obtained with a portable device using photoplethysmography (PPG) (Sys Toe Atys Medical, France). A total of 93 (123 legs) patients from 3 French hospitals with a clinical suspicion of CLI were included and had measurements with each device carried out by skilled operators. PPG was unable to provide a measurement in 10 patients. Lin's Coefficient correlation concordance (CCC) and Bland and Altman's scatter plot were analyzed for the 83 remaining patients, CCC was.84 95%CI (.77–.89). For detection of CLI, Cohen's kappa was.67 95%CI (.53–.81). The PPG device is fairly reliable for toe pressure measurement in patients suspected of CLI and could be useful when LD is not available. However, it fails to deliver a measurement in approximately 10% of cases. No conclusion should be made about CLI for these patients when no measurement is obtainable and other methods should be used (LD, transcutaneous oxygen pressure) to assess perfusion of the limbs. [ABSTRACT FROM AUTHOR]

We assessed the utility of a 3-grade classification of photoplethysmography (PPG) with cold water provocation test in Raynaud phenomenon (RP). A total of 35 patients with RP and 38 healthy volunteers were recruited. In healthy volunteers, PPG was measured twice at intervals of 30 minutes for evaluating reproducibility of test. Percentage variation of the PPG amplitude in post- versus precold provocation was expressed on a 3-grade scale at 1, 3, and 5 minutes (reflection index: RI) in patients with RP. The improvement pattern of the PPG (IPPPG) was evaluated by summing the score differences from RI1 min to RI3 min and RI5 min. After a therapeutic period of 8 weeks with nifedipine, the decreases in posttherapeutic RI3 min and RI5 min were statistically significant (P < .05). Subgroup analysis of IPPPG showed statistical significance in patients with negative fluorescent antinuclear antibody (P < .05). The analysis of cold-provoked PPG waves demonstrated and quantified improvements in peripheral arterial circulation in RP. [ABSTRACT FROM AUTHOR]

Purpose: We evaluated the sensitivity and specificity of ankle–brachial index (ABI), photoplethysmography (PPG), and continuous-wave Doppler ultrasound (CWD) in the detection of anatomically stenotic peripheral arterial disease (PAD). Methods: Ninety-seven patients (194 legs) patients who had coincidentally undergone computed tomography angiography (CTA), ABI, PPG, and CWD for the evaluation of PAD were retrospectively reviewed. Sensitivity and specificity were measured. Results: Among 194 legs, 163 (84%) legs had stenotic PAD on CTA. Overall sensitivity of ABI, PPG, and CWD was 69.3%, 81.6%, and 90.8% and specificity was 96.8%, 77.4%, and 64.5%, respectively. Ankle–brachial index showed a statistically significantly decreased sensitivity (14.8%) for below trifurcation level stenosis compared with CWD (92%) and PPG (67%). The sensitivity of ABI was also significantly decreased in single level and moderate stenosis (45.1% and 42.1%, respectively). In contrast, the sensitivity of CWD and PPG was not significantly decreased. Conclusion: The ABI showed significantly decreased sensitivity especially in stenosis below the trifurcation level. Both PPG and CWD were complementary to ABI in these groups of patients. [ABSTRACT FROM PUBLISHER]

Smoking is associated with increased arterial stiffness. However, the impact of smoking cessation on arterial stiffness remains unknown. We investigated the effect of smoking cessation on arterial stiffness. Healthy participants (n = 209) were divided into nonsmoking (NSm, n = 96), quit smoking (QSm, n = 61), and maintained smoking groups (MSm, n = 52). Arterial stiffness indexes (ankle–brachial index [ABI] and brachial–ankle pulse wave velocity [baPWV]) were assessed at baseline, and after 6 and 12 months. Baseline, arterial stiffness was significantly higher in the MSm and QSm groups than in the NSm group (P < .001). In the QSm group, there was significant difference in ABI between baseline and 12 months (P = .03). No significant differences were shown in baPWV. Both ABI and baPWV were similar between QSm and MSm group at 12 months. However, there was significant difference between QSm and NSm groups (P < .001). This study shows that 12 months of smoking cessation is associated with improved arterial stiffness. [ABSTRACT FROM PUBLISHER]

The article discusses the ankle–brachial pressure index (ABPI) method which is useful in detecting peripheral arterial disease (PAD). The systolic blood pressure (SBP) of the posterior tibial and dorsalis pedis arteries of each leg with the higher brachial pressure of either arm are compared to measure ABPI. Patients with arterial calcification and incompressible arteries ABPI is less effective. It is also discussed that measurement of ABPI should be improved.

Cardio-ankle vascular index (CAVI) using the volume plethysmographic method is a noninvasive atherosclerotic indicator which is not influenced by blood pressure. Coronary intravascular ultrasound (IVUS) is a reliable technique to measure progression of atherosclerosis. The association between CAVI and IVUS has not been reported. The aim of this study was to evaluate the association between CAVI and the plaque burden measured by IVUS in the left main coronary artery (LMCA) in patients with coronary heart disease and normal LMCA. Cardio-ankle vascular index was significantly correlated with percentage plaque area (r = .649, P < .0001) measured by IVUS in the most diseased segment of LMCA. Cardio-ankle vascular index remained significant among cardiovascular disease risk factors included in the multiple regression analysis predicting percentage plaque area. Cardio-ankle vascular index was a good atherosclerotic indicator and associated with the plaque burden in nonculprit and angiographically normal LMCA. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess the relationship between ankle brachial pressure index and pulse wave velocity in patients with peripheral arterial disease. Methods: Brachial-knee and brachial-ankle pulse wave velocity were measured by pneumoplethysmography using cuffs in a standard technique. Correlation between pulse wave velocity and Doppler-ankle brachial pressure index was assessed by Spearman correlation and receiver operating curves. Results: A total of 133 claudicants were assessed. Analysis by developing receiver operating curves for ankle brachial pressure index and pulse wave velocity showed that patients with ankle brachial pressure index over 0.6 were more likely to have a bk-pulse wave velocity over 9.2 m/s and ba-pulse wave velocity over 9.5 m/s. Conclusion: These results show for the first time that nondiabetic vascular patients may have measurable significant arterial stiffness independent of an impaired ankle brachial pressure index. These data suggest that pulse wave velocity may be valuable in screening and evaluating the severity of peripheral arterial disease. [ABSTRACT FROM AUTHOR]

Sympathetic responses to provocative tests have shown to provide an early prognosis of abnormalities in the human autonomic nervous system. Photoplethysmographic signal characteristics have been studied to identify vascular diseases. However, knowledge about the pulse-added arterial volume of the photoplethysmographic waveforms during these clinical investigations is limited. In all, 16 normotensive adults (9 men) were recruited to perform 3 provocative test (2 postural changes and 1 resistive breathing) activities with photoplethysmographic signals being monitored on the upper and lower peripheries using customized devices. In all, 4 parameters derived from the photoplethysmographic waveforms that related to the pulsatile tissue blood volume changes were then assessed. The results obtained showed that amplitude-related parameters during these activities showed significant changes (>9.63%; P < .05). However, comparison of pulse-added arterial volume showed insignificant changes (<5.56%; P > .05) for all test settings. Hence, the findings herein suggest that there is clinical potential in using this aspect of the photoplethysmographic waveform. [ABSTRACT FROM AUTHOR]

Peripheral arterial disease may lead to lower limb claudication and increased risk of systemic vascular dysfunction. In this article, the authors have investigated the peripheral vascular dysfunction evaluating forearm blood flow using venous occlusion plethysmography, lipid profile, and C-reactive protein in 60 patients with moderate intermittent claudication treated during 20 weeks with placebo (n = 16), cilostazol (200 mg/d; n = 17), or pentoxifylline (1200 mg/d; n = 15) in a randomized double-blinded clinical trial, taking into account smoking. Forearm blood flow after reactive hyperemia response (FBFh) or oral nitroglycerine spray to evaluate endothelial-dependent and endothelial-independent vasodilation, respectively, pain-free and maximal walking distance, levels of C-reactive protein, triglycerides, cholesterol, low-density lipoprotein, and high-density lipoprotein-cholesterol in plasma were determined. The results showed that there was an improvement in the high-density lipoprotein-cholesterol, pain-free and maximal walking distance, and FBFh independent of treatment in nonsmoking patients. Cilostazol increased high-density lipoprotein-cholesterol level, maximal walking distance, and FBFh, whereas pentoxifylline reduced C-reactive protein level and increased maximal walking distance in total and nonsmoking groups. No treatment was effective in smokers. [ABSTRACT FROM AUTHOR]

6A new optical device based on the photoplethysmograph (PPG) method and an innovative algorithm for the assessment of lower-extremity peripheral arterial disease was investigated prospectively in patients with type II diabetes. This new functional PPG (fPPG) technique uses a cuffless functional test to assess diabetic peripheral arterial disease without operator dependency and the incompressible arteries, issues associated with ankle brachial pressure index (ABPI) measurement. Diabetic patients (n = 24; 47 legs; age, 70 ± 3 years) were recruited from the vascular clinic, and controls (n = 15; 30 legs; age, 66 ± 5 years) were recruited from the orthopedic outpatient clinic. All underwent resting ABPI, fPPG, and duplex angiography (DA) as ‘gold standard.— fPPG requires the placement of an optical probe on the toe for acquisition of pulsatile arterial perfusion for a period of 30 seconds with the leg in supine and raised at 45° positions. The data were analyzed, and indices were generated by an automated computer system. In those with diabetes, fPPG correlated significantly with DA (r = -.68, P < .01) and ABPI (r = -.65, P < .01). We also found a significant correlation between ABPI and DA (r = .81, P < .01). The analysis of the receiver operator curve showed that optimum sensitivity and specificity for ABPI and fPPG were 80% and 93% and 83% and 71%, respectively, against DA. This method uses changes in pulsatile arterial blood volume using a simple cuffless functional test. The fPPG investigation period was much shorter (5 minutes) with independence of operator skills, whereas ABPI took longer (10-15 minutes) and required operator experience. Although the fPPG results are promising, further improvement (eg, by incorporation of functional skin color and temperature changes) is required to improve the sensitivity and specificity of the system. [ABSTRACT FROM AUTHOR]

It is common belief that the use of high-heeled shoes is deleterious to venous return, by impairing the efficiency of the muscular calf pump. Ambulatory venous pressure obtained with dorsal foot venipuncture is the gold standard in the evaluation of venous pressure during walking, but it is not routinely used in clinical practice. The objective of the present study was to determine the variations in leg venous pressure obtained with a new noninvasive method, in individuals without venous disease, walking without shoes and wearing high-heeled shoes. A new method of evaluation of the venous pressure by means of air plethysmography was applied to 10 volunteers (20 limbs). The patients were evaluated while standing, with orthostatic flexion and extension foot movements, and while walking on a treadmill barefooted and wearing high-heeled shoes. It was found that the variation on the cuff pressure during walking with high-heeled shoes was higher than the variation on the cuff pressure walking barefooted (52.2 ±8.89 × 26.65 ±6.7 mm Hg, p<0.0001), and the final hydrostatic venous pressure was lower (51.5 ± 12.78 × 61.5 ±8.44mm Hg). The use of high-heeled shoes increases muscular effort during walking and diminishes the leg venous pressure compared with barefooted. [ABSTRACT FROM AUTHOR]

Evaluates the effects of total triterpenic fraction of Castella asiatica on capillary filtration rate (CRF) in patients with venous hypertension. Assessment of CPR by venous occlusion plethysmography; Correlation between CRF reduction and the improvement of ankle and foot edema; Control and reduction of signs and symptoms of venous hypertension.

Presents methods of evaluation and quantification of microangiopathy in high perfusion microangiopathy, chronic venous insufficiency and diabetic microangiopathy. Microcirculatory methods; Laser Doppler flowmetry; Strain-gauge plethysmography; Venous occlusion plethysmography.

Investigates the effect of coexistent type 2 diabetes and arterial hypertension on endothelial dysfunction in resistance of human forearm vasculature. Measurement of forearm blood flow using venous occlusion plethysmography; Comparison of endothelium-independent and -dependent flow response; Indications of progressive endothelial dysfunction.

To define the role of air plethysmography (APG) in the clinical diagnosis and quantitative assessment of chronic venous insufficiency (CVI), APG studies were performed on 582 limbs in 291 patients with signs and symptoms of CVI. One hundred and thirty-one limbs were classified into group I (no evidence of CVI), 291 into group II (mild CVI), and 160 into group III (advanced CVI). On APG, the mean venous filling index (VFI) was 1.45 mL/s, 3.90 mL/s, and 5.25 mL/s in groups I, II, and III respectively (p < 0.05). The mean ejection fraction (EF) and mean residual volume fraction (RVF) also showed significant differences between the limbs with CVI and the contralateral normal limbs, but the values were similar for the different severities of CVI limbs. The amount of overlap in VFI, EF, and RVF values among the clinical groups was considerable. Discrimination analysis derived a VFI value of 2.67 mL/s as a cutoff point between normal limbs and limbs with CVI, with a positive predictive value of 96%. In conclusion, APG is a simple and noninvasive test for quantitative assessment of the different components of CVI, valvular reflux, and calf muscle pump function. However, only VFI correlated significantly with the severity of CVI. VFI, with its high positive predictive value, may be useful in diagnosis of CVI, and it may serve as an objective quantitative measurement for monitoring the effect of treatment. [ABSTRACT FROM AUTHOR]

The ankle-brachial systolic pressure index (ABI), a noninvasive measure of peripheral arterial occlusive disease (PAOD) severity, is considered a marker of atherosclerosis and an independent predictor of mortality. However, it is not known whether factors other than PAOD severity, such as cigarette smoking, have an effect on ABI measurement. Therefore, the authors examined the acute effects of cigarette smoking on ABI and the peripheral circulation in 10 older (63 ±10 years) chronic smokers (39 ±37 pack-years) with PAOD (ABI = 0.64 ±0.14). The patients were instructed to refrain from smoking and from consuming caffeine-containing beverages for at least 12 hours before the tests. The patients were randomly assigned to 2 days of testing consisting of a nonsmoking and a smoking day. Resting heart rate, blood pressure, ABI, and calf blood flow by plethysmography were obtained on both testing days. The smoking day consisted of smoking two filter cigarettes over a period of 10 minutes before the measurement of ABI and calf blood flow. The ABI on the smoking day (0.55 ±0.11) was lower (p=0.008) than on the nonsmoking day (0.64 ±0.14) owing to a lower (p=0.020) ankle systolic blood pressure (81 ±28 vs 93 ±28 mmHg). Brachial systolic blood pressures, heart rate, and calf blood flow were not altered by smoking (p>0.05). These results demonstrate that the acute effect of cigarette smoking lowers the ABI in chronic smokers with intermittent claudication, thereby yielding evidence of a transient deleterious effect of cigarette smoking on the peripheral circulation in chronic smokers. [ABSTRACT FROM AUTHOR]

The authors encountered a forty-nine-year-old man with a lower limb ulcer refractory to intensive conservative therapy. No varicose vein was found anywhere, and the usual phlebographies and foot venous pressure measurement failed to diagnose it as a venous stasis ulcer. A direct phlebography method developed by the authors, in which a thin catheter is inserted into the deep vein, disclosed a reflux of the popliteal vein or a deep muscle branch from which an incompetent perforator arose toward the superficial vein above the ulcer. Air plethysmography (APG) showed a severe impairment of the calf muscle pump function, lie underwent a subfascial ligation of two incompetent perforators together with a stripping of the great saphenous vein passing under the ulcer. Postoperatively, this ulcer was cured in an early phase, and the calf muscle pump function showed improvement in the APG. [ABSTRACT FROM AUTHOR]

In an attempt to examine the role of the thermoregulatory apparatus in the etiology of Raynaud's phenomenon (RP), the authors exposed 15 women with RP and 12 controls to central body cooling and central body warming. Subjects were placed in an environmental chamber at 25°C. Their right hand was placed in an annex of the chamber, which was insulated from the main chamber and maintained at a constant temperature of 25°C throughout the experiment. Blood flow was measured in the digits of the right hand by venous occlusion strain gauge plethysmography and skin thermometry. Body temperature was measured with an oral thermometer. The temperature of the chamber was then increased to 35°C and then reduced to 13°C for twenty-five minutes with measurements repeated. Following this period patients were rewarmed in an ambient temperature of 35°C for twenty minutes. Results: subjects with RP had significantly lower blood flow at all stages of the test; moreover, their digital rewarming response following central cooling was considerably prolonged when compared with controls. Body temperature was lower and dropped significantly more in the RP group following the cold challenge. The authors conclude that subjects with RP have an impaired thermoregulatory mechanism. This may partially explain cold sensitivity. [ABSTRACT FROM AUTHOR]

Although great advances have been made in the operative treatment of vascular disorders, the management of most venous problems is still nonsurgical, Daflon 500 mg is a micronized flavonoid mixture of 90% diosmin and 10% hesperidin that has phlebotonic properties. The efficacy of Daflon 500 mg has been investigated in three double-blind, randomized trials using strain gauge plethysmography to provide quantitative information on venous hemodynamics in patients with chronic venous insufficiency. In total, 183 patients were treated with Daflon 500 mg versus a control group of equal number of patients, Daflon 500 mg produced a significant decrease in venous capacitance, venous distensibility, and venous emptying time (PΛ0,001), In addition, these changes were accompanied by improvement in clinical symptoms and a decrease in the supramalleolar circumference. Clinical side effects were rare and led to treatment withdrawal in only 3 patients. It is concluded that Daflon 500 mg is of benefit to patients with chronic venous insufficiency. [ABSTRACT FROM AUTHOR]

Over recent years, a number of functional investigations have been developed that allow a better evaluation of the physiology of the cutaneous microcirculation than that provided by the morphologic method. These investigations are also useful in pharmacologic studies. Following a review of the anatomy and physiology of the cutaneous microcirculation, the author presents the principal techniques of investigation and the results obtained with Daflon 500 mg on the cutaneous microcirculation evaluated by photoplethysmography of the skin in patients with venous insufficiency and leg ulcers. [ABSTRACT FROM AUTHOR]

A randomized, double-blind, multicenter trial was performed to study the pharmacodynamics and clinical activities of Daflon 500 mg, in comparison with a nonmicronized diosmin. Daflon 500 mg is a micronized purified flavonoidic fraction consisting of 450 mg of diosmin and 50 mg of hesperidin per tablet, which has been micronized in order to ensure a better gastrointestinal absorption. Ninety patients with chronic venous insufficiency of the lower limbs, stabilized for one year, entered the study. They received either two tablets of Daflon 500 mg or an equivalent dose of nonmicronized diosmin in two divided doses each day during two months. The following parameters were studied: functional clinical symptoms in the lower extremities, ankle circumference measurement, strain gauge plethysmographic parameters with 20, 40, and 60 mmHg venous occlusion, and clinical and biochemical acceptability. Statistically significant changes were obtained in both groups of patients in comparison with baseline values. However, the improvements in all clinical symptoms and plethysmographic parameters (maximum increase of venous volume at 60 mmHg and total time for emptying) were significantly better with Daflon 500 mg than with nonmicronized diosmin. The clinical and laboratory acceptability was similar in both groups. However, the percentage of satisfied patients was 95% in the Daflon 500 mg group, versus 80% in the nonmicronized diosmin group (p < 0.01). In conclusion, the pharmacodynamic and clinical activities of Daflon 500 mg are superior to those of an equivalent dose of nonmicronized diosmin and demonstrate the therapeutic advantage of a micronized formulation in the treatment of chronic venous insufficiency. [ABSTRACT FROM AUTHOR]

Chronic venous insufficiency (CVI) is a challenge to the medical profession, for clinical examination provides useful information on CVI, but it is qualitative and does not suffice, especially in patients with isolated deep venous insufficiency but without conspicuous signs of CVI. Ambulatory venous pressure (AVP) measurement has diagnostic value and prognostic capabilities, but it is invasive, is not suitable for repeated use in the same patient, and is not suitable as a screening test. The author surveys noninvasive, volumetric methods that correlate to AVP and that have been developed as alternatives. These include foot volumetry, photoplethysmography, light reflection rheography, ambulatory strain gauge plethysmography, and air plethysmography. The author discusses each with respect to technique, site of measurement, type of exercise used, parameters, correlation to AVP, clinical application, and predictive value. He also describes the tests' ability to determine presence or absence of disease, type of disease, and quantification of disease. [ABSTRACT FROM AUTHOR]

Recently, the sensitivity of impedance plethysmography (IPG) for the diagnosis of acute deep-vein thrombosis (DVT) in symptomatic outpatients has been questioned. In order to verify whether a change in the venographic pattern of DVT has occurred over years, accounting for the decreased sensitivity of IPG, the authors compared two series of consecutive venograms demonstrating proximal DVT, performed between 1984–1988 (166 patients) and 1990–1992 (140 patients). They evaluated both the extension and the occlusiveness of deep-vein thrombi in the two series. Moreover, changes in the referral characteristics of patients were investigated. In the second series of venograms a significant decrease in thrombi extension, expressed by a lower prevalence of iliac vein thrombosis (29% versus 43%; P = 0.0074) was observed; moreover, a significant increase in the prevalence of nonocclusive thrombi (22% versus 8%; P = 0.0004) was also recorded in the second series when compared with the first. During the study period, among the referral characteristics of patients, the authors observed both a significant decrease in the prevalence of proximal DVT (from 31% to 24%; P < 0.01) and a slight and not statistically significant decrease in the median time elapsed between onset of symptoms and referral for objective testing (from eight and a half to seven days). In conclusion, proximal deep-vein thrombi are currently less extensive and occlusive than observed in the past. These results might depend on earlier referral of less symptomatic patients and might explain the recently reported decrease in IPG sensitivity for proximal DVT. [ABSTRACT FROM AUTHOR]

Capillary filtration (CF) was assessed in 43 patients with venous hypertension and in 10 normal subjects by means of strain gauge plethysmography. The patients were then divided into two treatment groups; 22 were treated with Daflon, 500 mg tid, and 21 with Daflon, 500 mg bid. The normal subjects were also treated (500 mg tid). After four weeks CF was significantly decreased in all subjects, the decrease being higher in the high-dose groups. CF did not significantly change in normal subjects. In conclusion Daflon decreases CF in subjects with venous hypertension and the CF decrease is dose related. [ABSTRACT FROM AUTHOR]

Certain types of occupation-related vibrations can cause traumatic vasospastic disorders. Findings from clinical examination are often normal at the office consultation. Measurements of finger blood flow using plethysmography while the local ambient temperature is changed can give important information about the severity of traumatic vasospastic disorder and the concomitant disability. This technique can also be used for follow-up of the finger blood flow after withdrawal from vibrations. [ABSTRACT FROM AUTHOR]

The effects of cooling of a hand on lateral and contralateral digital skin blood flow were investigated in 18 patients with primary or secondary Raynaud's phenomenon. The aim of the study was to compare photoelectrical plethsmography (PhEP) and laser Doppler flowmetry (LDF). PhEP and LDF were used simultaneously for skin blood flow measurements of the third linger of both hands. One hand was cooled in water from 33° to 3° C in steps of 3° C, each step lasting four minutes. It was followed by a recovery period of ten minutes in room air of 24° C During stepwise cooling from 33° to 9°C the relative PhEP and LDF values, measured on the cooled hand, decreased to 6.2°lo ± 32% and 10% ± 12% respectively. The correlation coefficients between LDF and PhEP varied between 0.79 and 0.99. In the contralateral hand the relative PhEP and LDF values decreased to 38% ± 30.°lo and 64% ± 7.9% respectively. The correlation coefficients between LDF and PhEP values were lower on the contralateral hand and ranged from 0.26 to 0.95. By calculating the LDF/PhEP ratios during cooling and recovery, more specific changes in red blood cell velocities during cooling were studied. Increasing LDF/PhEP ratios suggest increasing red blood cell velocities during cooling at 9° C and a difference in the measuring methods. For testing the severity of Raynaud's phenomenon and the effect of treatment the results of both methods show consistent and quite comparable results when measured on the cooled hand. The effect of indirect cooling on the contralateral hand is, however, less consistent. [ABSTRACT FROM AUTHOR]

By use of noninvasive tests (Doppler segmental pressure study, supraorbital Doppler flow analysis, and segmental plethysmography), coexistent carotid (CTD) or lower extremity peripheral vascular disease (PYD) were diagnosed and correlated with subjective symptoms, coronary risk factors (CRFs), coronary arteriograms (CAGs), cardiac hemodynamics. and infarct size in 121 consecutive patients with documented coronary artery disease (CAD). PYD was found in 16.5%, CTD in 33.1%, and both PVD and CTD in 9.9% of the patients studied; 20% of PVD patients and 47.5% of CTD patients were asymptomatic with respect to coexistent PVD or CTD. There were no significant differences between the presence or absence of PVD or CTD as regards number of CRFs, Killip classification, cardiac hemodynamics, or number of stenotic coronary arteries. However, serum creatine kinase (CK) and CKMB release curves in the PYD group showed significantly higher peak CK and peak CKMB values than those in the PVD(-) group (4096 ± 5408/282 ± 263 vs 1706 ± 1715/179 ± 186, p <0.05) because of the higher prevalence (100%) of multivessel disease on CAG. Investigation of the relationship of CRFs to coexistent PYD revealed that the smoking ratio in men (86.7%) and the hypertension ratio in women (80%) were extremely high in PVD patients, and statistically significant differences between PVD( +) patients and PVD( -) groups were found with respect to the obesity ratio (p <0.05) in men and the hyper-cholesterolemia ratio (p < 0.05) and obesity ratio (60%, p <0.05) in women. On the other hand, in CTD patients, the smoking ratio (84%) and hypertension ratio (64%) in men and the hypertension ratio (86.7%) in women were extremely high, and significant differences between CTD(+) patients and CTD( -) patients were found with respect to the smoking ratio (p < 0.05) and obesity ratio (p < 0.05) in men and the smoking ratio (p < 0.05) in women. For the entire group of patients, the ankle/brachial pressure index was significantly lower (p < 0.05) when CAD patients displayed four or more CRFs, suggesting the progression of PVD with increasing number of CRFs. The incidence and clinical features of coexistent PVD or CTD in Japanese CAD patients were documented in the present study. [ABSTRACT FROM AUTHOR]

The authors studied muscular blood flow (F), oxygen consumption rate (R), and oxygen extraction fraction (E) in 5 patients suffering from severe intermittent claudication (stage II). They applied the bolus technique of H2150 and 1502 with a detection by positron emission tomography (PET). Tomograms were recorded at the greatest diameter of the calfs, at rest and ten minutes after a treadmill walk test leading to the development of ischemic pain in the affected extremity. F and E data were compared with the values obtained by more usual methods, namely occlusive venous strain gauge plethysmography and femoral venous blood sampling. During the study, these patients received naftidrofuryl, a vasodilatator drug, in an intravenous dose of 600 mg diluted in 250 mL saline infused over a six-hour period in a placebo-controlled, double-blind, crossover protocol (two consecutive experiments, a week apart). The results showed that all blood flow values measured at rest and after exercise by PET were in close correlation (r = 0.71) with the plethysmographic findings. The agreement between the two methods of measuring blood flow was less obvious with an Altman's presentation of the data: there was a tendency to measure higher values with PET scan. Concerning E, the correlation was poor at rest. After exercise, the values were more elevated with PET and no correlation was found with blood samples. The authors found no significant effect of naftidrofuryl either on flow or metabolic data. [ABSTRACT FROM AUTHOR]

Matched groups of 7 to 8 patients with primary Raynaud's phenomenon, systemic sclerosis, and undifferentiated connective tissue disease and cold-tolerant normal control subjects were studied by simultaneous digital strain gauge plethysmography and laser Doppler capillary velocimetry during two controlled cycles of hand warming and cooling with and without addition of central cooling and during clinical maneuvers to evoke sympathetic tone. Transient vasoconstrictor responses of comparable degree could be evoked in all patient groups and in both the arterial and microvascular beds. While the addition of central cooling had little influence on arterial flow, patients with systemic sclerosis manifested a failure to maintain nutritive perfusion at finger temperatures associated with Raynaud's phenomenon. Linear regression and multivariate analysis suggested that finger temperature was the principal determinant of arterial flow in systemic sclerosis and that arterial flow was the principal determinant of microvascular perfusion. The inability of patients with systemic sclerosis to maintain nutritive flow in the face of either reflex or cold-induced proximal arterial constriction is consistent with their clinical propensity to ischemic tissue injury and separates these patients physiologically from other forms of Raynaud's phenomenon. [ABSTRACT FROM AUTHOR]

The aim of our study was to evaluate the sensitivity, the specificity, and the positive and negative predictive values of a recently developed computerized impedance plethysmography (CIP) in the diagnosis of deep vein thrombosis (DVT); 117 consecutive outpatients with a clinical suspicion of DVT were evaluated. After informed consent was obtained, a CIP and, within twenty-four hours, a venography of the symptomatic lower limb were performed in each patient. The results of CIP were compared with the results of contrast venography, which was considered as the gold standard. As far as the diagnosis of both proximal and distal DVT was concerned, the accuracy of CIP was 88.5%; the sensitivity and specificity were 95.1% and 83.6%, respectively; the positive and negative predictive values were 81.2% and 95.8%, respectively. When the diagnosis of only proximal deep vein thrombosis was considered, the accuracy of CIP was 88.8%; the sensitivity and specificity were 97.1% and 83.6%, respectively; the positive and negative predictive values were 79.0% and 97.8%, respectively. The authors conclude that the newly developed CIP has a diagnostic accuracy similar to that of traditional impedance plethysmography. Moreover, being completely automated and portable, CIP can play an important role in the bed- side diagnosis of DVT. [ABSTRACT FROM AUTHOR]

The present work was performed to test the sensitivity of transcutaneous oximetry in evaluating the first stage of peripheral artery disease in patients with few symptoms. Eighteen nondiabetic patients, stage II according to Fontaine and classified according to their walking capability and Doppler examination, were investigated. Ten healthy subjects served as controls. Measurements were performed with the subjects standing and during exercise on a treadmill. Postischemic hyperemia was also evaluated with strainguage plethysmography. Standing values did not discriminate between patients and controls; on the contrary the pattern of the early phase of trancutaneous oximetry curves obtained during exercise allowed the investigators to distinguish the symptomatic patients with minimal symptoms. Accuracy and sensitivity of the method further increased when regional perfusion index was considered. [ABSTRACT FROM AUTHOR]

Because the literature comparing the effects of vasodilators on forearm and calf vessels is very scarce, the authors compared different vasodilators used in cardiovascular medicine in a group of volunteers. The peripheral effects were measured in the sitting position by plethysmography at the calf and at the forearm. At the forearm, comparable dilator effects were seen in arteries and veins. At the calf there was a trend for arterial flow to decrease as venous capacitance increased. Vascular response seen in one limb was not representative of the whole circulation. The changes observed were dependent not only on the vascular area investigated but also on the dose used. [ABSTRACT FROM AUTHOR]

Sixty patients with varicose veins, in the age range 25 to 52 years, entered the trial and were divided by random allocation into 2 equal groups. The first group received calcium dobesilate orally in dosage of 750 mg daily while the second remained untreated. Out of 25 patients who completed the 3-month treatment course, clinical improvement occurred in 19 (76%). Mercury strain gauge plethysmography in those 19 patients showed a statistically significant mean fall in the venous distensibility index, in maximum venous outflow and in the capillary filtration coefficient after the course of calcium dobesilate. The mean erythrocyte sedimentation rate in the 25 patients fell from 40 mm in 1 hour (Westergren) before treatment to 10 mm at the end of the course. In 42% of the patients there was a fall in serum globulin concentration and correction of the albumin/globulin ratio and in 35% there was a slight fall in serum fibrinogen concentration. Possibly calcium dobesilate's known action in lowering blood viscosity contributes to its beneficial effect in varicose veins. [ABSTRACT FROM AUTHOR]

Pentoxifylline is the prototype of a new class of drugs that improve peripheral blood flow mainly by increasing red blood cell flexibility. Few studies have been performed to objectively evaluate the effect of the drug in a routine clinical setting. In 11 patients with intermittent claudication, photoplethysmography was used to monitor the effect of pentoxifylline on the microcirculation in the lower extremities. Values obtained improved significantly (p < .0001) under therapy. Concomitant measurements of ankle-brachial indices showed no significant changes despite clinical improvement. Diabetic patients in this study seemed to benefit from treatment with pentoxifylline at least as much as nondiabetic patients. Photoplethysmography proved to be a very effecient and inexpensive method of studying the effects of pentoxifylline. Ankle-brachial indices are not a suitable method of detecting flow changes attributable to the mechanism of action of this drug. [ABSTRACT FROM AUTHOR]

Accuracy in the diagnosis of lower extremity deep venous thrombosis (DVT) by physical examination and impedance plethysmography (IPG) is reviewed. Physical examination proved unreliable in distinguishing patients with and without acute disease. Swelling in the leg was, however, more prevalent in patients with DVT. The sensitivity and specificity of IPG were less than those reported by other groups. Venography remains the most reliable diagnostic procedure in our institution. [ABSTRACT FROM AUTHOR]

A short historical note on plethysmography is given and the development of the modern computerized pneumoplethysmograph is described. The computeraided pneumoplethysmogram (CAP), with proper programming, makes possible numerous computations that give new, useful, and rapid information about the patient. New applications of the CAP will quickly develop and the data collected will be quickly analyzed and displayed. [ABSTRACT FROM AUTHOR]

Ninety-four patients suffering from venous insufficiency of the lower limbs participated in a multicenter, double-blind versus placebo study. After randomization, they were allotted for a treatment period of two months to one of three groups: TECA 120 mg/day, TECA 60 mg/day, or placebo. A significant difference (p < 0.05) in favor of TECA was shown for the symptoms of heaviness in the lower limbs and edema, as well as for the overall evaluation by the patient. The venous distensibility measured by a mercury strain gauge plethysmograph at three occlusion pressures was improved for the TECA groups but aggravated for the placebo group. [ABSTRACT FROM AUTHOR]

The authors have developed a vascular reactivity test to cold using the digital plethvsmograph technique with a mercury strain gauge. Three types of arterial reactivity were determined: local reactivity after immersion of the hand in 11°C water, general reactivity after thorax ventilation, and cumulative reactivity associating both of these cooling modes. The method is based on tneasurement of the digital plethysmographic signal expressed as a ratio of a reference warm amplitude obtained after immersion of the hand in 45°C water for 3 mm. The method was tested and perfected in 66 control subjects before being applied to 65 patients with Raynaud's disease. Significant differences were noted between these 2 groups, especially in cumulative reactivity (p < 10-9), which led to numerical expression of results in 5 types of increasingly important reactivity. It would appear that the test has diagnostic and prognostic value in the exploration of vascular acrosyndromes and their therapeutic follow-up. [ABSTRACT FROM AUTHOR]

In sixteen patients with ischemic handsyndromes, strain gauge plethysmography was used as a noninvasive diagnostic test. Contrast-arteriography was available for comparison. These patients demonstrate the role for a noninvasive test in selecting patients with Raynaud's phenomenon or asphyxia for arteriography. [ABSTRACT FROM AUTHOR]

In order to find the correlations existing between segmental and selective arterial blood flow volume, 20 healthy subjects have been submitted to calf venous occlusion plethysmography and Multichannel Digital Pulsed Doppler examination of the common femoral and popliteal arteries at rest. We found a linear correlation only between mean popliteal artery blood flow volume and plethysmographic calf blood flow volume (r=0,41; p < 0,01). We therefore suggest that venous occlusion plethysmography should not be used for the assessment of aorto-iliac and common femoral hemodynamics after direct arterial reconstructive surgery. Its use should be complementary to pulsed Doppler blood flow volume determination at the femoro-popliteal level, along with the usual pressure measurement. [ABSTRACT FROM AUTHOR]

With strain gauge plethysmography various procedures to assess the competence of the venous system in the lower leg were compared in 10 normal subjects. The reproducibility and ease of use were established, and normal values were obtained. It is concluded, that measurements in the sitting position are preferable to those in the standing perdition to measure the venous capacity, the dependency test is the method of choice. Rhythmic exercise to assess the effectiveness of the calf muscle pump can be restricted to five successive contractions. The refill time after exercise is not a suitable parameter to assess the competence of the venous valves. [ABSTRACT FROM AUTHOR]

The oculopneumoplethysmography has been a well established tool in the diagnosis of significant carotid artery stenosis; however, very few articles have studied the role of the OPG/Gee in detecting the postendarterectomy stenosis or thrombosis. The purpose of this article is to study that role. Eighty-two patients who had carotid endarterectomy and postoperative OPG/Gee were reviewed and compared with carotid arteriograms. Sixteen of these had bilateral and 66 had unilateral carotid endarterectomy. Seventy-nine of these patients had angiograms and three were explored. The total arteries studied were 98. Thirteen of these oculopneumoplethysmograms were done in the recovery room and the rest a few days to three years later. A carotid stenosis of 50% or more in diameter was considered significant. There were 10 positive oculopneumoplethysmograms, nine of which were confirmed by angiograms; i.e., 10.0% false positive rate. There were also three positive oculopneumoplethysmograms which were explored in surgery and found to be thrombosed; i.e., a total of 13 positive oculopneumoplethysmograms, 12 of which were confirmed which made the real false positive rate 7.7%. Eleven patients had positive arteriograms, nine of which had positive oculopneumoplethysmograms; i.e., 81.8% diagnostic sensitivity (9/11). Eighty-four arteries were considered normal by arteriogram (11 of which had insignificant stenosis), 83 of these had negative oculopneumoplethysmograms; i.e., 98.8% diagnostic specificity (83/84). The false negative rate was 2.4% (2/85). The overall accuracy rate was 96.8% (92/95). If the three explored arteries were added, the overall accuracy rate would be 96.9% (95/98). To conclude, the OPG/Gee is a valuable tool in detecting immediate postendarterectomy thrombosis or recurrent stenosis. The oculopneumoplethysmography has been well established as a tool in detecting significant carotid artery stenosis. However, very few articles studied the value of the oculopneumoplethysmography in detecting the postendarterectomy stenosis, whether immediate postoperative occlusion or recurrent carotid artery stenosis. The purpose of this paper is to study the value of the OPG/Gee in detecting the postoperative carotid stenosis or occlusion. [ABSTRACT FROM AUTHOR]

The unloading mechanisms and site of peripheral action of the new antianginal drug molsidomine was compared with isosorbide dinitrate (ISDN) in 14 patients with acute myocardial infarction using a Swan-Ganz catheter and venous occlusion plethysmography. Sublingual molsidornine (2-4 mg) increased calf venous capacitance (CVC) (0.42 ± 0.18 to 0.64 ± 0.09 ml/100 ml, p < 0.05) from 30 to 240 minutes, while simultaneously lowering of PCWP (25.9 ± 4.9 to 15.8 ± 7.3 mmHg, p < 0.05) and CVP (9.3 ± 3.7 to 5.8 ± 3.5 cmH2O, p < 0.05). Calf blood flow (CBF), calf vascular resistance (CVR), CI, TSPR and SWI were not affected significantly. Molsidomine reduced preload more than 240 minutes after its administration. Sublingual ISDN increased CBF into the initial IS minutes (1.19 ± 0.49 to 1.83 ± 0.98 mI/100mI/min, p < 0.05) and CVC from 5 to 60 minutes (0.42 ± 0.19 to 0.68 ± 0.24 ml/100ml p < 0.01) while simultaneously lowering PCWP (24.3 ± 2.2 to 14.6 ± 4.5 mmHg, p < 0.01) and CVP (9.0 ± 2.8 to 5.5 ± 3.5 cmH2O, p < 0.05). Neither drug affected cardiac index, blood pressure or systemic vascular resistance. These data suggest that molsidomine significantly lowered elevated preload (PCWP/CVP) by dilating venous capacitance vessels. Its length of action was 240 minutes compared with 60 minutes obtained with ISDN, which suggests this new agent may be of marked benefit in the AMI patients suffering from backward failure uncomplicated by forward failure in whom continued preload reduction is necessary. (Results are expressed as the mean ± standard deviation). [ABSTRACT FROM AUTHOR]

The clinical diagnosis of acute deep vein thrombosis (DVT) is but 50% accurate when compared to the results of contrast venography. This clinical inaccuracy had led to the dependence of the physician upon laboratory diagnosis. Whereas contrast venography is the gold standard of diagnosis, its expense, special equipment, personnel, and discomfort make it unsuitable for evaluating large numbers of patients. For this reason, numerous noninvasive tests utilizing plethysmographic and Doppler techniques have been developed to evaluate patients with suspected venous disease, and when expertly performed have a degree of accuracy of approximately 90%. This degree of accuracy coincides with the experience of our peripheral vascular laboratory using the Doppler venous examination. Based on these statistics, our current practice is to evaluate patients suspected of having DVT with a Doppler venous examination (Figure 1). If the test is abnormal or equivocal, contrast venography is usually obtained and anticoagulation recommended. Contrariwise, if the Doppler venous examination is normal, venography is not obtained, and anticoagulation treatment is not recommended. This practice should reduce the number of venograms in a patient population that is not at an increased risk of pulmonary embolism or repeated deep venous thrombosis. To evaluate the validity and safety of this practice, one hundred eighty-six patients with normal Doppler venous examinations in whom contrast venography was not obtained were evaluated and form the basis of this report. [ABSTRACT FROM AUTHOR]

The article presents information on the double-blind clinical and plethysmographic study of calcium dobesilate in patients with peripheral microvascular disorders. In Central Europe approximately 20% of the adult population above the age of thirty shows symptoms and signs of chronic venous insufficiency (CVI). The pathophysiology of CVI is directly related to the severe hemodynamic changes that gradually develop as the valvular system of the superficial and perforating veins becomes incompetent. The study confirms that calcium dobesilate significantly reduces the intensity of heaviness, pressure and edema in the lower extremities in patients with signs of venous valvular incompetency and venous hypertension. The remarkable subjective improvement reported by the patients correlates well with the correction of MVI, MVO and CF as determined with strain-gauge plethysmography.

The article cites a study on the flow of blood in the calf muscles during and after exercise. Furthermore, it sheds lights on measurements with Doppler ultrasound and venous occlusion plethysmography in healthy subjects and in patients with arterial occlusive disease. Exercise of the calf muscles is a more physiologic way to stress the circulation in the calf and can give more information about the functional reserve capacity. The ultrasonic Doppler velocimeter has a much better resolution in time but cannot determine volume flow. Volume flow is measured by venous occlusion plethysmography but this method can only be used when there are no movement artifacts.

Assessment of the hemodynamic effects of the IVC clipping by strain gauge plethysmography provides accurate quantitative data. These correlate very well with the other means of investigation used in the study. Eight patients were controlled in the Vascular Laboratory 9 to 43 months after clipping of the inferior vena cava. They submitted to clinical evaluation, Doppler ultrasound, isotopic venography, abdominal sonography, and strain gauge plethysmography of the lower extremities. This last method provided quantitative data; maximal venous outflow was found to be equivalent in the 8 patients included in the study and in a control group of 20 healthy young volunteers. Strain gauge plethysmography results correlate well with the other means of investigation and demonstrate the efficacy of the dilated venous collateral channels in restoring a normal venous return. [ABSTRACT FROM AUTHOR]

A radioisotope test using 131I-labelled serum albumin and venous occlusion plethysmography were performed simultaneously on the feet of normal individuals and patients with peripheral arterial disease during a period of reactive hyperemia. The radioisotope test includes a circulation time and a build-up curve reflecting a local clearance process which is characterized by the parameter M/2 -- delay. Between the parameter M/2 -- delay of the radioisotope test and the blood flow measured by the plethysmograph, the power relationship was found to be: M/2 -- delay = 74.01 F-0.74 with r = 0.69. The experimental data show that the plethysmographic blood flow measurement is an accurate method for the assessment of the peripheral circulation in normal individuals but is less suitable in patients with peripheral arterial disease. The radioisotope test appears to be more valuable than the plethysmographic blood flow measurement for the differentiation of normal individuals from patients with peripheral arterial disease and for the evaluation of the grade of ischemia. [ABSTRACT FROM AUTHOR]

A fixed procedure of strain gauge plethysmography in a control population aged between 20-30 years allows normal values for venous parameters (venous distensibility, emptying, and resistance) and capillary filtration coefficient, to be determined. High speed recording reveals two phases in venous emptying, one passive, purely elastic, and a second active phase, resulting from venous constriction. [ABSTRACT FROM AUTHOR]