Oscillometric measurement of the ankle-brachial index and the estimated carotid-femoral pulse wave velocity improves the sensitivity of an automated device in screening peripheral artery disease.

Background and aims: To overcome the time and personnel constraints of the Doppler method, automated, four-limb blood pressure monitors were recently developed. Their additional functions, such as measuring the estimated carotid-femoral pulse wave velocity (ecfPWV), have been, thus far, less studied. We aimed to compare the sensitivity and specificity of different ankle-brachial index (ABI), toe-brachial index (TBI), and ecfPWV measurement methodologies to evaluate their contribution to peripheral artery disease (PAD) screening. Methods: Among 230 patients (mean age 64 ± 14 years), ABI measurements were performed using a Doppler device and a manual sphygmomanometer. The Doppler ABI was calculated by taking the higher, while the modified Doppler ABI by taking the lower systolic blood pressure of the two ankle arteries as the numerator, and the higher systolic blood pressure of both brachial arteries as the denominator. The automated ABI measurement was carried out using an automatic BOSO ABI-system 100 PWV device, which also measured ecfPWV. TBI was obtained using a laser Doppler fluxmeter (Periflux 5000) and a photoplethysmographic device (SysToe). To assess atherosclerotic and definitive PAD lesions, vascular imaging techniques were used, including ultrasound in 160, digital subtraction angiography in 66, and CT angiography in four cases. Results: ROC analysis exhibited a sensitivity/specificity of 70.6%/98.1% for the Doppler ABI (area under the curve, AUC = 0.873), 84.0%/94.4% for the modified Doppler ABI (AUC = 0.923), and 61.5%/97.8% for the BOSO ABI (AUC = 0.882) at a cutoff of 0.9. Raising the cutoff to 1.0 increased the sensitivity of BOSO to 80.7%, with the specificity decreasing to 79.1%. The ecfPWV measurement (AUC = 0.896) demonstrated a 63.2%/100% sensitivity/specificity in predicting atherosclerotic lesions at a cutoff of 10 m/s. Combining BOSO ABI and ecfPWV measurements recognized 89.5% of all PAD limbs. Conclusion: The combined BOSO ABI and ecfPWV measurements may help select patients requiring further non-invasive diagnostic evaluation for PAD. The user-friendly feasibility may make it suitable for screening large populations.

Screening for Peripheral Artery Disease Using an Automated Four-Limb Blood Pressure Monitor Equipped with Toe-Brachial Index Measurement.

Toe-brachial index (TBI) measurement helps to detect peripheral artery disease (PAD) in patients with incompressible ankle arteries due to medial arterial calcification, which is most frequently associated with diabetes. We aimed to evaluate how an automated four-limb blood pressure monitor equipped with TBI measurement could contribute to PAD screening. In 117 patients (mean age 63.2 ± 12.8 years), ankle-brachial index (ABI) measurement was performed using the Doppler-method and the MESI mTablet. TBI was obtained via photoplethysmography (MESI mTablet, SysToe) and a laser Doppler fluxmeter (PeriFlux 5000). Lower limb PAD lesions were evaluated based on vascular imaging. A significant correlation was found between Doppler and MESI ankle-brachial index values (r = 0.672), which was stronger in non-diabetic (r = 0.744) than in diabetic (r = 0.562) patients. At an ABI cut-off of 0.9, Doppler (AUC = 0.888) showed a sensitivity/specificity of 67.1%/97.4%, MESI (AUC 0.891) exhibited a sensitivity/specificity of 57.0%/100%; at a cut-off of 1.0, MESI demonstrated a sensitivity/specificity of 74.7%/94.8%. The TBI values measured using the three devices did not differ significantly (p = 0.33). At a TBI cut-off of 0.7, MESI (AUC = 0.909) revealed a sensitivity/specificity of 92.1%/67.5%. Combining MESI ABI and TBI measurements recognised 92.4% of PAD limbs. Using an ABI cut-off level of 1.0 and sequential TBI measurement increases the sensitivity of the device in detecting PAD. The precise interpretation of the obtained results requires some expertise.

Examination of Lower Limb Microcirculation in Diabetic Patients with and without Intermittent Claudication.

Intermittent claudication is a frequent complaint in lower extremity artery disease, but approximately two thirds of patients are asymptomatic, most of which are diabetic patients. Non-invasive angiological and microrheological tests on diabetic subjects with and without intermittent claudication were performed in the present study. In total, 98 diabetic patients were included and divided into two groups: 20 patients (63.5 ± 8.8 years, 55% men, 45% women) had intermittent claudication, 78 patients (65.5 ± 9.3 years, 61.5% men, 38.5% women) were asymptomatic. Hand-held Doppler ultrasound examination, transcutaneous tissue partial oxygen pressure (tcpO2) measurement, Rydel-Seiffer tuning fork tests, and 6-min walk tests were performed, and erythrocyte aggregation was investigated. Ankle-brachial index (p < 0.02) and tcpO2, measured during provocation tests (p < 0.003) and the 6-min walk test (p < 0.0001), significantly deteriorated in the symptomatic group. A higher erythrocyte aggregation index and faster aggregate formation was observed in claudication patients (p < 0.02). Despite the statistically better results of the asymptomatic group, 13% of these patients had severe limb ischemia based on the results of tcpO2 measurement. Claudication can be associated with worse hemodynamic and hemorheological conditions in diabetic patients; however, severe ischemia can also develop in asymptomatic subjects. Non-invasive vascular tests can detect ischemia, which highlights the importance of early instrumental screening of the lower limbs.

Disease-Specific Quality of Life among Patients with Peripheral Artery Disease in Hungary.

Peripheral artery disease (PAD) is a progressive atherosclerotic disease significantly impacting functional status and health-related quality of life (HRQoL). This study aimed to investigate HRQoL among PAD patients in Hungary using the validated Hungarian version of the PADQoL questionnaire. Patients with symptomatic PAD were consecutively recruited from the Department of Angiology, Clinical Center, University of Pécs, Hungary. Demographics, risk factors, and comorbidities were registered. Disease severity was measured by Fontaine and WIFI stages. Descriptive statistical analysis, Chi-square test, and non-parametric tests were performed (p < 0.05). Overall, 129 patients (mean age 67.6 ± 11.9 years, men 51.9%) participated in our study. The Hungarian PADQoL demonstrated good internal consistency (α range: 0.745-0.910). Factors on intimate and social relationships gave the best (89.15 ± 20.91; 63.17 ± 26.05) and sexual function (28.64 ± 27.42), and limitations in physical functioning (24.68 ± 11.40) the worst scores. PAD had a significant negative impact on the social relationships of patients aged 21-54 years (51.6 ± 25.4). Fontaine stage IV patients experienced significantly lower HRQoL due to fear and uncertainty (46.3 ± 20.9) and limited physical functioning (33.2 ± 24.8). The Hungarian PADQoL identified central aspects of HRQoL. Advanced PAD was found to impact several areas of HRQoL, primarily physical functioning and psycho-social well-being, drawing attention to the importance of early diagnosis and management.

Hemorheological Parameters in Diabetic Patients: Role of Glucose Lowering Therapies.

Diabetes mellitus influences several important hemorheological parameters including blood viscosity, erythrocyte aggregation and deformability. In the present study, 159 type-2 diabetic patients and 25 healthy controls were involved. Patient's age, body weight, body mass index (BMI), smoking habits, physical activity, history of cardiovascular diseases, current antidiabetic therapy and concomitant medication were recorded. Patients were grouped according to their antidiabetic treatment with insulin, or with one or more of the following antidiabetic drugs: metformin, sulfonylureas, acarbose, or no antidiabetic therapy. Hemorheological measurements (hematocrit, erythrocyte aggregation, plasma fibrinogen, whole blood and plasma viscosity), von Willebrand factor activity, and platelet aggregation measurements were performed. Platelet aggregation was investigated with the method of Born. Plasma viscosity and red blood cell aggregation were significatly higher in diabetes. No significant difference was found in hemorheological parameters between different antidiabetic regimens. Whole blood and plasma viscosity and red blood cell aggregation correlated with glucose levels but not with HbA1C levels. In conclusion, plasma and whole blood viscosity, as well as red blood cell aggregation appear to be associated with concurrent hyperglycemia, but not with the quality of glycemic control or the applied antidiabetic treatment. Platelet aggregation induced by ADP or epinephrine does not seem to be associated with diabetes even at subthreshold doses.

Hungarian adaptation of the Peripheral Artery Disease Quality of Life questionnaire / A perifériás veroérbetegek életminoségét vizsgáló angol nyelvu kérdoív magyar adaptálása.

Összefoglaló. Bevezetés: A perifériás veroérbetegség napjaink egyik világméretu népegészségügyi problémája, több mint 200 millió embert érint világszerte. A Peripheral Artery Disease Quality of Life (PADQOL) kérdoívet azzal a céllal fejlesztették ki, hogy a betegség fizikai tünetein kívül annak szubjektív betegségterhét, pszichoszociális és emocionális hatásait is vizsgálja. Célkituzés: Az eredeti, angol nyelvu PADQOL betegségspecifikus, önkitöltos kérdoív magyar nyelvu, érvényes változatának kifejlesztése, annak fordítása, kultúrközi adaptációja és magyar nyelvi validálása. Módszerek: Az életminoség-kérdoív lingvisztikai validálása nemzetközi protokoll alapján történt: két szakfordító külön-külön lefordította a kérdoívet angol forrásnyelvrol magyarra; egy harmadik szakfordító bevonásával elkészült a két verzió szintézise, majd azt két, angol anyanyelvu fordító visszafordította angol forrásnyelvre, amit konszenzusmegbeszélés követett. A "pre-final" magyar verzió érthetoségét 30, angiológiai járó és fekvo beteg bevonásával, kognitív interjúk lefolytatásával, pilotvizsgálat során teszteltük. A PADQOL kérdoív faktorstruktúrájának feltárásához faktoranalízist végeztünk, az alskálák megbízhatóságát, a tételek belso konzisztenciáját a Cronbach-alfa-együttható kiszámításával vizsgáltuk. Az elemzésekhez IBM SPSS 23.0 programcsomagot használtunk. Eredmények: A PADQOL nyelvi validálása jelentéstani, tapasztalati és idiomatikus ekvivalencia tekintetében nem jelentett nehézséget. A kognitív interjúk során egy kérdés esetén tapasztaltunk értelmezési nehézséget. A kérdoív "pre-final" verziója tartalmilag és nyelvileg könnyen értheto, kitöltése nem okoz nehézséget. Az egyes dimenziók Cronbach-α-értéke 0,624 és 0,887 között volt. A legrosszabb értéket a Félelem és bizonytalanság (score-átlag: 14,07) életminoség-dimenzió mutatta. Következtetés: Létrehoztuk a PADQOL kérdoív végso magyar verzióját, mely méroeszköz alkalmas a nyelvi és kultúrközi adaptáció következo lépésének elvégzésére, nagyobb betegpopuláción történo pszichometriai és klinikometriai vizsgálat által a perifériás veroérbetegek életminoségének, szubjektív betegségterhének felmérését célzó validálásra. Orv Hetil. 2020; 161(51): 2153-2161. INTRODUCTION: Peripheral artery disease is one of the greatest, global public health concerns affecting more than 200 million people worldwide. The Peripheral Artery Disease Quality of Life questionnaire was developed to assess the subjective disease burden of peripheral artery disease, by focusing on psychosocial and emotional effects besides physical symptoms and functional limitations. OBJECTIVE: To develop the valid Hungarian version of the original PADQOL via the standard linguistic validation and cross-cultural adaptation procedure. METHODS: The linguistic validation was conducted according to an international protocol: two independent forward translations, a synthesis of the translations, back translations and consensus team review. The pilot-testing of the 'pre-final' Hungarian version was conducted via cognitive interviews with 30 in- and outpatients attending the Department of Angiology. Factor analysis was performed, Cronbach-alpha values were calculated to establish the reliability of subscales and to determine the internal consistency if items. IBM SPSS 23.0 was used. RESULTS: The linguistic validation of PADQOL into Hungarian posed no difficulties in terms of semantic, experiential and idiomatic equivalence. One item was found difficult to interpret during cognitive interviewing. The 'pre-final' version of the questionnaire was easy to understand and complete. Cronbach-alpha values of factors ranged between 0.624 and 0.887. The lowest value was that of factor 4: Fear and Uncertainty (mean score: 14.07). CONCLUSION: The linguistic validation of PADQOL into Hungarian was successful, the final Hungarian version is a tool that should reveal valuable insights with regard to subjective disease burden of patients living with peripheral artery disease subsequent to psychometric and clinicometric validation on a larger patient population. Orv Hetil. 2020; 161(51): 2153-2161.

Lower limb ischemia and microrheological alterations in patients with diabetic retinopathy.

BACKGROUND: Diabetes mellitus is frequently associated with vascular pathologies and hemorheological disorders. METHODS: 105 patients with diabetic retinopathy (DRP) (mean age 64.64±9.01 years, 56 males, 49 females), 35 age-matched non-diabetic (mean age 61.65±7.6 years, 14 males and 21 females) and 42 young healthy volunteers (mean age 25.52±3.32 years, 22 males, 20 females) were recruited. Lower extremity artery disease (LEAD) and microcirculatory alterations were screened by hand-held Doppler, transcutaneous partial tissue oxygen tension (tcpO2), tuning fork test, 6-minute walk test, erythrocyte aggregation and deformability. RESULTS: High prevalence of LEAD was detected in diabetic population: 55.3% fulfilled the criteria of LEAD based on ankle-brachial index; severely impaired tcpO2 was measured in 18.6%. The results of non-invasive measurements of the diabetic patients were significantly worse than those of the control groups (p < 0.05). Hemorheological disturbances could be characterized by the significantly higher erythrocyte aggregation (p < 0.05) and lower erythrocyte deformability (p < 0.05) in the diabetic population. CONCLUSION: Macro- and microcirculatory lower limb disorders could be revealed at high prevalence in diabetic patients with retinopathy. Measurement of tcpO2 and hemorheological variables could be useful to discover patients at higher risk for diabetic foot complications.

Viscometer validation studies for routine and experimental hemorheological measurements.

BACKGROUND: Viscosity measurement is challenging due to the internal properties of blood and the artifacts deriving from the various viscometer systems. OBJECTIVE: We aimed to determine the pitfalls of a cone-plate viscometer (Brookfield DV-III Ultra LV) before starting measurements and compare it to our capillary type model (Hemorex Hevimet 40). Effects of sample storage and thermal calibration were assessed as well. METHODS AND RESULTS: Intra-observer variability was studied by 10 replicate measurements of 7 blood samples, mean coefficients of variation were less than 5%. Instruments were compared by measuring 26 blood samples, an average difference of 7% in WBV and 10% in PV was observed. 9 blood samples were stored at 4°C, 22°C and 37°C up to 48 hours to study the effect of storage on viscosity values. WBV at 50 and 100 s-1 became significantly lower after 3 hours at 37°C (p < 0.05). WBV at higher shear rates and PV remained constant at all temperatures. To evaluate the possibility of measuring one sample at different temperatures, 8 blood samples were measured at 40°C with the device calibrated both at 20°C and 40°C; no significant difference was observed. CONCLUSIONS: Thorough validation studies are required before starting experimental and routine viscosity measurements.

Toe-brachial index and exercise test can improve the exploration of peripheral artery disease.

BACKGROUND AND AIMS: We assumed that hand-held Doppler ultrasound (DUS) at rest was insufficient to assess the severity of peripheral artery disease (PAD). Toe pressure and transcutaneous tissue oxygen pressure were studied to prove whether these could identify more patients with severe lower limb ischemia; exercise was applied to provoke ischemia. METHODS: 120 patients with PAD and 30 volunteers without PAD were recruited. DUS, transcutaneous tissue oxygen pressure (tcpO2) and toe pressure measurements were performed at rest and after exercise. The differential power of these examinations for severe limb ischemia (SLI) was determined by receiver-operating curves (ROCs) and pattern recognition by independent multicategory analysis (PRIMA). RESULTS: There was an obvious significant difference between the patient and control groups at rest; after exercise; the ratio of severely impaired values (ankle-brachial index - ABI, toe-brachial index - TBI, tcpO2 measured on index forefoot) increased significantly in the patient group (p < 0.05). TBI, tcpO2, ABI measured after exercise could differentiate SLI better than the values of these tests at rest (p < 0.001). In ROC analysis, the largest area under the curve (AUC) was covered by post- (AUC: 0.860) and pre-exercise TBI (AUC: 0.785), and post-exercise tcpO2 (AUC: 0.720) (p < 0.001). Post-exercise TBI gained the best discriminant score in PRIMA. CONCLUSIONS: Pre- and post-exercise non-invasive vascular tests could reveal severe limb ischemia. Toe pressure measurement and TBI should become a basic part of the vascular workup.

The relationship between hemorheological parameters and mortality in critically ill patients with and without sepsis.

PURPOSE: The prognostic scoring systems for mortality of intensive care patients estimate clinical outcome using several physiological and biochemical parameters. In altered hemodynamic conditions of critically ill patients, hemorheological variables may play a significant role in appropriate tissue perfusion. We investigated if hemorheological parameters are altered in critical status and if they could be markers of mortality. METHODS: 112 patients (67.8 ± 12 years, 58 males, 54 females) treated in intensive care unit with different non-surgical diseases were investigated. Routine laboratory parameters and prognostic scores were determined and hemorheological variables (hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability) were measured on the 1st and the 2nd day after admission. RESULTS: ICU scores predicted 35.2-41.3% mortality rate, real mortality in intensive care unit was 37.5%, while 30-day mortality was 46.6%. Whole blood viscosity (WBV) and red blood cell (RBC) deformability were lower, red blood cell aggregation was higher in septic than in nonseptic patients (p < 0.05). In septic patients calcium was increased, osmolality was decreased, while in nonseptic patients WBV and RBC aggregation were higher in nonsurvivors compared to survivors (p < 0.05). Worsening of RBC deformability from day 1 to day 2 predicted higher mortality (p < 0.05). CONCLUSION: Calcium and osmolality level were associated with outcome in sepsis. Whole blood viscosity, red blood cell aggregation and change in red blood cell deformability could predict mortality in nonseptic patients and they may add prognostic information over the ICU scores. Further investigations are needed to evaluate the benefit of our findings in clinical practice.

Altered microrheological parameters in Raynaud's phenomenon.

Raynaud's phenomenon is an episodic, painful attack of the acral parts caused by local diminished blood supply. The aim of our study was to examine hemorheological parameters, cold agglutinins, cryoglobulins and their relationship in patients suffering from Raynaud's phenomenon.Blood was taken from 74 patients (mean age: 48 years, female/male: 56/18). Cold agglutinins and cryoglobulins were determined. Hemorheological parameters were also measured such as hematocrit, plasma and whole blood viscosity, red blood cell aggregation and deformability. Results were compared to a group of 58 healthy controls (mean age: 31.5 years, female/male: 24/34).Cold agglutinins were positive in 70%, cryoglobulins in 43% of patients. When compared to healthy controls, increased red blood cell aggregation (64.54  ±  8.93 vs. 61.11  ±  7.05) and decreased red blood cell deformability (0.669  ±  0.002 vs. 0.681  ±  0.001) was observed in Raynaud's patients (p < 0.05), but there were no differences in hematocrit (43.27% ± 3.85 vs. 44.10% ± 3.70), plasma (1.27 mPas ± 0.08 vs. 1.24 mPas ± 0.09) and whole blood viscosity (4.12 mPas ± 0.52 vs. 4.26 mPas ± 0.46). No differences were found between the hemorheological profile of cold agglutinin/cryoglobulin positive and negative patients. Also primary and secondary Raynaud's patients had similar rheological profile.Erythrocyte aggregation and deformability seems to be unfavorable in Raynaud's patients that can play a role in the disturbance of the microcirculation.

Hemorheological alterations in carotid artery stenosis.

BACKGROUND: Carotid artery stenosis (CAS) is not only an important risk factor of cerebrovascular events but it can also indicate generalized atherosclerosis. Hemorheological parameters are altered in CAS and in chronic cerebrovascular disorders as well, but it is controversial if hemorheological parameters could be markers of stenosis or atherosclerosis. METHODS: 107 patients were investigated, 40% of them had stroke or TIA in case history and 48% had CAS. Routine lab parameters were determined and hemorheological variables were measured: hematocrit, plasma viscosity, whole blood viscosity, red blood cell aggregation, and deformability. RESULTS: In the stenotic group whole blood viscosity and red blood cell aggregation were deteriorated (p < 0.05). Whole blood and plasma viscosity were higher and red blood cell deformability was lower in the symptomatic group (p < 0.05). Plasma viscosity and red blood cell deformability were altered in the evolving atherosclerosis group and the CAS groups compared to patients having no signs of stenosis (p < 0.05), but there was no difference among the CAS groups. CONCLUSION: Although hemorheological parameters are impaired both in CAS and chronic cerebrovascular disorders, the severity of stenosis cannot be detected based on hemorheological parameters. Our investigation suggests that alteration of hemorheological parameters could indicate carotid atherosclerosis.

[Investigation of vasoactive agents with indole skeletons at Richter Ltd]. / Indolvázas vegyületek kutatása a Richterben.

Investigation of agents with indol skeleton was started in Richter Ltd. 50 years ago. This paper presents the results obtained by Richter's scientists. At first, a vasoactive alcaloid, vincamine was extracted from the leaves of Vinca minor in industrial quantity in 1955. This agent selectively improves the cerebral blood supply. Vincamine (Devincan) is used for the treatment of cerebrovascular disorders from 1959. Vinpocetine (Cavinton), the most powerful vasoactive compound was produced by transforming the chemical structure of vincamine. Cavinton is a cis(3S,16S)-derivate of vincamine having antianoxic, antiischaemic and neuroprotective properties. Therefore, it is frequently used in the therapy of cerebral disorders of vascular origin. Cavinton was introduced into clinical practice in 1978. At present, Cavinton tablets are approved in 47 countries. The third compound, vintoperol is a trans(3S,16R)-derivate of vincamine. Vintoperol proved to be a powerful enhancer of blood flow in the lower extremities. Because of its toxic side effects the agent is not used in clinical practice.

[Investigation of neuromuscular blocking agents at Richter Ltd]. / Szteroid izomrelaxánsok kutatása a Richterben.

Investigation of new neuromuscular blocking agents was started 30 years ago in Richter Ltd. This paper presents the results obtained by Richter's scientists. 2 compounds out of 100 bisquaternary ammonio steroid having androstane skeleton were selected for further pharmacological study. One of these agents, pipecuronium bromide (Arduan) elicited long-lasting block of neuromuscular transmission without cardiovascular side effects in both animal experiments and clinical studies. Arduan is a powerful competitive antagonist of acetylcholine, since it can bind pre- and postsynaptic (N1) receptors of the transmitters. It has no remarkable cumulative effect. Neostigmine rapidly and completely antagonized the neuromuscular blockade caused by pipecuronium. Arduan was introduced into clinical practice. The second compound, RGH-4201 (Duador) evoked a neuromuscular block of short duration. It showed slight atropin-like cardio-vagolytic effect in animal experiments. In the clinical studies, however, the cardiovascular side effects were found to be too strong. Therefore, it was not introduced in clinical practice.

Effect of BRX-220 against peripheral neuropathy and insulin resistance in diabetic rat models.

Bimoclomol (BML), a symptomatic antidiabetic agent, has been developed by Biorex R & D Co. to treat diabetic neuropathy and retinopathy. BRX-220, an orally active member of the BRX family, has been developed to treat diabetic complications and insulin resistance (IR) as a follow-up compound. The effect of BRX-220 on peripheral neuropathy was examined in rats with diabetes (type 1) induced by administration of a beta-cell toxin, streptozotocin (STZ, 45 mg/kg iv). Nerve functions were evaluated by electrophysiological measurements of muscle motor and sensory nerve conduction velocities (MNCV and SNCV, respectively). MNCV and SNCV decreased in diabetic rats by 25% (p < 0.001). A 1-month preventive treatment with BRX-220 (2.5, 5, 10, and 20 mg/kg po) dose-dependently improved diabetes-related deficits in MNCV (51.3%, 71.3%, 86.1%, and 91.3%) and SNCV (48.9%, 68.5%, 86.1%, and 93.2%). Insulin sensitivity was measured using the insulin tolerance test (ITT), both in STZ diabetic and in Zucker diabetic fatty (ZDF) rats (model of type 2 diabetes). Severe IR was detected in STZ diabetic and ZDF rats. This resistance was significantly (p < 0.05) reduced by BRX-220 treatment.