Evi Kalodiki

Stroke: epidemiology, clinical picture, and risk factors--Part I of III.

The aim of this review is to present the current knowledge regarding stroke. It will appear in three parts (in part II the pathogenesis, investigations, and prognosis will be presented, while part III will consist of the management and rehabilitation). In the current part (I) the definitions of the clinical picture are presented. These include: amaurosis fugax, vertebrobasilar transient ischemic attack, and stroke (with good recovery, in evolution and complete). The role of the following risk factors is discussed in detail: age, gender, ethnicity, heredity, hypertension, cigarette smoking, hyperlipidemia, diabetes mellitus, obesity, fibrinogen and clotting factors, oral contraceptives, erythrocytosis and hematocrit level, prior cerebrovascular and other diseases, physical inactivity, diet and alcohol consumption, illicit drug use, and genetic predisposition. In particular, regarding the carotid arteries, the following characteristics are analyzed: atheroma, carotid plaque echomorphology, carotid stenosis, presence of ulcer, local variations in surface deforma bility, pathological characteristics, and dissection. Finally the significance of the cerebral collateral circulation and the conditions predisposing to cardioembolism and to cerebral hemorrhage are presented.

The Genesis of Atherosclerosis and Risk Factors: A Review

Atherosclerosis constitutes the most common medical and surgical problem. This can be mani fested clinically as stroke, coronary artery disease, or peripheral vascular disease. In the present review the microscopic appearance of the normal arterial wall, the definition of atherosclerosis and the five theories of atherogenesis are described. These are: the lipid theory, the hemody namic theory, the fibrin incrustation theory, the nonspecific mesenchymal hypothesis and the response to injury hypothesis. Based on the above theories the sequence of events in athero genesis is analyzed. The classification of the atherosclerotic lesions according to Stary (types I-VI) and their characteristics appear in a table. The epidemiology and the role of the following risk factors are presented in detail: age, sex, lipid abnormalities, cigarette smoking, hyperten sion, diabetes mellitus, physical inactivity, alcohol consumption, obesity, and hemostatic factors. In addition, less common genetically determined associations like homocystinuria, Tangier disease, Hutchinson-Gilford syndrome (progeria), Werners syndrome, radiation induced ather osclerosis and the implications of Chlamydia pneumoniae on the arterial wall are discussed.

Make it Easy: Duplex Examination of the Venous System

Objective: A methodological report of duplex ultrasound examination of the venous system, with Particular consideration of the best position for examining the patient. Design: Single patient group, comparison of duplex ultrasound imaging with phlebography. getting: Teaching hospital vascular laboratory. Patients: Patients referred for assessment of their venous system. Main outcome measures: Duplex ultrasound scanning of the lower limb, ascending phlebography. Results: Our results of duplex ultrasound scanning in the diagnosis of deep vein thrombosis as compared with Phlebography show a sensitivity of 94% and a specificity of 91%. Conclusions: We found it advantageous to examine the Patient standing during proximal vein imaging and sitting for distal venous examination. Veins dilated as a result of gravitational effects are visualized more easily. The examiner, by resting the elbow on his/her distal Thigh, has a more stable hand, facilitating the test. The Patient, by resting the heel on the edge of the examiners chair, relaxes the calf muscles, thus simplifying the augmentation manoeuvre. The inflation of a tourniquet applied to the distal thigh dilates the calf veins.

Quantifying the degree graduated elastic compression stockings enhance venous emptying.

OBJECTIVES Graduated elastic compression (GEC) stockings reduce reflux and venous volume but their performance on augmenting venous return is unproven. The aim of this study was to quantify the ability of stockings to increase venous outflow from the leg. DESIGN A prospective study comparing venous emptying without compression, versus class 1 (18-21 mmHg) and class 2 (23-32 mmHg) compression, using air-plethysmography (APG). METHODS The right legs of 20 healthy subjects were studied supine. A 12-cm thigh-cuff was inflated in 10 mmHg steps from 0 to 80 mmHg while the corresponding increase in calf volume was recorded using the APG sensor calf-cuff. At the 80 mmHg plateau, the thigh-cuff was released suddenly to measure the unrestricted venous emptying. Venous return was assessed by: (a) identifying the incremental thigh-cuff pressure causing the maximal incremental increase in calf volume (IPMIV); (b) measuring the percentage reduction in calf volume in 1 second following thigh-cuff release - outflow fraction (OF); (c) time to empty 90% of the venous volume - venous emptying time (VET90). RESULTS Median and inter-quartile range (IQR) baseline values of IPMIV, OF, and VET90 without compression were 20 mmHg (range: 20-30 mmHg), 44% (39-50%) and 13 seconds (8.8-15.9 seconds), respectively. These improved significantly with all stockings. The application of any stocking raised the median IPMIV by 30 mmHg. The change from a class 2 stocking compared with no stocking versus the change from a class 1 stocking to no stocking had a more pronounced effect (p < .005). After sudden thigh-cuff deflation, the venous emptying was 41-45% greater and 9-10 seconds faster with all stockings (p < .005). CONCLUSIONS This is the first study to quantify the venous return of below-knee GEC stockings. Assessments of stockings in augmenting venous return may be of use as a way of optimising compression for individual patients unresponsive to standard conservative treatment.

Interpretation of Benefit-Risk of Enoxaparin as Comparator in the RECORD Program: Rivaroxaban Oral Tablets (10 milligrams) for Use in Prophylaxis in Deep Vein Thrombosis and Pulmonary Embolism in Patients Undergoing Hip or Knee Replacement Surgery

The Regulation of Coagulation in Major Orthopedic surgery reducing the Risk of DVT and PE (RECORD) clinical program of rivaroxaban consists of 4 phase III clinical trials comparing rivaroxaban with enoxaparin for the prevention of venous thromboembolism (VTE) in patients undergoing either total hip or total knee replacement surgery. Despite the comprehensive and extensive nature of this program, it had some logistic issues that included the dosing of the enoxaparin which was not only inconsistent with the recommendations but the dosages used were not optimal. The duration of treatment while consistent with rivaroxaban did vary with enoxaparin and was somewhat short. The bleeding definitions and safety evaluations were not consistent in accordance with the current recommendations. Moreover, the RECORD program has no power to show differences in major bleeding. The cardiovascular rebound phenomenon should have been adequately addressed and may require additional clinical validation to establish the safety of rivaroxaban. Although the US Food and Drug Administration (FDA) advisory committee has recommended approval of rivaroxaban, the reported analysis strongly suggests additional clinical validation on the claimed benefit/risk ratio of this monotherapeutic anticoagulant.

Compression stockings significantly improve hemodynamic performance in post-thrombotic syndrome irrespective of class or length

BACKGROUND Graduated elastic compression (GEC) stockings have been demonstrated to reduce the morbidity associated with post-thrombotic syndrome. The ideal length or compression strength required to achieve this is speculative and related to physician preference and patient compliance. The aim of this study was to evaluate the hemodynamic performance of four different stockings and determine the patients preference. METHODS Thirty-four consecutive patients (40 legs, 34 male) with post-thrombotic syndrome were tested with four different stockings (Mediven plus open toe, Bayreuth, Germany) of their size in random order: class 1 (18-21 mm Hg) and class II (23-32 mm Hg), below-knee (BK) and above-knee thigh-length (AK). The median age, Venous Clinical Severity Score, Venous Segmental Disease Score, and Villalta scale were 62 years (range, 31-81 years), 8 (range, 1-21), 5 (range, 2-10), and 10 (range, 2-22), respectively. The C of C0-6EsAs,d,pPr,o was C0 = 2, C2 = 1, C3 = 3, C4a = 12, C4b = 7, C5 = 12, C6 = 3. Obstruction and reflux was observed on duplex in 47.5% legs, with deep venous reflux alone in 45%. Air plethysmography was used to measure the venous filling index (VFI), venous volume, and time to fill 90% of the venous volume. Direct pressure measurements were obtained while lying and standing using the PicoPress device (Microlab Elettronica, Nicolò, Italy). The pressure sensor was placed underneath the test stocking 5 cm above and 2 cm posterior to the medial malleolus. At the end of the study session, patients stated their preferred stocking based on comfort. RESULTS The VFI, venous volume, and time to fill 90% of the venous volume improved significantly with all types of stocking versus no compression. In class I, the VFI (mL/s) improved from a median of 4.9 (range, 1.7-16.3) without compression to 3.7 (range, 0-14) BK (24.5%) and 3.6 (range, 0.6-14.5) AK (26.5%). With class II, the corresponding improvement was to 4.0 (range, 0.3-16.2) BK (18.8%) and 3.7 (range, 0.5-14.2) AK (24.5%). Median stocking pressure (mm Hg) as measured with the PicoPress in class I was 23 (range, 12-33) lying and 27 (range, 19-39) standing (P < .0005) and in class II was 28 (range, 21-40) lying and 32 (range, 23-46) standing (P < .0005). There was a significant but weak correlation (Spearman) between stocking interface pressure measured directly with the PicoPress and the VFI improvement (baseline VFI-compression VFI) at r = .237; P = .005. Twenty-one patients (legs) changed their preference of compression and 38% of these (8/21 patients, 9/21 legs) preferred an AK-GEC stocking. CONCLUSIONS Compression significantly improved all hemodynamic parameters on air plethysmography. However, the hemodynamic benefit did not significantly change with the class or length of stocking. These results support the liberal selection of a GEC stocking based on patient preference.

Duplex Scanning in Post-Operative Surgical Patients

The technique of duplex scanning for the diagnosis of deep venous thrombosis (DVT) has been developed in 3 stages. Initially B-mode imaging with compression was used. Subsequently interrogation of the venous lumen using the Doppler facility was introduced and finally the latter became simple and efficient with the introduction of colour flow imaging. Sensitivities and specificities in excess of 90% have been produced for thrombosis proximal to the calf by all methods in symptomatic patients. Colour flow imaging has given the best results for calf DVT in symptomatic patients with 86% sensitivity and 91% specificity. Before the introduction of colour flow imaging the accuracy for the detection of old thrombi in asymptomatic patients was poor. With the introduction of colour, sensitivities and specificities in excess of 90% have been obtained for proximal DVT; for calf DVT, sensitivity of 79% and specificity of 97% have been reported by 2 studies. If further studies substantiate these recent results duplex scanning will become the non-invasive method to be used in screening asymptomatic patients.

Venous filling time using air-plethysmography correlates highly with great saphenous vein reflux time using duplex

Objectives: Venous filling time (VFT90) is the time taken to reach 90% of the venous volume in the calf. It is recorded by air-plethysmography (APG®) and is assumed to measure global venous reflux duration. However, this has never been confirmed by duplex. The aim of the study was to compare VFT on APG to venous reflux time/duration (RT) measured simultaneously with duplex on the same patients. Method Twenty-six consecutive patients, M:F = 16:10, age (25–78), C1 = 1, C2 = 4, C3 = 8, C4a = 6, C4b = 4, C5 = 2, C6 = 1, underwent simultaneous APG with duplex. The venous filling index (VFI, mL/second), VFT90 (seconds), great saphenous vein (GSV) RT on duplex, averaged thigh GSV diameter and thigh length (length) between the APG sensor air-cuff and duplex transducer were recorded. The VFT100 was calculated by VFT90/0.9. The additional time taken to fill the thigh was achieved using the VFI, length and deep vein diameter (d), to determine the corrected reflux duration: CRD = VFT100 + (length × πd2/4 (1/VFI)). Results Twenty-five patients are presented. One patient with very mild reflux (VFT90 = 55.9 seconds) had an indeterminate endpoint on duplex and was excluded. The median (range) VFI and GSV diameter was 4.9(1.3–15.5) mL/second and 7(4–17) mm, respectively. The VFT90 and VFT100 both correlated with RT on duplex (Spearman, P < 0.0005) at: r = 0.933, r2 linear = 0.72 and r = 0.933, r2 linear = 0.68, respectively. The median (interquartile range) filling time with VFT90 was less than the duplex RT at 24 (16.9) versus 28 (20) seconds respectively P < 0.0005 (Wilcoxon). The median percentage underestimation improved from 24% to 16% and then 4% using the VFT90, VFT100 and CRD, respectively. Conclusions This is the first study to compare APG parameters with duplex by performing simultaneous measurements. There was an excellent correlation between the VFT90 versus duplex RT, thereby comparing reverse flow in a single superficial vein against the legs overall venous haemodynamic status. These tests can both be used in the quantification of reflux.

Reflux time estimation on air-plethysmography may stratify patients with early superficial venous insufficiency.

Objectives It has been suggested that quantification of haemodynamic parameters of venous disease may complement clinical assessment and may help identify a group of patients with severe venous disease or alternatively patients with early venous disease. However, there has been very little work to prove this hypothesis. The venous filling index (VFI) of air-plethysmography (APG) can quantify severity and treatment effect but has limited discriminatory value. However, the components of the VFI, total venous volume (VV) and time to reach 90% of VV (VFT90), have never been fully studied. The aim was to investigate the contribution of VV and VFT90 to an elevated VFI and determine their relationship to great saphenous vein (GSV) diameter and clinical severity scoring. Method Ninety-three consecutive patients/legs (22–78 years) with primary GSV reflux (>0.5 seconds) awaiting endovenous treatment were recruited. CEAP (clinical, aetiological, anatomical and pathological elements) assessments were: 33 (35.5%) C2, 14 (15.0%) C3, 29 (31.2%) C4a, 5 (5.4%) C4b, 7 (7.5%) C5 and 5 (5.4%) C6. The median venous clinical severity score (VCSS) was 6 (2–20) and the averaged GSV diameter at three sites was 7.5 mm (4–12). The VFI, VV and VFT90 were recorded using APG. Results There was no correlation between the VV and the VFT90 (r = −0.103, P = 0.324). The VFI, VV and VFT90 significantly correlated (P < 0.0005, Spearman) with the GSV diameter: r = 0.623, r = 0.567, r = −0.432, respectively, and the C of CEAP (P < 0.05): r = 0.4, r = 0.225, r = −0.343, respectively. None of the 25 (26.9%) patients with a VFT90 > 25 seconds were among the 17 (18.3%) patients in categories C4b–6 or with a VCSS > 9 (P = 0.005, Fishers exact test, corrected odds ratio: 17.3). Conclusions The VFT90 complements the VFI as a marker of severe superficial venous insufficiency. However, in contrast to the VFI, it may have discriminatory value in stratifying patients with early disease into two groups based on the severity of haemodynamic impairment.

The Aberdeen varicose vein questionnaire may be the preferred method of rationing patients for varicose vein surgery.

Rationing treatment of varicose veins (VVs) is of importance in countries with a public health service and limited funds. This study examines why and how the Aberdeen varicose vein questionnaire (AVVQ) can be used in achieving rationing. Baseline assessments prior to endovenous treatment included the venous clinical severity score (VCSS), venous filling index (VFI), and the refluxing great saphenous vein (GSV) diameter. Absolute change in the AVVQ defined improvement. There was no significant correlation in AVVQ improvement compared to baseline VCSS, VFI, GSV diameter or when patients were divided into mild and severe disease (C2,3 vs C4-6) or laser ablation versus foam sclerotherapy. However, AVVQ improvement significantly correlated at 3 weeks (n = 84) and 3 months (n = 70) with their baseline values (r = .5 and r = .585), P < .0005 (Spearman). In conclusion, patients with an initial poor quality of life may benefit most from endovenous treatment, irrespective of other baseline severity assessments.