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Dive into the research topics where Christopher R. Lattimer is active.

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Featured researches published by Christopher R. Lattimer.


European Journal of Vascular and Endovascular Surgery | 2014

Quantifying the degree graduated elastic compression stockings enhance venous emptying.

Christopher R. Lattimer; Evi Kalodiki; Marina Kafeza; M. Azzam; George Geroulakos

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.


Journal of Vascular Surgery | 2013

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

Christopher R. Lattimer; Mustapha Azzam; Evi Kalodiki; Gregory C. Makris; George Geroulakos

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.


Phlebology | 2014

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

Christopher R. Lattimer; M. Azzam; Evi Kalodiki; George Geroulakos

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.


Phlebology | 2013

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

Christopher R. Lattimer; Evi Kalodiki; M. Azzam; George Geroulakos

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.


Angiology | 2014

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

Christopher R. Lattimer; Evi Kalodiki; Mustapha Azzam; George Geroulakos

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.


Journal of vascular surgery. Venous and lymphatic disorders | 2013

Validation of the Villalta scale in assessing post-thrombotic syndrome using clinical, duplex, and hemodynamic comparators.

Christopher R. Lattimer; Evi Kalodiki; Mustapha Azzam; George Geroulakos

Introduction: The Villalta scale (VS) was developed by Prandoni and introduced as an abstract in 1994 as a diseasespecific assessment questionnaire to diagnose and classify the severity of post-thrombotic syndrome (PTS). While validation using quality-of-life assessments and reproducibility have been reported as good, limited data exist as how the VS compares against generalized assessment tests in defining the severity of PTS. The aim of this study was to compare the VS against the Venous Clinical Severity Score (VCSS), the C of the CEAP classification, the Venous Segmental Disease Score (VSDS), and the Venous Filling Index (VFI) of air plethysmography. Methods: Baseline data generated from a recent single-center prospective clinical trial comparing graduated elastic compression stocking performance on 40 legs in 34 patients with PTS were analyzed. Ancillary data from this study were used to assess the measurement properties of the VS. All the legs had PTS defined as persisting leg symptoms/signs at least 6 months after a deep vein thrombosis with evidence of deep venous obstruction and/or deep venous reflux on duplex ultrasound. Unadjusted VS scores were used so patients with ulceration with a VS <15 were not automatically upgraded to a score of 15.


Journal of Vascular Surgery | 2012

Saphenous pulsation on duplex may be a marker of severe chronic superficial venous insufficiency

Christopher R. Lattimer; M. Azzam; Evi Kalodiki; Gregory C. Makris; George Geroulakos

BACKGROUND Pulsatile flow in deep, perforating veins and varicose veins (VVs) has been described previously to support a hypothesis of arteriovenous (AV) fistulae in the pathogenesis of VVs. Its presence has also been suggested as a cause of failure of VV treatments. However, AV communications have never been adequately visualized and direct pressure tracings within leg veins have been inconclusive. The present study was observational aiming to investigate the prevalence and rate of spontaneous pulsation within the great saphenous vein (GSV) in volunteers and patients using color duplex and compare this to reflux and markers of disease severity. METHODS Twenty-seven consecutive patients (32 legs, median Venous Clinical Severity Score (VCSS) = 5 [0-11]) attending the VV clinic and 23 consecutive ambulatory normal volunteers (46 legs) had their GSV assessed at midthigh using color duplex. Subjects were examined standing with the hips resting against an adjustable couch, bearing weight on the contralateral leg, with the test leg touching the ground. The presence of flow and reflux were initially determined using manual calf compression. Saphenous pulsation (SP) was defined as a cyclical change in velocity. The GSV diameter and SP rate were then recorded after 2 minutes of dependency. The number of pulsations was counted from video recordings. RESULTS The resting SP, if present, was discrete, monophasic, of variable amplitude, antegrade, and irregular, irrespective of respiration. Pulsation was detected in 2/44 (4.5%) legs with C(0-1) (C part of CEAP), 9/17 (52.9%) legs with C(2-3), and 16/17 (94.1%) legs with C(4-6) (P < .05, z test of column proportions). Reflux occurred in 8/32 (25%) legs without SP (C(0) = 2, C(1) = 1, C(2) = 3, C(3) = 2). The median GSV diameter was significantly elevated in the presence of SP (no pulse: 3.5 [range, 1.5-8.1] mm; pulse: 7 [range, 4-9.4] mm; P < .0005). The median refluxing GSV diameter in GSV pulsators compared with nonpulsators was 7 (range, 4-9.4) mm; vs 5.1 (range, 2.7-8.1) mm, respectively (P = .003). The median SP rate in refluxing GSVs was 52 (range, 22-95) beats per minute. CONCLUSIONS The high prevalence of pulsatile antegrade saphenous flow is a novel observation in patients with severe superficial chronic venous insufficiency. It is detectable in 75% of patients with GSV reflux and significantly increases with clinical severity and saphenous diameter. It may be a marker of advanced venous disease and, as it is easy to record, it could supplement duplex evaluations of reflux. Further work is needed to establish the clinical relevance of the SP in terms of disease progression, recurrence after treatment, and as a hemodynamic marker of severity.


Clinical and Applied Thrombosis-Hemostasis | 2016

Are Inflammatory Biomarkers Increased in Varicose Vein Blood

Christopher R. Lattimer; Evi Kalodiki; George Geroulakos; Debra Hoppensteadt; Jawed Fareed

Objectives: To test for the presence of inflammatory biomarkers in blood taken from varicose veins versus antecubital blood of the same patient and compare this to levels in healthy controls. Methods: Using a multiplex biochip array method (Randox, United Kingdom), the interleukins (ILs) IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-8, and IL-10; vascular endothelial growth factor; interferon γ, tumor necrosis factor α ; monocyte chemotactic protein 1 (MCP-1); and epidermal growth factor were measured in citrated plasma samples drawn from the arms and legs of 24 patients with varicose veins and 24 controls. Results: Expressed as median (interquartile range) in pg/mL, leg samples from patients with varicose veins had significantly higher levels of IL-8 and MCP-1 compared to their own arm samples (IL-8: local 2.3 [1.71-3.3] vs systemic 2.3 [1.62-2.98], P = .023; MCP-1: local 114.42 [84.29-139.05] vs systemic 103.56 [79.75-126.42], P < .0005). This was not observed in the control group. Leg samples from both patients with varicose vein and controls had higher levels of IL-6 compared to their own arm samples (patients: local 1.67 [0.82-4.48] vs systemic 1.24 [0.58-3.26], P = .002; controls: local 1.23 [0.83-1.7] vs systemic 1.03 [1.7-1.52], P = .005). No significant differences were detected with the other biomarkers. Conclusions: Blood drawn from the site of varicose veins appears to have significantly increased concentrations of IL-6, IL-8, and MCP-1 when compared to the same patient’s arm blood. This supports the hypothesis that inflammation is activated from the tissues drained by the varicose veins.


Phlebology | 2014

Responsiveness of individual questions from the venous clinical severity score and the Aberdeen varicose vein questionnaire.

Christopher R. Lattimer; Evi Kalodiki; M. Azzam; George Geroulakos

Objectives The venous clinical severity score (VCSS) and the Aberdeen varicose vein questionnaire (AVVQ) improve after treating chronic venous insufficiency (CVI). The aim was to examine how and why they improve by evaluating the change in each individual question. Methods This was an analysis on prospectively collected data from a clinical study on 100 patients (58% female) with CVI (C2 = 34, C3 = 14, C4a = 29, C4b = 9, C5 = 7, C6 = 7) who were randomized to endovenous laser ablation (n = 50) or foam sclerotherapy (n = 50). The change scores (performance) of each question of the VCSS (questions 1–10) and the AVVQ (questions 1–13) were calculated by subtracting the score at three weeks, and three months, from the pre-treatment score. Results Both the median, interquartile range (IQR), VCSS and the AVVQ scores improved from 6 (4) and 21.4 (15.1) at baseline to 3 (4) and 18.6 (12.1) at three weeks (P < 0.0005, P = 0.031) to 2 (3) and 8.8 (13.6) at three months, (P < 0.0005, P < 0.0005), respectively. The performance of the first three questions of the VCSS (pain, extent of varicosities, oedema) were the most contributory to the overall score. Questions 5, 7, 8, 9 on ulceration improved the most individually but did not contribute significantly to the overall score. Questions 5, 9 of the AVVQ on stocking use and ulceration failed to contribute statistically to the overall improvement at three months. Conclusion The majority of the individual questions of the VCSS and AVVQ responded to change. However, the cause of a poor response was multifactorial with statistical dilution playing a significant role. Stratification of patients according to ulceration may allow better comparisons.


European Journal of Vascular and Endovascular Surgery | 2017

A Review of Open and Endovascular Treatment of Superior Vena Cava Syndrome of Benign Aetiology

G.S. Sfyroeras; C.N. Antonopoulos; G. Mantas; Konstantinos G. Moulakakis; John Kakisis; Elias Brountzos; Christopher R. Lattimer; George Geroulakos

BACKGROUND The widespread use of central venous catheters, ports, pacemakers, and defibrillators has increased the incidence of benign superior vena cava syndrome (SVCS). This study aimed at reviewing the results of open and endovascular treatment of SVCS. METHOD Medical literature databases were searched for relevant studies. Studies with more than five adult patients, reporting separate results for the SVC were included. Nine studies reported the results of endovascular treatment of SVCS including 136 patients followed up for a mean of 11-48 months. Causes of SVCS were central venous catheters and pacemakers (80.6%), mediastinal fibrosis (13.7%), and other (5.6%). Percutaneous transluminal angioplasty (PTA) and stenting was performed in 73.6%, PTA only in 17.3%, and thrombolysis, PTA, and stenting in 9%. Four studies reported the results of open repair of SVCS including 87 patients followed up between 30 months and 10.9 years. The causes were mediastinal fibrosis (58.4%), catheters and pacemakers (28.5%), and other (13%). Operations performed included a spiral saphenous interposition graft, other vein graft, PTFE graft, and human allograft. Thirteen patients required re-operations (15%) before discharge mainly for graft thrombosis. RESULTS In the endovascular group technical success was 95.6%. Thirty day mortality was 0%. Regression of symptoms was reported in 97.3%. Thirty-two patients (26.9%) underwent 58 secondary procedures. In the open group the 30 day mortality was 0%. Symptom regression was reported in 93.5%. Twenty-four patients (28.4%) underwent a total of 33 secondary procedures. CONCLUSIONS Endovascular is the first line treatment for SVCS caused by intravenous devices, whereas surgery is most often performed for mediastinal fibrosis. Both treatments show good results regarding regression of the symptoms and mid-term primary patency, with a significant incidence of secondary interventions.

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Evi Kalodiki

Imperial College London

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M. Azzam

Imperial College London

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Erika Mendoza

Sapienza University of Rome

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Jawed Fareed

Loyola University Medical Center

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Debra Hoppensteadt

Loyola University Medical Center

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Paul Trueman

Brunel University London

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Konstantinos G. Moulakakis

National and Kapodistrian University of Athens

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