Vincenzo Jacomella

Impact of obesity on venous hemodynamics of the lower limbs

BACKGROUND Obesity is a risk factor for chronic venous insufficiency and venous thromboembolism. The aim of this study was to compare venous flow parameters of the lower limbs assessed by duplex ultrasound scanning in obese and nonobese individuals according to body mass index (BMI). METHODS Venous hemodynamics were studied in a prospective cohort study in nonobese (BMI <25 kg/m(2)) and obese individuals (BMI >30 kg/m(2)). Diameter, flow volume, peak, mean, and minimum velocities were assessed. RESULTS The study examined 36 limbs in 23 nonobese individuals and 44 limbs in 22 obese individuals. The diameter of the femoral vein was significantly greater in obese (8.5 +/- 2.2 mm) vs nonobese (7.1 +/- 1.6 mm; P = .0009) limbs. Venous peak and minimum velocities differed between nonobese and obese individuals (14.8 +/- 7.2 vs 10.8 +/- 4.8 cm/s [P = .0071] and 4.0 +/- 3.6 vs 1.7 +/- 6.3 cm/s [P = .056]). Calculation of venous amplitude and shear stress showed significantly higher values in nonobese vs obese (18.8 +/- 9.4 vs 12.5 +/- 9.3 cm/s [P = .003] and 2.13 +/- 2.2 dyn/cm(2) vs 1.6 +/- 2.7 dyn/cm(2) [P = .03]). Spearman rank correlation revealed a significant inverse correlation between waist-to-hip ratios and waist circumference and venous peak velocity, mean velocity, velocities amplitude (peak velocity-minimum velocity), and shear stress. CONCLUSION Lower limb venous flow parameters differ significantly between healthy obese and nonobese individuals. These findings support the mechanical role of abdominal adipose tissue potentially leading to elevated risk for both venous thromboembolism and chronic venous insufficiency.

Novel anticoagulants in the therapy of peripheral arterial and coronary artery disease.

Anticoagulant and antiplatelet drugs are used and studied in numerous trials for primary and secondary prevention of atherothrombosis since decades. The annual rate for cardiovascular morbidity and mortality is high in patients following an acute coronary syndrome and in patients with peripheral arterial disease (PAD) due to concomitant cardiac and cerebrovascular diseases. Plaque rupture and subsequent thrombosis involves activation of both platelets and coagulation factors. Therefore the combination of aspirin and warfarin to improve prevention of atherothrombosis compared to antiplatelet therapy alone was studied but could not be established due to significantly increased risk of major bleeding compared to a nonsignificant reduction in ischemic events. During the past two decades, clinical trials focused on combined antiplatelet therapies for the prevention of secondary events following acute coronary syndromes and very recently on the new oral anticoagulants in combination with antiplatelet therapy. This review discusses the role of the new oral anticoagulants such as Factor IIa (thrombin) and Factor Xa inhibitors in atherothrombosis, their pharmacological properties and recently published clinical data in secondary prevention of atherothrombotic events and potential implications for patients with PAD.

Outpatient management of acute deep vein thrombosis: results from the OTIS-DVT registry.

OBJECTIVES We aimed to investigate clinical practice patterns for the outpatient management of acute deep vein thrombosis (DVT). METHODS In the prospective Outpatient Treatment of Deep Vein Thrombosis in Switzerland (OTIS-DVT) registry, 534 consecutive outpatients with acute DVT (49% proximal, 24% recurrent, and 12% cancer-associated) were enrolled: 41% patients were managed in private angiology practice, 34% in an outpatient hospital department, and 25% in private general or internal medicine practice. RESULTS For diagnosis, ultrasound was used in 95% and D-dimer testing in 53%. Low-molecular-weight heparin (LMWH) was prescribed for a median (IQR) duration of 7 (5-12) days in 83% of patients, and vitamin K-antagonists for 163 (92-183) days in 81%. Mechanical measures to prevent post-thrombotic syndrome were prescribed in 83%; compression stockings or bandages for a median (IQR) duration of 364 (101-730) days from hospital physicians, and 92 (45-183) days from private practice physicians (p < 0.001). Among patients with symptomatic proximal DVT, mechanical measures were prescribed for at least 2 years in 24% patients; 55% in hospital, and 6% in private practice (p < 0.001). Among patients with cancer-associated DVT, the median (IQR) duration of LMWH therapy was 16 (8-45) days, and 35% received LMWH for less than 90 days. CONCLUSIONS The OTIS-DVT registry provides representative information on clinical practice patterns for outpatients with acute DVT managed by hospital or private practice physicians. The use of mechanical measures in patients with symptomatic proximal DVT and the administration of LMWH for a long-term therapy of cancer-associated DVT require improvement to comply with current guidelines.

The Impact of Endovascular Lower-limb Revascularisation on the Aortic Augmentation Index in Patients with Peripheral Arterial Disease

OBJECTIVES The aortic augmentation index (AIx), a marker of arterial stiffness, and peripheral arterial disease (PAD) are associated with an increased cardiovascular risk. In claudicants, the effect of balloon angioplasty (percutaneous transluminal angioplasty, PTA) on AIx has not been determined so far. METHODS Measurements of the ankle-brachial pressure index (ABI) and AIx were performed before and 3 months after PTA and compared to age- and sex-matched PAD patients under best medical treatment. RESULTS The data of 61 patients (44% female, mean age 68 years) who underwent lower-limb PTA was compared to 48 conservatively treated patients (38% female, mean age 68 years). ABI significantly improved after PTA from 0.73 ± 0.02 to 0.85 ± 0.03 (p = 0.001), but remained unchanged in the control group (0.85 ± 0.23 and 0.80 ± 0.21; p = 0.16). Revascularisation was associated with a significant reduction of AIx from 31.5 ± 1.1% to 28.8 ± 1.1% after 3 months (p = 0.01). In the conservatively treated group, AIx did not change during follow-up (29.9 ± 1.1% to 29.9 ± 1.1%; p = 0.83). CONCLUSION Lower-limb revascularisation in PAD Rutherford stage II-III is associated with an improvement of markers for arterial stiffness.

Severity of peripheral arterial disease is associated with aortic pressure augmentation and subendocardial viability ratio

J Clin Hypertens (Greenwich). 2012; 14:855–860. ©2012 Wiley Periodicals, Inc.

Markers of arterial stiffness in peripheral arterial disease

Increased arterial stiffness results from reduced elasticity of the arterial wall and is an independent predictor for cardiovascular risk. The gold standard for assessment of arterial stiffness is the carotid-femoral pulse wave velocity. Other parameters such as central aortic pulse pressure and aortic augmentation index are indirect, surrogate markers of arterial stiffness, but provide additional information on the characteristics of wave reflection. Peripheral arterial disease (PAD) is characterised by its association with systolic hypertension, increased arterial stiffness, disturbed wave reflexion and prognosis depending on ankle-brachial pressure index. This review summarises the physiology of pulse wave propagation and reflection and its changes due to aging and atherosclerosis. We discuss different non-invasive assessment techniques and highlight the importance of the understanding of arterial pulse wave analysis for each vascular specialist and primary care physician alike in the context of PAD.

Risk Stratification of Patients with Peripheral Arterial Disease and Abdominal Aortic Aneurysm Using Aortic Augmentation Index.

Background Central augmentation index (cAIx) is an indicator for vascular stiffness. Obstructive and aneurysmatic vascular disease can affect pulse wave propagation and reflection, causing changes in central aortic pressures. Aim To assess and compare cAIx in patients with peripheral arterial disease (PAD) and / or abdominal aortic aneurysm (AAA). Methods cAIx was assessed by radial applanation tonometry (Sphygmocor) in a total of 184 patients at a tertiary referral centre. Patients were grouped as having PAD only, AAA only, or both AAA and PAD. Differences in cAIx measurements between the three patient groups were tested by non-parametric tests and stepwise multivariate linear regression analysis to investigate associations with obstructive or aneurysmatic patterns of vascular disease. Results In the study sample of 184 patients, 130 had PAD only, 20 had AAA only, and 34 patients had both AAA and PAD. Mean cAIx (%) was 30.5 ± 8.2 across all patients. It was significantly higher in females (35.2 ± 6.1, n = 55) than males (28.4 ± 8.2, n = 129), and significantly higher in patients over 80 years of age (34.4 ± 6.9, n = 22) than in those under 80 years (30.0 ± 8.2, n = 162). Intergroup comparison revealed a significant difference in cAIx between the three patient groups (AAA: 27.3 ± 9.5; PAD: 31.4 ± 7.8; AAA & PAD: 28.8 ± 8.5). cAIx was significantly lower in patients with AAA, higher in patients with both AAA and PAD, and highest in patients with PAD only (beta = 0.21, p = 0.006). Conclusion Non-invasive assessment of arterial stiffness in high-risk patients indicates that cAIx differs according to the pattern of vascular disease. Measurements revealed significantly higher cAIx values for patients with obstructive peripheral arterial disease than for patients with aneurysmatic disease.

Nitrous oxide/oxygen inhalation provides effective analgesia during the administration of tumescent local anaesthesia for endovenous laser ablation

BACKGROUND Tumescent anaesthesia (TA) is an important but sometimes very painful step during endovenous thermal ablation of incompetent veins. The aim of this study was to examine whether the use of fixed 50% nitrous oxide/oxygen mixture (N2O/O2), also called equimolar mixture of oxygen and nitrous oxide, reduces pain during the application of TA. PATIENTS AND METHODS Patients undergoing endovenous laser ablation (EVLA) of incompetent saphenous veins were included. Thirty consecutive patients inhaled N2O/O2 during the application of TA. Thirty consecutive patients received TA alone (controls). Patients were asked to complete a questionnaire immediately after the intervention to assess satisfaction with the intervention and pain-levels during the different steps of the intervention (0=not at all, 10=very much). Adverse events during the treatment were monitored. RESULTS 30 patients (14 men, mean age of 44 years) were included in the N2O/O2 group and 30 patients (9 men, mean age 48 years) were included in the control group. In the N2O/O2 group a significantly lower pain score was noted (mean 2.45 points, range 0-6) compared to the controls (mean 4.3 points, range 1-9, p<0.001). Overall, 64.5% of the patients were perfectly satisfied with the N2O/O2-Inhalation. Only 4 patients receiving N2O/O2 complained of adverse effects such as unpleasant loss of control (2 patients), headache (1 patient) and dizziness (1 patient). CONCLUSIONS N2O/O2 is a safe and effective method to reduce pain during the application of tumescent anaesthesia for EVLA.

Acute effects of haemodialysis on central venous and arterial pressure characteristics

Haemodynamic stability of patients during haemodialysis (HD) sessions is of pivotal importance and accurate determination of dry weight remains a challenge. Little information is available about central venous and aortic pressure during dialysis. In this pilot study we used a non‐invasive technique to describe the changes in central venous pressure (CVP) during dialysis.

Small dense low density lipoprotein particles are associated with poor outcome after angioplasty in peripheral artery disease.

Purpose In patients suffering from symptomatic peripheral artery disease (PAD), percutaneous revascularization is the treatment of choice. However, restenosis may occur in 10 to 60% in the first year depending on a variety of factors. Small dense low density lipoprotein (sdLDL) particles are associated with an increased risk for cardiovascular events, but their role in the process of restenosis is not known. We conducted a prospective study to analyze the association of sdLDL particles with the outcome of balloon angioplasty in PAD. The composite primary endpoint was defined as improved walking distance and absence of restenosis. Methods Patients with angiographically documented PAD of the lower extremities who were scheduled for lower limb revascularization were consecutively recruited for the study. At baseline and at three month follow-up triglyceride, total cholesterol, LDL size and subclasses and HDL cholesterol and ankle-brachial index (ABI) were measured. Three months after the intervention duplex sonography was performed to detect restenosis. Results Sixty-four patients (53% male) with a mean age of 68.6±9.9 years were included. The proportion of small- dense LDL particles (class III and IV) was significantly lower (33.1±11.0% vs. 39.4±12.1%, p = 0.038) in patients who reached the primary end-point compared with those who did not. Patients with improved walking distance and without restenosis had a significantly higher LDL size at baseline (26.6±1.1 nm vs. 26.1±1.1 nm, p = 0.046) and at follow-up (26.7±1.1 nm vs. 26.2±0.9 nm, p = 0.044) than patients without improvement. Conclusions Small-dense LDL particles are associated with worse early outcome in patients undergoing percutaneous revascularization for symptomatic PAD.