This article describes the technique of measuring ambulatory venous pressures and their value in the diagnosis and assessment of the severity of venous hypertension as well as their contribution toward our understanding of venous hemodynamics and the pathophysiology of venous disorders. It demonstrates that ambulatory venous pressures are not only of diagnostic significance, but also of prognostic significance. Competent popliteal valves will protect the leg from venous hypertension despite proximal (iliofemoral) occlusion. Although the measurement of ambulatory venous pressures is the “gold standard,” it is invasive and cannot be repeated frequently nor can it be used as a screening test. It has been employed in the validation of a number of noninvasive tests now used for the routine screening of patients. Nevertheless, ambulatory venous pressure measurements are essential if the beneficial hemodynamic effect of surgical reconstructive procedures is to be convincingly demonstrated.

Superficial vein thrombosis is characterized by clotting of superficial veins (ie, following direct trauma) with minimal inflammatory components. Superficial thrombophlebitis is a minimally thrombotic process of superficial veins associated with inflammatory changes and/or infection. Treatments generally include analgesics, elastic compression, anti-inflammatory agents, exercise and ambulation, and, in some cases, local or systemic anticoagulants. It is better to avoid bed rest and reduced mobility. Topical analgesia with nonsteroidal, anti-inflammatory creams applied locally to the superficial vein thrombosis/superficial thrombophlebitis area controls symptoms. Hirudoid cream (heparinoid) shortens the duration of signs/symptoms. Locally acting anticoagulants/antithrombotics (Viatromb, Lipohep, spray Na-heparin) have positive effects on pain and on the reduction in thrombus size. Intravenous catheters should be changed every 24 to 48 hours (depending on venous flow and clinical parameters) to prevent superficial vein thrombosis/superficial thrombophlebitis and removed in case of events. Low molecular weight heparin prophylaxis and nitroglycerin patches distal to peripheral lines may reduce the incidence of superficial vein thrombosis/superficial thrombophlebitis in patients with vein catheters. In case of superficial vein thrombosis/superficial thrombophlebitis, vein lines should be removed. In neoplastic diseases and hematological disorders, anticoagulants may be necessary. Exercise reduces pain and the possibility of deep vein thrombosis. Only in cases in which pain is very severe is bed rest necessary. Deep vein thrombosis prophylaxis should be established in patients with reduced mobility. Antibiotics usually do not have a place in superficial vein thrombosis/superficial thrombophlebitis unless there are documented infections. Prevention of superficial vein thrombosis should be considered on the basis of patient's history and clinical evaluation.

A total of 149 consecutive unselected patients (221 limbs) who presented with signs and symptoms of chronic venous problems (varicose veins with or without ankle oedema, skin changes and leg ulcers) have been studied by clinical examination, ascending deep to superficial venography, Doppler ultrasound and ambulatory venous pressure measurements. Of the limbs, 180 (82 per cent) had varicose veins without obstruction in the deep veins or reflux in the popliteal or femoral veins while 41 (18 per cent) had deep venous disease. Of the 180 limbs with 'primary' varicose veins 110 (60 per cent) did not have incompetent calf perforating veins (group A) while 70 (40 per cent) did (group B). On the basis of the ambulatory venous pressure after calf muscle exercise and the refilling time, the incompetent calf perforating veins of limbs in group B belonged to three subgroups of different haemodynamic significance. In 20 limbs (30 per cent) they were found to be of no haemodynamic significance, in 25 (35 per cent) of moderate haemodynamic significance and in 25 (35 per cent) of major haemodynamic significance. The last were, on clinical examination, indistinguishable from limbs with deep venous disease although they had patent deep veins with competent popliteal valves.

The purpose of the study was to determine the association between cerebral infarction seen on CT scan and macroscopic ulceration of atheromatous carotid plaques in patients undergoing carotid endarterectomy. Following carotid endarterectomy in 65 patients, specimens were examined for the presence of ulceration without knowing the result of the preoperative CT brain scan. The 65 patients thus investigated underwent 68 carotid endarterectomies: 36 for a history of transient ischemic attacks (TIAs), 13 for amaurosis fugax, and six for prior strokes; 13 asymptomatic patients had prophylactic carotid endarterectomy prior to coronary bypass. A macroscopic ulcer was present in 42 specimens. Twenty-six (62%) of the patients with ulceration had one or more ipsilateral cerebral infarcts on CT scan. Only two (8%) of the 26 patients without an ulcer had cerebral infarcts. Of the 36 patients who presented with TIAs, 26 (72%) had carotid plaque ulcers and 23 (88%) of these had cerebral infarcts on CT scan also. In contrast, only three of 13 asymptomatic patients had plaque ulcers and only one of these had a cerebral infarct. There is a high incidence of cerebral infarction seen on CT scan in patients presenting with TIAs. These infarcts occur predominantly in patients with ulcerated atheromatous carotid lesions.

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