Vein size and demographics: is there a correlation?
Peripheral arterial occlusive disease has a high prevalence worldwide, as well as in our population, and contributes to an immense burden of morbidity and mortality. Due to the systemic nature of especially atherosclerotic vascular disease, most patients also have cardiovascular and cerebrovascular involvement at the time of presentation, adding to the huge impact on the patient and the economy. Lower limb amputation is associated with a 50% 5-year mortality rate, thus peripheral arterial disease itself is also responsible for considerable mortality rates. Attempting to re-establish perfusion to an ischaemic limb is crucial in saving the limb and the life of the patient. Options for revascularisation of patients with limb-threatening ischaemia include open and endovascular approaches, each with its own indications and shortcomings. In the case of open infra-inguinal bypass grafting, the great saphenous vein is the preferred conduit used to replace the diseased segment. It has been proven to perform superiorly to synthetic grafts with respect to long-term patency, adequate length, and swift harvesting. This vein is also used in other autogenous bypass procedures, including coronary bypass graft surgery and arterio-venous fistula grafts for access in renal replacement therapy. Occlusion of the graft, or graft-failure, is one of the dreaded complications of any bypass procedure, and can be divided into primary or secondary failure, according to the time from procedure to the establishment of the diagnosis. Both scenarios are detrimental to the salvage rate of the limb, and can also indirectly contribute to the demise of the patient. Many factors have been associated with primary graft failure, particularly the size of the conduit graft, which was the main focus of our study. Our primary aim was to determine the average great saphenous vein size in our study population, and our secondary aim was to demonstrate a relationship between vein size and demographic variables like race, age and gender. The study was a cross-sectional retrospective study, using data over 10 years from January 2006 to December 2015. All patients underwent vein mapping with ultrasound pre-operatively prior to a lower limb bypass procedure in Universitas Academic Hospital, and the demographics of these patients were then analysed. A total of 811 patients were included and the meteorological season was used as a surrogate indication of the average temperature in the vascular suite to account for the influence of ambient temperature on vaso-action and vein size. The average size of the great saphenous vein in our study population was found to be 4.08 mm. After analysis, it was found that black patients had smaller veins than white patients (p < 0.0001) and men had smaller veins than women (p = 0.0217). Vein measurements were smaller during summer months, and there was no significant difference between vein sizes in different age groups. Owing to the existing risk of small conduit size for graft failure, vein size plays an important role in the choice of procedure used to revascularize limbs in patients with critical ischaemia, whether acute or chronic. The results from our study may assist in improving selection of patients suitable for open surgery based on demographic parameters, thus decreasing poor outcomes of revascularisation procedures and decreasing complications associated with graft failure.