SLR - November 2009 - Hilda J. Aviles-Vargas
Reference:
Bishara, R.A., Taha, W., Akladious, I., Allam, M.A. (2009). Ankle Peak Systolic Velocity: New Parameter to Predict Non-healing in Diabetic Foot Lesions. Vascular, 17(5), 264-268.
Scientific Literature Reviews
Reviewed by: Hilda J. Aviles-Vargas, DPM
Residency Program: Yale New Haven/ DVA Healthcare system
Podiatric Relevance:
This is a relevant article to our specialty because it provides us with a new factor to consider while assessing the degree of peripheral ischemia in non-healing diabetic wound.
Methods:
This was a prospective study performed from September 2005 until July 2007, 62 patients were included in the study with a total of a 100 limbs. The study included diabetic patients who had absent dorsalis pedis and posterior tibial pulses in the affected leg, and had foot lesions consisting of ulcers, gangrene, or tissue necrosis. If the patient presented initially with a non-healing foot lesion and required revascularization, the patient was entered once initially for the non-healing lesion and then entered once again after revascularization. If the inclusion criteria were applicable to both limbs in the same patient, each limb was entered separately. Patient data were collected regarding age, gender, diabetes mellitus, hypertension, ischemic heart disease, renal impairment, cerebrovascular accident, dyslypidemia, foot lesions, dorsalis pedis and posterior tibial pulses, and full details of duplex scanning, including ankle peak systolic velocity. Non-ischemic lesions and lesions in revascularized limbs were treated by a standardized daily wound dressing protocol and followed monthly. Non-healing lesions or patients with critical limb ischemia manifestations underwent revascularization procedures by endovascular or open surgical technique. Patients were followed until they reached one of the end points of the study: a healed wound, a healing wound, revascularization procedure, major amputation, or death. Treating physicians were blinded to the results of the Ankle Peak Systolic Velocity. Dupplex scanning was performed by one experienced operator. All patients were rested 1 hour before the scanning and were examined in the supine position. Recordings were made with the room temperature adjusted to 22 degrees Celsius. Peak systolic velocities of the distal posterior tibial artery at or below the malleolar level and the distal anterior tibial artery just above the ankle joint level were recorded. Peak systolic velocities were averaged over three cardiac cycles. If a focal stenotic lesion was detected in one of the distal tibial arteries, velocity measurements were taken distal to the stenosis. Statistical analysis was performed including a receiver operating characteristic curve, which was used to determine the cutoff ankle peak systolic velocity value with the maximum sensitivity and specificity. A p ≤ .05 was considered statistically significant.
Results:
43 limbs with diabetic foot lesions reach the end point of adequate healing or complete healing: 7 without revascularization and 36 following revascularization. 57 limbs with diabetic foot lesions had non-healing wounds or showed critical limb ischemia manifestations: 48 had revascularization procedures, 2 had primary amputations, 2 had major amputations after a failed revascularization, 1 patient died, and 4 were non-compliant and lost to follow-up. The median ankle peak systolic velocity of the 43 limbs that reached adequate or complete healing was significantly higher than the 57 limbs with non-healing lesion: 53cm/s versus 19.2 cm/s, p <. .0001. To identify independent predictors of wound healing a logistic regression analysis was performed and all variables except ankle peak systolic velocity were non-significant in predicting healing versus non-healing. At a cutoff value of 35 cm/s, the ankle peak systolic velocity showed 92.9% sensitivity, 90.6% specificity, a positive predictive value of 92.9%, and a negative predictive value of 90.6%. A subgroup of 30 patients had the ankle peak systolic velocity assessed before and after revascularization and a significant difference was found between the ankle peak systolic velocity before and after revascularization: 20.4 cm/s versus 48.8 cm/s, p < .0001. There was no significant difference between the ankle peak systolic velocity of the limbs that underwent open surgery versus endovascular revascularization.
Conclusions:
According to this study results, it would be appropriate to use the ankle peak systolic volume parameter to predict the non-healing potential of a diabetic foot lesions. If foot perfusion is significantly impaired as indicated by a low ankle peak systolic velocity, healing is unlikely. On the other hand, if foot perfusion is adequate, as indicated by a high ankle peak systolic velocity, wound healing may or may not be achieved due to other contributing factors that may impair healing.