Chumpol Wongwanit

Optimization of the table speed of lower extremity CT angiography protocols in different patient age groups

BACKGROUND Scanning with 64-slice multidetector row CT (MDCT) is usually faster than blood flow in peripheral arteries of the lower extremities, and the distal arteries of lower extremities are difficult to visualize, particularly in elderly patients. Thus, the optimal table speed for CT angiography (CTA) studies should be adjusted for appropriate patient age groups. OBJECTIVE We evaluated the relative efficacy of different table speeds in several age groups of patients with suspected peripheral arterial occlusive disease (PAOD) undergoing CTA of lower extremity arteries, as a guideline for routine use. METHODS This retrospective study reviewed routine CTA of the lower extremity arteries of 107 patients with suspected PAOD to evaluate vascular opacification in each vascular segment of 5 age groups: < or =40 years (group 1), 41-60 years (group 2), 61-70 years (group 3), 71-75 years (group 4), and > or =76 years (group 5). Adequate vascular opacification was measured for attenuation in the suprarenal and infrarenal abdominal aorta and in the arteries of the lower extremity. Venous contamination was also measured. RESULTS Adequate vascular opacification from the suprarenal aorta to the level of the mid-popliteal artery was shown in all patients. Arterial opacification at the dorsalis pedis or plantar arteries was visualized in 85.7%-91.7% of patients and at the plantar arch arteries in 84.1%-91.7%. Minimal venous contamination was also shown adjacent to arterial enhancement, ranging from 0% to 28.6%. CONCLUSION Performing CTA of the lower extremities with 64-slice MDCT could reduce the table speed to allow adequate arterial opacification and minimal venous contamination.

Pedal bypass with deep venous arterialization: the therapeutic option in critical limb ischemia and unreconstructable distal arteries.

Heavily calcified and severely stenotic distal arteries defined as unreconstructable, precludes the possibility of revascularization, resulting in major amputation in patients with critical limb ischemia. However, providing blood supply to the ischemic foot through the venous system instead of the arterial system may improve the circulation adequately for the healing process in the vascular compromised distal tissue. This study aimed to assess the safety and efficacy of pedal bypass with deep venous arterialization, one of the possible procedures to improve the circulation through the venous system in critically ischemic limbs and unreconstructable distal arteries. Twenty-six patients with critical limb ischemia and an unreconstructable distal artery of the lower extremities were included for the surgical procedure. Arterial bypass with distal anastomosis at the paramalleolar deep vein was carried out through a composite graft combined with adequate destruction of valve competency in the distal vein. The primary endpoint was complete healing of ischemic ulcer with amelioration of rest pain within six months. The secondary endpoints were the outcomes of survival, limb salvage and primary graft patency rate at six-month intervals to 24 months. Nineteen patients (73.1%) had complete healing of ischemic ulcer and disappearance of rest pain within six months. Six patients (23.1%) underwent major amputation. Perioperative mortality was 3.8%. After 24 months of follow-up study, the survival rate was 87.5%, whereas the limb salvage and graft patency rates were 76.02 and 49.17%, respectively. Pedal bypass with deep venous arterialization may be another therapeutic option to enhance the healing of ischemic ulcer and limb salvageability in patients with critical limb ischemia and unreconstructable distal artery.

Endovenous radiofrequency thermal ablation and ultrasound-guided foam sclerotherapy in treatment of klippel-trenaunay syndrome.

INTRODUCTION Klippel-Trenaunay syndrome is composed of port-wine stain, limb hypertrophy and varicose veins. METHODS The two patients with Klippel-Trenaunay syndrome treated by endovenous radiofrequency thermal ablation and ultrasound-guided foam sclerotherapy of the abnormal veins was conducted. RESULTS Radiofrequency thermal ablation resulted in successful occlusion of the incompetent anterior accessory great saphenous vein. Moreover, ultrasound-guided foam sclerotherapy showed complete occlusion of the residual veins. At 6 month follow-up, both patients markedly decreased leg symptoms including pain, cramping, limb swelling, and bulging of veins. CONCLUSION Radiofrequency thermal ablation combined with foam sclerotherapy is a minimally invasive procedure alternative to the standard invasive surgery and can be the option for saphenous ablation in Klippel-Trenaunay syndrome patients.

Comparison of clinical prediction scores for the diagnosis of deep vein thrombosis in unselected population of outpatients and inpatients

Objectives The aim of this research was to compare the accuracy of the modified Wells, the Wells, the Kahn, the St. André, and the Constans score for the diagnosis of deep vein thrombosis of the lower limb in unselected population of outpatients and inpatients. Method The pretest of probability score was employed in consecutive 500 outpatients and inpatients with suspicion of deep vein thrombosis. All patients were examined with compression ultrasonography. Results Deep vein thrombosis was confirmed in 26.4%. In the unselected population of outpatients and inpatients, the accuracy of the modified Wells score and the Constans score was higher than other scores. Both scores were more accurate for the outpatients. There was no accurate score for the inpatient subgroup. Conclusions The modified Wells and the Constans score appear to be useful in the unselected population of outpatients and inpatients and particularly in the outpatient subgroup.

Use of customised pressure‐guided elastic bandages to improve efficacy of compression bandaging for venous ulcers

Compression bandaging is a major treatment of chronic venous ulcers. Its efficacy depends on the applied pressure, which is dependent on the skill of the individual applying the bandage. To improve the quality of bandaging by reducing the variability in compression bandage interface pressures, we changed elastic bandages into a customised version by marking them with circular ink stamps, applied when the stretch achieves an interface pressure between 35 and 45 mmHg. Repeated applications by 20 residents of the customised bandage and non‐marked bandage to one smaller and one larger leg were evaluated by measuring the sub‐bandage pressure.

A new pretest probability score for diagnosis of lower limb deep vein thrombosis in unselected population of outpatients and inpatients

Objective To develop a new pretest probability score for deep vein thrombosis (DVT) in unselected population of outpatients and inpatients. Methods The new score was developed using independent factors from 500 patients clinically suspected of leg DVT. The new score was validated in a second group of 315 patients. Results The score consists of four components: unilateral leg pain, confinement to bed, calf enlargement >3 cm compared with the other side, and previous venous thromboembolism. A score ≥2 indicated a high probability while a score <2 indicated low probability. The sensitivity and specificity of the new score were 71.60% and 79.49%, respectively. The area under the receiver operating characteristic curve for the new score was 0.79. The combination of a new score <2 and D-dimer level <500 µg/L had a negative predictive value of 96.43%. Conclusions Our new score was valid in an unselected population of outpatients and inpatients.

Comparative Study of the Management of Diabetic versus Nondiabetic Patients with Atherosclerosis Obliterans of the Lower Extremities

The aim of this study was to identify the influence of diabetes mellitus on patients with atherosclerosis obliterans (ASO) of the lower extremities. A prospective study was designed to compare differences between ASO patients with and without diabetes mellitus in regard to clinical characteristics and outcomes of management. Two hundred fifty-three consecutive (61.1%) diabetic and 161 (38.9%) nondiabetic patients were included in this study. Crural artery occlusion occurred more frequently in diabetic patients (tibioperoneal segment 26.5% vs 14.3%; p = .003). Diabetic patients had higher comorbidities, such as ischemic heart disease, disabling stroke, and renal failure. Infection requiring urgent surgical intervention was higher in diabetic patients (39.1% vs 24.2%; p = .001). This required primary major amputation in limb-threatening ischemia superimposed with infection (27.6% vs 17.7%; p = .037). The feasibility (67.2% vs 69.8%; p = .651) and success (74.4% vs 79.0%; p = .481) of revascularization between the two groups were comparable. Diabetic patients often needed more distal revascularization for limb salvage (34.4% vs 18.5%; p = .019). The mortality rate after revascularization was higher in diabetic patients (13.3% vs 2.5%; p = .009). Diabetes mellitus per se has no direct impact on limb salvageability in limb-threatening ischemia. The parity of feasibility and success in revascularization between the two groups should encourage attempts at limb salvage revascularization in diabetic patients.

Customizing elastic pressure bandages for reuse to a predetermined, sub-bandage pressure: A randomized controlled trial

Objective A randomized clinical trial was performed to compare the effectiveness of unmarked bandages and customized bandages with visual markers in reproducing the desired sub-bandage pressure during self-bandaging by patients. Method Ninety patients were randomly allocated to two groups (“customized bandages” and “unmarked bandages”) and asked to perform self-bandaging three times. The achievement of a pressure between 35 and 45 mmHg in at least two of the three attempts was defined as adequate quality. Results Adequate quality was achieved by 33.0% when applying the unmarked bandages, and 60.0% when applying the customized bandages (p = 0.02). Use of the customized bandage and previous experience of bandaging were independent predictors for the achievement of the predetermined sub-bandage pressure (p = 0.005 and p = 0.021, respectively). Conclusion Customized bandages may achieve predetermined sub-bandage pressures more closely than standard, unmarked, compression bandages. Clinical trials registration ClinicalTrials.gov (NCT02729688). Effectiveness of a Pressure Indicator Guided and a Conventional Bandaging in Treatment of Venous Leg Ulcer. https://clinicaltrials.gov/ct2/show/NCT02729688

FT09. Factors Influencing Favorable Outcome and Persistent Infection of Endovascular Aneurysm Repair for Infected Abdominal Aortic Aneurysm

underwent in situ aortic reconstructions (48% abdominal aortic, 52% aortoiliac) using CAAs for infective aortic aneurysm (n 1⁄4 25 [66%]) and aortic prosthesis infection (n 1⁄4 13 [34%]). Among them, four (10.5%) patients presented with aortoenteric fistula. There were four (10.5%) early (<30 days) and seven (18%) late postoperative deaths during the follow-up period (median, 13.6 months; range, 1-72 months). Early mortality was attributed to CAA rupture, whereas late mortality was not related to an aorta-related cause. Four (10.5%) GRCs developed during the follow-up period; these included thrombotic iliac limb occlusion (n 1⁄4 1), aneurysmal dilation of CAA (n1⁄4 1), aortoenteric fistula (n 1⁄4 1) after fall down injury, and graft rupture (n 1⁄4 1). Patient survival and event-free survival rates at 3 years were 77% and 64%, respectively. Conclusions: In situ abdominal aortic reconstruction with CAA showed good results for patients with primary or secondary aortic infection even in immunocompromised patients. Although aorta-related mortality usually developed in the early postoperative period, postoperative surveillance of CAA is recommended to detect GRCs.

Risk factors for endovenous heat-induced thrombosis after endovenous radiofrequency ablation performed in Thailand

Objective We aimed to determine the incidence of and associated risk factors for endovenous heat-induced thrombosis (EHIT) after endovenous radiofrequency ablation (RFA). Methods We retrospectively reviewed the medical records of 82 patients with 97 great saphenous veins undergoing RFA from 2012 to 2014. Results The incidence of EHIT was 10.3%. Class 1, 2, and 3 EHIT was found in 50%, 30%, and 20% of legs, respectively. No class 4 EHIT, deep vein thrombosis, or pulmonary emboli occurred. Univariate analysis revealed that the associated risk factors for EHIT were a vein diameter of >10 mm, operative time of >40 min, and Caprini score of >6. Multivariate analysis revealed that the independent risk factors associated with EHIT were a vein diameter of >10 mm and operative time of >40 min. Conclusions A vein diameter of >10 mm and operative time of >40 min might be predictive factors for EHIT following RFA.