Takahiro Toyofuku

Quantitative evaluation of the outcomes of revascularization procedures for peripheral arterial disease using indocyanine green angiography.

OBJECTIVES We performed indocyanine green angiography (ICGA) in patients with peripheral arterial disease (PAD), and established a method for the quantitative measurement of appropriate parameters to assess peripheral perfusion and the applicability of ICGA tests. METHODS Twenty-one patients with PAD underwent revascularization procedures with pre- and postinterventional ICGA tests. The ICGA parameters, which included the magnitude of intensity of indocyanine green, the time to maximum intensity, and the time from fluorescence onset to half the maximum intensity (T1/2) were compared with the ankle-brachial pressure index, toe -brachial pressure index, and toe pressure. We evaluated these parameters for regions of interest (ROIs). RESULTS T1/2 was the strongest parameter among all parameters of the ICGA tests. ROI 3, which included the distal region of the first metatarsal bone, correlated more significantly with the traditional measurements than the other ROIs. A value of T1/2 >20 seconds for ROI 3 was significantly correlated with a toe pressure of <50 mmHg (sensitivity: 0.77, specificity: 0.80). CONCLUSIONS ICGA can be used to assess peripheral tissue perfusion. By measuring the value of T1/2 in ROI 3, ICGA tests can be used to evaluate the outcomes of revascularization procedures.

Differential detection rate of periodontopathic bacteria in atherosclerosis

PurposePeriodontitis has been associated with atherosclerotic cardiovascular lesions. There may be a link between periodontopathic bacterial infection and atherosclerosis.MethodsIn 53 patients with atherosclerosis, periodontal disease was classified according to the probing depth of the periodontal pocket. To compare the detection rate in different arterial lesion, specimens of diseased arteries (10 primary atherosclerotic lesions, 43 anastomotic lesions) and 21 control arteries without atherosclerotic findings macroscopically and microscopically in the arterial wall, obtained during the surgical procedures were examined for the presence of five species of putative periodontal bacteria using polymerase chain reaction (PCR) analysis.ResultsFifty-one of the 53 patients (96%) had periodontitis, and 34 (64%) of those patients had severe periodontitis or were edentulous. In total, PCR analysis detected DNA specific for periodontal bacteria in 28 of the 53 specimens (52%) of atherosclerotic arterial wall. Only 5 of 21 (23%) were detected in control specimens.ConclusionsA high percentage of periodontopathic bacteria were detected in atherosclerotic arterial wall specimens from patients with atherosclerosis, especially with primary atherosclerotic lesions, and most cases had severe periodontitis.

Surgical thrombectomy and simultaneous stenting for deep venous thrombosis caused by iliac vein compression syndrome (May-Thurner syndrome).

PURPOSE Iliac vein compression syndrome (May-Thurner syndrome) is characterized by left iliac vein obstruction secondary to compression by the right common iliac artery against the fifth-lumbar vertebra, which increases incidence of deep venous thrombosis (DVT). We treated the patients with DVT due to May-Thurner syndrome (MTS) by surgical thrombectomy and simultaneous stenting, and this study is to evaluate the outcomes of this procedure. METHODS From January 2009 to December 2011, a total of 8 patients underwent surgical thrombectomy with stenting. All patients were admitted for acute DVT involving the left iliofemoral segment, and diagnosed MTS. Patients were followed-up, and stent patency was assessed by means of duplex sonography. RESULTS In all patients, the procedure was successful in achieving re-canalisation of the iliofemoral veins at the end of the operation. Perioperatively, there was no mortality and there was no case of clinically detected pulmonary embolism. Rethrombosis occurred within seven days of operation in 2 patients. During the follow-up period (mean; 16 months), 6 of 8 patients kept patent stents. CONCLUSION Venous thrombectomy with simultaneous stenting is a potent technique to treat acute iliofemoral DVT due to MTS. This technique can restore venous patency and provide relief of the acute symptoms.

Intraarterial Injection of Indocyanine Green for Evaluation of Peripheral Blood Circulation in Patients with Peripheral Arterial Disease

BACKGROUND To assess the peripheral blood flow of patients with peripheral arterial disease (PAD) by indocyanine green (ICG) arteriography (ICGA) with intraarterial injection of ICG and evaluate the efficacy of the ICGA tests. METHODS This study was undertaken from a retrospective review of patients with PAD who underwent ICGA tests during digital subtraction angiography (DSA) between November 2012 and June 2013. We defined some ICGA parameters as the magnitude of intensity of ICG, the time to maximum intensity, and the time from fluorescence onset to half the maximum intensity (T1/2). The ICGA parameters were evaluated in 2 regions, named regions of interest (ROIs). ROI 1 was part of the dorsum of the foot from the Chopart joint to the Lisfranc joint. ROI 2 was in the distal region of the first metatarsal bone and compared with the ankle-brachial pressure index (ABI), ankle pressure, toe-brachial pressure index, and toe pressure. RESULTS A total of 22 limbs in 16 patients with PAD underwent ICGA tests during DSA. The T1/2 on ROI 2 was the most correlated with the ABI (ρ=-0.622, P=0.003). A value of T1/2 for ROI 2>10 sec was significantly correlated with an ABI value of <0.7 (sensitivity: 0.85, specificity: 1.0). CONCLUSIONS By measuring the value of T1/2 in ROI 2, ICGA tests can be performed to assess the peripheral blood circulation during DSA. ICGA tests might help to promptly assess the peripheral blood flow during endovascular treatment procedures.

Indocyanine Green Angiography for the Diagnosis of Peripheral Arterial Disease with Isolated Infrapopliteal Lesions

BACKGROUND In this study, we evaluated the accuracy of the indocyanine green angiography (ICGA) test to diagnose peripheral arterial disease (PAD) with isolated infrapopliteal lesions. METHODS This study was undertaken from a retrospective review of PAD patients with isolated infrapopliteal lesions who underwent ICGA between November 2012 and July 2013. We calculated the ICGA parameters while comparing the findings with the ankle-brachial index (ABI) and toe-brachial index (TBI) in patients with infrapopliteal lesions. RESULTS Twenty-three limbs with isolated infrapopliteal lesions in 14 PAD patients and 15 limbs without arterial lesions in 9 control patients were examined using ABI, TBI, and ICGA. The Td 90% (the time elapsed from the maximum intensity to 90% of the maximum intensity) correlated most significantly with the ABI value. A cutoff value of Td 90% >25 sec also significantly correlated with the presence of PAD (sensitivity, 82.6%). CONCLUSIONS ICGA might therefore be useful for assessing the peripheral perfusion quantitatively, even in PAD patients with isolated infrapopliteal lesions. The use of Td 90% on ICGA may also be effective for accurately estimating the presence of PAD.

Polymyxin B-immobilized fiber column hemoperfusion removes endotoxin throughout a 24-hour treatment period

PURPOSE The purpose of this study was to evaluate the extent of endotoxin adsorption by polymyxin B-immobilized fiber column hemoperfusion (PMX) performed for a 24-hour treatment period in patients with septic shock. MATERIALS AND METHODS Nineteen patients with septic shock were retrospectively studied. The plasma endotoxin concentrations of blood drawn from the radial artery and from the outlet circuit of the PMX column were measured by kinetic turbidimetric limulus assay using an MT-358 Toxinometer (Wako Pure Chemical Industries, Ltd, Osaka, Japan) after 24 hours of PMX treatment. The endotoxin removal rate was defined by the following equation: ([radial artery endotoxin concentration - outlet circuit of PMX column endotoxin concentration]/radial artery endotoxin concentration) × 100%. RESULTS The patients had a median Acute Physiology and Chronic Health Evaluation II score of 29 at intensive care unit admission and a 28-day mortality of 47%. Before the start of the PMX treatment, the median radial arterial plasma endotoxin concentration was 16.48 pg/mL. After 24 hours of PMX treatment, the median radial plasma endotoxin concentration had decreased to 1.857 pg/mL, and the concentration at the outlet circuit of the PMX column was further decreased to 0.779 pg/mL. The median endotoxin removal rate was 74.4%. CONCLUSION These findings suggest that 24-hour PMX treatment was effective in removing endotoxin continuously throughout the entire treatment period.

Association between periodontitis and the development of systemic diseases

Periodontal diseases, common infectious diseases seen in humans, are characterized by gingival inflammation and a loss of connective tissue and bone around the roots of teeth, which leads to eventual tooth exfoliation. In the past decade, the association between periodontal diseases and the development of systemic diseases has received increasing attention. Periodontal pathogens and their products, as well as inflammatory mediators produced in periodontal tissues, can enter the bloodstream, thereby causing and/ or contributing to the development of systemic diseases. A variety of recent studies have compiled various results showing that periodontal infections are implicated in the development of various systemic diseases. This review summarizes the evolution of the focal infection theory to the current understanding of the pathophysiology of periodontal disease and presents an update of the mechanisms and relationships between chronic periodontitis and systemic diseases, including cardiovascular diseases, respiratory infections, preterm delivery of low-birth-weight fetuses and diabetes mellitus.

Quantitative evaluation of microvascular dysfunction in peripheral neuropathy with diabetes by indocyanine green angiography

AIMS Peripheral neuropathy in diabetes (PND) plays a central role in foot ulceration with diabetes, and leads to an abnormal microvascular structure, including arteriovenous shunting. To assess the extent of arteriovenous shunting we performed indocyanine green angiography (ICGA) in patients with diabetes and evaluated quantitative ICGA parameters. METHODS Between November 2012 and July 2013, twenty-six limbs in 14 patients with PND and twenty-three limbs in 15 patients without PND underwent ICGA testing. The ICGA parameters, which included the time to maximum intensity (Tmax), the time from fluorescence onset to half the maximum intensity (T1/2), the time elapsed from the maximum intensity to 90% of the Imax and to 75% of the Imax (Td 90% and Td 75%, respectively) and the rate of intensity measured 60s after the Tmax to Imax (IR 60s), were compared between the patients with and without PND. RESULTS The Tmax, T1/2, Td 90%, Td 75% and IR 60s were significantly different between patients with and without PND. A value of Td 90% >30s was significantly correlated with the presence of PND (sensitivity: 0.85, specificity: 0.78). CONCLUSIONS ICGA tests can be used to quantitatively assess arteriovenous shunting in the limbs with PND. By measuring the value of the Td 90%, ICGA tests can estimate the presence of the arterio-venous shunting in PND, which might be helpful for assessing the progression of foot ulceration with diabetes, gangrene and the need for amputation.

Combined arterial reconstruction and free tissue transfer for patients with critical limb ischemia.

OBJECTIVE The purpose of treatment for critical limb ischemia (CLI) is to prevent major amputation. The purpose of this study was to evaluate our experience of treating CLI with free tissue transfer (FTT) and revascularization. MATERIALS AND METHODS From January 2010 to December 2012, seven lower extremities in seven patients were treated with revascularization and free tissue transfer for CLI with tissue loss. All seven patients had tissue loss with a Rutherford category 6 status. Six patients underwent bypass surgery, and one patient underwent percutaneous transluminal angioplasty for revascularization. All patients also underwent free tissue transfer using the latissimus dorsi muscle simultaneously and separately in two and five patients, respectively. RESULTS Five of the seven patients exhibited flap patency and survival. One patient obtained flap survival and limb salvage, although the flap graft was occluded after the patient achieved limb salvage. One patient developed partial flap necrosis requiring skin grafting and acquired limb salvage. The flap survival rate was 85%, and the limb salvage rate was 100%. CONCLUSION FTT with arterial reconstruction for CLI achieves successful wound healing and limb salvage. Both bypass surgery and endovascular treatment are useful for maintaining the vascular supply.

Maggot Debridement Therapy for Peripheral Arterial Disease

INTRODUCTION Maggots are potent debriding agents capable of removing necrotic tissue and slough; however, it is still unclear which wounds are most likely to benefit from maggot debridement therapy (MDT). Thus, we performed this retrospective review to gain insight into the patient and therapy characteristics influencing outcome. PATIENTS AND METHODS We reviewed patients with foot ulcers caused by critical limb ischemia, encountered during the period between June 2005 and May 2010. The treatment outcomes were defined as effective or ineffective. RESULTS There were 16 patients with 16 leg ulcers. The patients were 13 men and 3 women, with an average age of 67.2 years (range, 47-85 years). Ten (63%) of the 16 ulcers were treated effectively. According to univariate analyses, an ankle brachial pressure index (ABI) lower than 0.6 (p = 0.03) had a negative impact on the outcome of MDT; however, outcome was not influenced by gender, obesity, ischemic heart disease, diabetes mellitus, hemodialysis, smoking, or laboratory findings. CONCLUSIONS Some patient characteristics, such as gender, obesity, ischemic heart disease, diabetes mellitus, hemodialysis, and smoking, do not seem to contraindicate eligibility for MDT. However, a limb with an ABI lower than 0.6 is less likely to benefit. (English Translation of J Jpn Coll Angiol 2011; 51: 209-213.).