The proceed subject with two purposes: Study on clinical characteristics of lower extemity arterial disease with infrapopliteal lesions. Evaluate mid-term outcomes and factors influencing clinical outcomes of infrapopliteal angioplasty in patient with lower extremity arterial disease.
MINISTRY OF EDUCATION AND TRAINING MINISTRY OF DEFENCE 108 INSTITUTE OF CLINICAL MEDICAL AND PHARMACEUTICAL SCIENCES LUONG TUAN ANH THE CLINICAL CHARACTERISTICS ANDEFFICACY OFINFRAPOPLITEAL PERCUTANEOUS TRANSLUMINAL ANGIOPLASTY IN PATIENT WITH LOWER EXTREMITY ARTERIAL DISEASE Speciality: Cardiology Code: 62.72.01.41 ABSTRACT OF MEDICAL PHD THESIS Hanoi – 2019 THE THESIS WAS DONE IN:108 INSTITUTE OF CLINICAL MEDICAL AND PHARMACEUTICAL SCIENCES Supervisor: Ass.Prof.PhD Le Van Truong Ass.Prof.PhD Vu Dien Bien Reviewer: This thesis will be presented at Institute Council at:108 Institute of Clinical Medical and Pharmaceutical Sciences Day Month Year 2019 The thesis can be found at: National Library of Vietnam Library of 108 Institute of Clinical Medical and Pharmaceutical Sciences INTRODUCTION Lower extremity arterial disease (LEAD) is very common, prevalence 3-7% of the population, 20% in people over 75 years old Ulcers and gangrenelower limb is the end- stages of the disease, threatened amputation, loss of limb functiondue to infrapopliteal arterial lesions Below the knee revascularizationis the most important in limb salvage for this disease There are two methods of infrapopliteal arterial revascularization: bypass surgery and percutaneous angioplasty, so bypass surgery is difficult due to below the knee artery small, long lesions, bad run-off, elderly patients, many serious diseases combined Percutaneous transluminal angioplasty (PTA)is becoming as important treatments for this area Currently LEAD with infrapopliteal lesions was concerned, innitial step was deployed in Vietnam, yet researchs on medium and long-term effectiveness, small sizes, should we proceed subject with two purposes: Study on clinical characteristics of lower extemity arterial disease with infrapopliteal lesions Evaluate mid-term outcomes and factors influencing clinical outcomes of infrapopliteal angioplasty in patient with lower extremity arterial disease Chapter OVERVIEW 1.1 LEAD Concept Lower extremity arterial disease (LEAD) is only partially or entirely in the lower limbs is not provided with adequate blood, responding to physiological activities, with a duration of time more than two weeks This concept excludes acute limb ischemia, vessel wounds, vascular complications The cause of LEAD is the development of atherosclerotic plaques, which cause a narrowing or complete blockage of the limb vessels Below the knee (BTK) arteriesincludes tibial artery (aterior tibial artery, posterior tibial artery, peroneal artery), pedal artery (dorsal pedal artery, medial plantar artery, lateral plantar artery) 1.2 Clinical Characteristics of LEAD LEAD progresses through several stages, from asymptomatic, claudication, rest pain, ulcer and gangrene Critical limb ischemia (CLI, including rest pain, ulcer and gangrene lower limb) with infrapopliteal arterial lesion, considered the end stage of the LEAD, threaten to limb losss LEAD is a common chronic cardiovascular disease caused by atherosclerosis, with coronary artery disease and stroke, the prevalence of 3-7% of the population (20% in people over 70 years of age), of which the rate of CLI is % population Common risk factors of LEAD are elderly age (> 50 years), smoking, diabetes, hypertension, and dyslipidemia Table 1.2 Rutherford classification of PAD Grade Category Clinical 0 Asymptomatic I Mild claudication I Moderate claudication I Severe claudication II Rest pain III Minor tissue loss IV Major tissue loss 1.3 LEAD Diagnostics Hemodynamic tests Imaging Diagnostics ABI index Doppler and Duplex Ultrasound TBI index CTA Treadmill test MRA Segmental systolic pressure Angiography TcPO2, SPP In which the diagnostics tests are used in Vietnam are measuring ABI index, ultrasound of lower extremities arterial lesions, CTA before percutaneous transluminal angioplasty, and angiography in intervention procedure 1.4 PTA of LEAD with Infrapopliteal lesions 1.4.1 Treatment Purposes + Reduce symptoms of limb ischemia + Limb salvage 1.4.2 Indications + Clinical stage CLI Moderate claudication or severe claudication does not respond to medical treatment + Arterial lesion classification TASC B, C, D (TASC 2000) + Multi-level of lower extremity arterial lesion Aortoiliac lesions: aorto-iliac occlusion, aorto-iliac stenosis in patient when life expectancy is not over years Femoro-popliteal lesions: short lesions (< 25cm), long lesions (≥ 25cm) in patient when life expectancy is not over years 1.4.3 Techniques of infrapopliteal revascularization There are currently two techniques of infrapopliteal revascularization are: balloon angioplasty (plain balloon, drug coated balloon), stenting (covered and uncovered stent), with specified is: + Balloon angioplasty is the priority technique + Stenting if the ballooning is not effective BTK intervention is considered to be a revascularization method with a high effectiveness of limb preservation, less complications than bypass surgery In which, plain ballooning is the priority method, assessing the effectiveness of normal ballooning with different types of infrapopliteal lesions as well as combining with additional techniques (drug-coated balls, atherectomy, ) in order to reduce the rate of restenosis is still needing further research to confirm the effect Chapter SUBJECTS AND METHODS 2.1 RESEARCH SUBJECTS 85 patients with 91 infrapopliteal arterial lesions, were reperfusioned by PTA in 108 hospital from May 2011 to June 2016 2.1.1 Selection criteria - There are clinical symptoms of lower limbs ischemia, duration of time more than weeks - Infrapopliteal arterial stenosis is over 50% diameter or total occlusion (angiography), correspond to clinical symptoms of lower limbs ischemia - Patients agree to participate in the research 2.1.2 Exclusion criteria - Acute limb ischemia (ALI) - Non-atherosclerosis LEAD (Takayasu, Bueger, Raynaud, ) - Infrapopliteal arterial stenosis or occlusion due to external causes of vessel (tumor, trauma, ) - Venous disease of lower limbs (varicose veins, venous thrombosis, ) - Peripheral neuropathy of lower limb (peripheral neuritis, peripheral neuropathy due to diabetes, ) - Severe disease (liver failure, renal failure, heart failure, acute myocardial infarction, stroke, severe infections) 2.2 RESEARCH METHOD 2.2.1 Study design: prospective, intervention, follow-up 2.2.2 Research steps 2.2.2.1 Before lower limb PTA Patients should be screened and tested for investigation eligibility Patients meet inclusion criteria will be asked to participate in this research + Clinical examination: finding limb ischemia, duration of illness, cardiovascular risk factors (old age, diabetes, hypertension, smoking, metabolic lipid disorders, coronary artery disease, stroke, ) +Laboratory tests: - Blood tests: blood formulation, coagulation tests (Prothrombin, INR, APTT, Fibrinogen), blood biochemistry tests (Ure, Creatinine, Lipid, Protid, Albumin, Bilirubin, SGOT, SGPT, electrolytes), immunity tests (HBsAg, anti-HIV, anti-HCV) - Cardiopulmonary X-ray, ECG, echocardiography - ABI index ABI measured by Doppler handheld smartdrop 45 (Japan), from 2011 to 2013, when we did not have automatic ABI meter and by ABI automatic ABI meter VP1000 Plus (OMRON, Japan), from 2013 to 2016 +Lower limb arteries ultrasound by GE Vivid (GE, USA), in cardiology department (108 hospital) +Lower extremity artery imaging byMSCT 16 slices Brivo 385 (GE, USA), in imaging diagnostic department (108 hospital) 2.2.2.2 Lower Limb PTA Iliac artery lesion and femoral artery lesion were revascularized before infrapopliteal artery lesion It will be possible to open lesions in one or two sessions, depending on each patient + Patient preparation: patients being screened, tested and explained deeply about disease and treatment method Patients was asked to sign an informed consent, not eating and drinking at least 6h before procedure + Interventional procedure of iliac and femoral artery occlusion - Anesthesia: local anesthesia with 5-10ml lidocaine 2% in vascular access - Patient posture: lying on the back - Vascular access: common femoral artery or brachial artery - Giving the catheter to the iliac and femoral artery occlusions, taking assessments the lesion, collateral branches and run-off - Going through the occlusion by guidewire 0.035 inches, with intraluminal technique or subintimal technique (in case CTO over months) We could use additional support catheters to increase the ability to pass through the complicated occlusion - Open the occlusion by dilating balloon 6F, 6atm pressure, keeping 30s, then we angiography after deflating balloon.Finishing procedure if the recurrence stenosis under 50% diameter, on the otherwhile choosing the bigger balloon or stenting when balloon failure + Infrapopliteal PTA - Anesthesia: spinal anesthesia at L4-L5 - Patient posture: lying on the back - Vascular access: femoral artery in the side of infrapopliteal lesion - Evaluating the lesions of iliac and femoral artery, collateral circulation and run-off before intervention - Revascularization femoral and popliteal artery occlusion (see above) - Giving guiding catheter to popliteal artery Going through antegrade the infrapopliteal artery lesions by support catheter TrailBlazer 4F (Boston, USA), Controlwire 18 (Boston, USA) When failure, we could go retrograde from tibial artery or pedal artery, with sheath 4F - Dilating the occlusions by balloon 3-3.5 mm diameter for tibial artery and balloon 2-2.5 mm diameter for pedal artery, with 100-200 in length Keeping dilation from 30s to minutes, from to 14 atm pressure - We angiography after deflating balloon Finishing procedure if the recurrence stenosis under 50% diameter, on the otherwhile ballooning again with a more suitable size balloon 2.2.2.3 Follow-up after PTA - Clinical follow-up (FU), re-do all biochemical, hematological after PTA Well treatment for patient until being discharged - Measuring ABI and lower extremity arteries ultrasound after day Amputation gangrene and discharge - Periodic follow-up 1, 3, and 12 months after procedure include clinical examination, ABI measurement, ultrasound, and assessment of 11 Table 3.19.Success rate Success accessment Number of success % Technical success 129 79.6 (n=162*) Hemodynamic success 69 75.8 (n=91) Clinical success 88 96.7 (n=91) Conclusion: Technical success was 79.6% Hemodynamic success was 75.8% Clinical success rate was 96.7% Table 3.22.Wound healing WH monthFU (n=48) WH 3monthsFU (n=47) WH monthsFU (n=46) WH 12 monthsFU (n=46) Number of legs 13 34 46 46 % 27.1 72.3 100 100 Duration of wound healing(month) = 3.1 1.8 Conclusion: Wound healing time was 27.1%, 72.3% and 100% after month, months and months respectively.Mean duration of wound healingwas 3.1 1.8 months Table 3.26.Wound healing and reperfusion WH 1monthFU (2) Yes No WH monthsFU (3) Yes No Reperfusion (1) DR IR (n, %) (n, %) 13 (37.1) (0) 22 13 (62.9) (100) 27 (77.1) (58.3) (22.9) (41.7) p p 1-2 < 0.05 p 1-3 > 0.05 Conclusion: Reperfusion properties (direct/indirect angiosome) affectthe rate of woung healing after month (p < 0.05) 12 Table 3.27.Wound healing time and reperfusion Reperfusion DR (1) IR (2) Wound healing time(month) 2.6 ± 1.7 4.4 ± 1.7 p p 1-2 < 0.05 Conclusion: The woung healing time of direct angiosome group and indirect angiosome group significantly differentiated (p < 0.05) Table 3.28.Lower limb amputationrate No of lower limb (n=91) 12 10 Amputation rate Amputation Toe degree Foot Leg % 13.2 11.0 2.2 Conclusion: Amputation rate was 13.2%, no patient must be amputated leg Chart 3.6.InfrapoplitelPTA restenosis Conclusion: Restenosis rate of infrapopliteal PTA was 34.1%, 50%, 65.9% after months, months, 12 months respectively Bảng 3.30.Restenosis and Clinical stages Clinical stages(1) Restenosis rate – months FU Yes No p Rutherford2 (n, %) Rutherford (n, %) Rutherford (n, %) Rutherford (n, %) Rutherford (n, %) (100) (0) (25) (75) 11 (39.3) 17 (60.7) 10 (25.6) 29 (74.4) (62.5) (37.5) p 1-2 > 0.05 13 (2) Sum 12 28 39 Restenosis rate – months FU (3) Yes (100) (0) (33.3) (66.7) 12 13 (46.4) 15 (53.6) 28 19 (48.7) 20 (51.3) 39 (87.5) (12.5) p 1-3 > 0.05 (100) (0) (33.3) (66.7) 12 19 (67.9) (32.1) 28 26 (66.7) 13 (33.3) 39 (100) (0) p 14< 0.05 Restenosis rate – 12 months FU (4) No Sum Yes No Sum Conclusion: The more severe clinical stages, the higher infrapopliteal restenosis rate Restenosis rate of infrapopliteal PTA after 12 months was 33.3%, 67.9%, 66.7%, 100% of Rutherford 3, Rutherford 4, Rutherford 5, Rutherford respectively Chart 3.7.Infrapoplitel PTA reocclusion Conclusion: Reocclusion rate of infrapopliteal PTA was 18.2%, 25%, 35.6% after months, months, 12 months respectively Table 3.34.Infrapoplitealreintervention Re-intervention rate months FU Re-intervention rate Patient (n= 88) % Patient (n= 88) 5.7 13 14 months FU % 14.8 Re-interventionrate Patient (n= 87) 17 12 months FU % 19.8 Mean duration time of reintervention (month) = 6.0 2.5 Conclusion:Re-intervention rate of infrapopliteal PTA was 14.8%, 19.8% after months, 12 months respectively Mean duration time of re-intervention was 6.0 2.5 months Table 3.35.Mortality of infrapopliteal PTA Mortality month FU (n=91) Mortality months FU (n=91) Mortality months FU (n=91) Mortality 12 months FU (n=91) Patient % Patient % Patient % Patient % 1.1 1.1 2.2 3.3 Conclusion: Mortality of infrapopliteal PTA was 1.1%, 3.3% after month, 12 months respectively (1 acute pneumonia case after month, intracereberalhaemorrahge cases) 3.3 FACTORS INFLUENCING CLINICAL OUTCOMES 3.3.1 Affection of clinical factors Table 3.36.Clinical stages and clinical outcomes Clinical stages(1) Hemodynamic success (2) Clinical success (3) p Rutherford (n, %) Rutherford (n, %) Rutherford (n, %) Rutherford (n, %) Rutherford (n, %) (100) (8.3) (10.7) 12 (29.3) (55.6) Yes (0) 11 (91.7) 25 (89.3) 29 (70.7) (44.4) Sum 12 28 41 No (0) (100) (0) 12 (100) (0) 28 (100) (4,9) 39 (95.1) (11,1) (88.9) No Yes p12< 0.05 p13> 0.05 15 Complications (4) Sum 12 28 41 No (100) (0) 12 (100) (0) 28 (100) (0) 38 (92.7) (7,3) (100) (0) 12 28 38 Yes Sum Conclusion: The more severe clinical stages, the lower success rate of hemodynamics Success rate of hemodynamics was 91.7%, 89.3%, 70.7%, 44.4% of Rutherford 3, Rutherford 4, Rutherford 5, Rutherford respectively Table 3.39.Arterial lesion levels and outcomes Hemodynamic success Yes (2) No Clinical success Sum Yes (3) No Complications Sum Yes (4) No Reintervention months FU (5) Reintervention months FU (6) Reintervention 12 months FU (7) Sum Yes No Sum Yes No Sum Yes No Arterial lesion levels(1) Single- level Multi- level (n, %) (n, %) 21 48 (60) (85.7) 14 (40) (14.3) 35 56 34 54 (97.1) (96.4) (2.9) (3.6) 35 56 (2.9) (3.6) 34 54 (97.1) (96.4) 35 56 (0) (9.3) 34 49 (100) (90.7) 34 54 12 (2.9) (22.2) 33 42 (97.1) (77.8) 33 53 15 (6.1) (28.3) 31 38 (93.9) (71.7) p p 1-2 < 0.05 p 1-3 > 0.05 p 1-4 > 0.05 p 1-5 > 0.05 p 1-6 < 0.05 p 1-7 < 0.05 p14> 0.05 16 Sum 33 53 Conclusion: Multi-level arterial lesion was higher than single-level arterial lesion in hemodynamic success rate (OR = 4), reintervention6 months FU (OR = 17.3), reintervention 12 months FU (OR = 6.1) 3.3.2 Affection of revascularization strategy Table 3.40.Number of tibial artery revascularization and outcomes Number of tibial artery revascularization(1) Wound healing month FU (2) Wound healing months FU (3) Restenosis months FU (4) Restenosis months FU (5) Restenosis 12 months FU (6) Yes No Sum Yes No Sum Yes No Sum Yes No Sum Yes No Sum tibial artery (n, %) (50) (50) 16 13 (81.2) (18.8) 16 (25.8) 23 (74.2) 31 13 (41.9) 18 (58.1) 31 17 (54.8) 14 (45.2) 31 ≥2tibialartery (n, %) (15.6) 27 (84.4) 32 21 (67.7) 10 (32.3) 31 22 (38.6) 35 (61.4) 57 31 (54.4) 26 (45.6) 57 41 (71.9) 16 (28.1) 57 p p 1-2 < 0.05 p 1-3 > 0.05 p 1-4 > 0.05 p 1-5 > 0.05 p 1-6 > 0.05 Conclusion: Wound healing rate after month of tibial artery group was higher than ≥ tibial artery group, 50% vs 15.6% respectively, OR = 5.4 17 Chapter DISCUSSION 4.1 GENERAL CHARACTERISTICS 4.1.1 Clinical characteristics - Mean age was 75.6, the age group ≥80 was 40% Male 67.1%, female 32.9% Risk factors were hypertension (64.7%), diabetes (25.9%), metabolic lipid disorder (25.9%), smoking (24.7%) The proportion of patients with diabetes is lower than that reported in other studies, more men than women are due to differences in smoking rates - Clinical stages were Rutherford (45.1%) and Rutherford (30.8%) Ulcers and gangrene in toes (45.1%) wasmost common.Less common patients with ulcers and gangrene spread the feet and legs (Rutherford 6), is the stage where reperfusion intervention is more difficult 4.1.2 Subclinical characteristics - Mean ABI was 0.56, group ABI 0.4-0.75 was most common (38%) - The artery lesion was majority arefemoral, popliteal–infrapopliteal level (53.8%) and infrapopliteal level (38.5%) Mean tibial artery lesion length was 20.4 cm Infrapopliteal artery lesion classification was TASC D (97.8%) We believe that the above indicators are due to the proportion of patients with diabetes is not so high, the disease has a long time of development, causing arterial lesions was relatively severe 4.2 TECHNICAL CHARACTERISTICS AND CLINICAL 18 OUTCOMES OF INFRAPOPLITEAL PTA 4.2.1 Technical characteristics - Most common vascular access was from the ipsilateralfemoral at the infrapopliteal lesion side (97.8%), antegrade revascularization was 86.8% This is the characteristics of infrapopliteal PTA with the predominant arterial lesion level is the femoral, popliteal – infrapopliteal and infrapopliteal alone, high rate of chronic total occlusion - Reperfusion of tibial artery was 58.2%, reperfusion of ≥ tibial artery was 35.2% Fernandez's (2010) study shows that the rate of revascularization of 1tibial artery was 80% Reperfusion of1 tibial artery to ischemia area is satisfactory, only when reperfusion was failed, it is necessary to reconstructing from or more tibial arteries, in order to increase the effect Maximum indirect perfusion Our direct angiosome rate reached 70.2%; This result is even higher than some reports, like that of Lida (2014) with 63.4% of Soares (2016) only reaching 52.2% - Complications rate was 3.3% (3 cases with mild clinical symptom, recovered rapidly case hematoma, case distal thrombosis and case peritoneal bleeding must be open sugery).Research by Romiti (2008) this rate was 7.8%; Okamoto (2016) announced that 12.3% had complications This rate was lower because the patient was younger, the disease was less coordinated, the clinical level was less severe The reports all showed that the reperfusion below the knee was safer than the surgery 4.2.2 Clinical Outcomes of Infrapopliteal PTA - Technical success was 79.6% The technical success rate in Romiti's study (2008) was 89%,Kok's study (2017) was 75% This ratio depends on the level of the patient's disease and the skill of the 19 physician to intervene - Wound healing rate was 27.1%, 72.3% and 100% after month, months and months respectively.Mean duration of wound healingwas 3.1 1.8 months This rate in Kawarada’ study (2014) was 36.8% and 57.5% after months, months respectively Shiraki’s study (2015) found an average duration of wound healing was 4.2 months Our wound healing rate was higher and the duration was shorter than these studies because our patients often only had ulceration or gangrene in toes - Amputation rate was 13.2%, limb salvage after 12 months was 100% Limb salvage after 12 months of Sadek’ study (2009) was 81%, of Alexandrescu (2009) was 89% Limb salvage is high is the advantage of infrapopliteal PTA - Restenosis rate of infrapopliteal PTA was 34.1%, 50%, 65.9% after months, months, 12 months respectively High restenosis rate is the “Achille heel” of infrapopliteal PTA, which being studied to improve with other techniques (eg drug-coated balloon, stent, atherectomy,…) The restenosis rate after 12 months in Giles (2008) was 61%,Liistro (2013) was 74% - Reocclusion rate of infrapopliteal PTA was 25%, 35.6% after months, 12 months respectively Mustapha's study (2016) found that re-occlusion rate after 12 months was 36.9% In general, reocclusion rate is about half of restenosis rate in the same time - Re-intervention rate of infrapopliteal PTA was 14.8%, 19.8% after months, 12 months respectively.The re-intervention rate after 12 20 months of the study of Lida (2013) was 34%, of Mustapha (2016) was 18.2% The re-intervention depends on lower limb arterial lesions, risk factors control, and most importantly is the level of treatment compliance of patients - Mortality of infrapopliteal PTA was 1.1%, 3.3% after month, 12 months respectively (1 acute pneumonia case after month, intracereberalhaemorrahge cases) Giles (2008) found that the mortality rate after 12 months was 19%, this rate in Romiti's study (2008) was 2.7% The cause of death is due to the severity and associated diseases caused 4.3 FACTORS INFLUENCING CLINICAL OUTCOMES 4.3.1 Affection of clinical factors Clinical stages - The more severe clinical stages, the lower success rate of hemodynamics Success rate of hemodynamics was 91.7%, 89.3%, 70.7%, 44.4% of Rutherford 3, Rutherford 4, Rutherford 5, Rutherford respectively Tsuchiya's (2015) study found that lower extremity arterial disease with Rutherford stage was less amputated (12.3%) and death rate after month (6.7%) than in the Rutherford stage or (rates are 22.7% and 33.3%, respectively) - The more severe clinical stages, the higher infrapopliteal restenosis after 12 months rate Restenosis rate of infrapopliteal PTA after 12 months was 33.3%, 67.9%, 66.7%, 100% of Rutherford 3, Rutherford 4, Rutherford 5, Rutherford respectively Lida (2012) found that without using cilostazol and statins, completely chronic 21 total occlusive lesions were factors that increased the restenosis rate Arterial lesion levels - Multi-level arterial lesion group was higher than single-level arterial lesion group in hemodynamic success rate (85.7% vs 60%, OR = 4), re-intervention rate after months (22.2% vs 2.9%,OR = 17.3) and 12 months (28.3% vs 6.1%, OR = 6.1) Fernandez (2011) found that the multi-level arterial lesion group was higher than the single-level arterial lesion group with the wound healing rate after months (87% vs 69%), the duration time of completely woung healing was faster (7.7 ± 6.6 months vs 11.5 ± 8.8 months) and the limb salvage after 12 months (95% vs 81%) 4.3.2 Affection of revascularization strategy Number of tibial artery revascularizations - Wound healing rate after month of tibial artery group was higher than ≥ tibial artery group (50% vs 15.6% respectively, OR = 5.4) Darling's study (2016) found that the wound healing rate were similar between the two groups, while Kobayashi (2016) found that the reperfusion group of ≥ tibial artery had higher rates of wound healing (87%vs 79%), the time is shorter (83 days vs 142 days) The cause of the difference of the studies is due to intervention strategies, we choose to prioritize reperfusion directly ulcers and gangrene area, if failure new reperfusion or more tibial artery, when some other authors choose to reperfusion as much of the tibial artery as possible Reperfusion properties - Direct angisome reperfusion improved compared to indirect 22 angiosome reperfusion of the rate of wound healing after month (37.1% vs 0%) and duration time of completely woung healing (2.6 ± 1.7 months vs 4.4 ± 1.7 months) The study of Kabra (2013) found that the rate of wound healing after month, months and months was higher in the direct reperfusion group than the indirect reperfusion group (the corresponding ratios were 7.9% vs 5%, 57.6% vs 12.5%, 96.4% vs 83.3% respectively) The fact that direct reperfusion is the first priority in below the knee revascularization, has the greatest effect on the results of wound healing and limb salvage CONCLUSIONS GENERAL CHARACTERISTICS 1.1 Clinical characteristics Mean age was 75.6, the age group ≥80 was 40% Male 67.1%, female 32.9% Risk factors were hypertension (64.7%), diabetes (25.9%), metabolic lipid disorder (25.9%), smoking (24.7%) Clinical stages were Rutherford (45.1%) and Rutherford (30.8%) Ulcers and gangrene in toes (45.1%) wasmost common 1.2 Subclinical characteristics Mean ABI was 0.56, group ABI 0.4-0.75 was most common (38%) The artery lesion was majority arefemoral, popliteal–infrapopliteal level (53.8%) and infrapopliteal level (38.5%) Mean tibial artery lesion length was 20.4 cm Infrapopliteal artery lesion classification was TASC D (97.8%) CLINICAL OUTCOMES OF INFRAPOPLITEAL PTA AND 23 FACTORS INFLUENCING CLINICAL OUTCOMES 2.1 Clinical outcomes of infrapopliteal PTA Technical success was 79.6% Wound healing rate was 27.1%, 72.3% and 100% after month, months and months respectively.Mean duration of wound healingwas 3.1 1.8 months Amputation rate was 13.2%, limb salvage after 12 months was 100% Restenosis rate of infrapopliteal PTA was 34.1%, 50%, 65.9% after months, months, 12 months respectively.Reocclusion rate of infrapopliteal PTA was 25%, 35.6% after months, 12 months respectively Re-intervention rate of infrapopliteal PTA was 14.8%, 19.8% after months, 12 months respectively Complications rate was 3.3% Mortality of infrapopliteal PTA was 1.1%, 3.3% after month, 12 months respectively 2.2 Factors influencing clinical outcomes Clinical factors The more severe clinical stages, the lower success rate of hemodynamics (Hemodynamic success rate was 91.7%, 89.3%, 70.7%, 44.4% of Rutherford 3, Rutherford 4, Rutherford 5, Rutherford respectively) and the higher infrapopliteal restenosis after 12 months rate (12 months restenosis rate of infrapopliteal PTA was 33.3%, 67.9%, 66.7%, 100% of Rutherford 3, Rutherford 4, Rutherford 5, Rutherford respectively) 24 Multi-level arterial lesion group was higher than single-level arterial lesion group in hemodynamic success rate (85.7% vs 60%, OR = 4), re-intervention rate after months (22.2% vs 2.9%,OR = 17.3) and 12 months (28.3% vs 6.1%, OR = 6.1) Revascularization strategy Wound healing rate after month of tibial artery group was higher than ≥ tibial artery group (50% vs 15.6% respectively, OR = 5.4) Direct angisome reperfusion improved compared to indirect angiosome reperfusion of the rate of wound healing after month (37.1% vs 0%) and duration time of completely woung healing (2.6 ± 1.7 months vs 4.4 ± 1.7 months) PROPOSALS We have the following proposals: - Percutaneous Transluminal Angioplasty is an effective method of reperfusion therapy for infrapopliteal arterial lesions - Direct angiosome reperfusion improve the rate and duration of wound healing LIST OF PUBLISHED ARTICLE RELATING TO THESIS Luong Tuan Anh, Pham Thai Giang (2017), “Study on clinical characteristics of lower extremity artery disease with infrapopliteal lesions” Jounal of 108 – Clinical Medicine and Pharmacy, volume 12, pp 28 – 34 Luong Tuan Anh, Le Van Truong, Vu Dien Bien (2017), “A short–term results of Infrapopliteal Percutaneous Transluminal Angioplasty” Jounal of 108 – Clinical Medicine and Pharmacy, volume 12, pp 66 – 72 Luong Tuan Anh, Le Van Truong (2016),”Characters of ABI and Arterial lesions on the below the knee” Journal of Military Pharmaco-Medicince, volume 41, pp 153 – 158 ... extemity arterial disease with infrapopliteal lesions Evaluate mid-term outcomes and factors influencing clinical outcomes of infrapopliteal angioplasty in patient with lower extremity arterial disease. .. Affection of clinical factors Clinical stages - The more severe clinical stages, the lower success rate of hemodynamics Success rate of hemodynamics was 91.7%, 89.3%, 70.7%, 44.4% of Rutherford 3, Rutherford... bypass surgery In which, plain ballooning is the priority method, assessing the effectiveness of normal ballooning with different types of infrapopliteal lesions as well as combining with additional