Impact of Antimicrobial-Resistant Bacterial and Polymicrobial Infection on Wound Healing After Minor Forefoot Amputation in Chronic Limb-Threatening Ischemia With Infection

OBJECTIVES

This study aimed to evaluate the relationship between bacteriological findings and wound healing after minor amputation in the treatment of chronic limb-threatening ischemia (CLTI) with infection.

METHODS

This single-center retrospective study analyzed 135 consecutive limbs with tissue loss and infection from 120 patients who underwent endovascular therapy (EVT) and minor forefoot amputation for CLTI with wound infection between November 2017 and August 2021. The Kaplan-Meier method was used to assess the rate of wound healing after the procedure. The Cox proportional-hazards model was used to examine the impact of bacteriological findings and baseline characteristics on wound healing.

RESULTS

The wound healing rate at 6 months was 72.6%. In a multivariate analysis, in addition to hemodialysis (hazard ratio [HR]=1.73; p=0.009) and amputation above the metatarsophalangeal (MP) joint (HR=1.81; p=0.006), antimicrobial-resistant bacterial infection (HR=1.80, p=0.004) and polymicrobial infection (H=1.51; p=0.049) were predictors of delayed wound healing.

CONCLUSION

Antimicrobial-resistant bacterial infection, polymicrobial infection, hemodialysis, and amputation above the MP joint were independent predictors of delayed wound healing after EVT and minor forefoot amputation in patients with CLTI and bacterial wound infection.

CLINICAL IMPACT

In this single-center retrospective study, we analyzed 136 consecutive limbs with tissue loss and infection from 120 patients who underwent endovascular therapy and minor forefoot amputation for chronic limb-threatening ischemia (CLTI) with wound infection between November 2017 and August 2021. Our main findings were that antimicrobial-resistant bacterial infection, polymicrobial infection, hemodialysis, and amputation above the metatarsophalangeal joint were independent predictors of delayed wound healing after minor amputation. This is the first report of the association between bacteriological studies and wound healing in CLTI with infection, and will be of great help in the future clinical practice.

Infrapopliteal 3-Vessel Occlusive Disease Is the Only Predictor of Wound Recurrence After Complete Wound Healing via Endovascular Therapy in Patients With Chronic Limb-threatening Ischemia

PURPOSE

To determine the predictors of wound recurrence after complete wound healing in patients with chronic limb-threatening ischemia (CLTI) who underwent endovascular therapy (EVT) for infrapopliteal (IP) lesions with consideration of IP arterial anatomic severity, including classification by the Global Limb Anatomic Staging System (GLASS).

MATERIALS AND METHODS

This retrospective single-center study assessed patients with de novo CLTI limbs with tissue loss treated via EVT for IP lesions from September 2016 to May 2021. Among these patients, 149 consecutive limbs from 133 patients who achieved complete wound healing were enrolled. The Kaplan-Meier method was used to estimate the wound recurrence rate after complete wound healing. The Cox proportional hazard model was used to assess the association between baseline characteristics and wound recurrence.

RESULTS

The cumulative wound recurrence rate 1 year after complete wound healing was 30%. The mean time for wound recurrence was 7±5 months. Only IP arterial anatomic characteristics remained as a predictor of wound recurrence, whereas wound status and management, including the Wound, Ischemia, and foot Infection (WIfI) clinical stage and minor amputation, were not associated with wound recurrence. Multivariate analysis revealed independent associations between wound recurrence and IP 3-vessel occlusive disease (hazard ratio, 2.97; 95% confidence interval, 1.39-6.35), but not poor below-the-ankle runoff, IP Peripheral Arterial Calcium Scoring System (PACSS) grade, and the GLASS IP grade.

CONCLUSION

The only independent predictor of wound recurrence after complete wound healing via EVT in patients with CLTI was IP 3-vessel occlusive disease.

CLINICAL IMPACT

In patients with chronic limb-threatening ischemia (CLTI), wound recurrence after complete wound healing remains a challenge, and studies focused exclusively on wound recurrence are still limited. The present study aimed to determine the risk factors for wound recurrence after complete wound healing in patients with CLTI who underwent endovascular therapy (EVT) for infrapopliteal (IP) lesions, with consideration of IP arterial anatomic severity for the first time. The results showed that IP 3-vessel occlusive disease was the only predictor of wound recurrence, whereas wound status/management and other arterial anatomic characteristics including WIfI clinical stages and GLASS grades were not predictors.

Predictors of delayed wound healing after simultaneous endovascular treatment and minor forefoot amputation for chronic limb-threatening ischemia with wound infection

OBJECTIVES

To assess wound healing after simultaneous endovascular treatment (EVT) and minor forefoot amputation and identify the predictors of delayed wound healing in patients with chronic limb-threatening ischemia (CLTI) and bacterial infections of the wounds.

METHODS

In this single-center retrospective cohort study, we evaluated 79 consecutive limbs with tissue loss from 73 CLTI patients who underwent simultaneous EVT and minor forefoot amputation between November 2017 and May 2020. To estimate the rate of wound healing after the simultaneous procedure, we used the Kaplan-Meier method. To assess the association between baseline characteristics and delayed wound healing, we used the Cox proportional hazard model.

RESULTS

All patients who underwent the simultaneous procedure had ischemic wounds with bacterial infection. The rate of wound healing at 6 months reached 82%. The median time for wound healing was 76 days. According to multivariable analysis, Lisfranc/Chopart amputation (hazard ratio (HR) 2.46, 95% confidence interval (CI) 1.09-6.60), absence of above-the-knee (ATK) occlusive lesions (HR 1.89, 95% CI 1.04-3.45), and poor below-the-ankle (BTA) runoff (HR 1.77, 95% CI 1.01-3.11) were independent predictors of delayed wound healing.

CONCLUSION

Lisfranc/Chopart amputation, absence of ATK occlusive lesions, and poor BTA runoff were independent predictors of delayed wound healing after simultaneous EVT and minor forefoot amputation in patients with CLTI and bacterial infections of the wound.

High Global Limb Anatomic Staging System Femoropopliteal Grade is Positively Associated with Wound Healing in Patients with Chronic Limb-Threatening Ischemia Undergoing Endovascular Therapy Only for Femoropopliteal Disease

BACKGROUND

To investigate the prognostic impact of femoropopliteal (FP) arterial anatomic severity including classification by the global limb anatomic staging system (GLASS) on wound healing in patients with chronic limb-threatening ischemia (CLTI) who had undergone endovascular therapy (EVT) only for FP lesions.

METHODS

This was a retrospective single-center study. We treated 349 consecutive de novo CLTI limbs with tissue loss from January 2017 to May 2021. Among these, 91 limbs treated via EVT only for FP lesions were enrolled. We compared the clinical background, infrapopliteal (IP)/FP arterial anatomical characteristics, and EVT results between the limbs with GLASS FP grade 1 or 2 (low GLASS FP, n = 20) and those with GLASS FP grade 3 or 4 (high GLASS FP, n = 71). The Kaplan-Meier method was used to estimate the wound healing rate. The Cox proportional hazard model was used to assess the association between baseline characteristics and wound healing.

RESULTS

No patient underwent EVT for IP lesions. IP arterial anatomical characteristics did not show any significant difference between the low and high GLASS FP groups. The cumulative wound healing rate after EVT was significantly higher in the high GLASS FP group than in the low GLASS FP group (88% vs. 39% at 6 months; P < 0.001). Multivariate analysis revealed that low wound, ischemia, and foot infection (WIfI) clinical stage (stage 1 or 2) (hazard ratio [HR] 2.33; 95% confidence interval [CI] 1.32-4.17) and high GLASS FP (grade 3 or 4) (HR 5.18; 95% CI 1.99-13.51) were independent factors for wound healing.

CONCLUSIONS

High GLASS FP grade was positively associated with wound healing after EVT only for FP lesions.

Successful Percutaneous Fogarty Thrombectomy for Subacute Lower Limb Ischemia Due to Resistant Thrombus in the Popliteal Artery

Patient: Male, 73-year-old

Final Diagnosis: Subacute lower limb ischemia

Symptoms: Coldness • pallor • numbness • rest pain of the right toes

Medication: —

Clinical Procedure: Percutaneous Fogarty thrombectomy

Specialty: Cardiac Surgery • Cardiology

Predictors and outcomes of ischemia-driven target lesion revascularization in deferred lesion based on fractional flow reserve: a multi-center retrospective cohort study

Background

Fractional flow reserve (FFR) has become the gold standard for diagnosing ischemia in angiographically intermediate epicardial coronary artery stenosis. This study investigated the clinical outcomes and predictors of revascularization deferral based on FFR.

Methods

In this retrospective cohort study, we assessed 474 lesions (440 patients) where revascularization was deferred based on the FFR value. Minimum lumen diameter and %-diameter stenosis were measured. Calcification was graded as none, mild, moderate, or heavy. The synergy between percutaneous coronary intervention with taxus and cardiac surgery (SYNTAX) score I was also determined. The primary outcome was ischemia-driven target lesion revascularization (TLR) in deferred lesions within 3 years. Patients were also assigned into two groups based on FFR value.

Results

The average age of the patients was 69.7±10.4 years. The average FFR value was 0.86±0.05. Stable angina pectoris was noted in 298 (67.7%) cases, and in-stent restenosis (ISR) was present in 28 (5.9%). The average SYNTAX score was 7.2±4.2. The 3-year ischemia-driven TLR was 18 lesions (3.8%). Cox proportional hazard model revealed that the SYNTAX score and ISR were independent predictors for TLR in deferred lesions [hazard ratio (HR) =1.10, 95% confidential interval (CI): 1.01–1.19, P=0.03; HR =6.33; 95% CI: 2.25–17.8, P<0.01, respectively]. The deferral group, with a low FFR value, tended to have higher TLR rates than other groups.

Conclusions

Lesions with lower FFR values were associated with a higher incidence of ischemia-driven TLR than those with higher FFR values. SYNTAX score and ISR were predictors for ischemia-driven TLR at 3 years in the deferred lesions.

Diagnostic Accuracy of Diastolic Fractional Flow Reserve for Functional Evaluation of Coronary Stenosis

Background

In the resting conditions, narrowing the window of coronary pressure measurements from the whole cardiac cycle to diastole improves diagnostic performance of coronary pressure–derived physiological index. However, whether this also applies to the hyperemic conditions has not yet been thoroughly evaluated.

Objectives

The purpose of this study was to assess whether diastolic fractional flow reserve (diastolic FFR) has better diagnostic performance in identifying ischemia-causing coronary lesions than conventional FFR in a prospective, multicenter, and independent core laboratory–based environment.

Methods

In this prospective multicenter registry at 29 Japanese centers, we compared the diagnostic performance of FFR, diastolic FFR, resting distal to aortic coronary pressure (Pd/Pa), and diastolic pressure ratio (dPR) using myocardial perfusion scintigraphy (MPS) as the reference standard in 378 patients with single-vessel coronary disease.

Results

Inducible myocardial ischemia was found on MPS in the relevant myocardial territory of the target vessel in 85 patients (22%). In the receiver-operating curve analyses, diastolic FFR had comparable area under the curve (AUC) compared with FFR (AUC_{diastolic FFR}: 0.66; 95% confidence interval [CI]: 0.58-0.73, vs AUC_FFR: 0.66; 95% CI: 0.58-0.74, P = 0.624). FFR and diastolic FFR showed significantly larger AUCs than resting Pd/Pa (0.62; 95% CI: 0.54-0.70; P = 0.033 and P = 0.046) but did not show significantly larger AUCs than dPR (0.62; 95% CI: 0.55-0.70; P = 0.102 and P = 0.113).

Conclusions

Diastolic FFR showed a similar diagnostic performance to FFR as compared with MPS. This result reaffirms the use of FFR as the most accurate invasive physiological lesion assessment. (Diagnostic accuracy of diastolic fractional flow reserve (d-FFR) for functional evaluation of coronary stenosis; UMIN000015906)

Primary percutaneous coronary intervention without stenting using excimer laser and manual thrombectomy in STEMI with duodenal ulcer perforation: a case report

Background

ST-segment elevation myocardial infarction (STEMI) and peptic ulcer perforation are both medical emergencies that require urgent intervention. In case that these time-sensitive medical emergencies present concomitantly, it remains unclear which one should be treated first.

Case summary

An 85-year-old man with melaena, epigastric pain, and severe anaemia was transferred to our emergency department and diagnosed as having inferior STEMI based on electrocardiogram. Emergency coronary angiography (CAG) revealed severe stenosis with thrombus in the proximal right coronary artery. Immediate oesophagogastroduodenoscopy and abdominal computed tomography detected the presence of duodenal ulcer perforation. Primary percutaneous coronary intervention (PCI) without stenting using excimer laser coronary angioplasty and manual thrombectomy was performed under intravascular ultrasound (IVUS) guidance to avoid dual antiplatelet therapy (DAPT). After successful PCI, the perforated viscus was surgically repaired with a laparoscopic omental patch. On Day 7, endoscopic haemostasis treated the oozing of blood from the duodenal ulcer. On Day 21, follow-up CAG and IVUS showed residual stenosis with organized thrombus in the culprit lesion, in which a drug-coated stent was directly implanted. He was discharged with a favourable clinical course on Day 23.

Discussion

We judged that PCI should take precedence over the surgical repair of perforated duodenal ulcer in our case since STEMI was an immediate life-threatening compared to the perforated viscus which had no active exsanguination. Excimer laser coronary angioplasty with manual thrombectomy might be an adequate option to avoid stent deployment and subsequent DAPT in such complex scenarios.

Three-year outcomes after deferral of revascularization based on instantaneous wave-free ratio or fractional flow reserve: insights from the J-CONFIRM Registry

Background

The safety of deferral of revascularization based on instantaneous wave-free ratio (iFR) is established in randomized controlled trials. However, there is little data regarding long-term outcomes after deferral of revascularization based on iFR in real-world practice.

Purpose

We sought to assess clinical outcomes after deferral of revascularization based on iFR in clinical practice as compared with those based on fractional flow reserve (FFR).

Methods

This is a post hoc analysis of the J-CONFIRM registry (long-term outcomes of Japanese patients with deferral of coronary intervention based on fractional flow reserve in multicenter registry), in which 1262 patients with 1447 lesions deferred the revascularization based on FFR. Of these, both FFR and iFR were measured in 399 patients with 452 lesions. The patients were classified into the two groups: the iFR group (iFR &gt;0.89; 308 patients with 348 lesions) and the FFR group (FFR &gt;0.80; 740 patients with 855 lesions). The primary study endpoint was the 3-year target vessel failure (TVF) including cardiac death, target-vessel related myocardial infarction (TVMI), and clinically driven target vessel revascularization (CDTVR).

Results

Mean iFR was 0.96±0.04 in the iFR group. Mean FFR was significantly lower in the iFR group than in the FFR group (0.87±0.05 vs. 0.89±0.05, p=0.002). The iFR group included 35 lesions (11.4%) with FFR ≤0.80. At 3 years, the rate of TVF on a lesion basis were not significantly different between the iFR and FFR groups (8.8% vs. 6.1%, p=0.10), whereas CDTVR rate was significantly higher in the iFR group than in the FFR group (8.5% vs. 5.3%, p=0.044). Cardiac death and TVMI on a patient basis rarely occurred in both groups during the 3-year follow-up (0.33% vs. 0.77%, p=0.47; 0.66% vs. 0.56%, p=0.85, respectively).

Conclusion

At 3 years, TVF rate in deferred lesions was numerically higher in the iFR group than in the FFR group, driven by a higher rate of CDTVR. However, cardiac death and TVMI was very rare in both groups, highlighting the safety of both iFR- and FFR-based deferral of revascularization in daily practice.

Funding Acknowledgement

Type of funding source: None

Paclitaxel-coated Zilver PTX drug-eluting stent treatment does not result in increased long-term all-cause mortality compared to uncoated devices from Japan post-market surveillance study

Purpose

Favorable long-term outcomes with the Zilver PTX drug-eluting stent (DES) in treating patients with femoropopliteal lesions have been demonstrated. A multicenter, prospective, post-market surveillance study (PMS) in Japan evaluated this DES in a real-world patient population. Recently, meta-analysis that grouped both DES and drug-coated balloons (DCB) together indicated a higher incidence of late all-cause mortality for paclitaxel- based devices compared to uncoated balloon or bare-metal stent (BMS) at 2 years up to 5 years. To evaluate the long-term safety of the Zilver PTX DES, compared with BMS using Japan-PMS study.

Methods

The Japan DES PMS had no exclusion criteria and enrolled consecutive patients with symptomatic PAD involving the above-the-knee femoropopliteal arteries. Safety and effectiveness of the DES was evaluated in real-world patients with complex femoropopliteal artery lesions through 5 years. Follow-up in the study is complete. The concurrent Japan BMS PMS also had no exclusion criteria and enrolled consecutive patients with symptomatic PAD involving the above-the-knee femoropopliteal arteries. Patients who were enrolled in the BMS study but who also had a DES placed (n=18) were excluded from the current analysis. Follow-up in the BMS study was only required through 3 years and is complete.

Results

The Japan DES PMS enrolled 904 DES patients, and the Japan BMS PMS enrolled 190 BMS patients. In the DES group, there were 127 deaths through 3 years and 186deaths through 5 years. In the BMS group, there were 22 deaths through 3 years. Through 3 years, the risk of mortality was 15.7% for DES group and 15.3% for BMS group. Through 5 years, the risk of mortality was 25.8% for the DES group. There was no difference in mortality between the two groups (log-rank p=0.92).The Cox proportional hazards model revealed that CLI (p&lt;0.0001), age (p&lt;0.0001), gender (p=0.001), renal failure (p&lt;0.0001) were significantly associated with mortality. Hypercholesterolemia (p=0.004) was associated with lower risk of mortality. Treatment with Zilver PTX (p=0.49) was not associated with mortality. In the covariate analysis of paclitaxel dose, the significant factors were identical to the treatment analysis, and there was no association or trend of paclitaxel dose (p=0.07) with mortality.

Conclusion

Analyses of the paclitaxel-coated Zilver PTX DES utilizing patient-level data from the Japan PMS demonstrated no increase in long-term all-cause mortality. The 5-year results from this real-world, all-comers study continue to show positive long-term outcomes and demonstrate the benefit of the Zilver PTX DES across a broad patient population.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): COOK

Successful Retrieval of a Stuck Guidewire by Guiding Catheter Lock Technique in Renal Artery Stenting

Introduction

The guiding catheter lock technique is a therapeutic technique to increase backup force of the guiding catheter in coronary artery interventions.

Surgical technique

A 71 year old man presented with rapidly declining kidney function resulting from bilateral renal artery stenosis. During the renal artery stenting procedure, the 0.014" guidewire became trapped at the stent's distal edge. Although attempts were made to advance a microcatheter and balloon catheter over the trapped guidewire, these failed because of insufficient pushability of the guiding catheter. Therefore, the guiding catheter lock technique was used with a second guiding catheter, and the guidewire was successfully retrieved.

Discussion

The guiding catheter lock technique facilitated strong pushability to allow for successful retrieval of a stuck guidewire during renal artery stenting.

•

During renal artery stenting, a guidewire was trapped at the stent's distal edge.

•

The stuck guidewire was retrieved using the guiding catheter lock technique.

•

The guiding catheter lock technique can be useful for bailout of a stuck guidewire.

P4704The efficacy of intravascular ultrasound for patients with peripheral artery diseases presenting aorto-iliac artery disease

Background

The use of intravascular ultrasound (IVUS) promotes better clinical outcomes for intervention in complex lesions. However, the data demonstrating whether use of IVUS improves primary patency following stenting for aorto-iliac lesions in patients with peripheral artery disease (PAD) are limited.

Purpose

The purpose of the current study was to investigate the impact of IVUS use on primary patency 12 months after stent implantation for aorto-iliac lesions.

Methods

We analyzed a clinical database of the OMOTENASHI registry (Observational prospective Multicenter registry study on Outcomes of peripheral arTErial disease patieNts treated by AngioplaSty tHerapy in aortoIliac artery), registering symptomatic PAD patients (Rutherford category 2, 3, or 4) undergoing endovascular therapy for aorto-iliac lesions between January 2014 and April 2016 in Japan. The current study analyzed 803 patients who underwent self-expandable stent implantation at 61 centers with the institutional volume known. The primary endpoint was 12-month restenosis, defined as ≥50% stenosis on computed tomography or angiography, or a peak systolic velocity ratio ≥2.5 on duplex ultrasound. When treatment strategies, endovascular procedures and clinical outcomes were compared between the patients treated with IVUS use and those treated without IVUS use, the propensity score matching was performed to minimize the inter-group difference in baseline characteristics.

Results

A total of 545 patients (67.9%) underwent IVUS-supported stent implantation. Patients treated with IVUS use had a lower prevalence of regular dialysis, whereas they had a higher prevalence of TASC II class D and chronic total occlusion. In patients treated with IVUS use, carbon dioxide contrast agent were more often used, and 0.035-inch guidewire was less frequently selected. Implanted stents in these patients were longer and smaller in diameter. The propensity score matching extracted 138 pairs, with no remarkable intergroup difference in baseline characteristics. Procedure time ≤1 hour was less frequent in patients treated with IVUS use; their radiation time was longer. Endovascular strategies, as well as postoperative medication were not significantly different between patients with and without IVUS use. The 12-month restenosis risk was not significantly different between patients with and without IVUS use (10.2% [6.9 to 14.9%] versus 10.3% [5.4 to 18.6%], P=0.99).

Conclusion

IVUS use in aorto-iliac stenting for patients with PAD was not associated with primary patency at 12 months.

Acknowledgement/Funding

None

Exercise-induced Atrioventricular Block with Coronary Artery Stenosis that Appeared Five Years after Bypass Surgery

A 68-year-old man with a history of coronary artery bypass surgery was referred to our hospital because of pre-syncope on effort. During a treadmill exercise electrocardiogram test, the patient developed advanced atrioventricular block associated with dizziness. Coronary angiography revealed significant stenosis of the right coronary artery, which had not existed at the time of the bypass surgery. We implanted drug-eluting stents in the stenotic lesion, and an exercise test showed resolution of the atrioventricular block. Exercise-induced atrioventricular block is rare, and it is necessary to distinguish it from ischemic heart disease, especially in patients with a history of coronary artery disease.

Automatic DPC Code Selection from Electronic Medical Records

Objectives: We extracted index terms related to diseases recorded in hospital discharge summaries and examined the capability of the vector space model to select a suitable diagnosis with these terms.

Methods: By morphological analysis, we extracted index terms and constructed an original dictionary for the discharge summary analysis. We chose 125 different DPC (Japanese DRG system) codes for the diseases, each of which had more than 20 cases. We divided them into two groups. One group consisted of 5927 cases from 2004 fiscal year and was used to generate the document vector space according to the DPC. The other group of 3187 cases was collected to verify the automatic DPC selection by using data from 2005 fiscal year. The top 200 extracted index terms for each disease were used to calculate the weight of each disease.

Results: The DPC code obtained by the calculated similarity was compared with the original codes of patients for 125 DPCs of 3187 cases. Eighty percent of the cases matched the diagnosis of the DPC (first six digits) and 56% of the cases completely matched all 14 digits of the DPC.

Conclusions: We demonstrated that we could extract suitable terms for each disease and obtain characteristics, such as the diagnosis, from the calculated vectors. This technique can be used to measure the qualification of discharge summaries and to integrate discharge summaries among different facilities. By the text mining technique, we can characterize the contents of electronic discharge summaries and deduce diagnoses with the data.

Usefulness of continuous compression using TR Band™ for radial arteriovenous fistula following trans-radial intervention

Arteriovenous fistula (AVF) after trans-radial catheterization is an extremely rare complication. A 61-year-old man experienced a painful swelling in the left radial punctured site. The findings of vascular ultrasound and angiography led to a diagnosis of an iatrogenic radial AVF. We performed continuous compression using a hemostatic band for 24 h after which the radial AVF completely disappeared without vessel occlusion, and no relapse occurred. Eight cases of catheterization-induced radial AVF have been mentioned in the literature, but the treatment has not been noninvasive in any case. This is the first report of an iatrogenic radial AVF that was noninvasively repaired using continuous low-pressure compression with a hemostatic band. <Learning objective: Arteriovenous fistula (AVF) after trans-radial catheterization is a rare complication. The literature reports only 8 cases of catheterization-induced radial AVF and no patient has been cured noninvasively. This is the first report of an iatrogenic radial AVF that was repaired noninvasively. We believe that continuous low-pressure compression using a hemostatic band is an effective therapeutic option for this complication.>.