Tailored risk assessment and forecasting in intermittent claudication.

BACKGROUND: Guidelines recommend cardiovascular risk reduction and supervised exercise therapy as the first line of treatment in intermittent claudication, but implementation challenges and poor patient compliance lead to significant variation in management and therefore outcomes. The development of a precise risk stratification tool is proposed through a machine-learning algorithm that aims to provide personalized outcome predictions for different management strategies. METHODS: Feature selection was performed using the least absolute shrinkage and selection operator method. The model was developed using a bootstrapped sample based on patients with intermittent claudication from a vascular centre to predict chronic limb-threatening ischaemia, two or more revascularization procedures, major adverse cardiovascular events, and major adverse limb events. Algorithm performance was evaluated using the area under the receiver operating characteristic curve. Calibration curves were generated to assess the consistency between predicted and actual outcomes. Decision curve analysis was employed to evaluate the clinical utility. Validation was performed using a similar dataset. RESULTS: The bootstrapped sample of 10 000 patients was based on 255 patients. The model was validated using a similar sample of 254 patients. The area under the receiver operating characteristic curves for risk of progression to chronic limb-threatening ischaemia at 2 years (0.892), risk of progression to chronic limb-threatening ischaemia at 5 years (0.866), likelihood of major adverse cardiovascular events within 5 years (0.836), likelihood of major adverse limb events within 5 years (0.891), and likelihood of two or more revascularization procedures within 5 years (0.896) demonstrated excellent discrimination. Calibration curves demonstrated good consistency between predicted and actual outcomes and decision curve analysis confirmed clinical utility. Logistic regression yielded slightly lower area under the receiver operating characteristic curves for these outcomes compared with the least absolute shrinkage and selection operator algorithm (0.728, 0.717, 0.746, 0.756, and 0.733 respectively). External calibration curve and decision curve analysis confirmed the reliability and clinical utility of the model, surpassing traditional logistic regression. CONCLUSION: The machine-learning algorithm successfully predicts outcomes for patients with intermittent claudication across various initial treatment strategies, offering potential for improved risk stratification and patient outcomes.

Supervised Exercise Therapy for Intermittent Claudication: A Propensity Score Matched Analysis of Retrospective Data on Long Term Cardiovascular Outcomes.

OBJECTIVE: This study aimed to explore the long term outcomes of patients with intermittent claudication (IC) who completed supervised exercise therapy (SET) vs. those who declined or prematurely discontinued SET, focusing on the incidence of chronic limb threatening ischaemia (CLTI), revascularisation, major adverse limb events (MALE), and major adverse cardiovascular events (MACE). METHODS: A retrospective registry analysis of consecutive patients with IC who were referred for SET between March 2015 and August 2016 and followed up for a minimum of five years. Serial univariable analysis and logistic regression were performed to identify the statistically significant clinical variables that were independent predictors of each outcome measure. The resulting statistically significant variables were used to guide 1:1 propensity score matching (PSM) using the nearest neighbour method with a calliper of 0.2. Cox proportional hazards regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association between SET and the outcomes of interest. RESULTS: Two hundred and sixty-six patients were referred to SET between March 2015 and August 2016. Of these, 64 patients completed SET and 202 patients did not. After PSM, 49 patients were analysed in each cohort. The Cox proportional hazards analysis revealed a significant association between completion of SET and revascularisation requirement (HR 0.46 95% CI 0.25 - 0.84; p = .011), completion of SET and progression to CLTI (HR 0.091, 95% CI 0.04 - 0.24; p < .001), completion of SET and MACE (HR 0.52; 95% CI 0.28 - 0.99; p = .05) and completion of SET and MALE (HR 0.28, 95% CI 0.13 - 0.65; p = .003). The Harrell's C index for all of these models was greater than 0.75, indicating good predictive accuracy. CONCLUSION: Completion of SET is associated with better outcomes in patients who completed SET compared with patients who declined or discontinued SET with respect to clinically important cardiovascular outcomes over seven years.

Clinical outcomes following mechanochemical ablation of superficial venous incompetence compared with endothermal ablation: meta-analysis.

BACKGROUND: Mechanochemical ablation (MOCA) is an alternative method to endovenous thermal ablation (EVTA) for the treatment of superficial venous incompetence that does not require tumescent anaesthesia. The aim of this study was to compare the outcomes from RCTs of MOCA versus EVTA. METHODS: A search was conducted in MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL). Meta-analysis inclusion was restricted to RCTs comparing MOCA against EVTA. Outcomes included anatomical occlusion rate, disease-specific quality of life using the Aberdeen Varicose Vein Questionnaire, procedural and postprocedural pain, and rates of venous thromboembolism. RESULTS: Four RCTs were included in the meta-analysis comprising 654 patients. The anatomical occlusion rate at 1 year was lower after MOCA than EVTA (risk ratio 0.85, 95 per cent c.i. 0.78 to 0.91; P < 0.001). No significant differences were detected in procedural pain (mean difference -3.25, -14.25 to 7.74; P = 0.560) or postprocedural pain (mean difference -0.63, -2.15 to 0.89; P = 0.420). There were no significant differences in Aberdeen Varicose Vein Questionnaire score at 1 year (mean difference 0.06, -0.50 to 0.62; P = 0.830) or in incidence of venous thromboembolism (risk ratio 0.72, 95 per cent c.i. 0.14 to 3.61; P = 0.690). CONCLUSION: The rate of successful anatomical occlusion after MOCA is significantly lower than that after EVTA, but there is no difference in procedural and postprocedural pain between the two interventions. Long-term data are required to assess the impact of the reduced vein occlusion rate on clinical outcomes such as quality of life and reintervention.

The current first-line treatment for varicose veins uses heat to block the diseased veins and is called endovenous thermal ablation (EVTA). Mechanochemical ablation (MOCA) is an alternative method of treatment using a chemical and a fast-spinning wire to block the veins instead. The potential benefits of MOCA include less pain and fewer complications. The aim of this study was to identify high-quality clinical trials comparing MOCA with EVTA, and to assess any differences in the results of treatment. The results showed that MOCA was less successful in blocking the diseased veins than EVTA. There were no differences in the amount of pain or discomfort during or after the procedures (which was low). At 1 year, those treated with both techniques reported the same quality of life. Both techniques were effective over 1 year in terms of improving quality of life; however, the potential benefits of MOCA were not clearly proven in the trials, and the poorer rates of successfully blocking the veins may cause the varicose veins to come back sooner, or the quality-of-life improvement to be shorter lived. There was no evidence to support MOCA replacing EVTA as the first-line treatment in the majority of patients, but it is a viable treatment for selected people.

A pilot study of lens extraction in the management of acute primary angle-closure glaucoma.

PURPOSE: To describe a pilot study of lens extraction in the management of acute primary angle-closure glaucoma (APACG) in Chinese patients. DESIGN: Interventional case series. METHODS: A prospective case series of patients presented with APACG at a tertiary eye hospital in Xiamen, China. All the patients had intensive medical treatment followed by immediate phacoemulsification and posterior chamber intraocular lens implantation under topical anesthesia. RESULTS: There were 18 patients who were seen with APACG who had phacoemulsification and posterior chamber intraocular lens implantation under topical anesthesia. There was a 9.0-mm Hg drop in mean preoperative and first day postoperative intraocular pressure (22.8 vs 13.8 mm Hg, P =.012) and a 10.2-mm Hg drop in mean preoperative and seventh-day postoperative intraocular pressure (22.8 vs 13.2 mm Hg, P =.002). CONCLUSIONS: This pilot study indicates that phacoemulsification and posterior chamber intraocular lens implantation may be useful in the treatment of primary acute angle-closure glaucoma in Chinese patients. Further study with longer follow-up is needed.