Clinical Research Directory

The Effect of a Multimodal Preventive Intervention in Patients With Asymptomatic Peripheral Artery Disease

This pilot study, the PilotPreAPAD study, will be carried out to check whether the key parts of the planned Prevention in asymptomatic Arterial Disease (PreAPAD) study will work in practice. In phase one, it will test the screening process for asymptomatic arterial disease and the prevalence of the disease in the screened population to help estimate the sample size needed before starting the larger randomized multi centre PreAPAD study. In phase two, the pilot will test the study protocol, the data collection tools and how acceptable the intervention will be to participants. Peripheral artery disease is a disease where the arteries in the legs are narrowed by atherosclerosis causing pain in the affected limb during exercise and resting pain, ulcers and tissue loss in the more severe stage. Many people, however, are in the stage where they have no leg symptoms, even though they have narrowed arteries, the asymptomatic stage. Despite having no symptoms, they have almost double the risk of developing angina, heart attack, stroke, or dying prematurely-similar to those with more advanced disease. The disease can be easily detected by measuring the blood pressure in the ankle and comparing it to the blood pressure in the arm. This is called the Ankle-Brachial Index (ABI). Measuring ABI makes it possible to identify people at higher risk of future heart and vascular events-risks that can potentially be prevented. The PreAPAD study that is being planned aims to examine how preventive strategies affect heart- and other vascular events, quality of life, and disease progression in men and women with asymptomatic peripheral artery disease. Patients with diabetes, high blood pressure, COPD, or a history of smoking will be screened with ABI measurements to detect asymptomatic disease. The multimodal intervention that will be tested includes a health discussion with a nurse, participation in a health course, individualized exercise advice from a physiotherapist, exercise training, and medication to manage risk factors for cardiovascular disease if needed.

ECG Low Ejection Fraction Detection and Guiding in AI Navigated Treatment Era

Asymptomatic left ventricular systolic dysfunction (ALVSD), identified as a key component of stage B heart failure (HF) by AHA/ACC guidelines, is a common precursor to clinically overt HF. This progressive chronic disease affects over 23 million people worldwide and leads to significant morbidity, mortality, and healthcare costs. Although ALVSD presents a relatively lower risk compared to symptomatic reduced ejection fraction HF, it remains associated with a 1.6-fold increase in the risk of incident HF, a 2.13-fold increase in cardiovascular mortality, and a 1.46-fold increase in all-cause mortality. The prevalence of ALVSD ranges from 3% to 6%, at least twice that of symptomatic HF. To prevent progression to symptomatic heart failure and associated morbidities and mortalities, guideline-directed medical therapy, including ACEIs/ARBs or beta-blockers, is essential for patients with ALVSD. However, distinguishing individuals with ALVSD from the general population is challenging due to the lack of symptoms. Effective screening methods are crucial to identify individuals with ALVSD. Traditionally, diagnosing ALVSD involves screening asymptomatic populations using transthoracic echocardiography (TTE), which is costly, time-consuming, and inconvenient for patients. Other screening methods, such as laboratory tests for brain natriuretic peptide (BNP) or N- terminal pro-atrial natriuretic peptide (NT-proBNP), have insufficient diagnostic performance. Previous research proposed an AI-based alarm system (AI-S) to screen patients for ALVSD, demonstrating greater accuracy than BNP screening and improved accessibility compared to widespread echocardiography. AI-S demonstrated a sensitivity of 92.6% (standard error \[SE\] 0.042) for detecting medium-risk ALVSD patients and 63% (SE 0.154) for high-risk ALVSD patients, with a specificity of 92.7% (SE 0.003) for medium-risk patients and 98.7% (SE 0.002) for high-risk patients. AI-S is accuracy, noninvasive, highly accessible in local medical clinics, less time-consuming, and cost-effective, making it a valuable screening tool for identifying ALVSD prior to echocardiography or other confirmatory diagnostic methods. To date, no randomized controlled trial has assessed the cost-effectiveness and impact of AI-assisted screening tools for heart failure prevention in Asians. The ECG AI-Guided Screening for Low Ejection Fraction (EAGLE) trial reported a 32% increase in diagnosing of low left ventricular ejection fraction (defined as LVEF ≤50%) within 90 days of the ECG. However, this population was not Asian, and randomization involved primary care teams rather than participants. Therefore, this randomized controlled trial is designed to evaluate the impact of AI-S on diagnosing low ejection fraction in Asians, its cost-effectiveness, and the incidence of worsening HF (defined as admission for HF or HF-related emergency department visits).