Daily Cardiology Research Analysis
Top cardiology advances today include: a multicenter randomized trial showing a drug-eluting resorbable scaffold outperforms angioplasty below-the-knee in chronic limb-threatening ischemia at 2 years; a prespecified randomized analysis demonstrating QFR-guided PCI reduces MACE in low-risk ACS with fewer stents; and a prospective study defining a high prevalence of transthyretin cardiac amyloidosis in older Black individuals with heart failure, informing targeted screening.
Summary
Top cardiology advances today include: a multicenter randomized trial showing a drug-eluting resorbable scaffold outperforms angioplasty below-the-knee in chronic limb-threatening ischemia at 2 years; a prespecified randomized analysis demonstrating QFR-guided PCI reduces MACE in low-risk ACS with fewer stents; and a prospective study defining a high prevalence of transthyretin cardiac amyloidosis in older Black individuals with heart failure, informing targeted screening.
Research Themes
- Peripheral revascularization innovations for CLTI
- Physiology-guided PCI (QFR) in acute coronary syndromes
- Targeted screening for transthyretin cardiac amyloidosis in high-risk populations
Selected Articles
1. Drug-Eluting Resorbable Scaffold Versus Balloon Angioplasty for Below-the-Knee Peripheral Artery Disease: 2-Year Results From the LIFE-BTK Trial.
In the multicenter, subject-blinded LIFE-BTK RCT (n=261), a drug-eluting resorbable scaffold improved 2-year efficacy versus balloon angioplasty for infrapopliteal lesions in CLTI, with 68.8% vs 45.4% freedom from composite failure. The scaffold reduced restenosis and reinterventions while maintaining a similar safety profile.
Impact: This is the first randomized evidence with 2-year outcomes demonstrating superiority of a resorbable drug-eluting scaffold over PTA for below-the-knee disease in CLTI, a high-risk population with limited options.
Clinical Implications: Consider DRS as an alternative to PTA for selected infrapopliteal lesions in CLTI to improve patency and reduce reinterventions, with attention to lesion complexity and calcification severity.
Key Findings
- At 2 years, freedom from the composite of amputation, vessel occlusion, clinically driven TLR, or binary restenosis was 68.8% with DRS vs 45.4% with PTA.
- DRS reduced restenosis and reintervention rates compared with PTA while maintaining a comparable safety profile.
- Predictor analyses for efficacy and TLR were performed, supporting patient/lesion selection for DRS.
Methodological Strengths
- Multicenter, subject-blinded randomized controlled trial design
- Prespecified 2-year efficacy and safety endpoints with clinical adjudication and trial registration
Limitations
- Selected population with predominantly noncomplex, mildly-to-moderately calcified lesions limits generalizability
- Sample size (n=261) and 2-year horizon; longer-term durability unknown
Future Directions: Head-to-head comparisons against contemporary DCB/DES strategies and longer-term (≥5-year) durability and limb outcomes are needed; refine selection criteria using lesion imaging.
BACKGROUND: Limited treatment options exist for infrapopliteal disease in patients with chronic limb-threatening ischemia (CLTI), a condition associated with a high risk of limb loss. Interventional management of diseased infrapopliteal vessels with percutaneous transluminal angioplasty (PTA) is associated with high rates of restenosis and reintervention. In the LIFE-BTK randomized controlled trial (Pivotal Investigation of Safety and Efficacy of BRS Treatment-Below the Knee), the drug-eluting resorbable scaffold (DRS) demonstrated superior 12-month efficacy compared with PTA in a selected CLTI population with predominantly noncomplex, mildly to moderately calcified lesions. This report presents the 2-year safety and efficacy outcomes of the Esprit BTK DRS system in the LIFE-BTK randomized trial comparing DRS with PTA for treatment of infrapopliteal vessels and CLTI. METHODS: The LIFE-BTK trial was a multicenter, subject-blinded, randomized controlled trial enrolling 261 patients with CLTI who were randomized 2:1 to receive either DRS or PTA. The revised primary efficacy end point was freedom from target limb amputation, target vessel occlusion, clinically driven target lesion revascularization, or binary restenosis. The primary safety end point was freedom from major adverse limb events and perioperative death. Predictors of efficacy and clinically driven target lesion revascularization were analyzed along with subgroup assessments. RESULTS: At 2 years, the primary efficacy end point was observed in 68.8% of the DRS group versus 45.4% of the PTA group ( CONCLUSIONS: At 2 years, the Esprit BTK DRS demonstrated improved efficacy compared with PTA in maintaining arterial patency, preventing restenosis, and reducing revascularization rates while maintaining a comparable safety profile. These findings support the Esprit BTK scaffold as a promising treatment option for appropriately selected patients with infrapopliteal artery disease and CLTI. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04227899.
2. Two-year outcomes of quantitative flow ratio-based physiology-guided percutaneous coronary intervention in patients with low-risk acute coronary syndrome: a prespecified secondary analysis of FAVOR III China.
In a prespecified subgroup (n=2,371) of the FAVOR III China RCT, QFR-guided PCI in low-risk ACS altered plans in 23.6%, increasing deferral and reducing stent use, and achieved lower MACE at 1 and 2 years versus angiography guidance. This supports physiology-guided lesion selection beyond stable CAD.
Impact: Extends randomized evidence for QFR-guided PCI into low-risk ACS with durable 2-year benefit and fewer implants, signaling potential practice change in lesion selection and resource utilization.
Clinical Implications: In low-risk ACS, QFR-guided assessment can safely defer non-ischemic lesions, reduce stent implantation, and lower MACE compared with angiography guidance; programs should build QFR capability for real-time physiology.
Key Findings
- Among 2,371 low-risk ACS patients, QFR guidance changed management in 23.6%, increasing PCI deferral (reported 19.0%).
- QFR-guided strategy reduced MACE at 1 and 2 years versus angiography guidance.
- QFR guidance reduced stent utilization by favoring ischemia-driven lesion selection.
Methodological Strengths
- Prespecified subgroup analysis within a prospective, multicenter randomized trial
- Clinically relevant 2-year follow-up with procedural and outcome data
Limitations
- Subgroup analysis; not originally powered for the low-risk ACS cohort separately
- Open-label design; QFR calculation quality and generalizability to high-risk ACS remain considerations
Future Directions: Validate in broader ACS spectra (including higher-risk NSTEMI/STEMI), assess cost-effectiveness, and integrate QFR into streamlined workflows and automated pipelines.
BACKGROUND: The benefits of physiology-guided management in acute coronary syndrome (ACS) remain inconclusive due to limited evidence. In our FAVOR III China trial, a quantitative flow ratio (QFR)-based physiology-guided strategy versus standard angiography guidance improved the 1-year primary outcome among participants with coronary artery disease (CAD). We aimed to investigate, in a prespecified analysis, the outcomes of QFR-based physiological guidance in the FAVOR III China participants with low-risk ACS. METHODS: This pre-specified secondary analysis included patients diagnosed with low-risk ACS who were enrolled in the FAVOR III China trial. The trial was a prospective, randomised study that assigned 3825 CAD patients to receive QFR-guided or angiography-guided percutaneous coronary intervention (PCI) at 26 hospitals in China between December, 2018 and January, 2020. The primary outcome of interest for this study was major adverse cardiac events (MACE), defined as a composite of all-cause death, myocardial infarction, and ischaemia-driven revascularisation, at 1-year (primary outcome of FAVOR III China) and 2-year follow-up. Secondary outcomes included PCI strategy change and the procedural characteristics. FAVOR III China is registered with ClinicalTrials.gov, NCT03656848. FINDINGS: Of the 2371 participants with low-risk ACS (93.7% unstable angina and 6.3% non-ST elevation myocardial infarction [NSTEMI]) in the FAVOR III China trial, the QFR-guided strategy changed the original intended treatment plan in 23.6% of the low-risk ACS patients, resulting in more PCI deferrals (19.0 INTERPRETATION: Our findings favoured the superiority of QFR-guided lesion selection strategy over standard angiography guidance in reducing long-term MACE for the low-risk ACS population. The benefits associated with QFR need to be confirmed by future studies with extended follow-up. FUNDING: The National High Level Hospital Clinical Research Funding, the Capital's Funds for Health Improvement and Research, the Chinese Academy of Medical Sciences, the Noncommunicable Chronic Diseases National Science and Technology Major Project, Shanghai Municipal Health Commission "Top Priority Research Centre", and Shanghai Shenkang Hospital Development Centre.
3. Transthyretin Cardiac Amyloidosis in Older Black and Hispanic Individuals With Heart Failure.
In a prospective multicenter cross-sectional study of 646 older Black and Caribbean Hispanic HF patients, ATTR-CA prevalence was 6.66%, with 55.8% ATTRwt and 44.2% V142I-mediated ATTRv. Prevalence was highest in Black men >75 years (17.17%), supporting targeted screening in this population.
Impact: Defines disease burden and genotype distribution of ATTR-CA in an under-studied, high-risk population, directly informing screening strategies and earlier initiation of disease-modifying therapy.
Clinical Implications: Systematic evaluation for ATTR-CA (bone scintigraphy with light-chain exclusion and TTR genotyping) should be prioritized in older Black HF patients, particularly men >75 years; identify V142I carriers to guide counseling and therapy.
Key Findings
- Overall ATTR-CA prevalence was 6.66% among 646 older Black and Caribbean Hispanic HF patients.
- Of ATTR-CA cases, 55.8% were ATTRwt and 44.2% were V142I ATTRv; V142I allele prevalence was 5.6%, with 52.8% manifesting ATTR-CA among carriers.
- Prevalence was higher in Black vs Hispanic participants (7.82% vs 2.15%) and highest in Black men >75 years (17.17%).
Methodological Strengths
- Prospective, multicenter, standardized diagnostic algorithm with radionuclide imaging and genotyping
- Adequate sample size with stratified prevalence estimates and confidence intervals
Limitations
- Cross-sectional design limits causal inference and outcome associations
- Generalizability beyond included US cities and to other ethnic groups may be limited
Future Directions: Prospective screening-outcome studies to test whether early detection improves morbidity/mortality; cost-effectiveness of targeted screening; implementation pathways in community HF clinics.
IMPORTANCE: Transthyretin cardiac amyloidosis (ATTR-CA) is an underdiagnosed but treatable cause of heart failure (HF) in older individuals that occurs in the context of normal wild-type (ATTRwt-CA) or an abnormal inherited (ATTRv-CA) TTR gene variant. While the most common inherited TTR variant, V142I, occurs in 3% to 4% of self-identified Black Americans and is associated with excess morbidity and mortality, the prevalence of ATTR-CA in this at-risk population is unknown. OBJECTIVE: To define the prevalence of ATTR-CA and proportions attributable to ATTRwt-CA or ATTRv-CA among older Black and Caribbean Hispanic individuals with HF. DESIGN, SETTING, AND PARTICIPANTS: This prospective, multicenter, cross-sectional study was conducted in several major US cities (Boston, Massachusetts; New York, New York; and New Haven, Connecticut) among individuals who self-identified as Black or Caribbean Hispanic older than 60 years with HF. Participants were enrolled between May 2019 and June 2024, and data analysis was conducted from June 2024 to May 2025. MAIN OUTCOMES AND MEASURES: ATTR-CA was determined by radionuclide imaging, with blood testing to exclude light-chain amyloidosis and genotyping to determine TTR gene variant. Echocardiographic, biochemical, physical performance, and quality-of-life data were collected. RESULTS: Among 646 participants, median (IQR) participant age was 73 (66-80) years, 329 (50.6%) were women, 550 (85.1%) identified as Black, and 186 (28.8%) identified as Caribbean Hispanic. Median (IQR) left ventricular wall thickness was 13 (12-14) mm, and median (IQR) left ventricular ejection fraction was 61% (55%-66%). Overall prevalence of ATTR-CA was 6.66% (95% CI, 4.73%-8.58%), of whom 24 (55.8%) had ATTRwt-CA and 19 (44.2%) had ATTRv-CA owing to V142I. Overall prevalence of V142I allele was 5.6%, and of those, 19 (52.8%) had ATTRv-CA. Prevalence of ATTR-CA was 8.15% (95% CI, 5.15%-11.15%) in men and 5.20% (95% CI, 2.79%-7.61%) in women (P = .13). Prevalence of ATTR-CA was 7.82% (95% CI, 5.57%-10.06%) in Black participants and 2.15% (95% CI, 0.07%-4.24%) in Hispanic participants (P = .004). Among Black participants aged 75 years or younger, ATTR-CA was observed in 3.42% of participants (95% CI, 1.43%-5.40%) compared to 14.04% (95% CI, 9.53%-18.54%) of those older than 75 years (P < .001). Among Black male participants older than 75 years, prevalence of ATTR-CA was 17.17% (95% CI, 9.74%-24.60%). CONCLUSIONS AND RELEVANCE: In this cross-sectional study, ATTR-CA was an important cause of HF in older Black individuals with HF, particularly in men older than 75 years. Approximately half of V142I carriers with HF had ATTR-CA, while 55.8% of all ATTR-CA cases had normal TTR genotype. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03812172.