It has long been accepted that observational analyses have an important role in evaluating use patterns and assessing the safety of different treatments, including cardiovascular devices, in clinical practice. With the proliferation of large electronic databases, there has been increasing interest in using observational analyses to also examine the comparative effectiveness of devices. However, these analyses are often met with skepticism because of concerns about whether they can generate credible evidence about causal effects. This is in part a result of the difficulty in meeting the assumptions necessary to interpret observational associations as causal effects and of the wide variability in analytic rigor. In this review, we outline frameworks and review methods for using observational analyses to answer questions about the effectiveness and safety of cardiovascular devices. We highlight the target trial framework as a practical tool for guiding observational comparative effectiveness analyses. We illustrate how the framework allows investigators planning and conducting observational analyses to organize their activities as responses to 3 prompting questions. First, what is the research question of the study (ie, "What do we want?")? Second, what are the resources-including background knowledge, research concepts, principles and methods, and available data-that can be brought to bear on the research question (ie, "What do we have?")? And third, what specific steps should be taken to use the available resources to answer the research question (ie, "What do we do?")? We focus our exposition on the evaluation of cardiovascular devices, for which randomized trial data are often limited and there is a strong need for real-world evidence. In this setting, real-world evidence is usually derived from observational comparisons of the treatment of interest with relevant comparator groups using data captured during routine care. A principled approach to the planning and conduct of observational analyses can improve the quality of real-world evidence generation and ensure that the results of observational studies on medical devices can support meaningful conclusions about the risks and benefits of new devices.
Publications by Year: 2026
2026
BACKGROUND: AGENT is the only coronary drug-coated balloon (DCB) approved for treatment of in-stent restenosis (ISR) to date. In this study, we describe trends in DCB use and compare characteristics and in-hospital outcomes between patients who received DCB versus alternative treatments.
METHODS: We included patients in the American College of Cardiology National Cardiovascular Disease Registry CathPCI Registry who underwent percutaneous coronary intervention between April 2024 and June 2025 and received DCB, drug-eluting stent (DES), or plain old balloon angioplasty. Treatment groups were compared using standard mean differences.
RESULTS: Between April 2024 and June 2025, 14 946 DCBs were used in 12 337 patients across 704 CathPCI Registry sites. The monthly rate of DCB use for ISR percutaneous coronary intervention grew from <1% to 17.5% during the study period. Of 96 452 ISR procedures performed overall, 9269 (9.61%) involved the use of DCB. DCB procedures were more likely to involve the use of specialty balloons (DCB 45.3% versus DES 17.5% versus plain old balloon angioplasty 28.3%), intravascular imaging (DCB 54.5% versus DES 35.1% versus plain old balloon angioplasty 30.9%), and atherectomy (DCB 14.9% versus DES 6.0% versus plain old balloon angioplasty 7.3%). Among patients treated with DCB, 0.4% experienced myocardial infarction, 0.7% developed cardiogenic shock, 0.2% had an ischemic stroke, and 0.9% died. DCB was separately used in 3459 of 810 483 (0.43%) non-ISR percutaneous coronary interventions. Unadjusted rates of in-hospital adverse outcomes after ISR and non-ISR DCB use were like those for DES (standard mean difference <10%).
CONCLUSIONS: Real-world DCB use is increasing rapidly in the United States, driven by use in ISR lesions but also with growth among non-ISR lesions.
OBJECTIVE: Acute limb ischemia (ALI) is a limb- and life-threatening vascular emergency that necessitates prompt revascularization. While both surgical and endovascular interventions are established treatment modalities, contemporary comparative data remain limited. The study aims to evaluate and compare outcomes between these revascularization strategies.
METHODS: A Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-guided systematic review and meta-analysis were performed. Three databases were searched through January 2026. All studies comparing endovascular versus surgical treatment for ALI were identified. Outcomes of interest included periprocedural and mid-term mortality, major amputation, and reintervention rates. Mid-term outcomes were defined as events occurring at any point during the reported follow-up period. Risk ratios (RRs) or hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted and analyzed using a random-effects model.
RESULTS: Twenty-four studies (5 randomized controlled trials, 2 prospective, and 17 retrospective observational studies) comprising 382 465 patients (endovascular: 172 308; surgical: 210 157) were analyzed. In these studies, there was no difference in periprocedural mortality between endovascular and surgical treatment (RR 0.84, 95% CI 0.62-1.14). Endovascular treatment was associated with lower mid-term mortality compared with surgical revascularization (HR 0.84, 95% CI 0.76-0.94). Major amputation showed a similar trend, with comparable periprocedural risk (RR 0.93, 95% CI 0.51-1.71) and reduced mid-term risk with endovascular therapy (HR 0.84, 95% CI 0.77-0.91). Periprocedural reintervention rates were significantly higher in the endovascular group (RR 1.94, 95% CI 1.80-2.08), while mid-term reintervention rates were comparable (HR 1.79, 95% CI 0.79-4.06).
CONCLUSION: In this contemporary meta-analysis of patients treated for ALI, endovascular revascularization was associated with lower mid-term mortality and major amputation rates, whereas surgical intervention was linked to a lower risk of periprocedural reintervention. These findings underscore the importance of a multidisciplinary approach involving a dedicated vascular team to ensure optimal, patient-tailored management.
CLINICAL TRIAL REGISTRATION: Prospective Register of Systematic Reviews, ID=1042195.Clinical ImpactAcute limb ischemia (ALI) carries high morbidity and mortality, yet comparative data on endovascular versus surgical revascularization are limited. In this meta-analysis of 24 studies including 382 465 patients, periprocedural mortality was similar between approaches, but endovascular therapy reduced mid-term mortality and major amputation risk, despite higher periprocedural reintervention rates. These findings suggest that endovascular-first strategies may be a safe and effective alternative to surgical revascularization. Optimal care requires a multidisciplinary vascular team to tailor interventions, balancing immediate procedural risks with long-term outcomes for each patient.
Individuals with lower extremity peripheral artery disease (LE PAD) represent a subset of patients with atherosclerotic cardiovascular disease that are among the highest risk for major adverse cardiovascular and limb events. Despite this, LE PAD is frequently under diagnosed, and an individual patient's risk for cardiovascular morbidity and limb loss is often underestimated and undertreated. To change the course of PAD disease progression, aggressive secondary prevention therapies are required. This is of particular importance among individuals undergoing surgical or endovascular lower extremity revascularization (LER), who represent the PAD subgroup with the highest risk of cardiovascular and limb adverse events. The cornerstone of secondary prevention is centered on symptom control, lifestyle and behavioural interventions that include exercise therapy, smoking cessation, healthy nutrition and weight management. Individuals with high-risk concomitant comorbidities, such as ongoing smoking, diabetes, and chronic kidney disease, represent an even higher risk population that warrant stringent monitoring and may benefit the most from pharmacological therapies. Guideline-recommended pharmacological therapies include antiplatelet and anticoagulant medications, lipid lowering therapies, diabetes medications, and cilostazol. Despite guideline recommendations, these medical therapies remain under-utilized in patients with PAD. Based on the elevated risk profile of individuals with LE PAD undergoing LER, increased efforts are required to initiate and escalate secondary prevention therapies. To achieve this, the development of effective, patient-centred and scalable implementation strategies remains a priority.
PURPOSE OF REVIEW: Renal denervation has emerged as a new therapeutic option for blood pressure (BP) control and is now incorporated into contemporary hypertension guidelines. Here, we review the evolution of evidence for renal denervation, approaches to assessing treatment response, and emerging technological developments.
RECENT FINDINGS: Early non-sham-controlled trials of renal denervation showed substantial reductions in BP, whereas the first sham-controlled trial, SYMPLICITY HTN-3, yielded neutral findings. To address its limitations, subsequent trials incorporated key design modifications - including strict restriction of changes in background antihypertensive medications, procedural standardization, and separate conduct of trials in "on-medication" and "off-medication" cohorts - and have since consistently demonstrated the efficacy of renal denervation. In these studies, efficacy was assessed primarily by reductions in systolic BP, with additional measures including reductions in diastolic BP and antihypertensive medication burden. Alternative ablative mechanisms (e.g., alcohol-mediated neurolysis) are currently under investigation, along with multi-organ denervation approaches aimed at augmenting BP reduction while providing additional metabolic benefits.
SUMMARY: Evidence supporting renal denervation has continued to accumulate, demonstrating consistent BP reductions. The field is evolving, with new approaches using alternative ablative mechanisms or targeting multi-organ sympathetic pathways on the horizon.
OBJECTIVE: Studies have reported conflicting data regarding the prognostic significance of concomitant deep vein thrombosis (DVT) in acute pulmonary embolism (PE). Understanding the potential differences between PE with and without DVT is crucial for optimizing strategies.
METHODS: Using data from The PERT Consortium Registry, this study examined the association between concomitant DVT and clinical outcomes in patients with predominantly acute intermediate and high-risk PE. A secondary aim was to assess the impact of DVT on treatment selection, particularly the use of advanced therapies.
RESULTS: Among 7,346 patients with acute PE, 5,076 (69%) had concomitant DVT. Patients with DVT were more frequently classified as intermediate-risk compared to patients without DVT, including intermediate-high (59.31% vs 51.9%, <0.001) and intermediate-low risk PE (19.4% vs. 17.7%, <0.001). The presence of DVT was significantly associated with higher odds of receiving advanced therapies (OR 2.49, 95% CI 2.14-2.81), particularly catheter-directed therapy (CDT) (OR 2.44, 95% CI 2.12-2.83), with the strongest association observed in the intermediate-high-risk group (OR 2.67, 95% CI 2.25-3.18). Concomitant proximal DVT was not associated with increased in-hospital mortality (OR 0.87, 95% CI 0.69-1.09), 30-day mortality (OR 0.96, 95% CI 0.77-1.20), 1-year mortality (OR 0.87, 95% CI 0.73-1.03), or ICU admission (OR 1.05, 95% CI 0.93-1.20), after adjustment for advanced therapy use.
CONCLUSIONS: In this large contemporary cohort of predominantly intermediate- and high-risk PE, concomitant DVT was common and associated with more severe presentation and greater use of advanced therapies, but not with higher short- or long-term mortality.
INTRODUCTION: Over the past decade, the inpatient management of pulmonary embolism has undergone a paradigm shift in response to new evidence and the adoption of catheter-directed reperfusion therapies. However, real-world practice patterns remain poorly characterized.
METHODS: This study used Epic's Cosmos database to analyze admissions for pulmonary embolism in the United States between January 1, 2016, and December 31, 2024. Adult inpatient admissions for pulmonary embolism were identified by International Classification of Diseases, Tenth Revision codes documented in the Admit to Inpatient order. Admissions were stratified by severity using established high-risk criteria to allow for a risk-based comparison of treatment strategies. High-risk criteria included the presence of cardiogenic shock, cardiac arrest, the use of vasopressors, dobutamine, extracorporeal membrane oxygenation, or mechanical ventilation at any point during the admission; the remaining admissions were classified as non-high-risk. Trends in patient characteristics, anticoagulation strategies, reperfusion therapies, and cardiopulmonary support were analyzed across the study period.
RESULTS: This study identified a total of 267,094 hospital admissions for pulmonary embolism (mean [SD] age, 63 [17] years; 51.4% female; 71.1% White) between 2016 and 2024. Of these admissions, 5.5% met one or more high-risk criteria, increasing from 4.3% in 2016 to 5.8% in 2024 (p < 0.001). The proportion of patients receiving unfractionated heparin alone increased across non-high-risk (33.2% to 63.0%) and high-risk cases (53.7% to 66.3%). Among non-high-risk admissions, the utilization of reperfusion therapies nearly doubled (5.2% to 10.3%, p = 0.002), primarily driven by a rise in the use of catheter-directed embolectomy. In high-risk admissions, the overall use of reperfusion therapies remained stable (27%-34%, p = 0.135), while catheter-directed embolectomy emerged as the predominant modality. For hemodynamic support of high-risk admissions, vasopressor/dobutamine utilization increased (53.3% to 72.2%) as mechanical ventilation use declined (54.7% to 32.4%).
CONCLUSIONS: These findings help contextualize the extent to which novel therapies and evolving practice patterns have been integrated into real-world care in the United States. Catheter-directed embolectomy has become the dominant reperfusion strategy for pulmonary embolism, reflecting a major shift in practice.
BACKGROUND: Despite current guidelines recommending physiology- and intravascular imaging-guided percutaneous coronary intervention (PCI) in specific lesion subsets, angiography-guided PCI remains common in practice. The comparative effectiveness of these strategies remains uncertain. We aimed to compare clinical outcomes of PCI guided by intravascular imaging or physiological assessment versus conventional angiography.
METHODS: We conducted a systematic review and network meta-analysis of randomized controlled trials, searching PubMed and EMBASE up to May 31, 2025. Eligible studies compared at least 2 of the following 6 guidance modalities in PCI: angiography, intravascular ultrasound (IVUS), optical coherence tomography/optical frequency domain imaging, fractional flow reserve, angiography-derived fractional flow reserve, and instantaneous wave-free ratio. The primary outcome was trial-defined major adverse cardiovascular events (MACEs). Hazard ratios (HRs) with 95% CIs were pooled using a frequentist random-effects network meta-analysis. Subgroup analyses assessed clinical presentation and guidance objectives such as decision making and procedural optimization.
RESULTS: We identified 43 randomized controlled trials involving 39 291 patients. IVUS-guided PCI (HR, 0.69 [95% CI, 0.60-0.79]), optical coherence tomography/optical frequency domain imaging-guided PCI (HR, 0.75 [95% CI, 0.63-0.90]), and fractional flow reserve-guided PCI (HR, 0.81 [95% CI, 0.70-0.95]) were associated with a lower risk of MACEs compared with angiography-guided PCI. Furthermore, IVUS-guided PCI was associated with a lower risk of MACEs compared with instantaneous wave-free ratio-guided PCI (HR, 0.74 [95% CI, 0.55-1.00]). IVUS-guided PCI reduced the risk of MACE in both acute coronary syndrome and non-acute coronary syndrome patients.
CONCLUSIONS: IVUS- and optical coherence tomography/optical frequency domain imaging-guided PCI were superior to angiography-guided PCI in reducing MACEs. Among the physiology-based approaches, only fractional flow reserve showed a clear benefit.
Carotid artery stenting (CAS) is now established as a less invasive alternative to carotid endarterectomy for patients with carotid artery stenosis. Over the past two decades, stent technologies have undergone significant refinements to improve navigability, conformability, and plaque coverage while aiming to reduce periprocedural complications and enhance long-term durability. Current devices are broadly categorized as open-cell, closed-cell, and dual-layer micromesh stents. Open-cell designs provide excellent flexibility in tortuous anatomy but may be limited by reduced plaque scaffolding. Closed-cell stents improve vessel coverage yet sacrifice some adaptability. Dual-layer micromesh stents combine both principles, seeking to prevent plaque prolapse and distal embolization, with encouraging results from prospective studies and registries. Randomized trials such as CREST and ACT-1 have established the overall noninferiority of CAS compared with carotid endarterectomy, while observational data suggest potential advantages of newer micromesh designs. Nonetheless, clinical outcomes remain closely linked to operator expertise, anatomical complexity, and embolic protection strategies. In contemporary practice, CAS represents a validated treatment option, and individualized stent selection based on device-specific characteristics and patient anatomy is essential to optimize procedural safety and long-term stroke prevention.