Publications

BACKGROUND: Drug-eluting stents (DESs) with controlled antiproliferative drug release reduce restenosis risk, but durable polymers can delay healing and inhibit reendothelialization. The Firehawk biodegradable polymer sirolimus-eluting stent (BP-SES) has a fully biodegradable sirolimus-containing polymer coating localized to recessed abluminal grooves on the stent surface and delivers roughly one-third the drug dose of other DESs.

OBJECTIVES: We report the primary results of the TARGET-IV NA (Firehawk Rapamycin Target Eluting Coronary Stent North American Trial) randomized controlled trial comparing clinical outcomes with BP-SES vs currently used second-generation DESs.

METHODS: The TARGET-IV NA study was a prospective, multicenter, single-blind, 1:1 randomized noninferiority trial comparing the BP-SES with control in North America and Europe among patients undergoing percutaneous coronary intervention for chronic or acute coronary syndromes. The primary endpoint was target lesion failure (TLF) at 12 months (composite of cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization). The primary analysis (intention-to-treat) tested noninferiority of BP-SES vs control using an absolute margin of 3.85% and 1-sided α of 0.025. Noninferiority-powered secondary endpoints were tested in an optical coherence tomography substudy (endpoint: mean neointimal hyperplasia thickness) and an angiography substudy (endpoint: in-stent late lumen loss).

RESULTS: A total of 1,720 patients (mean age 66 years; 74% male) with 2,159 lesions were randomly allocated to receive either BP-SES (860 patients, 1,057 lesions) or control second-generation DES (860 patients, 1,084 lesions). A total of 61% of patients presented with stable coronary disease, 32% had unstable angina, and 7% had non-ST-segment elevation myocardial infarction (NSTEMI) or recent ST-segment elevation myocardial infarction. The rate of TLF with BP-SES was noninferior to control at 12 months (3.4% vs 3.3%, absolute risk difference 0.13%, upper bound 97.5% CI: 2.03, Pnoninferiority < 0.0001). Cardiac death, myocardial infarction, and stent thrombosis rates were similar between groups. Angiographic follow-up was available in 104 patients (97.2% of those enrolled in the angiographic substudy) and 128 (94.1%) lesions. At 13 months, the powered secondary endpoint of mean in-stent late lumen loss was 0.149 ± 0.263 mm for BP-SES and 0.327 ± 0.463 mm for control (least squares mean difference: -0.178; 90% CI: -0.2943 to -0.0632; Pnoninferiority < 0.0001). The optical coherence tomography substudy included 37 patients (42 lesions) with no difference in mean neointimal hyperplasia thickness between groups at 13 months (Pnoninferiority = 0.01).

CONCLUSIONS: The biodegradable polymer sirolimus-eluting stent was noninferior to currently used second-generation DES with regard to TLF at 1 year. (Firehawk® Rapamycin Target Eluting Coronary Stent North American Trial; NCT04562532).

BACKGROUND: Transcatheter edge-to-edge repair of the mitral valve (mTEER) reduced a hierarchical end point that included death and heart failure hospitalization in COAPT (Cardiovascular Outcomes Assessment of the MitraClip Percutaneous Therapy for Heart Failure Patients With Functional Mitral Regurgitation Trial). However, the magnitude to which mTEER increases the number of days a patient spends at home (DAH) in the first few years after treatment, a patient-centered end point not captured routinely in clinical trials, has not been evaluated. We compared 1- and 2-year DAH among patients with functional mitral regurgitation and heart failure randomized to mTEER plus medical therapy versus medical therapy alone (control) by linking the COAPT trial to comprehensive health care claims data.

METHODS AND RESULTS: We linked data from COAPT trial participants to Medicare fee-for-service claims. DAH was calculated as the number of days alive and spent outside a hospital, skilled nursing facility, inpatient rehabilitation, long-term acute care hospital, emergency department, or observation stay after randomization. Treatment groups were compared using quantile regression to calculate the area under the curve of cumulative distribution functions. We linked 271 patients (mTEER 136/302, control 135/312) for a 2-year follow-up. Mean±SD DAH at 1 year was 312.0±95.6 in mTEER and 298.1±107.5 in controls with similar area under the curve (difference 13.9 days [-10.5 to 38.3], P=0.26). DAH at 2 years was 577.2±235.6 in mTEER and 518.2±253.0 in control with a higher area under the curve in mTEER (difference 59.0 days [0.07 to 117.9], P=0.0497).

CONCLUSIONS: In the COAPT trial linked to Medicare claims, patients randomized to mTEER spent a similar number of DAH at 1 year but more time at home at 2 years compared with medical therapy alone.

BACKGROUND: Lower-limb amputation rates in patients with chronic limb-threatening ischemia vary across the United States, with marked disparities in amputation rates by gender, race, and income status. We evaluated the association of patient, hospital, and geographic characteristics with the intensity of vascular care received the year before a major lower-limb amputation and how intensity of care associates with outcomes after amputation.

METHODS: Using Medicare claims data (2016-2019), beneficiaries diagnosed with chronic limb-threatening ischemia who underwent a major lower-limb amputation were identified. We examined patient, hospital, and geographic characteristics associated with the intensity of vascular care received the year before amputation. Secondary objectives evaluated all-cause mortality and adverse events following amputation.

RESULTS: Of 33 036 total Medicare beneficiaries undergoing major amputation, 7885 (23.9%) were due to chronic limb-threatening ischemia; of these, 4988 (63.3%) received low-intensity and 2897 (36.7%) received high-intensity vascular care. Mean age, 76.6 years; women, 38.9%; Black adults, 24.5%; and of low income, 35.2%. After multivariable adjustment, those of low income (odds ratio, 0.65 [95% CI, 0.58-0.72]; P<0.001), and to a lesser extent, men (odds ratio, 0.89 [95% CI, 0.81-0.98]; P=0.019), and those who received care at a safety-net hospital (odds ratio, 0.87 [95% CI, 0.78-0.97]; P=0.012) were most likely to receive low intensity of care before amputation. High-intensity care was associated with a lower risk of all-cause mortality 2 years following amputation (hazard ratio, 0.79 [95% CI, 0.74-0.85]; P<0.001).

CONCLUSIONS: Patients who were of low-income status, and to a lesser extent, men, or those cared for at safety-net hospitals were most likely to receive low-intensity vascular care. Low-intensity care was associated with worse long-term event-free survival. These data emphasize the continued disparities that exist in contemporary vascular practice.

BACKGROUND: Artificial intelligence (AI)-enabled electrocardiography (ECG) can be used to predict risk of future disease and mortality but has not yet been adopted into clinical practice. Existing model predictions do not have actionability at an individual patient level, explainability, or biological plausibi. We sought to address these limitations of previous AI-ECG approaches by developing the AI-ECG risk estimator (AIRE) platform.

METHODS: The AIRE platform was developed in a secondary care dataset (Beth Israel Deaconess Medical Center [BIDMC]) of 1 163 401 ECGs from 189 539 patients with deep learning and a discrete-time survival model to create a patient-specific survival curve with a single ECG. Therefore, AIRE predicts not only risk of mortality, but also time-to-mortality. AIRE was validated in five diverse, transnational cohorts from the USA, Brazil, and the UK (UK Biobank [UKB]), including volunteers, primary care patients, and secondary care patients.

FINDINGS: AIRE accurately predicts risk of all-cause mortality (BIDMC C-index 0·775, 95% CI 0·773-0·776; C-indices on external validation datasets 0·638-0·773), future ventricular arrhythmia (BIDMC C-index 0·760, 95% CI 0·756-0·763; UKB C-index 0·719, 95% CI 0·635-0·803), future atherosclerotic cardiovascular disease (0·696, 0·694-0·698; 0·643, 0·624-0·662), and future heart failure (0·787, 0·785-0·789; 0·768, 0·733-0·802). Through phenome-wide and genome-wide association studies, we identified candidate biological pathways for the prediction of increased risk, including changes in cardiac structure and function, and genes associated with cardiac structure, biological ageing, and metabolic syndrome.

INTERPRETATION: AIRE is an actionable, explainable, and biologically plausible AI-ECG risk estimation platform that has the potential for use worldwide across a wide range of clinical contexts for short-term and long-term risk estimation.

FUNDING: British Heart Foundation, National Institute for Health and Care Research, and Medical Research Council.

BACKGROUND: Late career physicians (LCPs; physicians working beyond age 65 to 75 years) may be at higher risk for delivering unsafe care. To oversee LCPs, some health care organizations (HCOs) have adopted LCP policies requiring cognitive, physical, and practice performance screening assessments. Despite recent controversies, little is known about the content and implementation of such policies.

OBJECTIVE: To characterize key features of LCP policies and the perspectives of medical leaders responsible for policy development and implementation.

DESIGN: Mixed-methods study using content analysis and key informant interviews.

SETTING: 29 U.S. HCOs with LCP policies active in 2020.

PARTICIPANTS: 21 purposively sampled interviewees in physician leadership roles at 18 HCOs.

MEASUREMENTS: Descriptive statistics of policy features and content analysis of interviews.

RESULTS: Although policies had many commonalities-mandatory universal screening at a trigger age around 70 years, a strategy of screening followed by in-depth assessment of positive results, and commitment to patient safety as the key motive-they varied substantially in the testing required, funding, processes after a positive screening result, and decision making around concerning results. Policies prioritized institutional discretion in interpreting and responding to test results; many lacked clear language about appeals or other procedural protections for physicians. Leaders were generally satisfied with policies but reported preemptive retirements as physicians approached the screening age and cautioned that substantial investment in cultivating physicians' buy-in was required for successful rollout.

LIMITATIONS: Sampled policies and interviews may not be representative of all HCOs. The analysis excluded the experiences of HCOs that tried and failed to implement LCP screening.

CONCLUSION: Policies about LCPs are considered successful by institutional leaders. Policy variations and early adopters' implementation experiences highlight opportunities to improve physician acceptance and program rigor.

PRIMARY FUNDING SOURCE: The Greenwall Foundation.