Faculty Bibliography

Inflammation has been demonstrated to negatively impact patients in the peri-ACS period. This narrative review outlines the inflammatory response in ACS, highlighting the role of the NLRP3 inflammasome pathway following acute plaque rupture and coronary intervention and its potential as a pharmacologic target. RECENT: nvestigators have leveraged medications targeting the NLRP3 inflammasome currently used for other inflammatory pathologies, including colchicine, tocilizumab and anakinra. Investigation into these drugs in the peri-ACS period has yielded varying results, with the most encouraging findings in ACS patients treated with tocilizumab. More conflicting data exists for the role of colchicine and anakinra, with many studies limited in their power to detect clinical outcomes and heterogeneity in their patient populations and endpoints. Despite conflicting data, the NLRP3 remains an attractive therapeutic target in the peri-ACS period. Further investigation is required to prove benefit and safety with large clinical trials adequately powered for clinical outcomes.

BACKGROUND:Clinical guidelines have concluded that there are insufficient data to provide recommendations for the hemoglobin threshold for the use of red cell transfusion in patients with acute myocardial infarction (MI) and anemia. After the recent publication of the Myocardial Infarction and Transfusion (MINT) trial, we performed an individual patient-level data meta-analysis to evaluate the effect of restrictive versus liberal blood transfusion strategies. METHODS:We conducted searches in major databases. Eligible trials randomly assigned patients with MI and anemia to either a restrictive (i.e., transfusion threshold of 7-8 g/dl) or liberal (i.e., transfusion threshold of 10 g/dl) red cell transfusion strategy. We used individual patient data from each trial. The primary outcome was a composite of 30-day mortality or MI. RESULTS:We included 4311 patients from four trials. The primary outcome occurred in 334 patients (15.4%) in the restrictive strategy and 296 patients (13.8%) in the liberal strategy (relative risk [RR] 1.13, 95% confidence interval [CI], 0.97 to 1.30). Death at 30 days occurred in 9.3% of patients in the restrictive strategy and in 8.1% of patients in the liberal strategy (RR 1.15, 95% CI, 0.95 to 1.39). Cardiac death at 30 days occurred in 5.5% of patients in the restrictive strategy and in 3.7% of patients in the liberal strategy (RR 1.47, 95% CI, 1.11 to 1.94). Heart failure (RR 0.89, 95% CI, 0.70 to 1.13) was similar in the transfusion strategies. All-cause mortality at 6 months occurred in 20.5% of patients in the restrictive strategy compared with 19.1% of patients in the liberal strategy (hazard ratio 1.08, 95% CI, 1.05 to 1.11). CONCLUSIONS:Pooling individual patient data from four trials did not find a definitive difference in our primary composite outcome of MI or death at 30 days. At 6 months, a restrictive transfusion strategy was associated with increased all-cause mortality. (Partially funded by a grant from the U.S. National Heart, Lung, and Blood Institute [R01HL171977].).

BACKGROUND/UNASSIGNED:The optimal hemoglobin threshold to guide red blood cell (RBC) transfusion for patients with acute myocardial infarction (MI) and anemia is uncertain. OBJECTIVE/UNASSIGNED:To estimate the efficacy of 4 individual hemoglobin thresholds (<10 g/dL [<100 g/L], <9 g/dL [<90 g/L], <8 g/dL [<80 g/L], and <7 g/dL [<70 g/L]) to guide transfusion in patients with acute MI and anemia. DESIGN/UNASSIGNED:Prespecified secondary analysis of the MINT (Myocardial Ischemia and Transfusion) trial using target trial emulation methods. (ClinicalTrials.gov: NCT02981407). SETTING/UNASSIGNED:144 clinical sites in 6 countries. PARTICIPANTS/UNASSIGNED:3492 MINT trial participants with acute MI and a hemoglobin level below 10 g/dL. INTERVENTION/UNASSIGNED:Four transfusion strategies to maintain patients' hemoglobin concentrations at or above thresholds of 10, 9, 8, or 7 g/dL. Protocol exceptions were permitted for specified adverse clinical events. MEASUREMENTS/UNASSIGNED:Data from the MINT trial were leveraged to emulate 4 transfusion strategies and estimate per protocol effects on the composite outcome of 30-day death or recurrent MI (death/MI) and 30-day death using inverse probability weighting. RESULTS/UNASSIGNED:The 30-day risk for death/MI was 14.8% (95% CI, 11.8% to 18.4%) for a <10-g/dL strategy, 15.1% (CI, 11.7% to 18.2%) for a <9-g/dL strategy, 15.9% (CI, 12.4% to 19.0%) for a <8-g/dL strategy, and 18.3% (CI, 14.6% to 22.0%) for a <7-g/dL strategy. Absolute risk differences and risk ratios relative to the <10-g/dL strategy for 30-day death/MI increased as thresholds decreased, although 95% CIs were wide. Findings were similar and imprecise for 30-day death. LIMITATION/UNASSIGNED:Unmeasured confounding may have persisted despite adjustment. CONCLUSION/UNASSIGNED:The 30-day risks for death/MI and death among patients with acute MI and anemia seem to increase progressively with lower hemoglobin concentration thresholds for transfusion. However, the imprecision around estimates from this target trial analysis precludes definitive conclusions about individual hemoglobin thresholds. PRIMARY FUNDING SOURCE/UNASSIGNED:National Heart, Lung, and Blood Institute.

BACKGROUND/UNASSIGNED:Calcified coronary lesions are a challenge for percutaneous coronary interventions (PCIs). Coronary intravascular lithotripsy (IVL) is a novel calcium modification technology approved for commercial use in February 2021, but little is known about its uptake in US clinical practice. METHODS/UNASSIGNED:We described trends in use of calcium modification strategies, variation in use across hospitals, and predictors of calcium modification and IVL use in PCI. We included National Cardiovascular Data Registry CathPCI Registry patients who underwent PCI between April 1, 2018, and December 31, 2022. We examined trends and hospital variation in calcium modification and IVL use. We used multivariate hierarchical logistic regression to identify predictors of calcium modification and IVL use at hospitals in 2022. RESULTS/UNASSIGNED:Of 2,733,494 PCIs across 1676 hospitals over 4.75 years, 11.4% were performed with calcium modification. Coronary IVL use increased rapidly from 0% of PCIs in Q4 2020 to 7.8% of PCIs in Q4 2022, which was accompanied by an overall increase in use of all calcium modification strategies (11.1%-16.0%) during this period with a slight corresponding decrease in coronary atherectomy use (5.4%-4.4%). In 2022, there was wide variation in IVL use across hospitals (median, 3.86%; IQR, 0%-8.19%), with IVL being the most common calcium modification strategy in 48% of hospitals. The treating hospital was the strongest predictor of calcium modification (median odds ratio [OR], 2.49; 95% CI, 2.40-2.57) and IVL use (median OR, 2.89; 95% CI, 2.74-3.04). CONCLUSIONS/UNASSIGNED:IVL has rapidly changed the landscape of calcium modification use for PCI, although there remains wide variation across hospitals.

When selecting an anticoagulant, clinicians consider individual patient characteristic, the treatment indication, drug pharmacology, and safety and efficacy as demonstrated in randomized trials. An ideal anticoagulant prevents thrombosis with little or no increase in bleeding. Direct oral anticoagulants represent a major advance over traditional anticoagulants (e.g., unfractionated heparin, warfarin) but still cause bleeding, particularly from the gastrointestinal tract which can limit their use. Epidemiological studies indicate that patients with congenital factor XI (FXI) deficiency have a lower risk of venous thromboembolism (VTE) and ischemic stroke (IS) than non-deficient individuals, and do not have an increased risk of spontaneous bleeding, even with severe deficiency. These observations provide the rationale for targeting FXI as a new class of anticoagulant. Multiple FXI inhibitors have been introduced and several are being evaluated in Phase III trials. In this review, we explain why drugs that target FXI may be associated with a lower risk of bleeding than currently available anticoagulants and summarize the completed and ongoing trials.

The field of interventional cardiology (IC) has evolved dramatically over the past 40 years. Training and certification in IC have kept pace, with the development of accredited IC fellowship training programs, training statements, and subspecialty board certification. The application process, however, remained fragmented with lack of a universal process or time frame. In recent years, growing competition among training programs for the strongest candidates resulted in time-limited offers and high-pressure situations that disadvantaged candidates. A grassroots effort was recently undertaken by a Society for Cardiovascular Angiography & Interventions task force, to create equity in the system by establishing a national Match for IC fellowship. This manuscript explores the rationale, process, and implications of this endeavor.

BACKGROUND:The MINT trial raised concern for harm from a restrictive versus liberal transfusion strategy in patients with acute myocardial infarction (MI) and anemia. Type 1 and type 2 MI are distinct pathophysiological entities that may respond differently to blood transfusion. This analysis sought to determine if the effects of transfusion varied among patients with a type 1 or a type 2 MI and anemia. We hypothesized that the liberal transfusion strategy would be of greater benefit in type 2 than in type 1 MI. METHODS:We compared rates of death or MI at 30 days in patients with type 1 (n=1460) and type 2 (n=1955) MI and anemia who were randomly allocated to a restrictive (threshold of 7 to 8 g/dL) or a liberal (threshold of 10 g/dL) transfusion strategy. RESULTS:= 0.16). CONCLUSIONS:The concern for harm with a restrictive transfusion strategy in patients with acute MI and anemia raised in the MINT primary outcome manuscript may be more apparent in patients with type 1 than type 2 MI. CLINICAL TRIAL REGISTRATION/BACKGROUND:ClinicalTrials.gov number, NCT02981407.