Faculty Bibliography

Background: Myocardial infarction with non-obstructive coronary arteries (MINOCA) occurs in 6-15% of MI and disproportionately affects women. Scientific statements recommend multi-modality imaging in MINOCA to define the underlying cause. We performed coronary optical coherence tomography (OCT) and cardiac magnetic resonance imaging (CMR) to assess mechanisms of MINOCA. Methods: In this prospective, multicenter, international, observational study, we enrolled women with a clinical diagnosis of MI. If invasive coronary angiography revealed <50% stenosis in all major arteries, multi-vessel OCT was performed, followed by CMR (cine imaging, late gadolinium enhancement, and T2-weighted imaging and/or T1 mapping). Angiography, OCT, and CMR were evaluated at blinded, independent core laboratories. Culprit lesions identified by OCT were classified as definite or possible. The CMR core laboratory identified ischemia-related and non-ischemic myocardial injury. Imaging results were combined to determine the mechanism of MINOCA, when possible. Results: Among 301 women enrolled at 16 sites, 170 were diagnosed with MINOCA, of whom 145 had adequate OCT image quality for analysis; 116 of these underwent CMR. A definite or possible culprit lesion was identified by OCT in 46.2% (67/145) of participants, most commonly plaque rupture, intra-plaque cavity or layered plaque. CMR was abnormal in 74.1% (86/116) of participants. An ischemic pattern of CMR abnormalities (infarction or myocardial edema in a coronary territory) was present in 53.4% of participants undergoing CMR (62/116). A non-ischemic pattern of CMR abnormalities (myocarditis, takotsubo syndrome or non-ischemic cardiomyopathy) was present in 20.7% (24/116). A cause of MINOCA was identified in 84.5% of the women with multi-modality imaging (98/116), higher than with OCT alone (p<0.001) or CMR alone (p=0.001). An ischemic etiology was identified in 63.8% of women with MINOCA (74/116), a non-ischemic etiology was identified in 20.7% (24/116), and no mechanism was identified in 15.5% (18/116). Conclusions: Multi-modality imaging with coronary OCT and CMR identified potential mechanisms in 84.5% of women with a diagnosis of MINOCA, three-quarters of which were ischemic and one-quarter of which were non-ischemic, alternate diagnoses to MI. Identification of the etiology of MINOCA is feasible and has the potential to guide medical therapy for secondary prevention. Clinical Trial Registration: URL: https://clinicaltrials.gov Unique Identifier: NCT02905357.

OBJECTIVE:To investigate the impact of ischemic and bleeding risk factors on long-term clinical outcomes of patients with diabetes mellitus (DM) undergoing percutaneous coronary intervention (PCI) with everolimus-eluting stents. BACKGROUND:Second-generation drug-eluting stents have substantially improved outcomes after PCI in the general population; however, DM patients continue to experience high rates of ischemic and bleeding complications. METHODS:DM patients from the pooled XIENCE V registry were divided into high or low bleeding and ischemic risk groups (HBR, LBR, HIR, and LIR) based on established bleeding (age ≥ 75 years; chronic kidney disease; anemia; prior stroke; oral anticoagulation; thrombocytopenia; prior major bleeding) and ischemic (acute coronary syndrome; prior myocardial infarction [MI]; ≥3 stents implanted; ≥3 vessels treated; ≥3 lesions treated; stent length > 60 mm; bifurcation treated with ≥2 stents; chronic total occlusion) risk factors. The primary outcomes were major adverse cardiac events (MACE; cardiac death, MI, or stent thrombosis) and major bleeding at 4-year follow-up. RESULTS:A total of 3,704 DM patients were divided into four groups (21.5% LBR/LIR; 39.0% LBR/HIR; 15.6% HBR/LIR; 23.9% HBR/HIR). Compared with LBR/LIR patients, those at HBR/HIR and HBR/LIR had a significantly higher risk of MACE (HR (95% CI) 2.7 (1.9-3.9) and 2.2 (1.5-3.2), respectively) and major bleeding (2.7 (1.6-4.8) and 2.6 (1.4-4.7), respectively), while LBR/HIR patients did not. CONCLUSIONS:Among DM patients undergoing PCI, presence of bleeding risk factors was associated with a higher risk of both ischemic and bleeding events, whereas commonly used features of ischemic risk did not impact long-term clinical outcomes.

Dual antiplatelet therapy (DAPT) is key for the prevention of recurrent ischemic events after percutaneous coronary intervention (PCI), however, it increases the risk of bleeding complications. While new generation drug-eluting stents have been shown superior to bare-metal stents after a short DAPT course, the optimal DAPT duration in patients at high bleeding risk (HBR) remains to be determined. TRIAL DESIGN: The XIENCE Short DAPT program consists of three prospective, single-arm studies (XIENCE 90, XIENCE 28 Global and XIENCE 28 USA) investigating 3- or 1-month DAPT durations in HBR patients undergoing PCI with the XIENCE stent. The XIENCE 90 study is being conducted in the US and enrolled 2047 subjects who discontinued DAPT at 3months if they were free from myocardial infarction (MI), repeat coronary revascularization, stroke, or stent thrombosis. The XIENCE 28 program includes the USA study, enrolling 642 patients in US and Canada, and the Global study, enrolling 963 patients in Europe and Asia. In XIENCE 28, patients were to discontinue DAPT at 1month post-PCI if event-free. The primary hypothesis for both XIENCE 90 and XIENCE 28 is that a short DAPT regimen will be non-inferior to a conventional DAPT duration with respect to the composite of all-cause death or MI. Patients enrolled in the prospective multicenter post-market XIENCE V USA study will be used as historical control group in a stratified propensity-adjusted analysis. CONCLUSIONS: The XIENCE Short DAPT Program will provide insights into the safety and efficacy of two abbreviated DAPT regimens of 3- and 1-month duration in a large cohort of HBR patients undergoing PCI with the XIENCE stent.

BACKGROUND:With newer generation drug eluting stents (DES), the minimal duration of dual antiplatelet therapy (DAPT) recommended by guidelines has been reduced to 6 months in patients with stable coronary artery disease. Whether shorter duration of DAPT is safe in patients presenting with acute coronary syndrome (ACS) remains controversial. Our aim of this study was to investigate the optimal DAPT duration (≤3 months vs. 6 months vs. 12 months vs. >12 months) among patients with ACS undergoing percutaneous coronary intervention (PCI). METHODS:PUBMED and EMBASE were searched through January 2020 for randomized controlled trials of DAPT duration in patients with ACS. The ischemic outcomes were all-cause death, myocardial infarction, and stent thrombosis. The safety outcome was major and/or clinically relevant bleeding. RESULTS:Our search identified 14 eligible trials enrolling a total of 31,837 patients comparing different DAPT duration in patients with ACS. Short-term DAPT (≤3 months or 6 months) did not increase ischemic outcomes compared to long-term DAPT (12 months and >12 months). For bleeding outcomes, ≤3 months DAPT was associated with significant reduction in bleeding compared to 6 months, 12 months or >12 months DAPT (OR [95% CI]: 0.60 [0.37-0.98]; 0.68 [0.54-0.85] and 0.43 [0.34-0.54], respectively). These findings were similar when limited to 2nd generation DES. CONCLUSIONS:Data from this meta-analysis of randomized trials support short-term (≤3 months and 6 months) DAPT in patients with ACS undergoing PCI. Guidelines might need to consider short-term DAPT even in patients presenting with ACS, especially in this era of newer generation DES.

BACKGROUND:Mechanical circulatory support (MCS) with Impella or intra-aortic balloon pump (IABP) is used for high-risk percutaneous coronary intervention (PCI) and/or for cardiogenic shock (CS) due to acute myocardial infarction. We aimed to investigate the efficacy and safety of Impella or IABP when compared with no MCS using a network meta-analysis of randomized controlled trials (RCTs). METHODS:EMBASE and MEDLINE were searched through February 2020 for RCT evaluating efficacy of Impella vs. IABP vs. no MCS in patients undergoing high-risk PCI or CS. The primary efficacy outcome was 30 day or in-hospital all-cause mortality whereas the primary safety outcomes were major bleeding and vascular complications. RESULTS:= 1.5%). CONCLUSIONS:Neither Impella nor IABP decreased all-cause short-term mortality when compared with no MCS for high-risk PCI and/or CS. Moreover, Impella increased major bleeding compared with no MCS.

In the era of evidence-based medicine, systematic reviews and meta-analyses are considered at the top of evidence hierarchy. Despite the almost exponential increase in the number of published meta-analyses over the course of the last decades, only a small minority of them is of high quality, with major flaws involving every aspect of the meta-analytic process. The strength of a meta-analysis is closely linked to the quality of the included studies. Once preliminary phases are completed, it is vital that selected papers undergo a thorough quality assessment, using the most appropriate tools among those available. Analytical approaches must be tailored to the nature of the extracted data and the specific purpose of the meta-analysis. Appraisal of heterogeneity is a key step to inform subgroup or meta-regression analyses. The solidity of the results of the main analysis (especially in meta-analyses of observational studies or studies with high heterogeneity) should be tested by means of pertinent sensitivity analyses. Finally, the investigators should be aware of the possibility of publication bias and make efforts to assess it using qualitative and quantitative methods. The aim of the second part of this expert review is to provide guidance on how to appropriately perform trial level meta-analyses, with particular focus on the quality assessment of the included studies, the choice of the appropriate statistical approach, the methods to deal with heterogeneity (including subgroup, meta-regression and sensitivity analyses), and the appraisal of publication bias.

OBJECTIVE:To evaluate the impact of COVID-19 pandemic migitation measures on of ST-elevation myocardial infarction (STEMI) care. BACKGROUND:We previously reported a 38% decline in cardiac catheterization activations during the early phase of the COVID-19 pandemic mitigation measures. This study extends our early observations using a larger sample of STEMI programs representative of different US regions with the inclusion of more contemporary data. METHODS:Data from 18 hospitals or healthcare systems in the US from January 2019 to April 2020 were collecting including number activations for STEMI, the number of activations leading to angiography and primary percutaneous coronary intervention (PPCI), and average door to balloon (D2B) times. Two periods, January 2019-February 2020 and March-April 2020, were defined to represent periods before (BC) and after (AC) initiation of pandemic mitigation measures, respectively. A generalized estimating equations approach was used to estimate the change in response variables at AC from BC. RESULTS:Compared to BC, the AC period was characterized by a marked reduction in the number of activations for STEMI (29%, 95% CI:18-38, p < .001), number of activations leading to angiography (34%, 95% CI: 12-50, p = .005) and number of activations leading to PPCI (20%, 95% CI: 11-27, p < .001). A decline in STEMI activations drove the reductions in angiography and PPCI volumes. Relative to BC, the D2B times in the AC period increased on average by 20%, 95%CI (-0.2 to 44, p = .05). CONCLUSIONS:The COVID-19 Pandemic has adversely affected many aspects of STEMI care, including timely access to the cardiac catheterization laboratory for PPCI.

The number of cardiac surgical meta-analyses and systematic reviews published in the last decades has constantly increased, paralleling the exponential growth observed in virtually all other medical fields. However, meta-analyses are open to methodological flaws if best practices are not strictly followed. Assessment of the appropriateness of the research question is a crucial first step. Once a protocol has been developed, this should be registered before the work is initiated. The cornerstone of any systematic review or meta-analysis is a rigorous, comprehensive, and most of all reproducible search which follows a prespecified and clear strategy. Eligibility criteria must be discussed and agreed upon in advance to guide final study selection, which ultimately lays the foundation for subsequent data extraction. In case of missing or partially reported data, the authors of the original paper should be contacted. Adherence to rigorous methodological rules at each of these stages will warrant availability of good quality data for formal statistical analyses. The aim of the first part of this expert review is to discuss the limits and pitfalls of the meta-analytic approach and provide guidance on how to perform trial level meta-analyses, with particular reference to the identification of an appropriate research question, the definition and registration of the protocol, the search strategy, the study selection and the data abstraction.

Atherosclerotic cardiovascular disease (ASCVD) remains an important contributor of morbidity and mortality in patients with chronic kidney disease (CKD). CKD is recognized as an important risk enhancer that identifies patients as candidates for more intensive low-density lipoprotein (LDL) cholesterol lowering. However, there is controversy regarding the efficacy of lipid-lowering therapy, especially in patients on dialysis. Among patients with CKD, not yet on dialysis, there is clinical trial evidence for the use of statins with or without ezetimibe to reduce ASCVD events. Newer cholesterol lowering agents have been introduced for the management of hyperlipidemia to reduce ASCVD, but these therapies have not been tested in the CKD population except in secondary analyses of patients with primarily CKD stage 3. This review summarizes the role of hyperlipidemia in ASCVD and treatment strategies for hyperlipidemia in the CKD population.

A patient with coronavirus disease 19 (COVID-19) developed acute myocardial infarction (AMI) complicated by extensive coronary thrombosis and cardiogenic shock. She underwent percutaneous coronary intervention and placement of a mechanical circulatory support device but subsequently died from shock. This report illustrates the challenges in managing patients with COVID-19, AMI, and cardiogenic shock.