Coronary Spasm Testing with Acetylcholine: A Powerful Tool for a Personalized Therapy of Coronary Vasomotor Disorders.

Coronary vasomotor disorders (CVD) are characterized by transient hypercontraction of coronary vascular smooth muscle cells, leading to hypercontraction of epicardial and/or microvascular coronary circulation. CVDs play a relevant role in the pathogenesis of ischemia, angina and myocardial infarction with non-obstructive coronary arteries. Invasive provocative testing with intracoronary Acetylcholine (ACh) administration is the gold standard tool for addressing CVD, providing relevant therapeutic and prognostic implications. However, safety concerns preclude the widespread incorporation of the ACh test into clinical practice. The purpose of this review is to shed light on the pathophysiology underlying CVD and on the clinical role of the ACh test, focusing on safety profile and prognostic implications. We will also discuss contemporary evidence on the management of CVD and the role of the ACh test in driving a personalized approach of patients with CVD.

Predicting the response to acetylcholine in ischemia or infarction with non-obstructive coronary arteries: The ABCD score.

BACKGROUND AND AIMS: Acetylcholine (ACh) provocation testing can detect vasomotor disorders in patients with ischemia and non-obstructed coronary arteries (INOCA) or myocardial infarction and non-obstructed coronary arteries (MINOCA). We aimed to derive and validate a simple risk score to predict a positive ACh test response. METHODS: We prospectively enrolled consecutive INOCA and MINOCA patients undergoing ACh provocation testing. Patients were split in two cohorts (derivation and validation) according to time of enrolment. The score was derived in 386 patients (derivation cohort) and then validated in 165 patients (validation cohort). RESULTS: 551 patients were enrolled, 371 (67.3%) INOCA and 180 (32.7%) MINOCA. ACh test was positive in 288 (52.3%) patients. MINOCA, myocardial bridge (MB), C-reactive protein (CRP) and dyslipidaemia were independent predictors of a positive ACh test in the derivation cohort. The ABCD (Acute presentation, Bridge, CRP, Dyslipidaemia) score was derived: 2 points were assigned to MINOCA, 3 to MB, 1 to elevated CRP and 1 to dyslipidaemia. The ABCD score accurately identified patients with a positive ACh test response with an AUC of 0.703 (CI 95% 0.652-0.754,p < 0.001) in the derivation cohort, and 0.705 (CI 95% 0.626-0.784, p < 0.001) in the validation cohort. In the whole population, an ABCD score ≥4 portended 94.3% risk of a positive ACh test and all patients with an ABCD score ≥6 presented a positive test. CONCLUSIONS: The ABCD score could avoid the need of ACh provocation testing in patients with a high score, reducing procedural risks, time, and costs, and allowing the implementation of a tailored treatment strategy. These results are hypothesis generating and further research involving larger cohorts and multicentre trials is needed to validate and refine the ABCD score.

Vaccines and Myocardial Injury in Patients Hospitalized for COVID-19 Infection: the CardioCOVID-Gemelli Study.

BACKGROUND: Myocardial injury is prevalent among patients hospitalized for COVID-19. However, the role of COVID-19 vaccines in modifying the risk of myocardial injury is unknown. OBJECTIVES: To assess the role of vaccines in modifying the risk of myocardial injury in COVID-19. METHODS: We enrolled COVID-19 patients admitted from March 2021 to February 2022 with known vaccination status and ≥1 assessment of hs-cTnI within 30 days from the admission. The primary endpoint was the occurrence of myocardial injury (hs-cTnI levels >99th percentile upper reference limit). RESULTS: 1019 patients were included (mean age 67.7±14.8 years, 60.8% male, 34.5% vaccinated against COVID-19). Myocardial injury occurred in 145 (14.2%) patients. At multivariate logistic regression analysis, advanced age, chronic kidney disease and hypertension, but not vaccination status, were independent predictors of myocardial injury. In the analysis according to age tertiles distribution, myocardial injury occurred more frequently in the III tertile (≥76 years) compared to other tertiles (I tertile:≤60 years;II tertile:61-75 years) (p<0.001). Moreover, in the III tertile, vaccination was protective against myocardial injury (OR 0.57, CI 95% 0.34-0.94; p=0.03), while a previous history of coronary artery disease was an independent positive predictor. In contrast, in the I tertile, chronic kidney disease (OR 6.94, 95% CI 1.31-36.79, p=0.02) and vaccination (OR 4.44, 95% CI 1.28-15.34, p=0.02) were independent positive predictors of myocardial injury. CONCLUSIONS: In patients ≥76 years, COVID-19 vaccines were protective for the occurrence of myocardial injury, while in patients ≤60 years, myocardial injury was associated with previous COVID-19 vaccination. Further studies are warranted to clarify the underlying mechanisms.

A Machine Learning Predictive Model of Bloodstream Infection in Hospitalized Patients.

The aim of the study was to build a machine learning-based predictive model to discriminate between hospitalized patients at low risk and high risk of bloodstream infection (BSI). A Data Mart including all patients hospitalized between January 2016 and December 2019 with suspected BSI was built. Multivariate logistic regression was applied to develop a clinically interpretable machine learning predictive model. The model was trained on 2016-2018 data and tested on 2019 data. A feature selection based on a univariate logistic regression first selected candidate predictors of BSI. A multivariate logistic regression with stepwise feature selection in five-fold cross-validation was applied to express the risk of BSI. A total of 5660 hospitalizations (4026 and 1634 in the training and the validation subsets, respectively) were included. Eleven predictors of BSI were identified. The performance of the model in terms of AUROC was 0.74. Based on the interquartile predicted risk score, 508 (31.1%) patients were defined as being at low risk, 776 (47.5%) at medium risk, and 350 (21.4%) at high risk of BSI. Of them, 14.2% (72/508), 30.8% (239/776), and 64% (224/350) had a BSI, respectively. The performance of the predictive model of BSI is promising. Computational infrastructure and machine learning models can help clinicians identify people at low risk for BSI, ultimately supporting an antibiotic stewardship approach.

Coronary physiology thresholds associated with microvascular obstruction in myocardial infarction.

OBJECTIVES: To ascertain whether invasive assessment of coronary physiology soon after recanalisation of the culprit artery by primary percutaneous coronary intervention is associated with the development of microvascular obstruction by cardiac magnetic resonance in patients with ST-segment elevation myocardial infarction (STEMI). METHODS: Between November 2020 and December 2021, 102 consecutive patients were prospectively enrolled in five tertiary centres in Italy. Coronary flow reserve (CFR) and index of microvascular resistance (IMR) were measured in the culprit vessel soon after successful primary percutaneous coronary intervention. Optimal cut-off points of IMR and CFR to predict the presence of microvascular obstruction were estimated, stratifying the population accordingly in four groups. A comparison with previously proposed stratification models was carried out. RESULTS: IMR>31 units and CFR≤1.25 yielded the best accuracy. Patients with IMR>31 and CFR≤1.25 exhibited higher microvascular obstruction prevalence (83% vs 38%, p<0.001) and lower left ventricular ejection fraction (45±9% vs 52±9%, p=0.043) compared with those with IMR≤31 and CFR>1.25, and lower left ventricular ejection fraction compared with patients with CFR≤1.25 and IMR≤31 (45±9% vs 54±7%, p=0.025). Infarct size and area at risk were larger in the former, compared with other groups. CONCLUSIONS: IMR and CFR are associated with the presence of microvascular obstruction in STEMI. Patients with an IMR>31 units and a CFR≤1.25 have higher prevalence of microvascular obstruction, lower left ventricular ejection fraction, larger infarct size and area at risk. TRIAL REGISTRATION NUMBER: NCT04677257.

Short-term air pollution exposure and mechanisms of plaque instability in acute coronary syndromes: An optical coherence tomography study.

BACKGROUND AND AIMS: Air pollution is emerging as an important risk factor for acute coronary syndrome (ACS). In this study, we investigated the association between short-term air pollution exposure and mechanisms of coronary plaque instability evaluated by optical coherence tomography (OCT) imaging in ACS patients. METHODS: Patients with ACS undergoing OCT imaging were retrospectively selected. Mechanism of culprit lesion instability was classified as plaque rupture (PR) or intact fibrous cap (IFC) by OCT. Based on each case's home address, the mean daily exposures to several pollutants, including particulate matter 2.5 (PM2.5), on the same day of ACS and in the immediate days (up to 6 days) prior to the index ACS, were collected. RESULTS: 139 ACS patients were included [69 (49.6%) had PR and 70 (50.4%) IFC]. Patients with PR, compared to those with IFC, had higher PM2.5 exposure levels on the same day of ACS, without differences in the immediate 6 days before index ACS. At multivariate analysis, PM2.5 exposure on the same day of ACS was the only independent predictor of PR [OR = 1.912 per SD (8.6 µg/m3), CI95 % (1.087-3.364), p = 0.025]. Patients with PR presented a steady increase in PM2.5 daily exposure levels in the days preceding the occurrence of ACS, with a peak the day of ACS (p for trend = 0.042) CONCLUSIONS: This study demonstrates for the first time that a higher short-term PM2.5 exposure, on the same day of ACS, is associated with an increased risk of PR as a pathobiological mechanism of coronary plaque instability.

Immediate versus staged complete revascularization in acute coronary syndrome: A meta-analysis of randomized controlled trials.

BACKGROUND: Clinical guidelines recommend a complete revascularization (CR) in patients with acute coronary syndromes (ACS) and multivessel disease (MVD). However, its optimal timing is unclear. The aim of this meta-analysis was to compare the clinical outcomes following immediate versus staged CR in ACS. METHODS: PubMed and Scopus were searched until March 2023 for randomized controlled trials (RCTs) comparing immediate versus staged CR. The primary endpoint was major adverse cardiovascular event (MACE) at the longest follow-up. Secondary outcomes were all-cause death, cardiovascular death, myocardial infarction (MI), any unplanned revascularization, target-vessel revascularization (TVR), and stent thrombosis. Safety outcomes were major bleeding, contrast volume, procedure duration, and length of hospitalization. RESULTS: Eight RCTs were included (3559 patients, weighted mean follow-up 12.5 months). There were no differences in the primary endpoint (OR 0.74, 95%CI: 0.54-1.01) and in the secondary endpoints of death, and stent thrombosis between the two CR strategies. Immediate CR was associated with a lower risk of recurrent MI (OR 0.51, 95% CI 0.34-0.76), any unplanned revascularization (OR 0.59, 95%CI: 0.43-0.80), and TVR (OR 0.61, 95% CI 0.45-0.84) compared to staged CR. Immediate CR was also associated with lower total contrast volume and shorter total procedure duration and hospitalization length compared to staged CR without differences in major bleedings. CONCLUSION: No difference was found between immediate and staged CR regarding MACE, or deaths rates at one year. Immediate CR may be associated with a lower risk of recurrent MI and unplanned coronary revascularization than staged CR.

[Myocardial infarction with non-obstructive coronary artery disease: diagnostic work-up in the catheterization laboratory]. / L'infarto miocardico in assenza di coronaropatia ostruttiva: work-up diagnostico nel laboratorio di Emodinamica.

Myocardial infarction with non-obstructive coronary artery disease (MINOCA) is a heterogeneous clinical condition affecting 5% to 8% of patients presenting with acute myocardial infarction. Initially it was considered a favorable clinical diagnosis, nowadays it is known that MINOCA can significantly affect patient quality of life and portends a guarded prognosis. Therefore, it is of utmost importance to identify the specific pathophysiological mechanism underlying this clinical condition in order to set up a targeted pharmacological and non-pharmacological therapy. Coronary angiography is still a mandatory diagnostic test to rule out obstructive coronary artery disease but has limited capability to identify other potential functional and structural etiologies of MINOCA. The purpose of this review is to provide an overview of the invasive diagnostic work-up of patients with MINOCA, highlighting the diagnostic tools warranted beyond coronary angiography inside the cath lab (intracoronary provocation tests, intracoronary imaging and indexes for the assessment of coronary microvascular dysfunction), and the remaining essential knowledge gaps in this field.

Microvascular Complications Are Associated With Coronary Collateralization in Type 2 Diabetes and Chronic Occlusion.

CONTEXT: Coronary collateral (CC) vessel development appears to be protective with regard to adverse cardiovascular events and survival in patients with coronary chronic total occlusion (CTO). The influence of type 2 diabetes mellitus (T2DM) on CC growth has been controversial. In particular, the role of diabetic microvascular complications (DMC) in determining coronary collateralization has not been elucidated. OBJECTIVE: To investigate whether patients with DMC presented differences in CC vessel presence and grading as compared with patients without DMC. METHODS: We conducted a single-center observational study, including consecutive T2DM patients, without previous cardiovascular history, undergoing a clinically indicated coronary angiography for chronic coronary syndrome (CCS) and angiographic evidence of at least one CTO. Patients were subdivided into 2 study groups according to the presence/absence of at least one DMC (neuropathy, nephropathy, or retinopathy). The presence and grading of angiographically visible CC development from the patent vessels to the occluded artery were assessed using the Rentrop classification. RESULTS: We enrolled 157 patients (mean age 68.6 ± 9.8 years; 120 [76.4%] men). Patients with DMC (75 [47.8%]) had a higher prevalence of CC (69 [92.0%] vs 62 [75.6%], P = .006) and high-grade CC (55 [73.3%] vs 39 [47.6%], P = .001) compared with those without, and we found a positive association between the number of DMC in each patient and the prevalence of high-grade CC. CONCLUSION: Among T2DM patients with coronary CTO, the presence of DMC was associated with a high CC development.

Relationship between stent length and very long-term target lesion failure following percutaneous coronary intervention for ST-elevation myocardial infarction in the drug-eluting stents era: insights from the EXAMINATION-EXTEND study.

BACKGROUND: Little data exist on the relationship between total stent length (TSL) and cardiovascular outcomes at very-long follow-up in patients with ST-elevation myocardial infarction (STEMI) in the 2nd generation drug-eluting stents (DES) era. AIM: To analyze the relationship between TSL and 10-year target-lesion failure (TLF) in STEMI patients treated with percutaneous coronary intervention enrolled in the EXAMINATION-EXTEND. METHODS: The EXAMINATION-EXTEND was an extended-follow-up study of the EXAMINATION trial, which randomized 1:1 STEMI patients to receive DES or bare metal stent (BMS). The primary endpoint was TLF, defined as a composite of target lesion revascularization (TLR), target vessel myocardial infarction (TVMI), or definite/probable stent thrombosis (ST). Relationship between stent length and TLF was evaluated in the whole study group in a multiple-adjusted Cox regression model with TSL as a quantitative variable. Subgroup analysis was also performed according to stent type, diameter, and overlap. RESULTS: A total of 1,489 patients with a median TSL of 23 mm (Q1-Q318-35 mm) were included. TSL was associated with TLF at 10 years (adjusted HR per 5 mm increase of 1.07; 95% CI, 1.01-1.14; P = .02). This effect was mainly driven by TLR and was consistent regardless of stent type, diameter, or overlap. There was no significant relationship between TSL and TV-MI or ST. CONCLUSIONS: In STEMI patients, there is a direct relationship between TSL implanted in the culprit vessel and the risk of TLF at 10 years, mainly driven by TLR. The use of DES did not modify this association.

MINOCA Associated with a Myocardial Bridge: Pathogenesis, Diagnosis and Treatment.

Myocardial bridging (MB) is the most frequent congenital coronary anomaly characterized by a segment of an epicardial coronary artery that passes through the myocardium. MB is an important cause of myocardial ischemia and is also emerging as a possible cause of myocardial infarction with non-obstructed coronary arteries (MINOCA). There are multiple mechanisms underlying MINOCA in patients with MB (i.e., MB-mediated increased risk of epicardial or microvascular coronary spasm, atherosclerotic plaque disruption and spontaneous coronary artery dissection). The identification of the exact pathogenetic mechanism is crucial in order to establish a patient-tailored therapy. This review provides the most up-to-date evidence regarding the pathophysiology of MINOCA in patients with MB. Moreover, it focuses on the available diagnostic tools that could be implemented at the time of coronary angiography to achieve a pathophysiologic diagnosis. Finally, it focuses on the therapeutic implications associated with the different pathogenetic mechanisms of MINOCA in patients with MB.

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Non-ST-Elevation Coronary Syndromes and Multivessel Disease: A Systematic Review and Meta-Analysis.

There is lack of evidence regarding the optimal revascularization strategy in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) and multivessel disease (MVD). This systematic review and meta-analysis compares the clinical impact of percutaneous coronary intervention (PCI) with that of coronary artery bypass graft surgery (CABG) in this subset of patients. EMBASE, MEDLINE, and Web of Knowledge were searched for studies including patients with NSTE-ACS and MVD who underwent PCI or CABG up to September 1, 2021. The primary end point of the meta-analysis was all-cause mortality at 1 year. The secondary end points were myocardial infarction (MI), stroke, or repeat revascularization at 1 year. The analysis was conducted using the Mantel-Haenszel random-effects model to calculate the odds ratio (OR) with 95% confidence interval (CI). Four prospective observational studies met the inclusion criteria, including 1,542 patients who underwent CABG and 1,630 patients who underwent PCI. No significant differences were found in terms of all-cause mortality (OR 0.91, 95% CI 0.68 to 1.21, p = 0.51), MI (OR 0.78, 95% CI 0.40 to 1.51, p = 0.46), or stroke (OR 1.54, 95% CI 0.55 to 4.35, p = 0.42) between PCI and CABG. Repeat revascularization was significantly lower in the CABG group (OR 0.21, 95% CI 0.13 to 0.34, p <0.00001). In patients presenting with NSTE-ACS and MVD, 1-year mortality, MI, and stroke were similar between patients treated with either PCI or CABG, but the repeat revascularization rate was higher after PCI.

Impact of air pollution on ischemic heart disease: Evidence, mechanisms, clinical perspectives.

Ambient air pollution, and especially particulate matter (PM) air pollution <2.5 µm in diameter (PM2.5), has clearly emerged as an important yet often overlooked risk factor for atherosclerosis and ischemic heart disease (IHD). In this review, we examine the available evidence demonstrating how acute and chronic PM2.5 exposure clinically translates into a heightened coronary atherosclerotic burden and an increased risk of acute ischemic coronary events. Moreover, we provide insights into the pathophysiologic mechanisms underlying PM2.5-mediated atherosclerosis, focusing on the specific biological mechanism through which PM2.5 exerts its detrimental effects. Further, we discuss about the possible mechanisms that explain the recent findings reporting a strong association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, increased PM2.5 exposure, and morbidity and mortality from IHD. We also address the possible mitigation strategies that should be implemented to reduce the impact of PM2.5 on cardiovascular morbidity and mortality, and underscoring the strong need of clinical trials demonstrating the efficacy of specific interventions (including both PM2.5 reduction and/or specific drugs) in reducing the incidence of IHD. Finally, we introduce the emerging concept of the exposome, highlighting the close relationship between PM2.5 and other environmental exposures (i.e.: traffic noise and climate change) in terms of common underlying pathophysiologic mechanisms and possible mitigation strategies.

Myocardial Injury Portends a Higher Risk of Mortality and Long-Term Cardiovascular Sequelae after Hospital Discharge in COVID-19 Survivors.

Background: Cardiovascular sequelae after COVID-19 are frequent. However, the predictors for their occurrence are still unknown. In this study, we aimed to assess whether myocardial injury during COVID-19 hospitalization is associated to CV sequelae and death after hospital discharge. Methods: In this prospective observational study, consecutive patients who were admitted for COVID-19 in a metropolitan COVID-19 hub in Italy, between March 2021 and January 2022, with a ≥ 1 assessment of high sensitivity cardiac troponin I (hs-cTnI) were included in the study, if they were alive at hospital discharge. Myocardial injury was defined as elevation hs-cTnI > 99th percentile of the upper reference limit. The incidence of all-cause mortality and major adverse cardiovascular and cerebrovascular events (MACCE, including cardiovascular death, admission for acute or chronic coronary syndrome, hospitalization for heart failure, and stroke/transient ischemic attack) at follow-up were the primary outcomes. Arrhythmias, inflammatory heart diseases, and/or thrombotic disorders were analyzed as well. Results: Among the 701 COVID-19 survivors (mean age 66.4 ± 14.4 years, 40.2% female), myocardial injury occurred in 75 (10.7%) patients. At a median follow-up of 270 days (IQR 165, 380), all-cause mortality (21.3% vs. 6.1%, p < 0.001), MACCE (25.3% vs. 4.5%, p < 0.001), arrhythmias (9.3% vs. 5.0%, p = 0.034), and inflammatory heart disease (8.0% vs. 1.1%, p < 0.001) were more frequent in patients with myocardial injury compared to those without. At multivariate analysis, myocardial injury (HR 1.95 [95% CI:1.05−3.61]), age (HR 1.09 [95% CI:1.06−1.12]), and chronic kidney disease (HR 2.63 [95% CI:1.33−5.21]) were independent predictors of death. Myocardial injury (HR 3.92 [95% CI:2.07−7.42]), age (HR 1.05 [95% CI:1.02−1.08]), and diabetes (HR 2.35 [95% CI:1.25−4.43]) were independent predictors of MACCE. Conclusion: In COVID-19 survivors, myocardial injury during the hospital stay portends a higher risk of mortality and cardiovascular sequelae and could be considered for the risk stratification of COVID-19 sequelae in patients who are successfully discharged.

Microvascular complications identify a specific coronary atherosclerotic phenotype in patients with type 2 diabetes mellitus.

BACKGROUND: Patients with type 2 diabetes mellitus (T2DM) are considered as a homogeneous cohort of patients. However, the specific role of diabetic microvascular complications (DMC), in determining the features of coronary plaques is poorly known. We investigated whether the presence of DMC may identify a different phenotype of patients associated to specific clinical, angiographic, optical coherence tomography (OCT) features and different prognosis. METHODS: We prospectively enrolled consecutive T2DM patients with obstructive coronary artery disease (CAD) at their first coronary event. Patients were stratified according to the presence or absence of DMC, including diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy. OCT assessment of the culprit vessel was performed in a subgroup of patients. The incidence of major adverse cardiac events (MACEs) was assessed at follow-up. RESULTS: We enrolled 320 T2DM patients (mean age 70.3 ± 8.8 years; 234 [73.1%] men, 40% acute coronary syndrome, 60% chronic coronary syndrome). Patients with DMC (172 [53.75%]) presented a different clinical and biochemical profile and, of importance, a higher prevalence of multivessel CAD (109 [63.4%] vs. 68 [45.9%], p = 0.002). At OCT analysis, DMC was associated to a higher prevalence of large calcifications and healed plaques and to a lower prevalence of lipid plaques. Finally, MACEs rate was significantly higher (25 [14.5%] vs. 12 [8.1%], p = 0.007) in DMC patients, mainly driven by a higher rate of planned revascularizations, and DMC predicted the occurrence of MACEs (mean follow-up 33.4 ± 15.6 months). CONCLUSIONS: The presence of DMC identifies a distinct diabetic population with more severe CAD but with a more stable pattern of coronary atherosclerosis.

Myocardial infarction with nonobstructive coronary arteries: the need for precision medicine.

PURPOSE OF REVIEW: Myocardial infarction with nonobstructive coronary arteries (MINOCA) represents about 6-8% of all patients with myocardial infarction (MI), and several pathophysiological mechanisms showed to be involved in this heterogeneous clinical condition. Of note, MINOCA proved to be associated with a significant risk of mortality, angina burden and socioeconomic costs. RECENT FINDINGS: Results from randomized clinical trials evaluating the clinical effectiveness of a comprehensive diagnostic algorithm, along with the acute and long-term management of patients with MINOCA, are pending. SUMMARY: In this review article, we aim at providing an overview of the clinical features, diagnostic work-up and the therapeutic management of patients presenting with MINOCA, highlighting the recent acquisition along with the remaining important knowledge gaps in this field.