[Ten questions about myocardial infarction with non-obstructed coronary arteries]. / Dieci quesiti in tema di infarto miocardico in assenza di coronaropatia ostruttiva.

The term "MINOCA" refers to myocardial infarction with non-obstructed coronary arteries and has been used to define acute myocardial infarction with no angiographic evidence of significant epicardial coronary artery stenosis. Patients with MINOCA represent a rather heterogeneous group of acute coronary syndrome, and this may account for the wide variation in the incidence of MINOCA in different studies. Several pathogenic mechanisms have been suggested to underlie MINOCA, but the condition continues to represent a diagnostic and therapeutic challenge for the cardiologist. Therefore, an adequate diagnostic assessment, carefully characterizing the pathogenic mechanisms, and a selection of more targeted treatments are needed to improve clinical outcomes. In this focused review, we will try to provide answers to the most common questions on the causes, diagnosis, treatment, and outcomes of MINOCA.

Cardiac Magnetic Resonance to Predict Cardiac Mass Malignancy: The CMR Mass Score.

BACKGROUND: Multimodality imaging is currently suggested for the noninvasive diagnosis of cardiac masses. The identification of cardiac masses' malignant nature is essential to guide proper treatment. We aimed to develop a cardiac magnetic resonance (CMR)-derived model including mass localization, morphology, and tissue characterization to predict malignancy (with histology as gold standard), to compare its accuracy versus the diagnostic echocardiographic mass score, and to evaluate its prognostic ability. METHODS: Observational cohort study of 167 consecutive patients undergoing comprehensive echocardiogram and CMR within 1-month time interval for suspected cardiac mass. A definitive diagnosis was achieved by histological examination or, in the case of cardiac thrombi, by histology or radiological resolution after adequate anticoagulation treatment. Logistic regression was performed to assess CMR-derived independent predictors of malignancy, which were included in a predictive model to derive the CMR mass score. Kaplan-Meier curves and Cox regression were used to investigate the prognostic ability of predictors. RESULTS: In CMR, mass morphological features (non-left localization, sessile, polylobate, inhomogeneity, infiltration, and pericardial effusion) and mass tissue characterization features (first-pass perfusion and heterogeneity enhancement) were independent predictors of malignancy. The CMR mass score (range, 0-8 and cutoff, ≥5), including sessile appearance, polylobate shape, infiltration, pericardial effusion, first-pass contrast perfusion, and heterogeneity enhancement, showed excellent accuracy in predicting malignancy (areas under the curve, 0.976 [95% CI, 0.96-0.99]), significantly higher than diagnostic echocardiographic mass score (areas under the curve, 0.932; P=0.040). The agreement between the diagnostic echocardiographic mass and CMR mass scores was good (κ=0.66). A CMR mass score of ≥5 predicted a higher risk of all-cause death (P<0.001; hazard ratio, 5.70) at follow-up. CONCLUSIONS: A CMR-derived model, including mass morphology and tissue characterization, showed excellent accuracy, superior to echocardiography, in predicting cardiac masses malignancy, with prognostic implications.

Predictors of adverse cardiac events of coronary myocardial bridging diagnosed with computed tomography angiography.

AIMS: Myocardial bridging (MB) is a frequent congenital anomaly of the epicardial coronary arteries commonly considered a benign condition. However, in some cases a complex interplay between anatomical, clinical and physiology factors may lead to adverse events, including sudden cardiac death. Coronary CT angiography (CCTA) emerged as the gold standard noninvasive imaging technique for the evaluation of MB. Aim of the study was to evaluate MB prevalence and anatomical features in a large population of patients who underwent CCTA for suspected CAD and to identify potential anatomical and clinical predictors of adverse cardiac events at long-term follow-up. METHODS AND RESULTS: Two-hundred and six patients (mean age 60.3 ± 11.8 years, 128 male) with MB diagnosed at CCTA were considered. A long MB was defined as ≥25 mm of overlying myocardium, whereas a deep MB as ≥2 mm of overlying myocardium. The study endpoint was the sum of the following adverse events: cardiac death, bridge-related acute coronary syndrome, hospitalization for angina or bridge-related ventricular arrhythmias and MB surgical treatment. Of the 206 patients enrolled in the study, 9 were lost to follow-up, whereas 197 (95.6%) had complete follow-up (mean 7.01 ± 3.0 years) and formed the analytic population. Nineteen bridge-related events occurred in 18 patients (acute coronary syndrome in 7, MB surgical treatment in 2 and hospitalization for bridge-related events in 10). Typical angina at the time of diagnosis and long MB resulted as significant independent predictors of adverse outcome. CONCLUSIONS: Typical angina and MB length ≥ 25 mm were independent predictors of cardiac events.

Microplastics and Nanoplastics in Atheromas and Cardiovascular Events.

BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. METHODS: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. RESULTS: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 µg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 µg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). CONCLUSIONS: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).

Myocardial sodium-glucose cotransporter 2 expression and cardiac remodelling in patients with severe aortic stenosis: The BIO-AS study.

AIM: Cardiac remodelling plays a major role in the prognosis of patients with aortic stenosis (AS) and could impact the benefits of aortic valve replacement. Our study aimed to evaluate the expression of sodium-glucose cotransporter 2 (SGLT2) gene and protein in patients with severe AS stratified in high gradient (HG) and low flow-low gradient (LF-LG) AS and its association with cardiac functional impairments. METHODS AND RESULTS: Gene expression and protein levels of main biomarkers of cardiac fibrosis (galectin-3, sST2, serpin-4, procollagen type I amino-terminal peptide, procollagen type I carboxy-terminal propeptide, collagen, transforming growth factor [TGF]-ß), inflammation (growth differentiation factor-15, interleukin-6, nuclear factor-κB [NF-κB]), oxidative stress (superoxide dismutase 1 [SOD1] and 2 [SOD2]), and cardiac metabolism (sodium-hydrogen exchanger, peroxisome proliferator-activated receptor [PPAR]-α, PPAR-γ, glucose transporter 1 [GLUT1] and 4 [GLUT4]) were evaluated in blood samples and heart biopsies of 45 patients with AS. Our study showed SGLT2 gene and protein hyper-expression in patients with LF-LG AS, compared to controls and HG AS (p < 0.05). These differences remained significant even after adjusting for age, gender, body mass index, history of diabetes mellitus, arterial hypertension, and coronary artery disease. SGLT2 gene expression was positively correlated with: (i) TGF-ß (r = 0.72, p < 0.001) and collagen (r = 0.73, p < 0.001) as markers of fibrosis; (ii) NF-κB (r = 0.36, p < 0.01) and myocardial interleukin-6 (r = 0.68, p < 0.001) as markers of inflammation: (iii) SOD2 (r = -0.38, p < 0.006) as a marker of oxidative stress; (iv) GLUT4 (r = 0.33, p < 0.02) and PPAR-α (r = 0.36, p < 0.01) as markers of cardiac metabolism. CONCLUSION: In patients with LF-LG AS, SGLT2 gene and protein were hyper-expressed in cardiomyocytes and associated with myocardial fibrosis, inflammation, and oxidative stress.

Predictors of percutaneous coronary intervention derived from CCTA in patients with chronic coronary syndrome.

BACKGROUND: To identify anatomical and morphological plaque features predictors of PCI and create a multiparametric score to increase the predictive yield. Moreover, we assessed the incremental predictive value of FFRCT (Fractional Flow Reserve derived from CCTA) trans-lesion gradient (ΔFFRCT) when integrated into the score. METHODS: Observational cohort study including patients undergoing CCTA for suspected coronary artery disease, with FFRCT available, referred to invasive coronary angiogram and assessment of fractional flow reserve. Plaque analysis was performed using validated semi-automated software. Logistic regression was performed to identify anatomical and morphological plaque features predictive of PCI. Optimal thresholds were defined by area under the receiver-operating characteristics curve (AUC) analysis. A scoring system was developed in a derivation cohort (70 â€‹% of the study population) and tested in a validation cohort (30 â€‹% of patients). RESULTS: The overall study population included 340 patients (455 vessels), among which 238 patients (320 vessels) were included in the derivation cohort. At multivariate logistic regression analysis, absence of left main disease, diameter stenosis (DS), non-calcified plaque (NCP) volume, and percent atheroma volume (PAV) were independent predictors of PCI. Optimal thresholds were: DS â€‹≥ â€‹50 â€‹%, volume of NCP>113 â€‹mm3 and PAV>17 â€‹%. A weighted score (CT-PCI Score) ranging from 0 to 11 was obtained. The AUC of the score was 0.80 (95%CI 0.74-0.86). The integration of ΔFFRCT in the CT-PCI score led to a mild albeit not significant increase in the AUC (0.82, 95%CI 0.77-0.87, p â€‹= â€‹0.328). CONCLUSIONS: Plaque anatomy and morphology derived from CCTA could aid in identifying patients amenable to PCI.

Post-cardiac injury syndrome and pericardial effusion recurrence after pericardial effusion drainage in chronic idiopathic pericardial effusion.

INTRODUCTION: The management of even large pericardial effusions in asymptomatic patients is still a matter of debate. Aim of the present study is to explore, in a multicenter setting, the rate of post-cardiac injury syndromes (PCIS) and pericardial effusion recurrence after pericardial effusion drainage procedure. MATERIAL AND METHODS: This is a multicenter international retrospective study including a consecutive cohort of patients diagnosed with large, chronic and idiopathic pericardial effusions, prospectively evaluated from January 2003 to December 2021 who underwent a clinically indicated pericardial drainage procedure. Two separate end-points were recorded: 1) recurrence of pericardial effusion after drainage without any sign of pericardial inflammation 2) occurrence of PCIS, defined as the new onset of pericarditis 1 to 6 weeks after pericardial intervention. RESULTS: 124 patients were enrolled (50 % female, mean age 64 years old). A mean follow-up of 29.6 ± 25.6 months was obtained in 110 patients (88 %). 110 patients were treated with pericardiocentesis (89 %), 25 with pleuro-pericardial windows (20 %), and 1 with pericardiectomy (1 %). PCIS occurred in 21 out of 124 patients followed for at least 6 weeks (16.9%). Recurrence of pericardial effusion after drainage without any sign of pericardial inflammation occurred in 68 out of 110 patients at a longer follow-up (61.8 %). At multivariate analysis only inflammatory cells in pericardial fluid was associated with PCIS and pericardiocentesis with pericardial effusion recurrency. CONCLUSION: Our data support the need of caution with the use of pericardiocentesis in asymptomatic patients with large pericardial effusion as it is often associated with pericardial effusion recurrence. Of interest the presence of inflammatory cells in the pericardial fluid is associated with PCIS after pericardial drainage procedures.

Prognostic Role of Early Cardiac Magnetic Resonance in Myocardial Infarction With Nonobstructive Coronary Arteries.

BACKGROUND: Cardiac magnetic resonance (CMR) plays a pivotal diagnostic role in myocardial infarction with nonobstructive coronary arteries (MINOCA). To date, a prognostic stratification of these patients is still lacking. OBJECTIVES: This study aims to assess the prognostic role of CMR in MINOCA. METHODS: The authors assessed 437 MINOCA from January 2017 to October 2021. They excluded acute myocarditis, takotsubo syndromes, cardiomyopathies, and other nonischemic etiologies. Patients were classified into 3 subgroups according to the CMR phenotype: 1) presence of late gadolinium enhancement (LGE) and abnormal mapping (M) values (LGE+/M+); 2) regional ischemic injury with abnormal mapping and no LGE (LGE-/M+); and 3) nonpathological CMRs (LGE-/M-). The primary outcome was the presence of major adverse cardiovascular events (MACE). The mean follow-up was 33.7 ± 12.0 months and CMR was performed on average at 4.8 ± 1.5 days from the acute presentation. RESULTS: The final cohort included 198 MINOCA; 116 (58.6%) comprised the LGE+/M+ group. During follow-up, MACE occurred significantly more frequently in MINOCA LGE+/M+ than in the LGE+/M- and normal-CMR (LGE-/M-) subgroups (20.7% vs 6.7% and 2.7%; P = 0.006). The extension of myocardial damage at CMR was significantly greater in patients who developed MACE. In multivariable Cox regression, %LGE was an independent predictor of MACE (HR: 1.123 [95% CI: 1.064-1.185]; P < 0.001) together with T2 mapping values (HR: 1.190 [95% CI: 1.145-1.237]; P = 0.001). CONCLUSIONS: In MINOCA with early CMR execution, the %LGE and abnormal T2 mapping values were identified as independent predictors of adverse cardiac events at ∼3.0 years of follow-up. These parameters can be considered as high-risk markers in MINOCA.

Characterisation of coronary microvascular dysfunction in patients with severe aortic stenosis undergoing TAVI.

BACKGROUND: Microvascular resistance reserve (MRR) is a validated measure of coronary microvascular function independent of epicardial resistances. AIMS: We sought to assess whether MRR is associated with adverse cardiac remodelling, a low-flow phenotype and extravalvular cardiac damage (EVCD) in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). METHODS: Invasive thermodilution-based assessment of the coronary microvascular function of the left anterior descending artery was performed in a prospective, multicentre cohort of patients undergoing TAVI. Coronary microvascular dysfunction (CMD) was defined as the lowest MRR tertile of the study cohort. Haemodynamic measurements were performed at baseline and then repeated immediately after TAVI. EVCD and markers of a low-flow phenotype were assessed with echocardiography. RESULTS: A total of 134 patients were included in this study. Patients with low MRR were more frequently females, had a lower estimated glomerular filtration rate and a higher rate of atrial fibrillation. MRR was significantly lower in patients with advanced EVCD (median 1.80 [1.26-3.30] vs 2.50 [1.87-3.41]; p=0.038) and in low-flow, low-gradient AS (LF LG-AS) (median 1.85 [1.20-3.04] vs 2.50 [1.87-3.40]; p=0.008). Overall, coronary microvascular function tended to improve after TAVI and, in particular, MRR increased significantly after TAVI in the subgroup with low MRR at baseline. However, MRR was significantly impaired in 38 (28.4%) patients immediately after TAVI. Advanced EVCD (adjusted odds ratio 3.08 [1.22-7.76]; p=0.017) and a low-flow phenotype (adjusted odds ratio 3.36 [1.08-10.47]; p=0.036) were significant predictors of CMD. CONCLUSIONS: In this observational, hypothesis-generating study, CMD was associated with extravalvular cardiac damage and a low-flow phenotype in patients with severe AS undergoing TAVI.

Impact of coronary CT image quality on the accuracy of the FFRCT Planner.

OBJECTIVE: To assess the accuracy of a virtual stenting tool based on coronary CT angiography (CCTA) and fractional flow reserve (FFR) derived from CCTA (FFRCT Planner) across different levels of image quality. MATERIALS AND METHODS: Prospective, multicenter, single-arm study of patients with chronic coronary syndromes and lesions with FFR ≤ 0.80. All patients underwent CCTA performed with recent-generation scanners. CCTA image quality was adjudicated using the four-point Likert scale at a per-vessel level by an independent committee blinded to the FFRCT Planner. Patient- and technical-related factors that could affect the FFRCT Planner accuracy were evaluated. The FFRCT Planner was applied mirroring percutaneous coronary intervention (PCI) to determine the agreement with invasively measured post-PCI FFR. RESULTS: Overall, 120 patients (123 vessels) were included. Invasive post-PCI FFR was 0.88 ± 0.06 and Planner FFRCT was 0.86 ± 0.06 (mean difference 0.02 FFR units, the lower limit of agreement (LLA) - 0.12, upper limit of agreement (ULA) 0.15). CCTA image quality was assessed as excellent (Likert score 4) in 48.3%, good (Likert score 3) in 45%, and sufficient (Likert score 2) in 6.7% of patients. The FFRCT Planner was accurate across different levels of image quality with a mean difference between FFRCT Planner and invasive post-PCI FFR of 0.02 ± 0.07 in Likert score 4, 0.02 ± 0.07 in Likert score 3 and 0.03 ± 0.08 in Likert score 2, p = 0.695. Nitrate dose ≥ 0.8mg was the only independent factor associated with the accuracy of the FFRCT Planner (95%CI - 0.06 to - 0.001, p = 0.040). CONCLUSION: The FFRCT Planner was accurate in predicting post-PCI FFR independent of CCTA image quality. CLINICAL RELEVANCE STATEMENT: Being accurate in predicting post-PCI FFR across a wide spectrum of CT image quality, the FFRCT Planner could potentially enhance and guide the invasive treatment. Adequate vasodilation during CT acquisition is relevant to improve the accuracy of the FFRCT Planner. KEY POINTS: • The fractional flow reserve derived from coronary CT angiography (FFRCT) Planner is a novel tool able to accurately predict fractional flow reserve after percutaneous coronary intervention. • The accuracy of the FFRCT Planner was confirmed across a wide spectrum of CT image quality. Nitrates dose at CT acquisition was the only independent predictor of its accuracy. • The FFRCT Planner could potentially enhance and guide the invasive treatment.

Combined Cardiac Damage Staging by Echocardiography and Cardiac Catheterization in Patients With Clinically Significant Aortic Stenosis.

BACKGROUND: Cardiac damage (CD) staging enhances risk stratification in patients with clinically significant aortic stenosis (AS). We aimed to assess the prognostic value and reclassification rate of right heart catheterization (RHC) compared with transthoracic echocardiography (TTE) in characterising CD staging at 3-year follow-up in patients with clinically significant AS, to identify patients that would benefit from RHC for prognostic stratification, and to test the prognostic value of combined CD staging. METHODS: An observational cohort study of 432 AS patients undergoing TTE and RHC were divided into moderate or asymptomatic severe (m/asAS) and symptomatic severe (ssAS) AS. Kaplan-Meier curves were used to compare survival. The accuracy in prognostic stratification was tested by area under the receiver operating characteristic curve analysis and Delong test. RESULTS: In both cohorts, TTE- and RHC-derived staging systems had prognostic value, although the agreement between them appeared moderate. A higher proportion of patients were assigned to stage 2 by TTE than by RHC. Patients in TTE-derived stage 2 had a high reclassification rate, with 40%-50% presenting with right chamber involvement (stages 3-4) according to RHC. Discordant cases were significantly older, with higher prevalence of atrial fibrillation, markedly elevated N-terminal pro-B-type natriuretic peptide, and higher indexed left atrial volume, E/e', and systolic pulmonary artery pressure vs concordant cases (P < 0.05). The combined CD staging, integrating TTE and RHC, was more accurate in predicting mortality than the TTE-derived system (P < 0.05). CONCLUSIONS: In patients with m/asAS and ssAS, the combined CD staging, derived from TTE and RHC, was more accurate in predicting mortality than TTE alone. In a subset of AS patients, the integration of RHC may significantly improve prognostic stratification.

Coronary Microvascular Dysfunction in Patients With Heart Failure: Characterization of Patterns in HFrEF Versus HFpEF.

BACKGROUND: Coronary microvascular dysfunction (CMD) is involved in heart failure (HF) onset and progression, independently of HF phenotype and obstructive coronary artery disease. Invasive assessment of CMD might provide insights into phenotyping and prognosis of patients with HF. We aimed to assess absolute coronary flow, absolute microvascular resistance, myocardial perfusion, coronary flow reserve, and microvascular resistance reserve in patients with HF with preserved ejection fraction and HF with reduced ejection fraction (HFrEF). METHODS: Single-center, prospective study of 56 consecutive patients with de novo HF with nonobstructive coronary artery disease divided into HF with preserved ejection fraction (n=21) and HFrEF (n=35). CMD was invasively assessed by continuous intracoronary thermodilution and defined as coronary flow reserve <2.5. Left ventricular and left anterior descending artery-related myocardial mass was quantified by echocardiography and coronary computed tomography angiography. Myocardial perfusion (mL/min per g) was calculated as the ratio between absolute coronary flow and left anterior descending artery-related mass. RESULTS: Patients with HFrEF showed a higher left ventricular and left anterior descending artery-related myocardial mass compared with HF with preserved ejection fraction (P<0.010). Overall, 52% of the study population had CMD, with a similar prevalence between the 2 groups. In HFrEF, CMD was characterized by lower absolute microvascular resistance and higher absolute coronary flow at rest (functional CMD; P=0.002). CMD was an independent predictor of a lower rate of left ventricular reverse remodeling at follow-up. In patients with HF with preserved ejection fraction, CMD was mainly due to higher absolute microvascular resistance and lower absolute coronary flow during hyperemia (structural CMD; P≤0.030). CONCLUSIONS: Continuous intracoronary thermodilution allows the definition and characterization of patterns with distinct CMD in patients with HF and could identify patients with HFrEF with a higher rate of left ventricular reverse remodeling at follow-up.

Contemporary Echocardiographic Evaluation of Mitral Regurgitation and Guidance for Percutaneous Mitral Valve Repair.

Mitral valve regurgitation (MR) is a multifaceted valvular heart disease. Echocardiography plays a central role in etiology assessment, severity quantification, treatment candidacy, outcome evaluation, and patient follow-up. In this review, we describe the comprehensive echocardiographic assessment of MR, including transthoracic (TTE) and transesophageal (TEE) approaches, 2D and 3D modalities, strain imaging, stress echocardiography, and artificial intelligence (AI) applications. Transcatheter edge-to-edge mitral valve repair (TEER) has been established as a key therapy for patients with severe, symptomatic MR and high surgical risk. TEER is performed under TEE guidance. We outline a practical overview of echocardiographic guidance on TEER.

Continuous vs Bolus Thermodilution to Assess Microvascular Resistance Reserve.

BACKGROUND: Coronary flow reserve (CFR) and microvascular resistance reserve (MRR) can, in principle, be derived by any method assessing coronary flow. OBJECTIVES: The aim of this study was to compare CFR and MRR as derived by continuous (CFRcont and MRRcont) and bolus thermodilution (CFRbolus and MRRbolus). METHODS: A total of 175 patients with chest pain and nonobstructive coronary artery disease were studied. Bolus and continuous thermodilution measurements were performed in the left anterior descending coronary artery. MRR was calculated as the ratio of CFR to fractional flow reserve and corrected for changes in systemic pressure. In 102 patients, bolus and continuous thermodilution measurements were performed in duplicate to assess test-retest reliability. RESULTS: Mean CFRbolus was higher than CFRcont (3.47 ± 1.42 and 2.67 ± 0.81 [P < 0.001], mean difference 0.80, upper limit of agreement 3.92, lower limit of agreement -2.32). Mean MRRbolus was also higher than MRRcont (4.40 ± 1.99 and 3.22 ± 1.02 [P < 0.001], mean difference 1.2, upper limit of agreement 5.08, lower limit of agreement -2.71). The correlation between CFR and MRR values obtained using both methods was significant but weak (CFR, r = 0.28 [95% CI: 0.14-0.41]; MRR, r = 0.26 [95% CI: 0.16-0.39]; P < 0.001 for both). The precision of both CFR and MRR was higher when assessed using continuous thermodilution compared with bolus thermodilution (repeatability coefficients of 0.89 and 2.79 for CFRcont and CFRbolus, respectively, and 1.01 and 3.05 for MRRcont and MRRbolus, respectively). CONCLUSIONS: Compared with bolus thermodilution, continuous thermodilution yields lower values of CFR and MRR accompanied by an almost 3-fold reduction of the variability in the measured results.

Characteristics of patients with recurrent acute myocardial infarction after MINOCA.

BACKGROUND: Myocardial infarction (MI) with non-obstructed coronary arteries (MINOCA) is an increasingly recognized condition with challenging management. Some MINOCA patients ultimately experience recurrent acute MI (re-AMI) during follow-up; however, clinical and angiographic factors predisposing to re-AMI are still poorly defined. METHODS: In this retrospective multicenter cohort study we enrolled consecutive patients fulfilling diagnostic criteria of MINOCA according to the IV universal definition of myocardial infarction; characteristics of patients experiencing re-AMI during the follow-up were compared to a group of MINOCA patients without re-AMI. RESULTS: 54 patients (mean age 66 ± 13) experienced a subsequent re-AMI after MINOCA and follow-up was available in 44 (81%). Compared to MINOCA patients without re-AMI (n = 695), on first invasive coronary angiography (ICA) MINOCA patients with re-AMI showed less frequent angiographically normal coronaries (37 versus 53%, p = 0.032) and had a higher prevalence of atherosclerosis involving 3 vessels or left main stem (17% versus 8%, p = 0.049). Twenty-four patients (44%) with re-AMI underwent a new ICA: 25% had normal coronary arteries, 12.5% had mild luminal irregularities (<30%), 20.8% had moderate coronary atherosclerosis (30-49%), and 41.7% showed obstructive coronary atherosclerosis (≥50% stenosis). Among patients undergoing new ICA, atherosclerosis progression was observed in 11 (45.8%), 37.5% received revascularization, only 4.5% had low-density lipoprotein cholesterol (LDL_C) under 55 mg/dL and 33% experienced a new cardiovascular disease (CVD) event (death, AMI, heart failure, stroke) at subsequent follow-up. CONCLUSIONS: In the present study, only a minority of MINOCA patients with re-AMI underwent a repeated ICA, nearly one out of two showed atherosclerosis progression, often requiring revascularization. Recommended LDL-C levels were achieved only in a minority of the cases, indicating a possible underestimation of CVD risk in this population.

[Periprocedural myocardial injury and infarction after myocardial revascularization: incidence, clinical features and prognosis]. / Infarto e danno miocardico periprocedurali dopo rivascolarizzazione miocardica: incidenza, implicazioni cliniche e prognosi.

Myocardial revascularization, either percutaneous or surgical, is the cornerstone of chronic and acute ischemic coronary artery disease therapy. Periprocedural myocardial injury and infarction are possible complications of these procedures. Several pathogenetic mechanisms have been proposed in the setting of percutaneous (distal embolism, vasospasm, obstruction of a minor vessel) or surgical revascularization (prolonged ischemic time, early graft failure, arrhythmia or severe hypotension during the procedure). High-sensitivity cardiac troponins have emerged as the recommended biomarkers due to their important prognostic implications. However, data regarding diagnostic criteria, management and prognostic implications of these complications are lacking. The present review aims to provide an overview regarding the possible diagnostic criteria, management and prognostic role of periprocedural myocardial injury and infarction.

Comprehensive invasive evaluation of coronary microcirculation in patients with Takotsubo syndrome.

BACKGROUND AND AIMS: The etiology and pathophysiology of Takotsubo syndrome (TTS) remain a matter of debate. In murine models of coronary microvascular dysfunction (CMD), abnormalities in myocardial perfusion led to the development of TTS. Importantly, TTS was reversible when normal perfusion was restored. However, in clinical practice, the assessment of coronary microcirculation in patients with TTS has primarily relied on non-invasive or indirect, angiography-derived methods. METHODS AND RESULTS: For the first time, we performed invasive microcirculatory assessment, by both validated techniques currently available in the catheterization laboratory, namely intracoronary bolus and continuous thermodilution, in patients with TTS, upon hospital admission and at short term follow-up. Our findings demonstrate that CMD was consistently present in all patients upon hospital admission, as assessed by both techniques. At a median follow-up of 3 months, after the recovery of left ventricular ejection fraction, two third of patients no longer exhibited CMD. CONCLUSIONS: These findings support the hypothesis that an acute and transient worsening in coronary microvascular function plays a pivotal role in the pathophysiology of TTS.

Association of Mild-to-Moderate Aortic Regurgitation With Outcomes in Heart Failure With Preserved Ejection Fraction.

OBJECTIVE: To assess aortic regurgitation (AR) prevalence, its hemodynamic effect, and long-term prognostic implications in patients admitted with de novo or worsened heart failure with preserved ejection fraction (HFpEF). METHODS: Consecutive patients hospitalized with de novo or worsened HFpEF between 2014 and 2020 were enrolled. Patients with more than moderate aortic and/or mitral valve disease were excluded. Based on the presence and degree of AR, patients were divided into those without AR, those with mild, and those with moderate AR. Data on cardiovascular death, heart failure (HF) rehospitalization, and their composite (major adverse cardiovascular events) were collected. RESULTS: The final study population consisted of 458 HFpEF patients: 156 (34.1%) with mild-AR, 153 (33.4%) with moderate-AR, and the remaining 149 (32.5%) with no AR. Mild-to-moderate AR patients were older, with larger left atrium-left ventricle (LV) volumes, greater LV mass index, higher filling pressure, and prevalence of diastolic dysfunction compared with the no-AR group (all P<.05). During 5-year follow-up, 113 patients died of cardiovascular causes, 124 patients were rehospitalized for HF, whereas 196 experienced the composite endpoint. Mild-to-moderate AR was identified as an independent predictor of all-cause death (HR, 1.62; 95% CI, 1.14 to 1.58; P=.04) and major adverse cardiovascular event occurrence (HR, 1.48; 95% CI, 1.05 to 2.09; P=.02). A total of 126 (35.5%) of 355 patients showed progression of AR at follow-up echocardiography. CONCLUSION: Mild-to-moderate AR is common among patients hospitalized for HFpEF. It is associated with adverse LV remodeling and worse long-term outcomes. These findings warrant further prospective studies addressing the importance of AR in prognostic stratification and exploring therapeutic strategies to mitigate its hemodynamic effect on HF.