Assessment of the Ischaemic Effects of Myocardial Bridge by Echocardiographic Exercise Stress Test.

Background: Detection of myocardial bridge (MB) at angiography suggests it has a role in ischaemic-related symptoms in patients with angina without obstructive coronary artery disease. However, evidence that MB may cause myocardial ischaemia is limited. Methods: We studied 41 patients with MB of the left anterior descending coronary artery and otherwise normal coronary arteries. Fourteen patients with normal coronary arteries and without MB served as controls. All subjects underwent a maximal treadmill exercise stress test (EST) under ECG monitoring. Standard and speckle-tracking echocardiography were performed at baseline and immediately after peak EST. Results: EST duration and peak heart rate and systolic pressure were similar in the two groups. A positive EST (ST-segment depression .1 mm) was found in 18 patients in the MB group (43.9%) and none in the control group (p=0.001). No abnormalities in both left ventricle systolic and diastolic function were found between the two groups in the standard echocardiographic evaluation. Global and segmental (anterior, inferior) longitudinal strain (LS) did not differ at baseline between the groups. There was a small increase in global LS during EST in MB patients but not in the control group (p=0.01). Similar trends were found for regional LSs, with differences being significant for the medium (p=0.028) and apical (p=0.032) anterior segments. No differences in echocardiographic parameters and both global and segmental LSs were observed between MB patients with ischaemic ECG changes during EST versus those without. Conclusion: Our findings do not support the notion that MB results in significant degrees of myocardial ischaemia during maximal myocardial work.

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.

Right ventricular strain in Fabry disease: Prognostic implications.

INTRODUCTION: Left ventricular (LV) hypertrophy is the main feature of cardiac involvement in Anderson-Fabry disease (FD), but the right ventricle (RV) is also frequently affected. Previous studies failed to demonstrate an independent association between conventional parameters of RV performance and outcomes in FD. Nevertheless, if RV free wall strain (RV-FWS), assessed by 2D speckle tracking analysis, may provide a better prognostication is currently unknown. METHODS: We retrospectively evaluated the association between RV-FWS and the occurrence of cardiovascular events in a cohort of 56 patients with FD. The study endpoint comprises cardiovascular mortality, severe heart failure symptoms, new-onset atrial fibrillation and major arrhythmias requiring device implantation. RESULTS: Reduced RV-FWS, defined by values lower than 23%, was found in 25 (45%) patients. During a median follow-up of 47 months, 16 (29%) patients met the study endpoint. A ROC-curve analysis confirmed the threshold of reduced RV-FWS (<23%) as the best cut-off for predicting cardiovascular events, but with a lower power compared to left-sided parameters. On univariable Cox regression analysis, RV-FWS, expressed as continuous variable, was significantly associated with the study endpoint (HR: 0.795, 95% CI: 0.710-0.889, p < 0.001). However, RV-FWS did not retain a significant association with outcomes, after adjustment for LV global longitudinal strain or indexed left atrial volume (p = 0.340 and p = 0.289 respectively). CONCLUSIONS: RV-FWS was not independently associated with the occurrence of cardiovascular events in FD, confirming previous observations that prognosis is mainly driven by the severity of LV cardiomyopathy.

Comparative analysis of right ventricular strain in Fabry cardiomyopathy and sarcomeric hypertrophic cardiomyopathy.

AIMS: To perform a comparative analysis of right ventricle (RV) myocardial mechanics, assessed by 2D speckle-tracking echocardiography (2D-STE), between patients with Fabry disease and patients with sarcomeric disease. METHODS AND RESULTS: Patients with Fabry cardiomyopathy (FC) (n = 28) were compared with patients with sarcomeric hypertrophic cardiomyopathy (HCM), matched for degree of left ventricle hypertrophy (LVH) and demographic characteristics (n = 112). In addition, patients with Fabry disease and no LVH [phenotype-negative carriers of pathogenic α-galactosidase gene mutations (GLA LVH-)] (n = 28) were compared with age and sex-matched carriers of sarcomeric gene mutations without LVH [Phenotype-negative carriers of pathogenic sarcomeric gene mutations (Sarc LVH-)] (n = 56). Standard echocardiography and 2D-STE were performed in all participants. Despite a subtle impairment of RV global longitudinal strain (RV-GLS) was common in both groups, patients with FC showed a more prominent reduction of RV free wall longitudinal strain (RV-FWS) and lower values of difference between RV-FWS and RV-GLS (ΔRV strain), in comparison to individuals with HCM (P < 0.001 and P = 0.002, respectively). RV-FWS and ΔRV strain demonstrated an independent and additive value in discriminating FC from HCM, over the presence of symmetric LVH, systolic anterior motion of the mitral valve and RV hypertrophy. Similar results were found in GLA LVH- patients: they had worse RV-FWS and lower values of ΔRV strain as compared to Sarc LVH- patients (both P < 0.001). CONCLUSION: Patients with FC show a specific pattern of RV myocardial mechanics, characterized by a larger impairment of RV-FWS and lower ΔRV strain in comparison to patients with HCM, which may be helpful in the differential diagnosis between these two diseases.

Prognostic Assessment of Early Repolarization/J Wave Electrocardiographic Pattern in Patients With Stable Ischemic Heart Disease.

Recent studies suggested that early repolarization (ER)/J wave at the electrocardiogram (ECG) is associated with increased risk of sudden death and ventricular arrhythmias in patients with acute myocardial infarction. In this study, we prospectively assessed whether ER/J wave has any long-term prognostic implications in patients with stable ischemic heart disease (IHD). We enrolled consecutive clinically stable patients with documented IHD, referred to undergo a routine ECG. ER (typical concave ST-segment elevation) and J wave were diagnosed according to prospectively defined criteria. The final population included 617 patients with documented IHD (455 men; age 68.1 ± 11 years). ER/J wave was found in 138 patients (22.4%), 13 of whom (2.1%) showed ER and 133 (21.6%) a J wave. At a follow-up of 8.1±2.9 years, 160 deaths occurred (25.9%), 60 (9.7%) attributed to cardiovascular causes. Total mortality was lower in patients with versus those without ER/J wave (18.8% vs 28.0%; hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.40 to 0.93, p = 0.02). The difference, however, was not significant after adjustment for confounding clinical variables (HR 0.78, 95% CI 0.51 to 1.19, p = 0.25). No significant difference was found in cardiovascular death between patients with (7.2%) and those without (10.4%) ER/J wave (adjusted HR 0.78, 95% CI 0.40 to 1.55, p = 0.48). Similar results were obtained for ER and J wave separately, and for ECG location of ER/J wave (inferior or lateral/precordial) and type of J wave (notched or slurred). The ER/J wave pattern at the ECG is not associated with increased risk of long-term mortality in clinically stable patients with a documented history of IHD.

Clinical features and outcomes of patients with stable or unstable chest pain and no-obstructive coronary artery disease.

Background: Coronary microvascular dysfunction can be responsible for both stable angina and acute coronary syndrome (ACS). There are scarce data, however, about comparisons of clinical characteristics and outcomes of these 2 groups of patients. Materials and methods: We studied 47 consecutive patients who underwent coronary angiography for angina syndromes and showed no obstructive stenosis. Patients were divided in 2 groups, according to their clinical presentation, i.e., stable angina (n = 21) or non-ST segment elevation ACS (NSTE-ACS; n = 26). An intracoronary acetylcholine (Ach) test was performed in 12 and 17 patients of the 2 groups, respectively. Angina status, assessed by Seattle Angina Questionnaire (SAQ), and clinical events were assessed after 1, 6, and 30 months. An exercise stress test was performed 1 month after discharge. Results: Clinical characteristics and exercise test results of the 2 groups were largely similar. Ach testing induced epicardial or microvascular spasm in 6 (50.0%) and 10 (58.8%) stable and NSTE-ACS patients, respectively (p = 0.72). Stable patients reported higher rates of angina, compared to NSTE-ACS patients, both at 1 (p = 0.04) and 30 months (81 vs. 50%, p = 0.036) of follow-up. SAQ scores were also lower in stable vs. NSTE-ACS patients. Ach testing results showed no association with clinical outcomes. Conclusion: Clinical characteristics and exercise and Ach testing results are similar in angina patients with no-obstructive coronary artery disease with a stable or NSTE-ACS presentation. Stable patients show a worse symptomatic outcome irrespective of Ach test results.

Role of continuous glucose monitoring in diabetic patients at high cardiovascular risk: an expert-based multidisciplinary Delphi consensus.

BACKGROUND: Continuous glucose monitoring (CGM) shows in more detail the glycaemic pattern of diabetic subjects and provides several new parameters ("glucometrics") to assess patients' glycaemia and consensually guide treatment. A better control of glucose levels might result in improvement of clinical outcome and reduce disease complications. This study aimed to gather an expert consensus on the clinical and prognostic use of CGM in diabetic patients at high cardiovascular risk or with heart disease. METHODS: A list of 22 statements concerning type of patients who can benefit from CGM, prognostic impact of CGM in diabetic patients with heart disease, CGM use during acute cardiovascular events and educational issues of CGM were developed. Using a two-round Delphi methodology, the survey was distributed online to 42 Italian experts (21 diabetologists and 21 cardiologists) who rated their level of agreement with each statement on a 5-point Likert scale. Consensus was predefined as more than 66% of the panel agreeing/disagreeing with any given statement. RESULTS: Forty experts (95%) answered the survey. Every statement achieved a positive consensus. In particular, the panel expressed the feeling that CGM can be prognostically relevant for every diabetic patient (70%) and that is clinically useful also in the management of those with type 2 diabetes not treated with insulin (87.5%). The assessment of time in range (TIR), glycaemic variability (GV) and hypoglycaemic/hyperglycaemic episodes were considered relevant in the management of diabetic patients with heart disease (92.5% for TIR, 95% for GV, 97.5% for time spent in hypoglycaemia) and can improve the prognosis of those with ischaemic heart disease (100% for hypoglycaemia, 90% for hyperglycaemia) or with heart failure (87.5% for hypoglycaemia, 85% for TIR, 87.5% for GV). The experts retained that CGM can be used and can impact the short- and long-term prognosis during an acute cardiovascular event. Lastly, CGM has a recognized educational role for diabetic subjects. CONCLUSIONS: According to this Delphi consensus, the clinical and prognostic use of CGM in diabetic patients at high cardiovascular risk is promising and deserves dedicated studies to confirm the experts' feelings.

Perspectives in noninvasive imaging for chronic coronary syndromes.

Both the latest European guidelines on chronic coronary syndromes and the American guidelines on chest pain have underlined the importance of noninvasive imaging to select patients to be referred to invasive angiography. Nevertheless, although coronary stenosis has long been considered the main determinant of inducible ischemia and symptoms, growing evidence has demonstrated the importance of other underlying mechanisms (e.g., vasospasm, microvascular disease, energetic inefficiency). The search for a pathophysiology-driven treatment of these patients has therefore emerged as an important objective of multimodality imaging, integrating "anatomical" and "functional" information. We here provide an up-to-date guide for the choice and the interpretation of the currently available noninvasive anatomical and/or functional tests, focusing on emerging techniques (e.g., coronary flow velocity reserve, stress-cardiac magnetic resonance, hybrid imaging, functional-coronary computed tomography angiography, etc.), which could provide deeper pathophysiological insights to refine diagnostic and therapeutic pathways in the next future.

Clinical outcomes of patients with coronary microvascular dysfunction in absence of obstructive coronary atherosclerosis.

Up to 50% of patients presenting with stable, mainly exercise-induced, chest pain and 10-20% of those admitted to hospital with chest pain suggesting an acute coronary syndrome show normal or near-normal coronary arteries at angiography. Coronary microvascular dysfunction (CMD) is a major cause of symptoms in these patients. However, controversial data exist about their prognosis. In this article, we critically review characteristics and results of the main studies that assessed clinical outcome of patients with angina chest pain and nonobstructive coronary artery disease presenting with either a stable angina pattern or an acute coronary syndrome. Published data indicate that the patients included in most studies are heterogeneous and a major determinant of clinical outcome is the presence of atherosclerotic, albeit not obstructive, coronary artery disease. Long-term prognosis seems instead excellent in patients with totally normal coronary arteries and a syndrome of CMD-related stable angina (microvascular angina). On the other hand, the prognostic impact of CMD in patients presenting with an acute coronary syndrome needs to be better assessed in future studies.

Right ventricle-pulmonary artery coupling in repaired tetralogy of Fallot with pulmonary regurgitation: Clinical implications.

BACKGROUND: Right ventricle-pulmonary artery (RV-PA) coupling is a strong prognostic marker in several clinical settings, but few studies have focused on its role in repaired tetralogy of Fallot (rToF) with pulmonary regurgitation. AIM: To assess whether differences exist in RV-PA coupling, estimated by echocardiography, between patients with rToF and pulmonary regurgitation with or without an indication for pulmonary valve replacement (PVR). METHODS: The study population included 40 patients with rToF, who were allocated to two groups: 20 with an indication for PVR (i-PVR group); and 20 without an indication for PVR (ni-PVR group). Forty healthy controls were also included. All subjects underwent echocardiography, and cardiac magnetic resonance (CMR) was available in 27/40 patients with rToF. RV-PA coupling was assessed by echocardiographic tricuspid annular plane systolic excursion/pulmonary arterial systolic pressure (TAPSE/PASP) and right ventricular stroke volume/right ventricular end-systolic volume (RVSV/RVESV) by CMR. RESULTS: TAPSE was similar in the i-PVR and ni-PVR groups (19.0±3.4 vs 18.8±2.7mm; P=0.97) whereas RV-PA coupling was significantly worse in the i-PVR group versus the ni-PVR group (TAPSE/PASP 0.8±0.3 vs 1.1±0.5mm/mmHg; P=0.001), and in the i-PVR group versus the control group (P=0.02); there was no difference between the ni-PVR and control groups (P=0.29). CMR data confirmed the echocardiography results, with a significant difference in RV-PA coupling between the i-PVR and ni-PVR groups (RVSV/RVESV 0.9±0.2 vs 1.2±0.3mL/min/mL; P=0.01). CONCLUSIONS: This study demonstrates worse RV-PA coupling, despite normal RV systolic function, in patients with rToF with an indication for PVR. RV-PA coupling could be a sensitive marker of a progressive maladaptive RV response to long-standing volume overload in rToF before the onset of clinical symptoms and RV systolic dysfunction.

Coronary microvascular dysfunction and findings of heart failure with preserved ejection fraction in patients with microvascular angina.

BACKGROUND: Coronary microvascular dysfunction (CMD) may cause symptoms of myocardial ischemia (microvascular angina [MVA]), but recent studies suggested that it might also contribute to the syndrome of heart failure with preserved ejection fraction (HFpEF). In this study we assessed the relation of CMD with findings of HFpEF in MVA patients. METHODS: We enrolled 36 consecutive patients with MVA, in whom we assessed: 1) coronary blood flow (CBF) response to adenosine and cold pressor test (CPT) by color-Doppler echocardiography of the left anterior descending coronary artery; 2) complete echocardiographic examination; 3) N-terminal-pro-B-natriuretic peptide (NT-proBNP); 4) grade of dyspnea by the modified Medical Research Scale. RESULTS: Among patients, 15 had definite HFpEF findings (group 1), 12 had equivocal HFpEF findings (group 2) and 9 had no evidence of HFpEF findings (group 3). Group 1 patients were older, had more cardiovascular risk factors and higher NT-proBNP levels (P=0.018), and showed a higher prevalence of diastolic dysfunction. Left ventricle dimensions and systolic function, however, did not differ among groups. Dyspnea was also not significantly different among groups (P=0.19). CBF to adenosine was 1.85±0.47, 1.78±0.40 1.49±0.32 in group 1, 2 and 3, respectively (P=0.13). Similarly, CBF response to CPT was 1.57±0.4, 1.49±0.2 and 1.45±0.3 in the 3 groups, respectively (P=0.74). Both CBF response to adenosine and CPT showed no relation with the severity of dyspnea symptoms. CONCLUSIONS: Our data suggest that in patients with MVA there is no relation between the grade of impairment of coronary microvascular dilatation and findings of HFpEF.

Rapid Exclusion of COVID Infection With the Artificial Intelligence Electrocardiogram.

OBJECTIVE: To rapidly exclude severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using artificial intelligence applied to the electrocardiogram (ECG). METHODS: A global, volunteer consortium from 4 continents identified patients with ECGs obtained around the time of polymerase chain reaction-confirmed COVID-19 diagnosis and age- and sex-matched controls from the same sites. Clinical characteristics, polymerase chain reaction results, and raw electrocardiographic data were collected. A convolutional neural network was trained using 26,153 ECGs (33.2% COVID positive), validated with 3826 ECGs (33.3% positive), and tested on 7870 ECGs not included in other sets (32.7% positive). Performance under different prevalence values was tested by adding control ECGs from a single high-volume site. RESULTS: The area under the curve for detection of acute COVID-19 infection in the test group was 0.767 (95% CI, 0.756 to 0.778; sensitivity, 98%; specificity, 10%; positive predictive value, 37%; negative predictive value, 91%). To more accurately reflect a real-world population, 50,905 normal controls were added to adjust the COVID prevalence to approximately 5% (2657/58,555), resulting in an area under the curve of 0.780 (95% CI, 0.771 to 0.790) with a specificity of 12.1% and a negative predictive value of 99.2%. CONCLUSION: Infection with SARS-CoV-2 results in electrocardiographic changes that permit the artificial intelligence-enhanced ECG to be used as a rapid screening test with a high negative predictive value (99.2%). This may permit the development of electrocardiography-based tools to rapidly screen individuals for pandemic control.

Coronary provocative tests in the catheterization laboratory: Pathophysiological bases, methodological considerations and clinical implications.

The paradigm for the management of patients presenting with angina and/or myocardial ischemia has been historically centered on the detection and treatment of obstructive coronary artery disease (CAD). However, in a considerable proportion (30-50%) of patients undergoing coronary angiography, obstructive CAD is excluded. Thus, functional mechanisms may be involved in determining myocardial ischemia and should be investigated. In particular, coronary vasomotor disorders both at epicardial and at microvascular level may play a crucial role, but a definitive diagnosis of these disorders can at times be difficult, given the transience of symptoms, and often requires the use of coronary provocative tests. Of importance, these tests may provide relevant information on the pathogenic mechanism of myocardial ischemia, allowing physicians to tailor the therapies of their patients. Furthermore, several studies underscored the important prognostic information deriving from the use of coronary provocative tests. Nevertheless, their use in clinical practice is currently limited and mainly restricted to specialized centers, with only a minority of patients receiving a benefit from this diagnostic approach. In this review, we explain the pathophysiological bases for the use of provocative tests, along with their clinical, prognostic and therapeutic implications.

Assessment and pathophysiology of microvascular disease: recent progress and clinical implications.

The development of novel, non-invasive techniques and standardization of protocols to assess microvascular dysfunction have elucidated the key role of microvascular changes in the evolution of cardiovascular (CV) damage, and their capacity to predict an increased risk of adverse events. These technical advances parallel with the development of novel biological assays that enabled the ex vivo identification of pathways promoting microvascular dysfunction, providing novel potential treatment targets for preventing cerebral-CV disease. In this article, we provide an update of diagnostic testing strategies to detect and characterize microvascular dysfunction and suggestions on how to standardize and maximize the information obtained from each microvascular assay. We examine emerging data highlighting the significance of microvascular dysfunction in the development CV disease manifestations. Finally, we summarize the pathophysiology of microvascular dysfunction emphasizing the role of oxidative stress and its regulation by epigenetic mechanisms, which might represent potential targets for novel interventions beyond conventional approaches, representing a new frontier in CV disease reduction.

Clinical, angiographic and echocardiographic correlates of epicardial and microvascular spasm in patients with myocardial ischaemia and non-obstructive coronary arteries.

BACKGROUND: Coronary vasomotor dysfunction represents an important mechanism responsible for myocardial ischaemia in patients with non-obstructive coronary artery disease (CAD). The use of invasive provocative tests allows identifying patients with epicardial or microvascular spasm. Of note, clinical characteristics associated with the occurrence of epicardial or microvascular spasm have still not completely clarified. METHODS AND RESULTS: We prospectively enrolled consecutive patients undergoing coronary angiography for suspected myocardial ischaemia/necrosis with evidence of non-obstructive CAD and undergoing intracoronary provocative test for suspected vasomotor dysfunction. Patients with a positive provocative test were enrolled. Clinical, echocardiographic and angiographic characteristics of patients were evaluated according to the pattern of vasomotor dysfunction (epicardial vs. microvascular spasm). We included 120 patients [68 patients with stable angina and 52 patients with myocardial infarction and non-obstructive coronary arteries (MINOCA)]. In particular, 77 (64.2%) patients had a provocative test positive for epicardial spasm and 43 (35.8%) patients for microvascular spasm. Patients with epicardial spasm were more frequently males, smokers, had higher rates of diffuse coronary atherosclerosis at angiography and more frequently presented with MINOCA. On the other hand, patients with microvascular spasm presented more frequently diastolic dysfunction. At multivariate logistic regression analysis male sex, smoking, and diffuse coronary atherosclerosis were independent predictors for the occurrence of epicardial spasm. CONCLUSIONS: Our study showed that specific clinical features are associated with different responses to intracoronary provocative test. Epicardial spasm is more frequent in males and in MINOCA patients, whereas microvascular spasm is more frequent in patients with stable angina and is associated with diastolic dysfunction.

Characteristics and in-hospital outcome of patients with no ST-segment elevation acute coronary syndrome and no obstructive coronary artery disease in the era of high-sensitivity troponins.

BACKGROUND: Although some previous studies assessed characteristics and outcome of patients with suspected no-ST-segment elevation acute myocardial infarction (NSTEMI), but no obstructive coronary artery disease (NOCAD) at angiography, most were performed before high-sensitivity troponin assays were available. METHODS AND RESULTS: We reviewed data of patients admitted to our hospital with a suspicion of NSTEMI between 2013 and 2016. Patients with previous evidence of CAD (except those with fully percutaneous coronary revascularization) were excluded. Patients were divided into those with obstructive CAD and those with NOCAD (no coronary stenosis ≥50% in any vessel). The final population included 430 patients - 317 (73.7%) with CAD and 113 (26.3%) with NOCAD. Compared with CAD, NOCAD patients were younger, more frequently women, and had a lower prevalence of cardiovascular risk factors and peak troponin level. In-hospital death or myocardial infarction occurred in eight (2.5%) and two (1.8%) patients in CAD and NOCAD patients, respectively (P = 1.00). A lower left ventricular ejection fraction (LVEF) and left main CAD were the only independent predictors of in-hospital death and death or myocardial infarction. CONCLUSIONS: Among patients with suspect NSTEMI, about one-fourth showed NOCAD at angiography in the era of elevated sensitivity troponin assays and when excluding patients with largely predictable obstructive CAD. Higher troponin levels were associated with obstructive CAD, but a lower LVEF and left main disease only predicted in-hospital outcome in this population.