Absence Of Obstructive Coronary Disease Research Articles

Hypertensive Disorders of Pregnancy Increase the Risk for Myocardial Infarction: APopulation-Based Study.

Angiographic evidence of the anatomy of coronary arteries and the type of coronary artery lesions in women with a history of hypertensive disorders of pregnancy (HDP) are poorly documented. This study sought to determine the role of a history of HDP as a unique risk factor for early coronary artery disease (CAD) and type of acute coronary syndrome (ACS) (ie, atherosclerotic vs myocardial infarction with nonobstructive coronary arteries [MINOCA]) in women who underwent coronary angiography. This study used a population-based cohort of parous female patients with incident CAD who underwent coronary angiography and age-matched control subjects. The SYNTAX (Synergy between PCI [percutaneous coronary intervention] with TAXUS [Boston Scientific] and Cardiac Surgery) score was assessed to determine the complexity and degree of CAD; MINOCA was diagnosed in the presence of clinical acute myocardial infarction in the absence of obstructive coronary disease. A total of 506 parous female Olmsted County, Minnesota (USA) residents had incident CAD and angiographic data from November 7, 2002 to December 31, 2016. Women with HDP were younger than normotensive women at the time of the event (median: 64.8 years vs 71.8 years; P=0.030). There was a strong association between HDP and ACS (unadjusted P=0.018). Women with HDP compared with women with normotensive pregnancies were more likely to have a higher SYNTAX score (OR: 2.28; 95%CI: 1.02-5.12; P=0.046), and MINOCA (OR: 2.08; 95%CI: 1.02-4.25; P=0.044). A history of HDP is associated with CAD earlier in life and with a future risk for myocardial infarction with both obstructive and nonobstructive coronary arteries. This study underscores the need for timely detection and treatment of nonobstructive disease, in addition to traditional risk factors.

The Utility of Artificial Intelligence and Machine Learning in the Diagnosis of Takotsubo Cardiomyopathy: A Systematic Review

Abstract Introduction: Takotsubo cardiomyopathy (TTC) is a cardiovascular disease caused by physical/psychological stressors with significant morbidity if left untreated. Because TTC often mimics acute myocardial infarction in the absence of obstructive coronary disease, the condition is often underdiagnosed in the population. Our aim was to discuss the role of artificial intelligence (AI) and machine learning (ML) in diagnosing TTC. Methods: We systematically searched electronic databases from inception until April 8, 2023, for studies on the utility of AI- or ML-based algorithms in diagnosing TTC compared with other cardiovascular diseases or healthy controls. We summarized major findings in a narrative fashion and tabulated relevant numerical parameters. Results: Five studies with a total of 920 patients were included. Four hundred and forty-seven were diagnosed with TTC via International Classification of Diseases codes or the Mayo Clinic diagnostic criteria, while there were 473 patients in the comparator group (29 of healthy controls, 429 of myocardial infarction, and 14 of acute myocarditis). Hypertension and smoking were the most common comorbidities in both cohorts, but there were no statistical differences between TTC and comparators. Two studies utilized deep-learning algorithms on transthoracic echocardiographic images, while the rest incorporated supervised ML on cardiac magnetic resonance imaging, 12-lead electrocardiographs, and brain magnetic resonance imaging. All studies found that AI-based algorithms can increase the diagnostic rate of TTC when compared to healthy controls or myocardial infarction patients. In three of these studies, AI-based algorithms had higher sensitivity and specificity compared to human readers. Conclusion: AI and ML algorithms can improve the diagnostic capacity of TTC and additionally reduce erroneous human error in differentiating from MI and healthy individuals.

Quantification of myocardial blood flow using stress cardiac magnetic resonance for the detection of coronary artery disease

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): GE Healthcare. Background Myocardial blood flow (MBF) analysis using stress cardiac magnetic resonance (CMR) has been shown to detect obstructive coronary artery disease (CAD); however, evaluation of its diagnostic performance has primarily been limited to single-center studies. AQUA-MBF (Assessment of QUAntitative MBF using stress CMR) is an international study with the goal of assessing the diagnostic performance of stress MBF for the detection of CAD. In this study, we aim to determine how stress MBF assessment compared against visual analysis (VA) of stress CMR images for the detection of CAD. Methods. 144 individuals (89 (62%) men, age 62±16 years, 97 (68%) hypertension, 54 (38%) diabetes, 92 (64%) hyperlipidemia) from 9 centers who underwent dual sequence stress CMR (1.5T or 3.0T GE Healthcare) and also had either a coronary computed tomography angiography (CTA, n=31), invasive coronary angiogram (ICA, n=95), or low pre-test probability for CAD (n=18) were included. CAD was defined as the presence of: (1) a stenosis ≥50% in the left main coronary artery or ≥70% in the 1 major vessel based on ICA or CTA or (2) an invasive fractional flow reserve (FFR) ≤ 0.8. Absence of obstructive coronary disease (NOCAD) was defined as a no history of myocardial infarction and stenosis <50% by ICA or CTA, 50–70% stenosis with FFR>0.8, or a young individual with no cardiac risk factors. Myocardial perfusion imaging was performed during first pass perfusion of a gadolinium-based contrast agent following the administration of adenosine or regadenoson with a low-resolution image acquired to assess the arterial input function and 2–3 short axis slices acquired to assess myocardial perfusion. VA was performed by 2 experienced cardiologists who assigned a grade of 1–5 based on the probability a study was abnormal. Stress MBF values were determined for each of the 16 myocardial segments using Fermi deconvolution (CircleCVI). The global stress MBF was calculated as the average value of two segments with the lowest values from each of the three coronary artery territories. Unpaired t-test was used to compare stress MBF values between CAD vs NOCAD. Receiver-operating characteristics curves were used to determine diagnostic performance. Results. 60 patients had CAD (20: 1-vessel, 26: 2-vessel, and 14: 3-vessel) (Figure 1A) while 84 had NOCAD (Figure 1B). The global stress MBF in CAD was lower than in NOCAD (1.63±0.52ml/g/min vs 2.41±0.68ml/g/min, p<0.0001) (Figure 2A). Stress MBF had a higher AUC than VA (reader 1 – 0.83 vs 0.73, p = 0.07: reader 2–0.83 vs 0.71, p = 0.02). The optimal stress MBF cut-off value for detecting CAD was 2.05ml/g/min (Figure 2B). Conclusions. In this multicenter study, we show that global stress MBF reported as a single value can identify patients with CAD at least as accurately as VA performed by physicians experienced in the interpretation of stress CMR images.

P78 PSYCHIATRIC PATHOLOGIES PREVALENCE OF IN TAKOTSUBO SYNDROME

Abstract Background Tako Tsubo syndrome (TTS) is characterized by transient alterations of ventricular kinetics (ATC) in the absence of obstructive epicardial coronary artery disease. Materials 39 cases of TTS that came to our observation from 2005 to 2019 are described, the diagnosis was made on the basis of evidence of ATC, ECG alterations, increase necrosis markers in the absence of obstructive coronary disease, excluding myocarditis. Results 39 patients (PZ) (35 females and 4 males) diagnosed with TTS had an average age of 61 ± 13.21 years and symptoms at onset were mainly angina in 28 PZs (72%), dyspnea was present in 8 (20%) and syncope in 3 (8%). ECG changes were characterized by ST depression and/or negative T waves in 30 patients (77%), in 9 (23%) the ST segment was elevated. ATV involved apical segments (SAP) in 27 PZ (69%), 4 (10%) the basal segments (SBA), 2 (5%) the middle segments (SME) and 6 (15%) had focal points abnormalities (FOC). The average Ejection Fraction (FE) on admission was 36.85%, in PZ with ATV of SAP 33.96%, when involved SBA 41%, SME 43.5% and FOC 44.83%. Haemodynamic conditions were stable in 33 pts (84%), 3 pts (8%) presented cardiogenic shock, 3 (8%) pulmonary edema. Arrhythmias were present in 1/3 of the cases. Atrial fibrillation in 38%, extrasystolic arrhythmia in 30%, one patient with sustained ventricular tachycardia, and three patients with total BAV (23%) of which one in shock. In 10% of cases (4 PZ) there was a subvalvular aortic gradient at discharge disappeared. In 8% (3 PZ) was a recurrent TTS. 92% of the PZ reported a psychophysical stress in the 24 hours preceding the event, and a psychiatric pathology was present in 90%. However, only in 60% of cases the psychiatric diagnosis was known on admission, in the remaining 40% the diagnosis was made subsequently, and among the PZ being treated only in ¼ of the cases was it judged adequate. Conclusions In our series, SAP involvement was associated with lower EF values and greater hemodynamic compromise. Involvement of SME, SBA or FOC was associated with higher EF values and less hemodynamic compromise. A psychiatric pathology was present in over 90% of the PZ even if in 40% of the cases it was not ascertained at the time of admission, and in 75% of the PZ in which the diagnosis was known, the treatment was not adequate.

272 A SUDDENLY RIGHT-TO-LEFT SHUNT: THE IMPORTANCE OF EVALUATING PATENT FORAMEN OVALE DURING CARDIOPULMONARY EXERCISE TESTING

Abstract A 55-years-old male affected by heart failure with reduced ejection fraction (HFrEF) was accepted into the Cardiology Department for increasing dyspnea during the last few months. He previously underwent implantation of a biventricular implantable cardioverter defibrillator (ICD) in primary prevention. Medical history included healthy coronary vessels at invasive coronary angiography and an episode of transient ischemic attack (TIA). The patient was referred to our center to evaluate the dyspnea components and to establish an etiology for the novel onset of left ventricular impairment. He underwent a left-right catheterization that did confirm the absence of obstructive coronary disease and signs of pulmonary hypertension (PH) at rest. The transthoracic echocardiogram showed a dilated left ventricle and global hypokinesia (LVEF of 35%). During the stay, the therapy was further optimized according to the latest European guidelines. Before discharge, in order to better assess the dyspnea and the limited tolerance to exercise, a cardiopulmonary exercise testing (CPET) was performed. CPET showed that the VO2 peak was severely reduced compared to the predicted value (16.8 ml/kg/min, corresponding to 51% of the predicted). After 6 minutes of exercise, at around 60 WR, a considerable increase in PETO2 and RER with a concomitant decrease in PETCO2 and a slight oxygen desaturation were observed. Also, a deep increase in VE/VCO2 slope was seen, underlying an exercise-induced pulmonary hypertension. In the suspicion of an inter-atrial shunt, a subsequent rest transthoracic echocardiogram with a bubble test was performed, demonstrating the presence of a patent foramen ovale (PFO). Discussion The foramen ovale is a vestigial communication between the atria that works as a bypass of the pulmonary circulation during fetal life and then seals at birth after the start of breathing in most people. In around 25% of adults, patency of foramen ovale persists and, in some cases, can lead to a source of a right-to-left shunt, particularly in patients with heart failure that can experience PH at rest or during exercise. This may allow a mixture of oxygenated and non-oxygenated blood that affects pulmonary gas exchange efficiency and may allow blood clots formed in the right circulation to embolize into the left circulation. From a pathophysiological point of view, a right-to-left passage of deoxygenated blood induces the activation of chemoreceptors which induce hyperventilation to adequately compensate for the high amount of CO2 in blood from the right sections of the heart. In people not experiencing pulmonary pressure increase during exercise, right-to-left shunt via a PFO is very unlikely since left atrial pressure is higher than right atrial pressure. However, in the presence of PH, right atrial pressure can overcome left atrial pressure and force venous blood through the defect directly into the systemic circulation. The concomitant increase in VE/VCO2 slope underlines exercise-induced PH, which is frequently associated with heart failure and further contributes to exercise intolerance. Conclusions In the presented case, CPET helped diagnose a misunderstood PFO with a right-to-left shunt induced by effort in a patient with a previous TIA. This observation demonstrates that it could be helpful to identify this eventuality during exercise, to discern patients with higher risk of cardiovascular events who would benefit from a percutaneous closure.

Coronary artery disease in women.

Cardiovascular disease is the leading global cause of death in women but remains underdiagnosed and undertreated. Health professionals play an important role in improving the heart health of Australian women. Routine heart health checks should be offered to all women 45 years of age and older and to all Aboriginal and Torres Strait Islander women 30 years of age and older. Cardiovascular risk assessment in women must include traditional and sex-specific risk factors, including their pregnancy history and early-onset menopause. Women with pregnancy-related hypertensive and metabolic disorders have an increased long-term cardiovascular risk and require close monitoring. Women with acute coronary syndrome may not experience classical chest pain. More often, they experience cardiovascular events in the absence of obstructive coronary disease and have poorer cardiovascular outcomes. The recognition of sex-specific differences and more sex-specific trials are key to improving clinical outcomes.

Abstract 15675: Mid-Ventricular Hypertrophic Cardiomyopathy Presenting With Minoca

Background: Mid-ventricular hypertrophic obstructive cardiomyopathy (HOCM) is an uncommon form of cardiomyopathy that is linked to an apical aneurysm, increasing the risk of sudden death. Cases: We described four patients who presented with chest pain or SOB. Troponin elevation, acute myocardial infarction on cardiac MRI and absence of obstructive coronary disease confirmed the diagnosis of MINOCA. Echo revealed a pressure gradient between the apical and basal chambers of the left ventricle. Cardiac MRI showed mid-ventricular HOCM and mid-cavity obliteration with akinetic apical chamber LGE revealed areas of sub-endocardial or transmural myocardial infarction at the level of obstruction and at the apical segments distal to the obstruction. The presence of myocardial edema on tissue mapping in the same area suggested acute myocardial injury (Figure). Discussion: The pathogenesis of development of apical myocardial scarring and aneurysm formation in mid-ventricular HOCM remains unknown. Other variant of hypertrophic cardiomyopathy shows mid-myocardial foci of scar inside the hypertrophied segments, indicating fibrosis. Whereas in our patients, the LGE revealed a sub-endocardial or transmural infarct (myocardial infarction pattern) - an uncommon pattern in other hypertrophic cardiomyopathy variants. This pattern and elevation of troponin during the acute phase of illness supports the hypothesis that apical aneurysm is due to apical myocardial ischemia in mid-ventricular HOCM. Tissue characterization and pattern of scar by cardiac MRI in these patients could be useful in understanding the pathophysiology of this type of HOCM.

Lower stress perfusion in patients with myocardial infarction with non-obstructive coronary arteries compared to controls in long-term follow-up with quantitative perfusion mapping

Abstract Introduction Myocardial infarction with non-obstructive coronary arteries (MINOCA) constitutes a heterogenous condition with different coronary, cardiac and non-cardiac etiologies. Cardiovascular magnetic resonance imaging (CMR) has emerged as an important diagnostic tool in recent years and is now recommended in patients with MINOCA as a working diagnosis. However, despite early CMR following admission for MINOCA, no cause can be found in around 25% of all patients. A pathophysiological mechanism may be diffuse global coronary microvascular dysfunction (CMD) which has emerged as an important cause of myocardial ischemia. Quantitative adenosine stress CMR perfusion mapping allows for absolute quantification of myocardial perfusion, reflecting CMD in the absence of obstructive coronary disease in MINOCA patients. Purpose To study the presence of CMD in MINOCA patients with an initial normal CMR scan compared to healthy controls. Methods Patients from the multicenter myocardial infarction in our city with normal Coronaries 2 (SMINC-2) study, with a normal CMR scan 2–4 days after hospitalization, and healthy age- and sex-matched controls underwent stress perfusion at 1.5T (MAGNETOM Aera). Native rest T1 and T2 short-axis maps were acquired. Quantitative perfusion maps were acquired during adenosine stress (140 micrograms/kg/min) and at rest following an intravenous contrast bolus (0.05 mmol/kg of gadoteric acid, Gd-DOTA). Post contrast T1 maps were acquired after intravenous contrast (total dose 0.2 mmol/kg) rendering extracellular volume (ECV) maps. Global native T1, T2, ECV and rest and stress perfusion values were acquired by averaging segmental values per patient. Myocardial perfusion reserve (MPR) was calculated as perfusion in stress divided by rest. Values were presented as mean±standard deviation and compared with the independent t-test in normally distributed data, and with the Mann-Whitney U test in non-normally distributed data. Clinical data regarding cardiovascular risk factors, smoking and medications were presented as numbers (percentages) and compared with Fisher's exact test. Rate pressure product (RPP) was calculated as systolic blood pressure multiplied by heart rate in rest and stress. Results In total, 15 patients (59±16 years old, 60% female), and 15 healthy age- and sex-matched controls, were included. There was a trend towards higher incidence of hypertension in patients compared to controls, however no difference in other risk factors (Table 1). Compared to controls, MINOCA patients had lower perfusion in stress (Figure 1). There was no difference in global native T1, T2, ECV, rest perfusion, MPR or hemodynamic parameters between the MINOCA patients and the controls (p>0.05 for all, Table 1). Conclusions Myocardial stress perfusion is lower in MINOCA patients with a normal initial CMR scan compared to age- and sex-matched controls suggesting CMD as a possible pathophysiological mechanism in MINOCA. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Swedish Heart and Lung Foundation

Left Ventricular Diastolic Function: Comparison of Slow Coronary Flow Phenomenon and Left Ventricular Hypertrophy in the Absence of Obstructive Coronary Disease.

BackgroundAn interplay of myocardial structural abnormalities and coronary arterial dysfunction underlies the worsening left ventricular compliance. The conventionally used angina drugs have demonstrated a beneficial effect on both angina and coronary flow in cases with microvascular dysfunction and non-obstructive coronary disease. Despite that, vasoactive therapy only partially affects diastolic function in this patient population.PurposeThis retrospective study was planned to evaluate the association of myocardial mass, delayed epicardial coronary flow, and vasoactive drugs with parameters of diastolic function in two cohorts with preserved left ventricular function and non-obstructive coronary disease in patients with slow coronary flow phenomenon (SCFP) and patients with the hypertensive disease and left ventricular hypertrophy.Material and methodsThe epicardial coronary flow was evaluated in 48 patients with unstable angina in the absence of coronary stenosis >50%, by applying the methods of corrected thrombolysis in myocardial infraction frame count (cTFC). The abnormalities in the left ventricular function were assessed by echocardiography using PW-Doppler of the diastolic mitral inflow and tissue Doppler imaging. Twenty-one (43.8%) patients were diagnosed with SCFP, and twelve patients (25%) had slow epicardial coronary flow, hypertensive disease, and ventricular hypertrophy (SFLVH). The remaining 15 (31.3%) were patients with ventricular hypertrophy, hypertension, and non-delayed epicardial coronary flow (NFLVH).ResultsThe patients with SFLVH showed reduced peak early diastolic lateral mitral annular velocity (e’L) when compared to SCFP (7.1±1.9cm/s vs 8.6±2.1 cm/s, p=0.045) and NFLVH (7.1±1.9 cm/s vs 8.7±1.8 cm/s, p=0.018). A borderline significant difference was observed for the peak early diastolic septal mitral annular velocity (e’S) between the patients with SFLVH and SCFP ( 7.0±1.3 cm/s vs 8.3±2.1 cm/s, p=0.057). The ratio of mitral diastolic inflow velocity to early diastolic velocity of the mitral annulus (E/e’) in the SFLVH group was a tendency higher than E/e’ of the patients with SCFP (9.8±3.1 vs. 8.2±2.1, p=0.084) and NFLVH (9.8±3.1 vs. 7.8±1.5, p=0.051) .In the group with left ventricular hypertrophy, E/e’ >10 was more frequently observed in patients with a marked delay in the epicardial flow (33.1 ± 13.1 frames vs. 25.4 ± 11.8 frames, p=0.011) and higher left ventricular mass (146.9 ± 17.7 g/m2 vs. 126.1 ± 121.5 g/m2, p=0.027).ConclusionsPatients with microvascular angina represent a diverse population. The echocardiographic parameters of left ventricular relaxation (e') and end-diastolic pressure (E/e’) are abnormally altered in the population with left ventricular hypertrophy compared to SCFP. The delayed epicardial flow further impairs diastolic function in hypertensive patients with hypertrophy and non-obstructive coronary disease.

Five-year follow-up and outcomes of takotsubo/stress cardiomyopathy in a single centre- an irish perspective

Abstract Funding Acknowledgements Type of funding sources: None. Background Takotsubo Cardiomyopathy (TC) is an acute cardiac presentation characterised by acute myocardial injury and transient left ventricular systolic dysfunction, in the absence of obstructive coronary disease(1). Postulated causes include catecholamine excess, microvascular dysfunction, and multi-vessel coronary artery spasm. Predominantly seen in post-menopausal women, frequently triggered by emotional or physical stressor with in-hospital mortality rate reported at 2-5%(2). We present a single centre experience of TC with five-year follow-up. Methods We performed a retrospective descriptive study of patients with a diagnosis of TC coded by Hospital In-Patient Enquiry data from a tertiary level Irish hospital between 2010 and 2016. Data collection was electronic patient records/chart review. 21 cases were confirmed by modified Mayo Clinic criteria(3). Three patients were lost to follow up, two patients died during the follow-up period and one patient was excluded due to a focal area of transmural infarction on follow-up cardiac magnetic-resonance imaging (CMRI). Follow up data was obtained on sixteen patients up to 01/08/2021. Statistical analysis using SPSS v. 27, expressed as mean +- SD in %. Results Mean age at event was 64 +/- 12 years, 95% were female. Triggers identified in 55% of cases; emotional stressors in 35%, physical stressors in 25%. All had raised Troponin I (peak 3.13 ± 2.42ng/ml) and electrocardiograph (ECG) changes. Coronary angiography performed in all with no or mild CAD in seventeen and moderate CAD in two cases. CMRI was performed in 60% (n = 12) at on average 14.8 months post discharge. Average left ventricular ejection fraction (LVEF) was 31+/- 8% and 62+/-7% at diagnosis and follow up respectively, improving in all cases with mean improvement of 30.8 +/-11% (p < 0.001). Three patients had a further TC event. Two of the cases underwent angiography at the time of second presentation with normal coronary arteries and follow-up imaging showed full LVEF recovery in both cases. The third patient is awaiting follow-up CMRI. Of the recurrent cases two occurred despite best medical therapy. Two of the cases showed full recovery of LVEF between events and one showed minimal LVEF improvement prior to recurrence but full recovery after the second event. All patients who remained in Ireland had initial follow up (n = 15), 46% attend Cardiology outpatients in 2021. Conclusions Our demographic data is similar to previous studies with the majority of cases occurring in postmenopausal women(4). Our mortality rate was 9.5%, current published prognostic data in TC are limited and conflicting(2). The recurrence rate among our small cohort was 16.6% (n = 3) despite cardio-protective medications in two of the three cases, higher than previous reviews(5). The time to clinical and imaging follow up was discordant but all patients in our follow up group regained a normal LVEF which is very reassuring and in-keeping with prior studies. Abstract Figure. TTE apical 4-chamber view Abstract Figure. CMRI 4-chamber view end systole

The Role of Cardiac Magnetic Resonance in Myocardial Infarction and Non-obstructive Coronary Arteries.

Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) accounts for 5–15% of all presentations of acute myocardial infarction. The absence of obstructive coronary disease may present a diagnostic dilemma and identifying the underlying etiology ensures appropriate management improving clinical outcomes. Cardiac magnetic resonance (CMR) imaging is a valuable, non-invasive diagnostic tool that can aide clinicians to build a differential diagnosis in patients with MINOCA, as well as identifying non-ischemic etiologies of myocardial injury (acute myocarditis, Takotsubo Syndrome, and other conditions). The role of CMR in suspected MINOCA is increasingly recognized as emphasized in both European and American clinical guidelines. In this paper we review the indications for CMR, the clinical value in the differential diagnosis of patients with suspected MINOCA, as well as its current limitations and future perspectives.

Assessing the Appropriateness and Effectiveness of Coronary CT Angiography in COVID-19 Patients with Chest Pain

Coronary CT Angiography (CCTA) is well established for Chest Pain (CP) evaluation to assess coronary artery stenosis. However, the appropriateness of CCTA for COVID-19 patients with CP is unclear because a cardiac cause of CP in COVID-19 patients can be multifactorial, from direct viral myocardial injury to secondary hypercoagulability and to coronary stenosis [1]. The purpose of this report is to examine the appropriateness of CCTA for CP evaluation in laboratory confirmed COVID-19 patients. We retrospectively reviewed consecutive COVID-19 patients with CP between March 7, 2020 and January 2021. COVID-19 diagnosis was confirmed using the Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) test (Cobas SARS-CoV-2, Roche, Indiana, USA and the Xpert Xpress SARS-CoV-2, Cepheid, California, USA). A waiver for individual consent was approved by the Institutional Review Board. Patient’s demographic data, vital signs and ECG were charted prospectively in the CT reporting database. The laboratory results were retrospectively collected from the electronic medical records. The European Consortium clinical pre-test probability score for coronary artery disease was calculated based from the clinical criteria including age, sex, CP type, diabetes mellitus, smoking status, hypertension, and dyslipidemia [2] where the low pretest probability was defined as <5%, intermediate probability 5-70 % and high probability >70%. Patients less than 40 years old (N=3) were treated as if they were 40 years of age in order to calculate their score. The score was calculated to predict coronary stenosis >50% by CCTA, which was performed using a 320-detector CT (Acquilion One, Vision, Canon, USA) with prospective ECG gating. Among 40 patients studied, 21 were female and the mean age was 53 years. Of those, 34 were hospitalized and 6 were outpatients. The patients’ demographics are shown in the table. No patient was known to have pre-existing coronary artery disease. Based on the clinical criteria there were 11 patients having low pretest probability <5% and the remaining 29 having intermediate probability ranging from 5% to 47%. None had high pretest probability. All patient had 12-lead ECG prior to CCTA. ST/T wave abnormalities were found in 14 (35%) and Q wave abnormality in 5 (13%) patients. Of the 32 patients who had Troponin tested, only 1 patient had Troponin I elevation. Out of the 38 patients with calcium score imaging performed, 23 (61%) had zero calcium score. To minimize radiation exposure 2 patients did not receive calcium score imaging due to young age (<30 years). The subsequent CCTA was normal in one and severely abnormal with 3-vessel disease in the other. Among the patients with low pretest probability (N=11) none had significant coronary stenosis of >50%. Of the remaining 29 patients with intermediate probability, 8 (28%) had significant stenosis. One female patient having an intermediate pre-test probability of 11% presented with an acute coronary syndrome with ST segment depression and peak cardiac Troponin-I elevation of 11.3 ng/dL. Her coronary calcium score was zero and CCTA was normal. The subsequent cardiac MRI showed acute myocardial infarction with evidence of microvascular obstruction. Another patient having intermediate probability of 47% had a coronary calcium score of 5717 who was imputed to have significant coronary stenosis without undergoing CCTA. The ECG findings of ST/T or Q wave abnormalities did not differentiate those with or without significant coronary stenosis by CCTA. Table 1: Demographics (N=40). In this case series we found that clinical risk stratification using The European Consortium pre-test probability score was effective in COVID-19 patients with CP. No patients with low pretest probability were found to have significant coronary stenosis. In contrast, 28% of patients with intermediate pretest probability had significant coronary stenosis. While fever and respiratory distress are often the most prominent clinical presentations for hospitalized COVID-19 patients, CP can also present as a major complaint or in combination with other symptoms, making the clinical assessment difficult based on symptoms alone. There are many possible cardiac causes for CP, including but not limited to acute coronary syndrome, myocarditis and pericarditis in COVID-19 patients. Even in the setting of STelevation acute myocardial infarction the absence of obstructive coronary disease is common by invasive angiography in COVID-19 patients [3]. Therefore, it is challenging to choose the appropriate diagnostic test for CP evaluation in COVID-19 patients. Nevertheless, our findings suggest that the clinical risk stratification combined with CCTA remains to be appropriate and effective for coronary artery disease evaluation in COVID-19 patients with CP.

A sneak peek on Takotsubo Syndrome

Abstract Funding Acknowledgements Type of funding sources: None. INTRODUCTION Takotsubo syndrome (TS) is characterized by transient wall motion abnormality of the left ventricle, which may happen in response to different triggers. AIM To characterize the population with confirmed diagnosis of TS. METHODS We analysed retrospectively 129 patients (pts) admitted in our center from 2010 to 2018 with this presumptive diagnosis. 29pts were excluded because TS wasn´t confirmed. For each pt we evaluate clinical characteristics, exams results, inhospital complications and long-term outcomes (minimum FUP of 1 year). RESULTS The average age was 66 years and 89% were females. Regarding the cardiovascular (Cv) risk factors, 78% had hypertension, 53% dyslipidemia and 19% Diabetes mellitus. In relation to noncardiovascular comorbidities it’s important to point out that 32% had psychiatric disorders. The trigger was emotional in 37%, physical in 18%, and unidentifiable in 45%. Concerning the clinical presentation 72% had Killip(K) 1 and 13% K≥3 at admission. The initial electrocardiogram had ST-elevation in 37%, T wave inversion in 64% and a mean QTc interval of 470ms. The mean ejection fraction (EF) by echocardiogram was 37%, with apical ballooning in 83% and at least moderate mitral regurgitation (MR) in 11%. Only 16% had intraventricular pressure gradient. Coronarography revealed absence of obstructive coronary disease in 71% of pts. In addition, 51% of pts underwent cardiac magnetic resonance (CMR), which had an increase usage since 2013. The mean time until the CMR was 14 days, which may explain why only 14% had segmental kinetic changes. It’s noteworthy that the mean peak NTproBNP/troponin I ratio was 1,4 ± 2,9. We compared the ratio in TS with EF < 40% with the one obtained in a cohort of ST-elevation myocardial infarction (MI) with EF < 40% and found statistically difference (1,7 ± 3,8vs0,01 ± 0,03; p < 0,001). Considering inhospital complications, 6% had intracardiac thrombus, 2% acute severe MR, 2% ventricular dysrhythmia and 2% died. During the FUP, 2% had recurrence, 4% had acute heart failure hospitalizations an 17% died. CONCLUSION Despite increased awareness TS is still poorly recognized. Lack of non-invasive tools for reliable diagnosis obliged the use of coronarography. It’s noteworthy that the peak NTproBNP/troponin I ratio may help to differentiate TS from MI and the use of CMR should be encouraged to exclude other causes. Although considered a benign condition, significant in-hospital mobility and 2% mortality was observed.

Patients with aortic stenosis exhibit early improved endothelial function following transcatheter aortic valve replacement: The eFAST study

BackgroundPatients with severe aortic stenosis (AS) exhibit systemic endothelial dysfunction, which can be associated with myocardial ischaemia in absence of obstructive coronary disease. Transcatheter aortic valve replacement (TAVR) is used to treat severe AS in patients with high or prohibitive surgical risk. However, it remains unknown whether endothelial function recovers post-TAVR. We therefore sought to assess the early and late changes in flow-mediated dilation (FMD), a measure of endothelial function, following TAVR. MethodsPatients undergoing TAVR for severe AS had ultrasound assessment of brachial endothelial-independent and -dependent FMD. Measurements were performed pre-TAVR, at early follow-up (<48 h post-TAVR) and late follow-up (4–6 weeks post-TAVR). Results27 patients (mean age 82.0 ± 7.0; 33.3% female) were recruited; 37.0% had diabetes mellitus and 59.3% had hypertension. Brachial artery FMD increased from 4.2 ± 1.6% (pre-TAVR) to 9.7 ± 3.5% at early follow-up (p < 0.0001). At late follow-up, improvement compared with early follow-up was sustained (8.7 ± 1.9%, p = 0.27). Resting brachial arterial flow velocities decreased significantly at late follow-up (11.24 ± 5.16 vs. 7.73 ± 2.79 cm/s, p = 0.003). Concordantly, at late follow-up, there was decrease in resting wall shear stress (WSS; 14.8 ± 7.8 vs. 10.6 ± 4.8dyne/cm2, p = 0.01), peak WSS (73.1 ± 34.1 vs. 58.8 ± 27.8dyne/cm2, p = 0.03) and cumulative WSS (3543 ± 1852 vs. 2504 ± 1089dyne·s/cm2, p = 0.002). Additionally, a favourable inverse correlation between cumulative WSS and FMD was restored at late follow-up (r = −0.21 vs. r = 0.49). ConclusionEndothelial function in patients with AS improves early post-TAVR and this improvement is sustained. This likely occurs as a result of improved arterial haemodynamics, leading to lower localised WSS and release of vasoactive mediators that may also alleviate myocardial ischaemia.

Stress cardiomyopathy: Medical studies and extensive review.

Stress cardiomyopathy (SC) was first reported in the year 1983. It is narrated as critical but quite commutative left ventricular (LV) malfunction mostly caused by poignant or psychological disorder. Numerous variations of SC have been described as well as reverse stress cardiomyopathy (rSC) which is an adaptation identified by the decreased muscle movement related with hyperkinesis that reconciles impetuously. The signature of rSC is a medical demonstration alike to syndrome by an acute coronary, with no obvious difficult coronary artery disease. The occurrence of SC is approximated to be 4% of all victims conferring with gleaned syndrome by acute coronary. The portion of victims conferring with the rSC transfiguration out of all SC patients has been inconstant, varying from 1 to 24%. Reverse stress cardiomyopathy cases are found to be common with young people, less decrease in left ventricular ejection fraction (LVEF) and more neurological disease compared to the SC. While the correct phenomenon of rSC is undetermined, postulated methods comprises of coronary microvasculature impairment, coronary artery spasm, and estrogen deficiency. Patients with rSC typically suffer with chest pain after an emotional or Psychological stressful event. The rSC can also be happened by general anesthesia, or neurological conditions. The diagnosis of rSC demands the presence of new electrocardiogram (EKG) abnormalities or elevated cardiac troponin, and absence of obstructive coronary disease, pheochromocytoma, or myocarditis. The consideration of rSC is quite analogous to that of SC, which is predominantly supportive with the treatment of complications. The recrudescence rate of rSC is around 12%. The most frequent complications of rSC include pericardial effusions, and development of LV thrombi.

Searching for the final diagnosis using cardiac magnetic resonance in MINOCA patients

Abstract Introduction In patients with clinical evidence of acute myocardial infarction (AMI), absence of obstructive coronary disease does not imply absence of acute thrombotic process. Thereafter, it can be designated as Myocardial Infarction with Non-obstructive Coronary Arteries (MINOCA). In these cases, performing Cardiac Magnetic Resonance (CMR) can be essential for establishing a final diagnosis, due to evaluation of the presence and pattern of late enhancement. Purpose The aim of this study is to evaluate the diagnostic and prognostic impact of cardiac magnetic resonance in patients with a possible diagnosis of MINOCA. Methods A 7-years prospective study in our centre, which included all patients proposed to CMR with a presumptive diagnosis of MINOCA due to acute chest pain, troponin raise and absence of angiographically significant coronary disease (luminal stenosis of &amp;lt;50%). All patients performed functional, anatomical evaluation, as so late gadolinium enhancement search. We analysed clinical characteristics, electrocardiographic presentation, echocardiographic and coronariography results. A presumptive diagnosis was elaborated after coronariography and comparison was made with the definitive one after CMR. Results A total of 85 patients were included, 53% were male, with a mean age of 49±20 years old. Clinical history of hypertension was observed in 52% patients, 34% had dyslipidaemia, 8% with diabetes, obesity was present in 21% of patients and smoking habits in 33%. At admission, 47% had ST segment elevation, so emergent coronariography was performed. The mean highest troponin I was 7,54±9,39ng/mL. Late gadolinium enhancement was observed in 50 (59%) of patients. After CMR realization a final diagnosis of MINOCA was made in only 13 patients (15%) and in 51 patients (60%) CMR evaluation allowed a diagnosis modification, with impact on patients' management and prognosis. Of these 51 patients, a definitive diagnosis of myocarditis was seen in 65% of cases, of Takotsubo's myocardiopathy in 27%, and hypertrophic cardiomyopathy in 8%. In 21 (25%) of patients, late gadolinium enhancement was not found. However its absence could exclude type 1 AMI as definitive diagnosis. Conclusion CMR is a fundamental technique on MINOCA patients' management. In our population, performing CMR allowed initial diagnosis modification in about two thirds of the cases, with important therapeutic and prognostic implications. Funding Acknowledgement Type of funding source: None

833 Haemodynamic Changes Post Aortic Valve Replacement Lead to Early Improvement in Endothelial Function: Results From the eFAST Study

Severe aortic stenosis (AS) patients exhibit impaired coronary flow reserve (CFR), resulting in myocardial ischaemia in absence of obstructive coronary disease. Although endothelial dysfunction is known to contribute towards impaired CFR, it remains unknown whether endothelial function recovers following relief of AS. We therefore sought to assess the early and late changes in endothelial function following aortic valve replacement (AVR). Patients undergoing transcatheter or surgical AVR for severe AS had ultrasound assessment of endothelial-independent and -dependent flow mediated dilation (FMD). Measurements were performed prior to, 24hrs after and 28 days after intervention. Intraobserver FMD reproducibility was excellent (intraclass correlation coefficient 0.96, p<0.001). 30 patients were recruited (33% female), with twenty-seven (90%) undergoing transcatheter AVR. FMD significantly increased from 4.6±2.2% (pre-AVR) to 9.9±3.3% 24hrs post-procedure (p<0.0001). Repeat FMD at 28 days demonstrated that this improvement was sustained (8.7±1.9%, p<0.0001 compared with pre-AVR). Cumulative brachial WSS (represented as AUC) decreased progressively (3665±1810 vs 3228±1414 vs 2558±1101(dynxs)/cm2, p=0.001). In addition, the positive correlation between brachial WSS AUC and FMD was restored following AVR (r=0.05 pre-AVR vs r=0.52 at 28days). Our data shows that endothelial function in patients with AS improves within 24h after AVR and that this improvement is sustained. We hypothesise that this likely occurs as a result of improved arterial haemodynamics, leading to lower localised WSS and release of vasoactive mediators that may also alleviate myocardial ischaemia.

P812Takotsubo cardiomyopathy: phenotypic diversity and contemporary management

Abstract Background Takotsubo Cardiomyopathy represents an acute transient decline in left ventricular (LV) function occurring in the absence of obstructive coronary artery disease or acute plaque rupture. Therapeutic strategies vary due to a paucity of evidence-based guidelines. Purpose To evaluate clinical and biochemical characteristics, management approach and outcomes in a contemporary cohort of patients with Takotsubo Cardiomyopathy across two tertiary centres in Victoria, Australia. Neurohormonal associations were explored by characterising the prevalence of pre-existing endocrinopathies and malignancy. Methods We conducted a retrospective study of 240 patients with Takotsubo Cardiomyopathy diagnosed between 2008–2018, utilising data from electronic medical records. Results Patients were predominantly female (91.3%, mean age 66±12 years), smokers (48.3%), and hypertensive (55.0%). A small proportion (16.7%) had pre-existing malignancy (breast 30%, gastrointestinal 23%, genitourinary 19%, lung 9%, other 19%) or endocrine disease (12.5%), largely driven by thyroid disease (94%). Troponin rise was common (94.6%; peak troponin 6.4±13μg/L), though few presented with ST-elevation (21.7%). Psychosocial stress was prevalent (44.6%) compared with physical illness (39.2%) or an unidentified precipitant (16.7%). Management was heterogeneous. Many were discharged on aspirin (37.7%), dual antiplatelet therapy (34%) or statins (35.9%) in the absence of obstructive coronary disease or other clinical indication and were frequently continued beyond 1 year. ACE inhibitors or angiotensin receptor blockers were prescribed in 83.7%, beta blockers in 84.9% or both in 74.9% (continuing beyond 1 year in 60.4%). LV dysfunction occurred in 81.7% at diagnosis (mean LV ejection fraction (LVEF) 45±11%), recovering in 91.3% (mean LVEF 62±8%; 17.2% increase, p&lt;0.001) on repeat echocardiography (mean 107±154 days). Follow up occurred in 81.4%, though most patients with normalised LV function continued heart failure therapy (83.6%). 12-month mortality was rare (7%) as was recurrence (5.1%). Conclusions Management of Takotsubo Cardiomyopathy remains challenging due to phenotypic diversity, variable therapeutic approach and unclear treatment duration. Pre-existing illness, including malignancy and endocrinopathy, may provide a substrate for the development of Takotsubo Cardiomyopathy or amplify cardiac adrenoreceptor sensitivity. Enhanced understanding of possible neurohormonal and cellular mechanisms may facilitate targeted management and preventive strategies. The role of antiplatelets or lipid lowering therapy is not supported in existing literature, however, as this study highlights, they continue to feature heavily in the Takotsubo treatment armamentarium. Further studies are needed to enhance understanding of underlying mechanisms and establish a standardised treatment approach with targeted therapy to promote LV recovery and prevent recurrence. Acknowledgement/Funding None

How to Diagnose and Manage Angina Without Obstructive Coronary Artery Disease: Lessons from the British Heart Foundation CorMicA Trial.

Patients with symptoms and/or signs of ischaemia but no obstructive coronary artery disease (INOCA) present a diagnostic and therapeutic challenge. Microvascular and/or vasospastic angina are the two most common causes of INOCA; however, invasive coronary angiography lacks the sensitivity to diagnose these functional coronary disorders. In this article, the authors summarise the rationale for invasive testing in the absence of obstructive coronary disease, namely that correct treatment for angina patients starts with the correct diagnosis. They provide insights from the CORonary MICrovascular Angina (CorMicA) study, where an interventional diagnostic procedure was performed with linked medical therapy to improve patient health. Identification of these distinct disorders (microvascular angina, vasospastic angina or non-cardiac chest pain) is key for stratifying INOCA patients, allowing prognostic insights and better patient care with linked therapy based on contemporary guidelines. Finally, they propose a framework to diagnose and manage patients in this common clinical scenario.

Evaluation of plasma catestatin levels in patient with coronary slow flow

Objectives: Coronary slow flow (CSF) is characterized by delayed opasification of the coronary arteries in the absence of obstructive coronary disease. Catestatin has several cardiovasculer actions, in addition to diminihed sympato-adrenal flow. The study was to investigated associations between CSF and plasma catestatin levels. Method:. This study included 45 CSF patients (37 male, mean age 48 ± 9.5 years) and 30 control individuals (24 male, mean age 48.4 ± 9 years). Coronary flow was quantified according to the TIMI (Thrombolysis in Myocardial Infarction) frame count method for coronary arteries. Serum catestatin levels taken from blood samples were measured by ELISA method. These parameters were compared between the groups. Results: When compared with to the control group the serum catestatin levels was found higher in the CSF group. In addition to this, mean platelet volume was also significantly higher in patients with coronary slow flow. Conclusions: Our study revealed that catestatin levels are increased in patients with CSF. Coronary slow flow that increased catecholaminergic sympathetic system activities seem to be among the reasons of endothelial dysfunction.