2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

Discrepancy between plaque vulnerability and functional severity of angiographically intermediate coronary artery lesions

This study sought to investigate the relationship between physiological severity and plaque vulnerability of intermediate coronary artery stenoses as assessed by fractional flow reserve (FFR) and near-infrared spectroscopy-intravascular ultrasound (NIRS-IVUS). We included vessels where both FFR and NIRS-IVUS were performed. A positive FFR was defined as FFR ≤ 0.80. Lipid core burden index of the entire target vessel (TV-LCBI), maximum LCBI in 4 mm (maxLCBI_4mm), and maximum plaque burden (PB) were evaluated using NIRS-IVUS. A vulnerable plaque was defined as a lipid-rich plaque (maxLCBI4_mm ≥ 400) with large PB (≥ 70%). A total of 59 vessels of 45 patients were included. Median FFR value was 0.75 [interquartile 0.72, 0.82]. An FFR value of ≤ 0.80 was observed in 42 vessels (71%). TV-LCBI (correlation coefficient [CC] = - 0.331, p = 0.011), lesion length (CC = - 0.350, p = 0.007), and PB (CC = - 0.230, p = 0.080) negatively correlated with FFR value, while maxLCBI_4mm did not (CC = - 0.156, p = 0.24). The prevalence of vulnerable plaques (26.2% vs. 29.4%, p > 0.99) and mean TV-LCBI, maxLCBI_4mm, and PB values were not significantly different between the vessels with FFR ≤ 0.80 and those with FFR > 0.80. In multivariable logistic models, diabetes mellitus (p = 0.003) and hemoglobin A1c (p = 0.012) were associated with the presence of a vulnerable plaque. In conclusion, the results of the present study suggested that FFR may reflect total lipid burden but not necessarily plaque vulnerability. In patients with coronary artery disease and a high likelihood of rapid atherosclerosis progression, such as diabetes mellitus patients, assessing plaque vulnerability in addition to the functional severity of coronary artery lesions may help stratify better the risk of future events.

Cardiac MR: From Theory to Practice

Cardiovascular disease (CVD) is the leading single cause of morbidity and mortality, causing over 17. 9 million deaths worldwide per year with associated costs of over $800 billion. Improving prevention, diagnosis, and treatment of CVD is therefore a global priority. Cardiovascular magnetic resonance (CMR) has emerged as a clinically important technique for the assessment of cardiovascular anatomy, function, perfusion, and viability. However, diversity and complexity of imaging, reconstruction and analysis methods pose some limitations to the widespread use of CMR. Especially in view of recent developments in the field of machine learning that provide novel solutions to address existing problems, it is necessary to bridge the gap between the clinical and scientific communities. This review covers five essential aspects of CMR to provide a comprehensive overview ranging from CVDs to CMR pulse sequence design, acquisition protocols, motion handling, image reconstruction and quantitative analysis of the obtained data. (1) The basic MR physics of CMR is introduced. Basic pulse sequence building blocks that are commonly used in CMR imaging are presented. Sequences containing these building blocks are formed for parametric mapping and functional imaging techniques. Commonly perceived artifacts and potential countermeasures are discussed for these methods. (2) CMR methods for identifying CVDs are illustrated. Basic anatomy and functional processes are described to understand the cardiac pathologies and how they can be captured by CMR imaging. (3) The planning and conduct of a complete CMR exam which is targeted for the respective pathology is shown. Building blocks are illustrated to create an efficient and patient-centered workflow. Further strategies to cope with challenging patients are discussed. (4) Imaging acceleration and reconstruction techniques are presented that enable acquisition of spatial, temporal, and parametric dynamics of the cardiac cycle. The handling of respiratory and cardiac motion strategies as well as their integration into the reconstruction processes is showcased. (5) Recent advances on deep learning-based reconstructions for this purpose are summarized. Furthermore, an overview of novel deep learning image segmentation and analysis methods is provided with a focus on automatic, fast and reliable extraction of biomarkers and parameters of clinical relevance.

Diagnosis and Treatment of Acute Coronary Syndromes: A Review

IMPORTANCE

Acute coronary syndromes (ACS) are characterized by a sudden reduction in blood supply to the heart and include ST-segment elevation myocardial infarction (STEMI), non-STEMI (NSTEMI), and unstable angina. Each year, an estimated more than 7 million people in the world are diagnosed with ACS, including more than 1 million patients hospitalized in the US.

OBSERVATIONS

Chest discomfort at rest is the most common presenting symptom of ACS and affects approximately 79% of men and 74% of women presenting with ACS, although approximately 40% of men and 48% of women present with nonspecific symptoms, such as dyspnea, either in isolation or, more commonly, in combination with chest pain. For patients presenting with possible ACS, electrocardiography should be performed immediately (within 10 minutes of presentation) and can distinguish between STEMI and non-ST-segment elevation ACS (NSTE-ACS). STEMI is caused by complete coronary artery occlusion and accounts for approximately 30% of ACS. ACS without significant ST-segment elevation on electrocardiography, termed NSTE-ACS, account for approximately 70% of ACS, are caused by partial or intermittent occlusion of the artery and are associated with ST-segment depressions (approximately 31%), T-wave inversions (approximately 12%), ST-segment depressions combined with T-wave inversions (16%), or neither (approximately 41%). When electrocardiography suggests STEMI, rapid reperfusion with primary percutaneous coronary intervention (PCI) within 120 minutes reduces mortality from 9% to 7%. If PCI within 120 minutes is not possible, fibrinolytic therapy with alteplase, reteplase, or tenecteplase at full dose should be administered for patients younger than 75 years without contraindications and at half dose for patients 75 years or older (or streptokinase at full dose if cost is a consideration), followed by transfer to a facility with the goal of PCI within the next 24 hours. High-sensitivity troponin measurements are the preferred test to evaluate for NSTEMI. In high-risk patients with NSTE-ACS and no contraindications, prompt invasive coronary angiography and percutaneous or surgical revascularization within 24 to 48 hours are associated with a reduction in death from 6.5% to 4.9%.

CONCLUSIONS AND RELEVANCE

Each year, an estimated more than 7 million people are diagnosed with ACS worldwide. For patients with STEMI, coronary catheterization and PCI within 2 hours of presentation reduces mortality, with fibrinolytic therapy reserved for patients without access to immediate PCI. For high-risk patients with NSTE-ACS without contraindications, prompt invasive coronary angiography followed by percutaneous or surgical revascularization is associated with lower rates of death.

The Role of Antiplatelet Therapy in Patients With MINOCA

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous group of clinical entities characterized by the common clinical evidence of myocardial infarction (MI) with non-obstructive coronary arteries on coronary angiography and without an overt cause for the MI. Platelets play a cornerstone role in the pathophysiology of MI with obstructive coronary arteries. Accordingly, antiplatelet therapy is recommended for treating patients with MI and obstructive coronary disease. However, the role of platelets in the pathophysiology of MINOCA patients is not fully defined, questioning the role of antiplatelet therapy in this setting. In this review, we will assess the role of antiplatelet therapy in MINOCA with a focus on the pathophysiology, therapeutic targets, current evidence, and future directions according to its different etiologies.

Comparing methods of adenosine administration in paroxysmal supraventricular tachycardia: a pilot randomized controlled trial

Background

Intravenous adenosine is the recommended treatment for paroxysmal supraventricular tachycardia (PSVT). There is no official recommended method of giving adenosine. We compared the success rates between a standard and alternative method of first dose intravenous adenosine in PSVT.

Methods

A pilot parallel randomized controlled study was conducted in the emergency department of a tertiary care hospital. Eligible patients were stable PSVT adult patients. We used block randomization and divided them into two groups, the standard method (double syringe technique of 6 mg of adenosine), and the alternative method (similar to the standard method, then immediately followed by elevating the arm to 90° perpendicular to a horizontal plane for 10 s). The primary outcome was the success rate of electrocardiogram (ECG) response which demonstrated termination of PSVT (at least two-fold of the RR-interval widening or sinus rhythm conversion). Secondary outcomes were complications within one minute after the injection.

Results

We allocated 15 patients in each group and analyzed them as intention-to-treat. The success rate was 86.7% in the alternative group and 80% in the standard group (risk difference 6.7%, 95% confidence interval − 19.9 to 33.2%, P 1.00). Complications within one minute after adenosine injection were also similar in both groups, 14 of 15 patients (93%) in each group had no complications, without significant difference.

Conclusions

No evidence of the difference between alternative and standard methods occurred, in terms of the success rate of ECG response and complications within one minute after adenosine injection. The standard method of adenosine injection is a safe, easy-to-administer, and widely available treatment for PSVT.

Trial Registration: TCTR20200609001.

Evidence base for the management of women with non-ST elevation acute coronary syndrome

According to the Global Burden of Disease study, in 2019, there were an estimated 275.2 million cases of cardiovascular disease (CVD) in women worldwide. Although there was a decrease in the global age-standardised prevalence of CVD in women between 1990 and 2010 (–5.8%), there has been a slight increase (1.0%) since 2010. There were an estimated 6.10 million deaths from CVD in women in 1990, rising to 8.94 million in 2019. Hospital admissions of young women with acute myocardial infarction (AMI) steadily increased from 27% in 1995–1999 to 32% in 2010–2014. Women with AMI compared with men are less likely to receive guideline-indicated pharmacological (aspirin 93.4% vs 94.7%, P2Y12 inhibitors 79.3% vs 86.1% and statins 73.7% vs 77.5%) and revascularisation treatments (angiography (adjusted OR (aOR) 0.71), percutaneous coronary intervention (aOR 0.73)). Women represent <39% of clinical cardiovascular trial participants between 2010 and 2017. Major factors of under-representation in studies included concerns about the burden of participation on health and time. Women were more likely than men to document caring responsibilities as reasons for not participating in a clinical trial. Current clinical practice guidelines recommending risk stratification to guide the appropriateness of an invasive strategy in the context of acute coronary syndrome (ACS) may not be applicable to women given lack of studies specifically evaluating women using contemporary treatment strategies. In our review, we identify significant limitations in the evidence base for the best care of women with ACS, emphasising the need for well-designed clinical trials specifically recruiting women.

Gender-Disparities in the in-Hospital Clinical Outcome Among Patients with Chronic Kidney Disease Undergoing Percutaneous Coronary Intervention

PURPOSE

The current study was to evaluate the gender-disparities in the in-hospital thrombotic and bleeding events among patients with chronic kidney disease (CKD) undergoing percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

Patients with CKD undergoing PCI were retrospectively enrolled. Baseline characteristics, and thrombotic and bleeding events occurred during hospitalization were collected and compared by gender.

RESULTS

Compared to males (n = 558), females (n = 402) were older and more likely to have diabetes mellitus (37.1% vs 29.7%). Females had a lower estimated glomerular filtration rate (eGFR; 51.2 ± 7.9 vs 54.6 ± 5.1 mL/min/1.73m2) and were more likely to undergo urgent PCI (66.7% vs 60.2%) and use glycoprotein IIb/IIIa inhibitor (15.4% vs 7.5%) at peri-PCI period. Compared to males, females had a higher rate of in-hospital mortality which was due to thrombotic events (9.0% vs 3.4%). Females also had a higher rate of moderate-to-severe hemorrhage (8.0% vs 3.2%). After multivariable adjustment, diabetes mellitus (odds ratio [OR] 1.15 and 95% confidence interval [CI] 1.07-1.29) and acute coronary syndrome (ACS) presentation (OR 1.53 and 95% CI 1.34-1.93) were associated with gender-disparities in composite thrombotic events. Ageing (OR 1.10 and 95% CI 1.02-1.33), diabetes mellitus (OR 1.21 and 95% CI 1.07-1.40) and glycoprotein IIb/IIIa inhibitor use (OR 1.13 and 95% CI 1.02-1.28) were associated with composite bleeding events.

CONCLUSION

Females with CKD undergoing PCI had a higher risk of experiencing in-hospital thrombotic and bleeding events than males.

Feasibility of adenosine stress cardiovascular magnetic resonance perfusion imaging in patients with MR-conditional transvenous permanent pacemakers and defibrillators

BACKGROUND

The use of stress perfusion-cardiovascular magnetic resonance (CMR) imaging remains limited in patients with implantable devices. The primary goal of the study was to assess the safety, image quality, and the diagnostic value of stress perfusion-CMR in patients with MR-conditional transvenous permanent pacemakers (PPM) or implantable cardioverter-defibrillators (ICD).

METHODS

Consecutive patients with a transvenous PPM or ICD referred for adenosine stress-CMR were enrolled in this single-center longitudinal study. The CMR protocol was performed using a 1.5 T system according to current guidelines while all devices were put in MR-mode. Quality of cine, late-gadolinium-enhancement (LGE), and stress perfusion sequences were assessed. An ischemia burden of ≥ 1.5 segments was considered significant. We assessed the safety, image quality and the occurrence of interference of the magnetic field with the implantable device. In case of ischemia, we also assessed the correlation with the presence of significant coronary lesions on coronary angiography.

RESULTS

Among 3743 perfusion-CMR examinations, 66 patients had implantable devices (1.7%). Image quality proved diagnostic in 98% of cases. No device damage or malfunction was reported immediately and at 1 year. Fifty patients were continuously paced during CMR. Heart rate and systolic blood pressure remained unchanged during adenosine stress, while diastolic blood pressure decreased (p = 0.007). Six patients (9%) had an ischemia-positive stress CMR and significant coronary stenoses were confirmed by coronary angiography in all cases.

CONCLUSION

Stress perfusion-CMR is safe, allows reliable ischemia detection, and provides good diagnostic value.

Cardiac MRI Assessment of Nonischemic Myocardial Inflammation: State of the Art Review and Update on Myocarditis Associated with COVID-19 Vaccination

Myocarditis is a nonischemic inflammatory disease of the myocardium that can be triggered by a multitude of events, including viral infection and toxins. Recently, there has been heightened interest in myocarditis given its association with COVID-19 vaccination. Timely identification of myocarditis can affect patient management and prognosis. Therefore, it is crucial for radiologists and cardiac imagers to understand the role of cardiac imaging to establish a diagnosis and inform treatment decisions. Cardiac MRI is the most important noninvasive imaging modality for evaluation of myocarditis, with typical findings of focal or diffuse myocardial edema and myocardial damage, including presence of late gadolinium enhancement. There are currently limited data available to indicate that the pattern of myocardial injury following COVID-19 vaccination is similar to other causes of myocarditis, although the severity of disease may be relatively mild. A description of the role of imaging and typical imaging features will be reviewed here, with a focus on emerging data in the setting of myocarditis after COVID-19 vaccination. Keywords: MRI, Heart, Inflammation © RSNA, 2021.