Splenic Switch-Off for Determining the Optimal Dosage for Adenosine Stress Cardiac MR in Terms of Stress Effectiveness and Patient Safety.

BACKGROUND: Adenosine stress MRI is well established for the evaluation of known and suspected coronary artery disease. However, a proportion of patients might be "under-stressed" using the standard adenosine dose. PURPOSE: To compare three different adenosine dosages for stress MRI in terms of stress adequacy based on splenic switch-off (SSO) and limiting side effects. STUDY TYPE: Prospective. POPULATION: In all, 100 patients were randomized in group 1 (33 pts), group 2 (34 pts), and group 3 (33 pts), receiving dosages of 140 µg/kg/min, 175 µg/kg/min, or 210 µg/kg/min, respectively. SSO was evaluated visually and quantitatively. SEQUENCE: Stress perfusion was performed using a 1.5T scanner in three short axes using a standard single-shot, saturation recovery gradient-echo sequence. ASSESSMENT: Three blinded experienced operators evaluated SSO on stress and rest perfusion acquisitions in the three groups. The signal intensity of the spleen and myocardium and the presence of inducible ischemia and late gadolinium enhancement were assessed. STATISTICAL ANALYSIS: T-test, analysis of variance (ANOVA), chi-squared test, and Pearson's correlation coefficient. RESULTS: SSO was present more frequently in patients receiving 175 µg/kg/min and 210 µg/kg/min (31/33 [94%] and 27/29 [93%], respectively) compared to those receiving the standard dose (19/33 [58%], P < 0.05). A positive stress result was noted in 3/33 (9%) patients receiving 140 µg/kg/min vs. 9/33 (27%) patients receiving 175 µg/kg/min and 10/31 (33%) patients receiving 210 µg/kg/min (P < 0.05 for all, P < 0.05 for group 1 vs. groups 2, 3). The relative decrease of splenic signal intensity at hyperemia vs. baseline was significantly lower in group 1 compared to groups 2 and 3 (-33% vs. -54%, -56%, respectively; P < 0.05). No adverse events during scanning were noted in groups 1 and 2, whereas in group 3 four examinations were stopped due to severe dyspnea (n = 2) and AV-blockage (n = 2). DATA CONCLUSION: A dosage of 175 µg/kg/min adenosine results in a higher proportion of SSO, which may be an indirect marker of adequate coronary vasodilatation and simultaneously offers similar safety compared to the standard 140 µg/kg/min dosage. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2 J. MAGN. RESON. IMAGING 2020;52:1732-1742.

Case Report: Disappearance of Late Gadolinium Enhancement and Full Functional Recovery in a Young Patient With SARS-CoV-2 Vaccine-Related Myocarditis.

Acute myocarditis was recently demonstrated in previously healthy young male patients after receipt of mRNA SARS-CoV-2 vaccines. Herein, we report on a 21-year-old man who presented with acute fatigue, myalgia, and chest pain 2 days after his second SARS-CoV-2 vaccination with BNT162b2. Cardiac magnetic resonance (CMR) showed acute myocarditis, with mildly impaired LV-function and abundant subepicardial late gadolinium enhancement (LGE). Control CMR after 3 months showed full functional recovery and complete disappearance of LGE. The benefits of SARS-CoV-2 vaccination may significantly exceed the very rare and, in this case, fully reversible adverse effects.

Coronary Computer Tomography Angiography in 2021-Acquisition Protocols, Tips and Tricks and Heading beyond the Possible.

Recent technological advances, together with an increasing body of evidence from randomized trials, have placed coronary computer tomography angiography (CCTA) in the center of the diagnostic workup of patients with coronary artery disease. The method was proven reliable in the diagnosis of relevant coronary artery stenosis. Furthermore, it can identify different stages of the atherosclerotic process, including early atherosclerotic changes of the coronary vessel wall, a quality not met by other non-invasive tests. In addition, newer computational software can measure the hemodynamic relevance (fractional flow reserve) of a certain stenosis. In addition, if required, information related to cardiac and valvular function can be provided with specific protocols. Importantly, recent trials have highlighted the prognostic relevance of CCTA in patients with coronary artery disease, which helped establishing CCTA as the first-line method for the diagnostic work-up of such patients in current guidelines. All this can be gathered in one relatively fast examination with minimal discomfort for the patient and, with newer machines, with very low radiation exposure. Herein, we provide an overview of the current technical aspects, indications, pitfalls, and new horizons with CCTA, providing examples from our own clinical practice.

Diagnostic Work-Up of Cardiac Amyloidosis Using Cardiovascular Imaging: Current Standards and Practical Algorithms.

Among non-ischemic cardiomyopathies, cardiac amyloidosis is one of the most common, being caused by extracellular depositions of amyloid fibrils in the myocardium. Two main forms of cardiac amyloidosis are known so far, including 1) light-chain (AL) amyloidosis caused by monoclonal production of light-chains, and 2) transthyretin (ATTR) amyloidosis, caused by dissociation of the transthyretin tetramer into monomers. Both AL and ATTR amyloidosis are progressive diseases with median survival from diagnosis of less than 6 months and 3 to 5 years, respectively, if untreated. In this regard, death occurs in most patients due to cardiac causes, mainly congestive heart failure, which can be prevented due to the presence of effective, life-saving treatment regimens. Therefore, early diagnosis of cardiac amyloidosis is crucial more than ever. However, diagnosis of cardiac amyloidosis may be challenging due to variable clinical manifestations and the perceived rarity of the disease. In this regard, clinical and laboratory reg flags are available, which may help clinicians to raise suspicion of cardiac amyloidosis. In addition, advances in cardiovascular imaging have already revealed a higher prevalence of cardiac amyloidosis in specific populations, so that the diagnosis especially of ATTR amyloidosis has experienced a >30-fold increase during the past ten years. The goal of our review article is to summarize these findings and provide a practical approach for clinicians on how to use cardiovascular imaging techniques, such as echocardiography, cardiac magnetic resonance, bone scintigraphy and, if required, organ biopsy within predefined diagnostic algorithms for the diagnostic work-up of patients with suspected cardiac amyloidosis. In addition, two clinical cases and practical tips are provided in this context.

Aborted Sudden Cardiac Death in a Female Patient Presenting with Takotsubo-Like Cardiomyopathy due to Epicardial Coronary Vasospasm.

Takotsubo cardiomyopathy is characterized by apical ballooning of the left ventricle (LV) in the absence of relevant coronary artery stenosis, which typically occurs in elderly women after emotional stress. Catecholamine cardiotoxicity, metabolic disturbance, and coronary microvascular impairment have previously been proposed as underlying pathophysiologic mechanisms of takotsubo cardiomyopathy, whereas myocardial stunning resulting from epicardial coronary artery vasospasm is not generally accepted as a cause of takotsubo cardiomyopathy. The prognosis of takotsubo cardiomyopathy is generally more favourable compared to myocardial infarction; however, severe complications such as rupture of the LV and life-threatening arrhythmias may occur. Herein, we describe a case of an 84-year-old female, who presented with aborted sudden cardiac death due to ventricular fibrillation. Echocardiography suggested LV apical ballooning with severely impaired LV-function, so that takotsubo cardiomyopathy was suspected. However, coronary angiography revealed epicardial spasm of the left anterior ascending, which resolved after intracoronary injection of 0.2 mg nitroglycerine. Cardiac magnetic resonance exhibited subendocardial late enhancement and echocardiography showed normalization of LV dysfunction during follow-up. The patient was put on conservative treatment with nitrates and calcium inhibitors and ICD implantation were deferred.

Severe Left Ventricular Hypertrophy, Small Pericardial Effusion, and Diffuse Late Gadolinium Enhancement by Cardiac Magnetic Resonance Suspecting Cardiac Amyloidosis: Endomyocardial Biopsy Reveals an Unexpected Diagnosis.

Left ventricular (LV) hypertrophy can be related to a multitude of cardiac disorders, such as hypertrophic cardiomyopathy (HCM), cardiac amyloidosis, and hypertensive heart disease. Although the presence of LV hypertrophy is generally associated with poorer cardiac outcomes, the early differentiation between these pathologies is crucial due to the presence of specific treatment options. The diagnostic process with LV hypertrophy requires the integration of clinical evaluation, electrocardiography (ECG), echocardiography, biochemical markers, and if required CMR and endomyocardial biopsy in order to reach the correct diagnosis. Here, we present a case of a patient with severe LV hypertrophy (septal wall thickness of 23 mm, LV mass of 264 g, and LV mass index of 147 g/m(2)), severely impaired longitudinal function, and preserved radial contractility (ejection fraction = 55%), accompanied by small pericardial effusion and diffuse late gadolinium enhancement (LGE) by cardiac magnetic resonance (CMR). Due to the imaging findings, an infiltrative cardiomyopathy, such as cardiac amyloidosis, was suspected. However, amyloid accumulation was excluded by endomyocardial biopsy, which revealed the presence of diffuse myocardial fibrosis in an advanced hypertensive heart disease.