Manganese-Enhanced Magnetic Resonance Imaging in Takotsubo Syndrome.

BACKGROUND: Takotsubo syndrome is an acute cardiac emergency characterized by transient left ventricular systolic dysfunction typically following a stressful event. Despite its rapidly rising incidence, its pathophysiology remains poorly understood. Takotsubo syndrome may pass unrecognized, especially if timely diagnostic imaging is not performed. Defective myocardial calcium homeostasis is a central cause of contractile dysfunction and has not been explored in takotsubo syndrome. We aimed to investigate myocardial calcium handling using manganese-enhanced magnetic resonance imaging during the acute and recovery phases of takotsubo syndrome. METHODS: Twenty patients with takotsubo syndrome (63±12 years of age; 90% female) and 20 volunteers matched on age, sex, and cardiovascular risk factors (59±11 years of age; 70% female) were recruited from the Edinburgh Heart Centre between March 2020 and October 2021. Patients underwent gadolinium and manganese-enhanced magnetic resonance imaging during index hospitalization with repeat manganese-enhanced magnetic resonance imaging performed after at least 3 months. RESULTS: Compared with matched control volunteers, patients had a reduced left ventricular ejection fraction (51±11 versus 67±8%; P<0.001), increased left ventricular mass (86±11 versus 57±14 g/m2; P<0.001), and, in affected myocardial segments, elevated native T1 (1358±49 versus 1211±28 ms; P<0.001) and T2 (60±7 versus 38±3 ms; P<0.0001) values at their index presentation. During manganese-enhanced imaging, kinetic modeling demonstrated a substantial reduction in myocardial manganese uptake (5.1±0.5 versus 8.2±1.1 mL/[100 g of tissue ·min], respectively; P<0.0001), consistent with markedly abnormal myocardial calcium handling. After recovery, left ejection fraction, left ventricular mass, and T2 values were comparable with those of matched control volunteers. Despite this, native and postmanganese T1 and myocardial manganese uptake remained abnormal compared with matched control volunteers (6.6±0.5 versus 8.2±1.1 mL/[100 g of tissue ·min]; P<0.0001). CONCLUSIONS: In patients with takotsubo syndrome, there is a profound perturbation of myocardial manganese uptake, which is most marked in the acute phase but persists for at least 3 months despite apparent restoration of normal left ventricular ejection fraction and resolution of myocardial edema, suggesting abnormal myocardial calcium handling may be implicated in the pathophysiology of takotsubo syndrome. Manganese-enhanced magnetic resonance imaging has major potential to assist in the diagnosis, characterization, and risk stratification of patients with takotsubo syndrome. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04623788.

Myocardial and Systemic Inflammation in Acute Stress-Induced (Takotsubo) Cardiomyopathy.

BACKGROUND: Acute stress-induced (takotsubo) cardiomyopathy can result in a heart failure phenotype with a prognosis comparable with that of myocardial infarction. In this study, we hypothesized that inflammation is central to the pathophysiology and natural history of takotsubo cardiomyopathy. METHODS: In a multicenter study, we prospectively recruited 55 patients with takotsubo cardiomyopathy and 51 age-, sex-, and comorbidity-matched control subjects. During the index event and at the 5-month follow-up, patients with takotsubo cardiomyopathy underwent multiparametric cardiac magnetic resonance imaging, including ultrasmall superparamagnetic particles of iron oxide (USPIO) enhancement for detection of inflammatory macrophages in the myocardium. Blood monocyte subpopulations and serum cytokines were assessed as measures of systemic inflammation. Matched control subjects underwent investigation at a single time point. RESULTS: Subjects were predominantly middle-aged (64±14 years) women (90%). Compared with control subjects, patients with takotsubo cardiomyopathy had greater USPIO enhancement (expressed as the difference between pre-USPIO and post-USPIO T2*) in both ballooning (14.3±0.6 milliseconds versus 10.5±0.9 milliseconds; P<0.001) and nonballooning (12.9±0.6 milliseconds versus 10.5±0.9 milliseconds; P=0.02) left ventricular myocardial segments. Serum interleukin-6 (23.1±4.5 pg/mL versus 6.5±5.8 pg/mL; P<0.001) and chemokine (C-X-C motif) ligand 1 (1903±168 pg/mL versus 1272±177 pg/mL; P=0.01) concentrations and classic CD14++CD16- monocytes (90±0.5% versus 87±0.9%; P=0.01) were also increased whereas intermediate CD14++CD16+ (5.4±0.3% versus 6.9±0.6%; P=0.01) and nonclassic CD14+CD16++ (2.7±0.3% versus 4.2±0.5%; P=0.006) monocytes were reduced in patients with takotsubo cardiomyopathy. At 5 months, USPIO enhancement was no longer detectable in the left ventricular myocardium, although persistent elevations in serum interleukin-6 concentrations ( P=0.009) and reductions in intermediate CD14++CD16+ monocytes (5.6±0.4% versus 6.9±0.6%; P=0.01) remained. CONCLUSIONS: We demonstrate for the first time that takotsubo cardiomyopathy is characterized by a myocardial macrophage inflammatory infiltrate, changes in the distribution of monocyte subsets, and an increase in systemic proinflammatory cytokines. Many of these changes persisted for at least 5 months, suggesting a low-grade chronic inflammatory state. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02897739.

Persistent Long-Term Structural, Functional, and Metabolic Changes After Stress-Induced (Takotsubo) Cardiomyopathy.

BACKGROUND: Takotsubo cardiomyopathy is an increasingly recognized acute heart failure syndrome precipitated by intense emotional stress. Although there is an apparent rapid and spontaneous recovery of left ventricular ejection fraction, the long-term clinical and functional consequences of takotsubo cardiomyopathy are ill-defined. METHODS: In an observational case-control study, we recruited 37 patients with prior (>12-month) takotsubo cardiomyopathy, and 37 age-, sex-, and comorbidity-matched control subjects. Patients completed the Minnesota Living with Heart Failure Questionnaire. All participants underwent detailed clinical phenotypic characterization, including serum biomarker analysis, cardiopulmonary exercise testing, echocardiography, and cardiac magnetic resonance including cardiac 31P-spectroscopy. RESULTS: Participants were predominantly middle-age (64±11 years) women (97%). Although takotsubo cardiomyopathy occurred 20 (range 13-39) months before the study, the majority (88%) of patients had persisting symptoms compatible with heart failure (median of 13 [range 0-76] in the Minnesota Living with Heart Failure Questionnaire) and cardiac limitation on exercise testing (reduced peak oxygen consumption, 24±1.3 versus 31±1.3 mL/kg/min, P<0.001; increased VE/Vco2 slope, 31±1 versus 26±1, P=0.002). Despite normal left ventricular ejection fraction and serum biomarkers, patients with prior takotsubo cardiomyopathy had impaired cardiac deformation indices (reduced apical circumferential strain, -16±1.0 versus -23±1.5%, P<0.001; global longitudinal strain, -17±1 versus -20±1%, P=0.006), increased native T1 mapping values (1264±10 versus 1184±10 ms, P<0.001), and impaired cardiac energetic status (phosphocreatine/γ-adenosine triphosphate ratio, 1.3±0.1 versus 1.9±0.1, P<0.001). CONCLUSIONS: In contrast to previous perceptions, takotsubo cardiomyopathy has long-lasting clinical consequences, including demonstrable symptomatic and functional impairment associated with persistent subclinical cardiac dysfunction. Taken together our findings demonstrate that after takotsubo cardiomyopathy, patients develop a persistent, long-term heart failure phenotype. CLINICAL TRIAL REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: NCT02989454.

Reference range determination for imaging biomarkers: Myocardial T1.

BACKGROUND: Imaging biomarkers, such as the T1 relaxation time of the myocardium using MRI, can be valuable in cardiac medicine if they are properly validated. Consensus statements recommend that for myocardial T1 , each investigator should establish a reference range. PURPOSE: To describe a statistically valid method for determining and reporting the reference range in each center, which simultaneously minimizes the twin risks of undersampling, leading to a uselessly uncertain range, and oversampling, which exposes volunteers to unnecessary scanning and wastes resources. STUDY TYPE: Cohort. POPULATION: In all, 278 normal human subjects without cardiac disease from two cardiac MR centers. FIELD STRENGTH/SEQUENCE: 1.5 T and 3 T; Modified Look-Locker Inversion recovery sequence. ASSESSMENT: The T1 relaxation time was estimated from multiple samples of tissue magnetization after inversion. A valid method for calculating a reference range was used. STATISTICAL TESTS: Shapiro-Wilk test for normality; Tukey robust approach for identification of outliers; reference range calculation with confidence intervals. RESULTS: Reference ranges for measurement of myocardial T1 were calculated, with confidence intervals, enabling comparison with clinically important differences. At 3 T: 1129 to 1301 msec at site 1 (n = 21) and 1160 to 1309 msec at site 2 (n = 59), and at 1.5 T at site 2: 933 to 1020 msec (male, n = 130) and 965 to 1054 msec (female, n = 68). The 3 T reference range from site 1 was successfully benchmarked against the 3 T reference range at site 2. DATA CONCLUSION: Myocardial T1 reference ranges can be properly characterized, enabling clinical comparison to a valid reference range with known confidence intervals, using methodology similar to that described in this report. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 3 J. Magn. Reson. Imaging 2019;50:771-778.

Aortic stiffness in aortic stenosis assessed by cardiovascular MRI: a comparison between bicuspid and tricuspid valves.

OBJECTIVES: To compare aortic size and stiffness parameters on MRI between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) patients with aortic stenosis (AS). METHODS: MRI was performed in 174 patients with asymptomatic moderate-severe AS (mean AVAI 0.57 ± 0.14 cm2/m2) and 23 controls on 3T scanners. Valve morphology was available/analysable in 169 patients: 63 BAV (41 type-I, 22 type-II) and 106 TAV. Aortic cross-sectional areas were measured at the level of the pulmonary artery bifurcation. The ascending and descending aorta (AA, DA) distensibility, and pulse wave velocity (PWV) around the aortic arch were calculated. RESULTS: The AA and DA areas were lower in the controls, with no difference in DA distensibility or PWV, but slightly lower AA distensibility than in the patient group. With increasing age, there was a decrease in distensibility and an increase in PWV. After correcting for age, the AA maximum cross-sectional area was higher in bicuspid vs. tricuspid patients (12.97 [11.10, 15.59] vs. 10.06 [8.57, 12.04] cm2, p < 0.001), but there were no significant differences in AA distensibility (p = 0.099), DA distensibility (p = 0.498) or PWV (p = 0.235). Patients with BAV type-II valves demonstrated a significantly higher AA distensibility and lower PWV compared to type-I, despite a trend towards higher AA area. CONCLUSIONS: In patients with significant AS, BAV patients do not have increased aortic stiffness compared to those with TAV despite increased ascending aortic dimensions. Those with type-II BAV have less aortic stiffness despite greater dimensions. These results demonstrate a dissociation between aortic dilatation and stiffness and suggest that altered flow patterns may play a role. KEY POINTS: • Both cellular abnormalities secondary to genetic differences and abnormal flow patterns have been implicated in the pathophysiology of aortic dilatation and increased vascular complications associated with bicuspid aortic valves (BAV). • We demonstrate an increased ascending aortic size in patients with BAV and moderate to severe AS compared to TAV and controls, but no difference in aortic stiffness parameters, therefore suggesting a dissociation between dilatation and stiffness. • Sub-group analysis showed greater aortic size but lower stiffness parameters in those with BAV type-II AS compared to BAV type-I.

Comparison of exercise testing and CMR measured myocardial perfusion reserve for predicting outcome in asymptomatic aortic stenosis: the PRognostic Importance of MIcrovascular Dysfunction in Aortic Stenosis (PRIMID AS) Study.

AIMS: To assess cardiovascular magnetic resonance (CMR) measured myocardial perfusion reserve (MPR) and exercise testing in asymptomatic patients with moderate-severe AS. METHODS AND RESULTS: Multi-centre, prospective, observational study, with blinded analysis of CMR data. Patients underwent adenosine stress CMR, symptom-limited exercise testing (ETT) and echocardiography and were followed up for 12-30 months. The primary outcome was a composite of: typical AS symptoms necessitating referral for AVR, cardiovascular death and major adverse cardiovascular events. 174 patients were recruited: mean age 66.2 ± 13.34 years, 76% male, peak velocity 3.86 ± 0.56 m/s and aortic valve area index 0.57 ± 0.14 cm2/m2. A primary outcome occurred in 47 (27%) patients over a median follow-up of 374 (IQR 351-498) days. The mean MPR in those with and without a primary outcome was 2.06 ± 0.65 and 2.34 ± 0.70 (P = 0.022), while the incidence of a symptom-limited ETT was 45.7% and 27.0% (P = 0.020), respectively. MPR showed moderate association with outcome area under curve (AUC) = 0.61 (0.52-0.71, P = 0.020), as did exercise testing (AUC = 0.59 (0.51-0.68, P = 0.027), with no significant difference between the two. CONCLUSIONS: MPR was associated with symptom-onset in initially asymptomatic patients with AS, but with moderate accuracy and was not superior to symptom-limited exercise testing. ClinicalTrials.gov (NCT01658345).

Effect of Selective Heart Rate Slowing in Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is associated with significant morbidity and mortality but is currently refractory to therapy. Despite limited evidence, heart rate reduction has been advocated, on the basis of physiological considerations, as a therapeutic strategy in HFpEF. We tested the hypothesis that heart rate reduction improves exercise capacity in HFpEF. METHODS AND RESULTS: We conducted a randomized, crossover study comparing selective heart rate reduction with the If blocker ivabradine at 7.5 mg twice daily versus placebo for 2 weeks each in 22 symptomatic patients with HFpEF who had objective evidence of exercise limitation (peak oxygen consumption at maximal exercise [o2 peak] <80% predicted for age and sex). The result was compared with 22 similarly treated matched asymptomatic hypertensive volunteers. The primary end point was the change in o2 peak. Secondary outcomes included tissue Doppler-derived E/e' at echocardiography, plasma brain natriuretic peptide, and quality-of-life scores. Ivabradine significantly reduced peak heart rate compared with placebo in the HFpEF (107 versus 129 bpm; P<0.0001) and hypertensive (127 versus 145 bpm; P=0.003) cohorts. Ivabradine compared with placebo significantly worsened the change in o2 peak in the HFpEF cohort (-2.1 versus 0.9 mL·kg(-1)·min(-1); P=0.003) and significantly reduced submaximal exercise capacity, as determined by the oxygen uptake efficiency slope. No significant effects on the secondary end points were discernable. CONCLUSION: Our observations bring into question the value of heart rate reduction with ivabradine for improving symptoms in a HFpEF population characterized by exercise limitation. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02354573.

Sex-specific lifetime risk of cardiovascular events: the European Prospective Investigation into Cancer-Norfolk prospective population cohort study.

AIMS: Better understanding of sex differences in cardiovascular disease (CVD) is essential in tailoring appropriate preventative strategies. Using a large population-based study with follow-up >25 years, we aimed to determine sex-specific lifetime risks of incident CVD and cardiovascular (CV) mortality amongst populations with and without prevalent CVD. METHODS AND RESULTS: Participants were drawn from the European Prospective Investigation into Cancer-Norfolk and followed up for a median of 26.2 years. Sex-specific lifetime risks were ascertained accounting for the competing risk of death. Models were adjusted for ethnicity and time-updated covariates: material deprivation, CV risk factors, lifestyle factors, comorbidities, and medication. A total of 23 859 participants [54.5% women; mean age (standard deviation) 59.2 (9.3) years at baseline] were included. Adjusted lifetime risks of incident CVD were higher in men than in women (69.1 vs. 57.7% at age 75): cause-specific hazard ratio (cHR) (99% confidence interval)-1.49 (1.41-1.57), while the risks of CV mortality at age 75 were 4.4% (men) and 3.1% (women): cHR-1.42 (1.31-1.54). Myocardial infarction was the predominant first presentation in men until the eighth decade. In women, the first CVD manifestations after their sixth decade were predominantly atrial fibrillation and stroke. The male-associated excess relative risks of incident CVD and CV mortality were halved in people with prevalent CVD. CONCLUSION: We characterized the sex-specific lifetime CV risks in a large cohort. Men had substantially higher risk of incident CVD and CV mortality than women, which was attenuated amongst people with prevalent CVD. Our findings provide an evidence base for sex-specific CV prevention.

In this population-based study, we aimed to understand the sex-specific lifetime trajectories of different heart and circulatory disorders and their relationship with death from heart disease. We included ∼24 000 participants in the analyses, who were followed up for >25 years. Men had a higher lifetime risk of heart and circulatory disorders compared with women. Heart attacks were the predominant first presentation in men until the eighth decade, while in women this was manifested as heart rhythm disorders and stroke after their sixth decade. The excess risk of death from heart disease observed in men with pre-existing heart disease was attenuated compared with those free of heart disease at baseline. In conclusion, men and women require tailored heart disease prevention efforts given the marked sex disparities in heart disease and death over the very long-term highlighted by our study.

Cardiovascular and Noncardiovascular Prescribing and Mortality After Takotsubo Comparison With Myocardial Infarction and General Population.

Background: Takotsubo syndrome is an increasingly common cardiac emergency with no known evidence-based treatment. Objectives: The purpose of this study was to investigate cardiovascular mortality and medication use after takotsubo syndrome. Methods: In a case-control study, all patients with takotsubo syndrome in Scotland between 2010 and 2017 (n = 620) were age, sex, and geographically matched to individuals in the general population (1:4, n = 2,480) and contemporaneous patients with acute myocardial infarction (1:1, n = 620). Electronic health record data linkage of mortality outcomes and drug prescribing were analyzed using Cox proportional hazard regression models. Results: Of the 3,720 study participants (mean age, 66 years; 91% women), 153 (25%) patients with takotsubo syndrome died over the median of 5.5 years follow-up. This exceeded mortality rates in the general population (N = 374 [15%]; HR: 1.78 [95% CI: 1.48-2.15], P < 0.0001), especially for cardiovascular (HR: 2.47 [95% CI: 1.81-3.39], P < 0.001) but also noncardiovascular (HR: 1.48 [95% CI: 1.16-1.87], P = 0.002) deaths. Mortality rates were lower for patients with takotsubo syndrome than those with myocardial infarction (31%, 195/620; HR: 0.76 [95% CI: 0.62-0.94], P = 0.012), which was attributable to lower rates of cardiovascular (HR: 0.61 [95% CI: 0.44-0.84], P = 0.002) but not non-cardiovascular (HR: 0.92 [95% CI: 0.69-1.23], P = 0.59) deaths. Despite comparable medications use, cardiovascular therapies were consistently associated with better survival in patients with myocardial infarction but not in those with takotsubo syndrome. Diuretic (P = 0.01), anti-inflammatory (P = 0.002), and psychotropic (P < 0.001) therapies were all associated with worse outcomes in patients with takotsubo syndrome. Conclusions: In patients with takotsubo syndrome, cardiovascular mortality is the leading cause of death, and this is not associated with cardiovascular therapy use.

Coronary Atherosclerotic Plaque Activity and Risk of Myocardial Infarction.

BACKGROUND: Total coronary atherosclerotic plaque activity across the entire coronary arterial tree is associated with patient-level clinical outcomes. OBJECTIVES: We aimed to investigate whether vessel-level coronary atherosclerotic plaque activity is associated with vessel-level myocardial infarction. METHODS: In this secondary analysis of an international multicenter study of patients with recent myocardial infarction and multivessel coronary artery disease, we assessed vessel-level coronary atherosclerotic plaque activity using coronary 18F-sodium fluoride positron emission tomography to identify vessel-level myocardial infarction. RESULTS: Increased 18F-sodium fluoride uptake was found in 679 of 2,094 coronary arteries and 414 of 691 patients. Myocardial infarction occurred in 24 (4%) vessels with increased coronary atherosclerotic plaque activity and in 25 (2%) vessels without increased coronary atherosclerotic plaque activity (HR: 2.08; 95% CI: 1.16-3.72; P = 0.013). This association was not demonstrable in those treated with coronary revascularization (HR: 1.02; 95% CI: 0.47-2.25) but was notable in untreated vessels (HR: 3.86; 95% CI: 1.63-9.10; Pinteraction = 0.024). Increased coronary atherosclerotic plaque activity in multiple coronary arteries was associated with heightened patient-level risk of cardiac death or myocardial infarction (HR: 2.43; 95% CI: 1.37-4.30; P = 0.002) as well as first (HR: 2.19; 95% CI: 1.18-4.06; P = 0.013) and total (HR: 2.50; 95% CI: 1.42-4.39; P = 0.002) myocardial infarctions. CONCLUSIONS: In patients with recent myocardial infarction and multivessel coronary artery disease, coronary atherosclerotic plaque activity prognosticates individual coronary arteries and patients at risk for myocardial infarction.

Cardiac sarcoid or arrhythmogenic right ventricular cardiomyopathy: a role for positron emission tomography (PET)?

We present a case of cardiac sarcoidosis of insidious onset mimicking arrhythmogenic right ventricular cardiomyopathy. Our patient initially presented with systemic sarcoidosis but later developed palpitations. The similarity in clinical presentation and cardiac magnetic resonance findings in both conditions posed a challenge in differentiating between the two in the absence of histological diagnosis. We highlighted the role of positron emission tomography in aiding a diagnosis.

GPIb VNTR C/C genotype may predict embolic events in infective endocarditis.

BACKGROUND AND AIM OF THE STUDY: Infective endocarditis (IE) is frequently complicated by septic embolism, a need for valve replacement, and death. The development of these complications is associated with the presence, size and mobility of cardiac vegetations, which may form as a result of bacterium-platelet interactions mediated by the platelet glycoprotein GPIb receptor. Variable number tandem repeat (VNTR) and single nucleotide polymorphisms of the gene encoding the GPIb receptor have been described, but their correlation with platelet function, development of vegetations and complications of IE is unknown. METHODS: The GPIb Kozak T/C, VNTR and human platelet antigen-2a/2b (HPA-2a/2b) genotype of healthy volunteers (n = 156) and patients with IE (n = 35) was determined, and the influence of these polymorphisms on Staphylococcus aureus-induced platelet aggregation in vitro, platelet activation in vivo and clinical outcome in IE was then investigated. RESULTS: The GPIb VNTR C/C genotype was associated with an increased risk of embolism (p = 0.039), with no influence on platelet activation or aggregation, vegetation characteristics or mortality (p > 0.05 for all). The GPIb Kozak T/C and HPA-2a/2b polymorphisms did not influence the development of complications in patients with IE (all p > 0.05). CONCLUSION: The results of these exploratory studies suggest that the GPIb VNTR C/C genotype may predict the development of septic emboli in patients with IE. This hypothesis should be analyzed in larger studies and, if confirmed, would represent an important clinical finding, as it implies that early surgery in patients with the GPIb VNTR C/C genotype could reduce morbidity and mortality in IE.

Structural and Functional Brain Changes in Acute Takotsubo Syndrome.

BACKGROUND: Takotsubo syndrome mimics an acute myocardial infarction, typically in the aftermath of mental or physical stress. OBJECTIVES: The mechanism by which emotional processing in the context of stress leads to significant cardiac injury is poorly understood, so a full exploration of brain structure and function in takotsubo syndrome patients merits investigation. METHODS: Twenty-five acute (<5 days) takotsubo patients and 25 control subjects were recruited into this observational cross-sectional study. Surface-based morphometry was carried out on magnetic resonance imaging (MRI) brain scans to extract cortical morphology based on volume, thickness, and surface area with the use of Freesurfer. Cortical morphology general linear models were corrected for age, sex, photoperiod, and total brain volume. Resting-state functional MRI and diffusion tensor tractography images were preprocessed and analyzed with the use of the Functional Magnetic Resonance Imaging of the Brain Diffusion Toolbox and Functional Connectivity Toolbox. RESULTS: There was significantly smaller total white matter and subcortical gray matter volumes in takotsubo (P < 0.001), with smaller total brain surface area but increased total cortical thickness (both P < 0.001). Individual gray matter regions (hippocampus and others) were significantly smaller in takotsubo (P < 0.001); only thalamus and insula were larger (P < 0.001). There was significant hyperfunctional and hypofunctional connectivity in multiple areas, including thalamus-amygdala-insula and basal ganglia (P < 0.05). All structural tractography connections were increased in takotsubo (P < 0.05). CONCLUSIONS: The authors showed smaller gray and white matter volumes driven by smaller cortical surface area, but increased cortical thickness and structural tractography connections with bidirectional changes in functional connectivity linked to emotion, language, reasoning, perception, and autonomic control. These are interventional targets in takotsubo patients' rehabilitation.

Psilocybin-induced takotsubo cardiomyopathy.

We present a case of takotsubo cardiomyopathy following recreational ingestion of Psilocybe semilanceata (known as 'magic mushrooms'). The patient presented with respiratory distress and pulmonary oedema responding to standard medical measures. Investigations included: echocardiogram, cardiac MRI and angiogram. Based on our search, we suggest this is only the second recognised case in the published literature.

Renin-Angiotensin and Endothelin Systems in Patients Post-Takotsubo Cardiomyopathy.

Background We investigate if renin-angiotensin and endothelin-1 response pathways follow the same pattern of recovery as left ventricular ejection fraction in patients with takotsubo cardiomyopathy. Methods and Results Ninety patients with takotsubo cardiomyopathy (n=30 in each of "acute," "convalescent" [3-5 months] and "recovered" [>1 year] groups) who were on minimal or no medication and were free of any significant cardiac/metabolic comorbidities, and 30 controls were studied. Serum concentrations of renin, angiotensin-converting enzyme, angiotensin II, big endothelin-1, endothelin-1 were measured using commercially available ELISA, and B-type natriuretic peptide was measured using an immunoassay. Mean left ventricular ejection fraction was <40% during the acute phase in all groups, but recovered to 63% in convalescent and 64% in the recovered groups, respectively. Serum renin concentrations remain persistently elevated after a episode of takotsubo cardiomyopathy (P=0.03 versus controls). Angiotensin converting enzyme levels are significantly depressed during the acute phase compared with convalescent (P=0.004), recovered takotsubo cardiomyopathy (P=0.02) or controls (P=0.03). Angiotensin II is increased in patients with takotsubo cardiomyopathy (P<0.001 versus controls) remaining persistently elevated in the chronically recovered group alone (P=0.03 versus controls). Big endothelin-1 levels are unchanged, but endothelin-1 is significantly lower after takotsubo cardiomyopathy compared with controls (P=0.03). Conclusions Despite "normalization" of the left ventricular ejection fraction, there is long-term maladaptive activation of renin-angiotensin system in patients with takotsubo cardiomyopathy. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02897739, NCT02989454.

Metabolic alterations in a rat model of takotsubo syndrome.

AIMS: Cardiac energetic impairment is a major finding in takotsubo patients. We investigate specific metabolic adaptations to direct future therapies. METHODS AND RESULTS: An isoprenaline-injection female rat model (vs. sham) was studied at Day 3; recovery assessed at Day 7. Substrate uptake, metabolism, inflammation, and remodelling were investigated by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography, metabolomics, quantitative PCR, and western blot (WB). Isolated cardiomyocytes were patch-clamped during stress protocols for redox states of NAD(P)H/FAD or [Ca2+]c, [Ca2+]m, and sarcomere length. Mitochondrial respiration was assessed by seahorse/Clark electrode (glycolytic and ß-oxidation substrates). Cardiac 18F-FDG metabolic rate was increased in takotsubo (P = 0.006), as was the expression of GLUT4-RNA/GLUT1/HK2-RNA and HK activity (all P < 0.05), with concomitant accumulation of glucose- and fructose-6-phosphates (P > 0.0001). Both lactate and pyruvate were lower (P < 0.05) despite increases in LDH-RNA and PDH (P < 0.05 both). ß-Oxidation enzymes CPT1b-RNA and 3-ketoacyl-CoA thiolase were increased (P < 0.01) but malonyl-CoA (CPT-1 regulator) was upregulated (P = 0.01) with decreased fatty acids and acyl-carnitines levels (P = 0.0001-0.02). Krebs cycle intermediates α-ketoglutarate and succinyl-carnitine were reduced (P < 0.05) as was cellular ATP reporter dihydroorotate (P = 0.003). Mitochondrial Ca2+ uptake during high workload was impaired on Day 3 (P < 0.0001), inducing the oxidation of NAD(P)H and FAD (P = 0.03) but resolved by Day 7. There were no differences in mitochondrial respiratory function, sarcomere shortening, or [Ca2+] transients of isolated cardiomyocytes, implying preserved integrity of both mitochondria and cardiomyocyte. Inflammation and remodelling were upregulated-increased CD68-RNA, collagen RNA/protein, and skeletal actin RNA (all P < 0.05). CONCLUSION: Dysregulation of glucose and lipid metabolic pathways with decreases in final glycolytic and ß-oxidation metabolites and reduced availability of Krebs intermediates characterizes takotsubo myocardium. The energetic deficit accompanies defective Ca2+ handling, inflammation, and upregulation of remodelling pathways, with the preservation of sarcomeric and mitochondrial integrity.