Evaluating a Phase-Specific Approach to Aortic Flow: A 4D Flow MRI Study.

BACKGROUND: Aortic flow parameters can be quantified using 4D flow MRI. However, data are sparse on how different methods of analysis influence these parameters and how these parameters evolve during systole. PURPOSE: To assess multiphase segmentations and multiphase quantification of flow-related parameters in aortic 4D flow MRI. STUDY TYPE: Prospective. POPULATION: 40 healthy volunteers (50% male, 28.9 ± 5.0 years) and 10 patients with thoracic aortic aneurysm (80% male, 54 ± 8 years). FIELD STRENGTH/SEQUENCE: 4D flow MRI with a velocity encoded turbo field echo sequence at 3 T. ASSESSMENT: Phase-specific segmentations were obtained for the aortic root and the ascending aorta. The whole aorta was segmented in peak systole. In all aortic segments, time to peak (TTP; for flow velocity, vorticity, helicity, kinetic energy, and viscous energy loss) and peak and time-averaged values (for velocity and vorticity) were calculated. STATISTICAL TESTS: Static vs. phase-specific models were assessed using Bland-Altman plots. Other analyses were performed using phase-specific segmentations for aortic root and ascending aorta. TTP for all parameters was compared to TTP of flow rate using paired t-tests. Time-averaged and peak values were assessed using Pearson correlation coefficient. P < 0.05 was considered statistically significant. RESULTS: In the combined group, velocity in static vs. phase-specific segmentations differed by 0.8 cm/sec for the aortic root, and 0.1 cm/sec (P = 0.214) for the ascending aorta. Vorticity differed by 167 sec-1 mL-1 (P = 0.468) for the aortic root, and by 59 sec-1 mL-1 (P = 0.481) for the ascending aorta. Vorticity, helicity, and energy loss in the ascending aorta, aortic arch, and descending aorta peaked significantly later than flow rate. Time-averaged velocity and vorticity values correlated significantly in all segments. DATA CONCLUSION: Static 4D flow MRI segmentation yields comparable results as multiphase segmentation for flow-related parameters, eliminating the need for time-consuming multiple segmentations. However, multiphase quantification is necessary for assessing peak values of aortic flow-related parameters. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 3.

The Maastricht Acquisition Platform for Studying Mechanisms of Cell-Matrix Crosstalk (MAPEX): An Interdisciplinary and Systems Approach towards Understanding Thoracic Aortic Disease.

Current management guidelines for ascending thoracic aortic aneurysms (aTAA) recommend intervention once ascending or sinus diameter reaches 5-5.5 cm or shows a growth rate of >0.5 cm/year estimated from echo/CT/MRI. However, many aTAA dissections (aTAAD) occur in vessels with diameters below the surgical intervention threshold of <55 mm. Moreover, during aTAA repair surgeons observe and experience considerable variations in tissue strength, thickness, and stiffness that appear not fully explained by patient risk factors. To improve the understanding of aTAA pathophysiology, we established a multi-disciplinary research infrastructure: The Maastricht acquisition platform for studying mechanisms of tissue-cell crosstalk (MAPEX). The explicit scientific focus of the platform is on the dynamic interactions between vascular smooth muscle cells and extracellular matrix (i.e., cell-matrix crosstalk), which play an essential role in aortic wall mechanical homeostasis. Accordingly, we consider pathophysiological influences of wall shear stress, wall stress, and smooth muscle cell phenotypic diversity and modulation. Co-registrations of hemodynamics and deep phenotyping at the histological and cell biology level are key innovations of our platform and are critical for understanding aneurysm formation and dissection at a fundamental level. The MAPEX platform enables the interpretation of the data in a well-defined clinical context and therefore has real potential for narrowing existing knowledge gaps. A better understanding of aortic mechanical homeostasis and its derangement may ultimately improve diagnostic and prognostic possibilities to identify and treat symptomatic and asymptomatic patients with existing and developing aneurysms.

A clinician's guide to understanding aortic 4D flow MRI.

Four-dimensional flow magnetic resonance imaging is an emerging technique which may play a role in diagnosis and risk-stratification of aortic disease. Some knowledge of flow dynamics and related parameters is necessary to understand and apply this technique in clinical workflows. The purpose of the current review is to provide a guide for clinicians to the basics of flow imaging, frequently used flow-related parameters, and their relevance in the context of aortic disease.Clinical relevance statement Understanding normal and abnormal aortic flow could improve clinical care in patients with aortic disease.

Biomechanical Characterisation of Thoracic Ascending Aorta with Preserved Pre-Stresses.

Mechanical properties of an aneurysmatic thoracic aorta are potential markers of future growth and remodelling and can help to estimate the risk of rupture. Aortic geometries obtained from routine medical imaging do not display wall stress distribution and mechanical properties. Mechanical properties for a given vessel may be determined from medical images at different physiological pressures using inverse finite element analysis. However, without considering pre-stresses, the estimation of mechanical properties will lack accuracy. In the present paper, we propose and evaluate a mechanical parameter identification technique, which recovers pre-stresses by determining the zero-pressure configuration of the aortic geometry. We first validated the method on a cylindrical geometry and subsequently applied it to a realistic aortic geometry. The verification of the assessed parameters was performed using synthetically generated reference data for both geometries. The method was able to estimate the true mechanical properties with an accuracy ranging from 98% to 99%.

Editor's Choice - Extending Aortic Replacement Beyond the Proximal Arch in Acute Type A Aortic Dissection: A Meta-Analysis of Short Term Outcomes and Long Term Actuarial Survival.

OBJECTIVE: The extent of aortic replacement during surgery for acute type A aortic dissection (ATAAD) is an important matter of debate. This meta-analysis aimed to evaluate the short and long term outcomes of a proximal aortic repair (PAR) vs. total arch replacement (TAR) in the treatment of ATAAD. DATA SOURCES: A systematic search of PubMed and Embase was performed. Studies comparing PAR to TAR for ATAAD were included. REVIEW METHODS: The primary outcomes were early death and long term actuarial survival at one, five, and 10 years. Random effects models in conjunction with relative risks (RRs) were used for meta-analyses. RESULTS: Nineteen studies were included, comprising 5 744 patients (proximal: n = 4 208; total arch: n = 1 536). PAR was associated with reduced early mortality (10.8% [95% confidence interval (CI) 8.4 - 13.7] vs. 14.0% [95% CI 10.4 - 18.7]; RR 0.73 [95% CI 0.63 - 0.85]) and reduced post-operative renal failure (10.4% [95% CI 7.2 - 14.8] vs. 11.1% [95% CI 6.7 - 17.5]; RR 0.77 [95% CI 0.66 - 0.90]), but there was no difference in stroke (8.0% [95% CI 5.9 - 10.7] vs. 7.3% [95% CI 4.6 - 11.3]; RR 0.87 [95% CI 0.69 - 1.10]). No statistically significant difference was found for survival after one year (83.2% [95% CI 77.5 - 87.7] vs. 78.6% [95% CI 69.7 - 85.5]; RR 1.05 [95% CI 0.99 - 1.11]), which persisted after five years (75.4% [95% CI 71.2 - 79.2] vs. 74.5% [95% CI 64.7 - 82.3]; RR 1.02 [95% CI 0.91 - 1.14]). After 10 years, there was a significant survival benefit for patients who underwent TAR (64.7% [95% CI 61.1 - 68.1] vs. 72.4% [95% CI 67.5 - 76.7]; RR 0.91 [95% CI 0.84 - 0.99]). CONCLUSION: PAR appears to lead to an improved early mortality rate and a reduced complication rate. In the current meta-analysis, the suggestion of an improved 10 year survival benefit of TAR was found, which should be interpreted in the context of potential confounders such as age at presentation, comorbidities, and haemodynamic stability. In any case, PAR seems to be intuitive in older patients with limited dissections, and in those presenting in less stable conditions.

Long-Term Adherence to Direct Oral Anticoagulants in Patients with Atrial Fibrillation: A Comparative Cross-Sectional Study.

BACKGROUND: Long-term treatment with direct oral anticoagulants (DOAC) is required for the majority of patients with nonvalvular atrial fibrillation (AF) to prevent ischemic stroke and systemic embolism. Adherence to therapy may impact clinical outcomes. Therefore, the purpose of this study was to assess the potential impact of structured follow-up on long-term adherence to DOAC therapy compared to standard care. METHODS: This is a cross sectional study on the implementation phase of medication adherence to DOACs, comparing patients with AF following completion of structured follow-up of minimally 1 year with those who received standard care. All patients used DOACs for more than 2 years and completed a questionnaire on adherence. Adherence was measured with the Morisky Medication Adherence Scale-8 (MMAS-8) score and assessed via an online web portal. RESULTS: A total of 212 patients were included. The mean MMAS-8 score was 7.55 (SD 0.93) after structured follow-up and 7.25 (SD 1.01) for standard care; p = 0.045. Following structured follow-up 64.1% of patients had a high adherence (MMAS score of 8) compared to 50% receiving standard care; p = 0.05. Patients following structured follow-up on a once daily DOAC regime had higher MMAS-8 scores compared to those on a twice daily regime; 7.74 (SD 0.74) versus 7.00 (SD 1.22); p < 0.001. The rates of minor bleedings were 10.6% versus 21.4% respectively, p = 0.038. CONCLUSION: In patients on long-term DOAC treatment, adherence to therapy was significantly increased after receiving an initial period of structured follow-up compared to standard care. Additionally, adherence to DOAC therapy was higher with once-daily treatment regimen. Significant more minor bleedings were reported in the standard care group. These results indicate that implementation of structured follow-up of patients with AF using DOACs merits further evaluation.

Imaging surveillance for complications after primary surgery for type A aortic dissection.

Acute type A aortic dissection (ATAAD) is a life-threatening condition that requires emergency surgery to avert fatal outcome. Conventional surgical procedures comprise excision of the entry tear and replacement of the proximal aorta with a synthetic vascular graft. In patients with DeBakey type I dissection, this approach leaves a chronically dissected distal aorta, putting them at risk for progressive dilatation, dissection propagation and aortic rupture. Therefore, ATAAD survivors should undergo serial imaging for evaluation of the aortic valve, proximal and distal anastomoses, and the aortic segments beyond the distal anastomosis. The current narrative review aims to describe potential complications in the early and late phases after ATAAD surgery, with focus on their specific imaging findings.

Improving diagnosis and risk stratification across the ejection fraction spectrum: the Maastricht Cardiomyopathy registry.

AIMS: Heart failure (HF) represents a clinical syndrome resulting from different aetiologies and degrees of heart diseases. Among these, a key role is played by primary heart muscle disease (cardiomyopathies), which are the combination of multifactorial environmental insults in the presence or absence of a known genetic predisposition. The aim of the Maastricht Cardiomyopathy registry (mCMP-registry; NCT04976348) is to improve (early) diagnosis, risk stratification, and management of cardiomyopathy phenotypes beyond the limits of left ventricular ejection fraction (LVEF). METHODS AND RESULTS: The mCMP-registry is an investigator-initiated prospective registry including patient characteristics, diagnostic measurements performed as part of routine clinical care, treatment information, sequential biobanking, quality of life and economic impact assessment, and regular follow-up. All subjects aged ≥16 years referred to the cardiology department of the Maastricht University Medical Center (MUMC+) for HF-like symptoms or cardiac screening for cardiomyopathies are eligible for inclusion, irrespective of phenotype or underlying causes. Informed consented subjects will be followed up for 15 years. Two central approaches will be used to answer the research questions related to the aims of this registry: (i) a data-driven approach to predict clinical outcome and response to therapy and to identify clusters of patients who share underlying pathophysiological processes; and (ii) a hypothesis-driven approach in which clinical parameters are tested for their (incremental) diagnostic, prognostic, or therapeutic value. The study allows other centres to easily join this initiative, which will further boost research within this field. CONCLUSIONS: The broad inclusion criteria, systematic routine clinical care data-collection, extensive study-related data-collection, sequential biobanking, and multi-disciplinary approach gives the mCMP-registry a unique opportunity to improve diagnosis, risk stratification, and management of HF and (early) cardiomyopathy phenotypes beyond the LVEF limits.

Role of pre-operative transthoracic echocardiography in predicting post-operative atrial fibrillation after cardiac surgery: a systematic review of the literature and meta-analysis.

AIMS: This systematic review and meta-analysis aims to evaluate the role of pre-operative transthoracic echocardiography in predicting post-operative atrial fibrillation (POAF) after cardiac surgery. METHODS AND RESULTS: Electronic databases were searched for studies reporting on pre-operative echocardiographic predictors of POAF in PubMed, Cochrane library, and Embase. A meta-analysis of echocardiographic predictors of POAF that were identified by at least five different publications was performed. Forty-three publications were included in this systematic review. Echocardiographic predictors for POAF included surrogate parameters for total atrial conduction time (TACT), structural cardiac changes, and functional disturbances. Meta-analysis showed that prolonged pre-operative PA-TDI interval [5 studies, Cohen's d = 1.4, 95% confidence interval (CI) 0.9-1.9], increased left atrial volume indexed for body surface area (LAVI) (23 studies, Cohen's d = 0.8, 95% CI 0.6-1.0), and reduced peak atrial longitudinal strain (PALS) (5 studies, Cohen's d = 1.4, 95% CI 1.0-1.8), were associated with POAF incidence. Left atrial volume indexed for body surface was the most important predicting factor in patients without a history of AF. These parameters remained important predictors of POAF in heterogeneous populations with variable age and comorbidities such as coronary artery disease and valvular disease. CONCLUSION: This meta-analysis shows that increased TACT, increased LAVI, and reduced PALS are valuable parameters for predicting POAF in the early post-operative phase in a large variety of patients.

Cardiovascular magnetic resonance accurately detects obstructive coronary artery disease in suspected non-ST elevation myocardial infarction: a sub-analysis of the CARMENTA Trial.

BACKGROUND: Invasive coronary angiography (ICA) is still the reference test in suspected non-ST elevation myocardial infarction (NSTEMI), although a substantial number of patients do not have obstructive coronary artery disease (CAD). Early cardiovascular magnetic resonance (CMR) may be a useful gatekeeper for ICA in this setting. The main objective was to investigate the accuracy of CMR to detect obstructive CAD in NSTEMI. METHODS: This study is a sub-analysis of a randomized controlled trial investigating whether a non-invasive imaging-first strategy safely reduced the number of ICA compared to routine clinical care in suspected NSTEMI (acute chest pain, non-diagnostic electrocardiogram, high sensitivity troponin T > 14 ng/L), and included 51 patients who underwent CMR prior to ICA. A stepwise approach was used to assess the diagnostic accuracy of CMR to detect (1) obstructive CAD (diameter stenosis ≥ 70% by ICA) and (2) an adjudicated final diagnosis of acute coronary syndrome (ACS). First, in all patients the combination of cine, T2-weighted and late gadolinium enhancement (LGE) imaging was evaluated for the presence of abnormalities consistent with a coronary etiology in any sequence. Hereafter and only when the scan was normal or equivocal, adenosine stress-perfusion CMR was added. RESULTS: Of 51 patients included (63 ± 10 years, 51% male), 34 (67%) had obstructive CAD by ICA. The sensitivity, specificity and overall accuracy of the first step to diagnose obstructive CAD were 79%, 71% and 77%, respectively. Additional vasodilator stress-perfusion CMR was performed in 19 patients and combined with step one resulted in an overall sensitivity of 97%, specificity of 65% and accuracy of 86%. Of the remaining 17 patients with non-obstructive CAD, 4 (24%) had evidence for a myocardial infarction on LGE, explaining the modest specificity. The sensitivity, specificity and overall accuracy to diagnose ACS (n = 43) were 88%, 88% and 88%, respectively. CONCLUSION: CMR accurately detects obstructive CAD and ACS in suspected NSTEMI. Non-obstructive CAD is common with CMR still identifying an infarction in almost one-quarter of patients. CMR should be considered as an early diagnostic approach in suspected NSTEMI. TRIAL REGISTRATION: The CARMENTA trial has been registered at ClinicalTrials.gov with identifier NCT01559467.

Effect of a dedicated mitral heart team compared to a general heart team on survival: a retrospective, comparative, non-randomized interventional cohort study based on prospectively registered data.

OBJECTIVES: Although in both the US and European guidelines the 'heart team approach' is a class I recommendation, supporting evidence is still lacking. Therefore, we sought to provide comparative survival data of patients with mitral valve disease referred to the general and the dedicated heart team. METHODS: In this retrospective cohort, patients evaluated for mitral valve disease by a general heart team (2009-2014) and a dedicated mitral valve heart team (2014-2018) were included. Decision-making was recorded prospectively in heart team electronic forms. The end point was overall survival from decision of the heart team. RESULTS: In total, 1145 patients were included of whom 641 (56%) were discussed by dedicated heart team and 504 (44%) by general heart team. At 5 years, survival probability was 0.74 [95% confidence interval (CI) 0.68-0.79] for the dedicated heart team group compared to 0.70 (95% CI 0.66-0.74, P = 0.040) for the general heart team. Relative risk of mortality adjusted for EuroSCORE II, treatment groups (surgical, transcatheter and non-intervention), mitral valve pathology (degenerative, functional, rheumatic and others) and 13 other baseline characteristics for patients in the dedicated heart team was 29% lower [hazard ratio (HR) 0.71, 95% CI 0.54-0.95; P = 0.019] than for the general heart team. The adjusted relative risk of mortality was 61% lower for patients following the advice of the heart team (HR 0.39, 95% CI 0.25-0.62; P < 0.001) and 43% lower for patients following the advice of the general heart team (HR 0.57, 95% CI 0.37-0.87; P = 0.010) compared to those who did not follow the advice of the heart team. CONCLUSIONS: In this retrospective cohort, patients treated for mitral valve disease based on a dedicated heart team decision have significantly higher survival independent of the allocated treatment, mitral valve pathology and baseline characteristics.

Characterization of Ascending Aortic Flow in Patients With Degenerative Aneurysms: A 4D Flow Magnetic Resonance Study.

OBJECTIVES: Degenerative thoracic aortic aneurysm (TAA) patients are known to be at risk of life-threatening acute aortic events. Guidelines recommend preemptive surgery at diameters of greater than 55 mm, although many patients with small aneurysms show only mild growth rates and more than half of complications occur in aneurysms below this threshold. Thus, assessment of hemodynamics using 4-dimensional flow magnetic resonance has been of interest to obtain more insights in aneurysm development. Nonetheless, the role of aberrant flow patterns in TAA patients is not yet fully understood. MATERIALS AND METHODS: A total of 25 TAA patients and 22 controls underwent time-resolved 3-dimensional phase contrast magnetic resonance imaging with 3-directional velocity encoding (ie, 4-dimensional flow magnetic resonance imaging). Hemodynamic parameters such as vorticity, helicity, and wall shear stress (WSS) were calculated from velocity data in 3 anatomical segments of the ascending aorta (root, proximal, and distal). Regional WSS distribution was assessed for the full cardiac cycle. RESULTS: Flow vorticity and helicity were significantly lower for TAA patients in all segments. The proximal ascending aorta showed a significant increase in peak WSS in the outer curvature in TAA patients, whereas WSS values at the inner curvature were significantly lower as compared with controls. Furthermore, positive WSS gradients from sinotubular junction to midascending aorta were most prominent in the outer curvature, whereas from midascending aorta to brachiocephalic trunk, the outer curvature showed negative WSS gradients in the TAA group. Controls solely showed a positive gradient at the inner curvature for both segments. CONCLUSIONS: Degenerative TAA patients show a decrease in flow vorticity and helicity, which is likely to cause perturbations in physiological flow patterns. The subsequent differing distribution of WSS might be a contributor to vessel wall remodeling and aneurysm formation.

Evaluating the diagnostic accuracy of maximal aortic diameter, length and volume for prediction of aortic dissection.

OBJECTIVE: Management of thoracic aortic aneurysms (TAAs) comprises regular diameter follow-up until the indication criterion for prophylactic surgery is reached. However, this approach is unable to predict the majority of acute type A aortic dissections (ATAADs). The current study aims to evaluate the diagnostic accuracy of ascending aortic diameter, length and volume for occurrence of ATAAD. METHODS: This two-centre observational cohort study retrospectively screened 477 consecutive patients who presented with ATAAD between 2009 and 2018. Of those, 25 (5.2%) underwent CT angiography (CTA) within 2 years before dissection onset. Aortic diameter, length and volume of these patients ('pre-ATAAD') were compared with those of TAA controls (n=75). Receiver operating curve analysis was performed to evaluate the predictive accuracy of the three different measurements. RESULTS: 96% of patients with pre-ATAAD did not meet the surgical diameter threshold of 55 mm before dissection onset. Maximal aortic diameters (45 (40-49) mm vs 46 (44-49) mm, p=0.075) and volume (126 (95-157) cm3 vs 124 (102-136) cm3, p=0.909) were comparable between patients with pre-ATAAD and TAA controls. Conversely, ascending aortic length (84±9 mm vs 90±16 mm, p=0.031) was significantly larger in patients with pre-ATAAD. All three parameters had an area under the curve of >0.800. At the 55 mm cut-off point, the maximal diameter yielded a positive predictive value (PPV) of 20%. While maintaining same specificity levels, measurements of aortic volume and length showed superior diagnostic accuracy (PPV 55% and 70%, respectively). CONCLUSION: Measurements of aortic volume and length have superior diagnostic accuracy compared with the maximal diameter and could improve the timely identification of patients at risk for ATAAD.

Clinical assessment of aortic valve stenosis: Comparison between 4D flow MRI and transthoracic echocardiography.

BACKGROUND: The prevalence of valvular aortic stenosis (AS) increases as the population ages. Echocardiographic measurements of peak jet velocity (Vpeak ), mean pressure gradient (Pmean ), and aortic valve area (AVA) determine AS severity and play a pivotal role in the stratification towards valvular replacement. A multimodality imaging approach might be needed in cases of uncertainty about the actual severity of the stenosis. PURPOSE: To compare four-dimensional phase-contrast magnetic resonance (4D PC-MR), two-dimensional (2D) PC-MR, and transthoracic echocardiography (TTE) for quantification of AS. STUDY TYPE: Prospective. POPULATION: Twenty patients with various degrees of AS (69.3 ± 5.0 years). FIELD STRENGTH/SEQUENCES: 4D PC-MR and 2D PC-MR at 3T. ASSESSMENT: We compared Vpeak , Pmean , and AVA between TTE, 4D PC-MR, and 2D PC-MR. Flow eccentricity was quantified by means of normalized flow displacement, and its influence on the accuracy of TTE measurements was investigated. STATISTICAL TESTS: Pearson's correlation, Bland-Altman analysis, paired t-test, and intraclass correlation coefficient. RESULTS: 4D PC-MR measured higher Vpeak (r = 0.95, mean difference + 16.4 ± 10.7%, P <0.001), and Pmean (r = 0.92, mean difference + 14.9 ± 16.0%, P = 0.013), but a less critical AVA (r = 0.80, mean difference + 19.9 ± 20.6%, P = 0.002) than TTE. In contrast, unidirectional 2D PC-MR substantially underestimated AS severity when compared with TTE. Differences in Vpeak between 4D PC-MR and TTE showed to be strongly correlated with the eccentricity of the flow jet (r = 0.89, P <0.001). Use of 4D PC-MR improved the concordance between Vpeak and AVA (from 0.68 to 0.87), and between PGmean and AVA (from 0.68 to 0.86). DATA CONCLUSION: 4D PC-MR improves the concordance between the different AS parameters and could serve as an additional imaging technique next to TTE. Future studies should address the potential value of 4D PC-MR in patients with discordant echocardiographic parameters. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:472-480.

Initial Imaging-Guided Strategy Versus Routine Care in Patients With Non-ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Patients with non-ST-segment elevation myocardial infarction and elevated high-sensitivity cardiac troponin levels often routinely undergo invasive coronary angiography (ICA), but many do not have obstructive coronary artery disease. OBJECTIVES: This study investigated whether cardiovascular magnetic resonance imaging (CMR) or computed tomographic angiography (CTA) may serve as a safe gatekeeper for ICA. METHODS: This randomized controlled trial (NCT01559467) in 207 patients (age 64 years; 62% male patients) with acute chest pain, elevated high-sensitivity cardiac troponin T levels (>14 ng/l), and inconclusive electrocardiogram compared a CMR- or CTA-first strategy with a control strategy of routine clinical care. Follow-up ICA was recommended when initial CMR or CTA suggested myocardial ischemia, infarction, or obstructive coronary artery disease (≥70% stenosis). Primary efficacy and secondary safety endpoints were referral to ICA during hospitalization and 1-year outcomes (major adverse cardiac events and complications), respectively. RESULTS: The CMR- and CTA-first strategies reduced ICA compared with routine clinical care (87% [p = 0.001], 66% [p < 0.001], and 100%, respectively), with similar outcome (hazard ratio: CMR vs. routine, 0.78 [95% confidence interval: 0.37 to 1.61]; CTA vs. routine, 0.66 [95% confidence interval: 0.31 to 1.42]; and CMR vs. CTA, 1.19 [95% confidence interval: 0.53 to 2.66]). Obstructive coronary artery disease after ICA was found in 61% of patients in the routine clinical care arm, in 69% in the CMR-first arm (p = 0.308 vs. routine), and in 85% in the CTA-first arm (p = 0.006 vs. routine). In the non-CMR and non-CTA arms, follow-up CMR and CTA were performed in 67% and 13% of patients and led to a new diagnosis in 33% and 3%, respectively (p < 0.001). CONCLUSIONS: A novel strategy of implementing CMR or CTA first in the diagnostic process in non-ST-segment elevation myocardial infarction is a safe gatekeeper for ICA.

Predictive imaging for thoracic aortic dissection and rupture: moving beyond diameters.

Acute aortic syndromes comprise a group of potentially fatal conditions that result from weakening of the aortic vessel wall. Pre-emptive surgical intervention is currently reserved for patients with severe aortic dilatation, although abundant evidence describes the occurrence of dissection and rupture in aortas with diameters below surgical thresholds. Modern imaging techniques (such as hybrid PET-CT and 4D flow MRI) afford the non-invasive assessment of anatomic, hemodynamic, and molecular features of the aorta, and may provide for a more accurate selection of patients who will benefit from preventative surgical intervention. In the current review, we summarize evidence and considerations regarding predictive aortic imaging and highlight evolving imaging modalities that have shown promise to improve risk assessment for the occurrence of dissection and rupture. KEY POINTS: • Guidelines for the preventative management of aortic disease depend on maximal vessel diameters, while these have shown to be poor predictors for the occurrence of catastrophic acute aortic events. • Evolving imaging modalities (such as 4D flow MRI and hybrid PET-CT) afford a more comprehensive insight into anatomic, hemodynamic, and molecular features of the aorta and have shown promise to detect vessel wall instability at an early stage.

The daily practice of direct oral anticoagulant use in patients with atrial fibrillation; an observational cohort study.

BACKGROUND: Direct oral anticoagulants (DOACs) are administered in fixed doses without monitoring. There is still little published data on the impact of the absence of monitoring on adherence to medication and stability of DOAC plasma levels over time. OBJECTIVES: To explore adherence and stability of DOAC plasma levels over time in patients with atrial fibrillation (NVAF) recently started on DOAC therapy. PATIENTS AND METHODS: A prospective observational cohort study with structured follow up including assessment of adherence to medication, plasma levels at baseline, 3,6 and 12 months and adverse events. RESULTS: We included 164 patients; 89% were previous users of a vitamin K antagonist (VKA). One-year adherence was reasonably good: Morisky adherence measurement scores of 6-8 in 92%. The majority of DOAC plasma levels were within reported on-therapy ranges; dabigatran (median 104.4 ng/ml, IQR 110.2), rivaroxaban (median 185.2 ng/ml, IQR 216.1) and on average levels were not different for full and adjusted doses. There was significant variation between patients, but no significant differences over time within individuals. A substantial proportion of patients starting in the upper-or lower 20th percentiles remained there during the entire follow up. Seventeen bleedings (16 minor, 1 major) were reported, no ischemic events and bleeding or thrombotic events were not associated with DOAC plasma levels. CONCLUSIONS: Adherence was reasonably good in the majority of patients. Our data confirm the stability of DOAC plasma levels over time. Knowledge of such data may, in the individual patient, contribute to optimal drug and dose selection.

Adding Speckle-Tracking Echocardiography to Visual Assessment of Systolic Wall Motion Abnormalities Improves the Detection of Myocardial Infarction.

BACKGROUND: The aim of this study was to investigate whether speckle-tracking echocardiography (STE) improves the detection of myocardial infarction (MI) over visual assessment of systolic wall motion abnormalities (SWMAs) using delayed enhancement cardiac magnetic resonance imaging as a reference. METHODS: Transthoracic echocardiography was performed in 95 patients with first ST segment elevation MI 110 days (interquartile range, 97-171 days) after MI and in 48 healthy control subjects. Two experienced observers independently assessed SWMAs. Separately, longitudinal peak negative, peak systolic, end-systolic, global strain, and strain rate were measured and averaged for the American Heart Association-recommended coronary artery perfusion territories. Receiver operating characteristic analysis was used to determine a single optimal cutoff value for each strain parameter. The diagnostic accuracy of an algorithm combining visual assessment and STE was evaluated. RESULTS: Median infarct size and transmurality were 15% (interquartile range, 7%-24%) and 64% (interquartile range, 46%-78%), respectively. Sensitivity, specificity, and accuracy of visual assessment to detect MI were 74% (95% CI, 63%-82%), 85% (95% CI, 72%-93%), and 78% (95% CI, 70%-84%), respectively. Among the strain parameters, SR had the highest diagnostic accuracy (area under the curve, 0.88; 95% CI, 0.83-0.94; cutoff value, -0.97 sec-1). The combination with STE improved sensitivity compared with visual assessment alone (94%; 95% CI, 86%-97%; P < .001), minimally affecting specificity (79%; 95% CI, 65%-89%; P = .607). Overall accuracy improved to 89% (95% CI, 82%-93%; P = .011). Multivariate analysis accounting for age and sex demonstrated that SR was independently associated with MI (odds ratio, 2.0; 95% CI, 1.6-2.7). CONCLUSIONS: The sensitivity and diagnostic accuracy of visually detecting chronic MI by assessing SWMAs are moderate but substantially improve when adding STE.