Regional differences of fat depot attenuation using non-contrast, contrast-enhanced, and delayed-enhanced cardiac CT.

BACKGROUND: Regional fat density assessed by computed tomography (CT) has been suggested as a marker of perivascular adipose tissue inflammation. Dual energy CT (DECT) allows improved tissue characterization compared to conventional CT. PURPOSE: To explore whether DECT might aid regional fat density discrimination. MATERIAL AND METHODS: We included patients who had completed a non-enhanced cardiac CT scan, CT coronary angiography (CTCA), and a delayed enhancement CT. Attenuation levels (Hounsfield units [HU]) were assessed at the epicardial, paracardial, visceral, and subcutaneous fat. The number of coronary segments with disease (SIS) was calculated. RESULTS: A total of 36 patients were included in the analysis. Twenty-six (72%) patients had evidence of obstructive disease at CCTA and 25 (69%) patients had evidence of previous myocardial infarction. At non-contrast CT, we did not identify significant attenuation differences between epicardial, paracardial, subcutaneous, and visceral fat depots (-110.8 ± 9 HU, vs. -113.7 ± 9 HU, vs. -114.7 ± 8 HU, vs. -113.8 ± 11 HU, P = 0.36). Significant attenuation differences were detected between fat depots at mid and low energy levels, both at CTCA and delayed-enhancement scans ( P < 0.05 for all). Epicardial fat showed the least negative attenuation, irrespective of the acquisition mode; epicardial fat evaluated at 40 keV was related to the SIS (r = 0.37, P = 0.03). CONCLUSIONS: In this study, regional fat depots amenable to examination during thoracic CT scans have distinctive regional attenuation values. Furthermore, such differences were better displayed using contrast-enhanced monochromatic imaging at low energy levels.

Exaggerated Interventricular Dependence Among Patients With Pectus Excavatum: Combined Assessment With Cardiac MRI and Chest CT.

OBJECTIVE: We sought to explore whether patients with pectus excavatum have exaggerated interventricular dependence and to evaluate the impact of the malformation severity (assessed on CT) on both anatomic and functional cardiac parameters (assessed on cardiac MRI). SUBJECTS AND METHODS: The current study involved consecutive patients with a diagnosis of pectus excavatum who were referred to undergo cardiac MRI and chest CT to establish surgical candidacy or to define treatment strategies. RESULTS: Sixty-two patients with pectus excavatum underwent cardiac MRI and chest CT. Fifty (81%) patients were male, and the median age was 17.5 years (range, 14.0-23.0 years). Forty-seven (76%) patients had evidence of right ventricular compression. The left ventricle showed a significantly decreased end-diastolic volume (inspiration vs expiration: 70.4 ± 11.6 vs 76.1 ± 13.7 mL/m2, respectively; p = 0.01) and a significantly higher eccentricity index (1.52 ± 0.2 vs 1.20 ± 0.1, p < 0.0001) during inspiration than during expiration. The median respiratory-related septal excursion was 8.1% (interquartile range, 5.1-11.7%). Patients with pericardial effusion showed a significantly higher pectus excavatum severity index than patients without pericardial effusion (6.3 ± 3.4 vs 4.4 ± 1.3, respectively; p = 0.003). Patients with a relative septal excursion equal to or larger than 11.8% showed a significantly higher pectus excavatum severity index than patients with a relative septal excursion of less than 11.8% (6.3 ± 2.6 vs 4.7 ± 2.4, respectively; p = 0.05). CONCLUSION: In this study, patients with pectus excavatum showed significant alterations of cardiac morphology and function that were related to the deformation severity and that manifest as an exaggerated interventricular dependence.

Detection of Myocardial Infarction Using Delayed Enhancement Dual-Energy CT in Stable Patients.

OBJECTIVE: The objective of our study was to explore whether delayed enhancement dual-energy CT (DECT) allows the detection of myocardial infarcts in stable patients. SUBJECTS AND METHODS: Patients with known or suspected coronary artery disease clinically referred for myocardial perfusion imaging using SPECT were prospectively included. All patients (n = 34) also underwent stress, rest, and delayed enhancement DECT on a DECT scanner. At SPECT, segments with myocardial infarction (MI) were defined as those with a summed rest score of ≥ 2 in two or more consecutive segments, and a diagnosis of MI was supported by wall motion abnormalities, clinical history, and ECG findings. RESULTS: Segments with MI were identified in 13 (38%), 15 (44%), and 14 (41%) patients using SPECT, perfusion CT, and delayed enhancement DECT, respectively. When combined SPECT and perfusion CT results were used as the reference standard, delayed enhancement DECT had a sensitivity, specificity, positive predictive value, and negative predictive value for the detection of MI of 91.7% (95% CI, 62-98%), 86.4% (95% CI, 65-97%), 78.6% (95% CI, 49-95%), and 95.0% (95% CI, 75-100%). At delayed enhancement DECT (40 keV), a signal attenuation higher than 161 HU had a sensitivity of 72% and a specificity of 79% for the detection of MI on a per-segment basis. The median signal attenuation of myocardial infarcts at 40 keV was 3.0 SDs (interquartile range, 1.3-4.0 SDs) above that of normal myocardium. CONCLUSION: In this study, delayed enhancement DECT allowed the detection of myocardial infarcts in stable patients.

Improved Discrimination of Myocardial Perfusion Defects at Low Energy Levels Using Virtual Monochromatic Imaging.

OBJECTIVES: The aim of this study was to explore the diagnostic performance of dual-energy computed tomography perfusion (DE-CTP) at different energy levels. METHODS: Patients with known or suspected coronary artery disease underwent stress and rest DE-CTP and single-photon emission computed tomography. Images were evaluated using monochromatic data, and perfusion defects were initially identified in a qualitative manner and subsequently confirmed using attenuation levels. RESULTS: Thirty-six patients were included. Sensitivity, specificity, positive predictive value, and negative predictive value of DE-CTP for the identification of perfusion defects were 84.1%, 94.2%, 77.3%, and 96.2%, respectively. Perfusion defects showed significantly lower attenuation than normal segments, with the largest differences among low energy levels (sensitivity of 96% and specificity of 98% using a cutoff value ≤ 153 Hounsfield units at 40 keV), progressively declining at the higher levels (P < 0.001). CONCLUSIONS: Dual-energy CTP at the lowest energy levels allowed improved discrimination of perfusion defects compared with higher energy levels.

Sternal torsion in pectus excavatum is related to cardiac compression and chest malformation indexes.

BACKGROUND/PURPOSE: The role of sternal torsion (ST) in patients with pectus excavatum (PEX) is unknown. We evaluated the relationship between ST and both chest malformation and cardiac compression (CC) indexes. METHODS: We included consecutive patients with PEX who underwent chest computed tomography and cardiac magnetic resonance (CMR) to define surgical candidacy. Malformation indexes included the Haller index (HI), correction index (CI), and ST. CC and the tricuspid to mitral annulus width ratio were evaluated using CMR. RESULTS: One-hundred and sixteen patients were included, with a mean HI of 5.8 ±â€¯3.6 and a mean CI of 35.8 ±â€¯18.0%. ST was significantly related to malformation indexes, being patients with absence of ST those showing the lowest HI (p = 0.048) and CI (p = 0.002). Right-sided ST was significantly related to the CC classification (p = 0.0001), and the tricuspid/mitral annulus width ratio was significantly lower among these patients (absence 0.98 ±â€¯0.15, left-sided 0.91 ±â€¯0.10, right-sided 0.80 ±â€¯0.15, p < 0.0001). A significant inverse relationship between ST degrees and the tricuspid/mitral ratio was also identified (r = -0.47, p < 0.0001). CONCLUSIONS: We identified a significant relationship between ST and both chest malformation and CC indexes; the absence of ST being identified as a marker of an overall more benign phenotype. TYPE OF STUDY: Study of diagnostic test. LEVEL OF EVIDENCE: Level II.

[Myocardial ischemia without coronary obstructions: MINOCA-INOCA. Review for decision making]. / Isquemia miocárdica sin lesiones coronarias obstructivas: MINOCA-INOCA. Revisión para la toma de decisiones.

One in every four coronarographies performed to study myocardial ischemia shows coronary angiographic stenosis less than 50%. This data triggered an increasing interest in the medical community. The American Society of Cardiology recently published a position paper about the pathophysiology, diagnosis and treatment of this entity. Our group performed a narrative review reflecting the opinion of cardiology experts from different centers in Argentina. It aims physiopatologic and diagnostic aspect to understand the current approach in patients with MINOCA (myocardial infarction with non-obstructive coronary arteries) e INOCA (demonstrated angina and ischemia but without coronary lesions that justify this syndrome).

Una de cada 4 coronariografías realizadas por isquemia miocárdica presenta lesiones menores al 50% Este dato desencadenó un creciente interés en la comunidad médica. La Sociedad Americana de Cardiología publicó recientemente un artículo que describe la posición consensuada de un grupo de expertos sobre la fisiopatología, el diagnóstico y el tratamiento de esta entidad. Nuestro trabajo refleja una revisión narrativa y la posición de un grupo de expertos pertenecientes a diferentes instituciones con servicios de Cardiología jerarquizados. Aborda aspectos fisiopatológicos y diagnósticos para comprender el enfoque actual del tratamiento, tanto en pacientes que ingresan con diagnóstico de MINOCA (infa rto de miocardio con lesiones angiográficas no graves) o de INOCA (angina e isquemia demostradas, pero sin lesiones coronarias que justifiquen este síndrome).

Impact of pectus excavatum on cardiac morphology and function according to the site of maximum compression: effect of physical exertion and respiratory cycle.

AIMS: Previous studies have demonstrated diverse cardiac manifestations in patients with pectus excavatum (PEX), although mostly addressing morphological or physiological impact as separate findings. Using multimodality imaging, we evaluated the impact of PEX on cardiac morphology and function according to the site of maximum compression, and the effect of exertion and breathing. METHODS AND RESULTS: All patients underwent chest computed tomography, cardiac magnetic resonance (CMR), and stress echocardiography (echo) in order to establish surgical candidacy. We evaluated diastolic function and trans-tricuspid gradient during stress (echo); and systolic function and respiratory-related septal wall motion abnormalities (CMR). Patients were classified according to the site of cardiac compression as type 0 (without cardiac compression); type 1 (right ventricle); and type 2 [right ventricle and atrioventricular (AV) groove]. Fifty-nine patients underwent multimodality imaging, with a mean age of 19.5 ± 5.9 years. Compared with a sex and age matched control group, peak exercise capacity was lower in patients with PEX (8.4 ± 2.0 METs vs. 15.1 ± 4.6 METs, P < 0.0001). At stress, significant differences were found between groups regarding left ventricular E/A (P = 0.004) and e/a ratio (P = 0.005), right ventricular E/A ratio (P = 0.03), and trans-tricuspid gradient (P = 0.001). At CMR, only 9 (15%) patients with PEX had normal septal motion, whereas 17 (29%) had septal flattening during inspiration. Septal motion abnormalities were significantly related to the cardiac compression classification (P < 0.0001). CONCLUSIONS: The present study demonstrated that patients with PEX, particularly those with compression affecting the right ventricle and AV groove, manifest diverse cardiac abnormalities that are mostly related to exertion, inspiration, and diastolic function.

Relationship between left atrial dimensions and global and regional fat depots.

Background and Objectives: The relationship between body fat depots and the left atrial (LA) dimensions has not been fully explored. Our objective is to determine if there is a relationship not only with total body fat depots, but specifically with regional fatty depots. Materials and Methods: It was an observational, retrospective study that included consecutive patients referred to our institution with an order to perform computed tomography angiography triggered by electrocardiogram for different clinical indications. Measurements of the LA were made in the systolic phase, using four and two cameras views. Results: A total of 87 patients were included. The mean age was 66.4 ± 12.5 years; 67% were men. The LA volume indexed by the body surface area was 48.0 ± 16.6 cm3/m2. We identified significant correlations between the LA dimensions and the age (p < 0.05). However, no significant correlations were found between the LA dimensions and the body fat depots, either total or regional. Conclusions: In this study, we did not identify significant relationships between LA dimensions and global or regional body fat depots.

Antecedentes y objetivos: La relación entre los depósitos de grasa corporal y las dimensiones de la aurícula izquierda (AI) no ha sido del todo explorada. Nuestro objetivo es determinar si existe relación no solo con los depósitos de grasa corporal totales, sino específicamente con los depósitos grasos regionales. Materiales y métodos: Estudio observacional, retrospectivo, que incluyó pacientes consecutivos remitidos a nuestra institución con orden de realización de angiotomografía computarizada toracoabdominal gatillada con electrocardiograma por distintas indicaciones clínicas. Las mediciones de la AI se realizaron en la fase sistólica, utilizando vistas de cuatro y dos cámaras. Resultados: Se incluyeron un total de 87 pacientes. La edad media fue de 66.4 ± 12.5 años; un 67% de los sujetos fueron hombres. El volumen de la AI indexado por la superficie corporal fue de 48.0 ± 16.6 cm3/m2. Identificamos correlaciones significativas entre las dimensiones de la AI y la edad (p < 0.05). Sin embargo, no se evidenciaron correlaciones significativas entre las dimensiones de la AI y los distintos depósitos de grasa corporal, ya sea totales o regionales. Conclusiones: En este estudio, no identificamos relaciones significativas entre las dimensiones de la AI y los depósitos de grasa corporal globales o regionales.

Evaluation of pectus excavatum indexes during standard cardiac magnetic resonance: Potential for single preoperative tool.

PURPOSE: Preoperative assessment of patients with pectus excavatum (PE) demands evaluation of malformation indexes, generally with chest computed tomography (CT). In addition, assessment of the cardiac impact of sternal depression has become a rule in high referral centers, thus requiring two independent imaging modalities and use ionizing radiation in a very young population. The objective of this study was to explore the agreement between chest CT and standard cardiac MR (CMR) for the evaluation of chest wall malformation indexes. METHODS: We included consecutive patients with PE referred to undergo chest CT and CMR to establish surgical candidacy and/or to define treatment strategies. Both CT and CMR were performed at full-expiration. In both modalities, the Haller index (HI) and the Correction index (CI) were calculated by two independent observers. In CMR, only scout images were used. Agreement was evaluated using intra-class correlation coefficients (ICC). RESULTS: Fifty patients comprised the study population (median age 19.0 years) and underwent chest CT and CMR within the same month. CMR assessment of chest malformation indexes was reproducible, with a very good inter-observer agreement for HI [ICC 0.93 (0.88-0.96), p < 0.0001] and CI [ICC 0.91 (0.83-0.95), p < 0.0001]. CMR also had a very good agreement with chest CT for HI [ICC 0.90 (0.82-0.94), p < 0.0001] and CI measurements [ICC 0.93 (95% CI 0.88-0.96), p < 0.0001]. CONCLUSIONS: We demonstrated an excellent agreement between chest CT and standard CMR for the assessment of chest wall malformations, thus potentially enabling preoperative assessment of PE severity and cardiac involvement with a single diagnostic tool.

Role of Iterative Reconstruction Algorithm for the Assessment of Myocardial Infarction with Dual Energy Computed Tomography.

RATIONALE AND OBJECTIVES: Low monochromatic energy levels (40 keV) derived from delayed enhancement dual energy cardiac computed tomography (DE-DECT) allow the evaluation of myocardial infarcts (MI) among stable patients, although at the expense of high image noise. We explored whether the application of adaptive statistical iterative reconstruction (ASIR) to 40-keV DE-DECT (unavailable with previous software versions) might improve image quality and detection of MI in stable patients. MATERIALS AND METHODS: We prospectively enrolled patients with a history of previous MI, and performed delayed-enhancement cardiac magnetic resonance (DE-CMR) and DE-DECT within the same week. DE-DECT images were reconstructed with 0% and 60% ASIR. RESULTS: MI was identified in 18 (80%) patients with both DE-CMR and DE-DECT. On a per segment basis, we did not identify significant differences regarding the diagnostic performance of DE-DECT with and without ASIR [area under receiver operating characteristic curve 0.86 vs. 0.83, p = 0.10]. The application of ASIR improved the signal-to-noise ratio of DE-DECT with 0% ASIR compared to DE-DECT with 60% ASIR (6.07 ± 2.1 vs. 11.1 ± 4.5, p < 0.0001). However, qualitative assessment of MI image quality (3.35 ± 1.2, vs. 3.55 ± 1.1, p = 0.10) and diagnostic confidence (4.40 ± 0.9 vs. 4.60 ± 0.8, p = 0.10) were not significantly improved. Using DE-DECT with 60% ASIR, a threshold over 199 HU showed a sensitivity of 67% and a specificity of 92% for the detection of segments with MI. CONCLUSION: In this study, DE-DECT allowed accurate detection of MI among stable patients compared with DE-CMR, and the application of ASIR improved signal-to-noise ratio of DE-DECT, although the diagnostic performance showed only non-significant improvements.

Relationship between left atrial dimensions and global and regional fat depots.

Background and Objectives: The relationship between body fat depots and the left atrial (LA) dimensions has not been fully explored. Our objective is to determine if there is a relationship not only with total body fat depots, but specifically with regional fatty depots. Materials and Methods: It was an observational, retrospective study that included consecutive patients referred to our institution with an order to perform computed tomography angiography triggered by electrocardiogram for different clinical indications. Measurements of the LA were made in the systolic phase, using four and two cameras views. Results: A total of 87 patients were included. The mean age was 66.4 ± 12.5 years; 67% were men. The LA volume indexed by the body surface area was 48.0 ± 16.6 cm3/m2. We identified significant correlations between the LA dimensions and the age (p < 0.05). However, no significant correlations were found between the LA dimensions and the body fat depots, either total or regional. Conclusions: In this study, we did not identify significant relationships between LA dimensions and global or regional body fat depots.

Antecedentes y objetivos: La relación entre los depósitos de grasa corporal y las dimensiones de la aurícula izquierda (AI) no ha sido del todo explorada. Nuestro objetivo es determinar si existe relación no solo con los depósitos de grasa corporal totales, sino específicamente con los depósitos grasos regionales. Materiales y métodos: Estudio observacional, retrospectivo, que incluyó pacientes consecutivos remitidos a nuestra institución con orden de realización de angiotomografía computarizada toracoabdominal gatillada con electrocardiograma por distintas indicaciones clínicas. Las mediciones de la AI se realizaron en la fase sistólica, utilizando vistas de cuatro y dos cámaras. Resultados: Se incluyeron un total de 87 pacientes. La edad media fue de 66.4 ± 12.5 años; un 67% de los sujetos fueron hombres. El volumen de la AI indexado por la superficie corporal fue de 48.0 ± 16.6 cm3/m2. Identificamos correlaciones significativas entre las dimensiones de la AI y la edad (p < 0.05). Sin embargo, no se evidenciaron correlaciones significativas entre las dimensiones de la AI y los distintos depósitos de grasa corporal, ya sea totales o regionales. Conclusiones: En este estudio, no identificamos relaciones significativas entre las dimensiones de la AI y los depósitos de grasa corporal globales o regionales.

Preoperative multimodality imaging of pectus excavatum: State of the art review and call for standardization.

PURPOSE: Image acquisition protocols and reports in patients with pectus excavatum (PEX) differ significantly from routine examinations, and no imaging modality can enable a comprehensive assessment of PEX severity and cardiac impact within a single examination. We therefore attempt to establish recommendations about preoperative imaging in patients with PEX. METHOD: Chest computed tomography (CT), stress echocardiography (Echo), and cardiac magnetic resonance (CMR) allow the evaluation of specific information regarding structural and functional characteristics of vital importance to assess surgical candidacy and define surgical strategies. We sought to provide a multidisciplinary state of the art document involving thoracic surgeons, radiologists, and cardiologists; to establish recommendations about the variables to be included in the reports of the imaging examinations performed in patients with PEX. RESULTS: We provide recommendations for preoperative image acquisition and analysis, aimed at the assessment of the severity of the chest wall deformity (CT); the site of maximum cardiac compression, extent of increased interventricular dependence, and presence of pericardial effusion (CMR); and the effect of PEX on the functional capacity and exercise-related systolic and/or diastolic function, and tricuspid annulus compression (Echo). CONCLUSIONS: This multidisciplinary state of the art document involving thoracic surgeons, radiologists, and cardiologists provides recommendations about preoperative imaging for patients with PEX.

Relationship between cardiac MR compression classification and CT chest wall indexes in patients with pectus excavatum.

BACKGROUND/PURPOSE: In pectus excavatum (PE) patients owing to the location of the heart in the chest cavity, the most affected site of compression by the depressed chest wall is the right heart, and surgical repair has shown to provide a significant relief in the RH cavities compression. Our aim was to explore the relationship between the site of right cardiac compression, chest wall indexes (CT-CWI) and the sternal torsion angle (STA) based on cardiac magnetic resonance (CMR) and computed tomography (CT) among PE patients. METHODS: We included PE patients with no previous surgical correction referred to CMR and chest CT imaging as presurgical evaluations. The following CT-CWI were calculated: Haller Index (HI), correction index (CI) and STA. A CMR compression classification (CMR-CC) was implemented based on the analysis (in the horizontal long axis plane at end of diastole) of the right cardiac compression site, caused by the thoracic cage (sternum/ribs): Type 0 (T0): absence of cardiac compression; Type 1 (T1): compression of the lateral wall of the right ventricle (RV) without involvement of the atrioventricular (AV) groove; Type 2 (T2): compression of the RV involving the AV groove. RESULTS: Sixty PE patients underwent CMR and chest CT. Fifty (81%) patients were male, and the median age was 17.5 (14.0; 23.0) years. T0, T1 and T2 were found in 14 (23%), 27 (45%) and 19 (32%) patients. There were significant differences between types with regard to the HI (T0 3.9 ±â€¯1.1, T1 4.8 ±â€¯2.0, T2 6.4 ±â€¯3.1, p < 0.009) and to the CI (T0 22.1 ±â€¯10.4%, T1 31.6 ±â€¯16.1%, T2 46.9 ±â€¯16.3% p < 0.0001) and STA (T0 9.1 ±â€¯7.9°, T1 12.7 ±â€¯10.3°, class T2 23.0 ±â€¯13.6°p = 0.001) respectively. CONCLUSION: In this study, we established a cardiac magnetic resonance compression classification of patients with pectus excavatum comprising a simple discrimination of cardiac compression sites, which were related to chest wall indexes. TYPE OF STUDY: Study of Diagnostic Test. LEVEL OF EVIDENCE: Level II.

Dual energy cardiac CT.

Conventional single energy CT suffers from technical limitations related to the polychromatic nature of X-rays. Dual energy cardiac CT (DECT) shows promise to attenuate and even overcome some of these limitations, and might broaden the scope of patients eligible for cardiac CT towards the inclusion of higher risk patients. This might be achieved as a result of both safety (contrast reduction) and physiopathological (myocardial perfusion and characterization) issues. In this article, we will review the main clinical cardiac applications of DECT, that can be summarized in two core aspects: coronary artery evaluation, and myocardial evaluation.

Pericardial fat volume is related to atherosclerotic plaque burden rather than to lesion severity.

AIMS: We sought to explore the relationship between pericardial fat volume (PFV) and both coronary atherosclerosis (CA) extent and severity using coronary artery calcium score (CAC), computed tomography coronary angiography (CTCA), and invasive coronary angiography in patients at high to intermediate likelihood of coronary artery disease (CAD). METHODS AND RESULTS: Patients clinically referred to invasive angiography who underwent CTCA and CAC within 1 month before the procedure comprised the study population. PFV, CAC, atherosclerotic burden indexes [segment involvement score (SIS); segment stenosis score; three-vessel plaque; and any left main plaque], and the invasive angiography-derived CAD index were evaluated independently. A total of 75 patients were included in the study. PFV did not differ between patients with or without obstructive (stenosis >70%) CAD defined by invasive angiography (86.4 ± 31.7 vs. 77.1 ± 42.8 cm3, P = 0.34), although patients with obstructive CAD had significantly higher CAC scores [636.0 (IQR 229.5-1101.0) vs. 206.0 (IQR 0.0-675), P < 0.0001] than patients without obstructive CAD. Patients with extensive CA (SIS > 5) had significantly larger PFV (89.9 ± 33.9 vs. 58.7 ± 33.2 cm3, P = 0.003) than patients with non-extensive CA. Significant correlations were found between PFV and CAC (r = 0.49, P < 0.0001), and SIS (r = 0.46, P < 0.0001), whereas very weak correlations were observed between PFV and the CAD index (r = 0.27, P = 0.02), and between PFV and the body mass index (r = 0.33, P = 0.004). CONCLUSION: The main finding of the present study was the identification of PFV as more closely related to atherosclerotic plaque burden rather than to lesion severity in patients referred to invasive coronary angiography.

Spectral Signal Density of Carotid Plaque Using Dual-Energy Computed Tomography.

BACKGROUND AND PURPOSE: Plaque characterization using virtual monochromatic imaging derived from dual-energy computed tomography (CT) angiography requires the determination of normal signal density values of each plaque component. We sought to explore the signal density values of carotid plaque components using dual-energy compared to conventional single-energy CT angiography (CTA), and to establish the energy level with the largest differences between plaque components. METHODS: The present prospective study involved consecutive patients referred for carotid artery evaluation by CTA. Two scans (single-energy and dual-energy CTA) were performed in all patients, and a single radiologist analyzed the data. Single-source dual-energy CTA allowed the generation of virtual monochromatic images from 40 to 140 keV. RESULTS: A total of 35 internal carotid artery lesions were examined in 20 symptomatic patients. The mean age was 72.3 ± 6.7 years, and 9 (45%) patients were male. Internal carotid artery geometrical variables including lumen area (P = .96), vessel area (P = .97), and percent area stenosis (P = .99) did not differ between groups (single-energy CTA, and dual-energy CTA at 40, 70, 100, and 140 keV). Differences between signal densities of different tissues were largest at 40 keV (calcium/lumen, P < .0001; fat/noncalcified, P < .0001). CONCLUSIONS: In the present pilot investigation, virtual monochromatic imaging at low-energy levels derived from dual-energy CTA allowed the largest differences in attenuation levels between tissues, without affecting vessel or plaque geometry.

Electrocardiogramas durante el tercer trimestre de embarazo: / Electrocardiography During the Third Trimester of Pregnancy:

RESUMEN Objetivo: Analizar las características electrocardiográficas en embarazadas sin patología cardiovascular. Material y métodos: Estudio de corte transversal, descriptivo, multicéntrico. Se incluyeron pacientes sin patología cardiovascular que cursaban el tercer trimestre de embarazo y que concurrieron a una evaluación cardiológica preparto entre abril y julio de 2020; todas ellas firmaron el consentimiento correspondiente. Resultados: Se analizaron 80 trazados. La mediana de la frecuencia cardíaca fue 82 lpm (RIC: 70-93 lpm). La mediana del eje QRS fue 54° (RIC: 39°-71°). Ondas q e infradesnivel del segmento ST en cara inferior y de V4 a V6 fueron hallazgos relativamente frecuentes. La mediana del QTc fue 422 mseg (RIC: 404 mseg-445 mseg). La mediana del tiempo del pico de la onda T a su fin fue 86 mseg (RIC: 74-95 mseg). Conclusión: Las alteraciones más frecuentes ocurrieron en DIII, DII, aVf y de V4 a V6. Las ondas q y el infraST fueron los cambios principales. Fueron infrecuentes las desviaciones del eje, la taquicardia sinusal o el QTc prolongado.

ABSTRACT Objective: The aim of this study was to analyze the electrocardiographic characteristics in pregnant women without cardiovascular disease. Methods: This was a descriptive, cross-sectional, multicenter study, including patients without cardiovascular disease in their third trimester of pregnancy, who underwent cardiac evaluation before delivery between April and July 2020. All patients signed the corresponding informed consent. Results: A total of 80 tracings were analyzed. Median heart rate was 82 bpm (IQR 70-93 bpm) and median QRS axis was 54° (IQR 39°-71°). Q waves and ST segment depression were relatively frequent in inferior leads and from V4 to V6. Median QTc was 422 msec (IQR 404-445 msec) and median time from T wave peak to T wave end was 86 msec (IQR 74-95 msec). Conclusion: The most common changes occurred in T wave peak to T wave end and from V4 to V6. Main changes included q waves and ST-segment depression. Axis deviations, sinus tachycardia or prolonged QTc were rare.

Reproducibility of Gadolinium Enhancement Patterns and Wall Thickness in Hypertrophic Cardiomyopathy.

BACKGROUND: Reproducibility data of the extent and patterns of late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM) is limited. OBJECTIVE: To explore the reproducibility of regional wall thickness (WT), LGE extent, and LGE patterns in patients with HCM assessed with cardiac magnetic resonance (CMR). METHODS: The extent of LGE was assessed by the number of segments with LGE, and by the total LV mass with LGE (% LGE); and the pattern of LGE-CMR was defined for each segment. RESULTS: A total of 42 patients (672 segments) with HCM constituted the study population. The mean WT measurements showed a mean difference between observers of -0.62 ± 1.0 mm (6.1%), with limits of agreement of 1.36 mm; -2.60 mm and intraclass correlation coefficient (ICC) of 0.95 (95% CI 0.93-0.96). Maximum WT measurements showed a mean difference between observers of -0.19 ± 0.8 mm (0.9%), with limits of agreement of 1.32 mm; -1.70 mm, and an ICC of 0.95 (95% CI 0.91-0.98). The % LGE showed a mean difference between observers of -1.17 ± 1.2 % (21%), with limits of agreement of 1.16%; -3.49%, and an ICC of 0.94 (95% CI 0.88-0.97). The mean difference between observers regarding the number of segments with LGE was -0.40 ± 0.45 segments (11%), with limits of agreement of 0.50 segments; -1.31 segments, and an ICC of 0.97 (95% CI 0.94-0.99). CONCLUSIONS: The number of segments with LGE might be more reproducible than the percent of the LV mass with LGE.

Extension and Spatial Distribution of Atherosclerotic Burden Using Virtual Monochromatic Imaging Derived From Dual-energy Computed Tomography.

INTRODUCTION AND OBJECTIVES: We explored the differences between atherosclerotic burden with invasive coronary angiography and virtual monochromatic imaging derived from dual-energy computed tomography coronary angiography. METHODS: Eighty consecutive patients referred for invasive coronary angiography underwent dual-energy computed tomography coronary angiography and were categorized according to the atherosclerotic burden extent using the modified Duke prognostic coronary artery disease index, coronary artery disease extension score, segment involvement score, and the segment stenosis score. RESULTS: The mean segment involvement score (8.2 ± 3.9 vs 6.0 ± 3.7; P < .0001), modified Duke index (4.33 ± 1.6 vs 4.0 ± 1.7; P = .003), coronary artery disease extension score (4.84 ± 1.8 vs 4.43 ± 2.1; P = .005), and the median segment stenosis score (13.5 [9.0-18.0] vs 9.5 [5.0-15.0]; P < .0001) were significantly higher on dual-energy computed tomography compared with invasive angiography. Dual-energy computed tomography showed a significantly higher number of patients with any left main coronary artery lesion (46 [58%] vs 18 [23%]; P < .0001) and with severe proximal lesions (0.28 ± 0.03 vs 0.26 ± 0.03; P < .0001) than invasive angiography. Levels of coronary artery calcification below and above the median showed a sensitivity, specificity, positive predictive value, and negative predictive value of 100% and 97%; 86% and 50%; 93% and 95%; 100% and 67% for the identification of ≥ 50% stenosis. CONCLUSIONS: Dual-energy computed tomography coronary angiography identified a significantly larger atherosclerotic burden compared with invasive coronary angiography, particularly involving the proximal segments.

[Myocardial regional thickness in patients with and without cardiomyopathy assessed by cardiac magnetic resonance]. / Espesores parietales regionales en pacientes con y sin miocardiopatías evaluados por resonancia magnética cardíaca.

OBJECTIVE: To explore regional differences in myocardial wall thickness (WT) among the most prevalent cardiomyopathies and in individuals without structural heart disease using cardiac magnetic resonance. METHODS: Patients older than 18 years referred to cardiac magnetic resonance during the period between January 2014 and September 2014, with a diagnosis of hypertrophic cardiomyopathy, idiopathic dilated cardiomyopathy, ischemic cardiomyopathy, and myocarditis were retrospectively selected from our database. RESULTS: One hundred twenty patients patients were included. The control group had an average WT of 5.9±1.1mm, with a WT index of 2.9±0.8. Significantly lower mean WT in the apical segments were identified in both the control group (basal 6.7±1.3 vs. mid 6.0±1.3 vs. apical 4.6±1.0mm, P<.0001) and in all evaluated cardiomyopathies (hypertrophic cardiomyopathy: basal 10.5±2.4 vs. mid 10.8±2.7 vs. apical 7.3±3.3mm, P<.0001; idiopathic dilated cardiomyopathy: basal 7.7±1.7 vs. mid 7.6±1.3 vs. apical 5.4±1.3mm, P<.0001; ischemic cardiomyopathy: basal 7.4±1.7 vs. mid 7.5±1.9 vs. apical 5.5±1.8mm, P<.0001; myocarditis: basal 7.1±1.5 vs. mid 6.4±1.1 vs. apical 5.1±0.8, P<.0001). Significant gender differences were also evident regarding the mean WT both in the control group (male 6.5±2.1 vs. female 5.2±1.7mm, P<.0001), as in hypertrophic cardiomyopathy (10.5±5.3 vs. 8.5±5.7mm, P<.0001) and myocarditis (6.6±2.0 vs. 5.2±1.6mm, P<.0001). CONCLUSION: We found a relatively high prevalence of segments commonly deemed thinned among patients without structural heart disease. We also observed a marked asymmetry and longitudinal gradient in wall thickness both in controls and in the various cardiomyopathies evaluated.