Evaluation of the Pulmonary Arteries on CTPA With Dual Energy CT: Objective Analysis and Subjective Preferences in a Multireader Study.

PURPOSE: To perform qualitative and quantitative evaluation of low-monoenergetic images (50 KeV) compared with conventional images (120 kVp) in pulmonary embolism (PE) studies and to determine the extent and clinical relevance of these differences as well as radiologists' preferences. MATERIALS AND METHODS: One hundred fifty CT examinations for PE detection conducted on a single-source dual-energy CT were retrospectively evaluated. Attenuation, contrast-to-noise-ratio, and signal-to-noise-ratio were obtained in a total of 8 individual pulmonary arteries on each exam-including both central (450/1200=37.5%) and peripheral (750/1200=62.5%) locations. Results were compared between the conventional and low-monoenergetic images. For quality assessment, 41 images containing PE were presented side-by-side as pairs of slices in both conventional and monoenergetic modes and evaluated for ease in embolus detection by 9 radiologists: cardiothoracic specialists (3), noncardiothoracic specialists (3), and residents (3). Paired samples t tests, a-parametric Wilcoxon test, McNemar test, and kappa statistics were performed. RESULTS: Monoenergetic images had an overall statistically significant increased average ratio of 2.09 to 2.26 (P<0.05) for each measured vessel attenuation, with an increase in signal-to-noise ratio (23.82±9.29 vs. 11.39±3.2) and contrast-to-noise ratio (17.17±6.7 vs 7.27±2.52) (P<0.05). Moreover, 10/150 (6%) of central pulmonary artery measurements considered suboptimal on conventional mode were considered diagnostic on the monoenergetic images (181±14.6 vs. 387.7±72.4 HU respectively, P<0.05). In the subjective evaluation, noncardiothoracic radiologists showed a preference towards low-monoenergetic images, whereas cardiothoracic radiologists did not (74.4% vs. 57.7%, respectively, P<0.05). CONCLUSIONS: The SNR and CNR increase on monoenergetic images may have clinical significance particularly in the setting of sub-optimal PE studies. Noncardiothoracic radiologists and residents prefer low monoenergetic images.

Endomyocardial biopsy in clinical practice: the diagnostic yield and insights from a 5-year single-center experience.

OBJECTIVES: Endomyocardial biopsy (EMB) is a diagnostic tool for evaluating various cardiac conditions, such as myocarditis and myocardial infiltrative diseases. It is also the gold standard screening technique for detecting allograft rejection after heart transplantation. Despite advances in noninvasive imaging modalities for myocardial tissue characterization, EMB is still necessary for making a definitive diagnosis and determining treatment for certain conditions. Herein, we report our recent experience using EMB and its diagnostic yield. METHODS AND RESULTS: We retrospectively reviewed EMBs performed at our institution from March 2018 through March 2023. Clinical data, including patient characteristics, indication and diagnostic yield of EMB, and procedure-related complications, were collected. Histopathological findings of the biopsies were recorded and classified based on the degree to which they matched the clinical diagnosis and cardiac magnetic resonance imaging (CMR) findings. A total of 212 EMBs obtained in 178 consecutive patients were retrospectively analyzed, with 42 biopsies performed for allograft rejection surveillance (10 patients) and the remaining performed for presumptive diagnosis of acute myocarditis or unexplained cardiomyopathy. Among the non-heart transplant cases, 54.7% of EMBs provided a clear diagnosis. The most common diagnosis was myocarditis (69%), followed by cardiac amyloidosis (CA) (26%). EMB was also helpful in detecting several rare cardiac conditions, such as eosinophilic granulomatosis with polyangiitis (EGPA), Fabry disease, and cardiac sarcoidosis. In a cohort of 101 patients who underwent both CMR and EMB, the results were concordant in 66% of cases. However, in 24.7% of patients, EMB was able to identify pathological conditions where CMR results were inconclusive, highlighting its complementary role in determining an accurate diagnosis. No complications were reported in any of the 212 EMBs performed. CONCLUSIONS: With advances in cardiac imaging modalities, EMB is not routinely indicated for the diagnosis of cardiomyopathy. However, EMB is still an important tool for diagnosing specific cardiac diseases and could be crucial for confirming the diagnosis. EMB is generally safe if performed at experienced centers.

Does clinical decision support system promote expert consensus for appropriate imaging referrals? Chest-abdominal-pelvis CT as a case study.

OBJECTIVES: We assessed the appropriateness of chest-abdominal-pelvis (CAP) CT scan use in the Emergency Department (ED), based on expert physicians and the ESR iGuide, a clinical decision support system (CDSS). METHODS: A retrospective cross-study was conducted. We included 100 cases of CAP-CT scans ordered at the ED. Four experts rated the appropriateness of the cases on a 7-point scale, before and after using the decision support tool. RESULTS: Before using the ESR iGuide the overall mean rating of the experts was 5.2 ± 1.066, and it increased slightly after using the system (5.85 ± 0.911 (p < 0.01)). Using a threshold of 5 (on a 7-level scale), the experts considered only 63% of the tests appropriate before using the ESR iGuide. The number increased to 89% after consultation with the system. The degree of overall agreement among the experts was 0.388 before ESR iGuide consultation and 0.572 after consultation. According to the ESR iGuide, for 85% of the cases, CAP CT was not a recommended option (score 0). Abdominal-Pelvis CT was "usually appropriate" for 65 out of the 85 (76%) cases (score 7-9). 9% of the cases did not require CT as first exam modality. CONCLUSIONS: According to both the experts and the ESR iGuide, inappropriate testing was prevalent, in terms of both frequency of the scans and also inappropriately chosen body regions. These findings raise the need for unified workflows that might be achieved using a CDSS. Further studies are needed to investigate the CDSS contribution to the informed decision-making and increased uniformity among different expert physicians when ordering the appropriate test.

Giant Intracardiac Lipoma: A Case Report and the Role of Multimodality Cardiac Imaging.

Cardiac lipomas, especially ones originating from the left ventricle, are extremely rare. They may be asymptomatic or may present with various non-specific symptoms. Herein, we report a case of a giant lipoma of the left ventricle, with frequent ventricular premature beats on electrocardiogram. An echocardiogram demonstrated a large hyperechoic mass occupying a significant portion of the left ventricle. We further describe the diagnostic workup utilizing multimodality cardiac imaging and treatment options. Cardiac MRI demonstrated fat suppression, and cardiac CT showed a homogenous low-attenuation mass suggesting lipomatous matter. The mass was subsequently surgically removed for pathology examination in order to rule out liposarcoma. Histopathology demonstrated mature adipocytes, entrapped myocytes with hypertrophy, and interstitial fibrosis foci confirming the diagnosis of lipoma.

Myocarditis after BNT162b2 mRNA Vaccine against Covid-19 in Israel.

BACKGROUND: Approximately 5.1 million Israelis had been fully immunized against coronavirus disease 2019 (Covid-19) after receiving two doses of the BNT162b2 messenger RNA vaccine (Pfizer-BioNTech) by May 31, 2021. After early reports of myocarditis during adverse events monitoring, the Israeli Ministry of Health initiated active surveillance. METHODS: We retrospectively reviewed data obtained from December 20, 2020, to May 31, 2021, regarding all cases of myocarditis and categorized the information using the Brighton Collaboration definition. We analyzed the occurrence of myocarditis by computing the risk difference for the comparison of the incidence after the first and second vaccine doses (21 days apart); by calculating the standardized incidence ratio of the observed-to-expected incidence within 21 days after the first dose and 30 days after the second dose, independent of certainty of diagnosis; and by calculating the rate ratio 30 days after the second dose as compared with unvaccinated persons. RESULTS: Among 304 persons with symptoms of myocarditis, 21 had received an alternative diagnosis. Of the remaining 283 cases, 142 occurred after receipt of the BNT162b2 vaccine; of these cases, 136 diagnoses were definitive or probable. The clinical presentation was judged to be mild in 129 recipients (95%); one fulminant case was fatal. The overall risk difference between the first and second doses was 1.76 per 100,000 persons (95% confidence interval [CI], 1.33 to 2.19), with the largest difference among male recipients between the ages of 16 and 19 years (difference, 13.73 per 100,000 persons; 95% CI, 8.11 to 19.46). As compared with the expected incidence based on historical data, the standardized incidence ratio was 5.34 (95% CI, 4.48 to 6.40) and was highest after the second dose in male recipients between the ages of 16 and 19 years (13.60; 95% CI, 9.30 to 19.20). The rate ratio 30 days after the second vaccine dose in fully vaccinated recipients, as compared with unvaccinated persons, was 2.35 (95% CI, 1.10 to 5.02); the rate ratio was again highest in male recipients between the ages of 16 and 19 years (8.96; 95% CI, 4.50 to 17.83), with a ratio of 1 in 6637. CONCLUSIONS: The incidence of myocarditis, although low, increased after the receipt of the BNT162b2 vaccine, particularly after the second dose among young male recipients. The clinical presentation of myocarditis after vaccination was usually mild.

Impact of right ventricular volumes on the outcomes of TAVR: a volumetric analysis of preprocedural computed tomography.

AIMS: The aim of this study was to assess the prognostic implications of increased right ventricle volume index (RVVI) using cardiac-gated computed tomography angiography (CCTA) data among patients undergoing transcatheter valve replacement (TAVR). METHODS AND RESULTS: CCTA of 323 patients who underwent TAVR at Stanford University Medical Center (CA, USA) and Tel Aviv Medical Center (Israel) between 2013 and 2016 was analysed by an automatic four-chamber volumetric software and grouped into quartiles according to RVVI. Higher one-year mortality rates were noted for the upper quartiles - 5%, 4.9%, 8.6%, and 16% (p=0.039), in Q1 <59 ml/m2, Q2 59-69 ml/m2, Q3 69-86 ml/m2, and Q4 >86 ml/m2, respectively. However, the differences were not significant after propensity score adjustments. Sub-analyses of Q1 demonstrated an escalating risk for one-year mortality in concordance to RVVI: HR 2.28, HR 2.76, and HR 4.7, for the upper 25th, 15th, and 5th percentiles, respectively (p<0.05 for all comparisons). After propensity score adjustments for clinical and echocardiographic characteristics, only the upper 5th percentiles (RVVI >120 ml/m2) retained statistical significance (HR 2.82, 95% CI: 1.02-7.78, p=0.045). Notably, 68.7% of patients from this group were considered low-intermediate risk for surgery. CONCLUSIONS: Cardiac volumetric data by CCTA performed for procedural planning may help to predict outcome in patients undergoing TAVR.

Endovascular brachytherapy for extensive right-heart and pulmonary artery sarcoma - a case report.

PURPOSE: Primary sarcoma of the heart is a rare but devastating tumor. Median survival with conventional treatment is 8-12 months. When resection is not feasible, patients often succumb to heart failure secondary to obstruction of blood flow, valve dysfunction, chamber compression or conduction abnormalities. Palliative treatment options include systemic chemotherapy and external beam irradiation. We herein describe a novel technique using endovascular brachytherapy, aiming at reducing tumor mass, alleviating right ventricular pressure overload and at the same time keeping the option of R0 resection viable. MATERIAL AND METHODS: A 35-year-old man was diagnosed with a non-resectable high-grade intimal sarcoma of the right ventricle (RV), main pulmonary artery (PA) and right PA. After three cycles of doxorubicin and ifosfamide, the patient's symptoms of right heart failure worsened. Imaging documented tumor progression and supra-systemic pulmonary artery pressure. Through a trans-femoral venous access, a brachytherapy sleeve was placed in the RV and main and right PA. A dose of 20 Gy was delivered over a period of ten minutes. RESULTS: The patient had an uneventful course and was discharged home 24 hours after the procedure. Ten months after brachytherapy, repeat imaging demonstrated a significant reduction in tumor volume and an increase in pulmonary artery cross-sectional area with a marked reduction of pulmonary artery pressure, leading to a complete resolution of heart failure symptoms. CONCLUSIONS: Endovascular brachytherapy is a novel, safe and effective therapeutic modality for non-resectable primary cardiac sarcomas either for palliation of obstruction, or tumor mass reduction to allow complete resection.

Very Small Left Atrial Volume as a Marker for Mortality in Patients Undergoing Nongated Computed Tomography Pulmonary Angiography.

OBJECTIVES: To evaluate the association between very small left atria (VSLA) on nongated computed tomography pulmonary angiography (CTPA) and mortality in patients without pulmonary embolism (PE). METHODS: Patients who underwent nongated CTPA between 2011 and 2015 in order to rule out PE, and had an echocardiogram within 24 h of the CTPA, were retrospectively identified. The left atrial volume of nongated CTPA was calculated using automatic 4-chamber volumetric analysis software. The association between the lowest 5th percentile of the left atrial volume index, referred to as the VSLA group, and mortality was investigated after adjustment for age, gender, background diseases, and laboratory values. RESULTS: The study cohort included 241 patients. Patients with VSLA had a left atrial volume index <24 mL/m2 (n = 11). Demographics and background diseases did not differ between the study groups. The median follow-up was 22.7 months (IQR 0.03-54.3). VSLA was an independent predictor of mortality (HRadj = 3.6; 95% CI 1.46-8.87; p = 0.005), along with malignancy (HRadj = 2.28; 95% CI 1.32-3.93; p = 0.003) and lower hemoglobin (HRadj = 0.86; 95% CI 0.76-0.99; p = 0.032). CONCLUSIONS: Our findings suggest that VSLA on nongated CTPA may serve as a marker for mortality. The use of CTPA volumetric analysis can help risk stratification in patients with dyspnea and no PE.

An association between volumes of the cardiac chambers and troponin levels in individuals submitted to cardiac coronary computed tomography.

BACKGROUND: Previous echocardiographic studies have revealed an association between enlarged cardiac chamber volumes and elevated troponin concentrations. An automatic 4-chamber volumetric analysis tool was adopted to investigate this association in patients who underwent cardiac-gated computed tomography angiography (CCTA). HYPOTHESIS: We hypothesized that troponin concentration within the normal range correlates with cardiac chambers' volumes. METHODS: Serum troponin was obtained from 157 ambulatory patients before undergoing CCTA for nonacute coronary artery evaluation. Volumes of the cardiac chambers and the left ventricular mass were automatically analyzed and indexed to body surface area. Patients with a troponin concentrations within the upper quartile (>0.007 ng/mL, n = 39) were compared to patients with a troponin concentrations within the 3 lower quartiles of troponin concentrations (≤0.007 ng/mL, n = 118). RESULTS: None of the patients had a troponin concentration >0.05 ng/mL (the 99th percentile of the general population). There were no significant differences in baseline characteristics between the groups. There were significant correlations between troponin and ventricular volumes after adjustments for age and gender. In an analysis that included 107 patients without any known heart diseases, including those pathological findings in the current CCTA, there were significant correlations between troponin and the left and right ventricular volumes after adjustments for age, gender, and baseline characteristics (odds ratio [OR]: 1.08, 95% confidence interval [CI]: 1.03-1.14, P = 0.002 and OR: 1.11, 95% CI: 1.04-1.19, P = 0.002; respectively). CONCLUSIONS: Using the technology of automatic volumetric analysis in individuals undergoing CCTA, an association between larger right and left cardiac chambers and higher levels of troponin concentration was shown.

Left atrial appendage and pulmonary artery anatomic relationship by cardiac-gated computed tomography: Implications for late pulmonary artery perforation by left atrial appendage closure devices.

BACKGROUND: Delayed pulmonary artery (PA) perforation and tamponade caused by implantable left atrial appendage (LAA) closure devices has been reported in patients with close proximity between these structures. The LAA and PA anatomic relationship (LAA-PAar) has not been analyzed systematically. OBJECTIVE: The purpose of this study was to identify LAA-PAar variants potentially susceptible to this complication using cardiac-gated computed tomography angiography. METHODS: We studied 100 consecutive patients with atrial fibrillation undergoing cardiac-gated computed tomography angiography of the left atrium. The LAA-PAar was classified into 3 types on the basis of the location, length, and thickness of the segment of contact between the PA and/or its branches and the LAA: type 1, no contact; type 2, contact involving the proximal LAA (defined as the proximal 15 mm extending into the LAA from its ostium, or the LAA proximal to the first major bend arising <15 mm from the ostium); and type 3, contact limited to the distal LAA. RESULTS: LAA-PAar types 1, 2, and 3 were present in 7 (7%), 28 (28%), and 65 (65%) patients, respectively. For LAA-PAar type 2, the mean contact segment thickness and length were 0.6 ± 0.3 and 18.1 ± 10.6 mm, respectively. For LAA-PAar type 3, the distance between the LAA orifice and the segment of contact was <30 mm in 52 patients (80%). CONCLUSION: In this series, the LAA came in direct contact with the main PA in the majority of patients. Contact involved the proximal LAA (where the fixation components of most LAA closure devices are positioned) in 28% of patients, posing potential vulnerability to PA perforation.

Significance of reflux of contrast medium into the inferior vena cava on computerized tomographic pulmonary angiogram.

Reflux of contrast medium into the inferior vena cava (IVC) is often detected on computerized tomographic pulmonary angiogram. The potential clinical implications and associated diagnoses of this finding have not been established. We investigated the prevalence and significance of reflux of contrast medium into the IVC in a large cohort of patients evaluated for possible pulmonary embolism (PE) by computerized tomographic pulmonary angiography. We retrospectively reviewed 1,065 consecutive computerized tomographic pulmonary angiographic examinations performed from January 1, 2007 through January 7, 2008 for the presence of reflux. Degree of reflux into the IVC and hepatic veins was graded from 1 (none) to 6 (severe). Patients' charts were reviewed for diagnoses during the index hospitalization and for background diseases. These clinical data were correlated with the reflux grade. The final study included 967 computerized tomographic pulmonary angiographic scans of 367 men and 600 women (mean age 62 ± 20 years, range 17 to 103). Almost 1/2 (480, 49.6%) had grade 1, 310 (32.1%) had grades 2 to 3, and 177 (18.3%) had grades 4 to 6. Multivariate logistic regression found that pulmonary hypertension, history of congestive heart failure, chronic atrial fibrillation, and acute PE were associated with extensive reflux (grades 4 to 6) with odds ratios (95% confidence intervals) of 5.4 (3.0 to 9.9, p <0.001), 3.7 (2.3 to 6.1, p <0.001), 2.3 (1.0 to 5.3, p = 0.044), and 1.8 (1.2 to 2.9, p = 0.011), respectively. Interobserver agreement between the 2 readers for reflux grading was good (kappa = 0.77). In conclusion, extensive reflux of contrast medium into the IVC detected on computerized tomographic pulmonary angiogram may serve as a pathophysiologic marker of right heart dysfunction, specifically pulmonary hypertension, congestive heart failure, chronic atrial fibrillation, or PE.