Intraindividual Comparison of Dose Reduction and Coronary Calcium Scoring Accuracy Using Kilovolt-independent and Tin Filtration CT Protocols.

Purpose To investigate the ability of kilovolt-independent (hereafter, kV-independent) and tin filter spectral shaping to accurately quantify the coronary artery calcium score (CACS) and radiation dose reductions compared with the standard 120-kV CT protocol. Materials and Methods This prospective, blinded reader study included 201 participants (mean age, 60 years ± 9.8 [SD]; 119 female, 82 male) who underwent standard 120-kV CT and additional kV-independent and tin filter research CT scans from October 2020 to July 2021. Scans were reconstructed using a Qr36f kernel for standard scans and an Sa36f kernel for research scans simulating artificial 120-kV images. CACS, risk categorization, and radiation doses were compared by analyzing data with analysis of variance, Kruskal-Wallis test, Mann-Whitney test, Bland-Altman analysis, Pearson correlations, and κ analysis for agreement. Results There was no evidence of differences in CACS across standard 120-kV, kV-independent, and tin filter scans, with median CACS values of 1 (IQR, 0-48), 0.6 (IQR, 0-58), and 0 (IQR, 0-51), respectively (P = .85). Compared with standard 120-kV scans, kV-independent and tin filter scans showed excellent correlation in CACS values (r = 0.993 and r = 0.999, respectively), with high agreement in CACS risk categorization (κ = 0.95 and κ = 0.93, respectively). Standard 120-kV scans had a mean radiation dose of 2.09 mSv ± 0.84, while kV-independent and tin filter scans reduced it to 1.21 mSv ± 0.85 and 0.26 mSv ± 0.11, cutting doses by 42% and 87%, respectively (P < .001). Conclusion The kV-independent and tin filter research CT acquisition techniques showed excellent agreement and high accuracy in CACS estimation compared with standard 120-kV scans, with large reductions in radiation dose. Keywords: CT, Cardiac, Coronary Arteries, Radiation Safety, Coronary Artery Calcium Score, Radiation Dose Reduction, Low-Dose CT Scan, Tin Filter, kV-Independent Supplemental material is available for this article. © RSNA, 2024.

Myocardial Blood Flow Reserve, Microvascular Coronary Health, and Myocardial Remodeling in Patients With Aortic Stenosis.

BACKGROUND: Coronary microvascular function and hemodynamics may play a role in coronary circulation and myocardial remodeling in patients with aortic stenosis (AS). We aimed to evaluate the relationship between myocardial blood flow and myocardial function in patients with AS, no AS, and aortic valve sclerosis. METHODS AND RESULTS: We included consecutive patients who had resting transthoracic echocardiography and clinically indicated positron emission tomography myocardial perfusion imaging to capture their left ventricular ejection fraction, global longitudinal strain (GLS), and myocardial flow reserve (MFR). The primary outcome was major adverse cardiovascular event (all-cause mortality, myocardial infarction, or late revascularization). There were 2778 patients (208 with aortic sclerosis, 39 with prosthetic aortic valve, 2406 with no AS, and 54, 49, and 22 with mild, moderate, and severe AS, respectively). Increasing AS severity was associated with impaired MFR (P<0.001) and GLS (P<0.001), even when perfusion was normal. Statistically significant associations were noted between MFR and GLS, MFR and left ventricular ejection fraction, and MFR and left ventricular ejection fraction reserve. After a median follow-up of 349 (interquartile range, 116-662) days, 4 (7.4%), 5 (10.2%), and 6 (27.3%) patients experienced a major adverse cardiovascular event in the mild, moderate, and severe AS groups, respectively. In a matched-control analysis, patients with mild-to-moderate AS had higher rates of impaired MFR (52.9% versus 39.9%; P=0.048) and major adverse cardiovascular event (11.8% versus 3.0%; P=0.002). CONCLUSIONS: Despite lack of ischemia, as severity of AS increased, MFR decreased and GLS worsened, reflecting worse coronary microvascular health and myocardial remodeling. Positron emission tomography-derived MFR showed a significant independent correlation with left ventricular ejection fraction and GLS. Patients with prosthetic aortic valve showed a high prevalence of impaired MFR.

Diagnostic Value of Aortic Valve Calcification Levels in the Assessment of Low-Gradient Aortic Stenosis.

BACKGROUND: In patients with low-gradient aortic stenosis (AS) and low transvalvular flow, dobutamine stress echocardiography (DSE) is recommended to determine AS severity, whereas the degree of aortic valve calcification (AVC) supposedly correlates with AS severity according to current European and American guidelines. OBJECTIVES: The purpose of this study was to assess the relationship between AVC and AS severity as determined using echocardiography and DSE in patients with aortic valve area <1 cm2 and peak aortic valve velocity <4.0 m/s. METHODS: All patients underwent DSE to determine AS severity and multislice computed tomography to quantify AVC. Receiver-operating characteristics curve analysis was used to assess the diagnostic value of AVC for AS severity grading as determined using echocardiography and DSE in men and women. RESULTS: A total of 214 patients were included. Median age was 78 years (25th-75th percentile: 71-84 years) and 25% were women. Left ventricular ejection fraction was reduced (<50%) in 197 (92.1%) patients. Severe AS was diagnosed in 106 patients (49.5%). Moderate AS was diagnosed in 108 patients (50.5%; in 77 based on resting transthoracic echocardiography, in 31 confirmed using DSE). AVC score was high (≥2,000 for men or ≥1,200 for women) in 47 (44.3%) patients with severe AS and in 47 (43.5%) patients with moderate AS. AVC sensitivity was 44.3%, specificity was 56.5%, and positive and negative predictive values for severe AS were 50.0% and 50.8%, respectively. Area under the receiver-operating characteristics curve was 0.508 for men and 0.524 for women. CONCLUSIONS: Multi-slice computed tomography-derived AVC scores showed poor discrimination between grades of AS severity using DSE and cannot replace DSE in the diagnostic work-up of low-gradient severe AS.

Left Atrial Thrombus in the Setting of Mitral Stenosis.

A 56-year-old man with no significant past medical history presented with exertional shortness of breath. Echocardiogram, cardiac magnetic resonance, and computed tomography showed mitral stenosis and a left atrial thrombus. Left atrial thrombus formation is a well-known complication of severe mitral stenosis that can lead to systemic thromboembolism. The patient underwent mitral valve replacement, left atrial thrombus resection, and left atrial appendage closure that resulted in significant improvement in breathing.

AI-based, automated chamber volumetry from gated, non-contrast CT.

BACKGROUND: Accurate chamber volumetry from gated, non-contrast cardiac CT (NCCT) scans can be useful for potential screening of heart failure. OBJECTIVES: To validate a new, fully automated, AI-based method for cardiac volume and myocardial mass quantification from NCCT scans compared to contrasted CT Angiography (CCTA). METHODS: Of a retrospectively collected cohort of 1051 consecutive patients, 420 patients had both NCCT and CCTA scans at mid-diastolic phase, excluding patients with cardiac devices. Ground truth values were obtained from the CCTA scans. RESULTS: The NCCT volume computation shows good agreement with ground truth values. Volume differences [95% CI ] and correlation coefficients were: -9.6 [-45; 26] mL, r â€‹= â€‹0.98 for LV Total, -5.4 [-24; 13] mL, r â€‹= â€‹0.95 for LA, -8.7 [-45; 28] mL, r â€‹= â€‹0.94 for RV, -5.2 [-27; 17] mL, r â€‹= â€‹0.92 for RA, -3.2 [-42; 36] mL, r â€‹= â€‹0.91 for LV blood pool, and -6.7 [-39; 26] g, r â€‹= â€‹0.94 for LV wall mass, respectively. Mean relative volume errors of less than 7% were obtained for all chambers. CONCLUSIONS: Fully automated assessment of chamber volumes from NCCT scans is feasible and correlates well with volumes obtained from contrast study.

Multimodality Imaging of a Silent Killer.

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Direct Oral Anticoagulants Versus Vitamin K Antagonists in the Treatment of Left Ventricular Thrombi.

Left ventricular thrombi form due to the presence of Virchow's triad in patients with left ventricular systolic dysfunction. This complication increases the incidence of systemic embolization, hence anticoagulation is recommended to decrease this risk. Up to the present time, vitamin K antagonists are recommended by all societal guidelines for patients with left ventricular thrombi. Recently, several studies have investigated the role of different anticoagulants and yielded promising outcomes. This opinion article focuses on the evidence supporting vitamin K antagonists and direct oral anticoagulants in patients with left ventricular thrombi.

Left Atrial Appendage Closure During Cardiac Surgery for Atrial Fibrillation: A Meta-Analysis.

BACKGROUND: Left atrial appendage closure (LAAC) during cardiac surgery in atrial fibrillation (AF) patients has been investigated in multiple studies with variable safety and efficacy results. METHODS: A comprehensive review was performed of all studies comparing LAAC and placebo arm during cardiac surgery in AF patients. A random-effect model was used to calculate risk ratios, mean differences, and 95% confidence intervals. RESULTS: Five randomized controlled trials and 22 observational studies were included with a total of 540,111 patients. The LAAC group had significantly decreased postoperative stroke/embolic events as compared to the no LAAC group with all cardiac surgeries (3.74% vs 4.88%, p = 0.0002), isolated valvular surgery (1.95% vs 4.48%, p = 0.002). However, CABG insignificantly favored the LAAC group for stroke/embolic events (6.72% vs 8.30%, p = 0.07). There was no difference between both groups in all-cause mortality in the perioperative period (p = 0.42), but was significantly lower in the LAAC arm after two years (14.1% vs 18.3%, p = 0.02). There was no difference in major bleeding, all-cause rehospitalizations, or cross-clamp time between both groups (p = 0.53 and p = 0.45). The bypass and the cross-clamp time were longer in the LAAC group (4 and 9 min, respectively). CONCLUSION: In AF patients, LAAC during cardiac surgery had a decreased risk of stroke and long-term all-cause mortality. Additionally, there was no difference in major bleeding, all-cause rehospitalizations, or cross-clamp time.

Meta-Analysis of Valve-in-Valve Transcatheter Aortic Valve Implantation Versus Redo-surgical Aortic Valve Replacement in Failed Bioprosthetic Aortic Valve.

This meta-analysis was conducted to compare clinical outcomes of valve-in-valve transcatheter aortic valve implantation (ViV-TAVI) versus redo-surgical aortic valve replacement (Redo-SAVR) in failed bioprosthetic aortic valves. We conducted a comprehensive review of previous publications of all relevant studies through August 2020. Twelve observational studies were included with a total of 8,430 patients, and a median-weighted follow-up period of 1.74 years. A pooled analysis of the data showed no significant difference in all-cause mortality (OR 1.15; 95% CI 0.93 to 1.43; p = 0.21), cardiovascular mortality, myocardial infarction, permanent pacemaker implantation, and the rate of moderate to severe paravalvular leakage between ViV-TAVI and Redo-SAVR groups. The rate of major bleeding (OR 0.36; 95% CI 0.16 to 0.83, p = 0.02), procedural mortality (OR 0.41; 95% CI 0.18 to 0.96, p = 0.04), 30-day mortality (OR 0.58; 95% CI 0.45 to 0.74, p <0.0001), and the rate of stroke (OR 0.65; 95% CI 0.52 to 0.81, p = 0.0001) were significantly lower in the ViV- TAVI arm when compared with Redo-SAVR arm. The mean transvalvular pressure gradient was significantly higher post-implantation in the ViV-TAVI group when compared with the Redo-SAVR arm (Mean difference 3.92; 95% CI 1.97 to 5.88, p < 0.0001). In conclusion, compared with Redo-SAVR, ViV-TAVI is associated with a similar risk of all-cause mortality, cardiovascular mortality, myocardial infarction, permanent pacemaker implantation, and the rate of moderate to severe paravalvular leakage. However, the rate of major bleeding, stroke, procedural mortality and 30-day mortality were significantly lower in the ViV-TAVI group when compared with Redo-SAVR.

The Role of Direct Oral Anticoagulants Versus Vitamin K Antagonists in the Treatment of Left Ventricular Thrombi: A Meta-Analysis and Systematic Review.

BACKGROUND: Direct oral anticoagulants (DOACs) have a well-established role in the treatment of deep vein thrombosis and pulmonary embolism and in the reduction of thromboembolism in nonvalvular atrial fibrillation. However, limited evidence supports their role in patients with left ventricular thrombi. METHODS: The PubMed, EMBASE, and Cochrane databases were searched for relevant articles published from inception to 1 August 2020. We included studies evaluating the effect of DOACs versus vitamin K antagonists (VKAs) in patients with left ventricular thrombi. The primary outcome was thrombus resolution, and the secondary outcomes were major bleeding and stroke or systemic embolization (SSE). RESULTS: Five retrospective observational studies were included, with a total of 857 patients. VKAs and DOACs had a similar rate of thrombus resolution (odds ratio [OR] 0.97; 95% confidence interval [CI] 0.57-1.65; p = 0.90). Our analysis also demonstrated a similar rate of major bleeding (OR 0.62; 95% CI 0.27-1.44; p = 0.27) and SSE (OR 1.86; 95% CI 0.99-3.50; p = 0.05) between the two treatment groups. CONCLUSION: In patients with left ventricular thrombi, DOACs and VKAs are associated with similar rates of thrombus resolution, major bleeding, and SSE.

Anthracycline-induced cardiotoxicity: mechanisms of action, incidence, risk factors, prevention, and treatment.

Anthracycline is a mainstay in treatment of many cancers including lymphoma and breast cancer among many others. However, anthracycline treatment can be cardiotoxic. Although anthracycline-induced cardiotoxicity is dose dependent, it can also occur early at the onset of treatment and even up to several years following completion of treatment. This review article focuses on the understanding of mechanisms of anthracycline-induced cardiotoxicity, the treatments, and recommended follow-up and preventive approaches.

Meta-analysis Examining the Usefulness of Angiotensin Receptor blockers for the Prevention of Aortic Root Dilation in Patients With the Marfan Syndrome.

The Marfan syndrome (MFS) patients are highly predisposed to thoracic aortic aneurysm and/or dissection, with virtually every patient having evidence of aortic disease at some point during their lifetime. We conducted a meta-analysis to investigate the efficacy of angiotensin receptor blockers (ARBs) in slowing down the progression of aortic dilatation in MFS patients. PUBMED, EMBASE, and COCHRANE databases were searched for relevant articles published from inception to February 1, 2020. We included randomized clinical trials evaluating the effect of ARBs on aortic root size in patients with MFS with a follow-up period of at least 2.5 years. Seven studies were included with a total of 1,510 patients. Our analysis demonstrated a significantly smaller change in aortic root and ascending aorta dilation in the ARBs treated group when compared with placebo (mean difference 0.68; 95% confidence interval [CI] -1.31 to -0.04; p = 0.04, I2 = 94%, and mean difference -0.13, 95% CI -0.17 to -0.09; p < 0.00001, I2 = 0%, respectively). ARBs as an add-on therapy to beta-blockers resulted in a significantly smaller change in aortic root dilation when compared with the arm without ARBs (mean difference -2.06, 95% CI -2.54 to -1.58; p < 0.00001, I2 = 91%). However, there was no statistically significant difference in the number of clinical events (aortic complications/surgery) observed in the ARBs arm when compared with placebo (Risk ratio of 1.01, 95% CI 0.74 to 1.38; p = 0.94, I2 = 0%). In conclusion, ARBs therapy is associated with a slower progression of aortic root dilation when compared with placebo and as an addition to beta-blocker therapy.

Frequency of de novo atrial fibrillation in patients presenting with acute ischemic cerebrovascular stroke.

BACKGROUND: Atrial fibrillation (AF) affects millions of people worldwide and can remain undiagnosed for years. It is a major cause of cerebrovascular stroke (CVS); hence, early detection is extremely important in order to decrease the risk of CVS. We conducted a retrospective observational study looking into the prevalence of silent AF in 3299 patients admitted from January 2014 to December 2017 in a tertiary care stroke specialized center. Ischemic CVS was confirmed either by using multislice computed tomography (MSCT) or magnetic resonance imaging (MRI) of the brain. AF was diagnosed by electrocardiography (ECG) at the time of admission or during the hospital stay. Patients with a history of AF were excluded from the study. RESULTS: Of the 3299 patients admitted by acute ischemic CVS, 707 (21.43%) had a history of AF and thus were excluded from the study. Of the remaining 2592 patients eligible for the study, 1666 (64.27%) were males with a mean age of 56.06 years (± 16.01). A total of 2313 (89.24%) patients remained in sinus rhythm throughout the hospital stay, 211 (8.14%) patients were in AF on admission, and 68 (2.62 %) patients developed AF during their hospital stay. The total number of newly diagnosed patients with AF was 279 (10.76%). CONCLUSION: The prevalence of de novo atrial fibrillation in patients presented with acute cerebrovascular stroke is high. The implementation of good screening programs can significantly reduce the risk of disabilities and morbidities.

Carney Complex: A Rare Case of Multicentric Cardiac Myxoma Associated with Endocrinopathy.

Carney complex is a rare autosomal dominant disorder characterized by multiple tumors, including cardiac and extracardiac myxomas, skin lesions, and various endocrine disorders. We are reporting a 21-year-old female patient with past surgical history significant for excision of a cutaneous myxoma who presented with multicentric cardiac myxomas involving the four cardiac chambers. She also presented with endocrinal disorders in the form of an enlarged right lobe of the thyroid, hyperthyroid state, and an incidentally noted adrenal cyst; hence, she was diagnosed with carney complex syndrome.