Left ventricular fibro-fatty replacement in arrhythmogenic right ventricular dysplasia/cardiomyopathy: prevalence, patterns, and association with arrhythmias.

BACKGROUND: Left ventricular (LV) fibrofatty infiltration in arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C) has been reported, however, detailed cardiovascular magnetic resonance (CMR) characteristics and association with outcomes are uncertain. We aim to describe LV findings on CMR in ARVD/C patients and their relationship with arrhythmic outcomes. METHODS: CMR of 73 subjects with ARVD/C according to the 2010 Task Force Criteria (TFC) were analyzed for LV involvement, defined as ≥ 1 of the following features: LV wall motion abnormality, LV late gadolinium enhancement (LGE), LV fat infiltration, or LV ejection fraction (LVEF) < 50%. Ventricular volumes and function, regional wall motion abnormalities, and the presence of ventricular fat or fibrosis were recorded. Findings on CMR were correlated with arrhythmic outcomes. RESULTS: Of the 73 subjects, 50.7% had CMR evidence for LV involvement. Proband status and advanced RV dysfunction were independently associated with LV abnormalities. The most common pattern of LV involvement was focal fatty infiltration in the sub-epicardium of the apicolateral LV with a "bite-like" pattern. LGE in the LV was found in the same distribution and most often had a linear appearance. LV involvement was more common with non-PKP2 genetic mutation variants, regardless of proband status. Only RV structural disease on CMR (HR 3.47, 95% CI 1.13-10.70) and prior arrhythmia (HR 2.85, 95% CI 1.33-6.10) were independently associated with arrhythmic events. CONCLUSION: Among patients with 2010 TFC for ARVD/C, CMR evidence for LV abnormalities are seen in half of patients and typically manifest as fibrofatty infiltration in the subepicardium of the apicolateral wall and are not associated with arrhythmic outcomes.

Fibrotic Lung Disease at CT Predicts Adverse Outcomes in Patients Undergoing Transcatheter Aortic Valve Replacement.

PURPOSE: To evaluate the relationship between CT findings of diffuse lung disease and post-transcatheter aortic valve replacement (TAVR) outcomes. MATERIALS AND METHODS: Retrospective review of pre-TAVR CT scans obtained during 2012-2017 was conducted. Emphysema, reticulation, and honeycombing were separately scored using a five-point scale and applied to 10 images per examination. The fibrosis score was the sum of reticulation and honeycombing scores. Lung diseases were also assessed as dichotomous variables (zero vs nonzero scores). The two outcomes evaluated were death and the composite of death and readmission. RESULTS: The study included 373 patients with median age of 84 years (age range, 51-98 years; interquartile range, 79-88 years) and median follow-up of 333 days. Fibrosis and emphysema were present in 66 (17.7%) and 95 (25.5%) patients, respectively. Fibrosis as a dichotomous variable was independently associated with the composite of death and readmission (hazard ratio [HR], 1.54; P = .030). In those without known chronic lung disease (CLD) (HR, 3.09; P = .024) and those without airway obstruction, defined by a ratio of forced expiratory volume in 1 second to the forced vital capacity greater than or equal to 70% (HR, 1.67, P = .039), CT evidence of fibrosis was a powerful predictor of adverse events. Neither emphysema score nor emphysema as a dichotomous variable was an independent predictor of outcome. CONCLUSION: The presence of fibrosis on baseline CT scans was an independent predictor of adverse events after TAVR. In particular, fibrosis had improved predictive value in both patients without known CLD and patients without airway obstruction.Supplemental material is available for this article.© RSNA, 2020.

High-pitch non-gated scans on the second and third generation dual-source CT scanners: comparison of coronary image quality.

OBJECTIVE: To examine differences in image quality of the coronary arteries when performing high-pitch non-electrocardiography (ECG)-gated scans on the second-generation (2G) and third-generation (3G) dual-source CT scanners. METHODS: We retrospectively examined patients with high-pitch non-ECG-gated CT angiography (CTA) of the chest or chest/abdomen/pelvis. Outpatient scans from 59 patients in the 3G high-pitch group and 53 patients in the 2G high-pitch group were included. Two blinded cardiac imagers independently scored the coronary image quality using a 4-point Likert scale (from completely diagnostic to completely non-diagnostic) and evaluated the presence of coronary artery disease. RESULTS: Diagnostic image quality of the coronaries in high-pitch CTA exams using 3G scanner was improved compared to 2G scanner, both on a per-vessel basis (45-94% versus 23-86%) and on a per-study basis (34% versus 14%). The 3G group showed a statistically significant improvement in image quality when evaluating the left main coronary, right coronary, and overall coronary arteries. Coronary artery disease was detected in 65% of high-pitch scans. Radiation doses in terms of CTDIvol and DLP were lower for 3G high-pitch scans (7.5 mGy and 491 mGy∗cm) compared to 2G high-pitch scans (14.8 mGy and 911 mGy∗cm). CONCLUSIONS: We found a higher proportion of diagnostic image quality of the coronary arteries in high-pitch non-ECG-gated CTA exams using a 3G dual-source CT scanner, compared to 2G. In scans with diagnostic image quality, underlying coronary artery disease may be confidently diagnosed and should prompt considerations for further management in the appropriate clinical setting.

Pulmonary venous anomalies causing misdiagnosis of pulmonary arteriovenous malformations.

PURPOSE: To investigate pulmonary venous anomaly as a cause of pulmonary arteriovenous malformation (PAVM) misdiagnosis. MATERIALS AND METHODS: We reviewed adult patients within a 7.5-year period with CT scans initially diagnosed with PAVM and subsequent conventional pulmonary angiograms. RESULTS: Pulmonary arteriography showed no PAVM on arterial phase for 10 out of 99 patients, comprising the misdiagnosed group. Four misdiagnosed patients had pulmonary venous anomalies and six had nodular lesions on CT. CONCLUSION: Pulmonary venous anomalies are vascular mimics of PAVMs that may lead to misdiagnosis. Optimal CT technique and careful imaging review are necessary to minimize inappropriate invasive angiography.

Evaluation of Coronary Artery Disease and Coronary Anomalies with a Handheld Smartphone.

The purpose of this study was to determine the diagnostic accuracy of an iPhone for evaluation of the coronary arteries on coronary CT angiography (CTA) in comparison to a standard clinical workstation. Fifty coronary CTA exams were selected to include a range of normal and abnormal cases including both coronary artery disease (CAD) of varying severity and coronary artery anomalies. Two cardiac radiologists reviewed each exam on a standard clinical workstation initially and then on an iPhone 6 after a washout period. Coronary stenosis was evaluated on a 4-point scale and presence of coronary anomalies was recorded. Two additional cardiac radiologists reviewed all cases in consensus on the standard workstation and these results were used as the reference standard. When reader results were compared to the reference standard, there was no significant difference in agreement for per-vessel stenosis scores using either the iPhone or standard clinical workstation. The intraobserver intertechnology agreement on a per-vessel basis for obstructive CAD were 97.4% (299/307, kappa = 0.777) and 97.5% (317/325, kappa = 0.804) for the two readers. All cases of coronary anomalies were identified by both readers regardless of the device used. Coronary CTA examinations can be interpreted on a smartphone with diagnostic accuracy comparable to a standard workstation. 3D visualization app on the iPhone may facilitate urgent coronary CTA review when a workstation is not available.

Role of multidetector CT in assessment of repaired tetralogy of Fallot.

The population of adults with repaired tetralogy of Fallot (TOF) is growing, thanks to improvements in the surgical and medical management of this condition. Accordingly, late postrepair complications are important medical concerns in these individuals. Initial surgical repair of TOF typically occurs in infancy, consisting of patch repair of the ventricular septal defect (VSD) and relief of right ventricular outflow tract (RVOT) obstruction. Although patients may remain asymptomatic for several decades, the majority will have progressive pulmonic regurgitation that leads to right ventricular (RV) dilatation and functional deterioration. Other frequently seen complications include branch pulmonary artery stenosis, RVOT aneurysms, and recurrent VSDs. Cardiac computed tomography (CT) is widely available and, in some cases, is the imaging modality of choice for serial evaluation of TOF patients. CT is particularly useful when magnetic resonance (MR) imaging is contraindicated (eg, in patients with implantable cardiac devices). Unlike MR imaging, cardiac CT allows excellent visualization of endovascular stents and stent-mounted valves. Retrospective electrocardiographically gated cardiac CT can be used for accurate volumetric and functional analysis of the RV. Comprehensive serial evaluation will assist in determining the need for surgical pulmonary valve repair in the setting of progressive RV dysfunction. Three-dimensional volumetric images are useful for evaluation of stent integrity and aneurysm formation. The radiologist should be familiar with the anatomy of TOF, surgical interventions for repair, and postrepair complications encountered at follow-up imaging of these patients. By extracting the breadth of information obtained with cardiac multidetector CT, the radiologist can play an essential role in the management of adult patients with repaired TOF.