Double aortic arch: an elusive diagnosis in a child with CHD.

An 18-month-old male with pulmonary atresia and ventricular septal defect presented with stridor after neonatal systemic-to-pulmonary artery shunt surgery, that persisted on follow-up. CT angiography revealed a vascular ring with balanced double aortic arch.

CMR for Identifying the Substrate of Ventricular Arrhythmia in Patients With Normal Echocardiography.

OBJECTIVES: This study sought to determine whether cardiac magnetic resonance (CMR) may identify structural heart disease (SHD) in patients with ventricular arrhythmia who had echocardiography ruled out pathological findings. BACKGROUND: Approximately one-half of sudden cardiac deaths are attributable to malignant VA. Echocardiography is commonly used to identify SHD that is the most frequent substrate of VA. METHODS: A single-center prospective study was conducted in consecutive patients with significant VA, categorized as >1,000 but <10,000 ventricular ectopic beats [VEBs]/24 h; ≥10,000 VEBs/24 h; nonsustained ventricular tachycardia, sustained ventricular tachycardia, or a history of resuscitated cardiac arrest, and no pathological findings at echocardiography, requiring a clinically indicated CMR. Primary endpoint was CMR detection of SHD. Secondary endpoints were a composite of CMR detection of SHD and abnormal findings not specific for a definite SHD diagnosis. RESULTS: A total of 946 patients were enrolled (mean 41 ± 16 years of age; 64% men). CMR studies were used to diagnose SHD in 241 patients (25.5%) and abnormal findings not specific for a definite SHD diagnosis in 187 patients (19.7%). Myocarditis (n = 91) was the more frequent disease, followed by arrhythmogenic cardiomyopathy (n = 55), dilated cardiomyopathy (n = 39), ischemic heart disease (n = 22), hypertrophic cardiomyopathy (n = 13), congenital cardiac disease (n = 10), left ventricle noncompaction (n = 5), and pericarditis (n = 5). The strongest univariate and multivariate predictors of SHD on CMR images were chest pain (odds ratios [OR]: 2.52 and 2.38, respectively) and sustained ventricular tachycardia (ORs: 2.67 and 2.23, respectively). CONCLUSIONS: SHD was able to be identified on CMR imaging in a sizable number of patients with significant VA and completely normal echocardiography. Chest pain and sustained ventricular tachycardia were the strongest predictors of positive CMR imaging results.

CT angiography prior to TAVI procedure using third-generation scanner with wide volume coverage: feasibility, renal safety and diagnostic accuracy for coronary tree.

OBJECTIVE:: To evaluate feasibility, image quality and accuracy of a reduced contrast volume protocol for pre-procedural CT imaging in transcatheter aortic valve implantation (TAVI) using a third generation wide array CT scanner. METHODS:: 115 consecutive patients (51F, mean age 82.5 ± 6.2 y, mean BMI 26.7 ± 3.6) referred for TAVI were examined with wide-array CT scanner with a combined scan protocol and a total amount of 50 ml contrast agent. A 4-point visual scale (4-1) was used to assess image quality . Contrast attenuation values (HU) and contrast-to-noise ratio (CNR) were measured at the level of the aortic root, ascending/descending aorta, subrenal aorta and at the level of right and left common femoral arteries. Coronary tree was assessed and compared with invasive coronary angiography (ICA). Aortic annulus measurements were compared with final procedural results. Patients creatinine was monitored at the baseline and 72 h after procedure. RESULTS:: Median quality score value was >3. Mean CNR at the level of the aortic root, ascending/descending aorta, subrenal aorta and at the level of right and left common femoral arteries were 14.8 ± 2.3, 15.7 ± 1.7, 14.9 ± 3.1, 15.8 ± 4.7, 20.3 ± 9.9, 20.8 ± 6.9 respectively. Only 1 patient had moderate paravalvular regurgitation. In comparison with ICA for coronary assessment CTA showed in a segment based analysis sensitivity, specificity, negative predictive value, positive predictive value and accuracy of 97, 85, 99,62 and 88% respectively. Mean creatinine before CT and 72 h after procedure were 1.21 ± 0.52 and1.22 ± 0.49 mg dl-1. Mean DLP was 442.4 ± 21.2 mGy/cm. CONCLUSION:: CT with low contrast volume is feasible and clinically useful, allowing precise pre-procedural TAVI planning with accurate assessment of coronary tree. ADVANCES IN KNOWLEDGE:: third generation CT scanner with whole heart coverage allows examinations for assessment of aorta and coronary arteries in TAVI planning using low dose of contrast medium maintaining good quality and high diagnostic accuracy.