Total Anomalous Pulmonary Venous Connection in an Adult: Comprehensive Multimodality Evaluation

An unusual case of total anomalous pulmonary venous connection surviving to adulthood without surgical correction is presented. Transthoracic echocardiography first led to this diagnosis and magnetic resonance imaging refined the anatomic diagnosis leading to successful surgical correction.     

Non-Gadolinium-Enhanced 3-Dimensional Magnetic Resonance Angiography for the Evaluation of Thoracic Aortic Disease: A Preliminary Experience

We compared image quality and diagnostic accuracy of a noncontrast 3-dimensional magnetic resonance angiography (NC-MRA) technique (balanced steady-state free-precession sequence) to contrast-enhanced MRA (CE-MRA) for evaluation of thoracic aortic disease.The CE-MRA provides 3-dimensional high-resolution images of the thoracic aorta that are important in the evaluation of patients with aortic disease. However, recent concerns with the potential nephrotoxic effects of gadolinium contrast medium limit the application of CE-MRA for patients who have significant renal insufficiency.Twenty-one patients (mean age, 51 yr; 18 men) who underwent NC-MRA and CE-MRA for evaluation of thoracic aortic disease were retrospectively identified. Data sets were reviewed by 2 readers who were blinded to the patients'' information. The thoracic aorta was divided into 5 segments. Image quality and reader confidence for diagnosis of aortic pathology were rated on 5-point scales. The Wilcoxon matched-pairs signed rank test and the Student t test were used for comparisons.The NC-MRA identified all pathologic findings with 100% diagnostic accuracy and similar reader confidence, when compared with CE-MRA. Although overall image quality was not significantly different, superior image quality was observed at the aortic root (4.4 ± 0.8 vs 3.2 ± 0.9, P <0.0005) and ascending aorta (4.1 ± 1 vs 3.7 ± 0.9, P=0.05) respectively.In conclusion, NC-MRA is a useful alternative for evaluation and follow-up of thoracic aortic disease, especially for patients with poor intravenous access or contraindications to gadolinium use.Key words: Aneurysm, dissecting/diagnosis; aorta, thoracic/pathology; aortic aneurysm, thoracic/diagnosis; aortic diseases/diagnosis/radiography; artifacts; contrast media/toxici-ty; gadolinium/diagnostic use/toxicity; magnetic resonance angiography; retrospective studiesContrast-enhanced magnetic resonance angiography (CE-MRA) is often used for initial assessment and follow-up of thoracic aortic disease.^1,2 Fast, reproducible, 3-dimensional (3-D) high-resolution imaging of the thoracic aorta is essential for surgical planning and follow-up after intervention. Although computed tomographic angiography has advanced rapidly over the past few years and now can provide high-resolution images of the thoracic aorta, it has several drawbacks, including its use of ionizing radiation and nephrotoxic iodinated contrast agents and its inability to quantify blood flow. Contrast-enhanced MRA has such limitations as its need for intravenous gadolinium-chelate contrast, its frequent application without cardiac gating (which leads to motion artifacts), and its predominantly intraluminal imaging of the aorta³ (with restricted imaging of the aortic wall for the evaluation of mural and extraluminal disease such as intramural hematoma or vasculitis). Gadolinium--chelate contrast agents are far less likely to elicit allergic-type reactions than are iodinated contrast agents, and are, in general, considered safer for use in patients with impaired renal function. Recently, however, they have been associated with nephrogenic systemic fibrosis, a potentially life-threatening disease that chiefly affects patients on dialysis or with severe renal dysfunction.^4,5Electrocardiographic (ECG) gated 2-dimensional noncontrast imaging techniques, including spin-echo, gradient-echo, and time-of-flight pulse sequences, enable improved visualization of the aorta without need for contrast but are hampered by long-er imaging times and nonvolumetric data acquisition.⁶ Recently, a respiratory- and cardiac-gated, fat-suppressed, noncontrast 3-D magnetic resonance angiography (NC-MRA) technique (balanced steady-state free-precession sequence) has been developed for whole-heart imaging,^7,8 and this provides high and isotropic spatial resolution for the evaluation of coronary arteries.^9,10 It is unknown whether this technique can be applied to the imaging of various aortic diseases with reliable diagnostic accuracy, although recent preliminary results are promising.^11–13 The aim of this study was to examine our institution''s initial experience in comparing the image quality and diagnostic accuracy of NC-MRA to those of CE-MRA for the evaluation of the anatomy and pathology of the thoracic aorta and branch vessels.     

Extent of myocardial scarring on nonstress delayed-contrast-enhancement cardiac magnetic resonance imaging correlates directly with degrees of resting regional dysfunction in chronic ischemic heart disease

Background

Hyper-enhancement on delayed-enhancement magnetic resonance imaging (DE-MRI) is a marker of irreversible myocardial injury. Both reversible and irreversible ischemically injured regions of myocardium develop reductions in systolic function compared with unaffected regions. This study evaluated whether there is a relationship between myocardial hyper-enhancement from remote scarring on DE-MRI and the degree of myocardial circumferential shortening (%CS) as determined with dynamic MRI tissue tagging (TAG-MRI) in the setting of chronic ischemic heart disease (CIHD).

Methods

Thirty-five patients with CIHD and 8 control patients underwent nonstress, resting DE-MRI and TAG-MRI. A total of 168 CIHD and 96 control segments from the basal- and middle-thirds of the left ventricle (LV) were selected to achieve a balanced test set. With a 16-segment model, segmental myocardial scarring was graded on the basis of the amount of hyper-enhancement on DE-MRI. With TAG-MRI images, segmental %CS was calculated.

Results

Patients with CIHD had lower LV ejection fraction compared with the control patients (28% vs 67%). The %CS of normal segments was notably different from %CS of CIHD segments, regardless of the presence or absence of myocardial hyper-enhancement on DE-MRI. Among the CIHD segments, however, %CS correlated inversely with the amount of myocardial hyper-enhancement from scarring (P <.0001, r = −0.38).

Conclusions

On cardiac MRI for CIHD, myocardial hyper-enhancement correlates inversely with %CS, supporting the direct relationship between the amount of remote myocardial scarring determined with nonstress DE-MRI and baseline resting functional impairment.     

Coronary CTA assessment of coronary anomalies

Coronary anomalies occur in <1% of the general population and can range from a benign incidental finding to the cause of sudden cardiac death. The coronary anomalies are classified here according to the traditional grouping into those of origin and course, intrinsic arterial anatomy, and termination. Classic coronary anomalies of origin and course include those in which a coronary artery originates from the contralateral aortic sinus or the pulmonary artery with anomalous course. Single coronary artery anomalies, in which single coronary artery branches to supply the entire coronary tree, are also included in this category. Anomalies of intrinsic arterial anatomy are a broad class that includes myocardial bridges, coronary ectasia and aneurysms, subendocardial coursing arteries, and coronary artery duplication. Coronary anomalies of termination are those in which a coronary artery terminates in a fistulous connection to a great vessel or cardiac chamber. In the case of those anomalies associated with a risk of sudden cardiac death, the relevant imaging features on CT angiography (CTA) associated with poorer prognosis are reviewed. Recent guidelines and appropriateness criteria favor the use of coronary CTA for the evaluation of coronary anomalies. Although invasive angiography has historically been used to diagnose coronary anomalies, multidetector CT imaging techniques have now become an accurate noninvasive alternative. Cardiac CTA provides excellent spatial and temporal resolution, allowing accurate anatomical assessment of these anomalies.     

Cardiac tamponade masking clinical presentation and hemodynamic effects of papillary muscle rupture after acute myocardial infarction.

A 67-year-old woman sustained an acute lateral-wall myocardial infarction and was treated with thrombolytic therapy. Postinfarction hypotension developed 3 days later. Clinical findings at that time were consistent with cardiac tamponade, and an echocardiographic study revealed a moderate-sized pericardial effusion. She underwent urgent pericardiocentesis with transient improvement in hemodynamics, followed by deterioration associated with the development of acute pulmonary edema. Follow-up transesophageal echocardiographic imaging revealed papillary muscle rupture with severe mitral regurgitation. The patient underwent urgent surgical intervention consisting of coronary artery bypass grafting and mitral valve replacement. The presence of cardiac tamponade in this patient masked the clinical manifestations of papillary muscle rupture through the hemodynamic effect of tamponade physiology on mitral regurgitation.