Gabriella Napoli

Evolution of aortic dissection after surgical repair

Patients after aortic dissection repair still have long-term unfavorable prognosis and need careful monitoring. The purpose of this study was to analyze the evolution of aortic dissection after surgical repair in correlation to anatomic changes emerging from systematic magnetic resonance imaging (MRI) follow-up. Between January 1992 and June 1998, 70 patients underwent surgery for type A aortic dissection. Fifty-eight patients were discharged from the hospital (17% operative mortality) and were followed by serial MRI for 12 to 90 months after surgery. In all, 436 postoperative MRI examinations were analyzed. In 13 patients (22.5%) no residual intimal flap was identified, whereas 45 patients (77.5%) presented with distal dissection, with a partial thrombosis of the false lumen in 24. The yearly aortic growth rate was maximum in the descending aortic segment (0.37 +/- 0.43 cm) and was significantly higher in the absence of thrombus in the false lumen (0.56 +/- 0.57 cm) (p <0.05). There were 4 sudden deaths, with documented aortic rupture in 2. Sixteen patients underwent reoperation for expanding aortic diameter. In all but 1 patient, a residual dissection was present (in 13 without any thrombosis of the false lumen). Close MRI follow-up in patients after dissection surgical repair can identify the progression of aortic pathology, providing effective prevention of aortic rupture and timely reoperation. Thrombosis of the false lumen appears to be a protective factor against aortic dilation.

Assessment of restrictive cardiomyopathy of amyloid or idiopathic etiology by magnetic resonance imaging.

This study was designed to assess the role of magnetic resonance imaging in the differential diagnosis of amyloid and idiopathic etiology of cardiomyopathy. This technique demonstrated the capability to differentiate the 2 forms, providing high-resolution evaluation of the myocardial wall and detecting the infiltrative pathology by tissue characterization.

Magnetic Resonance Imaging Evaluation of Aortic Elastic Properties as Early Expression of Marfan Syndrome

In Marfan syndrome, early identification and treatment of aortic involvement could improve prognosis, but clinical diagnosis may be difficult at a young age, before aortic dilation occurs. The aim of this study was to evaluate biomechanical aortic properties in Marfan patients and in their relatives to identify an early index of aortic involvement. A magnetic resonance imaging (MRI) morphologic and functional study of the thoracic aorta was performed in 20 Marfan patients, 15 family members, and 14 healthy volunteers as a control group. The aorta was imaged in the oblique sagittal plane by spin-echo sequence. A high-resolution gradient-echo sequence was then applied in the axial plane at the level of ascending supravalvular aorta to evaluate aortic distensibility. Aortic distensibility (mm Hg(-1) was significantly different in the three groups (ANOVA, p = 0.0001). Aortic distensibility was sensibly reduced in Marfan patients (0.0085 +/- 0.006 vs. 0.025 +/- 0.006 control group, p < 0.05). No significant correlation was found between aortic area and distensibility. Aortic distensibility was reduced also in family members (0.016 +/- 0.011 vs. 0.025 +/- 0.006 control group, p < 0.05). Among them, 4 subjects showed aortic diameters to the upper limit of the normal range, whereas the other 11 presented normal aortic diameters. Intraobserver and interobserver reproducibility for diastolic measurement was 1.2% and 0.4%, respectively, and 1.1% and 0.3%, respectively, for systolic measurement. MRI is an accurate technique in detecting abnormal aortic elastic properties in Marfan patients. Abnormal ascending aorta distensibility may constitute an index of early aortic involvement before dilation occurs.

Lung perfusion in patients with pulmonary hypertension: comparison between MDCT pulmonary angiography with minIP reconstructions and 99mTc-MAA perfusion scan.

Objectives:Alterations in lung perfusion are a well-known feature of pulmonary hypertension (PH) seen on nuclear medicine studies. Abnormal radiotracer distribution in patients with PH may be caused by arterial thromboembolic occlusion, like in chronic thromboembolic pulmonary hypertension, by parenchymal destruction as in interstitial lung disease and pulmonary emphysema or by distal arteriopathy, like in idiopathic pulmonary arterial hypertension and other nonembolic forms. The different imaging pattern on radionuclide perfusion studies represents an important element for differential diagnosis. The aim of this study was to evaluate minimum intensity projection (minIP) images as an alternative to perfusion scintigraphy. We compared lung parenchyma attenuation patterns as depicted in minIP reconstructions with scintigraphic findings of lung perfusion in patients affected by pulmonary hypertension from various etiologies. Methods:One hundred and seven consecutive patients affected by PH of different etiology (37 of those had chronic thromboembolic pulmonary hypertension) who had undergone both multidetector computed tomography pulmonary angiography and 99mTc-MAA perfusion scan were included. Five-millimeter thickness contiguous axial, coronal, and sagittal minIP images were reconstructed from the contrast enhanced computed tomography datasets. Two radiologists evaluated the images and qualitatively graded pulmonary attenuation as homogeneous, inhomogeneous with nonsegmental patchy defects, or inhomogeneous with segmental defects. The presence of parenchymal and pleural alterations was recorded. MinIP perfusion grading results were then compared with those of perfusion scintigraphy. Results:In 87 of 107 patients (81.3%), the attenuation pattern seen on minIP images (39 homogeneous patterns, 13 with nonsegmental patchy defects, and 39 with segmental defects) correlated with the nuclear medicine scans. In the remaining 20 patients (18.7%), the imaging pattern was discordant because of 7 false-positive and 2 false-negative thromboembolic patterns at minIP and 11 false-positive thromboembolic patterns at perfusion scan. Air-trapping and parenchymal disease caused false-positive findings at minIP and perfusion scans, respectively. The sensitivity and specificity of minIP in detection of a chronic thromboembolic perfusion pattern were 94.5% and 90%, whereas perfusion scan had 100% sensitivity and 84% specificity. Conclusion:MinIP reconstructions can identify different patterns of pulmonary parenchymal attenuation, which show high concordance with perfusion patterns seen on radionuclide studies in patients with pulmonary hypertension. MinIP is a promising technique to evaluate lung perfusion in PH and may be used as an alternative to scintigraphy in the diagnostic work-up of these patients.

Evolution of post-traumatic aortic aneurysm in the subacute phase: magnetic resonance imaging follow-up as a support of the surgical timing

OBJECTIVES A recent surgical series documented that in traumatic aortic rupture (TAR) a surgical repair postponed to the treatment of associated lesions reduced operative and overall mortality. Nevertheless some isolated cases may develop to free rupture. Until now, no imaging follow-up studies of post-traumatic aortic lesions have been reported in the early stage. The aim of this study is to analyze the behaviour of traumatic aortic ruptures in the subacute phase, in order to detect the morphological characteristics of unstable post-traumatic aneurysms. METHODS Twenty-five consecutive patients affected by traumatic aortic rupture (one intimal hemorrhage, 19 partial lesions and five circumferential lesions) were admitted to the department of cardiac surgery. Magnetic resonance imaging (MRI) was the imaging method used to confirm the diagnosis. No one was operated on during the acute phase. All patients were treated with beta-blockers and vasodilators as well as limited fluid administration. Delayed surgery was carried out in 18 patients at 243 days (+/-127), after the resolution of associated lesions. A scheduled MRI follow-up was performed at 7, 15 and 30 days and immediately before the operation. The parameters examined were increase of post-traumatic aneurysm, increase of periaortic hematoma and modification of the thoracic associated lesions. RESULTS At 30 days a 3.0 +/- 3.7 mm median increase of the aneurysm was observed, while in the subsequent period the lesions became substantially stable, resulting in a 4.4 +/- 3.6 mm increment at the end of the follow-up. The circumferential lesions presented a higher increment with respect to the partial lesions. In three cases an augmentation of 6, 7 and 12 mm was detected and surgical repair was anticipated. In 13 cases a periadventitial hematoma surrounding the aortic aneurysm decreased through the time. One case of intimal hemorrhage healed spontaneously, with no aneurysm formation. Thoracic associated lesions (pleural and pericardial effusions, rib fractures, lung focal contusions and two cases of ARDS) resolved at 30-60 days. CONCLUSIONS Despite common knowledge, considering TAR highly evolutive in the acute and subacute phase, this study demonstrated that this pathological entity is relatively stable if a proper pharmacological treatment is administrated. MRI follow-up is recommended in order to detect isolated cases of unstable aneurysm.

Imaging of thoracic injuries

Diagnostic imaging plays a fundamental role in the evaluation of patients who sustain chest trauma, which is associated with high morbidity and mortality and is the leading cause of death in patients under 45 years old and the fourth cause of death in Western countries.

Cardiac anomalies in Turner Syndrome.

This is the case of a 30-year-old woman with Turner Syndrome, with Mosaicism, exhibiting a bicuspid aortic valve with aortic stenosis, ascending aortic dilatation, pseudocoarctation of the aorta, left superior vena cava and lusoria subclavian artery. The successful surgical procedure consisted of the replacement of the aortic root and ascending aorta with a composite valved graft.