Alberto Hidalgo

Ruling Out Coronary Artery Disease with Noninvasive Coronary Multidetector CT Angiography before Noncoronary Cardiovascular Surgery

PURPOSE To assess the usefulness of preoperative coronary computed tomographic (CT) angiography in the detection of coronary artery disease (CAD) in nonselected patients scheduled to undergo noncoronary cardiovascular surgery to avoid unnecessary invasive coronary angiography (ICA). MATERIALS AND METHODS The institutional review board approved the study protocol; informed consent was given. This prospective study involved 161 consecutive patients who underwent coronary calcium scoring and coronary CT angiography before undergoing noncoronary cardiovascular surgery. Seven patients were excluded because of contraindications to CT angiography. The major indication of noncoronary cardiovascular surgery was valvular heart disease (121 patients). Follow-up was performed at a median of 20 months to define ischemic events described as acute coronary syndrome or death secondary to acute coronary syndrome, arrhythmias, or cardiac failure. Multivariate analysis was performed to determine predictors of nondiagnostic coronary CT angiography. Kaplan-Meier analysis was performed to evaluate outcome at follow-up. RESULTS Twenty-one patients did not undergo surgery, which left 133 patients as the study group. Atrial fibrillation was present in 45 of 133 patients. The interquartile range of the Agatston coronary calcium score was 0-471. Coronary CT angiography was diagnostic in 108 of 133 patients. Of these, 93 of 108 had no significant CAD (≤ 50% stenosis), and noncoronary cardiovascular surgery was performed in them without preoperative ICA. No patients in this group had postoperative ischemic events at follow-up. Coronary CT angiography was nondiagnostic in 25 of 133 patients who were referred for preoperative ICA. Multivariate analysis showed Agatston score to be the only independent predictor of nondiagnostic coronary CT angiography (odds ratio = 1.002; 95% confidence interval: 1.001, 1.003; P = .001). The best Agatston score cutoff for diagnostic coronary CT angiography was 579. CONCLUSION In nonselected patients scheduled to undergo noncoronary cardiovascular surgery, preoperative coronary CT angiography was diagnostic in 81% of cases. Preoperative ICA could be safely avoided in patients without significant CAD by using coronary CT angiography. The Agatston score, but not the presence of atrial fibrillation, was an independent predictor of nondiagnostic coronary CT angiography. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100384/-/DC1.

Thin-Section CT Findings in Hematopoietic Stem Cell Transplantation Recipients with Respiratory Virus Pneumonia

OBJECTIVE The purpose of this study was to use serial thin-section CT scans to assess the incidence of respiratory viral infection and lung abnormalities in a large patient population at high risk of pulmonary complications. MATERIALS AND METHODS The study population consisted of 26 recipients of hematopoietic stem cell transplants who had proven respiratory viral pneumonia. In all cases, thin-section CT scans were obtained before fiberoptic bronchoscopy and bronchoalveolar lavage. The study included only patients in whom bronchoalveolar lavage fluid showed no evidence of organisms other than respiratory viruses. The CT scans were assessed for the presence, extent, and anatomic distribution of ground-glass attenuation, air-space consolidation, nodules, centrilobular branching structures (tree-in-bud), thickening of the bronchovascular bundles, and pleural effusion. RESULTS Areas of ground-glass attenuation were identified in 24 (92%) of 26 patients and were the only finding in eight patients. Multiple nodules, seen in 17 (65%) of 26 patients, measured 3-10 mm in diameter or were larger than 10 mm. The nodules had a centrilobular or random distribution. A tree-in-bud appearance was seen in six of the patients with centrilobular nodules. This pattern had a bilateral distribution and involved mainly the lower lung zones. CT revealed thickening of the bronchovascular bundles in 16 (61%) of the patients. Thickening was bilateral in 14 and unilateral in two patients. Bronchial wall thickening involved the lower lobes in six patients and had a patchy random distribution in the remaining nine patients. Air-space consolidation was present in nine (35%) of the cases. It had a lobular or subsegmental distribution in eight of the patients and a segmental distribution in one patient. Areas of consolidation were randomly distributed throughout the lungs in all cases. Less common findings included bilateral pleural effusion and bronchial dilatation. CONCLUSION Respiratory viral infection is common among adult recipients of hematopoietic stem cell transplants, occurring over a wide time span after transplantation. The presence of respiratory viral infection must be considered in any patient with new respiratory symptoms, fever, or findings at CT such as extensive or patchy areas of ground-glass opacities or a mixture of patterns, most commonly ground-glass attenuation, thickening of the bronchial walls, and multiple small nodules.

Predicting survival in adults with invasive aspergillosis during therapy for hematological malignancies or after hematopoietic stem cell transplantation: Single-center analysis and validation of the Seattle, French, and Strasbourg prognostic indexes.

In this retrospective monocenter study, we analyzed the outcomes of 130 adult hematological patients who developed a proven (n = 23), probable (n = 71), and possible (n = 36) invasive aspergillosis (IA) in a 13‐year period. Forty‐nine patients (38%) were recipients of an allogeneic hematopoietic stem cell transplantation (AlloHSCT). The main goal of the study was the identification of prognostic factors for 4‐month aspergillosis free survival (AFS) and overall survival (OS). IA was identified as the main cause of death in 27/49 recipients of an AlloHSCT (55%) and 28/81 nontransplanted patients (35%). Diagnosis of IA at or before 2000 had a negative impact in both 4‐month AFS and 4‐month OS in the entire group. In multivariate analysis performed separately for nontransplanted and allo‐HSCT patients, five variables (excluding the year of diagnosis) decreased 4‐month AFS: (i) impairment of one organ function (OF), (ii) impairment of two or more OFs (two points), (iii) disseminated IA, (iv) neutropenia lasting more than 10 days (non‐AlloHSCT group only) or monocytopenia (<0.1 × 109/l) [AlloHSCT group only], and (v) high‐dose steroids (non‐AlloHSCT group only) or an alternative donor (AlloHSCT group only). According to the number of adverse risk factors, three prognostic subgroups were defined in non‐transplanted and alloHSCT patients with good (97% and 78% AFS), intermediate (73% and 32% AFS) and poor prognosis (20% and 11% AFS) of IA [P < 0.01]. In addition, we validated the French and Seattle prognostic indexes for allo‐HSCT recipients and the Strasbourg model for all hematological patients with IA. Am. J. Hematol., 2009.

Human metapneumovirus infection in hematopoietic stem cell transplant recipients: high-resolution computed tomography findings.

Purpose: To review the high-resolution computed tomography (CT) findings in hematopoietic stem cell transplant (HCT) recipients who had proven human metapneumovirus (HMPV) pneumonia. Materials and Methods: The study included 5 HCT recipients who had proven HMPV pneumonia. The patients included 4 men and 1 woman ranging in age from 23 to 58 years (mean age = 42 years). The CT scans were assessed for the presence, appearance, size, and distribution of parenchymal abnormalities. Results: Human metapneumovirus was isolated in all 5 patients in this series. None of these patients had any other infectious organism identified in cultures or bronchoalveolar lavage. The predominant CT findings were bilateral abnormalities in all patients, consisting primarily of a mixture of patterns, including, most commonly, ground-glass attenuation and nodular opacities. Areas of ground-glass opacification had no zonal predominance and were bilateral, asymmetric, and patchily distributed. Multiple nodules were identified in 4 (80%) of 5 patients. Nodules were multiple; less than 5 nodules were identified in 1 case, and 5 to 10 nodules were identified in 3 cases. All nodules in all cases were less than 10 mm in diameter. Areas of air-space consolidation were identified in 2 (40%) patients. All patients were available for follow-up; lesions improved in 4 patients. Conclusion: The thin-section CT manifestations of HMPV pneumonia usually consist of a mixture of patterns, including, most commonly, ground-glass attenuation and nodular opacities.

Protective Effects of Ticagrelor on Myocardial Injury After Infarction

Background: The P2Y12 receptor antagonist ticagrelor has been shown to be clinically superior to clopidogrel. Although the underlying mechanisms remain elusive, ticagrelor may exert off-target effects through adenosine-related mechanisms. We aimed to investigate whether ticagrelor reduces myocardial injury to a greater extent than clopidogrel after myocardial infarction (MI) at a similar level of platelet inhibition and to determine the underlying mechanisms. Methods: Pigs received the following before MI induction: (1) placebo-control; (2) a loading dose of clopidogrel (600 mg); (3) a loading dose of ticagrelor (180 mg); or (4) a loading dose of ticagrelor followed by an adenosine A1/A2-receptor antagonist [8-(p-sulfophenyl)theophylline, 4 mg/kg intravenous] to determine the potential contribution of adenosine in ticagrelor-related cardioprotection. Animals received the corresponding maintenance doses of the antiplatelet agents during the following 24 hours and underwent 3T-cardiac MRI analysis. Platelet inhibition was monitored by ADP-induced platelet aggregation. In the myocardium, we assessed the expression and activation of proteins known to modulate edema formation, including aquaporin-4 and AMP-activated protein kinase and its downstream effectors CD36 and endothelial nitric oxide synthase and cyclooxygenase-2 activity. Results: Clopidogrel and ticagrelor exerted a high and consistent antiplatelet effect (68.2% and 62.2% of platelet inhibition, respectively, on challenge with 20 &mgr;mol/L ADP) that persisted up to 24 hours post-MI (P<0.05). All groups showed comparable myocardial area-at-risk and cardiac worsening after MI induction. 3T-Cardiac MRI analysis revealed that clopidogrel- and ticagrelor-treated animals had a significantly smaller extent of MI than placebo-control animals (15.7 g left ventricle and 12.0 g left ventricle versus 22.8 g left ventricle, respectively). Yet, ticagrelor reduced infarct size to a significantly greater extent than clopidogrel (further 23.5% reduction; P=0.0026), an effect supported by troponin-I assessment and histopathologic analysis (P=0.0021). Furthermore, in comparison with clopidogrel, ticagrelor significantly diminished myocardial edema by 24.5% (P=0.004), which correlated with infarct mass (r=0.73; P<0.001). 8-(p-Sulfophenyl)theophylline administration abolished the cardioprotective effects of ticagrelor over clopidogrel. At a molecular level, aquaporin-4 expression decreased and the expression and activation of AMP-activated protein kinase signaling and cyclooxygenase-2 increased in the ischemic myocardium of ticagrelor- versus clopidogrel-treated animals (P<0.05). These protein changes were not observed in those animals administered the adenosine receptor blocker 8-(p-sulfophenyl)theophylline. Conclusions: Ticagrelor, beyond its antiplatelet efficacy, exerts cardioprotective effects by reducing necrotic injury and edema formation via adenosine-dependent mechanisms.

Correlation between high-resolution computed tomography and galactomannan antigenemia in adult hematologic patients at risk for invasive aspergillosis

OBJECTIVES To analyse the predominant radiological pattern of pulmonary lesions in adult hematologic patients at risk for invasive aspergillosis (IA) together with the results of serial serum Aspergillus galactomannan antigen testing (GM). MATERIAL AND METHODS In a prospective study for patients at high risk of aspergillus pulmonary infection, serum GM were performed 2-3 times per week during the periods of high risk for IA and high-resolution CT (HRCT) was performed in case of abnormal chest X-ray (CXR) and/or persistent fever after 5 days of antibiotic treatment. Changes on HRCT scan were classified as airway IA and angioinvasive IA. IA was classified as proven or probable in accordance with the definitions stated by the European Organization for Research and Treatment of Cancer/Mycosis Study Group (EORTC-MS). Positive GM testing was not considered as microbiological criterion. RESULTS 38 hematological patients were diagnosed of probable (n=28) or proven (n=10) IA. 55% patients had a neutrophil count less than 500 mm(-3) (n=21), and 37% patients > or =2 risk factors for IA. All probable IA were diagnosed by bronchoalveolar lavage (BAL). Proven IA was reached by positive histopathologic and culture results of samples obtained by autopsy (n=4), percutaneous (n=3) or transbronchial biopsy (n=3). 18 patients had airway IA, and 60% had a GM level > or =1.5. 20 patients were diagnosed of angioinvasive IA from which 80% had a GM level > or =1.5. CONCLUSION Serum GM levels may be lower in patients with airway IA than in those with an angioinvasive form. HRCT and serum GM are complementary tests in the diagnosis of IA.

Air-leak syndromes in hematopoietic stem cell transplant recipients with chronic GVHD: high-resolution CT findings.

Objectives The purpose of this study was to determine the incidence and the high-resolution computed tomography findings of air-leak syndromes in a large group of hematopoietic stem cell (HSC) transplant recipients with proved chronic graft versus host disease (cGVHD). Materials and Methods High-resolution computed tomography scans of 9 allogeneic HSC transplant recipients (8 men, 1 woman; 19 to 45 years of age; median 28 y), with a proven diagnosis of cGVHD-related bronchiolitis obliterans syndrome (BOS) were reviewed for the presence, appearance, and distribution of abnormalities. Results Nine patients with cGVHD developed 10 episodes of spontaneous air-leak syndromes secondary to cGVHD-related BOS during the study period analyzed; for a 2-year estimated cumulative incidence of 2.1% (95% confidence interval 0.2% to 3.8%) its prevalence was 5.7% (95%CI: 2.6% to 10.5%). All cases were allogeneic HSC transplant recipients with cGVHD who acquired new respiratory symptoms and/or radiologic abnormalities. Pneumomediastinum and pneumothorax were present in 6 patients. Subcutaneous emphysema was identified in 3 patients and pulmonary interstitial emphysema in 2 patients. A combination of different air-leak syndromes was observed in 6 patients. Conclusion Air-leak syndromes represent an uncommon late complication in HSC transplant recipients with cGVHD-related BOS.

Correlation between myocardial fibrosis and the occurrence of atrial fibrillation in hypertrophic cardiomyopathy: a cardiac magnetic resonance imaging study.

Cardiac magnetic resonance imaging (CMR) in hypertrophic cardiomyopathy (HCM) often shows delayed contrast enhancement (DE) representing regions of focal myocardial fibrosis. Atrial fibrillation (AF) is a commonly reported complication of HCM. We determined the relationship between the presence of left ventricular myocardial fibrosis (LVMF) detected by DE-CMR and the occurrence AF in a series of patients with HCM. 67 patients with HCM (47 males; mean age 50.1+/-18.5 years) were studied by CMR measuring mass of LVMF, left ventricular mass, volume and function, and left atrial (LA) area. AF was present in 17 (25%) patients. LVMF was observed in 57% of patients. AF was significantly more frequent in patients who also showed LVMF, compared with the group without LVMF (42.1% vs. 3.4%, respectively; p<0.0001). LA size was larger in patients showing DE (LA area: 37.4+/-11.1 vs. 25.9+/-6.8 cm(2); respectively, p=0.0001). AF in HCM is related with myocardial fibrosis detected by DE-CMR and dilatation of the LA. This fact adds to the proven adverse prognostic value of myocardial fibrosis in HCM, thus, reinforcing the usefulness of this technique in the assessment of these patients.

16-MDCT and MR Angiography of Accessory Diaphragm

1All authors: Department of Radiology, Hospital de Sant Pau, Universidad Autonoma de Barcelona, S. Antoni M Cret 167, 08025 Barcelona, Spain. Address correspondence to A. Hildago (jhidalgop@hsp.santpau.es). e describe an unusual accessory diaphragm, also known as diaphragmatic duplication, identified on chest radiography, contrast-enhanced MDCT, and MR angiography (MRA). In this case, the malformation was associated with a unilateral single pulmonary vein. There are few reported cases of this rare pulmonary malformation, which is sometimes confused with lobar atelectasis and residual changes secondary to pulmonary infections. However, the specific radiologic findings allow a correct diagnosis.

Inferior type sinus venosus atrial septal defect: MR findings.

Atrial septal defects can occur at various levels of the interatrial septum. Sinus venosus atrial septal defect (SVASD) results from abnormal resorption of the embryologic sinus venosus, and may be of the superior or inferior type. In this paper, we describe a 46-year-old man with inferior-type SVASD who presented with arrhythmias and dyspnea. Cardiac magnetic resonance and cardiac catheterization were useful in evaluating the anatomic/functional characteristics of inferior-type SVASD and distinguishing it from unroofed coronary sinus.