Accuracy of computed tomography in detection of great vessel stenosis or hypoplasia before superior bidirectional cavopulmonary connection: Comparison with cardiac catheterization and surgical findings.

BACKGROUND: Cardiac catheterization is the gold-standard modality for investigation of cardiovascular morphology before bidirectional cavopulmonary connection, but requires general anaesthesia and is associated with procedural risk. AIMS: To assess the diagnostic accuracy and safety of computed tomography in diagnosing great vessel stenosis/hypoplasia compared with cardiac catheterization and surgical findings. METHODS: Twenty-seven patients (10 after Norwood stage I) underwent computed tomography before surgery between January 2010 and June 2016; 16 of these patients also underwent cardiac catheterization. Proximal and distal pulmonary artery, aortic isthmus and descending aorta measurements, radiation dose and complications were compared via Bland-Altman analyses and correlation coefficients. RESULTS: The accuracy of computed tomography in detecting stenosis/hypoplasia of either pulmonary artery was 96.1% compared with surgical findings. For absolute vessel measurements and Z-scores, there was high correlation between computed tomography and angiography at catheterization (r=0.98 for both) and a low mean bias (0.71mm and 0.48; respectively). The magnitude of intertechnique differences observed for individual patients was low (95% of the values ranged between -0.9 and 2.3mm and between -0.7 and 1.7, respectively). Four patients (25%) experienced minor complications from cardiac catheterization, whereas there were no complications from computed tomography. Patients tended to receive a higher radiation dose with cardiac catheterization than with computed tomography, even after exclusion of interventional catheterization procedures (median 2.5 mSv [interquartile range 1.3 to 3.4 mSv] versus median 1.3 mSv [interquartile range 0.9 to 2.6 mSv], respectively; P=0.13). All computed tomography scans were performed without sedation. CONCLUSIONS: Computed tomography may replace cardiac catheterization in identification of great vessel stenosis/hypoplasia before bidirectional cavopulmonary connection when no intervention before surgery is required. Computed tomography carries lower morbidity, can be performed without sedation and may be associated with less radiation.

High-pitch versus conventional cardiovascular CT in patients being assessed for transcatheter aortic valve implantation: a real-world appraisal.

OBJECTIVE: High-pitch protocols are increasingly used in cardiovascular CT assessment for transcatheter aortic valve implantation (TAVI), but the impact on diagnostic image quality is not known. METHODS: We reviewed 95 consecutive TAVI studies: 44 (46%) high-pitch and 51 (54%) standard-pitch. Single high-pitch scans were performed regardless of heart rate. For standard-pitch acquisitions, a separate CT-aortogram and CT-coronary angiogram were performed with prospective gating, unless heart rate was ≥70 beats/min, when retrospective gating was used. The aortic root and coronary arteries were assessed for artefact (significant artefact=1; artefact not limiting diagnosis=2; no artefact=3). Aortic scans were considered diagnostic if the score was >1; the coronaries, if all three epicardial arteries scored >1. RESULTS: There was no significant difference in diagnostic image quality for either the aorta (artefact-free high-pitch: 31 (73%) scans vs standard-pitch: 40 (79%), p=0.340) or the coronary tree as a whole (10 (23%) vs 15 (29%), p=0.493). However, proximal coronary arteries were less well visualised using high-pitch acquisitions (16 (36%) vs 30 (59%), p=0.04). The median (IQR) radiation dose was significantly lower in the high-pitch cohort (dose-length product: 347 (318-476) vs 1227 (1150-1474) mGy cm, respectively, p<0.001), and the protocol required almost half the amount of contrast. CONCLUSIONS: The high-pitch protocol significantly reduces radiation and contrast doses and is non-inferior to standard-pitch acquisitions for aortic assessment. For aortic root assessment, the high-pitch protocol is recommended. However, if coronary assessment is critical, this should be followed by a conventional standard-pitch, low-dose, prospectively gated CT-coronary angiogram if the high-pitch scan is non-diagnostic.

Variants of the scimitar syndrome.

UNLABELLED: Introduction The scimitar syndrome comprises hypoplastic right pulmonary artery and lung, anomalous right pulmonary venous drainage to the inferior caval vein, aortopulmonary collateral(s) to the right lung, and bronchial anomalies. Aim The aim of this study was to describe the morphological and clinical spectrum of variants from the classical scimitar syndrome in a single institution over 22 years. RESULTS: In total, 10 patients were recognised. The most consistent feature was an aortopulmonary collateral to the affected lung (90%), but there was considerable variation in the site and course of pulmonary venous drainage. This was normal in 3 (one with meandering course), anomalous right to superior caval vein in 1, to the superior caval vein and inferior caval vein in 2, and to the superior caval vein and the left atrium in 1; one patient had a right pulmonary (scimitar) vein occluded at the insertion into the inferior caval vein but connected to the right upper pulmonary vein via a fistula. There were two left-sided variants, one with anomalous left drainage to the coronary sinus and a second to the innominate vein. Among all, three patients had an antenatal diagnosis and seven presented between 11 and 312 months of age; 90% of the patients were symptomatic at first assessment. All the patients underwent cardiac catheterisation; collateral embolisation was performed in 50% of the patients. Surgical repair of the anomalous vein was carried out in two patients, one patient had a right pneumonectomy, and one patient was lost to follow-up. There was no mortality reported in the remainder of patients during the study period. CONCLUSION: The heterogeneity of this small series confirms the consistent occurrence of an anomalous arterial supply to the affected lung but considerable variation in pulmonary venous drainage.

A low-dose, dual-phase cardiovascular CT protocol to assess left atrial appendage anatomy and exclude thrombus prior to left atrial intervention.

Assessment of the left atrial appendage (LAA) for thrombus and anatomy is important prior to atrial fibrillation (AF) ablation and LAA exclusion. The use of cardiovascular CT (CCT) to detect LAA thrombus has been limited by the high incidence of pseudothrombus on single-pass studies. We evaluated the diagnostic accuracy of a two-phase protocol incorporating a limited low-dose delayed contrast-enhanced examination of the LAA, compared with a single-pass study for LAA morphological assessment, and transesophageal echocardiography (TEE) for the exclusion of thrombus. Consecutive patients (n = 122) undergoing left atrial interventions for AF were assessed. All had a two-phase CCT protocol (first-past scan plus a limited, 60-s delayed scan of the LAA) and TEE. Sensitivity, specificity, diagnostic accuracy, positive (PPV) and negative predictive values (NPV) were calculated for the detection of true thrombus on first-pass and delayed scans, using TEE as the gold standard. Overall, 20/122 (16.4 %) patients had filling defects on the first-pass study. All affected the full delineation of the LAA morphology; 17/20 (85 %) were confirmed as pseudo-filling defects. Three (15 %) were seen on late-pass and confirmed as true thrombi on TEE; a significant improvement in diagnostic performance relative to a single-pass scan (McNemar Chi-square 17, p < 0.001). The sensitivity, specificity, diagnostic accuracy, PPV and NPV was 100, 85.7, 86.1, 15.0 and 100 % respectively for first-pass scans, and 100 % for all parameters for the delayed scans. The median (range) additional radiation dose for the delayed scan was 0.4 (0.2-0.6) mSv. A low-dose delayed scan significantly improves the identification of true LAA anatomy and thrombus in patients undergoing LA intervention.

Bronchoscopic lung volume reduction with endobronchial valves for patients with heterogeneous emphysema and intact interlobar fissures (the BeLieVeR-HIFi study): a randomised controlled trial.

BACKGROUND: Lung volume reduction surgery improves survival in selected patients with emphysema, and has generated interest in bronchoscopic approaches that might achieve the same effect with less morbidity and mortality. Previous trials with endobronchial valves have yielded modest group benefits because when collateral ventilation is present it prevents lobar atelectasis. METHODS: We did a single-centre, double-blind sham-controlled trial in patients with both heterogeneous emphysema and a target lobe with intact interlobar fissures on CT of the thorax. We enrolled stable outpatients with chronic obstructive pulmonary disease who had a forced expiratory volume in 1 s (FEV1) of less than 50% predicted, significant hyperinflation (total lung capacity >100% and residual volume >150%), a restricted exercise capacity (6 min walking distance <450 m), and substantial breathlessness (MRC dyspnoea score ≥3). Participants were randomised (1:1) by computer-generated sequence to receive either valves placed to achieve unilateral lobar occlusion (bronchoscopic lung volume reduction) or a bronchoscopy with sham valve placement (control). Patients and researchers were masked to treatment allocation. The study was powered to detect a 15% improvement in the primary endpoint, the FEV1 3 months after the procedure. Analysis was on an intention-to-treat basis. The trial is registered at controlled-trials.com, ISRCTN04761234. FINDINGS: 50 patients (62% male, FEV1 [% predicted] mean 31·7% [SD 10·2]) were enrolled to receive valves (n=25) or sham valve placement (control, n=25) between March 1, 2012, and Sept 30, 2013. In the bronchoscopic lung volume reduction group, FEV1 increased by a median 8·77% (IQR 2·27-35·85) versus 2·88% (0-8·51) in the control group (Mann-Whitney p=0·0326). There were two deaths in the bronchoscopic lung volume reduction group and one control patient was unable to attend for follow-up assessment because of a prolonged pneumothorax. INTERPRETATION: Unilateral lobar occlusion with endobronchial valves in patients with heterogeneous emphysema and intact interlobar fissures produces significant improvements in lung function. There is a risk of significant complications and further trials are needed that compare valve placement with lung volume reduction surgery. FUNDING: Efficacy and Mechanism Evaluation Programme, funded by the Medical Research Council (MRC) and managed by the National Institute for Health Research (NIHR) on behalf of the MRC-NIHR partnership.

Clinical and economic consequences of non-cardiac incidental findings detected on cardiovascular computed tomography performed prior to transcatheter aortic valve implantation (TAVI).

Transcatheter aortic valve implantation (TAVI) is an effective treatment option for patients with severe degenerative aortic valve stenosis who are high risk for conventional surgery. Computed tomography (CT) performed prior to TAVI can detect pathologies that could influence outcomes following the procedure, however the incidence, cost, and clinical impact of incidental findings has not previously been investigated. 279 patients underwent CT; 188 subsequently had TAVI and 91 were declined. Incidental findings were classified as clinically significant (requiring treatment), indeterminate (requiring further assessment), or clinically insignificant. The primary outcome measure was all-cause mortality up to 3 years. Costs incurred by additional investigations resultant to incidental findings were estimated using the UK Department of Health Payment Tariff. Incidental findings were common in both the TAVI and medical therapy cohorts (54.8 vs. 70.3%; P = 0.014). Subsequently, 45 extra investigations were recommended for the TAVI cohort, at an overall average cost of £32.69 per TAVI patient. In a univariate model, survival was significantly associated with the presence of a clinically significant or indeterminate finding (HR 1.61; P = 0.021). However, on multivariate analysis outcomes after TAVI were not influenced by any category of incidental finding. Incidental findings are common on CT scans performed prior to TAVI. However, the total cost involved in investigating these findings is low, and incidental findings do not independently identify patients with poorer outcomes after TAVI. The discovery of an incidental finding on CT should not necessarily influence or delay the decision to perform TAVI.

Pulmonary atresia with double ductus arteriosus.

We present the case of a neonate with pulmonary atresia and persistent bilateral patent ductus arteriosus imaged by gated multidetector CT. Traditionally, these patients have been assessed preoperatively with invasive angiocardiography or with cardiovascular magnetic resonance under sedation. Our case illustrates that contemporary cardiovascular CT techniques can now be used for preoperative evaluation with minimal radiation penalty, obviating the risks of sedation or cardiac catheterization.

Diagnosing rare cases of anomalous origin of the coronary arteries in tetralogy of Fallot using CT in an infant and an adult.

Major and minor coronary artery anomalies in tetralogy of Fallot is a well-described finding. The importance of determining the coronary distribution impacts upon the decision making for surgery and subsequent management. Traditionally, the coronary distribution is relied classically on echocardiography and cardiac catheterisation; however, they have well-known limitations. The use of CT as a first-line investigation modality for coronary artery distribution is discussed.

An unusual case of ventricular ectopy in a military pilot.

BACKGROUND: Congenital left ventricular diverticula are an uncommon cardiac malformation. Although they may be asymptomatic, their presence is important to note as they are associated with systemic embolization of mural thrombus, valvular regurgitation, heart failure, focal ventricular arrhythmias, and sudden death. CASE REPORT: We describe a case of an asymptomatic pilot with a significant burden of ventricular ectopy. The diagnosis of a large left ventricular diverticulum was made by cardiac CT and confirmed by cardiac magnetic resonance imaging. No specific treatment was warranted; however, regular on-going follow up was required. DISCUSSION: It is important to seek out a structural cause for frequent ventricular ectopy even in the absence of symptoms. Transthoracic echocardiography is not always able to delineate the entire left ventricular cavity and other imaging modalities such as ECG-gated cardiac CT or gated MRI may need to be used in conjunction to permit assessment for the presence of structural heart disease in the whole heart. Aircrew with a high burden of ectopy require regular follow-up for complications such as more malignant dysrhythmias or LV impairment. In some cases, pharmacological or even surgical treatment is warranted, which may have a significant bearing for the future licensing of aircrew.

Personalised external aortic root support (PEARS) in Marfan syndrome: analysis of 1-9†year outcomes by intention-to-treat in a cohort of the first 30 consecutive patients to receive a novel tissue and valve-conserving procedure, compared with the published results of aortic root replacement.

OBJECTIVE: Among people with Marfan syndrome who have a typical aortic root aneurysm, dissection is a characteristic cause of premature death. To pre-empt Type A dissection, composite root replacement with a mechanical valve became the standard of care in the 1980s and 1990s. This is being superseded by valve-sparing aortic root replacement to avoid lifelong anticoagulation. In 2004, a total root and valve-sparing procedure, personalised external aortic support, was introduced. We report here results among the first 30 recipients. METHODS: From cross-sectional digital images, the patient's own aorta is modelled by computer aided design and a replica is made in thermoplastic by rapid prototyping. On this, a personalised support of a macroporous polymer mesh is manufactured. The mesh is positioned around the aorta, closely applied from the aortoventricular junction to beyond the brachiocephalic artery. The operation is performed with a beating heart and usually without cardiopulmonary bypass. RESULTS: Between 2004 and 2011, 30 patients, median age 28 years (IQR 20-44) had this operation and have been prospectively followed for 1.4-8.8 years by February 2013. During a total of 133 patient-years there were no deaths or cerebrovascular, aortic or valve-related events. These early outcomes are better than published results for the more radical extirpative root replacement operations. CONCLUSIONS: The aortic valve, the root architecture, and the blood/endothelia interface are conserved. The perioperative burden is less and there has been freedom from aortic and valvular events. A prospective comparative study is planned.

Smoking-related emphysema is associated with idiopathic pulmonary fibrosis and rheumatoid lung.

BACKGROUND AND OBJECTIVE: A combined pulmonary fibrosis/emphysema syndrome has been proposed, but the basis for this syndrome is currently uncertain. The aim was to evaluate the prevalence of emphysema in idiopathic pulmonary fibrosis (IPF) and rheumatoid lung (rheumatoid arthritis-interstitial lung disease (RA-ILD)), and to compare the morphological features of lung fibrosis between smokers and non-smokers. METHODS: Using high-resolution computed tomography, the prevalence of emphysema and the pack-year smoking histories associated with emphysema were compared between current/ex-smokers with IPF (n = 186) or RA-ILD (n = 46), and non-chronic obstructive pulmonary disease (COPD) controls (n = 103) and COPD controls (n = 34). The coarseness of fibrosis was compared between smokers and non-smokers. RESULTS: Emphysema, present in 66/186 (35%) patients with IPF and 22/46 (48%) smokers with RA-ILD, was associated with lower pack-year smoking histories than in control groups (P < 0.05 for all comparisons). The presence of emphysema in IPF was positively linked to the pack-year smoking history (odds ratio 1.04, 95% confidence interval (CI) 1.02-1.06, P < 0.0005). In IPF, fibrosis was coarser in smokers than in non-smokers on univariate and multivariate analysis (P < 0.01 for all comparisons). In RA-ILD, fibrosis was coarser in patients with emphysema but did not differ significantly between smokers and non-smokers. CONCLUSIONS: In IPF and RA-ILD, a high prevalence of concurrent emphysema, in association with low pack-year smoking histories, and an association between coarser pulmonary fibrosis and a history of smoking in IPF together provide support for possible pathogenetic linkage to smoking in both diseases.

Catastrophic antiphospholipid syndrome in childhood: presentation with an inferior caval vein mass.

Venous thromboembolism remains one of the important causes of pulmonary hypertension in children. The causes of venous thromboembolism are varied and include antiphospholipid antibody syndrome (APS). Catastrophic APS (CAPS) is a severe variant of APS characterised by disseminated thrombosis and microangiopathy resulting in multiorgan failure. CAPS can occur independently (primary APS) but mainly occurs in association with systemic lupus erythematosus including the paediatric population. We report a young girl with primary CAPS who presented with pulmonary hypertension and an inferior vena cava mass masquerading as a tumour.

Large aneurysm of left coronary sinus of Valsalva presenting with effort-related ventricular fibrillation.

Sinus of Valsalva aneurysms are very rare and are often asymptomatic. Clinical manifestations depend on associated complications, most commonly rupture or dissection. We describe the unusual case of a 46-year old presenting with exercise-induced ventricular fibrillation due to extrinsic compression of the left coronary artery. We also describe the surgical correction by valve-sparing aortic root replacement.

Cardiothoracic ratio from postero-anterior chest radiographs: a simple, reproducible and independent marker of disease severity and outcome in adults with congenital heart disease.

OBJECTIVE: The wide spectrum of intracardiac anatomy and reparative surgery available for adults with congenital heart disease (ACHD) makes uniform measurement of cardiac size and disease severity challenging. The aim of this study was to assess the prognostic potential of cardiothoracic ratio, a simple marker of cardiomegaly, in a large cohort of ACHD. PATIENTS AND SETTING: Chest radiographs from 3033 ACHD patients attending our institution between 1998 and 2007 and 113 normal controls of similar age were analyzed blindly. DESIGN: Cardiothoracic ratio derived from plain postero-anterior chest radiographs, was compared between ACHD patients and controls, different diagnostic subgroups and different functional classes. Relationship between cardiothoracic ratio and survival was assessed using Cox regression. RESULTS: Average cardiothoracic ratio in ACHD was 52.0±7.6% (over 50% in 56.4%), significantly higher in all ACHD diagnostic subgroups compared to controls (42.3±4.0%, p<0.0001) and highest in the "complex" cardiac anatomy, Ebstein's anomaly and Eisenmenger subgroups. Cardiothoracic ratio related to functional class, but was high even in asymptomatic patients. During a median follow-up of 4.2years, 164 patients died. Patients with a cardiothoracic ratio >55% had an 8-fold increased risk of death compared to those in the lowest tertile (<48%). Even patients with mildly increased cardiothoracic ratio (48-55%) had an adjusted 3.6-fold increased mortality compared to the lowest tertile. CONCLUSIONS: Cardiothoracic ratio derived from postero-anterior chest radiographs is a simple, and reproducible marker, which relates to functional class and predicts independently mortality risk in ACHD patients.