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Left atrial volumetry from routine diagnostic work up prior to pulmonary vein ablation is a good predictor of freedom from atrial fibrillation

AIMSnThis study aimed to identify whether left atrial (LA) volume assessed by multidetector computed tomography (MDCT) is related to the long-term success of pulmonary vein ablation (PVA). MDCT is used to guide PVA for the treatment of atrial fibrillation (AF). MDCT permits accurate sizing of LA dimensions.nnnMETHODS AND RESULTSnWe analysed data from 368 ablation procedures of 279 consecutive patients referred for PVA due to drug-refractory symptomatic AF (age 62 ± 10; 58% men; 71% paroxysmal AF). Prior to the procedure, all patients underwent ECG-gated 64-MDCT scan for assessment of LA and PV anatomy, LA thrombus evaluation, LA volume estimation, and electroanatomical mapping integration. Within a mean follow-up of 356 ± 128 days, 64% of the patients maintained sinus rhythm after the initial ablation, and 84% when including repeat PVA. LA diameter (P = 0.004), LA volume (P = 0.002), and type of AF (P = 0.001) were independent predictors of AF recurrence in univariate analysis. There was a relatively low correlation between the echocardiographic LA diameter and LA volume from MDCT (P = 0.01, r = 0.5). In multivariate analysis, paroxysmal AF (P < 0.006) and LA volume below the median value of 106 mL (P = 0.042) were significantly associated with the success of PVA, whereas LA diameter was not (P = 0.245). Analysing receiver-operator characteristics, the area under the curve for LA volume was 0.73 (P = 0.001) compared with 0.60 (P = 0.09) for LA diameter from echocardiography.nnnCONCLUSIONnLA volume assessed by MDCT is a better predictor of AF recurrence after PVA than echocardiograpic LA diameter and can be derived from the pre-procedural imaging data set.

Frequency-Domain Optical Tomographic Imaging of Arthritic Finger Joints

We are presenting data from the largest clinical trial on optical tomographic imaging of finger joints to date. Overall we evaluated 99 fingers of patients affected by rheumatoid arthritis (RA) and 120 fingers from healthy volunteers. Using frequency-domain imaging techniques we show that sensitivities and specificities of 0.85 and higher can be achieved in detecting RA. This is accomplished by deriving multiple optical parameters from the optical tomographic images and combining them for the statistical analysis. Parameters derived from the scattering coefficient perform slightly better than absorption derived parameters. Furthermore we found that data obtained at 600 MHz leads to better classification results than data obtained at 0 or 300 MHz.

Current perspective of multidetector computed tomography (MDCT) in patients after midface and craniofacial trauma

PURPOSEnThe purpose of the study was to determine the prevalence of fractures and incidental findings (IF) with emphasis on clinical significance.nnnMATERIALS AND METHODSnA total of 784 patients were evaluated by computed tomography. Fractures and IF were registered and classified as significant if they were recommended for additional diagnostics or therapy.nnnRESULTSnFour hundred seventy of 784 patients (60%) sustained a fracture. Significant fractures were found in 694/1213 fractures (57%); nonsignificant fractures were found in 519/1213 (43%) fractures. A total of 972 IF were observed in 464/784 (59%) patients. Significant findings were found in 358/972 findings (37%). There were 1.5 fractures and 1.2 IF per patient.nnnCONCLUSIONnThere is a high prevalence of significant fractures (57%) and IF (37%).

Current role of cardiac and extra-cardiac pathologies in clinically indicated cardiac computed tomography with emphasis on status before pulmonary vein isolation.

PURPOSEnThe aim of this study was to assess the incidence of cardiac and significant extra-cardiac findings in clinical computed tomography of the heart in patients with atrial fibrillation before pulmonary vein isolation (PVI).nnnMATERIALS AND METHODSn224 patients (64u200a±u200a10 years; male 63u200a%) with atrial fibrillation were examined by cardiac 64-slice multidetector CT before PVI. Extra-cardiac findings were classified as significant if they were recommended to additional diagnostics or therapy, and otherwise as non-significant. Additionally, cardiac findings were documented in detail.nnnRESULTSnA total of 724 cardiac findings were identified in 203 patients (91u200a% of patients). Additionally, a total of 619 extra-cardiac findings were identified in 179 patients (80u200a% of patients). Among these extra-cardiac findings 196 (32u200a%) were significant, and 423 (68u200a%) were non-significant. In 2 patients (1u200a%) a previously unknown malignancy was detected (esophageal cancer and lung cancer, local stage, no metastasis). 203 additional imaging diagnostics followed to clarify the significant findings (124 additional CT, costs 38u200a314.69 US dollars). Overall, there were 3.2 cardiac and 2.8 extra-cardiac findings per patient. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (pu200a<0.05).nnnCONCLUSIONnCardiac CT scans before PVI should be screened for extracardiac incidental findings that could have important clinical implications for each patient.

Intrathoracic fire during preparation of the left internal thoracic artery for coronary artery bypass grafting

A surgical fire is a serious complication not previously described in the literature with regard to the thoracic cavity. We report a case in which an intrathoracic fire developed following an air leak combined with high pressure oxygen ventilation in a patient with severe chronic obstructive pulmonary disease. The patient presented to our institution with diffuse coronary artery disease and angina pectoris. He was treated with coronary artery bypass graft surgery, including left internal thoracic artery harvesting. Additionally to this rare presentation of an intrathoracic fire, a brief review of surgical fires is included to this paper.

Split-Bolus Single-Phase Cardiac Multidetector Computed Tomography for Reliable Detection of Left Atrial Thrombus: Comparison to Transesophageal Echocardiography

PURPOSEnEvaluation of a new cardiac MDCT protocol using a split-bolus contrast injection protocol and single MDCT scan for reliable diagnosis of LA/LAA thrombi in comparison to TEE, optimizing radiation exposure and use of contrast agent.nnnMATERIALS AND METHODSnA total of 182 consecutive patients with drug refractory AF scheduled for PVI (62.6u200a% male, mean age: 64.1u200a±u200a10.2 years) underwent routine diagnostic work including TEE and cardiac MDCT for the evaluation of LA/LAA anatomy and thrombus formation between November 2010 and March 2012. Contrast media injection was split into a pre-bolus of 30u200aml and main bolus of 70u200aml iodinated contrast agent separated by a short time delay.nnnRESULTSnIn this study, split-bolus cardiac MDCT identified 14 of 182 patients with filling defects of the LA/LAA. In all of these 14 patients, abnormalities were found in TEE. All 5 of the 14 patients with thrombus formation in cardiac MDCT were confirmed by TEE.nnnCONCLUSIONnMDCT was 100u200a% accurate for thrombus, with strong but not perfect overall results for SEC equivalent on MDCT.nnnKEY POINTSn•u2007Patients with no filling defect or thrombus in MDCT in the LA/LAA region are unlikely to have thrombus and may undergo PVI without TEE.•u2007Here, the role of an additional TEE in pre-procedural management prior to PVI in patients with AF has to be redefined.•u2007Using a split-bolus injection protocol increases the diagnostic accuracy of thrombus in the LA/LAA region.

Computer-aided classification of rheumatoid arthritis in finger joints using frequency domain optical tomography

Novel methods that can help in the diagnosis and monitoring of joint disease are essential for efficient use of novel arthritis therapies that are currently emerging. Building on previous studies that involved continuous wave imaging systems we present here first clinical data obtained with a new frequency-domain imaging system. Three-dimensional tomographic data sets of absorption and scattering coefficients were generated for 107 fingers. The data were analyzed using ANOVA, MANOVA, Discriminant Analysis DA, and a machine-learning algorithm that is based on self-organizing mapping (SOM) for clustering data in 2-dimensional parameter spaces. Overall we found that the SOM algorithm outperforms the more traditional analysis methods in terms of correctly classifying finger joints. Using SOM, healthy and affected joints can now be separated with a sensitivity of 0.97 and specificity of 0.91. Furthermore, preliminary results suggest that if a combination of multiple image properties is used, statistical significant differences can be found between RA-affected finger joints that show different clinical features (e.g. effusion, synovitis or erosion).

Comparison of Classification Methods for Detection of Rheumatoid Arthritis with Optical Tomography

Using optical tomographic data from fingers affected by RA we compare the performance of 3 different classification methods. Linear discriminant and quadratic discriminant analysis methods yield high sensitivities while support-vector machine-based methods yield high specificities.

Prevalence and clinical relevance of extra-cardiac findings at cardiac magnetic resonance imaging

Background The aim of this study was to assess the incidence of extra-cardiac findings in patients undergoing clinical cardiac magnetic resonance imaging (CMRI) of the heart including surrounding structures and to determine the influence of those findings on patient’s management. Methods N=854 patient studies (median age 58 ± 12 years, male 63%) were included and examined by 1.5 Tesla (T) MR to primarily analyze the cardiac anatomy and secondly the surrounding structures. Extra-cardiac findings were classified as significant (Group A) if they were recommended to additional diagnostics or therapeutical interventions and as non-significant if there was no influence on patient’s management (Group B). Results 631 patient studies were free of any kind of extra-cardiac pathologies. In the remaining cases, 286 extra-cardiac findings were examined. There were ~0.33 extracardiac findings per patient. 49 were defined as significant (Group A) and 237 as nonsignificant findings (Group B). The most common Group A findings were suspicious pulmonary nodules or masses > 4 mm diameter (n=14) and aortic aneurysms (n=5). In Group B, most of the findings were hepatic cysts or hemangiomas (n=50), followed by renal cysts (n=47). 8 malignancies were certainly observed. The most frequent indication for CMRI was evaluation of cardiac stress ischemia (n=501, 59%). Conclusions Extra-cardiac findings in clinical CMRI are common in patients referred to CMRI (26%). Radiologists and cardiologists have to be aware of relevant extra-cardiac findings which might require additional diagnostics or treatment. There is an importance of paying appropriate attention to structures outside of the heart.

Prognostischer Stellenwert der links-atrialen Dimensionen vor Pulmonalvenenisolation bei Patienten mit Vorhofflimmern: Vergleich zwischen Echokardiografie & Multidetektor-Computertomografie (MDCT)

Fragestellung: Die MDCT ermoglicht eine exakte Darstellung der Anatomie des linken Vorhofs (LA). Die 3D-Schnittbilddiagnostik dient der Ablationsplanung und dem elektroanatomischen Mapping (EAM). Ziel dieser Studie war es den prognostischen Stellenwert der links-atrialen Dimensionen aus dem MDCT und der Echokardiografie (Echo) in Bezug auf den Therapieerfolg der Pulmonalvenenisolation bei Patienten mit Vorhofflimmern (VHF) zu vergleichen. Methoden: 102 Patienten mit antiarrhythmika-refraktarem, symptomatischen Vorhofflimmern (VHF) erhielten eine zirkumferentielle PVA. Alle Patienten erhielten vor Ablation ein EKG-getriggertes 64-MDCT des Herzen und eine Echokardiografie zur Bestimmung des LA-Diameters. Die praprozedural erhobenen LA-Durchmesser und Volumina-Werte wurden einer uni- und multivariaten Analyse zugefuhrt. Kaplan-Meier-Kurven, ROC-Analysen und AUC wurden erstellt. Ergebnisse: 65% der Patienten blieben im Sinusrythmus; 83% nach erneuter PVA. In der univariaten Analyse stellten sich der LA-Durchmesser >42mm (p0,02), das LA-Volumen >110ml (p0,03) und die Art des VHF (nicht-paroxysmal p0,05) als prognostische Faktoren heraus. In der multivariaten Analyse waren ein LA-Volumen von <110ml (p0,04) und paroxysmales Vorhofflimmern (p<0,01) signifikante Pradiktoren fur den Therapieerfolg, nicht jedoch der LA-Durchmesser. In der ROC-Analyse fur den prognositschen Stellenwert war das LA-Volumen im MDCT (AUC 0,70; p0,016) dem LA-Durchmesser im Echo (AUC 0,60; p0,11) uberlegen. In der Kaplan-Meier-Analyse stellt sich ein signifikanter Unterschied in der Rezidivwahrscheinlichkeit uber bzw. unter einem mittlerem Volumen von 109ml dar (p=0,03). Schlussfolgerung: Die MDCT ist eine wichtige und Untersucher-unabhangige Methode zur Planung der PVA und das LA-Volumen ein starkerer signifikanter prognostischer Faktor fur den Therapieerfolg als der LA-Durchmesser im Echo. Die Quantifizierung des LA-Volumens kann problemlos in die praprozedurale Diagnostik eingebunden werden und sollte im Rahmen der Routine vor PVA erhoben werden. Referenzen: Niinuma H, George RT, Arbab-Zadeh A, Lima JA, Henrikson CA. Imaging of pulmonary veins during catheter ablation for atrial fibrillation: the role of multi-slice computed tomography. Europace 2008;10 Suppl 3:iii14–21. Kistler PM, Rajappan K, Jahngir M, Earley MJ, Harris S, Abrams D, Gupta D, Liew R, Ellis S, Sporton SC, Schilling RJ. The impact of CT image integration into an electroanatomic mapping system on clinical outcomes of catheter ablation of atrial fibrillation. J Cardiovasc Electrophysiol. 2006;17:1093–101. Dorenkamp M, Sohns C, Vollmann D, Luthje L, Seegers J, Wachter R, Puls M, Staab W, Lotz J, Zabel M. Detection of left atrial thrombus during routine diagnostic work-up prior to pulmonary vein isolation for atrial fibrillation: Role of transesophageal echocardiography and multidetector computed tomography. Int J Cardiol. 2011 Jul 15. [Epub ahead of print].