Long Term outcomes of percutaneous atrial fibrillation ablation in patients with continuous monitoring.

INTRODUCTION: There is limited data using continuous monitoring to assess outcomes of atrial fibrillation (AF) ablation. This study assessed long-term outcomes of AF ablation in patients with implantable cardiac devices. METHODS: 207 patients (mean age 68.1 ± 9.5, 50.3% men) undergoing ablation for symptomatic AF were followed up for a mean period of 924.5 ± 636.7 days. Techniques included The Pulmonary Vein Ablation Catheter (PVAC) (59.4%), cryoablation (17.4%), point by point (14.0%) and The Novel Irrigated Multipolar Radiofrequency Ablation Catheter (nMARQ) (9.2%). RESULTS: 130 (62.8%) patients had paroxysmal AF (PAF) and 77 (37.2%) persistent AF. First ablation and repeat ablation reduced AF burden significantly (relative risk 0.91, [95% CI 0.89 to 0.94]; P <0.0001 and 0.90, [95% CI, 0.86-0.94]; P <0.0001). Median AF burden in PAF patients reduced from 1.05% (interquartile range [IQR], 0.1%-8.70%) to 0.10% ([IQR], 0%-2.28%) at one year and this was maintained out to four-years. Persistent AF burden reduced from 99.9% ([IQR], 51.53%-100%) to 0.30% ([IQR], 0%-77.25%) at one year increasing to 87.3% ([IQR], 4.25%-100%) after four years. If a second ablation was required, point-by-point ablation achieved greater reduction in AF burden (relative risk, 0.77 [95% CI, 0.65-0.91]; P <0.01). CONCLUSION: Ablation reduces AF burden both acutely and in the long-term. If a second ablation was required the point-by-point technique achieved greater reductions in AF burden than "single-shot" technologies. Persistent AF burden increased to near pre ablation levels by year 4 suggesting a different mechanism from PAF patients where this increase did not occur.

Catheter ablation vs. thoracoscopic surgical ablation in long-standing persistent atrial fibrillation: CASA-AF randomized controlled trial.

AIMS: Long-standing persistent atrial fibrillation (LSPAF) is challenging to treat with suboptimal catheter ablation (CA) outcomes. Thoracoscopic surgical ablation (SA) has shown promising efficacy in atrial fibrillation (AF). This multicentre randomized controlled trial tested whether SA was superior to CA as the first interventional strategy in de novo LSPAF. METHODS AND RESULTS: We randomized 120 LSPAF patients to SA or CA. All patients underwent predetermined lesion sets and implantable loop recorder insertion. Primary outcome was single procedure freedom from AF/atrial tachycardia (AT) ≥30 s without anti-arrhythmic drugs at 12 months. Secondary outcomes included clinical success (≥75% reduction in AF/AT burden); procedure-related serious adverse events; changes in patients' symptoms and quality-of-life scores; and cost-effectiveness. At 12 months, freedom from AF/AT was recorded in 26% (14/54) of patients in SA vs. 28% (17/60) in the CA group [OR 1.128, 95% CI (0.46-2.83), P = 0.83]. Reduction in AF/AT burden ≥75% was recorded in 67% (36/54) vs. 77% (46/60) [OR 1.13, 95% CI (0.67-4.08), P = 0.3] in SA and CA groups, respectively. Procedure-related serious adverse events within 30 days of intervention were reported in 15% (8/55) of patients in SA vs. 10% (6/60) in CA, P = 0.46. One death was reported after SA. Improvements in AF symptoms were greater following CA. Over 12 months, SA was more expensive and provided fewer quality-adjusted life-years (QALYs) compared with CA (0.78 vs. 0.85, P = 0.02). CONCLUSION: Single procedure thoracoscopic SA is not superior to CA in treating LSPAF. Catheter ablation provided greater improvements in symptoms and accrued significantly more QALYs during follow-up than SA. CLINICAL TRIAL REGISTRATION: ISRCTN18250790 and ClinicalTrials.gov: NCT02755688.

Nonatherosclerotic Abdominal Vasculopathies.

BACKGROUND: Nonatherosclerotic abdominal arterial vasculopathies (NAVs), including mesenteric or renal artery dissection, aneurysm, stenosis, and vasculitis, are rare but have great clinical significance. Patients may present emergently with life-threatening complications such as arterial rupture and hemorrhagic shock. Herein, we present our center's experience with NAVs and provide extensive literature review to close the gap in the scarce, related literature. METHODS: From a single-center retrospective data analysis, we identified and characterized subjects (aged 18-60 years) who presented with NAV between January 2000 and December 2015. Of the 1416 charts reviewed, 118 met inclusion criteria. RESULTS: The average age of patients with NAV was 47.0 ± 9.9 years, mostly affecting women (64%). Primary diagnoses included fibromuscular dysplasia (FMD) (25.4%), isolated aneurysms (24.6%), and median arcuate ligament syndrome (MALS) (15.3%). Less common diagnoses were localized vasculitis of the gastrointestinal tract (LVGT) (7.6%), isolated dissection (5.1%), microscopic polyangiitis and granulomatosis with polyangiitis (5.1%), trauma (4.2%), segmental arterial mediolysis (4.2%), Ehlers-Danlos syndrome (2.5%), Takayasu's arteritis (2.5%), polyarteritis nodosa (1.7%), idiopathic abdominal aortitis (0.8%), and Loeys-Dietz syndrome (0.8%). Females constituted 90% of patients with FMD, 77.8% with MALS, 77.8% with isolated aneurysms, 66.7% with Takayasu arteritis, and 55.6% with LVGT. Prevalent comorbidities included tobacco use (43.6%) and hypertension (52.1%). Coil embolization was used in 14.4%, anticoagulation in 11.9%, angioplasty/stenting in 11.9%, open resection/surgical revascularization in 10.2%, and prednisone in 10.2% of the cases. Conservative management was pursued in 33.1% of the patients. A high degree of symptom relief was shown in 91.7%. CONCLUSIONS: NAV are rare and can be caused by different etiologies that primarily affect females. Hypertension and tobacco use were prevalent. Various imaging strategies revealed aneurysms, stenosis, dissection, and/or thrombosis affecting renal and celiac arteries. Most patients improved with conservative, medical, endovascular, or surgical approach. More research is needed to standardize management approach to patients with NAV.

Results of the first investigator-initiated randomized clinical trial of nMARQTM, PVACTM, and thoracoscopic ablation for paroxysmal atrial fibrillation.

Aims: To investigate the effect of minimally invasive thoracoscopic surgical ablation and nMARQ irrigated multi-electrode phased radiofrequency (RF) ablation to treat paroxysmal atrial fibrillation (AF) compared with PVAC multi-electrode phased RF ablation, with beat-to-beat device-derived Holter monitoring throughout the study duration. Methods and results: An investigator-initiated prospective trial of patients with paroxysmal AF randomized (1:1:1) to initial surgical, nMARQ or PVAC ablation. All patients had continuous beat-to-beat monitoring with an ILR or pacemaker to evaluate and document AF recurrence. There was a strong trend (P = 0.050) toward difference in AF outcome, with surgical AF ablation more efficacious than catheter ablation. At one year, the proportion of patients with less than 1% AF burden after one procedure and off all antiarrhythmic drugs was 63, 56, and 90% for PVAC, nMARQ and surgical ablations respectively. There were significantly more repeat ablations in the catheter ablation groups (P = 0.008): 25% PVAC, 27% nMARQ, 0% surgery. However, 7 of 20 (35%) of patients undergoing surgical ablation suffered a procedural complication, including two sternotomies for bleeding and one death. This was higher than for catheter ablation (P < 0.001). Surgical ablation took longer to perform (P < 0.001) and had a longer hospital admission (P < 0.001) than catheter ablation. Conclusion: Surgical AF ablation required significantly fewer repeat procedures than catheter ablation, and there was a clear trend towards improved arrhythmia outcome. However, it was associated with a significantly higher rate of procedural complications. Surgical ablation for paroxysmal AF is promising, however more prospective outcome data is required. Clinical Trial Registration: NCT01504451, http://clinicaltrials.gov/show/NCT01504451.

Extensive Cerebrovascular and Visceral Artery Dissection and Pseudoaneurysm with Underlying Segmental Arterial Mediolysis.

Segmental arterial mediolysis (SAM) is a nonatherosclerotic, nonhereditary vasculopathy that most commonly involves abdominal aortic branches and predominantly affects middle-age and elderly populations. Lysis of the outer arterial media results in separation of the media from the adventitia leading to dissecting aneurysms and/or pseudoaneurysms. We report a unique case of a 47-year-old man who presented with bilateral internal carotid artery dissection followed by dissections and aneurysms involving multiple visceral arteries. This case highlights the dramatic manifestation of SAM and discusses the complexity of decision-making related to this disease including differential diagnoses and management.

Detecting Clusters in Atom Probe Data with Gaussian Mixture Models.

Accurately identifying and extracting clusters from atom probe tomography (APT) reconstructions is extremely challenging, yet critical to many applications. Currently, the most prevalent approach to detect clusters is the maximum separation method, a heuristic that relies heavily upon parameters manually chosen by the user. In this work, a new clustering algorithm, Gaussian mixture model Expectation Maximization Algorithm (GEMA), was developed. GEMA utilizes a Gaussian mixture model to probabilistically distinguish clusters from random fluctuations in the matrix. This machine learning approach maximizes the data likelihood via expectation maximization: given atomic positions, the algorithm learns the position, size, and width of each cluster. A key advantage of GEMA is that atoms are probabilistically assigned to clusters, thus reflecting scientifically meaningful uncertainty regarding atoms located near precipitate/matrix interfaces. GEMA outperforms the maximum separation method in cluster detection accuracy when applied to several realistically simulated data sets. Lastly, GEMA was successfully applied to real APT data.

Analysis of Radiation Damage in Light Water Reactors: Comparison of Cluster Analysis Methods for the Analysis of Atom Probe Data.

Irradiation of reactor pressure vessel (RPV) steels causes the formation of nanoscale microstructural features (termed radiation damage), which affect the mechanical properties of the vessel. A key tool for characterizing these nanoscale features is atom probe tomography (APT), due to its high spatial resolution and the ability to identify different chemical species in three dimensions. Microstructural observations using APT can underpin development of a mechanistic understanding of defect formation. However, with atom probe analyses there are currently multiple methods for analyzing the data. This can result in inconsistencies between results obtained from different researchers and unnecessary scatter when combining data from multiple sources. This makes interpretation of results more complex and calibration of radiation damage models challenging. In this work simulations of a range of different microstructures are used to directly compare different cluster analysis algorithms and identify their strengths and weaknesses.

Diversity and conservation of the genome architecture of phages infecting the Alphaproteobacteria.

IMPORTANCE: This study reports the results of the largest analysis of genome sequences from phages that infect the Alphaproteobacteria class of bacterial hosts. We analyzed over 100 whole genome sequences of phages to construct dotplots, categorize them into genetically distinct clusters, generate a bootstrapped phylogenetic tree, compute protein orthologs, and predict packaging strategies. We determined that the phage sequences primarily cluster by the bacterial host family, phage morphotype, and genome size. We expect that the findings reported in this seminal study will facilitate future analyses that will improve our knowledge of the phages that infect these hosts.

Long-term clinical outcomes and cost-effectiveness of catheter vs thoracoscopic surgical ablation in long-standing persistent atrial fibrillation using continuous cardiac monitoring: CASA-AF randomized controlled trial.

BACKGROUND: Long-term clinical outcomes of catheter ablation (CA) compared to thoracoscopic surgical ablation (SA) to treat patients with long-standing persistent atrial fibrillation (LSPAF) are not known. OBJECTIVE: The purpose of this study was to compare the long-term (36-month) clinical efficacy, quality of life, and cost-effectiveness of SA and CA in LSPAF. METHODS: Participants were followed up for 3 years using implantable loop recorders and questionnaires to assess the change in quality of life. Intention-to-treat analyses were used to report the findings. RESULTS: Of the 115 patients with LSPAF treated, 104 (90.4%) completed 36-month follow-up [CA: n = 57 (95%); SA: n = 47 (85%)]. After a single procedure without antiarrhythmic drugs, 7 patients (12%) in the CA arm and 5 (11%) in the SA arm [hazard ratio 1.22; 95% confidence interval (CI) 0.81-1.83; P = .41] were free from atrial fibrillation/tachycardia (AF/AT) ≥30 seconds at 36 months. Thirty-three patients (58%) in the CA arm and 26 (55%) in the SA arm (hazard ratio 1.04; 95% CI 0.57-1.88; P = .91) had their AF/AT burden reduced by ≥75%. The overall impact on health-related quality of life was similar, with mean quality-adjusted life year estimates of 2.45 (95% CI 2.31-2.59) for CA and 2.32 (95% CI 2.13-2.52) for SA. Estimated costs were higher for SA (mean £24,682; 95% CI £21,746-£27,618) than for CA (mean £18,002; 95% CI £15,422-£20,581). CONCLUSION: In symptomatic LSPAF, CA and SA were equally effective at achieving arrhythmia outcomes (freedom from AF/AT ≥30 seconds and ≥75% burden reduction) after a single procedure without antiarrhythmic drugs. However, SA is significantly more costly than CA. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04280042.

Acute ischemic complications of PCI and CABG: who should cover whom for coronary revascularization?

INTRODUCTION: Percutaneous coronary intervention (PCI) has historically required cardiothoracic backup in the event of ischemic complications. However, many complications occurring during PCI can now be effectively treated at the time of the indexed procedure. Equally, ischemic complications, which occur following coronary artery bypass grafting (CABG), which were previously treated medically or with reoperation, may now also be effectively treated by acute PCI. AIMS AND METHODS: To identify the rate, cause, treatment, and outcomes of ischemic complications from PCI or isolated CABG procedures undertaken from January 2004 to January 2011 where there was immediate crossover from PCI to CABG or vice versa, and to determine from the indexed revascularization procedure, whether or not the ischemic complications were rectified by either CABG with respect to PCI or PCI with respect to CABG. RESULTS: Three hundred fifty-six PCI major ischemic complications were identified. Three hundred forty-seven (97.5%) were rectified percutaneously and 9 (2.5%) required emergency CABG. The commonest reason for emergency CABG was occlusive dissection (n=7). Of the 9 patients that underwent emergency CABG, 3 patients (33.3%) died. Forty CABG major ischemic complications were identified. Twenty-seven (67.5%) were treated medically. Thirteen (32.5%) underwent diagnostic angiography. The etiology of the ischemia was found in all cases. Consequently, 2 underwent reoperation, one was treated medically, and 10 underwent acute PCI. CONCLUSION: Acute coronary ischemia remains a small but significant complication of both PCI and CABG. Resolution of ischemia requires prompt diagnosis and early discussion between cardiothoracic surgeon and cardiac interventionalist to determine the safest and therefore most appropriate way to resolve the problem.

Recurrent strokes caused by a malpositioned pacemaker lead.

This case report illustrates the case of a patient who developed recurrent strokes after a pace maker lead was inserted into his left ventricle. It was removed successfully by the cardiothoracic surgeons but he remained very dependent functionally. This case highlights the importance of always reviewing the electrocardiogram and chest radiograph after the insertion of a pacemaker as late diagnosis of this complication can leave the patient with significant morbidity.

Lumbarized sacrum as a relative contraindication for lateral transpsoas interbody fusion at L5-6.

STUDY DESIGN: Retrospective review. OBJECTIVE: To determine if lumbarized sacra at the L5-6 level (functional L4-5) are a contraindication to a lateral transpsoas approach. SUMMARY OF BACKGROUND DATA: Transitional vertebrae at the lumbosacral junction present mechanical and morphologic changes, though these changes have not been characterized with respect to the feasibility of a lateral transpsoas approach. METHODS: Three hundred fifty-one patients were scheduled for lumbar interbody fusion using a mini-open lateral transpsoas approach (XLIF) at L4-5 from 2004 to 2008 at a single institution. In patients with 6 lumbar vertebrae, accessibility, based on neuromonitoring, of the L5-6 level (functional L4-5) was reviewed. Qualitative assessments using axial magnetic resonance imaging (MRI) were performed and compared with a sample of patients with normal anatomy treated at L4-5. RESULTS: Of the 351 patients scheduled for treatment at L4-5, 10 (2.8%) were determined to have 6 lumbar vertebrae with the symptomatic level at L5-6. Of those 10, 2 (20%) could be treated using a lateral transpsoas approach, and 8 (80%) were converted to another approach after a corridor through the psoas muscle was not found, based on neuromonitoring feedback. Review of axial MRI showed a teardrop-shaped psoas detached from the lateral border of the disc space in patients with transitional anatomy unapproachable at L5-6, resemblant of L5-S1 in normal anatomy. In the 2 patients who could be safely approached, the psoas anatomy at L5-6 was similar to a normal L4-5 level, with a domed/helmet shape, attached laterally to the disc space. CONCLUSIONS: Treating the L5-6 level using a lateral transpsoas approach in individuals with lumbarized sacra can be challenging due to anatomy more similar to the L5-S1 level in normal patients. Preoperative planning using axial MRI and intraoperative adherence to advanced neuromonitoring can aid in identifying and avoiding injury in these rare patients.

Utility of D-dimers in COVID-19 Patients Requiring Extracorporeal Membrane Oxygenation.

A retrospective study was performed examining the trend of inflammatory markers, including D-dimers, in 29 COVID-19 patients requiring veno-venous (VV) extracorporeal membrane oxygenation (ECMO) support. We observed that COVID-19 patients with pre-cannulation D-dimer levels >3,000 ng/mL had a significantly shorter time from admission to cannulation (4.78 vs . 8.44 days, p = 0.049) compared to those with D-dimer <3,000 ng/mL. Furthermore, patients with D-dimer >3,000 ng/mL had a trend of lower pH (7.24 vs . 7.33), higher pCO 2 (61.33 vs . 50.69), and higher vasoactive inotropic score (7.23 vs . 3.97) at time of cannulation, however, these were not statistically significant. This cohort of patients also required a longer duration of ECMO support (51.44 vs . 31.25 days). However, 13 patients required at least one ECMO-circuit exchange and 16 patients did not require any exchanges. There was a consistent drop in D-dimer values after every circuit exchange, which was not observed in any of the other examined inflammatory markers, including ferritin, lactate dehydrogenase, or C-reactive protein. We propose that elevated D-dimer levels (>3,000 ng/mL) reflect increased disease severity in COVID-19, and predict a longer ECMO course. Once on ECMO, however, the D-Dimer level consistently decreased with every circuit exchange, which may reflect thrombus within the oxygenator rather than just disease severity.

Undetected carriage explains apparent Staphylococcus aureus acquisition in a non-outbreak healthcare setting.

OBJECTIVES: Previous studies have been unable to identify patient or staff reservoirs for the majority of the nosocomial S. aureus acquisitions which occur in the presence of good infection control practice. We set out to establish the extent to which undetected pre-existing carriage explains apparent nosocomial S. aureus acquisition. METHODS: Over two years elective cardiothoracic admissions were screened for S. aureus carriage before and during hospital admission. Routine screening (nose/groin/wound sampling), was supplemented by sampling additional body sites (axilla/throat/rectum) and culture-based methods optimised to detect fastidious phenotypes (small colony variants, cell wall deficient variants) and molecular identification by PCR. RESULTS: 35% of participants (53/151) were S. aureus carriers according to routine pre-healthcare screening; increasing to 42% (63/151) when additional body sites and enhanced cultures were employed. 71% (5/7) of apparent acquisitions were explained by pre-existing carriage using augmented measures. Enhanced culture identified a minority of colonised individuals (3/151 including 1 MRSA carrier) who were undetected by routine and additional screening cultures. 4/14 (29%) participants who became culture-negative during admission had S. aureus genomic material detected at discharge. CONCLUSIONS: Conventional sampling under-estimates carriage of S. aureus and this explains the majority of apparent S. aureus acquisitions among elective cardiothoracic patients.

Percutaneous Management of Coronary Button Kinking After Emergency Aortic Root Replacement.

Surgical management of type A acute aortic dissection by the Bentall procedure involves attachment of the native coronary arteries to a synthetic valved-graft conduit (mechanical or biological aortic valve). In patients with normal anatomy and with careful surgical technique, formation of coronary buttons has been successful, and anastomotic complications after this procedure are rare. However, we describe the development of postoperative myocardial ischemia in a 46-year-old man caused by coronary button kinking after the Bentall procedure and reflect how one may avoid returning to the operating theater and still achieve a good outcome.

An ascending aortic mass infected with Citrobacter koseri in a young woman.

BACKGROUND: Isolated aortic infection is rare and is typically associated with an underlying aortic aneurysm or a prosthetic aortic graft. CASE SUMMARY: A 38-year-old woman was admitted with symptoms of left upper limb ischaemia and had imaging findings suggestive of thrombus extending from the ascending aorta into the subclavian and brachial arteries. She underwent evacuation of the aortic masses and replacement of the ascending aorta. Citrobacter koseri was isolated from the excised tissue and the patient received 6 weeks of appropriate antibiotic therapy. DISCUSSION: This is an unusual case of acute upper limb ischaemia due to a mass infected with Citrobacter koseri in the ascending aorta without heart valve involvement.

Intraoperative MRI versus 5-ALA in high-grade glioma resection: a network meta-analysis.

OBJECTIVE: High-grade gliomas (HGGs) continue to carry poor prognoses, and patient outcomes depend heavily on the extent of resection (EOR). The utility of conventional image-guided surgery is limited by intraoperative brain shift. More recent techniques to maximize EOR, including intraoperative imaging and the use of fluorescent dyes, combat these limitations. However, the relative efficacy of these two techniques has never been systematically compared. Thus, the authors performed an exhaustive systematic review in conjunction with quantitative network meta-analyses to evaluate the comparative effectiveness of 5-aminolevulinic acid (5-ALA) and intraoperative MRI (IMRI) in optimizing EOR in HGG. They secondarily analyzed associated progression-free and overall survival and performed subgroup analyses by level of evidence. METHODS: PubMed, Embase, Cochrane Central, and Web of Science were searched for studies evaluating conventional neuronavigation, IMRI, and 5-ALA in HGG resection. The primary study endpoint was the proportion of patients attaining gross-total resection (GTR), defined as 100% elimination of contrast-enhancing lesion on postoperative MRI. Secondary endpoints included overall and progression-free survival and subgroup analyses for level of evidence. Comparative efficacy analysis of IMRI and 5-ALA was performed using Bayesian network meta-analysis models. RESULTS: This analysis included 11 studies. In a classic meta-analysis, both IMRI (OR 4.99, 95% CI 2.65-9.39, p < 0.001) and 5-ALA (OR 2.866, 95% CI 2.127-3.863, p < 0.001) were superior to conventional navigation in achieving GTR. Bayesian network analysis was employed to indirectly compare IMRI to 5-ALA, and no significant difference in GTR was found between the two (OR 1.9 favoring IMRI, 95% CI 0.905-3.989, p = 0.090). A handful of studies additionally suggested that the use of either IMRI (2 and 4 studies, respectively) or 5-ALA (2 and 2 studies, respectively) improves progression-free and overall survival. CONCLUSIONS: IMRI and 5-ALA are individually superior to conventional neuronavigation for achieving GTR of HGG. Between IMRI and 5-ALA, neither method is clearly more effective. Future studies evaluating the comparative cost and surgical time associated with IMRI and 5-ALA will better inform any cost-benefit analysis.

Ablation in Atrial Fibrillation with Ventricular Pacing Results in Similar Spatial Catheter Stability as Compared to Ablation in Sinus Rhythm with Atrial Pacing.

BACKGROUND: Improved catheter stability is associated with decreased arrhythmia recurrence after atrial fibrillation (AF) ablation. Recently, atrial voltage mapping in AF was demonstrated to correlate better with scar as compared to mapping in sinus rhythm (SR). However, it is unknown whether ablation of persistent AF in sinus rhythm with atrial pacing or in atrial fibrillation with ventricular pacing results in differences in catheter stability or arrhythmia recurrence. METHODS: We analyzed 53 consecutive patients undergoing first-time persistent AF ablation with pulmonary vein and posterior wall isolation: 27 were cardioverted, mapped, and ablated in sinus rhythm with atrial pacing, and 26 were mapped and ablated in AF with ventricular pacing. Ablation data was extracted from the mapping system and analyzed using custom MATLAB software to determine high-frequency (60Hz) catheter excursion as a novel metric for catheter spatial stability. RESULTS: There was no difference in catheter stability as assessed by maximal catheter excursion, mean catheter excursion, or contact force variability between the atrial-paced and ventricular-paced patients. Ventricular-paced patients had significantly greater mean contact force as compared to atrial-paced patients. Contact-force variability demonstrated poor correlation with catheter excursion. One year arrhythmia-free survival was similar between the atrial paced and ventricular paced patients. CONCLUSIONS: For patients with persistent AF, ablation in AF with ventricular pacing results in similar catheter stability and arrhythmia recurrence as compared to cardioversion and ablation in sinus rhythm with atrial pacing. Given the improved fidelity of mapping in AF, mapping and ablating during AF with ventricular pacing may be preferred.

Antithrombotic therapy after bioprosthetic aortic valve replacement: ACTION Registry survey results.

AIMS: A variety of antithrombotic regimens have been described for the early postoperative period after bioprosthetic aortic valve replacement (AVR). This study reviews antithrombotic practice for patients undergoing bioprosthetic AVR with or without coronary artery bypass graft (CABG) amongst the centers participating in the ACTION (Anticoagulation Treatment Influence on Postoperative Patients) Registry. METHODS AND RESULTS: An antithrombotic therapy questionnaire was answered by the 49 centers participating in the ACTION Registry located in Europe, Middle East, Canada and Asia. The 43% of centers prescribe vitamin K antagonist (VKA), 20% prescribe VKA and acetyl salicylic acid (ASA), 33% prescribe only ASA and 4% do not prescribe any therapy after bioprosthetic AVR. For patients undergoing bioprosthetic AVR and CABG 39% of the centers prescribe VKA and ASA, 37% prescribe VKA and 24% prescribe ASA. After the first three postoperative months following bioprosthetic AVR, 61% of the centers prescribe only ASA, while 39% do not prescribe any therapy. Patients with bioprosthetic AVR and CABG receive ASA in 90% centers, in 2% centers VKA and ASA, and 8% centers do not prescribe any antithrombotic. CONCLUSION: This study demonstrates that, despite guidelines published by several professional societies, medical practice for the prevention of thrombotic events early after bioprosthetic AVR varies widely among cardiac surgical centers.

A critical evaluation of discography in patients with lumbar intervertebral disc disease.

STUDY DESIGN: The study is a prospective observational study of 48 continuous patients with symptomatic lumbar degenerative disk disease. Each patient underwent discography, MRI, and a biochemical analysis of disk lavage fluid. OBJECTIVES: The purpose of this study was to correlate concordant pain on discography with MRI grade and biochemical markers of inflammation in a clinical setting. SUMMARY OF BACKGROUND DATA: The pathophysiology of degenerative disk disease is complex. Discography is used to differentiate symptomatic from asymptomatic levels. MRI is used to image changes in disk water content. Biochemical assays have identified molecular markers of inflammation. To date, no study has correlated concordant pain on discography with MRI findings and biochemical markers. METHODS: Forty-eight (48) continuous patients with symptomatic lumbar degenerative disk disease gave informed consent for study entry. Patient sex, age, insurance, work status and visual analog score (VAS) were recorded. MRI was obtained and Pfirrmann grading was performed by a single spine surgeon. Discography with disc lavage was performed by a single anesthesiologist. Lavage samples were tested for inflammatory markers with high resolution multi-plex bead immunoassays and ELISA with >5 pg/ml resolution. RESULTS: None of demographic variables was significantly related to concordant pain on discogram by chi-squared tests and Mann-Whitney U-test. The Pfirrmann score was significantly different for patients with and without concordant pain at L3-L4 (p<0.001), but was insignificant at other levels after multitest correction. Pfirrmann scores were significantly different at any level in patients with and without concordant pain. VAS scores were not significantly correlated with opening pressures at any level. Despite the presence of serum proteins in the disk lavage fluid, none of the tested inflammatory mediators was identified by multi-plex bead immunoassays and ELISA. CONCLUSIONS: There are only weak correlations between demographic, discogram, and radiographic variables. Response to discogram cannot be predicted by non-invasive means. The disk lavage method was unable to identify the presence of specific inflammatory peptides with multi-plex immunoassays and ELISA.