Performance of the REAL-AF Same-Day Discharge Protocol in Patients Undergoing Catheter Ablation of Atrial Fibrillation

BACKGROUND

Same-day discharge (SDD) after catheter ablation of atrial fibrillation (AF) has been widely adopted. Nevertheless, planned SDD has been performed by using subjective criteria rather than standardized protocols.

OBJECTIVES

The goal of this study was to determine the efficacy and safety of the previously described SDD protocol in a prospective multicenter study.

METHODS

Using the REAL-AF (Real-world Experience of Catheter Ablation for the Treatment of Paroxysmal and Persistent Atrial Fibrillation) SDD protocol eligibility criteria (stable anticoagulation, no bleeding history, left ventricular ejection fraction >40%, no pulmonary disease, no procedures within 60 days, and body mass index <35 kg/m2), operators prospectively determined whether patients undergoing ablation of AF were candidates for SDD (SDD vs non-SDD groups). Successful SDD was achieved if the patient met the protocol discharge criteria. The primary efficacy endpoint was the success rate of SDD. The primary safety endpoints were readmission rates as well as acute and subacute complications. The secondary endpoints included procedural characteristics and freedom from all-atrial arrhythmias.

RESULTS

A total of 2,332 patients were included. The REAL-AF SDD protocol identified 1,982 (85%) patients as potential candidates for SDD. The primary efficacy endpoint was achieved in 1,707 (86.1%) patients. The readmission rate for SDD vs non-SDD group was similar (0.8% vs 0.9%; P = 0.924). The SDD group had a lower acute complication rate than the non-SDD group (0.8% vs 2.9%; P < 0.001), and there was no difference in the subacute complication rate between groups (P = 0.513). Freedom from all-atrial arrhythmias was comparable between groups (P = 0.212).

CONCLUSIONS

In this large, multicenter prospective registry, the use of a standardized protocol showed the safety of SDD after catheter ablation of paroxysmal and persistent AF. (Real-world Experience of Catheter Ablation for the Treatment of Paroxysmal and Persistent Atrial Fibrillation [REAL-AF]; NCT04088071).

Markers of coagulation and hemostatic activation aid in identifying causes of cryptogenic stroke

OBJECTIVE

To test the hypothesis that markers of coagulation and hemostatic activation (MOCHA) help identify causes of cryptogenic stroke, we obtained serum measurements on 132 patients and followed them up to identify causes of stroke.

METHODS

Consecutive patients with cryptogenic stroke who met embolic stroke of undetermined source (ESUS) criteria from January 1, 2017, to October 31, 2018, underwent outpatient cardiac monitoring and the MOCHA profile (serum D-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex, and fibrin monomer) obtained ≥2 weeks after the index stroke; abnormal MOCHA profile was defined as ≥2 elevated markers. Prespecified endpoints monitored during routine clinical visits included new atrial fibrillation (AF), malignancy, venous thromboembolism (VTE), or other defined hypercoagulable states (HS).

RESULTS

Overall, 132 patients with ESUS (mean age 64 ± 15 years, 61% female, 51% nonwhite) met study criteria. During a median follow-up of 10 (interquartile range 7-14) months, AF, malignancy, VTE, or HS was identified in 31 (23%) patients; the 53 (40%) patients with ESUS with abnormal MOCHA were significantly more likely than patients with normal levels to have subsequent new diagnoses of malignancy (21% vs 0%, p < 0.001), VTE (9% vs 0%, p = 0.009), or HS (11% vs 0%, p = 0.004) but not AF (8% vs 9%, p = 0.79). The combination of 4 normal MOCHA and normal left atrial size (n = 30) had 100% sensitivity for ruling out the prespecified endpoints.

CONCLUSION

The MOCHA profile identified patients with cryptogenic stroke more likely to have new malignancy, VTE, or HS during short-term follow-up and may be useful in direct evaluation for underlying causes of cryptogenic stroke.

Abstract WMP118: Anticoagulation Therapy Reduces Recurrent Stroke in Embolic Stroke of Undetermined Source (ESUS) Patients With Elevated Coagulation Markers or Severe Left Atrial Enlargement

Introduction: Left atrial enlargement (LAE) and markers of coagulation and hemostatic activation (MOCHA) have previously been shown to identify ESUS patients who are more likely to have subsequent diagnosis of atrial fibrillation (AF), malignancy or recurrent strokes. The objective of this study was to evaluate if anticoagulation therapy reduces recurrent stroke in ESUS patients with LAE or abnormal MOCHA.

Methods: Consecutive ESUS patients seen in the Emory Clinic from January 1, 2017, to June 30, 2019, underwent outpatient cardiac monitoring and the MOCHA profile (serum d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex and fibrin monomer) obtained ≥ 2 weeks after the index stroke. All patients were on antiplatelet therapy at the time of testing. Anticoagulation was offered to patients with an abnormal MOCHA (≥ 2 elevated markers) or severe LAE (LA volume index >40 ml/m 2 ). Patients were evaluated for AF, malignancy, recurrent stroke or hemorrhage at routine clinical follow-up. We compared this patient cohort (cohort 2) to a historical cohort (cohort 1) who underwent the same protocol but remained on antiplatelet therapy during follow-up.

Results: Baseline characteristics and endpoints are shown in the Table. Overall 46 (23%) patients in Cohort 2 initiated anticoagulation based on abnormal MOCHA or severe LAE. Cohort 2 had significantly lower rates of recurrent stroke than cohort 1 (14% vs. 3%, p=0.008) with no major hemorrhages.

Conclusion: Anticoagulation therapy in a subgroup of ESUS patients with abnormal MOCHA or severe LAE may be associated with a reduced rate of recurrent stroke. A prospective, multicenter study is warranted to validate these results.

P1019Validation of a risk score to predict the need for pacemaker implantation after transcatheter aortic valve replacement

Background

New conduction abnormalities necessitating pacemaker implantation (PMI) is a common occurrence after TAVR. There is an increased rate of PMI in the those receiving the most contemporary implanted valve, the Edwards Sapien-3 (S3), compared to prior generation balloon expandable valves. We previously described predictors of PMI in a large cohort. Herein we sought to validate these predictors of PMI in a subsequent validation cohort.

Methods

We evaluated all patients undergoing first time elective TAVR with S3 at our institution (n=326). We developed a risk score based on a predictive model we have previously described. Patients received one point for each of the following: history of syncope, oversizing of the valve >16%, baseline right bundle branch block morphology, and two points for a QRS duration >115 ms. We performed regression analysis of the risk score and need for PMI. We also evaluated the performance of the risk score using ROC analysis.

Results

Thirty patients (8%) of the total cohort had need for PMI after S3 implantation. Those with PMI had a higher rate of pre-existing infra-nodal conduction system disease – including QRS duration >115ms (57% vs. 20%, p<0.001) and right bundle branch block (RBBB) morphology (47% vs. 10%, p<0.001) - as well as more frequent valve oversizing >15.7% (47% vs. 23%, p<0.01). There was no significant difference in a history of syncope (10% vs. 8%, p=0.72) between groups. The PMI risk score had an area under the curve of 0.753 on ROC analysis. The PMI risk score was significantly associated with PMI (OR 2.37; 95% CI [1.64–3.34], p<0.001).

Rate of PMI Stratified by Risk Score

Conclusions

The PMI risk score was strongly predictive of the need for PMI after implantation of the S3 valve in a large validation cohort. The PMI risk score performed well in sensitivity analysis. This PMI risk score represents a simple tool to help further risk stratify patients being considered for TAVR.

Abstract WP529: Anticoagulation Therapy Reduces Recurrent Stroke in Embolic Stroke of Undetermined Source (ESUS) Patients With Elevated Markers of Coagulation and Hemostatic Activation

Introduction: Markers of coagulation and hemostatic activation (MOCHA) have previously been shown to identify ESUS patients who are more likely to have subsequent diagnosis of atrial fibrillation (AF), malignancy, venous thromboembolism (VTE) or other defined hypercoagulable disorders. The objective of this study was to evaluate whether anticoagulation therapy reduces recurrent stroke in ESUS patients with an abnormal MOCHA profile.

Methods: Consecutive ESUS patients seen in the Emory Clinic from January 1, 2017 to June 30, 2018 underwent outpatient cardiac monitoring and the MOCHA profile including serum d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex and fibrin monomer obtained ≥ 2 weeks after the index stroke. All patients were on antiplatelet therapy at the time of MOCHA testing and an abnormal MOCHA profile was defined as ≥ 2 elevated markers. Anticoagulation was offered to patients with an abnormal MOCHA and patients were evaluated for recurrent stroke or hemorrhage at routine clinical follow-up. We compared this patient cohort (cohort 2) to a historical cohort (cohort 1) who underwent the same protocol but remained on antiplatelet therapy during follow-up.

Results: Baseline characteristics were similar between cohorts except that cohort 2 was less likely to have diabetes (43% vs 23%, p=0.004), less likely to have an abnormal MOCHA profile (55% vs 36%, p=0.008) and had a shorter duration of follow-up (mean months 13 vs 7, p=0.0001). Cohorts had similar rates of the composite endpoint of AF, malignancy, VTE or other defined hypercoagulable disorder (33% vs 26%, p=0.43). MOCHA profile was obtained a median of 33 (IQR 15-57) days after index stroke in cohort 2; 41 (36%) patients were offered the option of anticoagulation therapy due to an abnormal MOCHA profile of which 32 (78%) chose anticoagulation. Cohort 2 had significantly lower rates of recurrent stroke than cohort 1 (14% vs. 0.9%, IRR 0.14, p=0.01) with no major hemorrhages seen in either group.

Conclusion: This study suggests that anticoagulation therapy in a subgroup of ESUS patients with abnormal MOCHA profile may be associated with a reduced rate of recurrent stroke. A prospective, randomized study is needed to confirm these findings.

Abstract 122: Markers of Coagulation and Hemostatic Activation Identify Embolic Stroke of Undetermined Source (ESUS) Patients who are at Risk of Recurrent Thrombotic Events on Antiplatelet Therapy: A Validation Study

Introduction: Markers of coagulation and hemostatic activation (MOCHA) have previously been shown to identify ESUS patients who are more likely to have subsequent diagnosis of atrial fibrillation (AF) or malignancy. The objective of this study was to validate these results in a larger ESUS cohort.

Methods: Consecutive ESUS patients seen in the Emory Clinic from January 1, 2017 to June 30, 2018 underwent outpatient cardiac monitoring and the MOCHA profile including serum d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex and fibrin monomer obtained ≥ 2 weeks after the index stroke. All patients were on antiplatelet therapy at the time of MOCHA testing and an abnormal MOCHA profile was defined as ≥ 2 elevated markers. Prespecified endpoints monitored during routine clinical follow-up included diagnosis of AF, malignancy, venous thromboembolism (VTE) or other defined hypercoagulable states.

Results: During the study period, 113 ESUS patients (mean age 64 +/- 15 years, 63% female, 54% non-white) underwent prolonged cardiac monitoring (70% MCOT, 42% ILR) and MOCHA profile testing (median days from stroke 33, IQR 15-57). During a mean follow-up of 7 ± 4 months, AF, malignancy, VTE or other defined hypercoagulable state was identified in 30 (27%) patients; the 41 (36%) ESUS patients with an abnormal MOCHA profile were significantly more likely to have an endpoint than patients with a normal profile (59% vs 8%, p<0.0001). The absence of any elevated MOCHA tests (n=41) had 100% sensitivity for the prespecified endpoints.

Conclusion: In this validation study, we found that the MOCHA profile identified ESUS patients more likely to have AF, malignancy, VTE or other defined hypercoagulable states during follow-up and may identify a subgroup of ESUS patients who could benefit from early anticoagulation; a normal MOCHA profile identifies ESUS patients who have a low risk of developing these endpoints on antiplatelet therapy.

Abstract WP278: Markers of Coagulation and Hemostatic Activation in Embolic Stroke of Undetermined Source (ESUS) Patients With Patent Foramen Ovale

Introduction: Recent randomized trials have shown that patent foramen ovale (PFO) closure combined with antiplatelet therapy in cryptogenic stroke patients ≤ 60 years of age is associated with a reduced risk of stroke compared to antiplatelet therapy alone, presumably by preventing a paradoxical embolism. The objective of this study was to evaluate the MOCHA profile, a sensitive marker of venous thromboembolism (VTE), in ESUS patients with PFO.

Methods: Consecutive ESUS patients ≥ 18 years of age seen in the Emory Clinic from January 1, 2017 to June 30, 2018 underwent testing of MOCHA including serum d-dimer (DD), prothrombin fragment 1.2 (PTF1.2), thrombin-antithrombin (TAT) complex and fibrin monomer (FM). All patients were on antiplatelet therapy at the time of MOCHA testing and an abnormal MOCHA profile was defined as ≥ 2 elevated markers. We compared baseline characteristics and clinical outcomes between patients with and without PFO.

Results: During the study period, 113 ESUS patients (mean age 64 +/- 15 years, 63% female, 54% non-white, 20% PFO) underwent MOCHA profile testing; 37 (32.7%) were ≤ 60 years of age. In the subgroup ≤ 60 years of age, the 11 (23%) PFO+ patients were younger (mean age 40 vs 46, p=0.009), more likely to be white (55% vs 35%, p=0.0001) and had higher ROPE score (median 8 vs 6, p=0.06) than PFO- patients. There was no significant difference between PFO+ and PFO- patients in the frequency of abnormal MOCHA (18% vs 19%), mean DD, PTF1.2, TAT, FM and frequency of VTE (1 event in each group). PFO+ and PFO- patients had a high frequency of migraine with aura (64%, 38%, p=0.15) and headache days in the month prior to stroke (mean 11 vs 5, p=0.72). In multivariable analysis of the overall cohort, age (OR 1.14 1.06-1.22 p<0.001) and ROPE score (OR 2.29 1.13-4.65 p=0.02) were significantly associated with abnormal MOCHA while PFO status (p=0.4) and migraine (p=0.23) were not.

Conclusion: In ESUS patients ≤ 60 years of age, there was no difference in the MOCHA profile between PFO+ and PFO- patients. The high frequency of migraine with aura and headache days in the month prior to stroke regardless of PFO status needs further study to evaluate its role in young ESUS patients.

Coagulation markers and echocardiography predict atrial fibrillation, malignancy or recurrent stroke after cryptogenic stroke

We evaluated the utility of left atrial volume index (LAVI) and markers of coagulation and hemostatic activation (MOCHA) in cryptogenic stroke (CS) patients to identify those more likely to have subsequent diagnosis of atrial fibrillation (AF), malignancy or recurrent stroke during follow-up.Consecutive CS patients who met embolic stroke of undetermined source (ESUS) who underwent transthoracic echocardiography and outpatient cardiac monitoring following stroke were identified from the Emory cardiac registry. In a subset of consecutive patients, d-dimer, prothrombin fragment 1.2, thrombin-antithrombin complex and fibrin monomer (MOCHA panel) were obtained ≥2 weeks post-stroke and repeated ≥4 weeks later if abnormal; abnormal MOCHA panel was defined as ≥2 elevated markers which did not normalize when repeated. We assessed the predictive abilities of LAVI and the MOCHA panel to identify patients with subsequent diagnosis of AF, malignancy, recurrent stroke or the composite outcome during follow-up.Of 94 CS patients (mean age 64 ± 15 years, 54% female, 63% non-white, mean follow-up 1.4 ± 0.8 years) who underwent prolonged cardiac monitoring, 15 (16%) had new AF. Severe LA enlargement (vs normal) was associated with AF (P < .06). In 42 CS patients with MOCHA panel testing (mean follow-up 1.1 ± 0.6 years), 14 (33%) had the composite outcome and all had abnormal MOCHA. ROC analysis showed LAVI and abnormal MOCHA together outperformed either test alone with good predictive ability for the composite outcome (AUC 0.84).We report the novel use of the MOCHA panel in CS patients to identify a subgroup of patients more likely to have occult AF, occult malignancy or recurrent stroke during follow-up. A normal MOCHA panel identified a subgroup of CS patients at low risk for recurrent stroke on antiplatelet therapy. Further study is warranted to evaluate whether the combination of an elevated LAVI and abnormal MOCHA panel identifies a subgroup of CS patients who may benefit from early anticoagulation for secondary stroke prevention.

Atrial Fibrillation Predictors on Mobile Cardiac Telemetry in Cryptogenic Ischemic Stroke

Background and Purpose

The objective of our study was to evaluate magnetic resonance imaging (MRI) and echocardiographic characteristics that would identify patients with cryptogenic ischemic stroke (IS) and transient ischemic attack (TIA) who subsequently developed paroxysmal atrial fibrillation (PAF) on mobile cardiac outpatient telemetry (MCOT).

Methods

All patients with cryptogenic IS or TIA seen at the Emory University Hospital and Emory University Hospital Midtown from January 1, 2009, to June 30, 2013, who underwent MCOT were included in this analysis. Location (cortical, high subcortical, or neither) of current and prior strokes on MRI and left atrial (LA) functional and anatomical echocardiographic parameters were evaluated to determine their association with subsequent detection of PAF.

Results

Of 132 patients, 17 (13%) had evidence of newly diagnosed PAF on MCOT (mean duration of monitoring = 25 days). The presence (vs absence) of ≥1 cortical infarct on baseline MRI was a significant predictor of identifying PAF (odds ratio: 5.2, 95% confidence interval: 1.3-19; P = .01). On baseline echocardiography, patients who had PAF (vs non-PAF) had significantly higher mean LA diameters (4.2 vs 3.7 cm, P = .03) and lower tissue Doppler velocity (a'; 5.5 vs 13.5 cm/s, P = .03). In receiver operating characteristic analysis, the ratio of LA volume index to the septal Doppler velocity (LAVI/a') of >4.6 was associated with a higher likelihood of PAF. Combining MRI with echocardiographic variables did not improve the predictive ability beyond echocardiography alone.

Conclusion

Although the presence of cortical-based infarcts on MRI in patients with cryptogenic IS or TIA increases the likelihood of detecting PAF on MCOT, LA functional and anatomic parameters alone best predicted which patients subsequently had PAF.

Combined Angiography and Late Gadolinium Enhancement Acquisition to Improve Assessment of Pulmonary Vein Isolation for Atrial Fibrillation

PURPOSE

To develop a Shared K-space (SharK) magnetic resonance imaging (MRI) sequence that combines angiographic and late gadolinium enhancement (LGE) acquisitions to improve atrial wall segmentation and scar identification, and to develop a novel visualization method that quantifies scar encirclement of pulmonary veins postablation treatment for atrial fibrillation.

MATERIALS AND METHODS

A SharK sequence was developed and used at 3T to image the left atrium in 11 patients postcryoballoon ablation. The effects of sharing k-space between the angiographic and LGE acquisitions on the accuracy of scar were assessed. The left atrial wall was segmented and points about each pulmonary vein (PV) ostia were projected onto a bullseye to quantitatively compare PV encirclement. The parameters used to quantify encirclement were varied to perform a sensitivity analysis.

RESULTS

Compared to using a complete set of k-space, total atrial scar differences were significant only when sharing >75% k-space (P = 0.014), and 90% sensitivity and specificity for identifying scar was achieved when sharing 50% k-space. In patients, the right PVs showed more intersubject variance in encirclement compared to the left PVs. A 100° anteroinferior portion of the left PVs was always encircled, while the superior segments of both right PVs was ablated in only 6/11 patients.

CONCLUSION

A SharK sequence was developed to combine angiographic and LGE imaging for atrial wall segmentation and scar identification. The PV bullseye quantifies and localizes encirclement about the PVs. The left PVs showed a higher amount of scar encirclement and less variability compared to the right PVs.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:477-486.

Abstract 206: High False Positive Rates of Atrial Fibrillation Detection Among Stroke Patients who Receive Medtronic Implantable Loop Recorders

Introduction: Atrial fibrillation is a known risk factor for the development of stroke. Implantable loop recorders (ILRs) have specific algorithms to detect occult atrial fibrillation and can be used in patients with cryptogenic stroke. There is limited data on the frequency of false positive atrial fibrillation detected by the Medtronic ILR.

Hypothesis: Medtronic ILRs have a high rate of false positives but despite this are still effective at detecting atrial fibrillation in patients with cryptogenic stroke.

Methods: All stroke patients who underwent ILR placement from Jan 1, 2013 to June 30, 2015 were prospectively collected through an administrative database. Baseline and clinical characteristics were retrospectively obtained. A random sampling of ILR tracings identified as atrial fibrillation by the Medtronic algorithm was adjudicated by a board certified electrophysiologist for accuracy.

Results: Among 52 patients with a history of ischemic stroke or TIA (mean age 68±14 years, 58% male, 83% white), there were 166 rhythm strips identified as atrial fibrillation by the Medtronic algorithm which were adjudicated. Of the 166 strips reviewed, 140 (84%) were incorrectly identified as atrial fibrillation; of those false positives, adjudication identified 57% as premature atrial complexes(PACs), 22% as T wave over-sensing, 10% due to noise, 5.0% due to premature ventricular complexes (PVCs), 2.9% due to under-sensing, and 2.9% due to sinus arrhythmia. Of the 38 (73%) patients who had ILR implantation for cryptogenic stroke, 4 (11%) were identified as having true atrial fibrillation by ILR after adjudication over 413 patient-months of monitoring; mean time to atrial fibrillation detection was 93 days after implantation.

Conclusions: Stroke patients who undergo Medtronic ILR placement have high false positive rates of atrial fibrillation detected with the Medtronic algorithm. When adequately reviewed by a trained cardiologist for accuracy, the Medtronic ILRs remain effective at detecting atrial fibrillation in cryptogenic stroke patients.

Performance of 3D, navigator echo-gated, contrast-enhanced, magnetic resonance coronary vein imaging in patients undergoing CRT

PURPOSE

The aims of this study were to evaluate the ability of contrast-enhanced MRI to visualize the coronary veins with validation by the gold standard, X-ray venography, and to determine whether MRI can visualize the coronary vein branch used for left ventricular (LV) lead implantation.

MATERIALS AND METHODS

Nineteen (19) patients undergoing cardiac resynchronization therapy (CRT) received a cardiac MRI at 1.5T 1 week before treatment. Coronary vein images were acquired using a 3D, navigator- and ECG-gated, contrast-enhanced, inversion-recovery, fast low-angle shot (FLASH) sequence. X-ray venography was performed during the CRT procedure to image the coronary venous anatomy and the LV lead location. MRI coronary vein images were graded on a 0-3 scale (0 = nonexistent, 1 = poor, 2 = good, 3 = excellent). MRI and X-ray venogram images were also graded using a binary visible/not visible scheme to compare the visibility of the coronary veins.

RESULTS

The mean visibility scores for the coronary sinus, the posterior interventricular, the posterior vein of the left ventricle, the left marginal vein, and the anterior interventricular were 3.0 ± 0.2, 2.3 ± 0.7, 1.6 ± 1.1, 1.9 ± 0.8 and 2.4 ± 0.9, respectively. When compared to X-ray venography, MRI was capable of visualizing 90% of veins and all of the veins used for LV lead implantation. The vein used for LV lead implantation had an average vein image quality score of 1.9 on MRI images.

CONCLUSIONS

Contrast-enhanced MRI was capable of visualizing 90% of the coronary venous anatomy and was able visualize the vein used for LV lead implantation in all patients.

Abstract 23: Neuroimaging and Echocardiographic Predictors of Paroxysmal Atrial Fibrillation on Outpatient Mobile Cardiac Outpatient Telemetry in Cryptogenic Ischemic Stroke and TIA Patients

Background: The objective of our study was to identify factors on MRI neuroimaging and echocardiography as part of routine workup of patients with cryptogenic ischemic stroke (IS) or transient ischemic attack (TIA) to identify those patients who are likely to have paroxysmal atrial fibrillation (PAF) as detected by subsequent outpatient mobile cardiac outpatient telemetry (MCOT).

Methods: All cryptogenic IS or TIA patients seen at Emory University Hospital and The Emory Clinic from 2009-2013 and who underwent outpatient MCOT were included in this analysis.Using logistic regression, we analyzed the association between lesions seen on MRI FLAIR sequences with PAF and categorized them as the following: Cortical lesions (CL), defined as T2-hyperintense cortical-based infarcts; high subcortical (HS) T2-hyperintense lesions, defined as <5mm beneath the cortex without any cortical involvement, or none. Left atrium (LA) functional and dimensional echocardiographic parameters were evaluated to determine their association with PAF.

Results: Of 132 patients included in this analysis, 17 (13%) had evidence of newly diagnosed PAF on MCOT (mean duration of monitoring=25 days); median age was 72 (IQR: 64-79), 50% were women, diabetes was present in 23%, hypertension in 76%, dyslipidemia in 64%, and active tobacco use in 8%. CL seen on baseline MRI were found to be significant predictors of PAF (OR 5.2, 95 % CI: 1.3-19; p=0.01). HS lesions were not found to be a significant predictor of PAF. On baseline echocardiography, patients who had PAF (vs non-PAF) had significantly higher mean LA diameter (4.2 vs 3.7 cm, p=0.03), lower tissue Doppler velocity (a’) (5.5 vs 13.5 cm/s, p=0.03), a trend toward higher left atrium volume index (LAVI) (37.5 vs 29.2, p=0.07) and mean LAVI/late diastolic Doppler velocity (A) (0.67 vs. 0.37, P= 0.006). The Areas under the Curve (AUC) for the parameters were: LA diameter 71.4%, a’ 92.6%, LAVI 74.6%, LAVI/A 62.5%, LAVI/a’ 67.9%.

Conclusion: Cortical-based infarcts seen on MRI FLAIR sequences and baseline echocardiographic variables may help to predict cryptogenic ischemic stroke or TIA patients who are likely to have PAF identified on outpatient MCOT.

Atrioventricular nodal reentrant tachycardia ablation in the setting of bilateral femoral vein occlusion

Atrioventricular nodal reentrant tachycardia (AVNRT) is the most common supraventricular tachycardia. Ablation of the slow pathway is the treatment of choice for recurrent episodes despite adequate medical therapy. We present an uncommon case of AVNRT ablation using a superior vena cava approach in a patient with bilateral common femoral vein occlusion. This approach appears to be a safe alternative in patients with an absence of an inferior venous access.

Transvenous echo Doppler in baboons: a new window to the cardiovascular system

Ultrasound examinations of the heart and major peripheral arteries have been performed as separate procedures; both potentially limited by suboptimal views in certain subjects and the inability to obtain ideal pictures of particular intracardiac structures. Transvenous ultrasound may offer new advantages in certain areas, we therefore studied six adult baboons using a single-plane 5.5-10 MHz transducer mounted on a 10 French (10F) catheter, introduced via the right femoral vein and positioned under fluoroscopic control. Imaging and Doppler studies were performed to delineate cardiovascular anatomy as well as ventricular function response to positive (dobutamine) and negative inotropic (esmolol) agents. The procedure was safe and feasible in all cases. Clear and novel two-dimensional and flow information were obtained from the iliac arteries, descending aorta, both renal artery origins, ascending aorta, including the aortic arch, main pulmonary artery and its bifurcation, as well as head and neck vessels. Novel intracardiac views were obtained, including right ventricular long axis, left ventricular apex and 'flask' views of the left ventricle. Excellent dynamic information for left ventricular function was also available [e.g. myocardial Vmax of the anterior left ventricular wall was 6.8+/-2.5 cm/s at rest, 14.6+/-5.5 cm/s after dobutamine (P=0.009) and 4.5+/-1 cm/s after esmolol (P=0.03 compared with control)]. We conclude that, in adult primates, transvenous ultrasound safely and reliably provides novel information of cardiovascular structure and function.

Women's lived experience of conceptualizing the self: implications for health care practice

In this article we describe a unique qualitative research design in which we used our own lived experiences as the basis for understanding theories of the self. Our purpose in this study was to (a) broaden current understandings of self theory, (b) juxtapose theories of the self with lived experiences of selfhood, and (c) use these new understandings to inform health care practice. The participants were four Canadian middle-aged female academic and health care practitioners. We conducted unstructured, open-ended interviews. Through a collaborative, interpretive process, four recurring themes emerged from the women's narratives: struggling for authenticity, inner knowing, changing over time, and the contextual self. We address the need for practitioners to understand theories of the self--their own and their clients--and how these theories impact their clinical practice.

The quality of medical evidence in hematology-oncology

PURPOSE

The purpose of this study was to evaluate the quality of the medical evidence available to the clinician in the practice of hematology/oncology.

METHODS

We selected 14 neoplastic hematologic disorders and identified 154 clinically important patient management decision/interventions, ranging from initial treatment decisions to those made for the treatment of recurrent or refractory disease. We also performed a search of the scientific literature for the years 1966 through 1996 to identify all randomized controlled trials in hematology/oncology.

RESULTS

We identified 783 randomized controlled trials (level 1 evidence) pertaining to 37 (24%) of the decision/interventions. An additional 32 (21%) of the decision/interventions were supported by evidence from single arm prospective studies (level 2 evidence). However, only retrospective or anecdotal evidence (level 3 evidence) was available to support 55% of the identified decision/interventions. In a retrospective review of the decision/interventions made in the management of 255 consecutive patients, 78% of the initial decision/interventions in the management of newly diagnosed hematologic/oncologic disorders could have been based on level 1 evidence. However, more than half (52%) of all the decision/interventions made in the management of these 255 patients were supported only by level 2 or 3 evidence.

CONCLUSIONS

We conclude that level 1 evidence to support the development of practice guidelines is available primarily for initial decision/interventions of newly diagnosed diseases. Level 1 evidence to develop guidelines for the management of relapsed or refractory malignant diseases is currently lacking.

Transforming our vision: emancipatory career planning for nurses

Canadian nurses are experiencing profound and often disturbing changes in the health care sector. Not only have the number of jobs decreased but the nature and expectations of those jobs are changing dramatically. While these changes have raised nurses' anxiety, the changes simultaneously have presented nurses with an opportunity to transform their vision of nursing and their role in health care. This article describes a career planning pilot project for nurses which employed Freire's model of emancipatory learning. Based on the theoretical foundations of narrative psychology and critical social theory a series of four workshops were offered. Comments from the evaluation results indicate that the workshop was a transformative experience for the participants. Future implications for career planning for nurses are discussed.

Cloning and characterisation of the Schizosaccharomyces pombe rad8 gene, a member of the SNF2 helicase family

The Schizosaccharomyces pombe rad8 mutant is sensitive to both UV and gamma irradiation. We have cloned the rad8 gene by complementation of the UV sensitivity of a rad8.190 mutant strain. The gene comprises an open reading frame of 3.4 kb which does not contain any introns and is capable of encoding a 1133 amino acid protein of 129 kDa. Deletion of the gene indicates that it is not essential for cell viability. Recognisable motifs are present for a nuclear localisation signal, a RING finger and helicase domains. The predicted protein is a member of the SNF2 subfamily of proteins and shows particular homology to the Saccharomyces cerevisiae RAD5 protein. Double mutant analysis demonstrated that the rad8 mutant is not epistatic to mutants in the excision repair pathway (rad13) or checkpoint pathway (rad9). Analysis of radiation sensitivity though the cell cycle indicates that, unlike most other rad mutants, rad8 is most sensitive to irradiation during the G1/S period.