Ablation of atrial tachyarrhythmias late after surgical repair of tetralogy of Fallot.

BACKGROUND: Patients with repaired tetralogy of Fallot may develop symptomatic and haemodynamic deterioration for many reasons such as arrhythmia, pulmonary regurgitation, and impairment in ventricular function. We describe a consecutive group of patients whose main clinical problem was atrial tachyarrhythmias. AIMS: To describe the clinical outcome of atrial tachyarrhythmias occurring late after surgical repair of tetralogy of Fallot; to define the circuits/foci responsible for these atrial tachyarrhythmias; to evaluate the outcome of computer-assisted mapping and catheter ablation in this patient group. METHODS AND RESULTS: Consecutive patients with surgically repaired tetralogy of Fallot and atrial tachyarrhythmias, who underwent catheter ablation between January, 2001 and June, 2007, were identified retrospectively from case records. Computer-assisted mapping was performed in all using either EnSite® (St Jude Medical Inc.) arrhythmia mapping and intra-cardiac catheter guidance system or CARTO™ (Biosense Webster Inc.) electroanatomical mapping systems. Ten patients (four males) with a median age of 39 plus or minus 8 years were studied. The total number of atrial tachyarrhythmias identified was 22 (six macro-reentrant, 16 micro-reentrant/focal). In nine patients, catheter ablation led to improvement in arrhythmia episodes and/or symptoms during follow-up of 41 plus or minus 20 months. Following ablation(s), five patients required pacing for pre-existing conduction disease and five needed further surgery for haemodynamic indications. All patients remained on anti-arrhythmic drugs. CONCLUSIONS: Patients with surgically repaired tetralogy of Fallot and atrial tachyarrhythmias typically have multiple arrhythmic circuits/foci arising from a scarred right atrium. Catheter ablation reduces arrhythmia frequency and improves symptoms. However, hybrid management is often required, comprising drugs, pacing, and further surgery tailored to the individual.

EUS-FNA versus biliary brushings and assessment of simultaneous performance in jaundiced patients with suspected malignant obstruction.

CONTEXT: Individuals with suspected malignant biliary obstruction commonly undergo ERCP for drainage and tissue sampling via biliary brushings. EUS with EUS-FNA facilitates staging and potentially more accurate tissue sampling. OBJECTIVE: The aim is to compare the diagnostic performance of EUS-FNA and ERCP with biliary brushings (ERCP-BB) in the diagnosis of pancreatobiliary carcinoma and the utility of combining the two procedures under conscious sedation. DESIGN: Retrospective analysis of a prospectively maintained database. PATIENTS: Thirty-seven patients with suspected malignant obstructive jaundice underwent 39 paired procedures, either combined (n=22) or within a few days (n=17). RESULTS: Using strict cytological criteria the sensitivity of EUS-FNA in the diagnosis of malignancy was 52.9% (95% CI: 35.1-70.2%) versus 29.4% (95% CI: 15.1-47.5%) for ERCP-BB. Combining the two tests improved sensitivity to 64.7% (95% CI: 46.5-80.3%) which was significantly better than ERCP-BB alone (P=0.001) but not EUS-FNA alone (P=0.125). When both procedures were performed under the same conscious sedation, there was a significant difference (P=0.031) between the sensitivity of EUS-FNA (52.6%; 95% CI: 28.9-75.6%) and that of ERCP-BB (21.1%; 95% CI: 6.1-45.6%). When both procedures were performed together the mean±SD in-room time was 79±14 min (range: 45-105 min). Two of the patients (9.1%) had a complication. CONCLUSIONS: In patients undergoing EUS-FNA and ERCP-BB under the same sedation, EUS-FNA was significantly more sensitive in diagnosing malignancy. Combining the results of both tests improved diagnostic accuracy. Combining therapeutic ERCP and EUS-FNA under the same conscious sedation is feasible, with a complication rate similar to that of ERCP alone.

Effect of mitral valve repair/replacement surgery on atrial arrhythmia behavior.

BACKGROUND AND AIMS OF THE STUDY: Few data have been published on the effects of mitral valve surgery on atrial rhythm. The study aims were to determine the effects of surgery on: (i) persistence of atrial fibrillation (AF); (ii) measures of left atrial and ventricular dimensions; and (iii) ECG P-wave duration. METHODS: A retrospective case-note review of 92 patients with chronic mitral regurgitation was undertaken. Variables determined included prevalence and duration of AF; incidence of new-onset or persistence of AF after surgery; rhythm changes in relation to age, gender, left atrial and ventricular dimensions and function, anti-arrhythmic drug usage and ECG P-wave duration in sinus rhythm prior to surgery. RESULTS: Only 4/47 (8.5%) patients with any history of AF before surgery were in sinus rhythm at six months after surgery. All 28 patients with persistent AF for >12 months and 41/45 (91%) in sinus rhythm before surgery retained these rhythms after surgery. The left atrial dimension was decreased after surgery, in the whole group (51.3 +/- 9.0 versus 48.4 +/- 9.5 mm; p = 0.011) and in the subgroup in sinus rhythm, but not in the subgroup in AF. The left ventricular end-diastolic dimension decreased in the group as a whole (60.6 +/- 6.2 versus 53.0 +/- 8.7 mm; p = 0.0001) and in both subgroups after surgery. In 24 patients with 12- lead ECGs in sinus rhythm before and three months after surgery, P-wave duration remained unchanged. However, this measure decreased in the 18 patients in sinus rhythm consistently, but increased in the six patients continuing to have paroxysmal AF after surgery. CONCLUSION: Mitral valve surgery alone restored sinus rhythm in only 8.5% of patients with any previous history of AF. Concomitant anti-arrhythmic procedures should be considered for all patients with AF who undergo mitral valve surgery.

Flash pulmonary oedema: a rare but serious side effect of quinine sulphate.

A 54-year-old woman with a background of psoriatic arthritis but no cardiac history was admitted with acute pulmonary oedema (November 2007) which required invasive ventilation and inotropic support. Investigations including ECG, transthoracic and transoesophageal echocardiography, coronary angiography, renal ultrasound and renal magnetic resonance angiography, cardiac MRI and urinary catecholamines were normal. Due to the lack of precipitant, the authors assumed this was due to nabumetone (a non-steroidal anti-inflammatory drug (NSAID)) which was stopped. A second similar episode (August 2008) was temporally associated with a depo steroid injection, although no NSAID was given. Steroids have subsequently been restricted. However, she was admitted again with pulmonary oedema (April 2010) despite not taking NSAIDs or steroids. At that stage, she advised us that she had been taking quinine sulphate on an as required basis and had taken oral doses before each episode of pulmonary oedema which the authors now believe to have been the precipitant.

Surface atrial frequency analysis in patients with atrial fibrillation: assessing the effects of linear left atrial ablation.

INTRODUCTION: Our group has shown previously that measurements of atrial frequency can be obtained from surface 12-lead ECG recordings of patients during atrial fibrillation (AF), using a combination of principal component and Fourier transform algorithms. Such measurements are reproducible over time and change with drug manipulation of the arrhythmia. AIMS: To determine whether linear left atrial ablation, using a combination of "roof" and "mitral isthmus" lines results in changes in surface atrial frequency during AF and to assess the contribution of each individual line when sited sequentially. METHODS AND RESULTS: Computerized recordings from 26 patients, who had undergone linear ablation procedures for AF, were reviewed. The atrial signal was extracted from the 12-lead ECG data by principal component analysis and the main frequency component identified using Fourier analysis. Atrial frequency before and after these two standard ablation lines was compared. Atrial frequency decreased significantly after the combination of roof and mitral isthmus lines (5.66 vs 5.15 Hz) and when either roof (5.61 vs 5.13 Hz) or mitral isthmus (5.89 vs 5.75 Hz) lines were sited first. However, only the roof line led to a significant reduction in atrial frequency when sited second (5.64 vs 5.49 Hz). CONCLUSIONS: Measurements of atrial frequency can be obtained from surface 12-lead ECG recordings during AF and change as predicted in response to linear left atrial ablation. This technique may be useful in assessing antiarrhythmic treatments for AF.

Surface atrial frequency analysis in patients with atrial fibrillation: a tool for evaluating the effects of intervention.

INTRODUCTION: The aims of this study were to evaluate (1) principal component analysis as a technique for extracting the atrial signal waveform from the standard 12-lead ECG and (2) its ability to distinguish changes in atrial fibrillation (AF) frequency parameters over time and in response to pharmacologic manipulation using drugs with different effects on atrial electrophysiology. METHODS AND RESULTS: Twenty patients with persistent AF were studied. Continuous 12-lead Holter ECGs were recorded for 60 minutes, first, in the drug-free state. Mean and variability of atrial waveform frequency were measured using an automated computer technique. This extracted the atrial signal by principal component analysis and identified the main frequency component using Fourier analysis. Patients were then allotted sequentially to receive 1 of 4 drugs intravenously (amiodarone, flecainide, sotalol, or metoprolol), and changes induced in mean and variability of atrial waveform frequency measured. Mean and variability of atrial waveform frequency did not differ within patients between the two 30-minute sections of the drug-free state. As hypothesized, significant changes in mean and variability of atrial waveform frequency were detected after manipulation with amiodarone (mean: 5.77 vs 4.86 Hz; variability: 0.55 vs 0.31 Hz), flecainide (mean: 5.33 vs 4.72 Hz; variability: 0.71 vs 0.31 Hz), and sotalol (mean: 5.94 vs 4.90 Hz; variability: 0.73 vs 0.40 Hz) but not with metoprolol (mean: 5.41 vs 5.17 Hz; variability: 0.81 vs 0.82 Hz). CONCLUSION: A technique for continuously analyzing atrial frequency characteristics of AF from the surface ECG has been developed and validated.