Atrial flutter termination by overdrive transesophageal pacing and the facilitating effect of oral propafenone

Transesophageal overdrive atrial pacing is effective and safe for atrial flutter termination. The influence of antiarrhythmic drug therapy on this procedure is controversial. In this study, we investigated whether oral propafenone may facilitate this procedure. Thirty patients with type I atrial flutter were randomized into 2 groups in which transesophageal pacing was attempted: group A, without treatment; and group B, after oral administration of propafenone 600 mg. Transesophageal pacing was effective in interrupting atrial flutter in 53% of patients (8 of 15) in group A and in 87% of patients (13 of 15) in group B. A significant lengthening of the flutter cycle was observed with respect to the baseline in patients given propafenone (261 ± 23 vs 217 ± 25, p < 0.01). Sinus rhythm resumed at a shorter paced cycle in group A patients (166 ± 13 vs 187 ± 14 ms, p < 0.01). The transesophageal threshold for stable atrial capture was significantly lower in group A (20.5 ± 0.2 vs 23.3 ± 1.2, p < 0.01). In no patient was the threshold for atrial capture higher than the pain threshold. We did not observe abrupt enhancement of atrioventricular conduction. We conclude that propafenone is effective and safe when used with transesophageal pacing in the termination of atrial flutter. The slowing effect of the drug on intraatrial conduction and the possible stabilizing effect on the reentry circuit appear to be outweighed by the positive effect of propafenone on the excitable gap of the circuit, facilitating its capture and accounting for the beneficial effect of the drug on arrhythmia termination.     

Transnasal transesophageal echocardiography: A new approach for the PFO occlusion in awake patients

Objectives : To reduce risks, discomfort, cost, and operative time for percutaneous patent foramen ovale (PFO) closure, we propose to perform this procedure under transesophageal echo‐guidance using a 10 Fr. catheter introduced through nasal way (TEENW). Background : Transesophageal or intracardiac echocardiography is commonly used to guide percutaneous PFO closure. Sedation needed quite frequently during transesophageal echocardiography, increased patients' discomfort, procedure prolongation, costs, use of both femoral veins, and additional intracardiac manipulations are the main limitations of standard techniques. Methods : We enrolled 20 consecutive patients with a history of cerebral ischemia and PFO with right‐to‐left shunt. In 15 patients Amplatzer® PFO occluder was used, whereas in five patients with longer PFO tunnel (>10 mm) Cardia Intrasept® was selected. Without sedation, a multifrequency monoplane probe, developed for intracardiac echocardiography, was introduced into the nostril and advanced forward the esophagus. Then under echo guidance, the closing device was presented, opened and released. Results : Procedure lasted for an average of 33.3 min, and no complications were seen. At procedure's completion, six patients showed persistence of reduced shunt during Valsalva manoeuvre. At six‐month follow‐up, shunts disappeared in all patients. Conclusion : TEENW is safe and well tolerated, and images' quality is high enough to deserve widespread adoption of this technique for PFO closure. © 2008 Wiley‐Liss, Inc.     

New and Recurrent Colorectal Cancers After Resection: a Systematic Review and Meta-analysis of Endoscopic Surveillance Studies

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Short-term venous stasis influences routine coagulation testing.

Preanalytical variability is a common source of errors in coagulation testing, as clotting assays are particularly susceptible to poor standardization of the whole analytical process. To investigate the effect of a short-term venous stasis on routine coagulation testing, we measured activated partial thromboplastin time, prothrombin time, fibrinogen and D-dimer in plasma specimens collected either without venous stasis or following the application of a 60 mmHg constant, standardized external pressure by a sphygmomanometer, for 1 (1-min stasis) and 3 min (3-min stasis). When compared with blood specimens collected without stasis, the Pearson's correlation coefficients and the corresponding slopes of the Passing and Bablok regression line of samples collected following 1 and 3-min stasis were acceptable. However, statistically significant differences by paired Student's t-test could be observed for all parameters tests following 3-min stasis, and for all but the activated partial thromboplastin time after 1-min stasis. Significant difference between specimens collected after 1- and 3-min stasis was also achieved for prothrombin time (P < 0.01), fibrinogen (P < 0.01) and D-dimer (P < 0.05). The agreement between measurements was yet acceptable after 1-min stasis, but achieved clinical significance for prothrombin time, fibrinogen and D-dimer after 3-min stasis. Taken together, results of the present investigation confirm that the effects of venous stasis during venipuncture are clinically meaningful. As hematocrit values and activities of clotting factors VII, VIII and XII significantly increased, whereas that of activated factor VII remained unchanged, we hypothesize that a short-term venous stasis, as induced by up to 3-min tourniquet placing, might not be sufficient to produce additional procoagulant responses besides hemoconcentration.