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Atrial Contraction (atrial + contraction)
Selected AbstractsLeft Atrial Radiofrequency Ablation During Cardiac Surgery in Patients with Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2003ROBERTO MANTOVAN M.D. Introduction: Intraoperative left atrial radiofrequency (RF) ablation recently has been suggested as an effective surgical treatment for atrial fibrillation (AF). The aim of this study was to verify the outcome of this technique in a controlled multicenter trial. Methods and Results: One hundred three consecutive patients (39 men and 65 women; age 62 ± 11 years) affected by AF underwent cardiac surgery and RF ablation in the left atrium (RF group). The control group consisted of 27 patients (6 men and 21 women; age 64 ± 7 years) with AF who underwent cardiac surgery during the same period and refused RF ablation. Mitral valve disease was present in 89 (86%) and 25 (92%) patients, respectively (P = NS). RF endocardial ablation was performed in order to obtain isolation of both right and left pulmonary veins, a lesion connecting the previous lines, and a lesion connecting the line encircling the left veins to the mitral annulus. Upon discharge from the hospital, sinus rhythm was present in 65 patients (63%) versus 5 patients (18%) in the control group (P < 0.0001). Mean time of cardiopulmonary bypass was longer in the RF group (148 ± 50 min vs 117 ± 30 min, P = 0.013). The complication rate was similar in both groups, but RF ablation-related complications occurred in 4 RF group patients (3.9%). After a mean follow-up of 12.5 ± 5 months (range 4,24), 83 (81%) of 102 RF group patients were in stable sinus rhythm versus 3 (11%) of 27 in the control group (P < 0.0001). The success rate was similar among the four surgical centers. Atrial contraction was present in 66 (79.5%) of 83 patients in the RF group in sinus rhythm. Conclusion: Endocardial RF left atrial compartmentalization during cardiac surgery is effective in restoring sinus rhythm in many patients. This technique is easy to perform and reproducible. Rare RF ablation-related complications can occur. During follow-up, sinus rhythm persistence is good, and biatrial contraction is preserved in most patients. (J Cardiovasc Electrophysiol, Vol. 14, pp. 1289-1295, December 2003) [source] Surgical Ablation of Permanent Atrial Fibrillation by Means of Maze Radiofrequency:JOURNAL OF CARDIAC SURGERY, Issue 5 2004Mid-Term Results We report our experience with a biatrial pattern of lesions based on the use of epicardial and endocardial radiofrequency ablation in an effort to minimize maze procedure. Method: In 85 patients undergoing cardiac surgery for established permanent atrial fibrillation (>3 months), a biauricular pattern of epicardic,endocardic maze lesions was performed. The main surgical procedures were diverse: 42 mitral valve surgeries, 7 mitrotricuspid valves, 18 mitroaortics, 4 mitroaortic and tricuspids, 2 aortic valves, 3 CABGs, 5 CABG and valve procedures, and 4 atrial septal defects. The mean age of the patients was 61 ± 12 (range 39,78). The mean duration of atrial fibrillation was 5.8 years (range 0.3 to 24). Results: Sixty-two (72.9%) patients presented postoperative supraventricular arrhythmia. Hospital mortality was seen in five patients (5.8%). Two patients died after a 12-month mean follow-up (range 2 to 32). A total of 14.1% of patients remained with their previous atrial fibrillation and 85.9% recovered and maintained sinus rhythm, with two patients having a permanent pacemaker. A total of 56% patients have been followed-up for a period of more than 6 months, and among them prevalence of sinus rhythm is 87.5%. Echocardiography detected biauricular contraction in 65% of them. After analyzing the data, factors involved in postoperative recurrence of atrial fibrillation after radiofrequency surgery were oldness of the atrial fibrillation (p < 0.01) and pre and postoperative left auricle volume (p < 0.04). Conclusion: Intraoperative radiofrequency has permitted us to perform the maze procedure in a simple way, with a low surgical morbid-mortality. We have obtained an 85.9% electrographic effectiveness and a 65% recovery of atrial contraction. Postoperative incidence of arrhythmia is the main postoperative problem. [source] Atrioventricular Nodal versus Atrioventricular Supraventricular Reentrant Tachycardias: Characterization by an Integrated Doppler Electro-physiological Hemodynamic StudyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2000DONATO MELE During reentrant Supraventricular tachycardias involving the atrioventricular node (A VN-SVT) or an A V bypass tract (AV-SVT), atrial pressure increases. While in AVN-SVT this increase relates to atrial contraction during ventricular systole, the mechanism remains unclear in AV-SVT. This study sought to clarify this mechanism. During 11 AVN-SVTs and 9 AV-SVTs. anterograde flow through the AV valves and retrograde flow in the pulmonary and hepatic veins were studied by pulsed- wave (PW) Doppler measuring the time interval between the ECG-R wave and (1) the end of venous retrograde flows, and (2) the beginning of valvular anterograde flows. The positive or negative difference between these two time intervals guided recognizing the atrial contraction against open or closed A V valves. Intracavitary pressures and cardiac index were also measured. During AVN-SVTs, venous retrograde flows always ended before the anterograde valvular flows, indicating atrial contraction against closed AV valves. During A V-SVTs, pulmonary retrograde flow ended before the beginning of mitral anterograde flow in five cases, began before but ended during the anterograde flow in three cases, and overlapped to the anterograde flow in one case. A corresponding behavior was observed at the right side of the heart. In both SVTs, atrial pressures increased and end-dias-tolic ventricular pressure and cardiac index decreased similarly. During AVN-SVT, the atrial contraction always occurs against closed A V valves, and during A V-SVT it generally occurs against totally or partially closed A V valves, explaining similar atrial pressure and cardiac index changes in both SVTs. [source] Is Rhythm-Control Superior to Rate-Control in Patients with Atrial Fibrillation and Diastolic Heart Failure?ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2010Melissa H. Kong M.D. Background: Although no clinical trial data exist on the optimal management of atrial fibrillation (AF) in patients with diastolic heart failure, it has been hypothesized that rhythm-control is more advantageous than rate-control due to the dependence of these patients' left ventricular filling on atrial contraction. We aimed to determine whether patients with AF and heart failure with preserved ejection fraction (EF) survive longer with rhythm versus rate-control strategy. Methods: The Duke Cardiovascular Disease Database was queried to identify patients with EF > 50%, heart failure symptoms and AF between January 1,1995 and June 30, 2005. We compared baseline characteristics and survival of patients managed with rate- versus rhythm-control strategies. Using a 60-day landmark view, Kaplan-Meier curves were generated and results were adjusted for baseline differences using Cox proportional hazards modeling. Results: Three hundred eighty-two patients met the inclusion criteria (285 treated with rate-control and 97 treated with rhythm-control). The 1-, 3-, and 5-year survival rates were 93.2%, 69.3%, and 56.8%, respectively in rate-controlled patients and 94.8%, 78.0%, and 59.9%, respectively in rhythm-controlled patients (P > 0.10). After adjustments for baseline differences, no significant difference in mortality was detected (hazard ratio for rhythm-control vs rate-control = 0.696, 95% CI 0.453,1.07, P = 0.098). Conclusions: Based on our observational data, rhythm-control seems to offer no survival advantage over rate-control in patients with heart failure and preserved EF. Randomized clinical trials are needed to verify these findings and examine the effect of each strategy on stroke risk, heart failure decompensation, and quality of life. Ann Noninvasive Electrocardiol 2010;15(3):209,217 [source] Individualized Selection of Pacing Algorithms for the Prevention of Recurrent Atrial Fibrillation: Results from the VIP RegistryPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2006THORSTEN LEWALTER Objectives: The VIP registry investigated the efficacy of preventive pacing algorithm selection in reducing atrial fibrillation (AF) burden. Background: There are few data identifying which patients might benefit most from which preventive pacing algorithms. Methods: Patients, with at least one documented AF episode and a conventional antibradycardia indication for pacemaker therapy, were enrolled. They received pacemakers with AF diagnostics and four preventive algorithms (Selection and PreventAF series, Vitatron). A 3-month Diagnostic Phase with conventional pacing identified a Substrate Group (>70% of AF episodes with <2 premature atrial contractions [PACs] before AF onset) and a Trigger Group (,70% of AF episodes with <2 PACs before AF onset). This was followed by a 3-month Therapeutic Phase where in the Trigger Group algorithms were enabled aimed at avoiding or preventing a PAC and in the Substrate Group continuous atrial overdrive pacing was enabled. Results: One hundred and twenty-six patients were evaluated. In the Trigger Group (n = 73), there was a statistically significant 28% improvement in AF burden (median AF burden: 2.06 hours/day, Diagnostic Phase vs 1.49 hours/day, Therapy Phase; P = 0.03304 signed-rank test), and reduced PAC activity. There was no significant improvement in AF burden in the Substrate Group (median AF burden: 1.82 hours/day, Diagnostic Phase vs 2.38 hours/day, Therapy Phase; P = 0.12095 signed-rank test), and little change in PAC activity. Conclusions: We identified a subgroup of patients for whom the selection of appropriate pacing algorithms, based on individual diagnostic data, translated into a reduced AF burden. Trigger AF patients were more likely responders to preventive pacing algorithms as a result of PAC suppression. [source] Focal Atrial Fibrillation in DextrocardiaANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2009Takumi Yamada M.D. A 49-year-old woman with dextrocardia and situs inversus underwent catheter ablation of paroxysmal atrial fibrillation (AF). During the electrophysiologic study, AF triggered by frequent premature atrial contractions (PACs) with a short coupling interval exhibiting a "P on T" pattern occurred. Pulmonary vein mapping revealed that those PACs originated from right-sided (anatomic left) or left-sided (anatomic right) pulmonary veins. In this case with mirror-image dextrocardia, the P-wave morphologies in leads I and aVL and the II/III ratio of the P-wave amplitude were helpful for predicting a right- or left-sided pulmonary vein origin. [source] Fetal extrasystole may predict poor neonatal outcomeAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 4 2009Jake A. BROWN Extrasystoles particularly premature atrial contractions noted during labour on the fetal heart rate monitoring strip are usually thought to be benign. In pregnancies complicated by fetal infection and/or the fetal inflammatory response syndrome, there are some data that extrasystoles noted during the intrapartum period may be related to neonatal sepsis and eventual poor neonatal outcome including death or neonatal encephalopathy. Additional observations are needed to substantiate this hypothesis. [source] | ||||||||||