Usefulness of Echo-Guided Cardiac Resynchronization Pacing in Patients Undergoing “Ablate and Pace” Therapy for Permanent Atrial Fibrillation and Effects of Heart Rate Regularization and Left Ventricular Resynchronization

• Published in: The American journal of cardiology Vol. 102; no. 7; pp. 854 - 860
• Main Authors: Brignole, Michele, MD, Menozzi, Carlo, MD, Botto, Gian Luca, MD, Mont, Lluís, MD, Osca Asensi, Joaquín, MD, García Medina, Dolores, MD, Oddone, Daniele, MD, Navazio, Alessandro, MD, Luzi, Mario, MD, Iacopino, Saverio, MD, De Fabrizio, Giuseppe, MD, Proclemer, Alessandro, MD, Vardas, Panos, MD
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier 01-10-2008; Elsevier Limited
• Subjects: Aged; Atrial Fibrillation - diagnostic imaging; Atrial Fibrillation - physiopathology; Atrial Fibrillation - therapy; Atrioventricular Node - surgery; Biological and medical sciences; Cardiac arrhythmia; Cardiac dysrhythmias; Cardiac Pacing, Artificial - methods; Cardiology; Cardiology. Vascular system; Cardiovascular; Catheter Ablation; Combined Modality Therapy; Comparative studies; Echocardiography, Doppler; Female; Heart; Heart rate; Heart Rate - physiology; Heart surgery; Humans; Male; Medical imaging; Medical sciences; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); ROC Curve; Statistics, Nonparametric; Treatment Outcome; Ultrasonography, Interventional; Ventricular Dysfunction, Left - diagnostic imaging; Ventricular Dysfunction, Left - physiopathology; Ventricular Dysfunction, Left - therapy; Cardiac resynchronization; Arrhythmia; Permanent; Echo; Atrial fibrillation; Instrumentation therapy; Cardiovascular disease; Excitability disorder; Left ventricle; Guidance; Heart rate; Instrumental stimulation; Bradycardia; Pacemaker; Heart disease; Circulatory system; Cardiology
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/j.amjcard.2008.05.024

An acute comparative study of right ventricular (RV) pacing and echocardiographically guided cardiac resynchronization pacing (CRP) was performed in patients who underwent “ablate and pace” therapy for permanent atrial fibrillation. It was hypothesized that optimized CRP guided by tissue Doppler echocardiography would exert an additive beneficial hemodynamic effect to that of rate regularization achieved through atrioventricular junction ablation. An acute intrapatient comparison of echocardiographic parameters was performed between baseline preablation values and RV pacing and CRP (performed <24 hours after ablation) in 50 patients. Optimized CRP configuration was defined as the modality of pacing corresponding to that of the shortest intra–left ventricular (LV) delay among simultaneous biventricular pacing, sequential biventricular pacing, and single-chamber pacing. The intra-LV delay was defined as the difference between the longest and the shortest activation time in the six basal segments of the left ventricle. Compared with preablation measures, the ejection fraction increased by 10.8% during RV pacing (19% in patients with intra-LV delays <47.5 ms and 3% in those with intra-LV delays >47.5 ms). Compared with RV pacing, CRP caused a 9.2% increase in the ejection fraction, a 6.8% decrease in LV systolic diameter, and a 17.3% decrease in mitral regurgitation area; LV dyssynchrony was reduced from 52 ± 27 to 21 ± 12 ms. Similar results were observed in patients with and without depressed systolic function and in patients with and without left bundle branch block. In conclusion, rate regularization achieved through atrioventricular junction ablation and RV pacing provides a favorable hemodynamic effect that is inversely related to the level of LV dyssynchrony. Minimizing LV dyssynchrony by means of optimized CRP yields an additional important benefit.