The QRS widening by ventricular conventional pacing impairs the systolic and diastolic functions and increases mitral regurgitation. The aim of this study was to compare conventional pacing to an alternative stimulation mode with a narrower QRS using two leads in the RV. Thirty-nine (25 men, 14 women; mean age 60.1 +/- 15.1 years) dilated cardiomyopathy patients (Chagas' disease [n = 17], coronariopathy [n = 9], AV ablation for tachycardiomyopathy [n = 3], and other [n = 10]) with cardiac failure (NYHA 3.1 +/- 0.8), pacemaker indication, and chronic AV block (22 AF) had endocardial pacemaker implantations (27 Biotronik, 12 Guidant). Two RV leads (one septal, one conventional [RV apex] were connected, respectively, to the atrial and ventricular pacemaker plugs. After clinical stabilization they were studied under three stimulation modes in the same session: AAI (septal), VVI (conventional), and ventricular endocardial right bifocal stimulation (VERBS) (DDT/DVI/DDD = AV interval = 15/10 ms). In comparison to conventional pacing, VERBS increased ejection fraction (0.124), cardiac output (19.5%), and peak filling rate (31.0%), and decreased QRS duration (24.7%), left atrium area (11.9%), mitral regurgitation area (32.3%), the diastolic transmitral flow (E/A relation) (19.3%), and the propagation flow time (18.0%) from the mitral valve to the left ventricular apex (tE_col), (P < 0.05). The quality-of-life showed an impressive score reduction of 50.4%. The septal stimulation alone showed a less expressive benefit. In severe dilated cardiomyopathy with classic pacemaker indication, VERBS showed significantly better performance than the septal or the conventional stimulation alone. There was a good systolic and a remarkable diastolic improvement causing an important reduction in the quality-of-life score.
BackgroundHeart failure and atrial fibrillation (AF) often coexist in a deleterious
cycle.ObjectiveTo evaluate the clinical and echocardiographic outcomes of patients with
ventricular systolic dysfunction and AF treated with radiofrequency (RF)
ablation.MethodsPatients with ventricular systolic dysfunction [ejection fraction (EF) <50%]
and AF refractory to drug therapy underwent stepwise RF ablation in the same
session with pulmonary vein isolation, ablation of AF nests and of residual atrial
tachycardia, named "background tachycardia". Clinical (NYHA functional class) and
echocardiographic (EF, left atrial diameter) data were compared (McNemar test and
t test) before and after ablation.Results31 patients (6 women, 25 men), aged 37 to 77 years (mean, 59.8±10.6), underwent RF
ablation. The etiology was mainly idiopathic (19 p, 61%). During a mean follow-up
of 20.3±17 months, 24 patients (77%) were in sinus rhythm, 11 (35%) being on
amiodarone. Eight patients (26%) underwent more than one procedure (6 underwent 2
procedures, and 2 underwent 3 procedures). Significant NYHA functional class
improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35;
p<0.0001). The echocardiographic outcome also showed significant ventricular
function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005) and a
significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm;
p=0.026). No major complications occurred.ConclusionOur findings suggest that AF ablation in patients with ventricular systolic
dysfunction is a safe and highly effective procedure. Arrhythmia control has a
great impact on ventricular function recovery and functional class
improvement.
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