Atrial fibrillation in patients hospitalized for congestive heart failure: the same prognostic influence independently of left ventricular systolic function?

UNLABELLED: Atrial fibrillation (AF) was described to be associated with an adverse prognosis in several studies of heart failure (HF). However, it is not clear whether it directly increased mortality or is only a marker for severity of HF. AIMS: To determine the influence of AF on mortality of HF patients distinguishing between patients with preserved and deteriorated systolic function (SF). METHOD AND RESULTS: 1636 patients who, between 1991 and 2002 had been hospitalized in a Cardiology Service for HF, were studied. Survival (SV) data (mean follow-up time: 3.14 years) has shown that there was no difference in SV between patients with (540 patients of the whole group) and without AF in the group with preserved SF (presented in 38.7% of cases), however, in the group of patients with deteriorated SF (AF presented in 31.0% of cases), SV time was significantly (p=0.01) shorter among patients with AF, this association being independent of age, sex, aetiology, risk factors, clinical signs and pharmacological treatment; relative risk: 1.831(1.120-2.994). CONCLUSION: AF is more prevalent among HF patients with preserved SF than among those with deteriorated SF, but only increases the risk of death among the latter.

Long-term improvement of QT dispersion is unaffected by short-term changes in blood pressure during treatment of systemic hypertension with enalapril.

BACKGROUND: We report the reduction of QT and QTc dispersion in patients treated for 7 years with enalapril for systemic hypertension with left ventricular (LV) hypertrophy. We assess the correlation between QT dispersion and LV mass during this period and at the end of an 8-week period of suspension of enalapril treatment after 5 years. METHODS: Twenty-four previously untreated patients with this condition took enalapril (20 mg twice daily) for 7 years, except during an 8-week period following 5-year follow-up. Cardiovascular parameters were determined by two-dimensional guided M-mode echocardiography, and QT interval was measured, in a pretreatment placebo phase, 8 weeks and 1, 3, 5, and 7 years after the start of the therapy, at the end of the 8-week suspension effected after 5 years, and 8 weeks after the end of the suspension. RESULTS: Therapy rapidly reduced blood pressure (BP) from 156/105 mmHg to normal values: 134/84 mmHg after 8 weeks' treatment, 130-84 mmHg at 7-year follow-up (P < 0.001 with respect to the placebo phase). LV mass index decreased progressively until at 5-year follow-up the reduction had reached 39% (P < 0.001), after which neither LV mass nor any other structural parameter underwent any further significant change. During this time, QT dispersion (DeltaQT) and the dispersion of "corrected" QT (DeltaQTc) decreased significantly: DeltaQT (from 61 +/- 21 to 37 +/- 13 ms) and DeltaQTc (from 67 +/- 27 to 41 +/- 16 ms). After suspension of treatment for 8 weeks following 5-year follow-up, DeltaQT was 40 +/- 14 ms and DeltaQTc was 44 +/- 17 ms; there were no significant changes either in DeltaQT and DeltaQTc or LV hypertrophy although BP had returned to pretreatment values (BP: 150 +/- 16; 101 +/- 10 mmHg). CONCLUSIONS: Long-term enalapril treatment of hypertensive patients with LV hypertrophy induces marked regression of LV mass and improvement of QT dispersion. These improvements occur on a longer timescale than improvement in BP, and are not affected by transient changes in BP values.