Jean-Marie Fauvel

Prognostic Value of Heart Rate Variability in Time Domain Analysis in Congestive Heart Failure

AbstractAims: Analysis of heart rate variability is a noninvasive tool that allows to study autonomic control of the heart. Several studies have shown disturbed heart rate variability in patients with chronic heart failure (CHF). We sought to assess the prognostic value of time domain measures of heart rate variability in CHF. Methods and Results: We prospectively enrolled 190 patients with CHF in sinus rhythm, mean age 61±12 years, 109 (57.4 %) in NYHA class II and 81 (42.6 %) in class III or IV, mean cardiothoracic ratio 57.6±6.4 % and mean left ventricular ejection fraction 28.2±8.8 %, 85 (45 %) with ischemic and 105 (55 %) with idiopathic dilated cardiomyopathy. Time domain measures of heart rate variability were obtained from 24[emsp4 ]h Holter ECG recordings. During follow-up (22±18 months), 55 patients died. In multivariate analysis, independent predictors for all-cause mortality were: ischemic heart disease, cardiothoracic ratio ≥60 % and standard deviation of all normal RR intervals <67[emsp4 ]ms (RR=2.5, 95 % CI 1.5–4.2). Conclusions: Depressed heart rate variability has independent prognostic value in patients with CHF.

Radio-Frequency Ablation of Atrial Flutter: Long-Term Results and Predictive Value of Cavo-Tricuspid Isthmus Bidirectional Block as Determined by a Simplified Technique

Objectives: Complete bidirectional cavo-tricuspid isthmus (CTI) block is mandatory for radio-frequency (RF) ablation of typical atrial flutter (AF). CTI block can be assessed by a simplified method using two catheters and the technique of differential pacing, but long-term results in large series are poorly known. Methods: CTI RF ablation was performed in 255 consecutive patients with typical AF, using one quadripolar catheter, and the ablation catheter, in association with the technique of differential pacing. Results: Procedural success, as defined by documentation of complete bidirectional CTI block using limited activation mapping, positive differential pacing together with termination of ongoing AF, was achieved in 80% of patients. AF recurred in 37 patients (14%) over a mean follow-up period of 15 ± 9 months. Two hundred and forty-one patients (94%) were finally cured, with 1.1 procedures/patient. The recurrence rate was related to the achievement of complete CTI bidirectional block (12% vs. 29%, p = 0.01). Conclusions: Long-term results of CTI ablation, employing a simplified method using the differential pacing technique, are similar to those for the standard methods using multipolar catheters. Therefore, this technique compares favorably to other established methods for such common RF procedures, especially due to its lower cost.

Gender disparity in 48-hour mortality is limited to emergency percutaneous coronary intervention for ST-elevation myocardial infarction

BACKGROUND Previous studies indicate that mortality from acute coronary syndromes is higher in women than in men, especially in case of interventional strategy. AIM To assess whether the in-hospital mortality rate differs between genders during the first 48h after emergency percutaneous coronary intervention for ST-elevation myocardial infarction (emergency PCI-STEMI) or after non-emergency PCI. METHODS All patients treated with PCI between January 2005 and June 2008 were included. The primary endpoint was frequency of death within 48h after the PCI procedure; secondary endpoints included frequency of recurrent myocardial infarction, new PCI or coronary artery bypass graft surgery, stroke, and major vascular or renal complications. Data were analysed via logistic regression with and without propensity-score matching. RESULTS More than 9000 patients underwent PCI. In the emergency PCI-STEMI group (n=1753), 48-hour mortality occurred in 2.2% of men and 4.9% of women (p=0.004). However, gender disparity occurred only in elderly patients; the rate was significantly (p=0.02) higher in women (8.1%) than in men (3.3%) aged > or =75 years. There was no evidence of gender disparity in the non-emergency PCI group (n=7336) or in secondary endpoints for either PCI group. Similar results were obtained in pair analyses of men and women with matching propensity scores. CONCLUSIONS Elderly women have a disproportionately high in-hospital mortality rate during the first 48h after emergency PCI for treatment of STEMI; however, there is no gender discrepancy in younger patients or patients of any age who receive non-emergency procedures.

Slower heart rate and altered rate dependence of ventricular repolarization in patients with lone atrial fibrillation

BACKGROUND Electrophysiological alterations in atrial fibrillation (AF) may be genetically based and may lead to changes in ventricular repolarization. Short QT syndrome is a rare channelopathy with abbreviated ventricular repolarization and a propensity for AF. AIMS To determine if minor unrecognized forms of short QT syndrome can explain some cases of lone AF. METHODS We prospectively compared QT intervals in 66 patients with idiopathic lone AF and 132 age- and sex-matched controls. QT intervals were measured during sinus rhythm in each of the 12 surface electrocardiogram leads and corrected using Bazetts formula (QTc). QT intervals were also corrected using other formulae. Uncorrected QT and heart rate regression lines were compared between AF patients and controls. RESULTS AF patients presented with a slower resting heart rate (64 ± 10 beats per minute [bpm] vs 69 ± 9 bpm; P=0.0006). QTc intervals were shorter in AF patients in 11/12 electrocardiogram leads (significant in 7/12, borderline in 2/12; mean QTc 381 ± 21 ms vs 388 ± 22 ms; P=0.02). QTc intervals were also shorter in AF patients, significantly or not, using other correction formulae. For similar heart rates, uncorrected QT intervals were shorter in patients when heart rates were greater than 70 bpm and longer when heart rates were less than 60 bpm. AF patients displayed steeper QT/heart rate regression line slopes than controls (P=0.009). CONCLUSION Heart rate is significantly slower and the rate dependence of ventricular repolarization is significantly altered in patients with lone AF compared with controls. Further study is warranted to determine if AF induces subsequent ventricular repolarization changes or if these modifications are caused by an underlying primary electrical disease.

Prognostic value of ventricular arrhythmias in hypertensive patients

OBJECTIVE Hypertensive left ventricular hypertrophy (LVH) is associated with increased risk of arrhythmias and mortality. However, no clinical study demonstrated a significant relation between ventricular arrhythmias and mortality in systemic hypertension. DESIGN AND METHODS To evaluate the prognostic value of arrhythmogenic markers in systemic hypertension, we included between 1987 and 1993. 214 hypertensive patients, 59.1 +/- 12.8 years old, without symptomatic coronary disease, myocardial infarction, systolic dysfunction, electrolyte disturbances or antiarrhythmic therapy. At inclusion, an ECG, a 24 h Holter ECG (204 patients) with Lown classification of ventricular arrhythmias, an echocardiography (reliable in 187 patients) with left ventricular mass index and ejection fraction calculation, a SAECG (125 patients, enrolled after 1988) with ventricular late potentials (LP) were recorded. QT interval dispersion (QTd) was calculated on 12 leads standard ECG and LVH was appreciated. RESULTS At baseline echocardiographic LVH was recorded in 63 patients (33.7%) with normal ejection fraction (75 +/- 7.4%). Non-sustained ventricular tachycardia (Lown IVb) was found in 33 pts (16.2%) and LP in 27 patients (21.6%). After a mean follow up of 42.4 +/- 26.8 months, all-cause mortality was 11.2% (24 patients); 17 patients died of cardiac causes (7.9%); of these 9 patients (4.2%) died suddenly. In univariate analysis, age, strain pattern of LVH, advanced Lown classes and abnormal QT dispersion (> 80 ms) were significantly related to global, cardiac and sudden death (p < or = 0.01). Left ventricular mass index was closely related to cardiac mortality (p = 0.002). LP failed to predict mortality. In multivariate analysis, only Lown class IVb was an independent predictor of global and cardiac mortality, increasing the risk of global death 2.6 fold [1.2-6.0] (CI 95%) and the risk of cardiac death 3.5 fold [1.2-9.7] (CI 95%). CONCLUSIONS In hypertensive patients the presence of non-sustained ventricular tachycardia on 24 h Holter has a prognostic value.