Roberto Maestri

Short-Term Heart Rate Variability Strongly Predicts Sudden Cardiac Death in Chronic Heart Failure Patients

Background—The predictive value of heart rate variability (HRV) in chronic heart failure (CHF) has never been tested in a comprehensive multivariate model using short-term laboratory recordings designed to avoid the confounding effects of respiration and behavioral factors. Methods and Results—A multivariate survival model for the identification of sudden (presumably arrhythmic) death was developed with data from 202 consecutive patients referred between 1991 and 1995 with moderate to severe CHF (age 52±9 years, left ventricular ejection fraction 24±7%, New York Heart Association class 2.3±0.7; the derivation sample). Time- and frequency-domain HRV parameters obtained from an 8′ recording of ECG at baseline and during controlled breathing (12 to 15 breaths/min) were challenged against clinical and functional parameters. This model was then validated in 242 consecutive patients referred between 1996 and 2001 (validation sample). In the derivation sample, sudden death was independently predicted by a model that included low-frequency power (LFP) of HRV during controlled breathing ≤13 ms2 and left ventricular end-diastolic diameter ≥77 mm (relative risk [RR] 3.7, 95% CI 1.5 to 9.3, and RR 2.6, 95% CI 1.0 to 6.3, respectively). The derivation model was also a significant predictor in the validation sample (P =0.04). In the validation sample, LFP ≤11 ms2 during controlled breathing and ≥83 ventricular premature contractions per hour on Holter monitoring were both independent predictors of sudden death (RR 3.0, 95% CI 1.2 to 7.6, and RR 3.7, 95% CI 1.5 to 9.0, respectively). Conclusions—Reduced short-term LFP during controlled breathing is a powerful predictor of sudden death in patients with CHF that is independent of many other variables. These results refine the identification of patients who may benefit from prophylactic implantation of a cardiac defibrillator.

Arterial Baroreflex Modulation of Heart Rate in Chronic Heart Failure: Clinical and Hemodynamic Correlates and Prognostic Implications

BACKGROUND In chronic heart failure (CHF), arterial baroreflex regulation of cardiac function is impaired, leading to a reduction in the tonic restraining influence on the sympathetic nervous system. Because baroreflex sensitivity (BRS), as assessed by the phenylephrine technique, significantly contributes to postinfarction risk stratification, the aim of the present study was to evaluate whether in CHF patients a depressed BRS is associated with a worse clinical hemodynamic status and unfavorable outcome. METHODS AND RESULTS BRS was assessed in 282 CHF patients in sinus rhythm receiving stable medical therapy (age, 52+/-9 years; New York Heart Association [NYHA] class, 2.4+/-0.6; left ventricular ejection fraction [LVEF], 23+/-6%). The BRS of the entire population averaged 3.9+/-4.0 ms/mm Hg (mean+/-SD) and was significantly related to LVEF and hemodynamic parameters (LVEF, P<.005; cardiac index and pulmonary wedge pressure, P<.001 by regression analysis). Patients in NYHA classes III or IV and those with severe mitral regurgitation had markedly depressed vagal reflexes. The association of BRS with survival was described after its categorization in three groups: below the lowest quartile (<1.3 ms/mm Hg), between the lowest quartile and the median (1.3 to 3 ms/mm Hg), and above the median (>3 ms/mm Hg). During a mean follow-up of 15+/-12 months, 78 primary events (cardiac death, nonfatal cardiac arrest, and status 1 priority transplantation) occurred (27.6%). BRS was significantly related to outcome (log rank, 9.1; P<.01), with a relative risk of 2.7 (95% confidence interval, 1.6 to 4.7) for patients with the major derangement in BRS (<1.3 ms/mm Hg). At multivariate analysis, BRS was an independent predictor of death after adjustment for noninvasive known risk factors but not when hemodynamic indexes were also considered. In CHF patients with severe mitral regurgitation, however, BRS remained a strong prognostic marker independent of hemodynamic function. CONCLUSIONS In moderate to severe CHF, a depressed sensitivity of vagal reflexes parallels the deterioration of clinical and hemodynamic status and is significantly associated with poor survival. Particularly in patients with severe mitral regurgitation the baroreceptor modulation of heart rate provides prognostic information of incremental value to hemodynamic parameters.

Cost/utility ratio in chronic heart failure: comparison between heart failure management program delivered by day-hospital and usual care

OBJECTIVES This study compared the effectiveness and cost/utility ratio between a heart failure (HF) management program delivered by day-hospital (DH) and usual care in chronic heart failure (CHF) outpatients. BACKGROUND Previous studies showed that about 50% of readmissions for CHF can be prevented by a multidisciplinary approach However, the performance, effectiveness, and cost/utility ratio of a process of HF outpatient management related to evidence-based medicine have not been considered. METHODS A total of 234 prospective patients discharged by a HF Unit were randomized to two management strategies: 122 patients to usual community care and 112 patients to a HF management program delivered by the DH. Management (rate of readmissions, therapeutic interventions), functional parameters (New York Heart Association [NYHA] functional class, left ventricular diameters, and ejection fraction, deceleration time of early diastolic mitral flow, peak oxygen uptake, and mitral regurgitation) and hard outcomes (cardiac death and urgent cardiac transplantation) were evaluated. The cost/utility ratios of the two strategies were compared. RESULTS After 12 3 months of follow-up, the individual rate access in DH was 5.5 3.8 days. The DH subjects were readmitted to the hospital less frequently than were the usual-care group patients (13 vs. 78, p 0.00001). Patients allocated to usual-care management showed heterogeneous changes in NYHA functional class (13% improved and 16% worsened p NS); In contrast, the DH group showed significant changes in NYHA functional class (23% improved and 11% worsened, p 0.009). Hard cardiac events in the one-year follow-up occurred in 25/234 (10.6%) patients; cardiac death occurred in 21/122 (17.2%) of the community group and in 3/112 (2.7%) in the DH group (p 0.0007). One DH patient underwent urgent transplantation. Comparison of the two managerial models by Cox regression analysis showed that DH management significantly protected against the appearance of hard events (relative risk [RR] 0.17; confidence interval [CI] 0.06 to 0.66). The cost/utility ratio of the two management strategies was similar (usual care

Rehabilitation treatment of gait in patients with Parkinson's disease with freezing: A comparison between two physical therapy protocols using visual and auditory cues with or without treadmill training

2,409 vs. DH

Nonselective beta-adrenergic blocking agent, carvedilol, improves arterial baroflex gain and heart rate variability in patients with stable chronic heart failure

2,244). The incremental analysis revealed a cost savings of

Surrogate data analysis for assessing the significance of the coherence function

1,068 for each quality-adjusted life year gained. The cost/utility ratio for the integration of DH management of CHF was

Clinical impact of evaluation of cardiovascular control by novel methods of heart rate dynamics.

19,462 (CI

Home telemonitoring in heart failure patients: the HHH study (Home or Hospital in Heart Failure).

13,904 to

Prognostic implications of baroreflex sensitivity in heart failure patients in the beta-blocking era.

34,048). CONCLUSIONS A heart failure outpatient management program delivered by a DH can reduce mortality and morbidity of CHF patients. This management strategy is cost-effective and has an equitable value from a societal point of view. (J Am Coll Cardiol 2002;40:1259 ‐ 66)

Scopolamine improves autonomic balance in advanced congestive heart failure.

Freezing is a disabling symptom in patients with Parkinsons disease. We investigated the effectiveness of a new rehabilitation strategy based on treadmill training associated with auditory and visual cues. Forty Parkinsonian patients with freezing were randomly assigned to two groups: Group 1 underwent a rehabilitation program based on treadmill training associated with auditory and visual cues, while Group 2 followed a rehabilitation protocol using cues and not associated with treadmill. Functional evaluation was based on the Unified Parkinsons Disease Rating Scale Motor Section (UPDRS III), Freezing of Gait Questionnaire (FOGQ), 6‐minute walking test (6MWT), gait speed, and stride cycle. Patients in both the groups had significant improvements in all variables considered by the end of the rehabilitation program (all P = 0.0001). Patients treated with the protocol including treadmill, had more improvement than patients in Group 2 in most functional indicators (P = 0.007, P = 0.0004, P = 0.0126, and P = 0.0263 for FOGQ, 6MWT, gait speed, stride cycle, respectively). The most striking result was obtained for 6MWT, with a mean increase of 130 m in Group 1 compared with 57 m in Group 2. Our results suggest that treadmill training associated with auditory and visual cues might give better results than more conventional treatments. Treadmill training probably acts as a supplementary external cue.