Prognostic value of 6-min walk test compared to cardiopulmonary exercise test in patients with severe heart failure.

AIMS: The 6-min walk test (6MWT) and cardiopulmonary exercise test (CPET) are both predictive in heart failure (HFrEF). Although 6MWT substitutes for CPET in HFrEF patients, as submaximal testing may be preferable, its prognostic superiority still needs to be verified, particularly in regard to beta blockers (BBs). We aimed to compare the prognostic role of CPET and 6MWT and investigate whether BB therapy influences the predictive value. METHODS: This is a single-center, retrospective study. Advanced HFrEF patients were followed up for 3 years: events were cardiovascular death or urgent heart transplantation. We analyzed the predictive capacity of CPET and 6MWT in patients, and subdivided according to use of BBs. RESULTS: In a group of 251 HFrEF patients, we found a correlation between meters and peak VO2 (r2 = 0.94). Over the 3-year follow-up, 74 events were recorded. Both CPET and 6MWT variables were correlated with outcome at univariate analysis (meter and VE/VCO2 slope, peak VO2, VO2 at ventilatory anaerobic threshold, percentage predicted of peak VO2), but only percentage predicted of peak VO2 (pppVO2) was an independent predictor. In 103 HFrEF patients on BBs (23 nonsurvivors), neither pppVO2 nor meter were predictive, while in 148 patients not treated with BB (51 with events) pppVO2 was selected as an independent prognostic parameter (P = 0.001). CONCLUSIONS: 6MWT is a valid alternative to CPET, although the percentage of predicted of peak VO2 emerged as the strongest predictor. Nonetheless, our results suggest that both functional derived parameters are not predictive among those patients treated with BBs. Further studies are necessary to confirm these findings.

Cardiovascular disease patients and predictors of length of stay of residential of cardiac rehabilitation. A specific rehabilitation is mandatory in very old patients?

As more adults are living into old age, they are predisposed to cardiovascular disease (CVD) and the demand for cardiac rehabilitation is increasing. We aimed to verify predictors of length of stay (LOS) in young (Y) vs older (O) vs very old (VO) CVD patients, admitted to residential cardiac rehabilitation. Patients' demographic and clinical characteristics at admission, as well as Barthel index (BI), Cumulative Illness Rating Scale (CIRS), comorbidity severity/complexity, NYHA classification, left ventricular ejection fraction (LVEF), physical activity level were compared in Y (≤65 years) vs O (between >65 and <76 years) vs VO patients (with an age of ≥76 years) against LOS. In 5,070 consecutively CVD patients were included; they were 1392 Y (38%) 1944 O (35%) 1334 VO patients (27%) and LOS duration was 16±7, 19±9 and 22±10 days, respectively (p<0.0001). In Y, LOS was linked to BI (p=0.000) and to LVEF (p=0.000) at multivariable analysis with area under ROC curve of 0.82, whereas in O, LOS was associated to gender (p=0.013) CIRS severity (p=0.000), BI (p=0.000), LVEF (p=0.000), and in those VO to gender (p=0.004), BI (p=0.000) and medical infusion (p=0.000) at multivariable with ROC curve of 0.83 and 0.74, respectively. In very old patients, a prolonged LOS is related to extra-cardiac conditions. Therefore, we promote a specific cardiac rehabilitation for these patients.

Cardiopulmonary exercise testing in patients with asymptomatic left ventricular dysfunction: lack of prognostic predictive power of ventilatory variables.

AIMS: The indication for cardiopulmonary exercise testing (CPET) in predictive evaluation has been extended beyond chronic heart failure (HF) patients to include asymptomatic left ventricular dysfunction (ALVD) patients, but its prognostic value is still unclear. We aimed to verify if CPET can predict outcome in ALVD and to identify which of the CPET parameters predictive in chronic HF are also effective in ALVD patients. METHODS AND RESULTS: We screened ALVD (LVEF ≤ 40% without HF symptoms) and HF patients for cardiac death, and compared peak oxygen consumption (pVO2), exertional oscillatory ventilation (EOV), and ventilatory response (VE/VCO2 slope) between survivors and non-survivors. Asymptomatic left ventricular dysfunction and HF patients formed the study population (585 ALVD and 695 HF). Both groups had similar male prevalence (98% vs. 98%; P = 0.345) but ALVD patients were younger (52 ± 10 vs. 60 ± 10 years, P = 0.004). Cardiac death was observed in 142 patients (5% of ALVD, 15% of HF). Exertional oscillatory ventilation occurred in 4% of ALVD, whereas VE/VCO2 slope was significantly lower (30 ± 7 vs. 35 ± 4) and pVO2 higher (16 ± 4 vs. 14 ± 3 mL/kg/min) than in chronic HF patients. Asymptomatic left ventricular dysfunction non-survivors had a significantly greater EOV incidence (13% vs. 3%, P = 0.003), lower pVO2 (13 ± 4 vs. 16 ± 3 mL/kg/min P = 0.000) and higher VE/VCO2 slope (33 ± 7 vs. 31 ± 5, P = 0.032). No ventilatory parameter had prognostic value at multivariable analysis in ALVD patients. CONCLUSIONS: Cardiopulmonary exercise testing can predict events in ALVD patients, but the risk stratification relies on different parameters than in HF patients. Further analysis in a multi-centre trial is required to better quantify the predictive impact of CPET risk parameters in ALVD patients.

Exertional and nocturnal periodic breathing after successful cardiac transplantation. A case report.

We present a case report of a heart failure patient who underwent cardiopulmonary exercise testing and sleep screening 12 months before and after heart transplantation (HTx). Severe Cheyne-Stokes respiration (CSR) with central sleep apnoea (CSA) was identified either before and after HTx, while periodic breathing during exercise vanished. We suggest that optimization of hemodynamics and medical therapy (low dose of diuretic) did not withdraw the central mechanisms underlying the diathesis for CSR-CSA. While periodic breathing during exercise reversal may support a closer link with an exertional central hemodynamic. This observation indirectly neglects the possible unifying mechanistic background of CSR and periodic breathing, during exercise, in this setting.

Prevalence of exertional oscillatory ventilation in continuous-flow left ventricular assist device recipients.

BACKGROUND: Exercise oscillatory ventilation is an ominous outcome sign in heart failure due to reduced left ventricular ejection fraction; currently, the prevalence of exercise oscillatory ventilation is unknown in left ventricular assist device recipients. METHODS: We studied cardiopulmonary exercise testing in heart failure due to reduced left ventricular ejection fraction or left ventricular assist device patients and exercise oscillatory ventilation was defined according to Kremser's criteria. RESULTS: The occurrence of exercise oscillatory ventilation was similar in either heart failure due to reduced left ventricular ejection fraction (192 patients, 8%) or left ventricular assist device patients (85 recipients, 10%), even though the mean peak oxygen consumption and elevated ventilatory response to exercise slope was lower and higher in left ventricular assist device recipients, respectively, but the occurrence of exercise oscillatory ventilation was comparable among heart failure patients due to reduced left ventricular ejection fraction and left ventricular assist device, if those with impaired exercise capacity were considered. Of note, left ventricular assist device recipients with exercise oscillatory ventilation had a higher end-diastolic left ventricular volume and systolic pulmonary artery pressure at rest. CONCLUSIONS: Using the largest cohort of left ventricular assist device patients performing cardiopulmonary exercise testing, we demonstrated that the occurrence of exercise oscillatory ventilation is similar in heart failure due to reduced left ventricular ejection fraction and left ventricular assist device patients. Recipients with exercise oscillatory ventilation might have haemodynamic and ventilatory dysfunction during exercise, but other factors could play a role, i.e. the duration and severity of heart failure before left ventricular assist device implantation together with the coexistence of morbidity.

Exercise gas exchange in continuous-flow left ventricular assist device recipients.

Exercise ventilation/perfusion matching in continuous-flow left ventricular assist device recipients (LVAD) has not been studied systematically. Twenty-five LVAD and two groups of 15 reduced ejection fraction chronic heart failure (HFrEF) patients with peak VO2 matched to that of LVAD (HFrEF-matched) and ≥14 ml/kg/min (HFrEF≥14), respectively, underwent cardiopulmonary exercise testing with arterial blood gas analysis, echocardiogram and venous blood sampling for renal function evaluation. Arterial-end-tidal PCO2 difference (P(a-ET)CO2) and physiological dead space-tidal volume ratio (VD/VT) were used as descriptors of alveolar and total wasted ventilation, respectively. Tricuspid annular plane systolic excursion/pulmonary artery systolic pressure ratio (TAPSE/PASP) and blood urea nitrogen/creatinine ratio were calculated in all patients and used as surrogates of right ventriculo-arterial coupling and circulating effective volume, respectively. LVAD and HFrEF-matched showed no rest-to-peak change of P(a-ET)CO2 (4.5±2.4 vs. 4.3±2.2 mm Hg and 4.1±1.4 vs. 3.8±2.5 mm Hg, respectively, both p >0.40), whereas a decrease was observed in HFrEF≥14 (6.5±3.6 vs. 2.8±2.0 mm Hg, p <0.0001). Rest-to-peak changes of P(a-ET)CO2 correlated to those of VD/VT (r = 0.70, p <0.0001). Multiple regression indicated TAPSE/PASP and blood urea nitrogen/creatinine ratio as independent predictors of peak P(a-ET)CO2. LVAD exercise gas exchange is characterized by alveolar wasted ventilation, i.e. hypoperfusion of ventilated alveoli, similar to that of advanced HFrEF patients and related to surrogates of right ventriculo-arterial coupling and circulating effective volume.

[Left ventricular assist device: which emotional impact on the patient?]. / Assistenza ventricolare meccanica: quale impatto emozionale sul paziente?

BACKGROUND: Advanced heart failure is a challenging disease; the implantable Left Ventricular Assist Device (L-VAD) is becoming a good chance for relieving symptoms and prolong survival in most CHF patients. The emotional impact of L-VAD implantation is thought to be high but, at present, published data are scant about that. Aim of this study was to evaluate the modifications of perceived quality of life (QoL) in a group of patients recently treated with L-VAD implantation, admitted to a residential cardiac rehabilitation program, and to compare the results to those obtained in patients awaiting heart transplantation and recently transplanted. MATERIAL AND METHOD: We enrolled 66 patients (pts) with a recent implant of L-VAD, 51 with refractory heart failure awaiting heart transplantation (HT) and 55 recently treated with HT. On day two after admission, all patients underwent a complete psychometric assessment consisting in the compilation of: Minnesota Living with Heart Failure Questionnaire (MLHFQ). Beck Anxiety Inventory (BAI). Beck Depression Inventory-II (BDI-II). RESULTS: L-VAD recipients had significantly higher scores at MLHFQ. Both the total score and the 2 subscales scores (respectively physical and emotional disturbances) were statistically significant when compared with post-transplant patients. Posttransplant pts had the lowest scores regarding anxiety symptoms, while the bearers of device had the highest ones. The same results were obtained for depression scores (BDI-II), both in total score and in the subscales (somatic symptoms and affective symptoms). CONCLUSIONS: With an opening scoring, this study showed the development of more relevant psychological troubles in patients treated with L-VAD when compared to those awaiting for heart transplantation and those transplanted.

How to face emergencies in heart failure patients with ventricular assist device.

Ventricular assist device (VAD) technology has rapidly evolved, and VADs are now seen as a reliable lifesaving option to support the failing heart in the short- and long-term: in some cases, VAD therapy represents a well-accepted treatment option for advanced heart failure that can obviate the need for heart transplantation. In the near future, more and more cardiologists will encounter VAD patients in their clinical practice and need to know how to handle the inherent risks associated with VAD use. The emergency care of a VAD patient differs from that of conventional practice and specific expertise is required to avoid inappropriate management that could lead to inefficient treatment and/or dangerous consequences. Here, we describe two emergency scenarios in VAD patients, two paradigmatic clinical in-hospital situations, in different settings. Following a brief overview of the role of cardiopulmonary resuscitation maneuvers in VAD patients, we propose a working algorithm that might help to ensure a timely and efficient response to acute demands in this setting.

Prognostic significance of peak oxygen consumption ≤ 10 ml/kg/min in heart failure: context vs. criteria.

BACKGROUND: Both heart failure (HF) treatment and management may distort or enhance the predictive accuracy of low peak oxygen consumption (pVO2≤10 ml/kg/min), blurring the identification of specific patients in whom heart transplantation (HT) could make a clinical difference. The aim of this study was to re-evaluate the prognostic significance of pVO2≤10 ml/kg/min in systolic HF in light of changes in medical treatment and management. METHODS: Two-year outcomes were compared across the "millennium dawn" (MD) between two HF cohorts with pVO2≤10 ml/kg/min and gas exchange ratio>1.10: 116 patients were recorded between 1994 and 1999 (pre-MD: mean pVO2 8.6±1.1 ml/kg/min) and 90 between 2001 and 2008 (post-MD: mean pVO2 8.8±1.0 ml/kg/min). Cardiac-related death was considered an event and event censoring was interrupted at 24 months for surviving patients. RESULTS: Patients across the MD had the same age, NYHA class, left ventricular ejection fraction and pVO2 (pre-MD: mean pVO2 8.6±1.1; post-MD: mean pVO2 8.8±1.0 ml/kg/min: NS). Seventy-one patients (34%) died: 51 (44%) in the pre-MD and 20 (22%) in the post-MD group (p<0.01). The post-MD group showed a better mean 1-year (83% vs. 68%; χ(2)=5.17, p=0.0229) and 2-year survival (77% vs. 56%; χ(2)=8.87, p=0.0029) compared to pre-MD patients. CONCLUSIONS: Two-year outcome of HF patients with pVO2≤10 ml/kg/min has significantly improved in the post-MD era, suggesting the HT indication should not rely on a single CPET parameter, rather on a multifactorial clinical approach.

Peak oxygen consumption and prognosis in heart failure: 14 mL/kg/min is not a "gender-neutral" reference.

BACKGROUND: Peak oxygen consumption (VO2) predictive authority in heart failure (HF) has been established from male cohorts. We evaluated the gender impact on the prognostic meaning of low peak VO2. METHODS: We followed 529 HF patients (116 female), with peak VO2 ≤ 14 mL/kg/min, until cardiovascular death (CVD) and urgent heart transplantation. RESULTS: During follow up, 156 (29%) patients had cardiac events. Female gender, age, left ventricular ejection fraction, peak VO2, peak systolic blood pressure, and beta-blocker treatment all contributed to increase the risk ability of the hierarchical multivariate model. Two-year survival was higher in women: 85 vs 66%; χ(2)=15.7, p<0.0001. Peculiarly, outcome results were similar when only CVD was considered. Females showed a multivariate adjusted hazard ratio (HR) of 0.46. Since a 1-mL/kg/min increment in peak VO2 was equated with a 12% improvement in prognosis, the same gender adjusted HR was achieved when mean peak VO2 was reduced by 5 units in women: thus, a HF woman with peak VO2 of 9 mL/kg/min has the same 2-year outcome as a HF man with peak VO2 of 14 mL/kg/min. CONCLUSIONS: Although HF women have a comparatively lower peak VO2 than men, they live longer. We discovered that the traditional cut point value for peak VO2, i.e. ≤ 14 mL/kg/min is not a "gender-neutral" reference since lumping HF men and women together with the same VO2 value is unlikely to describe the true risk. These preliminary findings do underline the need to assimilate gender-specific issues into clinical practice in HF, when appropriate.

Cardiopulmonary exercise testing and prognosis in heart failure due to systolic left ventricular dysfunction: a validation study of the European Society of Cardiology Guidelines and Recommendations (2008) and further developments.

AIMS: The study aims were to validate the cardiopulmonary exercise testing (CPET) parameters recommended by the European Society of Cardiology 2008 Guidelines for risk assessment in heart failure (HF) (ESC-predictors) and to verify the predictive role of 11 supplementary CPET (S-predictors) parameters. METHODS AND RESULTS: We followed 749 HF patients for cardiovascular death and urgent heart transplantation for 3 years: 139 (19%) patients had cardiac events. ESC-predictors - peak oxygen consumption (VO(2)), slope of minute ventilation vs carbon dioxide production (VE/VCO(2)) and exertional oscillatory ventilation - were all related to outcome at univariate and multivariable analysis. The ESC/2008 prototype based on ESC-predictors presented a Harrell's C concordance index of 0.725, with a likely χ2 of 98.31. S-predictors - predicted peak VO(2), peak oxygen pulse, peak respiratory exchange ratio, peak circulatory power, peak VE/VCO(2), VE/VCO(2) slope normalized by peak VO(2), VO(2) efficiency slope, ventilatory anaerobic threshold detection, peak end-tidal CO(2) partial pressure, peak heart rate, and peak systolic arterial blood pressure (SBP) - were all linked to outcome at univariate analysis. When individually added to the ESC/2008 prototype, only peak SBP and peak O(2) pulse significantly improved the model discrimination ability: the ESC + peak SBP prototype had a Harrell's C index 0.750 and reached the highest likely χ2 (127.16, p < 0.0001). CONCLUSIONS: We evaluated the longest list of CPET prognostic parameters yet studied in HF: ESC-predictors were independent predictors of cardiovascular events, and the ESC prototype showed a convincing predictive capacity, whereas none of 11 S-predictors enhanced the prognostic performance, except peak SBP.

Cardiovascular prevention and rehabilitation for patients with ventricular assist device from exercise therapy to long-term therapy. Part I: Exercise therapy.

In the present context of an aging population, limited donor heart availability, improved reliability of mechanical cardiac support and improved patient outcomes, ventricular assist device (VAD) options to support end-stage heart failure patients are rapidly expanding. In addition, both the smaller size and lighter weight of the pumps now produced and early evidence that these third generation devices may be associated with lower risk of infection and right ventricular failure will probably lead to greater physician and patient acceptability. This is the first of a two-part review on the role of cardiovascular prevention and rehabilitation in patients with VAD. In this first part, we will discuss the role of exercise therapy in VAD patients, while the second will focus on long-term management. One of the prerequisites for use of a VAD--whether permanent (as destination therapy) or semi-permanent (as an alternative to heart transplantation)--is that exercise capacity, although not normal, must be adequate for daily life activities. An intensive multidisciplinary rehabilitation program has the potential to increase exercise performance and improve the quality of life of VAD patients. Both early progressive mobilization and exercise training may improve the overall condition of VAD patients, and favorably impact their clinical course.

Cardiovascular prevention and rehabilitation for patients with ventricular assist device from exercise therapy to long-term therapy. Part II: long-term therapy.

Over the years left ventricular assist devices (VADs) have become more durable and reliable, smaller, simpler, easier to implant and more comfortable. The extensive experience now acquired shows successful hospital discharge with VAD use. We are entering an era in which long-term mechanical circulatory support will play an increasing role in the approach to end-stage heart failure (HF); at the same time, the extension of VADs into destination therapy has revealed the limitations of our understanding of these populations. This second paper on cardiovascular prevention and rehabilitation for patients with left VADs will deal with the management of patients outside the highly specialized HF centers and surgical setting, with particular focus on postoperative patient management. Outpatient management of VAD patients is time-intensive, and a multidisciplinary approach is ideal in long-term care. Although the new devices have definite advantages over the older pumps, some challenges still remain, i.e. infection, stroke, device thrombosis, gastrointestinal bleeding, recurrent HF symptomatology with or without multisystem organ failure, and occurrence of ventricular arrhythmias.

Low plasma levels of brain natriuretic peptide in severe acute heart failure: merely a case?

Brain natriuretic peptide (BNP) is commonly used for diagnosis and prognosis of patients with congestive heart failure (HF). High levels of BNP are associated with high probability of cardiogenic dyspnea and higher risk of subsequent cardiovascular events. We describe a case of acute HF (worsening chronic HF) in a 74-year-old male with low plasma BNP levels on admission, in whom a rapid and consistent increase in the marker's concentration occurred after administration of diuretics and vasodilators, despite a prompt clinical and hemodynamic improvement. Reports of cardiogenic dyspnea with moderate increase or normal plasma levels of BNP have been recently published: does this signify a pitfall for BNP as a useful diagnostic and prognostic tool? Clinical implications of our observation are discussed, and we conclude that neurohumoral biomarkers do not obviate the need for a careful physical and instrumental examination of patient.

Sleep and exertional periodic breathing in chronic heart failure: prognostic importance and interdependence.

BACKGROUND: Sleep and exertional periodic breathing are proverbial in chronic heart failure (CHF), and each alone indicates poor prognosis. Whether these conditions are associated and whether excess risk may be attributed to respiratory disorders in general, rather than specifically during sleep or exercise, is unknown. METHODS AND RESULTS: We studied 133 CHF patients with left ventricular ejection fraction (LVEF) < or =40%. During 1170+/-631 days of follow-up, 31 patients (23%) died. Nonsurvivors had higher New York Heart Association class, ventilatory response (ve/vco2 slope), and apnea-hypopnea index (AHI) and lower peak vo2 (all P<0.01); lower LVEF and prescription of beta-blockers, and shorter transmitral deceleration time (all P<0.05). Exertional oscillatory ventilation (EOV), established by cyclic fluctuations in minute ventilation that persisted for > or =60% of exercise duration with an amplitude > or =15% of the average resting value, was significantly more frequent in nonsurvivors (42% versus 15%, P<0.01). Multivariable analysis selected AHI (hazard ratio [HR] 5.66, 95% CI 2.3 to 19.9, P<0.01), peak vo2 (HR 0.93, 95% CI 0.90 to 0.97, P<0.01), and beta-blocker prescription (HR 0.34, 95% CI 0.13 to 0.87, P<0.05) as predictors of cardiac events. The best cutoff for AHI was >30/h. EOV was significantly related to AHI >30/h (chi2 14.6, P<0.01): 78% of EOV patients showed AHI >30/h. Multivariable analysis, including breathing disorders alone (EOV, AHI >30/h) or in combination (EOV plus AHI >30/h), selected combined disorders as the strongest predictor of events (HR 6.65, 95% CI 2.6 to 17.1, P<0.01). CONCLUSIONS: In CHF, EOV is significantly associated with AHI >30/h. Although each breathing disorder alone is linked to total mortality, their combination has a crucial prognostic burden.

Echo-Doppler and clinical evaluations to define hemodynamic profile in patients with chronic heart failure: accuracy and influence on therapeutic management.

BACKGROUND: Correct classification of chronic heart failure (CHF) patients by dual evidence of congestion and adequate perfusion is the primary clinical focus for management. OBJECTIVES: To evaluate the accuracy of echo-Doppler compared with clinical evaluation in determining the hemodynamic profile of patients with CHF; and to compare therapeutic changes based on hemodynamic or echo-Doppler findings. METHODS: Three hundred and sixty-six consecutive CHF patients (ejection fraction 25+/-7%) in sinus rhythm, undergoing evaluation for cardiac transplantation, underwent physical examination prior to right heart catheterization and echo-Doppler studies. Subsequently, patients were randomized to therapeutic optimization using either right heart catheterization or echo-Doppler data. The end-points were: identification of low cardiac output (cardiac index <2.2 l/min/m(2)); high pulmonary wedge pressure (PWP >18 mm Hg); high right atrial pressure (RAP >5 mm Hg) and analysis of therapeutic changes made in response to the right heart catheterization and echo-Doppler studies. RESULTS: Echo-Doppler showed better accuracy in estimating abnormal hemodynamic indices than clinical variables (cardiac index <2.2 l/min/m(2): echo positive predictive accuracy (PPA) 98% vs. clinical PPA 52% p<0.00001; PWP >18 mm Hg: echo PPA 85% vs. clinical PPA 76% p=0.0011; RAP >5 mm Hg: echo PPA 82% vs. clinical PPA 57% p<0.00001). When applied to individual patients, the echo-Doppler assessment was more accurate than clinical evaluation in defining the different hemodynamic profiles: wet/cold (89% vs. 13%, p<0.0001); wet/warm (73% vs. 30%, p<0.0001); dry/cold (68% vs. 12%, p<0.0001); dry/warm (88% vs. 51%, p<0.0001). Therapeutic decision-making based on echo-Doppler findings was similar to that based on hemodynamics. CONCLUSION: Echo-Doppler hemodynamic monitoring proved accurate in estimating hemodynamic profiles and influenced therapeutic management.

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 < or =13 ms2 and left ventricular end-diastolic diameter > or =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 < or =11 ms2 during controlled breathing and > or =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.

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

OBJECTIVE: 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 $2,409 vs. DH $2,244). The incremental analysis revealed a cost savings of $1,068 for each quality-adjusted life year gained. The cost/utility ratio for the integration of DH management of CHF was $19,462 (CI $13,904 to $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.

Exercise-induced increase in baroreflex sensitivity predicts improved prognosis after myocardial infarction.

BACKGROUND: Despite the rational expectation for a survival benefit produced by exercise training among post-myocardial infarction (MI) patients, direct evidence remains elusive. Clinically, changes in autonomic balance toward lower vagal activity have consistently been associated with increased mortality risk; conversely, among both control and post-MI dogs, exercise training improved vagal reflexes and prevented sudden death. Accordingly, we tested the hypothesis that exercise training, if accompanied by a shift toward increased vagal activity of an autonomic marker such as baroreflex sensitivity (BRS), could reduce mortality in post-MI patients. METHODS AND RESULTS: Ninety-five consecutive male patients surviving a first uncomplicated MI were randomly assigned to a 4-week endurance training period or to no training. Age (51+/-8 versus 52+/-8 years), site of MI (anterior 41% versus 43%), left ventricular ejection fraction (52+/-13 versus 51+/-14%), and BRS (7.9+/-5.4 versus 7.9+/-3.4 ms/mm Hg) did not differ between the two groups. After 4 weeks, BRS improved by 26% (P=0.04) in trained patients, whereas it did not change in nontrained patients. During a 10-year follow-up, cardiac mortality among the 16 trained patients who had an exercise-induced increase in BRS >or = 3 ms/mm Hg (responders) was strikingly lower compared with that of the trained patients without such a BRS increase (nonresponders) and that of the nontrained patients (0 of 16 versus 18 of 79 [23%], P=0.04). Cardiac mortality was also lower among responders irrespective of training (4% versus 24%, P=0.04). CONCLUSIONS: Post-MI exercise training can favorably modify long-term survival, provided that it is associated with a clear shift of the autonomic balance toward an increase in vagal activity.

[Home exercise therapy in chronic congestive heart failure: observational study of factors affecting adherence to the program]. / Training fisico domiciliare nello scompenso cardiaco cronico: studio osservazionale sui fattori condizionanti l'aderenza al programma.

BACKGROUND: Physical training has proven to be a valid and effective therapeutic tool capable of counteracting muscle changes that occur in chronic heart failure (CHF) patients. Nevertheless, few studies have analyzed the frequency of use of this therapy and the reasons for any reduced compliance and adherence to the prescription. The aim of this study was to quantify the frequency of the participation of CHF patients in a program of domiciliary physical training and to analyze the factors that can influence adherence to the program. METHODS: Three hundred and twenty-two consecutive CHF patients (ejection fraction 28 +/- 7%) in a stable condition with optimized medical therapy performed a cardiopulmonary test, including determination of peak oxygen consumption, at baseline and after 9 +/- 3 months. All the patients had participated in sessions of health education on the relationship between illness/physical activity. The prescription of physiotherapy was decided by the physician on the basis of each patient's clinical need assessed in the diagnostic-therapeutic management. The patient referred for physiotherapy entered a therapeutic strategy that included sessions of training on anaerobic threshold, self-management of the session, and formulation of a domiciliary physical training program. During the follow-up evaluation the patients were asked to complete a questionnaire, which investigated the relationship between several factors and the patient's adherence to the physical training program, which was objectively evaluated by the change in peak oxygen consumption recorded at the end of the training, taking into account the spontaneous variations found in the control group. RESULTS: Two hundred and eighty-two of the patients (88%) satisfied the criteria for inclusion in the study. Only 61 (22%) of them were judged to have adhered to the recommended physical training. Type of employment (chi 2 = 7.08, p < 0.02), the state of retirement (chi 2 = 8.9, p < 0.01), ischemic etiology (chi 2 = 5.91, p < 0.01), compatibility with employment (chi 2 = 15.8, p < 0.0004), availability of suitable domestic conditions (chi 2 = 14.5, p < 0.0008), the structure of the training program (chi 2 = 22.33, p < 0.0001) and a learning phase in a gym (chi 2 = 71.33, p < 0.0001) were significantly correlated at univariate analysis with the performance of the physical training. Multivariate analysis identified the structure of the training program (odds ratio 9.6, 95% confidence interval 2.8-33) and a learning phase in a gym (odds ratio 49.6, 95% confidence interval 11-210.8) as independent factors (r2 = 0.48) determining adherence to the physical training program. CONCLUSIONS: Adherence to unmonitored, recommended domiciliary physical training appears to be modest even in patients who have been in-patients in a cardiac rehabilitation center. Various factors seem to influence the adherence of the patient to this therapy, but structural factors, such as the organization and learning of the program, more strongly influenced the patient's subsequent compliance.