Pulmonary hypertension due to a stiff left atrium: Speckle tracking equivalents of large V-waves.

Heart failure with preserved ejection fraction (HFpEF) is a widely heterogeneous clinical condition. Left ventricular diastolic dysfunction is the leading etiology of HFpEF, but there might be patients presenting with a predominant disease of the left atrium (LA). We report a case of HFpEF secondary to a stiff LA, in which we corroborated invasive hemodynamic assessment with LA strain analysis. Pathognomonic, tall V-waves were observed in the wedge position in the absence of mitral regurgitation and with a near-normal QRS-gated, pre-V-wave pressure, indicating that left ventricular diastolic dysfunction was not a major issue in this case. These hemodynamic findings were mirrored by very low LA strain values, compatible with a stiff and noncompliant chamber.

A brief period of intensive cardiac rehabilitation improves global longitudinal strain and diastolic function after a first uncomplicated myocardial infarction.

Objectives In patients with abnormal left ventricular ejection fraction (LVEF) after acute myocardial infarction (AMI), cardiac rehabilitation with physical training prevents cardiac remodelling. To define the role of rehabilitation in the recovery of ventricular function in less severe cases, we studied its effects on more refined indexes of left ventricular function in uncomplicated, low-risk patients. Methods and results Fifty-five patients underwent percutaneous coronary revascularization after uncomplicated first AMI. Thirty-four started cardiac rehabilitation with counselling and physical training; 21 patients did not train, followed a counselling program and were taken as controls. Echocardiography was performed at baseline, after rehabilitation or counselling program and at six months follow-up. We measured: global strain (GS%) with speckle tracking analysis, E/e' by tissue Doppler imaging (TDI), left ventricular elastance (KLV) from the deceleration time (DT), LVEF, systolic and diastolic volumes, wall motion score index (WMSI). At baseline, groups had similar GS%, KLV, LVEF, DT, E/e', systolic and diastolic volumes, WMSI. Rehabilitation increased peak VO2 by 18% (P < 0.05) and improved GS%, KLV, LVEF, E/e' and WMSI (P < 0.02) that were unchanged in controls. The improvement persisted at six months. Conclusions After a first uncomplicated AMI, abnormalities of left systolic and diastolic ventricular function may be present persisting over time despite a normal LVEF, which are fully reverted by cardiac rehabilitation.

Clinical relevance of cardiac structure and function abnormalities in patients with Cushing's syndrome before and after cure.

OBJECTIVES: Sustained hypercortisolism impacts cardiac function, and, indeed, cardiac disease is one of the major determinants of mortality in patients with Cushing's syndrome. The aim of this study was to assess the clinical relevance of cardiac structure and function alterations by echocardiography in patients with active Cushing's syndrome and after disease remission. STUDY DESIGN: Seventy-one patients (61 women, 10 men) with Cushing's syndrome and 70 age-, sex- and blood pressure-matched controls were enrolled. Echocardiography was performed in 49 patients with active disease and at several time points after remission in 44 patients (median follow-up 46.4 months), and prevalence of abnormal left ventricular mass measurements and systolic and diastolic functions indices was compared between patients with active disease, after remission and controls. Twenty-two patients were evaluated both before and after remission. RESULTS: Up to 70% of patients with active Cushing's syndrome presented abnormal left ventricular mass parameters; 42% presented concentric hypertrophy and 23% concentric remodelling. Major indices of systolic and diastolic functions, i.e. ejection fraction and E/A ratio, respectively, were normal. Upon remission of hypercortisolism, left ventricular mass parameters ameliorated considerably, although abnormal values were still more frequent than in controls. Both cortisol excess and hypertension contribute to cardiac mass alterations and increase the prevalence of target organ damage. CONCLUSIONS: Cushing's syndrome is associated with an increased risk for abnormalities of cardiac mass, which ameliorates, but does not fully disappear after remission. Systolic and diastolic functions are largely within the normal range in these patients.

Intermittent levosimendan infusions in advanced heart failure: favourable effects on left ventricular function, neurohormonal balance, and one-year survival.

The role of repeated infusions of Levosimendan (LEVO) in patients with chronic advanced heart failure is still unclear. Thirty-three patients with chronic heart failure presenting clinical deterioration were randomized 2:1 to receive monthly infusions of LEVO (n = 22) or Furosemide (Controls, n = 11). At the first drug's administration, noninvasive hemodynamic evaluation was performed; before and after each infusion, we assessed NYHA class, systolic and diastolic function, functional mitral regurgitation, and brain natriuretic peptide (BNP) levels. Noninvasive hemodynamic in the LEVO group showed vasodilation and decrease in thoracic conductance (index of pulmonary congestion), whereas in Controls, only a reduced thoracic conductance was observed. In the LEVO group, systolic and diastolic function, ventricular volumes, severity of mitral regurgitation, and BNP levels improved over time from baseline and persisted 4 weeks after the last infusion (P < 0.01). In Controls, no change developed over time in cardiac function and BNP levels. In LEVO-treated patients, 1-year mortality tended to be lower than in those treated with Furosemide. In conclusion, serial LEVO infusions in advanced heart failure improved ventricular performance and favorably modulated neurohormonal activation. Multicenter randomized studies are warranted to test the effect of LEVO on long-term outcome.

Unmasking the prevalence of amyloid cardiomyopathy in the real world: results from Phase 2 of the AC-TIVE study, an Italian nationwide survey.

AIM: To investigate the prevalence of amyloid cardiomyopathy (AC) and the diagnostic accuracy of echocardiographic red flags of AC among consecutive adult patients undergoing transthoracic echocardiogram for reason other than AC in 13 Italian institutions. METHODS AND RESULTS: This is an Italian prospective multicentre study, involving a clinical and instrumental work-up to assess AC prevalence among patients ≥55 years old with an echocardiogram suggestive of AC (i.e. at least one echocardiographic red flag of AC in hypertrophic, non-dilated left ventricles with preserved ejection fraction). The study was registered at ClinicalTrials.gov (NCT04738266). Overall, 381 patients with an echocardiogram suggestive of AC were identified among a cohort of 5315 screened subjects, and 217 patients completed the investigations. A final diagnosis of AC was made in 62 patients with an estimated prevalence of 29% (95% confidence interval 23%-35%). Transthyretin-related AC (ATTR-AC) was diagnosed in 51 and light chain-related AC (AL-AC) in 11 patients. Either apical sparing or a combination of ≥2 other echocardiographic red flags, excluding interatrial septum thickness, provided a diagnostic accuracy >70%. CONCLUSION: In a cohort of consecutive adults with echocardiographic findings suggestive of AC and preserved left ventricular ejection fraction, the prevalence of AC (either ATTR or AL) was 29%. Easily available echocardiographic red flags, when combined together, demonstrated good diagnostic accuracy.

Functional Tricuspid Regurgitation and Atrial Fibrillation: Which Comes First, the Chicken or the Egg?

Pathophysiology of "atriogenic" functional tricuspid regurgitation in patients with persistent atrial fibrillation.

Do the remodeling effects of sacubitril/valsartan treatment depend upon heart failure duration?

AIMS: The angiotensin receptor and neprilysin inhibitor (ARNI) sacubitril/valsartan (LCZ696) is recommended for the treatment of patients with heart failure in New York Heart Association (NYHA) class II-III and left ventricular ejection fraction (LVEF) 35% or less. We examined the effects of sacubitril/valsartan on cardiac remodeling and their correlation with heart failure duration in patients enrolled in our heart failure clinic from March 2017 to December 2019. METHODS: Echocardiographic and clinical/laboratory data were collected at baseline and at 6-month and 12-month follow-up visits in 69 patients (age 67 ±â€Š12 years, disease duration 8.4 ±â€Š5.8 years, 93% men). RESULTS: At both time points, mean NYHA class, NT-proBNP level, LVEF, LV end-systolic volume, and estimated systolic pulmonary pressure significantly (P < 0.05) improved versus baseline, as did the proportion of patients with diastolic dysfunction grade 3 or functional mitral regurgitation grade 3-4. In the subgroup with mean disease duration less than 8.5 years (n = 40), there was a significant improvement in all variables at both time points; in this group, a recovery of right ventricular function was also seen at the 12-month follow-up. On the contrary, patients with heart failure duration of at least 8.5 years (n = 29) showed only a slight improvement in LVEF and mitral regurgitation at 12 months. There were no significant changes in renal function and/or potassium levels in all patients. CONCLUSION: In patients with a relatively short disease duration, sacubitril/valsartan was associated with a strong favorable remodeling of the left ventricle and improvement in pulmonary circulation.

Improvement in left ventricular diastolic stiffness induced by physical training in patients with dilated cardiomyopathy.

BACKGROUND: Diastolic dysfunction in long-term heart failure is accompanied by abnormal neurohormonal control and ventricular stiffness. The diastolic phase is determined by a balance between pressure gradients and intrinsic ventricular wall properties: according to a mathematical model, the latter (ie, left ventricular [LV] elastance, K(LV)) may be calculated by the formula: K(LV) = (70/[DT-20])(2) mm Hg/mL, where DT is the transmitral Doppler deceleration time. METHODS AND RESULTS: In 54 patients with chronic systolic heart failure (39 men, 15 women; age 65 +/- 10 years; New York Heart Association [NYHA], 2.3 +/- 0.9; ejection fraction [EF], 32% +/- 5%), we analyzed the relationship between K(LV) and an index of neurohormonal derangement (levels of brain natriuretic peptide [BNP]), and investigated whether 3 months of physical training could modulate diastolic operating stiffness. Patients were randomized to physical training (n = 27) or to a control group (n = 27). Before and after training, patients underwent Doppler echocardiogram and cardiopulmonary stress test. At baseline, ventricular stiffness was related to BNP levels (P < .01). Training improved NYHA class, exercise performance, and estimated pulmonary pressure. BNP was reduced. Ventricular volumes, mean blood pressure, and EF remained unchanged. A 27% reduction of elastance was observed (K(LV), 0.111 +/- 0.044 from 0.195 +/- 0.089 mm Hg/mL; P < .01), whose magnitude was related to changes in BNP (P < .05) and to K(LV) at baseline (P < .01). No changes in K(LV) were observed in controls after 3 months (0.192 +/- 0.115 from 0.195 +/- 0.121 mm Hg/mL). CONCLUSIONS: In heart failure, left ventricular diastolic stiffness is related to neurohormonal derangement and is modified by physical training. This improvement in LV compliance could result from a combination of hemodynamic improvement and regression of the fibrotic process.

[What underlies NYHA class in elderly patients with heart failure? Role of diastolic dysfunction, functional mitral regurgitation and abnormal ventilation during exercise]. / Determinanti della classe NYHA nel paziente anziano con scompenso cardiaco: ruolo della disfunzione diastolica, dell'insufficienza mitralica funzionale e dell'alterata ventilazione durante esercizio.

BACKGROUND: Color-Doppler ecocardiography and cardiopulmonary stress test are pivotal in the evaluation of patients with heart failure. Besides determining systolic function through left ventricular ejection fraction (EF), color-Doppler ecocardiography evaluates the presence and degree of functional mitral regurgitation and the severity of diastolic dysfunction. Moreover, in addition to the aerobic capacity indicated by peak O2 consumption, other parameters of cardiopulmonary stress have proven useful for diagnostic purposes, such as the peak VE/VCO2 ratio or ventilatory efficiency. Since in elderly patients with heart failure the functional impairment often is a combination of the effects of aging with those of disease, the relationship between symptoms, i.e. the NYHA class, ventricular pump function and aerobic performance is sometimes difficult to estabilish. MATERIALS AND METHODS: In 60 elderly with systolic heart failure (75 +/- 3 years, EF 30 +/- 6%), we correlated symptoms (i.e. NYHA class) with [1] degree of functional mitral regurgitation (FMR) determined by color-Doppler echocardiography; [2] degree of left ventricular diastolic dysfunction, measured by Doppler analysis of transmitralic and pulmonary veins flow; [3] VO2 and VE/VCO2 at peak exercise at cardiopulmonary test. RESULTS: In all patients, NYHA class was only weakly related with EF and peak VO2, with wide overlap of individual values among patients with different NYHA class. Instead, we observed a tight relationship between NYHA class, FMR degree, and severity of diastolic dysfunction and VE/VCO2 ratio at peak exercise (p<0.001), with a more evident partition among patients in different NYHA classes. CONCLUSIONS: In elderly heart failure patients, the reduced effort tolerance expressed by the NYHA classification is only weakly associated with reduced aerobic capacity and pump function, but rather is related with the presence of mitral regurgitation, left ventricular diastolic dysfunction, and a poor ventilatory efficiency during exercise.

Impact of obstructive sleep apnea on cardiac organ damage in patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: Both obstructive sleep apnea (OSA) and cardiac organ damage have a crucial role in acute ischemic stroke. Our aim is to explore the relationship between OSA and cardiac organ damage in acute stroke patients. METHODS: A total of 130 consecutive patients with acute ischemic stroke were enrolled. Patients underwent full multichannel 24-h polysomnography for evaluation of OSA and echocardiography to evaluate left ventricle (LV) mass index (LV mass/BSA, LV mass/height), thickness of interventricular septum (IVS) and posterior wall (LVPW), LV ejection fraction and left atrium enlargement. Information on occurrence of arterial hypertension and its treatment before stroke was obtained from patients' history. RESULTS: 61.9% (70) of patients, mostly men (67.1%), with acute stroke had OSA (AHI > 10). Patients with acute stroke and OSA showed a significant increase (P < 0.05) of LV mass index, IVS and LVPW thickness and a significant left atrial enlargement as compared with patients without OSA. LV ejection fraction was not significantly different in stroke patients with and without OSA and was within normal limits. No relationship was found among cardiac alterations, occurrence of OSA and history of hypertension. CONCLUSION: Acute stroke patients with OSA had higher LV mass and showed greater left atrial enlargement than patients without OSA. This study confirms the high prevalence of OSA in stroke patients, suggesting also an association between OSA and cardiac target organ damage. Our finding of structural LV abnormalities in acute stroke patients with OSA suggests a potential role of OSA as contributing factor in determining both cerebrovascular and cardiac damage, even in absence of clear link with a history of blood pressure elevation.

MASked-unconTrolled hypERtension management based on office BP or on ambulatory blood pressure measurement (MASTER) Study: a randomised controlled trial protocol.

INTRODUCTION: Masked uncontrolled hypertension (MUCH) carries an increased risk of cardiovascular (CV) complications and can be identified through combined use of office (O) and ambulatory (A) blood pressure (BP) monitoring (M) in treated patients. However, it is still debated whether the information carried by ABPM should be considered for MUCH management. Aim of the MASked-unconTrolled hypERtension management based on OBP or on ambulatory blood pressure measurement (MASTER) Study is to assess the impact on outcome of MUCH management based on OBPM or ABPM. METHODS AND ANALYSIS: MASTER is a 4-year prospective, randomised, open-label, blinded-endpoint investigation. A total of 1240 treated hypertensive patients from about 40 secondary care clinical centres worldwide will be included -upon confirming presence of MUCH (repeated on treatment OBP <140/90 mm Hg, and at least one of the following: daytime ABP ≥135/85 mm Hg; night-time ABP ≥120/70 mm Hg; 24 hour ABP ≥130/80 mm Hg), and will be randomised to a management strategy based on OBPM (group 1) or on ABPM (group 2). Patients in group 1 will have OBP measured at 0, 3, 6, 12, 18, 24, 30, 36, 42 and 48 months and taken as a guide for treatment; ABPM will be performed at randomisation and at 12, 24, 36 and 48 months but will not be used to take treatment decisions. Patients randomised to group 2 will have ABPM performed at randomisation and all scheduled visits as a guide to antihypertensive treatment. The effects of MUCH management strategy based on ABPM or on OBPM on CV and renal intermediate outcomes (changing left ventricular mass and microalbuminuria, coprimary outcomes) at 1 year and on CV events at 4 years and on changes in BP-related variables will be assessed. ETHICS AND DISSEMINATION: MASTER study protocol has received approval by the ethical review board of Istituto Auxologico Italiano. The procedures set out in this protocol are in accordance with principles of Declaration of Helsinki and Good Clinical Practice guidelines. Results will be published in accordance with the CONSORT statement in a peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: NCT02804074; Pre-results.

Lung ultrasound and transthoracic impedance for noninvasive evaluation of pulmonary congestion in heart failure.

BACKGROUND: In patients with heart failure, many indexes are available for noninvasive identification of pulmonary congestion: E/E' at echocardiography; plasma levels of brain natriuretic peptide (BNP) (pg/ml); number of B-lines at lung ultrasound; and transthoracic conductance [thoracic fluid content (TFC)TT = 1/Ω] at impedance cardiography (ICG). METHODS: We obtained 75 measures from 50 patients (72 ±â€Š10 years, NYHA 2.4 ±â€Š0.7, ejection fraction 31 ±â€Š7%), 25 of them studied before and after intravenous diuretics, in whom we assessed the following: E/e' from Doppler echocardiogram; BNP plasma levels; presence and number of B-lines at lung ultrasound; and TFCTT from ICG. We determined the relationship among these indexes and their change with treatment, and compared B-lines and TFC for the diagnosis of pulmonary congestion. Finally, we considered the timing and the personnel required for performing and interpreting each test. RESULTS: A mutual relationship was observed between all the variables. After clinical improvement, changes in each variable were of similar direction and magnitude. Congestion (estimated by chest radiograph) was present in 59% of the patients: TFC value and B-line number had the best sensitivity and specificity for its detection. BNP determination and ICG assessment were performed by a nurse (15 min), and echocardiography and lung ultrasound were performed by a cardiologist (15 min). CONCLUSION: The correlation between all indexes and their consensual change after improvement of the clinical status suggests that they all detect pulmonary congestion, and that using at least two indexes improves sensitivity and specificity. The choice among the methods may be determined by the patient characteristics or by the clinical setting.

Effects of hypobaric hypoxia exposure at high altitude on left ventricular twist in healthy subjects: data from HIGHCARE study on Mount Everest.

AIMS: Previous studies investigating the effect of hypoxia on left ventricle focused on its global function, an approach that may not detect a selective dysfunction of subendocardial layers that are most sensitive to an inadequate oxygen supply. In the HIGHCARE study, aimed at exploring the effects of high altitude hypoxia on multiple biological variables and their modulation by an angiotensin receptor blocker, we addressed the effects of hypobaric hypoxia on both systolic and diastolic left ventricular geometry and function, focusing on echocardiographic assessment of left ventricle twist to indirectly examine subendocardial left ventricular systolic function. METHODS AND RESULTS: In 39 healthy subjects, physiological and echocardiographic variables, including left ventricular twist and a simplified torsion-to-shortening ratio (sTSR), were recorded at sea level, at 3400 m, and at 5400 m altitude (Mount Everest base camp). Both left ventricular twist and sTSR were greater at 5400 m than at sea level (12.6° vs. 9.6° and 0.285 vs. 0.202, P < 0.05 for both), were linearly related to the reduction in arterial oxygen partial pressure (P < 0.01 for both), and were associated with significant changes in LV dimensions and contractility. No effects of angiotensin receptor blockade were observed on these variables throughout the study. CONCLUSION: Our study, for the first time, demonstrates an increase in left ventricular twist at high altitude in healthy subjects exposed to high altitude hypoxia, suggesting the occurrence of subendocardial systolic dysfunction in such condition.

Original articles primary coronary angioplasty and subsequent cardiovascular rehabilitation are linked to a favorable sympathovagal balance after a first anterior myocardial infarction.

BACKGROUND: Modulation of the autonomic tone may contribute to the positive clinical effects of reperfusion of the ischemic zone after acute myocardial infarction (AMI). Little information exists about the effects on the sympathovagal balance of the early reopening of the vessel achieved by means of primary coronary angioplasty (PTCA). Even less is known on the autonomic effects of rehabilitation in patients undergoing PTCA. METHODS: We performed spectral analysis of the RR interval variability during 15 min of ECG in resting conditions in 51 patients (47 males, 4 females, mean age 55 +/- 6 years) 2-3 weeks after a first anterior AMI, and after 8 weeks of rehabilitation with physical training. The ratio between the low- and high-frequency (LF/HF) components of each autospectrum was used to describe the sympathovagal balance. Patients were divided into three groups: group 1 (n = 26, primary PTCA/stenting); group 2 (n = 11, recombinant tissue-type plasminogen activator); group 3 (n = 14, no reperfusion). Treatment was similar in the three groups and was maintained during the whole rehabilitation period. Results. Before rehabilitation, group 1 showed an adrenergic activation that was more blunted than that observed in groups 2 and 3. This activation was maximal in those patients with the shortest delay before the procedure. Cardiovascular rehabilitation modulated the LF/HF ratio in all groups. CONCLUSIONS: Early and effective reperfusion of the infarct-related artery is associated with a better sympathovagal tone shortly after AMI; this is followed by the known benefits of cardiovascular rehabilitation on autonomic tone.

Reverse ventricular remodeling and improved functional capacity after ventricular resynchronization in advanced heart failure.

BACKGROUND: Ventricular resynchronization is a non-pharmacological treatment for advanced heart failure refractory to drug therapy and with intraventricular conduction delay. We describe the time course of echocardiographic and functional recovery after resynchronization in 31 patients (mean age 67 +/- 8 years). METHODS: We evaluated NYHA class, echocardiogram, respiratory function, and cardiopulmonary test before pacemaker implantation (baseline), after 1-3 months (short-term evaluation), and 10-15 months afterwards (long-term evaluation, n = 21 patients). Mortality at 1 year was considered. RESULTS: Both at short and long-term, patients improved NYHA class, ventricular function, and ventricular volumes. Already at short-term, we observed an increase in oxygen consumption at peak exercise (12.6 +/- 0.6 vs 10.5 +/- 0.5 ml/kg/min), oxygen consumption at anaerobic threshold (9.8 +/- 0.6 vs 8.3 +/- 0.6 ml/kg/min) and oxygen pulse (8.3 +/- 0.5 vs 7.5 +/- 0.5 ml/beat). Ventilatory efficacy (VE/VCO2 slope) and alveolo-capillary diffusion (estimated by the measurement of lung diffusion capacity for carbon monoxide - DLCO) improved only at long-term (VE/VCO2: 40.7 +/- 1.6 vs 45.3 +/- 1.8; DLCO: 70.3 +/- 2.7 vs 59.4 +/- 5.9% of predicted, p = 0.05). The 1-year mortality was 9.7%. CONCLUSIONS: Ventricular resynchronization is linked to a fast and prolonged recovery of NYHA class, echocardiographic variables and stress tolerance. The improvement of indexes known to carry a prognostic value confirms that ventricular resynchronization can positively interfere with the evolution of the disease.

[Favourable effects of cardiovascular rehabilitation on funcional capacity and autonomic balance in elderly patients with heart failure]. / Effetti favorevoli della riabilitazione cardiovascolare su capacità funzionale ed equilibrio autonomico in pazienti anziani con insufficienza cardiaca.

In 42 patients with chronic heart failure we evaluated left ventricular function, exercise capability and autonomic control before and 3 months after a program of cardiovascular rehabilitation. The results were analyzed separately for younger (Group 1, n=18, age 51 +/- 6 years) and older patients (Group 2, n=24, age 68 +/- 4 years), with comparable clinical characteristics and therapy. Before rehabilitation, compared to younger patients, Group 2 patients showed a lower exercise capability, a comparable left ventricular ejection fraction and similar high sympathetic activity at rest, with no response to regular breathing (= stimulation of cardiopulmonary receptors, i.e. parasympathetic challenge) and active standing (= sympathetic stimulation). After rehabilitation, in both groups a 20% improvement of exercise tolerance and aerobic performance was observed, as well as a slightly increase of left ventricular ejection fraction (about 10%), and a recovery in vagal and sympathetic responsiveness. Thus, in heart failure patients age does not hinder the favorable clinical and autonomic modulation induced by cardiovascular rehabilitation.

Recovery of cardiac autonomic responsiveness with low-intensity physical training in patients with chronic heart failure.

BACKGROUND: A gradual worsening of autonomic control of cardiovascular function accompanies the progression of heart failure. Exercise training modulates autonomic balance, and may affect the prognosis of the disease. AIMS: The sympathovagal balance was studied after 3 months of low-intensity rehabilitation compared with conventional therapy in 45 patients with heart failure (52% ischemic, 48% idiopathic), of whom 30 underwent rehabilitation and 15 did not. In 11 rehabilitated patients we also studied the effects on autonomic profile of 6 additional months of home-based training. Rehabilitated and non-rehabilitated patients had similar NYHA class, ejection fraction, exercise pVO2; 50% assumed carvedilol (39+/-5 mg/day). METHODS AND RESULTS: Autoregressive power spectral density of RR intervals variability were assessed during 10 min of: (1) supine rest and free breathing; (2) supine rest and breathing at 20 acts/min (=vagal stimulus); (3) standing (=sympathetic stimulus). During each period, the ratio LF/HF of the individual autospectrum indicated the sympathovagal balance. After 3 months of rehabilitation, pVO2 increased (20%); LF/HF at rest was unchanged (8.7+/-1.2 vs. 9.2+/-1.2); it decreased with controlled breathing (-18%) and increased during standing (+79%) (P<0.05). These changes were more evident after 6 months of home-based training, when pVO2 was still high: LF/HF at rest was reduced (5.4+/-0.9 vs. 8.5+/-2.1), decreased during controlled breathing (-17%) and increased during standing (87%) (P<0.05). No changes in any variable were seen in non-rehabilitated patients. CONCLUSIONS: A low intensity rehabilitation program restores autonomic tone and reactivity to vagal and sympathetic stimuli. Some of these effects are already evident after the initial hospital-based phase.

[Does the etiology of heart failure affect tone response and autonomic reactivity to cardiovascular rehabilitation?]. / Può l'eziologia dell'insufficienza cardiaca modulare la risposta del tono e della reattività autonomica alla riabilitazione cardiovascolare?

We examined if the aetiology of heart failure could influence the favourable autonomic response to cardiovascular rehabilitation. We used the autoregressive spectral analysis of RR intervals variability, obtained from 10 minutes of ECG recording: within each autospectrum, we calculated the power of the low (LH) and high frequency (HF) oscillations: their ratio LF/HF is a useful, well accepted index of the sympathovagal balance. In 43 patients with heart failure we evaluated the autonomic tone at rest, during regular breathing (= stimulation of cardiopulmonary receptors, i.e. a parasympathetic challenge) and during active standing (= sympathetic stimulation). The shift in such autonomic response to 3 months of cardiovascular rehabilitation was analyzed separately for patients with ischemic (n = 19) and non-ischemic (n = 24) cardiomyopathy. Before rehabilitation, patients with ischemic cardiomyopathy had a higher sympathetic activity at rest, and a preserved response to parasympathetic stimulation. After rehabilitation, both groups of patients showed an improvement in exercise tolerance and performance, no deterioration in ventricular pump function, and a change in the autonomic profile. Thus, the aetiology of heart failure, despite a different baseline sympathovagal balance, does not influence the favourable clinical and autonomic modulation induced by rehabilitation. Independently from the underlying disease, all clinically stable patients with heart failure can benefit from rehabilitation.