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Aims The 6-min walk test has been incorporated into studies on the efficacy of new therapies and into prognostic stratification for chronic heart failure patients. Firm conclusions on the usefulness of the test in clinical practice are still lacking. The aim of this study was to investigate (1) the correlation between walk test performance and standard indices of cardiac function and exercise capacity, and (2) the prognostic value of the walk test with respect to peak VdotO2and NYHA class.Methods and Results Three hundred and fifteen chronic heart failure patients (age: 53±9 years, NYHA class: II (182), III (133)) underwent a functional evaluation and a 6-min walk test. Of these, 270 were followed-up for a minimum of 6 months (mean 387±177 days). Walked distance was 396±92m. There was no significant correlation between distance walked and central haemodynamic data. Functional capacity, as measured by ergometry, correlated moderately with distance walked (duration: r=0·48, peak VdotO2: r=0·59, anaerobic threshold: r=0·54; all P<0·001). During follow-up, 46 patients died from cardiovascular causes and 12 were urgently transplanted. Either of these events were considered end points of the study. Survival analysis was performed from a continuous walk test and peak VdotO2measurements or after categorization of (a) quartile segmentation, (b) cut-off points from the literature and (c) thresholds from receiver operating characteristic curves. At univariate survival analysis (Cox regression), the association of the walk test with survival was of significance (P=0·03, continuous variable), or borderline significance (0·05≤P≤0·1, after categorization). Peak VdotO2was always significant, indepedent of the scale used (0·005≤P≤0·03). The strongest association was found for NYHA class (P<0·001), which showed the highest sensitivity and specificity for the prediction of the event (0·64 and 0·65, respectively). When walk test performance, continuous or categorized, was entered into a multivariate model with NYHA class or peak VdotO2, it lost any significant association with survival (P>0·76 in all models with NYHA class andP >0·27 in all models with peak VdotO2).Conclusion In moderate-to-severe chronic heart failure patients, the 6-min walk test is not related to cardiac function and only moderately related to exercise capacity. Walking performance does not provide prognostic information which can complement or substitute for that provided by peak VdotO2or NYHA class. Hence the test is of limited usefulness as a decisional indicator in clinical practice. [ABSTRACT FROM PUBLISHER]

Aim To analyse the relationships between the psychological profile, the satisfaction profile and cardiological variables in patients with chronic heart failure.Material and Methods One hundred and fifty-two male patients with chronic heart failure in a stable clinical condition underwent cardiological evaluation and psychological assessment by means of two instruments: the Cognitive Behavioural Assessment 2.0 Battery and the Satisfaction Profile.Results Patients scored higher than healthy subjects in terms of psychophysiological disorders and depression. Patients in NYHA class III reported higher anxiety and depression scores and had more frequent problems in daily life than patients in NYHA classes I and II. Class III patients also reported lower satisfaction levels in many aspects of psychological and physical functioning. Pulmonary resistances >2·5 Wood units, pulmonary capillary wedge pressure >0·18mmHg and a diagnosis of ischaemic cardiomyopathy were associated with low satisfaction levels in the Satisfaction Profile ‘physical functioning’ factor. To be listed for heart transplantation and a history of more than three hospitalizations were related to low satisfaction levels in many items of the Satisfaction Profile. Finally, stepwise multiple regression showed that NYHA class, depression score and pulmonary capillary resistance accounted for 32% of the variance in the Satisfaction Profile physical functioning factor score.Conclusion On the basis of chronic heart failure diagnosis only, a generic pattern of psychological distress can be predicted, common to many severe chronic diseases. Shifting from objective mental health measures towards the domain of subjective satisfaction, the only link which emerges is between objective cardiological data and satisfaction with physical functioning. Satisfaction in terms of other life aspects does not seem to be related to cardiological variables.These results support the importance of subjectivity in health related quality of life, as well as objective measures. [ABSTRACT FROM PUBLISHER]

Aims To evaluate the relationship of skeletal and respiratory muscular dysfunction with the degree of clinical severity, cardiac impairment and exercise intolerance in patients with chronic heart failure.Methods and Results Ninety-one patients (age 52·7±8 years) on standard therapy and in a stable clinical condition with normal nutritional status underwent evaluation of (1) clinical severity and metabolic status (NYHA class, weight, albuminaemia, natraemia, cortisol, insulin, neurohormones), (2) cardiac function (Echo, right heart catheterization), (3) exercise tolerance (peak VO2), (4) dynamic isokinetic forces of the quadriceps and hamstring (Cybex method), and respiratory muscle strength (maximal inspiratory and expiratory pressures). Fifty patients had a peak VO2<14ml.kg−1.min−1(10·6±2) and 41 had values ≥14 (18·3±4). In the former group, leg and respiratory strength were significantly lower (extensors: 80±24 vs 100·9±22Nm; flexors: 48·5±24 vs 75·3±22, bothP <0·001; maximal expiratory pressure: 85·5±30 vs 104·8±31,P <0·01). Muscular strength was not related to indices of clinical severity, metabolic status, neurohormones or to the degree of systolic/diastolic cardiac function, but it was related to weight and age. Multivariate analysis of the peak VO2with clinical, haemodynamic and peripheral indicators showed weight (beta=0·32,P =0·007), muscular strength (beta=0·32,P =0·01) and NYHA class (beta=0·31,P =0·001) as the only independent predictors. The joint adjusted R2value was 0·48 (P<0·001).Conclusion Muscular dysfunction is part of the syndrome of heart failure. Together with symptom perception, it predicts nearly half of the variation in exercise tolerance. [ABSTRACT FROM PUBLISHER]

To assess the clinical significance of monitoring during physical training in post-myocardial infarction (MI) patients with asymptomatic exercise-induced ischaemia, we studied 232 patients who were survivors of first recent acute MI and consecutively admitted to the same CCU, who underwent an exercise test (ET) and coronary angiography within two months of the acute event. We selected the 97 patients with multivessel disease. Among them, 60 showed a negative ET and no angina; 37 showed a positive ET with significant ST segment depression, 32 of them had no angina. The 37 patients with positive ET repeated the stress test within a week. In eight of them, the two ETs differed because ischaemia was induced once with and once without precipitation of angina, while the workload (WL) and double product (DP) at the ischaemic threshold of 0.1 mV ST segment depression were not different. During a four-week training period, seven of the asymptomatic patients complained of effort angina and three of angina at rest.To assess training effects, we selected 60 non-consecutive patients with asymptomatic (38) and symptomatic (22) exercise-induced ischaemia. All the symptomatic and 25 asymptomatic patients followed a four-week physical training programme based on the ischaemic threshold. The remaining 13 asymptomatic patients did not undergo physical training. The pre-training period ergometric patterns were comparable between painful and pain-free patients. Training resulted in a similar increase in the WL at the ischaemic threshold (+45% in asymptomatic and +47% in symptomatic patients, both P < 0.05), without any difference in the DP threshold. Comparing trained and untrained patients with asymptomatic ischaemia, there was a statistical difference in the improvement of the WL threshold (+45% in the trained and +6% in the untrained patients).In conclusion: (i) in post-MI patients with multivessel disease and ST segment depression during exercise the prevalence of asymptomatic exercise-induced ischaemia was 33%; (ii) both symptomatic and asymptomatic episodes have been found in some patients without any relationship with the amount of ischaemia; and (iii) physical training was similarly effective in modifying the ischaemic threshold in painful and painless patients. [ABSTRACT FROM PUBLISHER]

The resting and exertional haemodynamic effects of acute and chronic discontinuous (one tablet every 6 h) treatment with 5 mg of buccal nitroglycerin (BN) have been assessed in nine postinfarction heart failure patients. At rest, pulmonary artery ( PAP), pulmonary wedge ( PW P ), and right atrial pressures (RAP) were reduced by 42%, 55% and 77%, respectively, after the first dose and by 26%, 32% and 45%, respectively, after the chronic (three weeks) treatment with BN. During exercise, at the same workload, PAP, PWP and RA P were significantly reduced by 44%, 54% and62%, respectively, after acute treatment and by 28%, 34% and44%, respectively, after chronic treatment. The maximal workload (Kgm) increased by 179% and 166% and the exercise time increasedby 78% and 71% after acute and chronic therapy, respectively. At the maximal workload, after acute BN, overall haemodynamics were better than in the basal state. PA P, P WP and RA P were still reduced by 19%, 31% and 31%, respectively, after acute treatment, while after chronic phase the results did not differ from control. The severity of cardiac failure, according to the Weber classification, was reduced by acute and chronic therapy. We can conclude that the buccal nitroglycerin showed clear efficacy in improving overall haemodynamic parameters both at rest and during exercise in post-myocardial infarction patients with heart failure. The discontinuous treatment maintained the effect of nitroglycerin without clear evidence of tolerance during chronic therapy. [ABSTRACT FROM PUBLISHER]

Recently, more attention has been focused on the detection and treatment of silent myocardial ischaemia. Electrocardiographic signs of exercise-induced asymptomatic myocardial ischaemia are very common findings among survivors of acute myocardial infarction. From data of our population we found that silent exercise-induced ischaemia is present in 15–20% of all patients, and that about half of the patients with exercise-induced ST-segment depression were free of symptoms. Ergometric data at the ischaemic threshold are similar between asymptomatic and symptomatic patients while the presence of symptoms is more frequent in patients who were also symptomatic before the myocardial infarction. During the training period, the majority of the ‘silent’ patients remained asymptomatic, 23% developed effort angina, and 9% developed angina at rest. Training monitoring may be helpful in identifying the variability of symptoms. Physical training, in particular an intermittent programme, increased the work-load at which the ECG ischaemic signs appeared. Among the possible mechanisms responsible for exercise-induced silent ischaemia, a different pain tolerance and control of analgesia may be ascribed to explain the absence of pain, perhaps also determined by different endogenous beta-endorphin levels. [ABSTRACT FROM PUBLISHER]

The anaerobic threshold (AT) has been proposed as an index to assess the functional status of patients with chronic heart failure. The focus of this report was to evaluate in post-myocardial infarction patients the utility of the AT for (a) assessing the severity of exercise-induced left ventricular impairment, (b) determining the responses obtained from different treatments and (c) prescribing exercise training.We found that the AT level was lower in patients with abnormal haemodynamic patterns during exercise. The AT was correlated to different degrees of exercise-induced left ventricular impairment.The nitrate and calcium-antagonist effects have been evaluated in patients with abnormal exercise haemodynamics. The resting and exertional results were in agreement with the vasodilator effects. Moreover, the time from onset of exercise to the appearance of the AT was significantly increased by the treatments. Thus, AT during pharmacological treatments may be a non-invasive useful parameter for assessing their haemodynamic effects.Finally, a 4-week intermittent training programme based on AT level was evaluated in patients with abnormal resting and exertional haemodynamics. The results showed an improvement of the exercise cardiovascular tolerance without negative effects on left ventricular function.Therefore, the AT seems to be useful when prescribing a rational and individualized training programme. [ABSTRACT FROM PUBLISHER]

A single blind study between placebo and diltiazem (25 mg i.v. single dose) was carried out on 20 male patients with previous myocardial infarction and without exertional ischaemia. Patients, 50 ±6.1 (mean±SD) years of age, underwent a right heart catheterization with Seldinger's percutaneous approach and brachial or radial artery percutaneous catheterization. Haemodynamic variables were recorded in the supine position after catheterization in baseline conditions at rest, after a warming-up period of 6 min, before and after a first and second exercise test with stepwise increments of 25 W per 3 min. Before the second exercise test, either placebo or diltiazem (25 mg) was injected intravenously in 3 min. In comparison with placebo, diltiazern significantly reduced resting blood pressure (P<0.001) and systemic vascular resistance (P<0001) and increased cardiac index (P<0.01); during exercise it also reduced the mean pulmonary arterial pressure (P<005), pulmonary wedge pressure (P<0.05), total pulmonary resistance (P<0.02), and increased the stroke volume (P<005). The present study demonstrated that intravenous diltiazem did not induce a significant rise in cardiac index but reduced the afterload and slightly reduced the preload. Diltiazem also reduced myocardial oxygen consumption and decreased blood pressure, mean right atrial pressure and slightly decreased the heart rate. [ABSTRACT FROM PUBLISHER]

In order to determine individual variability of ischaemic threshold on different days, 18 patients with exertional ischaemia at low workload were studied. All patients performed two exercise tests during different days in the morning and three on the same day at 9 am, 2 pm and 5 pm. The test performed in the morning on different days resulted in a significant difference in the mean values of rate pressure product at the ischaemic threshold as a consequence of individual variability observed in 10 patients. In 8 of these patients the differences were greater than 4000 mmHg beats min. Two patients showed respectively, 1 and 5 negative exercise tests despite the greater values of rate pressure product reached. Only 3 patients showed circadian variation of the ischaemic threshold; in these 3 patients variations of rate pressure product at the ischaemic threshold were also observed between different days. These data indicate that in patients with exertional ischaemia at low workload the rate pressure product at the ischaemic threshold shows considerable variability between tests performed on different days. [ABSTRACT FROM PUBLISHER]

This study was designed to assess, by two-dimensional echocardiography, the effects of anticoagulant therapy on left ventricular thrombosis detected after acute myocardial infarction. Thirty-eight patients with left ventricular thrombi detected by two-dimensional echocardiology within 5 weeks (mean 4) of the onset of infarction were randomly assigned to the following groups: group A consisted of 19 patients who received oral anticoagulants (acenocoumarin 1.6 mg daily regulated to keep prothrombin time within the range of 25 to 35%) and group B which consisted of 19 non-treated control patients. Seventeen patients from both groups were restudied 15 days, 3 months and one year later to evaluate the changes in size of thrombi. Echocardiographic examinations were read blindly; a significant decrease in ventricular thrombus size was taken as a ≥ 5 mm reduction of thickness in the apical views. In Group A, 9 patients showed a complete resolution of thrombus at the 15 day study; at one year, thrombus had resolved in 15 and persisted unchanged in size in 2 patients. The mean dimension of thrombi in patients of group A was 18±6.6 mm at the screening examination and decreased to 6.6mm, 3.8mm and 2.2mm, respectively, at 15 days, 3 months and one year follow-up studies. Among 17 patients of group B at the 15 day study, two had resolution of thrombus and 15 were unchanged; at the one year examination thrombus was resolved in 4, decreased in size in 4 and persisted unchanged in 9 patients. Analysis of variance of the dimensional changes of thrombi in the two groups of patients confirmed a significant efficacy of anticoagulant therapy (P<0.001). On the basis of our results we conclude that full-dose anticoagulant therapy, started early (within 5 weeks) after acute myocardial infarction, is effective in the resolution of left ventricular thrombosis. [ABSTRACT FROM PUBLISHER]

In patients with heart failure the risk of systemic thromboembolism and the benefit of anticoagulation are uncertain. To assess the incidence of systemic thromboembolism and the factors associated with an increased risk, 406 consecutive patients with chronic heart failure were prospectively investigated. Their left ventricular ejection fraction was 23±8%, pulmonary wedge pressure 19±10 mmHg and cardiac index 2.3±1.41. min−1 . m−2 of body surface area. Two hundred patients were in NYHA functional class III-IV. Two hundred and thirty-two patients were receiving oral anticoagulants. Over a follow-up period of 16±11 months, thromboembolism occurred in 11 patients (2.7%), seven of whom were on anticoagulants. Among clinical, echocardiographic and haemodynamic variables, atrial fibrillation, more severe haemodynamic impairment and low exercise capacity were associated with increased thromboembolic risk. No echocardiographic findings, including the presence of intracavitary thrombi, either at baseline or during follow-up, were related to subsequent thromboembolic events. The rate of embolism did not differ in patients receiving anticoagulants (4%) compared with those who did not receive anticoagulants (1%). No major bleeding occurred during follow-up. Thus, in patients with chronic heart failure and sinus rhythm the incidence of systemic thromboembolism is low regardless of anti coagulant treatment. Atrial fibrillation, particularly when associated with low cardiac index, identifies a subgroup of patients at high risk of events. In this subgroup, a moderate-intensity anticoagulant regimen provides unsatisfactory protection against thromboembolism. [ABSTRACT FROM PUBLISHER]

Fifty male patients older than 65 years of age (mean 66·3) underwent a symptom-limited exercise test on an average of 34 days after acute myocardial infarction. After 4 weeks of supervised rehabilitation training and after one-year follow-up, the patients underwent controlled exercise tests. The ergometric parameters were compared with respective values in 10 healthy males (mean age 66·4, range 65–75). The rehabilitation training induced a substantial improvement in physical capacity (total work from 3149±1326 to 4791 ± 1403 kg; P<0·001) with a better cardiovascular response: increased maximum oxygen pulse (from 8·97±2 to 10·7±2; P<0·001), decreased heart rate (from 120·5±16·1 to 111·3±14·7beats min−1; P < 0·05) and a decreased double product at a 75 W work load (from 22 866 ± 4005 to 20 472 ± 3982 beats min−1 mmHg; P<0·05). The recovery of physical capacity and cardiovascular tolerance in the physical exercise was nearly complete as compared with healthy subjects of the same age. During the training period one patient died from heart failure. In all the other patients the same improvement was still maintained one-year later.In conclusion, old age does not seem to be per se a contraindication to cardiac rehabilitation. Physiological beneficial effects from cardiac rehabilitation can also be received by patients older than 65 years of age. [ABSTRACT FROM PUBLISHER]

Aims: The addition of trimetazidine to standard treatment has been shown to improve left ventricular (LV) function in patients with heart failure. The aim of this study is to non-invasively assess, by means of in vivo 31P-magnetic resonance spectroscopy (31P-MRS), the effects of trimetazidine on LV cardiac phosphocreatine and adenosine triphosphate (PCr/ATP) ratio in patients with heart failure., Methods and Results: Twelve heart failure patients were randomized in a double-blind, cross-over study to placebo or trimetazidine (20 mg t.i.d.) for two periods of 90 days. At the end of each period, all patients underwent exercise testing, 2D echocardiography, and MRS. New York Heart Association (NYHA) class, ejection fraction (EF), maximal rate-pressure product, and metabolic equivalent system (METS) were evaluated. Relative concentrations of PCr and ATP were determined by cardiac 31P-MRS. On trimetazidine, NYHA class decreased from 3.04+/-0.26 to 2.45+/-0.52 (P = 0.005), whereas EF (34+/-10 vs. 39+/-10%, P = 0.03) and METS (from 7.44+/-1.84 to 8.78+/-2.72, P = 0.03) increased. The mean cardiac PCr/ATP ratio was 1.35+/-0.33 with placebo, but was increased by 33% to 1.80+/-0.50 (P = 0.03) with trimetazidine., Conclusion: Trimetazidine improves functional class and LV function in patients with heart failure. These effects are associated to the observed trimetazidine-induced increase in the PCr/ATP ratio, indicating preservation of the myocardial high-energy phosphate levels.

Aim: Metabolic exercise abnormalities have been reported in chronic heart failure patients. This study sought to evaluate whether these abnormalities affected daily activity., Methods and Results: In 16 patients with moderate-to-severe chronic heart failure and in eight controls we measured femoral flow (thermodilution) and metabolism (glucose, lactate, free fatty acids, blood gas values) at rest and during a constant load of 20 W, which may mimic a daily activity. At rest, chronic heart failure patients had a leg flow similar to controls, but showed a higher leg oxygen consumption (4.6 +/- 0.6 vs 2.6 +/- 0.4 ml.min-1; P < 0.05), a higher arteriovenous oxygen difference (7.2 +/- 0.5 vs 5.4 +/- 0.7 ml.dl-1; P < 0.05), and a lower femoral vein pH (7.37 +/- 5.03 vs 7.42 +/- 0.01; P = 0.01). At 20 W, chronic heart failure patients had a leg flow similar to controls, but showed increased lactate release (from resting 11.7 +/- 33 to 142 +/- 125 micrograms.min-1 P < 0.0001 vs controls, from resting 5.7 +/- 15.4 to 50 +/- 149 micrograms.min-1 ns), higher arterial concentration of free fatty acids (781 +/- 69 vs 481 +/- 85 mumol.l-1; P < 0.01), lower femoral vein HCO3 (24.1 +/- 2.6 vs 26.3 +/- 1.7 mmol.l-1; P < 0.05) and base excess (-2.3 +/- 2.3 vs -0.24 +/- 1.7 mmol.l-1; P = 0.01)., Conclusion: In chronic heart failure patients, the important cellular metabolic alterations already present at rest partially affect daily activities, owing to a further decrease in the efficiency of muscle metabolic processes, and may preclude tolerance of heavier activities. Such alterations appear, at least in part, independent of peripheral haemodynamic responses to exercise.

The resting and exertional haemodynamic effects of acute and chronic discontinuous (one tablet every 6 h) treatment with 5 mg of buccal nitroglycerin (BN) have been assessed in nine postinfarction heart failure patients. At rest, pulmonary artery (PAP), pulmonary wedge (PWP), and right atrial pressures (RAP) were reduced by 42%, 55% and 77%, respectively, after the first dose and by 26%, 32% and 45%, respectively, after the chronic (three weeks) treatment with BN. During exercise, at the same workload, PAP, PWP and RAP were significantly reduced by 44%, 54% and 62%, respectively, after acute treatment and by 28%, 34% and 44%, respectively, after chronic treatment. The maximal workload (Kgm) increased by 179% and 166% and the exercise time increased by 78% and 71% after acute and chronic therapy, respectively. At the maximal workload, after acute BN, overall haemodynamics were better than in the basal state. PAP, PWP and RAP were still reduced by 19%, 31% and 31%, respectively, after acute treatment, while after chronic phase the results did not differ from control. The severity of cardiac failure, according to the Weber classification, was reduced by acute and chronic therapy. We can conclude that the buccal nitroglycerin showed clear efficacy in improving overall haemodynamic parameters both at rest and during exercise in post-myocardial infarction patients with heart failure. The discontinuous treatment maintained the effect of nitroglycerin without clear evidence of tolerance during chronic therapy.