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The increasing evidence on the favourable cost/effectiveness impact of the comprehensive cardiac rehabilitation program for the treatment of a wide spectrum of cardiovascular conditions have imposed to healthcare services a major attention on a critical analysis of the results in different clinical indications and delivery organisations. The Regional Health Agency of Liguria, in the occasion of drawing up regional guidelines directed to define the clinical indications and the effectiveness of the cardiac rehabilitation delivery model (in-patients, out-patients and home-based) and its requisites, indications and procedures, has updated the reference guidelines (PLNG and SIGN) with the evidence provided by the more recent literature, focusing its attention on the clinical and, in particular, organizational effectiveness. The document, on the base of these evidences, provides some effective proposals and some organizational advices.

Limited functional capacity has an important negative predictive value both in normal subjects and in patients with heart disease. In heart failure patients the improvement in physical capacity produces an increase in survival and a reduction in morbidity and hospital admission. The main cause of physical capacity reduction in heart failure elderly patients is represented by structural modifications of peripheral muscles and reduced vasodilating capacity of perimuscular vessels. Physical training induces a regression of these alterations, restore endothelial function and has favorable effects on left ventricular diastolic function and on ventilatory alterations. Data on the effects of physical training in older patients with heart failure are numerically limited, but it is possible to affirm that a minimum of 20 min of physical training for 3 days a week at 40% of maximal effort capacity are able to produce beneficial effects. Physical training in patients with heart failure, also in advanced age, is safe, has to be encouraged, and induces a significant improvement in quality of life and survival.

Exercise capacity is reduced in many patients with cardiovascular disease. In post-acute myocardial infarction, ischemic heart disease and heart failure patients, exercise capacity has a strong independent prognostic impact. Even in subjects without history of heart disease, the lower the cardiorespiratory fitness the higher is the risk for cardiovascular events and mortality. With appropriate physical activity, exercise capacity is improved in most individuals. Improvement of functional capacity is associated with improvement of survival.

In this review the meaning of exercise electrocardiographic changes and interpretative pitfalls in particular clinical conditions are critically reassessed. Existing studies have been carried out on different populations and with different gold standards, nevertheless exercise testing if correctly analyzed and interpreted, can provide invaluable information for diagnosis of coronary artery disease. Given its feasibility, diffusion and low risk, it remains indeed the first choice test in the diagnostic algorithm of ischemic heart disease. The use of more sophisticated and expensive tests have to be limited to selected groups of patients in whom exercise testing, correctly interpreted, remains really doubtful or prematurely interrupted.

The search for the ideal antihypertensive drug is ongoing. Carvedilol is a new beta-adrenoceptor antagonist which also causes peripheral vasodilation primarily via alpha 1-adrenergic blockade. Twenty patients with mild to moderate essential hypertension and previous intolerance and side effects to other antihypertensive drugs were studied. After initial baseline assessment, patients received 25 mg carvedilol orally q.d. The treatment lasted 60 days. In our study carvedilol was well tolerated and no important side effect was recorded. Blood pressure decreased significantly to normal values, without orthostatic blood pressure decreases. Heart rate decreased significantly too, but no significant bradycardia was induced. No negative effects on serum lipids and no clinical evidence of increase in peripheral resistance were observed. Ventricular arrhythmia on Holter monitoring were significantly reduced after treatment with carvedilol.

Spectral analysis of r-r variability has been recently proposed as a clinical tool to assess the autonomic nervous system function. In this article we present the results obtained using an equipment and an analysis software (based on Maximum Entropy Method) developed in our laboratory. Analyzing the tachograms derived from prolonged ECG registrations of 12 young healthy subjects, 24 to 36 years old (mean 31 +/- 4), we observed the two classic components of the signal: a low frequency component (0.7 +/- 0.2 Hz) and a high frequency component (0.21 +/- 16.6 Hz). As expected, standing, a simple manoeuvre augmenting sympathetic activity, caused a stronger predominance of the low frequency component. We conclude that our method is reliable to evaluate, by means of spectral analysis, rhythmical oscillations of r-r variability.

Blood pressure ambulatory monitoring has provided numerous and interesting informations on the clinical as well as investigational setting of arterial hypertension. The vast majority of data have been obtained registering blood pressure during the normal daily activities of the patients and surprisingly few studies have been undertaken to evaluate blood pressure behaviour in inpatients. We observed the 24 hours pattern of blood pressure in hypertensive and normotensive inpatients, using an automated sphygmomanometer (Omega 1400), whose performance was previously evaluated by us. The results demonstrate that blood pressure monitoring in inpatients could be a useful tool in managing hypertensive patients.

Subclinical elevation of urinary albumin excretion is a good predictor of later clinical proteinuria. A simple, sensitive and rapid immunoturbidimetric method was developed to quantify urinary albumin excretion (URIN-PAK ImmunoMICRO LAB, Miles Italia Spa). In the presence of polyethylene glycol 6000, immunocomplex between human albumin and its specific antibody are rapidly formed (5-50 min, at room temperature). Absorbance reading are mode U 340 nm (Automatic Analyzer RA 1000, Technicon). The test is specific for albumin failing to cross react with other plasma proteins present in urine, as well as with glibenclamide, chlorpropamide, phenformin, hemoglobin, glucose, urea and thymol. The present method correlates with SCLAVO H-ALBUMIN RIA Kit (r = 0.9917). The test is suitable for clinical use.

24 hour pressure monitoring is a newly developing technique potentially yielding important informations in hypertensive patients. Numerous automated devices are available whose performance characteristics are poorly documented. To evaluate an automated sphygmomanometer commonly used in our Division (Omega 1400, Invivo Research Laboratories), we performed a series of measurements, simultaneously recording blood pressure in the opposite arm with a common sphygmomanometer. Each measure was then repeated reversing the position of the two devices (manual and automated), thus abolishing possible differences between the two arms. We observed a mean underestimation of 1.90 mmHg of systolic pressure and of 4.82 mmHg of diastolic blood pressure by the automated device. We conclude that the device by us evaluated is not advisable in the basal blood pressure evaluation, but useful in monitoring inpatients.

The normal range and the reproducibility of the cardioinhibitory carotid sinus reflex were studied in 288 apparently healthy subjects of different ages (aged from 17 to 84 yrs., 156 males, 132 females). In each subject we chose the longest RR interval as an activation index of the reflex obtained by carotid sinus massage; its mean value increased slightly with advancing age. In the were 1, 5, 2, 5, 3, 3 sec. respectively, with a 99% confidence limit. No sex difference was found. We studied also a group of 105 patients (aged from 39 to 82 yrs., 67 males, 38 females) with various types of cardiovascular disorders, without a previous history of spontaneous syncope. Abnormal maximum RR values were found in 18 of them (17%). This percentage was significantly higher than in normals (2%). In 11 patients (10%) the carotid sinus stimulation evoked a syncopal attack. It seems therefore that a statistically abnormal carotid sinus hypersensitivity can occur in a substantial number of cardiovascular patients without necessarily leading to spontaneous syncopal attacks. Finally the reproducibility of the cardioinhibitory reflex was tested in 42 patients with maximum RR interval values ranging from normal to extremely abnormal. In each subject a significant correlation (r = 0.79) was found between the maximum RR interval values tested in two occasions at intervals ranging from 1 hour to 3 months; besides a concordance in normal or abnormal result was present in 93% of the cases.