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A 50-years-old man with severe heart failure was diagnosed to have congestive cardiomyopathy and low atrial tachycardia at a fixed rate of 103 bpm. Conventional therapy for heart failure exerted a beneficial effect but complete clinical improvement was achieved only by reducing the rate of low atrial tachycardia with amiodarone. This suggests that in this situation tachycardia itself played a main role in the genesis of hemodynamic derangement.

Aging-induced cardiac modifications are almost never different--at least qualitatively--from those linked to chronic pathologies that are usually found in advanced age. Due to many factors, as myocyte hypertrophy, increase in the amount of collagen and subepicardial fat accumulation, the aging heart increases its own weight. All cardiac structures undergo regressive modifications: valvular apparatus show fibrosis, collagen fragmentation, lipid accumulation and calcifications, the coronary arteries are characterized by tortuosity, minimal atherosclerotic lesions, calcium precipitates and--at least in animals--by an imbalance between the capillary bed extension and the myocyte hypertrophy. The most peculiar changes of interstitium, aside from fibrosis, are represented by lipofuscins and amyloid deposits. From a functional point of view, the aging heart does not show any substantial difference from the adult one in the basal state. Cardiac output seems to be maintained during exercise in the elderly. Nevertheless, such a result is achieved by an end-diastolic volume increase, instead of positive chronotropic and inotropic response and to the peripheral resistance decrease of the younger. This could be partly due to a damped cardiovascular response to sympathetic beta-receptor stimulation. The diastolic phase undergoes a progressive dysfunction, as its duration increases, the early filling falls and the atrial contribution plays a major role. The reduction of many mitochondrial enzymatic processes--such as fatty acid oxidation and oxidative phosphorylation--has been documented in animals, as well as transmembrane ionic fluxes alteration. The maximal oxygen consumption is progressively reduced, although this does not seem to be due to a cardiac performance impairment.(ABSTRACT TRUNCATED AT 250 WORDS)

The therapeutic management of elderly patients should be extremely careful, particularly in those over 75 years of age. As a matter of fact, in such patients a steep increase of the risk of comorbidity and of dependence has been evidenced. This implies a more complex therapeutic management, that must be oriented to the amelioration of quality of life more than to the resolution of the single pathologies. However, all the intervention trials so far conducted excluded such patients. Therefore, they cannot be considered representative of the geriatric epidemiological reality. As a result, there is virtually no useful information on the efficacy and safety of cardiovascular drugs in patients over 75 years of age. However, the following items should be pointed out: only drugs whose efficacy has been proved should be used, and only after a thorough diagnosis; a multidimensional evaluation should be performed, also addressing psychological, social, environmental and economical factors that could affect the clinical course; the risks and benefits of any therapy should be considered, particularly in the presence of comorbidity, as the number of assumed drugs directly correlates with the risk of developing adverse reactions; drugs should be dosed according to renal function and body weight, possibly starting with half the dosage of younger patients; after starting the therapy, patients should be kept under strict clinical control, and every new symptom should be considered an adverse reaction, unless it will not disappear after withdrawal of the drug; serum drug concentration should be monitored whenever possible, given its larger variability in advanced age.