[Cardiology of yesterday, today and tomorrow].

The subject of this lecture has been chosen in relation to the contribution that Professor H Alessandri made in the first half of this century, as an outstanding clinician in the professional, humanistic and ethical development of generations of physicians in this country. This lecture is divided in three sections: the first reviews the practice of cardiology in the 50's, a period of initiation of the present advances in the specialty, still dominated at that time by a semiologic and clinical approach. The second part presents examples of the significant contributions made by newer technologies in the fields of echocardiography, nuclear medicine, electrophysiology and therapeutic procedures.

[Prospective study on post-acute myocardial infarction patients].

Long-term prognosis in acute myocardial infarction (AMI) can be related to a number of risk factors, including the electrocardiographic stress test (ECG Test). This study analyzes its contribution to the prognosis and management of such patients. 60 individuals discharged from a coronary care unit, without or with persisting complications underwent an ECG test 4-6 weeks following AMI, and were followed for a period of 12-39 months.

[Ventricular extrasystole and coronary disease: to treat or not to treat?].

The prognostic significance of ventricular premature beats (VPB) and their proper management are still a subject of controversy, particularly since during the last few years a number of publications have raised doubts as to the effectiveness and safety of antiarrhythmic drugs. An appropriate assessment of the VPB must consider: 1) electrocardiographic characteristics. 2) Associated symptoms.

[Controversies on digitalis].

The introduction of newer drugs with effective cardiovascular action to clinical practice has reduced dependence on digitalis compounds. This tendency has been further justified by statements to the effect that consistently satisfactory results can be obtained with alternative drugs; that the inotropic action of digitalis is not evident in patients with normal sinus rhythm; that digitalis increases myocardial oxygen consumption, and finally that the high incidence of intoxication should limit its use. The present article reviews the use of alternative agents; the inotropic effects of digitalis in the presence of sinus rhythm; the implications of the use of drugs augmenting contractility upon total myocardial performance and oxygen consumption, and the factors pertinent in favoring digitalis toxicity.

[Silent myocardial ischemia].

During the last few years, the concept of "silent myocardial ischemia" has received special attention, particularly regarding its prognostic implications. Unfortunately a great variety of patients in different clinical settings have been included under the same definition. Thus, totally asymptomatic individuals are considered together with patients who have clinically evident stable or unstable angina pectoris, or patients in the post myocardial infarction phase.

[Cardiogenic shock].

In spite of advances in our understanding of the pathophysiology of cardiogenic shock, and the introduction of potent vasoactive pharmacological agents in its management, prognosis continued to be dismal with hospital mortalities over 85%. It has been only through additional and aggressive interventions--including intraaortic balloon counterpulsation (IABC), percutaneous transluminal coronary angioplasty (PTCA) and surgical revascularization--that improved survival can be achieved. Today's management of cardiogenic shock requires an early and integrated approach including physiological monitoring, vasoactive drugs, IABC, coronary angiography and PTCA, with the expectation of improving prognosis.

Effects of dobutamine on atrioventricular conduction.

Dobutamine, a new beta-stimulating catecholamine, has been investigated in terms of its effect upon atrioventricular conduction. Bundle of His recordings were obtained on six patients in basal conditions and with right atrial pacing at rates of 100, 120, and 140 per minute. Recordings were repeated following intravenous administration of Dobutamine in doses of 5, 10, and 15 mug per kilogram per minute.

Haemodynamic effects of a new inotropic agent (dobutamine) in chronic cardiac failure.

The haemodynamic effects of dobutamine were studied in 14 patients with chronic congestive cardiac failure. Heart rate, central venous, pulmonary arterial, pulmonary wedge, and aortic pressures, aortic dp/dt, cardiac output, cardiac index, stroke volume, and pulmonary and systemic vascular resistances were measured or derived. Dose-response curves were obtained by recording all measurements before and after intravenous infusion of dobutamine at rates of 2.