Management of chronic aortic regurgitation. From physician to surgeon

Abstract

The emphasis on the importance of the natural history of aortic regurgitation, discussed by Spagnuolo et al 1 in 1971 established the predictive criteria of clinical evolution and stimulated the development of reliable methods for follow-up of patients with aortic regurgitation.Since the decade of the ' 80s, the development of echocardiography has added imaging and other indices (for example, the so-called indices of ventricular function) 2-6 and perfected the tracing of the complex adaptive, ventricular remodeling.It is known that an increase in ventricular cavity size with a final diastolic volume of >150mL/m 2 or systolic diameter >70mm and an index of end systolic volume >60mL/m 2 or systolic diameter >55mm is associated with the imminent onset of symptoms. But should these indices be the decisive parameters used by the physician in deciding whether to refer the patient to the surgeon?Undoubtly, cardiac imaging data strengthen the decision about the best therapeutic approach for treating each phase of the natural history of aortic regurgitation, a complex 7 physiopathologic valvular heart disease, by associating volume and pressure overload. However, the indices of cardiac imaging obtained are not sufficient and may lead to errors in evaluation if not interpreted from a clinical point of view, because no reliable index for determining prognosis exists. For this, we should remember that the complexity of interaction between pre and afterload causes difficulties in the interpretation of left ventricular function as the exact representation of myocardial function.Values as high as 75mm diastolic diameter and 55mm systolic diameter were, in the early '80s, true, exact, accurate indicators of a worse postoperative prognosis. Presently they are seen in a significant percentage of good evolution, even as normal in the late postoperative period, due to the present efficiency of intraoperative myocardial protection. Still in the decade of the '80s, Carabello et al 8 questioned the isolated use of the so-called worse prognostic indices in patients with severe aortic regurgitation and left ventricular dysfunction. Of 14 patients with left ventricular dysfunction, according to the various indices described in the literature, 12 experienced improvement in symptoms, reduction in diameters, and increase in ejection fraction postoperatively which indicates that a systolic diameter >60mm correlated better with prognosis.It seems useful to go further than resting on evaluation by cardiac imaging alone, and whenever possible functional capacity and ventricular function should be evaluated through treadmill testing or isotonic exercises, coupled with radioisotopic ventriculography 9,10 . The total period of stress and the ejection fraction response are factors that give greater objectivity to the subjective determination of functional class obtained during anamnesis.However, contrary to that which occurs with other heart diseases , the retuction in left ventricular ejection fraction during exercise does not seem to mean intrins...