Aortic stenosis and ACE inhibitors

Abstract

Niall Cox and co-workers (July 11, p 111)1Cox NLT Abdul-Hamid AR Mulley GP Why deny ACE inhibitors to patients with aortic stenosis?.Lancet. 1998; 352: 111-112Summary Full Text Full Text PDF PubMed Scopus (22) Google Scholar suggest that “vasodilatation is safe in patients with aortic stenosis”. However this statement is likely to be true only if the left venticle can increase flow adequately in response to a fall in peripheral vascular resistance. In some patinets with severe aortic stenosis and heart failure, left-ventricular ejection fraction does not increase during dobutamine infusion.2De Fillipi Willet DL Brickner ME et al.Usefulness of dobutamine echocardiography in distinguishing severe from nonsevere valvular aortic stenosis in patients with depressed left ventricular function and low transvalvular gradients.Am J Cardiol. 1995; 75: 191-194Summary Full Text PDF PubMed Scopus (286) Google Scholar Furthermore, transaortic flow increases less in response to dobutamine in patients with severe compared with moderate or mild aortic stenosis, even if left-ventricular systolic function is normal at rest.A proportion of patients with severe aortic stenosis have systemic hypertension,3Wren C Petch MC Calcific aortic stenosis.J R Coll Physicians Lond. 1983; 17: 192-195PubMed Google Scholar whereas in others the blood pressure is low. Vasodilators are unlikely to be safe in the latter group, especially since they tend to reduce the systemic blood pressure more than left-ventricular pressure with a consequent increase in transaortic gradient.4Bruckschlegel G Holmer S Jandeleit K et al.Blockade of the renin-angiotensin system in cardiac pressure-overload hypertrophy in rats.Hypertension. 1995; 25: 250-259Crossref PubMed Google ScholarEach case of aortic stenosis must be characterised not only by the degree of valvar obstruction, but also by left-ventricular, systemic, vascular, and clinical adaptations before deciding on therapy with angiotensin-converting-enzyme (ACE) inhibitors. Clinical experience is that ACE inhibitors can be harmful and should only be introduced under careful supervision of selected inpatients. We must not forget that the only definitive treatment for severe aortic stenosis is surgery. Niall Cox and co-workers (July 11, p 111)1Cox NLT Abdul-Hamid AR Mulley GP Why deny ACE inhibitors to patients with aortic stenosis?.Lancet. 1998; 352: 111-112Summary Full Text Full Text PDF PubMed Scopus (22) Google Scholar suggest that “vasodilatation is safe in patients with aortic stenosis”. However this statement is likely to be true only if the left venticle can increase flow adequately in response to a fall in peripheral vascular resistance. In some patinets with severe aortic stenosis and heart failure, left-ventricular ejection fraction does not increase during dobutamine infusion.2De Fillipi Willet DL Brickner ME et al.Usefulness of dobutamine echocardiography in distinguishing severe from nonsevere valvular aortic stenosis in patients with depressed left ventricular function and low transvalvular gradients.Am J Cardiol. 1995; 75: 191-194Summary Full Text PDF PubMed Scopus (286) Google Scholar Furthermore, transaortic flow increases less in response to dobutamine in patients with severe compared with moderate or mild aortic stenosis, even if left-ventricular systolic function is normal at rest. A proportion of patients with severe aortic stenosis have systemic hypertension,3Wren C Petch MC Calcific aortic stenosis.J R Coll Physicians Lond. 1983; 17: 192-195PubMed Google Scholar whereas in others the blood pressure is low. Vasodilators are unlikely to be safe in the latter group, especially since they tend to reduce the systemic blood pressure more than left-ventricular pressure with a consequent increase in transaortic gradient.4Bruckschlegel G Holmer S Jandeleit K et al.Blockade of the renin-angiotensin system in cardiac pressure-overload hypertrophy in rats.Hypertension. 1995; 25: 250-259Crossref PubMed Google Scholar Each case of aortic stenosis must be characterised not only by the degree of valvar obstruction, but also by left-ventricular, systemic, vascular, and clinical adaptations before deciding on therapy with angiotensin-converting-enzyme (ACE) inhibitors. Clinical experience is that ACE inhibitors can be harmful and should only be introduced under careful supervision of selected inpatients. We must not forget that the only definitive treatment for severe aortic stenosis is surgery.