{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T20:21:20Z","timestamp":1790194880863,"version":"4.1.0"},"reference-count":20,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"14_suppl_1","content-domain":{"domain":["www.ahajournals.org"],"crossmark-restriction":true},"short-container-title":["Circulation"],"published-print":{"date-parts":[[2008,9,30]]},"abstract":"<jats:p>\n                    <jats:bold>\n                      <jats:italic>Background\u2014<\/jats:italic>\n                    <\/jats:bold>\n                    Patients with low-flow, low-gradient aortic stenosis have a poor prognosis with conservative therapy but a high operative mortality if treated surgically. Recently, we proposed a new index of aortic stenosis severity derived from dobutamine stress echocardiography, the projected aortic valve area at a normal transvalvular flow rate, as superior to other conventional indices to differentiate true-severe from pseudosevere aortic stenosis. The objective of this study was to identify the determinants of survival, functional status, and change in left ventricular ejection fraction during follow-up of patients with low-flow, low-gradient aortic stenosis.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>\n                      <jats:italic>Methods and Results\u2014<\/jats:italic>\n                    <\/jats:bold>\n                    One hundred one patients with low-flow, low-gradient aortic stenosis (aortic valve area \u22641.2 cm\n                    <jats:sup>2<\/jats:sup>\n                    , left ventricular ejection fraction \u226440%, and mean gradient \u226440 mm Hg) underwent dobutamine stress echocardiography and an assessment of functional capacity using the Duke Activity Status Index. A subset of 72 patients also underwent a 6-minute walk test. Overall survival was 70\u00b15% at 1 year and 57\u00b16% at 3 years. After adjusting for age, gender, and the type of treatment (aortic valve replacement versus no aortic valve replacement), significant predictors of mortality during follow-up were a Duke Activity Status Index \u226420 (\n                    <jats:italic>P<\/jats:italic>\n                    =0.0005) or 6-minute walk test distance \u2264320 m (\n                    <jats:italic>P<\/jats:italic>\n                    &lt;0.0001, in the subset of 72 patients), projected aortic valve area at a normal transvalvular flow rate \u22641.2 cm\n                    <jats:sup>2<\/jats:sup>\n                    (\n                    <jats:italic>P<\/jats:italic>\n                    =0.03), and peak dobutamine stress echocardiography left ventricular ejection fraction \u226435% (\n                    <jats:italic>P<\/jats:italic>\n                    =0.03). More severe stenosis, defined as projected aortic valve area \u22641.2 cm\n                    <jats:sup>2<\/jats:sup>\n                    , was a predictor of mortality only in the no aortic valve replacement group. The Duke Activity Status Index, 6-minute walk test, and left ventricular ejection fraction improved significantly during follow-up in the aortic valve replacement group, but remained unchanged or decreased in the no aortic valve replacement group.\n                  <\/jats:p>\n                  <jats:p>\n                    <jats:bold>\n                      <jats:italic>Conclusion\u2014<\/jats:italic>\n                    <\/jats:bold>\n                    In patients with low-flow, low-gradient aortic stenosis, the most significant risk factors for poor outcome were (1) impaired functional capacity as measured by Duke Activity Status Index or 6-minute walk test distance; (2) more severe valve stenosis as measured by projected aortic valve area at a normal transvalvular flow rate; and (3) reduced peak stress left ventricular ejection fraction, a composite measure accounting for both resting left ventricular function and contractile reserve.\n                  <\/jats:p>","DOI":"10.1161\/circulationaha.107.757427","type":"journal-article","created":{"date-parts":[[2008,9,29]],"date-time":"2008-09-29T21:11:46Z","timestamp":1222722706000},"update-policy":"https:\/\/doi.org\/10.1161\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":192,"title":["Predictors of Outcomes in Low-Flow, Low-Gradient Aortic Stenosis"],"prefix":"10.1161","volume":"118","author":[{"given":"Marie-Annick","family":"Clavel","sequence":"first","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Fuchs","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ian G.","family":"Burwash","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gerald","family":"Mundigler","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean G.","family":"Dumesnil","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Helmut","family":"Baumgartner","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jutta","family":"Bergler-Klein","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rob S.","family":"Beanlands","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patrick","family":"Mathieu","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julien","family":"Magne","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philippe","family":"Pibarot","sequence":"additional","affiliation":[{"name":"From the Laval Hospital Research Center\/Que\u0301bec Heart Institute (M.A.C., C.F., J.M., J.G.D., P.M., P.P.), Laval University, Que\u0301bec, Canada; Vienna General Hospital (C.F., G.M., H.B., J.B.K.), Medical University of Vienna, Vienna, Austria; and the University of Ottawa Heart Institute (I.G.B., R.B.), Ottawa, Ontario, Canada."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","reference":[{"key":"e_1_3_3_1_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000079171.43055.46"},{"key":"e_1_3_3_2_2","doi-asserted-by":"publisher","DOI":"10.1161\/circulationaha.105.568824"},{"key":"e_1_3_3_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/S0002-9149(00)80078-8"},{"key":"e_1_3_3_4_2","doi-asserted-by":"publisher","DOI":"10.1161\/circulationaha.106.175132"},{"key":"e_1_3_3_5_2","doi-asserted-by":"publisher","DOI":"10.1161\/circulationaha.106.654210"},{"key":"e_1_3_3_6_2","doi-asserted-by":"publisher","DOI":"10.1016\/0002-9149(89)90496-7"},{"key":"e_1_3_3_7_2","doi-asserted-by":"publisher","DOI":"10.1378\/chest.110.2.325"},{"key":"e_1_3_3_8_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.101.7.765"},{"key":"e_1_3_3_9_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.101.16.1940"},{"key":"e_1_3_3_10_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000025611.21140.34"},{"key":"e_1_3_3_11_2","doi-asserted-by":"publisher","DOI":"10.1378\/chest.119.6.1766"},{"key":"e_1_3_3_12_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jacc.2007.10.067"},{"key":"e_1_3_3_13_2","doi-asserted-by":"publisher","DOI":"10.1161\/circ.95.9.2262"},{"key":"e_1_3_3_14_2","doi-asserted-by":"publisher","DOI":"10.1001\/archinte.160.9.1337"},{"key":"e_1_3_3_15_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000085167.67105.32"},{"key":"e_1_3_3_16_2","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCULATIONAHA.106.665018"},{"key":"e_1_3_3_17_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.jtcvs.2005.10.028"},{"key":"e_1_3_3_18_2","doi-asserted-by":"publisher","DOI":"10.1136\/hrt.2005.067363"},{"key":"e_1_3_3_19_2","doi-asserted-by":"publisher","DOI":"10.1136\/hrt.2006.102764"},{"key":"e_1_3_3_20_2","doi-asserted-by":"publisher","DOI":"10.1161\/01.cir.0000074211.28917.31"}],"container-title":["Circulation"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.ahajournals.org\/doi\/full\/10.1161\/CIRCULATIONAHA.107.757427","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,5,13]],"date-time":"2024-05-13T01:56:04Z","timestamp":1715565364000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.ahajournals.org\/doi\/10.1161\/CIRCULATIONAHA.107.757427"}},"subtitle":["Results of the Multicenter TOPAS Study"],"short-title":[],"issued":{"date-parts":[[2008,9,30]]},"references-count":20,"journal-issue":{"issue":"14_suppl_1","published-print":{"date-parts":[[2008,9,30]]}},"alternative-id":["10.1161\/CIRCULATIONAHA.107.757427"],"URL":"https:\/\/doi.org\/10.1161\/circulationaha.107.757427","relation":{},"ISSN":["0009-7322","1524-4539"],"issn-type":[{"value":"0009-7322","type":"print"},{"value":"1524-4539","type":"electronic"}],"subject":[],"published":{"date-parts":[[2008,9,30]]},"assertion":[{"value":"2008-09-30","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}