(Circulation. 2000;101:1940.)
© 2000 American Heart Association, Inc.
Clinical Investigation and Reports |
Severe Aortic Stenosis With Low Transvalvular Gradient and Severe Left Ventricular Dysfunction
Result of Aortic Valve Replacement in 52 Patients
From the Division of Cardiovascular Diseases and Internal Medicine (H.M.C., J.K.O., V.L.R., S.L.O., A.J.T.), the Section of Cardiovascular Surgery (H.V.S.), and the Section of Biostatistics (D.O.H.), Mayo Clinic and Mayo Foundation, Rochester, Minn.
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Abstract |
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Background—The outcome of aortic valve replacement in patients with severe aortic stenosis, low transvalvular gradient, and severe left ventricular dysfunction is not well known.
Methods and Results—Between 1985 and 1995, 52 patients with left
ventricular ejection fraction (EF) 
35% and aortic
stenosis with transvalvular mean gradient <30
mm Hg underwent aortic valve replacement. The mean (±SD) preoperative
characteristics included EF, 26±8%; aortic valve mean gradient,
23±4 mm Hg; aortic valve area, 0.7±0.2 cm2; and
cardiac output, 3.7±1.2 L/min. Simultaneous
coronary artery bypass graft surgery was performed in 32
patients (62%). Perioperative (30-day) mortality was
21% (11 of 52 patients). Ten additional patients died during
follow-up. Advanced age (P=0.048) and small aortic
prosthesis size (P=0.03) were significant
predictors of hospital mortality by univariate
analysis. By multivariate analysis, the
only predictor of surgical mortality was smaller prosthesis
size. The only predictor of postoperative survival was improvement in
postoperative functional class (P=0.04). Postoperative
functional improvement occurred in most patients. Postoperative EF was
assessed in 93% of survivors; 74% demonstrated improvement.
Positive change in EF was related to smaller preoperative aortic valve
area and female sex.
Conclusions—Despite severe left ventricular dysfunction, low transvalvular mean gradient, and increased operative mortality, aortic valve replacement was associated with improved functional status. Postoperative survival was related to younger patient age and larger aortic prosthesis size, and medium-term survival was related to improved postoperative functional class.
Key Words: prognosis • stenosis • valves • ventricles
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Introduction |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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Severe aortic stenosis carries a dismal prognosis when associated with congestive heart failure, with an expected survival of <2 years when treated medically.1 Aortic valve replacement is the only effective treatment, but the operative risk2 increases with the development of left ventricular (LV) systolic dysfunction.3 4 5 6 7
The results of aortic valve replacement are uncertain among patients with severe aortic stenosis, reduced LV ejection fraction (LVEF), and low transvalvular mean gradient. Although these patients represent <5% of patients with aortic stenosis, they also represent the most controversial subset. Increased perioperative risk and reduced late outcome compared with controls have been reported in patients with reduced LVEF.7 LV dysfunction may be secondary to long-standing severe aortic stenosis with superimposed myocardial fibrosis, extensive coronary artery disease, or prior myocardial infarction, and in this situation, the LV dysfunction is not likely to improve after aortic valve replacement. Some have therefore suggested that aortic valve replacement should not be considered in this subgroup of patients.8
Few data are available on the clinical outcome of patients with aortic
stenosis, decreased LVEF, and low transvalvular mean
gradient who undergo aortic valve replacement. Therefore, we tested the
hypothesis that aortic valve replacement in patients with aortic
stenosis, LVEF 35%, and transvalvular mean gradient
<30 mm Hg can be performed at an acceptable operative and
medium-term risk and that clinical and EF improvement occur in the
majority of surgical survivors.
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Methods |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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Study Population
From the Mayo Clinic surgical database, we identified all patients who had aortic valve replacement for native aortic stenosis in the presence of severe LV systolic dysfunction (EF
35%) and associated low transvalvular mean
gradient (mean gradient <30 mm Hg) between 1985 and 1995. We
previously reported the outcome of aortic valve replacement in patients
with aortic stenosis and reduced LVEF.7
Twenty-nine of the patients included in the present series were
included in our previous report. Patients were excluded if they had
concomitant valvular operations other than aortic valve
replacement, previous aortic valve replacement, or more than moderate
aortic valve regurgitation or were <18 years old.
Preoperative clinical, echocardiographic, cardiac
catheterization, hemodynamic,
coronary artery (Table 1
), and operative (Table 2) data were reviewed in 52 consecutive patients who fulfilled
entry criteria.
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Echocardiography
Comprehensive 2D and Doppler
echocardiographic assessment30 was
performed at the Mayo Clinic in 50 patients (96%) 30 days before
aortic valve replacement. The EF was calculated by 2D
echocardiography with a modification of the method
of Quinones et al10 11 in 17 patients, by the volumetric
method12 in 25 patients, and by visual
estimate13 14 in 10 patients.
Hemodynamic assessment of aortic stenosis was performed by 2D/Doppler methodology, and AVA was calculated by the continuity equation.15
Cardiac Catheterization
Forty patients (77%) had preoperative
hemodynamic assessment by cardiac
catheterization. With fluid-filled catheters, LV and
systemic arterial pressures were recorded
simultaneously. Cardiac output and index were measured, and
AVA was calculated from the Gorlin equation.16
Coronary angiography was performed in 50 patients (96%) (mean
age±SD, 72±9 years). Coronary artery stenosis was
defined as a luminal diameter narrowing of 
70% in 1 of the major
epicardial coronary arteries or 50% luminal diameter
narrowing of the left main coronary artery.
When >1 method was used to define preoperative EF, mean pressure
gradient, or AVA, the result of the echocardiographic
Doppler method was used when it was performed up to 30 days before
aortic valve replacement. The mean AVA (Table 1
) was obtained by
echocardiographic Doppler technique in 42 patients
and by cardiac catheterization in 10
patients.17
Surgical Procedures
The surgical data are outlined in Table 2.
Statistical Analysis
The data are reported as mean±SD. The relationship,
univariate and multivariate, of potential
risk factors with operative mortality (ie, death within 30 days
after operation) was assessed by logistic regression analysis.
Overall survival was estimated by the Kaplan-Meier method, and the
predictors were analyzed by the Cox proportional hazards model.
The relationship of preoperative variables to postoperative EF was
assessed by simple and multiple linear regression.
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Results |
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The preoperative clinical and hemodynamic data are outlined in Table 1
. The surgical
procedures and data are outlined in Table 2.
Clinical Outcome
Hospital Mortality
The 30-day mortality was 21% (11 of 52 patients).
Univariate analysis for operative mortality
identified 2 significant preoperative risk factors: a smaller
prosthesis size (P=0.03) and advanced
age at operation (P=0.048) (Table 3). The mean aortic prosthesis
size was 23.1±1.8 mm in survivors and 21.6±2.1 mm in
patients who died perioperatively. The mean age was
70±11 years for survivors and 77±8 years for patients who died
perioperatively. Multivariate
analysis identified prosthesis size as the only
predictor of hospital mortality. Body surface area was not
significantly related to hospital mortality.
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Overall Survival
Ten patients (Table 4) died during a
median follow-up of 1.5 years (up to 3.9 years). Two patients were lost
to follow-up. Two of the late deaths were from noncardiac causes. The
survival of this patient group was 62% at 3 years (Figure 1). The survival in the study group was
significantly lower (P=0.04) than survival among the 128
patients who underwent aortic valve replacement for aortic
stenosis, with mean gradient 30 mm Hg previously
reported.7
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The 3- and 5-year survival rates among patients without coronary artery disease were 71% compared with 58% and 29%, respectively, among patients with coronary artery disease (P=NS because of small sample size). This is in contrast to our previous report.7
The relationship between the number of perioperative
and late deaths and the preoperative mean gradient is outlined in Table 5.
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Symptomatic improvement was noted in most of the survivors
of surgery. Thirty patients had functional status noted before and
after operation. Of these, 85% were severely symptomatic
(NYHA class III or IV) before and only 23% were severely
symptomatic after operation (Figure 2): 77% of patients (23 of 30 patients)
improved by 1 NYHA functional class at follow-up. Twenty-three
patients (77%) were NYHA class I or II at follow-up.
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The year and urgency of operation as well as a history of coronary artery bypass graft surgery or myocardial infarction did not significantly affect survival in this series. Additional factors, including age, sex, preoperative EF, aortic valve area (AVA), cardiac output, mean aortic gradient, prosthesis size, and aortic annular patch enlargement, were not related to survival.
Postoperative EF
EF was assessed echocardiographically in 93% of
the 30-day survivors (38 of 41 patients) at a mean interval of 18
months after operation. Of the patients in whom LVEF was assessed after
operation, 28 (74%) showed a positive change. The mean change was an
increase of 10±14 EF units (P<0.001) (mean preoperative
EF, 24±7%; mean postoperative EF, 32±14%) (Figure 3). The postoperative EF ranged from 12%
to 65%. AVA was significantly related to a change in EF after
operation (P=0.03) (r=0.36). Sex was
significantly related to postoperative EF (P=0.009); women
had higher postoperative EF. There was no significant preoperative sex
difference in EF.
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Discussion |
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TopAbstractIntroductionMethodsResultsDiscussionReferences |
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In severe aortic stenosis, the left ventricle compensates for chronic pressure overload by hypertrophy in an attempt to normalize wall stress. Initially, EF and cardiac output are maintained. When wall stress exceeds the compensating mechanism, LV systolic function declines secondary to afterload mismatch, and the mean pressure gradient generated by the LV may be low despite the presence of severe aortic stenosis. Thus, when LV dysfunction is due to afterload mismatch,4 as seen in severe aortic stenosis, aortic valve replacement results in improvement in EF symptoms and survival.7
LV function and mean aortic valve gradient are prognostic indicators of
outcome among patients undergoing aortic valve replacement for aortic
stenosis.18 However, the outcome of aortic
valve replacement among patients with LV dysfunction and low
transvalvular mean gradient has not been well characterized.
These patients represent the most controversial and clinically
challenging patients with aortic stenosis. Two series reported
the outcome of aortic valve replacement in patients with low
transvalvular pressure gradient.19 20 However,
these 2 series combined described only 22 patients with
transvalvular mean gradient <30 mm Hg, and no EF data
were reported for 14 of them. When our present series was compared
with the 125 patients with aortic stenosis and reduced LVEF but
mean gradient >30 mm Hg previously reported,7 there
was a significant difference in survival (P=0.04) (Figure 1B). Thus, we undertook to define the outcome and to further
stratify risk in this group of patients.
The paucity of data on the outcome of aortic valve replacement in patients with aortic stenosis and LV dysfunction with low mean gradient led us to review 52 such patients in an attempt to determine perioperative mortality, overall survival, and predictors of outcome. By multivariate analysis, we found that 30-day mortality was related to aortic prosthesis size. All patients had LV dysfunction and low mean gradient; therefore, further EF and mean gradient analysis alone were not related to survival. Improved postoperative EF was related to preoperative AVA and female sex.
In the present study, smaller aortic prosthesis size was associated with increased surgical mortality, as previously reported.18 This remained an important predictor of perioperative survival even though 17% had undergone simultaneous aortic root enlargement to allow placement of a larger prosthesis. Of the 11 patients who died perioperatively, 5 received an aortic prosthesis <23 mm. There was no relationship between body surface area and perioperative mortality, but small prosthesis size reflects small annulus dimension. The body surface area of the patient who received the 17-mm aortic prosthesis was 1.32 m2, and the mean±SD of body surface area of the 3 patients who received 19-mm prostheses was 1.52±0.03 m2. Small valve prostheses have higher transvalvular gradients than larger prostheses.21 22 The failure to decrease afterload effectively with smaller aortic prostheses in these patients with low preoperative mean transvalvular gradient may influence surgical outcome.
The problem of valve-prosthesis–patient mismatch is also potentially important regarding this series of patients. The effective orifice area of a prosthesis is less than that of a normal human valve. Occasionally, the reduced prosthetic valve area further confounds the clinical situation, resulting in symptomatic and hemodynamic deterioration. This occurs when the decrease in afterload is less than expected because of small prosthesis size. This may account, in part, for the increased mortality noted among patients with the smallest prostheses.23 24
Small aortic prostheses have also been associated with increased late mortality among patients undergoing simultaneous coronary artery bypass graft surgery.25 This association was not appreciated among the patients we report.
It remains uncertain whether annular enlargement26 to accommodate a prosthesis 1 or 2 sizes larger will improve mortality.
Effect of Aortic Valve Replacement on Postoperative EF
Aortic valve replacement for aortic stenosis decreases
ventricular afterload.27 EF is expected to
improve after aortic valve replacement among patients with severe
aortic stenosis and decreased preoperative
EF.5 6 27 28 Those who do not improve probably have
permanent myocardial fibrosis. Previous studies showed that decreased
preoperative EF, previous myocardial infarction, and low preoperative
aortic valve gradient are associated with decreased postoperative
EF.29
An improvement in postoperative LVEF of 10 EF units (Figure 3)
was noted in our study. The relationship of sex differences in LV
adaptation to aortic stenosis has been
described.30 31 32 A substantial sex-associated difference
in regression of LV adaptation to chronic pressure and volume overload
has also been reported.18 The factors accounting for these
sex differences have not been characterized. The sex difference in our
series (improved postoperative EF in women) was an isolated sex-related
finding (ie, preoperative EF and mean gradient were not significantly
different between men and women). Excessive hypertrophy has
been reported in some patients with aortic
stenosis.31 32 This finding was not noted among
the 52 patients reported in this series.
Smaller preoperative AVA was significantly related to a change in postoperative EF. The smaller preoperative AVA may suggest a more severe degree of aortic stenosis in these patients with low preoperative mean gradient. Preoperative identification of appropriate surgical candidates may be improved by the use of dobutamine infusion33 and/or transesophageal imaging.34 These modalities may aid in optimizing surgical and overall survival.
An important variable that we were unable to assess was the true degree of aortic valve stenosis. Estimation of AVA in patients with low cardiac output and low transvalvular gradient is difficult, and in several patients in this series, the surgeon noted less than severe aortic stenosis at operation. Thus, some patients may have had another cause for LV dysfunction in conjunction with aortic valve stenosis of moderate severity. In our current practice, we use dobutamine during hemodynamic assessment; however, this was not performed in a sufficient number to allow risk stratification in the current series.
Limitations
Lack of Power
This series has limited power to stratify risk and identify
statistical predictors of outcome. However, no larger series of such
patients is available in the literature.
Follow-Up
The postoperative EF was determined for 93% of survivors of
surgery (38 of 41 patients). This should be considered in the
interpretation of results, because the performance of
echocardiography may have been an indicator for
better outcome. Comparison of baseline characteristics between
survivors with and without determination of postoperative EF indicated
no differences in proportion of female patients, preoperative NYHA
functional class, age, and percentage of patients with coronary
artery disease in this assessment.
EF Analysis
Echocardiographic estimates of LVEF may be a
cause for concern; the use of echocardiography in
this clinical setting, however, is standard clinical practice. Previous
studies from our institution and others have documented acceptable
correlations with angiography35 and have confirmed
reproducibility.36 37 38
Other Causes of LV Dysfunction
Causes of LV dysfunction related to factors other than aortic
stenosis and coronary artery disease cannot be excluded
in this patient population.
Lack of Control Group
All of the patients included in this study underwent aortic valve
replacement; thus, the clinical dilemma of differentiating LV
systolic dysfunction due to aortic stenosis from
moderate aortic stenosis with a coexistent
cardiomyopathic process cannot be addressed.
Cardiac Output Determination
Cardiac output determination may be unreliable when measured by
the thermodilution technique, particularly in low-output states. In our
series, however, only 6 of the 50 patients in whom cardiac output was
measured (12%) had measurement by thermodilution, so this technique
should not have adversely affected our data.
Dobutamine Hemodynamic Assessment
Intravenous administration of dobutamine
has been proposed as a method to determine surgical outcome in patients
with low-output low-gradient aortic stenosis, when there is
uncertainty about the severity of aortic
stenosis.33 Hemodynamic evaluation
during dobutamine infusion was not performed in enough
patients to allow risk stratification in this series.
Conclusions
Patients with low-gradient aortic stenosis
represent a small but controversial subset. In our patients
with decreased LVEF, low mean gradient, advanced age, and high
prevalence of coronary artery disease, surgical mortality was
lower than previously reported and was related to aortic
prosthesis size and patient age. The early and intermediate
follow-up results are acceptable compared with those of age- and
sex-matched controls. Marked improvement in symptoms and LVEF occurred
in >70% of the survivors. Improved postoperative EF was influenced
considerably by female sex and a small preoperative AVA. We submit that
patients with severe aortic stenosis, reduced LV function, and
low mean gradient, contrary to previous recommendations8
and despite increased operative mortality, should not be denied aortic
valve replacement, given the substantial potential clinical
benefit.
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Footnotes |
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Reprint requests to Heidi M. Connolly, MD, Mayo Clinic, 200 First St SW, Rochester, MN 55905.
Received September 9, 1999; revision received November 19, 1999; accepted December 2, 1999.
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 2006 WRITING COMMITTEE MEMBERS, R. O. Bonow, B. A. Carabello, K. Chatterjee, A. C. de Leon Jr, D. P. Faxon, M. D. Freed, W. H. Gaasch, B. W. Lytle, R. A. Nishimura, et al. 2008 Focused Update Incorporated Into the ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): Endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons Circulation, October 7, 2008; 118(15): e523 - e661. [Full Text] [PDF]
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 M. J. Silka and Y. Bar-Cohen Should patients with congenital heart disease and a systemic ventricular ejection fraction less than 30% undergo prophylactic implantation of an ICD?: Patients With Congenital Heart Disease and a Systemic Ventricular Ejection Fraction Less Than 30% Should Undergo Prophylactic Implantation of an Implantable Cardioverter Defibrillator Circ Arrhythm Electrophysiol, October 1, 2008; 1(4): 298 - 306. [Full Text] [PDF]
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M.-A. Clavel, C. Fuchs, I. G. Burwash, G. Mundigler, J. G. Dumesnil, H. Baumgartner, J. Bergler-Klein, R. S. Beanlands, P. Mathieu, J. Magne, et al. Predictors of Outcomes in Low-Flow, Low-Gradient Aortic Stenosis: Results of the Multicenter TOPAS Study Circulation, September 30, 2008; 118(14_suppl_1): S234 - S242. [Abstract] [Full Text] [PDF]
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R. O. Bonow, B. A. Carabello, K. Chatterjee, A. C. de Leon Jr, D. P. Faxon, M. D. Freed, W. H. Gaasch, B. W. Lytle, R. A. Nishimura, P. T. O'Gara, et al. 2008 Focused Update Incorporated Into the ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease) Endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons J. Am. Coll. Cardiol., September 23, 2008; 52(13): e1 - e142. [Full Text] [PDF]
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F. Levy, M. Laurent, J. L. Monin, J. M. Maillet, A. Pasquet, T. Le Tourneau, H. Petit-Eisenmann, M. Gori, Y. Jobic, F. Bauer, et al. Aortic Valve Replacement for Low-Flow/Low-Gradient Aortic Stenosis: Operative Risk Stratification and Long-Term Outcome: A European Multicenter Study J. Am. Coll. Cardiol., April 15, 2008; 51(15): 1466 - 1472. [Abstract] [Full Text] [PDF]
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T. Feldman and M. B. Leon Prospects for Percutaneous Valve Therapies Circulation, December 11, 2007; 116(24): 2866 - 2877. [Full Text] [PDF]
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J. Bergler-Klein, G. Mundigler, P. Pibarot, I. G. Burwash, J. G. Dumesnil, C. Blais, C. Fuchs, D. Mohty, R. S. Beanlands, Z. Hachicha, et al. B-Type Natriuretic Peptide in Low-Flow, Low-Gradient Aortic Stenosis: Relationship to Hemodynamics and Clinical Outcome: Results From the Multicenter Truly or Pseudo-Severe Aortic Stenosis (TOPAS) Study Circulation, June 5, 2007; 115(22): 2848 - 2855. [Abstract] [Full Text] [PDF]
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M. Mazzoni, R. De Maria, F. Bortone, M. Parolini, R. Ceriani, C. Solinas, V. Arena, and O. Parodi Long-Term Outcome of Survivors of Prolonged Intensive Care Treatment After Cardiac Surgery Ann. Thorac. Surg., December 1, 2006; 82(6): 2080 - 2087. [Abstract] [Full Text] [PDF]
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R. O. Bonow, B. A. Carabello, K. Chatterjee, A. C. de Leon Jr, D. P. Faxon, M. D. Freed, W. H. Gaasch, B. W. Lytle, R. A. Nishimura, P. T. O'Gara, et al. ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease) Developed in Collaboration With the Society of Cardiovascular Anesthesiologists Endorsed by the Society for Cardiovascular Angiography and Interventions and the Society of Thoracic Surgeons J. Am. Coll. Cardiol., August 1, 2006; 48(3): e1 - e148. [Full Text] [PDF]
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R. O. Bonow, B. A. Carabello, K. Chatterjee, A. C. de Leon Jr, D. P. Faxon, M. D. Freed, W. H. Gaasch, B. W. Lytle, R. A. Nishimura, P. T. O'Gara, et al. ACC/AHA 2006 Practice Guidelines for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease) Developed in Collaboration With the Society of Cardiovascular Anesthesiologists Endorsed by the Society for Cardiovascular Angiography and Interventions and the Society of Thoracic Surgeons J. Am. Coll. Cardiol., August 1, 2006; 48(3): 598 - 675. [Full Text] [PDF]
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P Pibarot and J G Dumesnil Prosthesis-patient mismatch: definition, clinical impact, and prevention Heart, August 1, 2006; 92(8): 1022 - 1029. [Abstract] [Full Text] [PDF]
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A. Kulik, I. G. Burwash, V. Kapila, T. G. Mesana, and M. Ruel Long-Term Outcomes After Valve Replacement for Low-Gradient Aortic Stenosis: Impact of Prosthesis-Patient Mismatch Circulation, July 4, 2006; 114(1_suppl): I-553 - I-558. [Abstract] [Full Text] [PDF]
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J. G. Dumesnil and P. Pibarot Prosthesis-patient mismatch and clinical outcomes: The evidence continues to accumulate J. Thorac. Cardiovasc. Surg., May 1, 2006; 131(5): 952 - 955. [Full Text] [PDF]
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R. A. Lange and L. D. Hillis Dobutamine Stress Echocardiography in Patients With Low-Gradient Aortic Stenosis Circulation, April 11, 2006; 113(14): 1718 - 1720. [Full Text] [PDF]
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J.-P. Quere, J.-L. Monin, F. Levy, H. Petit, S. Baleynaud, C. Chauvel, C. Pop, P. Ohlmann, C. Lelguen, P. Dehant, et al. Influence of Preoperative Left Ventricular Contractile Reserve on Postoperative Ejection Fraction in Low-Gradient Aortic Stenosis Circulation, April 11, 2006; 113(14): 1738 - 1744. [Abstract] [Full Text] [PDF]
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J. Chambers Low "gradient", low flow aortic stenosis. Heart, April 1, 2006; 92(4): 554 - 558. [Full Text] [PDF]
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D. P. Taggart Prosthesis patient mismatch in aortic valve replacement: possible but pertinent? Eur. Heart J., March 2, 2006; 27(6): 644 - 646. [Full Text] [PDF]
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P. A. Grayburn Assessment of Low-Gradient Aortic Stenosis With Dobutamine Circulation, February 7, 2006; 113(5): 604 - 606. [Full Text] [PDF]
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A. Chukwuemeka, V. Rao, S. Armstrong, J. Ivanov, and T. David Aortic valve replacement: a safe and durable option in patients with impaired left ventricular systolic function Eur. J. Cardiothorac. Surg., February 1, 2006; 29(2): 133 - 138. [Abstract] [Full Text] [PDF]
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H Baumgartner What influences the outcome of valve replacement in critical aortic stenosis? Heart, October 1, 2005; 91(10): 1254 - 1256. [Abstract] [Full Text] [PDF]
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B Vaquette, H Corbineau, M Laurent, B Lelong, T Langanay, C de Place, C Froger-Bompas, C Leclercq, C Daubert, and A Leguerrier Valve replacement in patients with critical aortic stenosis and depressed left ventricular function: predictors of operative risk, left ventricular function recovery, and long term outcome Heart, October 1, 2005; 91(10): 1324 - 1329. [Abstract] [Full Text] [PDF]
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P. A. Pellikka, M. E. Sarano, R. A. Nishimura, J. F. Malouf, K. R. Bailey, C. G. Scott, M. E. Barnes, and A. J. Tajik Outcome of 622 Adults With Asymptomatic, Hemodynamically Significant Aortic Stenosis During Prolonged Follow-Up Circulation, June 21, 2005; 111(24): 3290 - 3295. [Abstract] [Full Text] [PDF]
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H.-H. Sievers Prosthetic aortic valve replacement J. Thorac. Cardiovasc. Surg., May 1, 2005; 129(5): 961 - 965. [Full Text] [PDF]
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R. G. Fuster, J. A. M. Argudo, O. G. Albarova, F. H. Sos, S. C. Lopez, M. B. Codoner, J. A. B. Minano, and I. R. Albarran Patient-prosthesis mismatch in aortic valve replacement: really tolerable? Eur. J. Cardiothorac. Surg., March 1, 2005; 27(3): 441 - 449. [Abstract] [Full Text] [PDF]
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S. H. Rahimtoola The year in valvular heart disease J. Am. Coll. Cardiol., January 4, 2005; 45(1): 111 - 122. [Full Text] [PDF]
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W. C. Roberts and J. M. Ko Relation of weights of operatively excised stenotic aortic valves to preoperative transvalvular peak systolic pressure gradients and to calculated aortic valve areas J. Am. Coll. Cardiol., November 2, 2004; 44(9): 1847 - 1855. [Abstract] [Full Text] [PDF]
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B. A. Carabello Is it ever too late to operate on the patient with valvular heart disease? J. Am. Coll. Cardiol., July 21, 2004; 44(2): 376 - 383. [Abstract] [Full Text] [PDF]
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D. Messika-Zeitoun, M.-C. Aubry, D. Detaint, L. F. Bielak, P. A. Peyser, P. F. Sheedy, S. T. Turner, J. F. Breen, C. Scott, A. J. Tajik, et al. Evaluation and Clinical Implications of Aortic Valve Calcification Measured by Electron-Beam Computed Tomography Circulation, July 20, 2004; 110(3): 356 - 362. [Abstract] [Full Text] [PDF]
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U. C. Sharma, P. Barenbrug, S. Pokharel, W. R. M. Dassen, Y. M. Pinto, and J. G. Maessen Systematic review of the outcome of aortic valve replacement in patients with aortic stenosis Ann. Thorac. Surg., July 1, 2004; 78(1): 90 - 95. [Abstract] [Full Text] [PDF]
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E. H. Blackstone, D. M. Cosgrove, W.R. E. Jamieson, N. J. Birkmeyer, J. H. Lemmer Jr, D. C. Miller, E. G. Butchart, G. Rizzoli, M. Yacoub, and A. Chai Prosthesis size and long-term survival after aortic valve replacement J. Thorac. Cardiovasc. Surg., September 1, 2003; 126(3): 783 - 793. [Abstract] [Full Text] [PDF]
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C. Blais, J. G. Dumesnil, R. Baillot, S. Simard, D. Doyle, and P. Pibarot Impact of Valve Prosthesis-Patient Mismatch on Short-Term Mortality After Aortic Valve Replacement Circulation, August 26, 2003; 108(8): 983 - 988. [Abstract] [Full Text] [PDF]
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J.-L. Monin, J.-P. Quere, M. Monchi, H. Petit, S. Baleynaud, C. Chauvel, C. Pop, P. Ohlmann, C. Lelguen, P. Dehant, et al. Low-Gradient Aortic Stenosis: Operative Risk Stratification and Predictors for Long-Term Outcome: A Multicenter Study Using Dobutamine Stress Hemodynamics Circulation, July 22, 2003; 108(3): 319 - 324. [Abstract] [Full Text] [PDF]
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M. Rothenburger, K. Drebber, T. D.T. Tjan, C. Schmidt, C. Schmid, T. Wichter, H. H. Scheld, and M. Deiwick Aortic valve replacement for aortic regurgitation and stenosis, in patients with severe left ventricular dysfunction Eur. J. Cardiothorac. Surg., May 1, 2003; 23(5): 703 - 709. [Abstract] [Full Text] [PDF]
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S. H. Rahimtoola Choice of prosthetic heart valve for adult patients J. Am. Coll. Cardiol., March 19, 2003; 41(6): 893 - 904. [Abstract] [Full Text] [PDF]
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S. Bevilacqua, J. Gianetti, A. Ripoli, U. Paradossi, A. Giuseppe Cerillo, M. Glauber, M. L. Sacha Matteucci, M. Senni, A. Gamba, E. Quaini, et al. Aortic valve disease with severe ventricular dysfunction: stentless valve for better recovery Ann. Thorac. Surg., December 1, 2002; 74(6): 2016 - 2021. [Abstract] [Full Text] [PDF]
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J. F. Malouf, M. Enriquez-Sarano, P. A. Pellikka, J. K. Oh, K. R. Bailey, K. Chandrasekaran, C. J. Mullany, and A. J. Tajik Severe pulmonary hypertension in patients with severe aortic valve stenosis: clinical profile and prognostic implications J. Am. Coll. Cardiol., August 21, 2002; 40(4): 789 - 795. [Abstract] [Full Text] [PDF]
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P. A. Grayburn and E. J. Eichhorn Dobutamine Challenge for Low-Gradient Aortic Stenosis Circulation, August 13, 2002; 106(7): 763 - 765. [Full Text] [PDF]
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R. A. Nishimura, J. A. Grantham, H. M. Connolly, H. V. Schaff, S. T. Higano, and D. R. Holmes Jr Low-Output, Low-Gradient Aortic Stenosis in Patients With Depressed Left Ventricular Systolic Function: The Clinical Utility of the Dobutamine Challenge in the Catheterization Laboratory Circulation, August 13, 2002; 106(7): 809 - 813. [Abstract] [Full Text] [PDF]
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J. J. Pereira, M. S. Lauer, M. Bashir, I. Afridi, E. H. Blackstone, W. J. Stewart, P. M. McCarthy, J. D. Thomas, and C. R. Asher Survival after aortic valve replacement forsevere aortic stenosis with low transvalvular gradients and severe left ventricular dysfunction J. Am. Coll. Cardiol., April 17, 2002; 39(8): 1356 - 1363. [Abstract] [Full Text] [PDF]
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B. A. Carabello Ventricular function in aortic stenosis: how low can you go? J. Am. Coll. Cardiol., April 17, 2002; 39(8): 1364 - 1365. [Full Text] [PDF]
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B. A. Carabello Evaluation and Management of Patients With Aortic Stenosis Circulation, April 16, 2002; 105(15): 1746 - 1750. [Full Text] [PDF]
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S. F. Khuri Evidence, sources, and assessment of injury during and following cardiac surgery Ann. Thorac. Surg., December 1, 2001; 72(6): S2205 - 2207. [Full Text] [PDF]
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J.-L. Monin, M. Monchi, V. Gest, A.-M. Duval-Moulin, J.-L. Dubois-Rande, and P. Gueret Aortic stenosis with severe left ventricular dysfunction and low transvalvular pressure gradients: Risk stratification by low-dose dobutamine echocardiography J. Am. Coll. Cardiol., June 15, 2001; 37(8): 2101 - 2107. [Abstract] [Full Text] [PDF]
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S. H Rahimtoola VALVE DISEASE: Should patients with asymptomatic mild or moderate aortic stenosis undergoing coronary artery bypass surgery also have valve replacement for their aortic stenosis? Heart, March 1, 2001; 85(3): 337 - 341. [Full Text]
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S. H. Rahimtoola Severe Aortic Stenosis With Low Systolic Gradient : The Good and Bad News Circulation, April 25, 2000; 101(16): 1892 - 1894. [Full Text] [PDF]
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