Aortic Stenosis Published Abstracts | |
Treatment decision in asymptomatic aortic valve stenosis: role of exercise testing.
OBJECTIVE: To determine the prognostic value of exercise testing, valve area, and maximum transaortic pressure gradient in asymptomatic patients with aortic valve stenosis.
SETTING: The outpatient service of a tertiary referral centre for cardiology.
DESIGN: Prospective clinical study.
PATIENTS: 66 consecutive patients with isolated severe aortic stenosis (aortic valve area ≤ 1.0 cm
2) were selected over a 58 month period. Mean (SD) follow up was 14.77 (11.93) Months.
INTERVENTIONS: At the initial visit Doppler echocardiography and exercise testing were performed to evaluate ST segment depression and the development of symptoms of aortic stenosis, ventricular arrhythmia, or inadequate rise of systolic blood pressure during exercise. Follow up clinical examinations were performed every three months thereafter to record the onset of symptoms.
MAIN OUTCOME MEASURES: Sudden death or the development of symptoms.
RESULTS: Eight patients developed dizziness during exercise testing but made a rapid and spontaneous recovery. No other complications of exercise testing occurred. Survival curves, with or without the occurrence of end point events for the variables studied, showed significant differences for positive versus negative exercise testing (p = 0.0001) and aortic valve area < 0.7 cm
2 v ≥ 0.7 cm
2 (p = 0.0021). There was no relation between the end points and transaortic gradient (p = 0.6882). In multivariate analysis, a hazard ratio of 7.43 was calculated for patients with a positive versus a negative exercise stress test. Although asymptomatic in daily life, 6% of the patients (4/66) experienced sudden death; all these had a positive exercise test and an aortic valve area of ≤ 0.6 cm
2.
CONCLUSIONS: Exercise testing is safe and is of prognostic value in asymptomatic patients with aortic stenosis.
PMID: 11559673 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).
SCOPE OF THE DOCUMENT: The guidelines attempt to deal with general issues of the treatment of patients with heart valve disorders, such as evaluation of patients with heart murmurs, prevention and treatment of endocarditis, management of valve disease in pregnancy, and treatment of patients with concomitant coronary artery disease (CAD), as well as more specialized issues that pertain to specific valve lesions. The guidelines focus primarily on valvular heart disease in the adult, with a separate section dealing with specific recommendations for valve disorders in adolescents and young adults. The diagnosis and management of infants and young children with congenital valvular abnormalities are significantly different from those of the adolescent or adult and are beyond the scope of these guidelines.
This task force report overlaps with several previously published ACC/AHA guidelines about cardiac imaging and diagnostic testing, including the guidelines for the clinical use of cardiac radionuclide imaging (1), the clinical application of echocardiography (2), exercise testing (3), and percutaneous coronary intervention (4). Although these guidelines are not intended to include detailed information covered in previous guidelines on the use of imaging and diagnostic testing, an essential component of this report is the discussion of indications for these tests in the evaluation and treatment of patients with valvular heart disease.
The committee emphasizes the fact that many factors ultimately determine the most appropriate treatment of individual patients with valvular heart disease within a given community. These include the availability of diagnostic equipment and expert diagnosticians, the expertise of interventional cardiologists and surgeons, and notably, the wishes of well-informed patients. Therefore, deviation from these guidelines may be appropriate in some circumstances. These guidelines are written with the assumptions that a diagnostic test can be performed and interpreted with skill levels consistent with previously reported ACC training and competency statements and ACC/AHA guidelines, that interventional cardiological and surgical procedures can be performed by highly trained practitioners within acceptable safety standards, and that the resources necessary to perform these diagnostic procedures and provide this care are readily available. This is not true in all geographic areas, which further underscores the committee’s position that its recommendations are guidelines and not rigid requirements.
PMID: 16875962 Which elderly patients with severe aortic stenosis benefit from surgical treatment? An aid to clinical decision making.
BACKGROUND AND AIM OF THE STUDY: Clinical decision-making in an individual elderly patient with severe aortic stenosis (AS) is difficult. The prognosis is influenced by increased age and various cardiac morbidity and comorbidity, and the benefit of surgery is uncertain because the prognosis with conservative treatment has rarely been described. The study aim was to identify those patients who would gain from surgical therapy.
METHODS: The long-term survival of a cohort of elderly patients after an initial diagnosis of severe aortic stenosis was analyzed. Multivariate analysis was used to develop patient profiles on the basis of four main variables of age, severity of AS, cardiac morbidity, and comorbidity, to illustrate the benefit of surgical treatment over conservative treatment.
RESULTS: A total of 280 consecutive patients aged > or = 70 years (median age 78 years) with a first-time diagnosis of isolated AS made between 1991 and 1993 was included. Of these patients, 120 underwent surgery. The seven-year predicted survival ranged from 6.9% to 83% in surgically treated patient, and from 0.6% to 48% in conservatively treated patients. The benefit of surgical treatment over conservative treatment was greatest in patients aged < 80 years, with a more critical AS, cardiac morbidity, and without (7-year survival 78% versus 14%) or with (7-year survival 56% versus 1%) comorbidity. Minimal benefit was seen in patients aged > 80 years with a less critical AS and without cardiac morbidity.
CONCLUSION: This model illustrated the benefit of surgical treatment over conservative treatment in 16 different profiles of elderly patients with severe AS. These findings may provide support for clinical decision making in individuals within this patient group.
PMID: 15222283 Outcome after aortic valve replacement in octogenarians.
BACKGROUND: The advancing age of the population in the western world and improvements in surgical techniques and postoperative care have resulted in an increasing number of very elderly patients undergoing cardiac operations. Therefore, the aim of this study is to evaluate the surgical outcome in 115 octogenarians after aortic valve replacement.
METHODS: We retrospectively identified 115 patients (47 men, 68 women) aged 82.3 +/- 2.1 years (mean, 80 to 92 years) who underwent aortic valve replacement alone (71 patients, 62.1%) or in combination with coronary artery bypass grafting (44 patients, 37.9%), between January 1992 and April 2003. These patients had significant severe aortic stenosis with a mean valve area of 0.62 +/- 0.15 cm
2 and a mean gradient of 88.62 +/- 24.06 mm Hg.
RESULTS: The in-hospital mortality rate was 8.5%. The late follow-up was 100% complete. Actuarial survival at 1 and 5 years was 86.4% and 69.4%, respectively. Predictors of late mortality were ejection fraction (p < 0.01), preoperative heart failure (p < 0.03), and the type of prosthesis (p < 0.03).
CONCLUSIONS: The outcome after aortic valve replacement in octogenarians is excellent; the operative risk is acceptable and the late survival rate is good. Therefore, cardiac surgery should not be withheld on the basis of age alone.
PMID: 15223409 Exercise testing to stratify risk in aortic stenosis.
AIMS: The aims of this study were to assess the accuracy of exercise testing in predicting symptom onset within 12 months in patients with asymptomatic aortic stenosis and to establish the criteria that define a positive test.
METHODS AND RESULTS: A total of 125 patients with aortic stenosis [effective orifice area (EOA) 0.9+/-0.2 cm
2] were assessed by Specific Activity Scale (SAS) classification, transthoracic echocardiography, and treadmill exercise testing using the modified Bruce protocol. During follow-up, 36 patients (29%) developed spontaneous symptoms within 12 months. Of these, 26 (72%) had had symptoms revealed by exercise testing and 24 (67%) had severe stenosis (EOA < or = 0.8 cm
2). Exercise-limiting symptoms were the only independent predictors of outcome at 12 months, and an abnormal blood pressure response or ST segment depression did not improve the accuracy of the exercise test. The positive predictive accuracy for exercise-induced symptoms was 57% in the whole population and 79% for patients aged <70 in SAS Class I. The negative predictive accuracy was 87% in the whole population and 86% in the subgroup.
CONCLUSION: A significant proportion of patients with apparently asymptomatic aortic stenosis experience limiting symptoms on treadmill exercise testing. The subsequent development of spontaneous symptoms is strongly related to the severity of stenosis and to limiting symptoms on exercise testing, but less so to an abnormal blood pressure response or ST segment depression.
PMID: 15820999 Spectrum of calcific aortic valve disease: pathogenesis, disease progression, and treatment strategies.
INTRODUCTION: Calcific aortic valve disease is a slowly progressive disorder with a disease continuum that ranges from mild valve thickening without obstruction of blood flow, termed aortic sclerosis, to severe calcification with impaired leaflet motion, or aortic stenosis. In the past, this process was thought to be “degenerative” because of time-dependent wear-and-tear of the leaflets with passive calcium deposition. Now, there is compelling histopathologic and clinical data suggesting that calcific valve disease is an active disease process akin to atherosclerosis with lipoprotein deposition, chronic inflammation, and active leaflet calcification. The overlap in the clinical factors associated with calcific valve disease and atherosclerosis and the correlation between the severity of coronary artery and aortic valve calcification provide further support for a shared disease process.
PMID: 15967862 Decision-making in elderly patients with severe aortic stenosis: why are so many denied surgery?
AIMS: To analyze decision-making in elderly patients with severe, symptomatic aortic stenosis (AS). METHODS AND RESULTS: In the Euro Heart Survey on valvular heart disease, 216 patients aged > or =75 had severe AS (valve area < or =0.6 cm
2/m
2 body surface area or mean gradient > or =50 mmHg) and angina or New York Heart Association class III or IV. Patient characteristics were analysed according to the decision to operate or not. A decision not to operate was taken in 72 patients (33%). In multivariable analysis, left ventricular (LV) ejection fraction [OR = 2.27, 95% CI (1.32-3.97) for ejection fraction 30-50, OR = 5.15, 95% CI (1.73-15.35) for ejection fraction < or =30 vs. >50%, P = 0.003] and age [OR = 1.84, 95% CI (1.18-2.89) for 80-85 years, OR=3.38, 95% CI (1.38-8.27) for > or =85 vs. 75-80 years, P = 0.008] were significantly associated with the decision not to operate; however, the Charlson comorbidity index was not [OR = 1.72, 95% CI (0.83-3.50), P = 0.14 for index > or =2 vs. <2]. Neurological dysfunction was the only comorbidity significantly linked with the decision not to operate.
CONCLUSION: Surgery was denied in 33% of elderly patients with severe, symptomatic AS. Older age and LV dysfunction were the most striking characteristics of patients who were denied surgery, whereas comorbidity played a less important role.
PMID: 16141261 Timing of aortic valve surgery.
INTRODUCTION: The timing of aortic valve surgery is described for patients presenting with two conditions: aortic stenosis and chronic aortic regurgitation.
PMID: 10908267 Valvular aortic stenosis: disease severity and timing of intervention.
BACKGROUND AND AIM OF THE STUDY: Standard echocardiographic evaluation of aortic stenosis (AS) severity includes measurement of aortic velocity, mean transaortic pressure gradient, and continuity equation valve area. Although these measures are adequate for decision making in most patients, there is no single value that defines severe stenosis. Aortic stenosis affects not just the valve, but the entire vascular system, including the left ventricle (LV) and systemic vasculature. More sophisticated measures of disease severity might explain the apparent overlap in hemodynamic severity between symptomatic and asymptomatic patients and might better predict the optimal timing of valve replacement. There have been several approaches to evaluation of stenosis severity based on valve hemodynamics, the ventricular response to increased afterload, ventricular-vascular coupling, or the systemic functional consequences of valve obstruction, such as exercise testing and serum brain natriuretic peptide levels. Aortic valve replacement is indicated when symptoms due to severe AS are present. In most asymptomatic patients, the risk of surgery is greater than the risk of watchful waiting so that management includes patient education, periodic echocardiography, and cardiac risk factor modification. Many adults with AS have comorbid conditions that affect both the diagnosis and management of the valve disease, including aortic regurgitation, aortic root dilation, hypertension, coronary artery disease, LV dysfunction, and atrial fibrillation. Comorbid conditions should be evaluated and treated based on established guidelines, although awareness of the potential effects of therapy in the presence of valve obstruction is needed.
PMID: 16750677 Outcome of 622 adults with asymptomatic, hemodynamically significant aortic stenosis during prolonged follow-up.
BACKGROUND: This study assessed the long-term outcome of a large, asymptomatic population with hemodynamically significant aortic stenosis (AS).
METHODS AND RESULTS: We identified 622 patients with isolated, asymptomatic AS and peak systolic velocity > or =4 m/s by Doppler echocardiography who did not undergo surgery at the initial evaluation and obtained follow-up (5.4+/-4.0 years) in all. Mean age (+/-SD) was 72+/-11 years; there were 384 (62%) men. The probability of remaining free of cardiac symptoms while unoperated was 82%, 67%, and 33% at 1, 2, and 5 years, respectively. Aortic valve area and left ventricular hypertrophy predicted symptom development. During follow-up, 352 (57%) patients were referred for aortic valve surgery and 265 (43%) patients died, including cardiac death in 117 (19%). The 1-, 2-, and 5-year probabilities of remaining free of surgery or cardiac death were 80%, 63%, and 25%, respectively. Multivariate predictors of all-cause mortality were age (hazard ratio [HR], 1.05; P<0.0001), chronic renal failure (HR, 2.41; P=0.004), inactivity (HR, 2.00; P=0.001), and aortic valve velocity (HR, 1.46; P=0.03). Sudden death without preceding symptoms occurred in 11 (4.1%) of 270 unoperated patients. Patients with peak velocity > or =4.5 m/s had a higher likelihood of developing symptoms (relative risk, 1.34) or having surgery or cardiac death (relative risk, 1.48).
CONCLUSIONS: Most patients with asymptomatic, hemodynamically significant AS will develop symptoms within 5 years. Sudden death occurs in approximately 1%/y. Age, chronic renal failure, inactivity, and aortic valve velocity are independently predictive of all-cause mortality.
PMID: 15956131 Should early elective surgery be performed in patients with severe but asymptomatic aortic stenosis?
INTRODUCTION: It has been well known for many years that symptomatic patients with severe aortic stenosis have a very poor outcome. Average survival after the onset of symptoms has been reported to be less than 2 to 3 years. In this situation, valve replacement not only results in dramatic symptomatic improvement but also in good long-term survival. This holds true even for patients with already reduced left ventricular function, as long as functional impairment is caused by aortic stenosis. There is general agreement that, in the absence of serious co-morbidity, surgery must be strongly recommended for patients with severe aortic stenosis who develop symptoms of congestive heart failure, exertional angina and dizziness or syncope during exercise.
In contrast, the management of asymptomatic patients with severe aortic stenosis remains a matter of controversy. Many cardiologists are reluctant to send asymptomatic patients for surgery while others are concerned about following these patients conservatively.
Because of the widespread use of Doppler echocardiography and because aortic valve replacement is offered regardless of age, cardiologists are increasingly faced with the difficult decision of whether to operate on these patients or not.
PMID: 12208221 Survival in elderly patients with severe aortic stenosis is dramatically improved by aortic valve replacement: Results from a cohort of 277 patients aged > or =80 years.
BACKGROUND: Calcific aortic stenosis (AS) is a disease of the elderly. However, there is reluctance to offer aortic valve replacement (AVR) for elderly patients with severe AS. We investigated if AVR confers a survival benefit in elderly patients with severe AS.
METHODS: We screened our echocardiographic database from 1993 to 2003 for patients with severe AS (AV area < or = 0.8 cm
2) and age > or = 80 years. Two hundred and seventy seven patients were identified. Complete chart reviews were performed for clinical data. Mortality data were obtained from National Death Index. Survival curves of patients who underwent AVR during the follow-up period were compared with those managed nonsurgically.
RESULTS: Patient characteristics were as follows: age 85+/-4 years, 53% male, AV area 0.68+/-0.16 cm2, EF 52+/-20%, CAD 47%, diabetes 17%. Over a mean follow-up of 2.5 years, 55 (20%) had AVR and there were 175 deaths. One-year, 2-year and 5-year survival rates among patients with AVR were 87, 78 and 68% respectively, compared with 52, 40 and 22%, respectively, in those who had no AVR (p < 0.0001). Hazard ratio for death with AVR adjusted for 19 covariates including age, EF, gender, comorbidities and pharmacotherapy was 0.38 (95% CI 0.26-0.66, p < 0.0001).
CONCLUSION: Prognosis of medically managed severe calcific AS in the elderly patients is dismal. AVR appears to improve survival of these patients and should be strongly considered in the absence of other major comorbidities.
PMID: 16950629