Prognostic significance of preoperative left ventricular ejection fraction and valve lesion in patients with aortic valve replacement

2023 Korean Society of Echocardiography position paper for diagnosis and management of valvular heart disease, part I: aortic valve disease

This manuscript represents the official position of the Korean Society of Echocardiography on valvular heart diseases. This position paper focuses on the clinical management of valvular heart diseases with reference to the guidelines recently published by the American College of Cardiology/American Heart Association and the European Society of Cardiology. The committee tried to reflect the recently published results on the topic of valvular heart diseases and Korean data by a systematic literature search based on validity and relevance. In part I of this article, we will review and discuss the current position of aortic valve disease in Korea.

Impact of Left Ventricular Ejection Fraction on Clinical Outcomes in Bicuspid Aortic Valve Disease

BACKGROUND

The prognostic impact of left ventricular ejection fraction (LVEF) in patients with bicuspid aortic valve (BAV) disease has not been previously studied.

OBJECTIVES

The purpose of this study was to determine the prognostic impact of LVEF in BAV patients according to the type of aortic valve dysfunction.

METHODS

We retrospectively analyzed the data collected in 2,672 patients included in an international registry of patients with BAV. Patients were classified according to the type of aortic valve dysfunction: isolated aortic stenosis (AS) (n = 749), isolated aortic regurgitation (AR) (n = 554), mixed aortic valve disease (MAVD) (n = 190), or no significant aortic valve dysfunction (n = 1,179; excluded from this analysis). The study population was divided according to LVEF strata to investigate its impact on clinical outcomes.

RESULTS

The risk of all-cause mortality and the composite endpoint of aortic valve replacement or repair (AVR) and all-cause mortality increased when LVEF was <60% in the whole cohort as well as in the AS and AR groups, and when LVEF was <55% in MAVD group. In multivariable analysis, LVEF strata were significantly associated with increased rate of mortality (LVEF 50%-59%: HR: 1.83 [95% CI: 1.09-3.07]; P = 0.022; LVEF 30%-49%: HR: 1.97 [95% CI: 1.13-3.41]; P = 0.016; LVEF <30%: HR: 4.20 [95% CI: 2.01-8.75]; P < 0.001; vs LVEF 60%-70%, reference group).

CONCLUSIONS

In BAV patients, the risk of adverse clinical outcomes increases significantly when the LVEF is <60%. These findings suggest that LVEF cutoff values proposed in the guidelines to indicate intervention should be raised from 50% to 60% in AS or AR and 55% in MAVD.

Utility of dobutamine stress echocardiography in aortic valve regurgitation and reduced left ventricular function

OBJECTIVE

Predictors for post-operative reverse remodeling in patients with severe aortic regurgitation (AR) and reduced left ventricular ejection fraction (LVEF) are unknown. We performed low-dose dobutamine stress echocardiography (DSE) in patients with severe AR and reduced LVEF to evaluate the relationship between contractile reserve (CR) and reverse remodeling after surgery.

METHODS

In 31 patients with chronic severe AR and reduced LVEF (LVEF < 50%), we performed pre-operative DSE, assessed CR, and examined whether changes in preoperative DSE were associated with improvement of post-operative LVEF after aortic valve surgery.

RESULTS

The pre-operative echocardiographic findings were as follows: left ventricular (LV) end-diastolic dimension: 67 ± 10 mm, LV end-systolic dimension: 52 ± 13 mm, and LVEF: 42 ± 8%. All patients underwent aortic valve surgery. Patients with pre-operative LVEF of ≥45% exhibited a significant increase in LVEF; however, patients with pre-operative LVEF of <45% showed no significant change. When we examined the results of DSE performed in patients with pre-operative LVEF of <45%, ΔLVEF of ≥6% (with CR) during DSE was related to an improvement in post-operative LVEF; ΔLVEF of ≥6% during DSE predicted an improvement in post-operative LVEF, with sensitivity 100%; specificity 78%; and area under curve (AUC) .92.

CONCLUSIONS

DSE might be a helpful tool for predicting post-operative reverse remodeling in patients with severe AR and moderately reduced LVEF.

Clinical and Echocardiographic Results of Aortic Valve Replacement in the Failing Ventricle: Do Aortic Stenosis and Aortic Regurgitation Differ?

BACKGROUND

We hypothesized that long-term clinical and echocardiographic recovery of the impaired ventricle from pressure (aortic stenosis [AS]) and volume (aortic regurgitation [AR]) overload would be different after aortic valve replacement (AVR).

METHODS

We compared the results of AVR in patients with a preoperative ejection fraction (EF) of 0.35 or less due to AS, AR, or mixed disease. We constructed a mixed-effects model of EF and left ventricular (LV) end-diastolic diameter (LVEDD) to understand ventricular recovery over the short- (in-hospital), intermediate- (3-6 months), and longer- (>24 months) terms. We sought to identify factors associated with clinical and echocardiographic recovery using multivariable analysis.

RESULTS

Between July 2011 and 2017, 136 patients with a preoperative EF of 0.35 or less and severe AS (n = 83), severe AR (n = 18), or mixed AS and AR (n = 35) underwent AVR. There were 2 (1.5%) early deaths in the AS group. Survival at 1, 2, and 5 years did not differ between groups. Baseline EF did not differ between the groups but improved with markedly different trajectory and time course in the AS, AR, and mixed groups over time. LVEDD regressed in all patient cohorts, following a different pattern for AS and AR. Baseline EF and LVEDD predicted the long-term fate of the LV but did not determine survival. We identify factors associated with long-term survival.

CONCLUSIONS

The pattern of LV recovery appears to be early in AS and delayed in AR. Baseline clinical factors, rather than echocardiographic status of the LV, appear to determine late survival.

Optimal Management of Chronic Severe Aortic Regurgitation - How to Determine Cutoff Values for Surgical Intervention?

Aortic regurgitation (AR) is a common valvular heart disease, but the optimal timing of surgical intervention remains controversial. In the natural history of chronic severe AR, sudden death is rare, and the annual mortality rate is comparatively low. Considering the hemodynamic features of combined volume and pressure overload and long-term compensation in patients with chronic AR, symptoms related to AR do not frequently occur. Therefore, the progression of left ventricular (LV) dysfunction is a key factor in determining the timing of surgical intervention in patients with severe chronic AR. In addition to symptoms, an ejection fraction <50% and an LV endsystolic diameter (LVESD) >45 mm are appropriate cutoff values for surgical intervention in Japanese patients, whereas LV end-diastolic diameter is not a good indicator. An LVESD index of 25 mm/m²is controversial, because adjusting for body size may cause overcorrection in Japanese patients who have a small body size compared with Westerners. Accumulation of data from the Japanese population is indispensable for establishing guidelines on optimal management of patients with chronic AR.

2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the valvular heart disease guideline provides recommendations for clinicians to diagnose and manage valvular heart disease as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to March 1, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, Cochrane, Agency for Healthcare Research and Quality Reports, and other selected database relevant to this guideline. Structure: Many recommendations from the earlier valvular heart disease guidelines have been updated with new evidence and provides newer options for diagnosis and treatment of valvular heart disease. This summary includes only the recommendations from the full guideline which focus on diagnostic work-up, the timing and choice of surgical and catheter interventions, and recommendations for medical therapy. The reader is referred to the full guideline for graphical flow charts, text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in developing these guidelines.

Early Valve Replacement for Severe Aortic Valve Disease: Effect on Mortality and Clinical Ramifications

Timing of aortic valve intervention for chronic aortic regurgitation (AR) and/or aortic stenosis (AS) potentially affects long-term survival. The 2014 American Heart Association/American College of Cardiology (AHA/ACC) guidelines provide recommendations for the timing of intervention. Subsequent to the guidelines' release, several studies have been published that suggest a survival benefit from earlier timing of surgery for severe AR and/or AS. The aim of this review was to determine whether patients who have chronic aortic regurgitation (AR) and/or aortic stenosis (AS) have a survival benefit from earlier timing of aortic valve surgery. Medical databases were systematically searched from January 2015 to April 2020 for randomized controlled trials (RCTs) and observational studies that examined the timing of aortic valve replacement surgery for chronic AR and/or AS. For chronic AR, four observational studies and no RCTs were identified. For chronic AS, five observational studies, one RCT and one meta-analysis were identified. One observational study examining mixed aortic valve disease (MAVD) was identified. All of these studies, for AR, AS, and MAVD, found long-term survival benefit from timing of aortic valve surgery earlier than the current guidelines. Larger prospective RCTs are required to evaluate the benefit of earlier surgical intervention.

Predictors of Long-Term Outcome of Isolated Surgical Aortic Valve Replacement in Aortic Regurgitation With Reduced Left Ventricular Ejection Fraction and Extreme Left Ventricular Dilatation

The management of severe aortic regurgitation (AR) in patients with reduced left ventricular function and extreme left ventricular dilatation presents a therapeutic dilemma. This study aims to assess risk factors of aortic valve replacement (AVR) for these particular population based on its performances. Two hundred twelve severe AR patients accompanied by left ventricular ejection fraction (LVEF) <50% and left ventricular end-diastolic dimension (LVEDD) ≥70 mm who underwent isolated AVR between January 2007 and December 2016 were identified retrospectively. Logistic regression and receiver operating characteristic were used to analyze prognostic indicators for in-hospital mortality while Kaplan-Meier analysis for long-term survival. Mean age was 56 ± 13 years with mean LVEF 40 ± 7% and LVEDD 78 ± 6 mm. In-hospital mortality rate was 7%, and survival rates at 5 and 10 years were 88 ± 4% and 73 ± 10%, respectively. Logistic regression analysis indicated in-hospital mortality was associated with preoperative age and LVEF. Receiver operating characteristic analysis showed LVEF = 35% was the best cut-off value at which to predict in-hospital death. Kaplan-Meier analysis revealed patients with markedly reduced LV function (LVEF <35%) had lower survival rates compared with other patients with moderate LV dysfunction (LVEF 36% to 50%) (1-, 5-, and 10-year: 90 ± 4%, 64 ± 7%, and 55 ± 14%, vs 97 ± 1%, 94 ± 3%, and 76 ± 7%, p <0.001). An age-matched analysis showed similar trend (p = 0.020). In Conclusion, AVR may be unsafe for severe AR patients with markedly reduced LV function (LVEF <35%) and extreme left ventricular dilatation (LVEDD >70 mm) due to poor postoperative early- and long-term outcomes.

Changes in left ventricular function in patients with aortic regurgitation 12 months after transapical transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is an established treatment for high surgical risk aortic stenosis patients; in recent years, it has also been used in patients with pure/dominant aortic regurgitation (AR). This study aimed to determine the impact of transapical TAVI on left ventricle myocardial mechanics in AR patients. Thirty AR patients (70% men; mean age, 72.8 ± 4.3 years) were enrolled. Conventional echocardiography was performed on all patients before and 12 months after TAVI. Three-dimensional speckle tracking was accomplished in 20 AR patients for the evaluation of global longitudinal strain, global circumferential strain, twist, torsion, apical rotation and basal rotation. Preoperative left ventricular ejection fraction (LVEF), global longitudinal strain (GLS), global circumferential strain (GCS), twist, torsion and apical rotation were impaired in AR patients compared with controls. Mean left ventricular (LV) end-diastolic diameter (from 62.9 ± 7.3 to 52.0 ± 6.8 mm, p < 0.001), LV end-diastolic volume (from 199.4 ± 55.0 to 130.1 ± 48.9 mL, p < 0.001), and LV mass index (179.8 ± 52.2-134.4 ± 42.5 g/m², p = 0.001) decreased 12 months after TAVI. Interestingly, GLS (from - 17.2 ± 3.2 to - 18.9 ± 3.7, p = 0.007) and GCS (from - 23.9 ± 4.9 to - 25.7 ± 5.0, p = 0.008) improved significantly, but LVEF did not significantly improve. In terms of the rotational mechanics, twist, rotation and basal rotation remained almost unchanged, whereas apical rotation (from 7.4 ± 4.0 to 5.5 ± 3.9, p = 0.009) was significantly impaired after transapical TAVI. Our results indicate that LV function was improved in terms of myocardial deformation but worsened in terms of apical rotation 12 months after TAVI in AR patients. Three-dimensional speckle tracking echocardiography appears to be a sensitive method for detecting subtle cardiac remodeling after TAVI.

Survival after Aortic Valve Replacement for Aortic Regurgitation: Prediction from Preoperative Contractility Measurement

BACKGROUND

Noninvasive measurement of myocardial contractility (end-systolic wall stress-adjusted change in left ventricular ejection fraction from rest to exercise [ΔLVEF - ΔESS]) predicts heart failure, subnormal LVEFrest, and sudden death in asymptomatic patients with chronic severe aortic regurgitation (AR). Here we assess the relation of preoperative ΔLVEF - ΔESS to survival after aortic valve replacement (AVR).

METHODS

Patients who underwent AVR for chronic, isolated, pure severe AR (n = 66) were followed for 13.0 ± 6.4 event-free years. Preoperative ΔLVEF - ΔESS (from combined echocardiographic and radionuclide cineangiographic data) enabled cohort stratification into 3 terciles (-1 to -11% [normal or mild] contractility deficit, -12 to -16% [moderate], and ≤-17% [severe], identical with segregation in our earlier study) to relate preoperative contractility to postoperative survival and to age- and gender-matched US census data.

RESULTS

Since AVR, 22 patients died (average annual risk [AAR] for all-cause mortality for the entire co hort = 3.15%). Preoperative ΔLVEF - ΔESS predicted postoperative survival (p = 0.009, log rank test). By contractility terciles, all-cause AARs were 1.44, 2.58, and 6.40%. Survival was lower than among US census comparators (p < 0.02), but the "mild" tercile was indistinguishable from census data (p = ns). By multivariable Cox regression, survival prediction by pre-AVR ΔLVEF - ΔESS was independent of, and superior to, prediction by age at surgery, gender, preoperative functional class, LVEFrest, LVEFexercise, change in LVEFrest to exercise, and LV diastolic or systolic dimensions (p ≤ 0.01, pre-AVR ΔLVEF - ΔESS vs. other covariates).

CONCLUSION

In severe AR, preoperative contractility predicts post-AVR survival and may be prognostically superior to clinical, geometric and performance descriptors, potentially impacting on patient selection for surgery.

Aortic valve replacement associated with survival in severe regurgitation and low ejection fraction

OBJECTIVES

Although guidelines support aortic valve replacement (AVR) in patients with severe aortic regurgitation (AR) and left ventricular ejection fraction (LVEF) <50%, severe left ventricular dysfunction (LVEF <35%) is thought to confer high surgical risk. We sought to determine if a survival benefit exists with AVR compared with medical management in this high-risk, relatively rare population.

METHODS

A large institutional echocardiography database was queried to identify patients with severe AR and LVEF <35%. Manual chart review was performed. Due to small sample size and population heterogeneity, corrected group prognosis method was applied, which calculates the adjusted survival curve for each individual using fitted Cox proportional hazard model. Average survival adjusted for comorbidities and age was then calculated using the weighted average of the individual survival curves.

RESULTS

Initially, 2 54 614 echocardiograms were considered, representing 1 45 785 unique patients, of which 40 patients met inclusion criteria. Of those, 18 (45.0%) underwent AVR and 22 (55.0%) were managed medically. Absolute mortality was 27.8% in the AVR group and 91.2% in the medical management group. After multivariate adjustment, end-stage renal disease (HR=17.633, p=0.0335) and peripheral arterial disease (HR=6.050, p=0.0180) were associated with higher mortality. AVR was associated with lower mortality (HR=0.143, p=0.0490). Mean follow-up time of the study cohort was 6.58 years, and mean survival for patients undergoing AVR was 6.31 years.

CONCLUSIONS

Even after adjustment for clinical characteristics and patient age, AVR is associated with higher survival for patients with low LVEF and severe AR. Although treatment selection bias cannot be completely eliminated by this analysis, these results provide some evidence that surgery may be associated with prolonged survival in this high-risk patient group.

Current Management of Patients with Severe Aortic Regurgitation

OPINION STATEMENT

Chronic aortic regurgitation can result from various congenital and acquired anomalies and can be associated with proximal aortic disease. As the number of aortic valve procedures is growing, the incidence of post-procedural regurgitation also increases with associated morbidity. Typical evolution is characterized by a clinically silent phase of variable duration followed by a rather rapid decline with high incidence of adverse events. A challenge remains to find the optimal timing for an intervention: Patients are exposed to unnecessary surgical risks if treated prematurely, but peri- and post-operative prognosis is worse when the intervention is performed too late. Clinical evaluation and serial imaging tests can optimize the timing for intervention. Clinical follow-up should try to elucidate associated symptoms, with quantitative measurement of functional capacity as needed. Serial imaging examinations are required to identify sub-clinical left ventricular dysfunction or severe dilatation that should prompt a surgery. At least in selected cases, newer imaging modalities (MRI, 3D echocardiography) and/or biomarkers can help for the management of these patients, and more research is needed to determine if their systematic use can be beneficial. Medical treatment with vasodilators and anti-remodeling drugs can be helpful in some patients but should not replace or delay aortic valve surgery when indicated. Most patients will eventually be treated with surgical aortic valve replacement. Although possible in selected cases, transcatheter aortic valve replacement is not commonly used for patients with pure aortic regurgitation. For patients with prior aortic valve replacement and aortic regurgitation (paravalvular or intravalvular), emerging percutaneous approaches can be considered when available, especially for those at high surgical risk.

Value of three-dimensional speckle-tracking in detecting left ventricular dysfunction in patients with aortic valvular diseases

BACKGROUND

The aim of this study was to investigate the value of three-dimensional speckle-tracking echocardiography for the detection of subclinical left ventricular dysfunction in patients with aortic valvular disease (AVD).

METHODS

Fifty-nine patients with AVD in New York Heart Association functional class I or II as well as 48 controls were recruited. Patients with AVD were divided further into those with aortic stenosis (AS; n = 34) and those with aortic regurgitation (AR; n = 25). All patients underwent conventional echocardiography and three-dimensional speckle-tracking echocardiography.

RESULTS

Analysis of variance showed global longitudinal strain to be compromised in the AR group (-16.9% vs -19.3%, P = .015) and more dramatically decreased in the AS group (-14.3% vs -19.3%, P < .001) compared with healthy controls. Impairment of global circumferential strain was observed in patients with AR (-15.9% vs -18.5%, P = .009) but not in those with AS (-18.2% vs -18.5%, P = .768). Global area strain and global radial strain were decreased in patients with AS and those with AR compared with controls, but the difference between the two subgroups was not significant.

CONCLUSIONS

Strains measured by three-dimensional speckle-tracking echocardiography are useful indices of early-stage heart dysfunction caused by AVD. Longitudinal strain is more vulnerable to pressure overload caused by AS, whereas circumferential strain is more sensitive to volume overload due to AR.

[Surgery of aortic regurgitation with reduced left ventricular function]

BACKGROUND

Aortic valve replacement improves clinical symptoms and left ventricular systolic function in patients with chronic aortic regurgitation despite a higher surgical risk. The objective of this study is to determine if left ventricular function will be normalized after surgery.

PATIENTS AND METHOD

This retrospective study included 40 patients (nine females and 31 males) with chronic aortic regurgitation and left ventricular systolic dysfunction who were evaluated by echocardiography Doppler. Were included patients with left ventricular ejection fraction less or equal to 45%. Ages ranged from 18 to 77 years (mean = 46.4 ± 12.6 years). Preoperatively, six patients (15%) were asymptomatic, ten (25%) were in NYHA II, half (50%) in NYHA III and four (10%) in NYHA IV. The mean preoperative ejection fraction (EF) was 36.2 ± 2%. The mean end systolic and diastolic dimensions were 61.7 ± 8.5 mm and 78.9 ± 9.7 mm respectively. Aortic regurgitation was quantified grade III in sixteen patients (40%) and grade IV in twenty-four (60%).

RESULTS

Thirty-seven patients underwent aortic valve replacement and three Bentall operations. Hospital mortality was 7.5% (3/40). The mean follow-up period was 69.7 months. All survivor patients were investigated. Out of these, five were lost and 32 were controlled. Symptomatic improvement was noted in most of the survivors. Sixty percent (24/40) were severely symptomatic before and only 6.25% (2/32) during follow-up. The ejection fraction increased significantly after surgery (36.2 ± 2% in preoperative period vs. 55.2 ± 10% in postoperative period, P < 0.02). Left ventricular diameters decreased significantly also. Survival rates were 3-year 94%, 5-year 91% and 7-year 89%.

CONCLUSION

Despite reduced left ventricular systolic function, aortic valve replacement in chronic aortic regurgitation was associated with acceptable operative risk. Surgery improves functional status, symptoms and ejection fraction in most patients.

Aortic valve and ascending aorta guidelines for management and quality measures: executive summary

The Society of Thoracic Surgeons Clinical Practice Guidelines are intended to assist physicians and other health care providers in clinical decision making by describing a range of generally acceptable approaches for the diagnosis, management, or prevention of specific diseases or conditions. These guidelines should not be considered inclusive of all proper methods of care or exclusive of other methods of care reasonably directed at obtaining the same results. Moreover, these guidelines are subject to change over time, without notice. The ultimate judgment regarding the care of a particular patient must be made by the physician in light of the individual circumstances presented by the patient.

Effect of preoperative ejection fraction, left ventricular systolic dimension and hemoglobin level on survival after aortic valve surgery in patients with severe chronic aortic regurgitation

Surgical indications in patients with severe chronic aortic regurgitation (AR) and normal left ventricular (LV) ejection fractions (EF) remain to be established. The aim of this study was to identify prognostic indicators after surgery in patients with severe AR and normal LV systolic function. Preoperative clinical and echocardiographic characteristics were evaluated in 284 consecutive patients with chronic severe AR who underwent aortic valve surgery. Of these patients, 169 had normal (≥50%) and 115 had depressed (<50%) preoperative LV EFs. All-cause mortality was observed for a median of 39.9 months. Of 284 patients, 7 (4.4%) with normal LV EFs and 15 (12.0%) with depressed LV EFs died during follow-up after aortic valve surgery (p = 0.017). In patients with normal EFs, multivariate Cox regression analysis showed that large LV end-systolic dimension and low plasma hemoglobin level were independent predictors of postsurgical mortality. Receiver-operating characteristic analysis showed that LV end-systolic dimension ≥45 mm and hemoglobin level <13.4 g/dl were the best cut-off values for postoperative mortality. In conclusion, preoperative LV end-systolic dimension and hemoglobin level are independent prognostic factors of survival after aortic valve surgery in patients with chronic severe AR and normal LV EFs.

Survival in patients with severe aortic regurgitation and severe left ventricular dysfunction is improved by aortic valve replacement: results from a cohort of 166 patients with an ejection fraction < or =35%

BACKGROUND

Aortic valve replacement (AVR) in patients with severe aortic regurgitation (AR) and left ventricular (LV) dysfunction entails a higher surgical risk. Though it may improve symptoms and LV size, it is not known whether it translates into a survival benefit.

METHODS AND RESULTS

This retrospective cohort study included patients screened from our echocardiographic database between 1993 and 2007 for patients with severe AR and LV ejection fraction (EF) < or =35%. Charts reviews were conducted for clinical, pharmacological, and surgical information. Mortality data were obtained from the social security death index and analyzed as a function of AVR adjusted for the propensity score. Of the 785 patients with severe AR, 166 patients had severe LV dysfunction defined as an EF < or =35%: 69% of these were men, age 65+/-16 years, and LV EF was 23+/-8%. Kaplan-Meier analysis revealed that performance of AVR (n=53) was associated with a better survival (P=0.001). Adjusted for the propensity score, AVR was associated with a significantly lower mortality hazard (HR 0.59, CI 0.42 to 0.98, P=0.04).

CONCLUSIONS

There is a clear reluctance to offer AVR in a large number of patients with severe AR associated with LV dysfunction. However, the performance of AVR in these patients is associated with a mortality benefit supporting the current ACC/AHA guidelines.

Improved Outcomes After Aortic Valve Surgery for Chronic Aortic Regurgitation With Severe Left Ventricular Dysfunction

OBJECTIVES

Among patients undergoing aortic valve surgery for chronic aortic regurgitation (AR), we sought to: 1) compare survival among those with and without severe left ventricular dysfunction (LVD); 2) identify risk factors for death, including LVD and date of operation; and 3) estimate contemporary risk for cardiomyopathic patients.

BACKGROUND

Patients with chronic AR and severe LVD have been considered high risk for aortic valve surgery, with limited prognosis. Transplantation is considered for some.

METHODS

From 1972 to 1999, 724 patients underwent surgery for chronic AR; 88 (12%) had severe LVD. They were propensity matched to patients with nonsevere LVD to compare hospital mortality, interaction of operative date with severity of LVD, and late survival. Propensity score-adjusted multivariable analysis was performed for all 724 patients to identify risk factors for death.

RESULTS

Survival was lower (p = 0.04) among patients with severe LVD than among matched patients with nonsevere LVD (30-day, 1-, 5-, and 25-year survival estimates were 91% vs. 96%, 81% vs. 92%, 68% vs. 81%, and 5% vs. 12%, respectively). However, survival of patients with severe LVD improved dramatically across the study time frame (p = 0.0004): hospital mortality decreased from 50% in 1975 to 0% after 1985, and time-related survival in patients with severe LVD operated on since 1985 became equivalent to that of matched patients with nonsevere LVD (p = 0.96).

CONCLUSIONS

Neutralizing risk of severe LVD has improved early and late survival such that aortic valve surgery for chronic AR and cardiomyopathy is no longer a high-risk procedure for which transplantation is the best option.

Long-term survival and functional results after aortic valve replacement in asymptomatic patients with chronic severe aortic regurgitation and left ventricular dysfunction

OBJECTIVES

We examined the influence of medical treatment on the results of surgery in terms of long-term survival and functional results in patients with chronic, severe aortic regurgitation (AR).

BACKGROUND

Asymptomatic patients with AR and a reduced left ventricular ejection fraction (LVEF) are at high risk because of a higher-than-expected long-term mortality. The influence of preoperative medical therapy on the outcome after aortic valve replacement (AVR) is not well known.

METHODS

Surgery was indicated for the appearance of a reduced LVEF (<50%). At the time of AVR, there were 134 patients treated with nifedipine (group A), and 132 received no medication (group B).

RESULTS

Operative mortality was similar in the two groups (0.75% vs. 0.76%, p = NS). The LVEF normalized in all of group A, whereas it remained abnormal in 36 group B patients (28%). At 10-year follow-up, LVEF persisted higher in group A (62 +/- 5% vs. 48 +/- 4%, p < 0.001). Five-year survival was similar in the two groups (94 +/- 2% vs. 94 +/- 3%, p = NS). Group A showed a 10-year survival not different from expected and significantly higher than that in group B (85 +/- 4% vs. 78 +/- 5%, p < 0.001), which had a worse survival than expected.

CONCLUSIONS

Unloading treatment with nifedipine in AR allows one to indicate AVR at the appearance of a reduced LVEF with a low operative mortality and an optimal long-term outcome. The concept of surgical correction of AR indicated for reduced LVEF may not be applied to all patients. Indeed, in a large amount of untreated patients, a reduced LVEF preoperatively is not reversed by prompt surgery, indicating irreversible myocardial damage, and 10-year survival is worse than expected.

Automated quantification of left ventricular function by the automated contour tracking method

The automated contour tracking (ACT) method has been developed for the automated measurement of area volume using the energy minimization method without tracing a region of interest. The purpose of this study was to compare the ACT method and left ventriculography (LVG) for the measurement of left ventricular (LV) function in the clinical setting. An apical four-chamber view was visualized by two-dimensional echocardiography and recorded for off-line analysis in 14 patients with high-quality images who underwent LVG. The ACT method automatically traces the endocardial border from the recorded images and calculates LV volumes (end-diastole and end-systole) and ejection fraction (EF). Both ACT and LVG were compared by linear regression analysis for the measurement of EF. EF determined by the ACT method agreed well with that by LVG (r = 0.96, y = 0.94x + 4.6, standard error of the estimate = 3.9%). The mean difference between the ACT and LVG was -1.4%+/- 7.3%. In conclusion, the ACT method is reliable for noninvasive estimation of EF in high-quality images. This suggests that this new technique may be useful in the automated quantification of LV function.

Ten-year clinical laboratory follow-up after application of a symptom-based therapeutic strategy to patients with severe chronic aortic regurgitation of predominant rheumatic etiology

OBJECTIVES

This study was designed to assess the feasibility and the long-term results of a symptom-based strategy of aortic valve replacement in a Brazilian population with predominant rheumatic etiology.

BACKGROUND

Optimal criteria for valve replacement in aortic regurgitation (AR) are still not entirely clear. The appearance of symptoms is an indication for surgery, but may be associated with myocardial damage. Although cardiac imaging data have provided a safer guide for such decisions, the use of symptom-based surgical indication has not been validated and might conceivably be better in populations with predominant rheumatic etiology and younger age.

METHODS

Echocardiography and rest-exercise radionuclide ventriculography were performed in 75 patients with severe AR, age 28 +/- 9 years, over a period of 10 +/- 0.69 years. Thirty-seven patients developed symptoms and underwent aortic valve replacement surgery within six months. Thirty-eight patients remained asymptomatic and were managed medically.

RESULTS

Survival was 100% in asymptomatic patients and 82% in symptomatic. Surgical treatment caused marked ventricular remodeling, with ventricular diameter involution and an improvement of rest-exercise ejection fraction percent variation. Multivariate analysis showed that the probability of developing symptoms within 10 years was 58% for a patient with a left ventricular end-diastolic diameter > or =70 mm and 76% for a patient with left ventricular end-systolic (LVESD) > or =50 mm. Logistic regression identified LVESD and age as the most predictive and specific, but not sensitive, indicators of symptom development.

CONCLUSIONS

Application of a standardized therapeutic strategy to patients with severe AR and predominant rheumatic etiology resulted in 90.6% survival after 10 years of follow-up.