Survival and functional results after valve replacement for aortic regurgitation from 1976 to 1983: impact of preoperative left ventricular function

Left Ventricular Reverse Remodeling after Surgical Aortic Valve Replacement for Aortic Regurgitation-An Explorative Study

BACKGROUND

The timing of treatment for chronic aortic valve regurgitation (AR), especially in asymptomatic patients, is gaining attention since less invasive strategies have become available. The aim of the present study was to evaluate left ventricular reverse remodeling after aortic valve replacement (AVR) for severe AR.

METHODS

Patients (n = 25) who underwent surgical AVR for severe AR with left ventricular ejection fraction (LVEF) less than 55% were included in this study. Preprocedural and follow-up clinical and echocardiographic measurements of LVEF and left ventricular (LV) diameters were retrospectively analyzed.

RESULTS

Mean LVEF increased significantly following surgical AVR (p < 0.0001). LV diameters showed a clear regression (p = 0.0088). Younger patients and those receiving a mechanical valve tended to have less improved LVEF on follow-up than patients over 60 years or the ones who were implanted with a biological prosthesis (p = 0.0239 and p = 0.069, respectively). Gender had no effect on the degree of LVEF improvement (p = 0.4908).

CONCLUSIONS

We demonstrated significant LV reverse remodeling following AVR for AR. However, more data are needed on LV functional and geometrical improvement comparing the different types of valve prostheses to provide an optimal treatment strategy.

Economic Benefits of Surgical Aortic Valve Replacement on Patients With Symptomatic Aortic Valve Regurgitation

BACKGROUND

Aortic regurgitation is distinguished by the backflow of blood from the aorta into the left ventricle. American College of Cardiology/American Heart Association guidelines recommend surgical aortic valve replacement (SAVR) for patients with symptomatic aortic regurgitation (sAR). This study estimates the difference in mortality, health care use, and costs between patients with sAR who receive SAVR within 12 months of diagnosis versus those who do not.

METHODS AND RESULTS

We used the Optum United Healthcare database to identify 132 317 patients diagnosed with sAR from 2016 to 2021 who had at least 6 months of enrollment before sAR and 12 months of enrollment after. Criteria were no history of aortic stenosis or transcatheter aortic valve replacement and ≥2 visits for heart failure, angina, dyspnea, or syncope. Outcomes were all-cause mortality, health care use, and annualized cost. Baseline differences in demographics and comorbidities were adjusted with inverse propensity score weighting. We modeled survival and estimated health care use and costs using Cox proportional hazards and general linear models, respectively. Of the 132 317 patients, 400 underwent SAVR within 12 months of diagnosis. They were on average younger, more often men, and with a slightly higher Elixhauser Comorbidity Index score. After inverse propensity score weighting, patients with sAR who had SAVR had lower mortality, fewer inpatient and emergency department visits, fewer hospital days, and lower annualized cost.

CONCLUSIONS

SAVR performed within 12 months of an sAR diagnosis is associated with improved mortality and lower annualized health care use and costs. These clinical and economic benefits should be considered when managing patients with sAR.

Left ventricular ejection fraction: clinical, pathophysiological, and technical limitations

Risk stratification of cardiovascular death and treatment strategies in patients with heart failure (HF), the optimal timing for valve replacement, and the selection of patients for implantable cardioverter defibrillators are based on an echocardiographic calculation of left ventricular ejection fraction (LVEF) in most guidelines. As a marker of systolic function, LVEF has important limitations being affected by loading conditions and cavity geometry, as well as image quality, thus impacting inter- and intra-observer measurement variability. LVEF is a product of shortening of the three components of myocardial fibres: longitudinal, circumferential, and oblique. It is therefore a marker of global ejection performance based on cavity volume changes, rather than directly reflecting myocardial contractile function, hence may be normal even when myofibril's systolic function is impaired. Sub-endocardial longitudinal fibers are the most sensitive layers to ischemia, so when dysfunctional, the circumferential fibers may compensate for it and maintain the overall LVEF. Likewise, in patients with HF, LVEF is used to stratify subgroups, an approach that has prognostic implications but without a direct relationship. HF is a dynamic disease that may worsen or improve over time according to the underlying pathology. Such dynamicity impacts LVEF and its use to guide treatment. The same applies to changes in LVEF following interventional procedures. In this review, we analyze the clinical, pathophysiological, and technical limitations of LVEF across a wide range of cardiovascular pathologies.

Aortic Regurgitation and Heart Failure: Advances in Diagnosis, Management, and Interventions

This review discusses the contemporary clinical evaluation and management of patients with comorbid aortic regurgitation (AR) and heart failure (HF) (AR-HF). Importantly, as clinical HF exists along the spectrum of AR severity, the present review also details novel strategies to detect early signs of HF before the clinical syndrome ensues. Indeed, there may be a vulnerable cohort of AR patients who benefit from early detection and management of HF. Additionally, while the mainstay of operative management for AR has historically been surgical aortic valve replacement, this review discusses alternate procedures that may be beneficial in high-risk cohorts.

Machine learning-based risk stratification for mortality in patients with severe aortic regurgitation

Aims

The current guidelines recommend aortic valve intervention in patients with severe aortic regurgitation (AR) with the onset of symptoms, left ventricular enlargement, or systolic dysfunction. Recent studies have suggested that we might be missing the window of early intervention in a significant number of patients by following the guidelines.

Methods and results

The overarching goal was to determine if machine learning (ML)-based algorithms could be trained to identify patients at risk for death from AR independent of aortic valve replacement (AVR). Models were trained with five-fold cross-validation on a dataset of 1035 patients, and performance was reported on an independent dataset of 207 patients. Optimal predictive performance was observed with a conditional random survival forest model. A subset of 19/41 variables was selected for inclusion in the final model. Variable selection was performed with 10-fold cross-validation using random survival forest model. The top variables included were age, body surface area, body mass index, diastolic blood pressure, New York Heart Association class, AVR, comorbidities, ejection fraction, end-diastolic volume, and end-systolic dimension, and the relative variable importance averaged across five splits of cross-validation in each repeat were evaluated. The concordance index for predicting survival of the best-performing model was 0.84 at 1 year, 0.86 at 2 years, and 0.87 overall, respectively.

Conclusion

Using common echocardiographic parameters and patient characteristics, we successfully trained multiple ML models to predict survival in patients with severe AR. This technique could be applied to identify high-risk patients who would benefit from early intervention, thereby improving patient outcomes.

Additional Prognostic Value of Tissue Doppler Evaluation in Patients with Aortic Stenosis and Left-Ventricular Systolic Dysfunction Undergoing Aortic Valve Replacement

Background and Objectives: Patients with surgical aortic stenosis (AS) show impaired diastolic filling, which is a risk factor for early and late mortality after aortic valve replacement (AVR). There is a paucity of information concerning the impact of restrictive diastolic filling and the evolution of diastolic dysfunction in the early and medium terms post-AVR. We aimed to determine the prognostic value of the presence of a restrictive left-ventricular (LV) diastolic filling pattern (LVDFP) and dilated left atrium (LA) in patients with AS and LV systolic dysfunction (LVEF < 40%) who underwent AVR, and to define the independent predictors for immediate and long-term prognosis and their value for preoperative risk estimation. Materials and Methods: The study was prospective and included 197 patients with surgical AS and LVEF <40% who underwent AVR. Preoperative echocardiographic examinations were repeated at day 10, at 1, 3 and 6 months, and at 1 and 2 years after surgery, with evaluation of LVEF, diastolic function and LA dimension index (mm/m2). Depending on LV systolic performance, patients were classified as Group A (LVEF: 30−40%) or Group B (LVEF < 30%). Results: The main echographic independent parameters for early and late postoperative death were: restrictive LVDFP, significant pulmonary hypertension, LV end-systolic diameter (LVESD) >55 mm and the presence of second-degree mitral regurgitation. Restrictive LVDFP and LA dimension >30 mm/m2 were independent predictors for fatal outcome (p = 0.0017). Conclusions: Assessment of diastolic function and LA dimension are reliable parameters in predicting fatal outcome and hospitalization for heart failure, having an independent and incremental prognostic value in patients with surgical AS. Complete evaluation of LVDFP with all the echographic measurements (including TDI) should routinely be part of the preoperative assessment of patients with LV systolic dysfunction undergoing AVR.

Predictors of heart failure and all-cause mortality in asymptomatic patients with moderate and severe aortic regurgitation

BACKGROUND

Class I indications for aortic valve replacement (AVR) for severe chronic aortic regurgitation (AR) include AR attributable symptoms or left ventricular (LV) ejection fraction <50%. As noninvasive estimates of elevated LV filling pressures (LVFP's) have been noted to predict heart failure (HF) readmission and all-cause mortality (ACM) in HF patients, we hypothesize that elevated LVFP's may also be independent predictors of HF and ACM in chronic AR.

METHODS

We developed a single center patient database of moderate or greater AR diagnoses between 2003 and 2008 and followed each patient through January 2013. We included patients with >30 days follow-up with interpretable Doppler-echocardiograms. We recorded demographic variables, EuroScore II, incident HF and ACM, and Doppler-echo variables of LV size, systolic and diastolic function.

RESULTS

Patients with severe AR (105 patients) and moderate AR (201 patients) had similar EuroScore II values and similar incident HF and ACM. For the 180 patients who developed HF, effective arterial elastance (aHR = 1.70 (1.01-2.83), p = .041), LV end-diastolic dimension (aHR = 1.83, (1.11-3.03), p = .0176), E/e' (aHR = 3.04, (1.83-5.05), p < .0001), eccentric hypertrophy (EH) (aHR = 2.39, (1.62-5.12), p = .0004), and tricuspid regurgitation (TR) velocity (aHR = 5.75, (3.70-10.36), p < .0001) were independent predictors. For the 118 patients with ACM, EH (aHR = 1.73, (1.02-3.28), p = .0414), systolic blood pressure (aHR = .58, (.33-.95), p = .0301), left atrial volume index (aHR = 1.82, (1.06-3.06), p = .0293), E/e' (aHR = 1.83, (1.07-3.08), p = .0280), and TR velocity (aHR = 4.14, (2.22-6.49), p < .0001) were independent predictors.

CONCLUSIONS

Elevated TR velocity and EH were strong markers of HF and ACM in patients with asymptomatic severe AR and in moderate AR.

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.

Early Identification of Decompensated Aortic Regurgitation With Stress Echocardiography

•Chronic severe AR progresses slowly with a long asymptomatic compensated phase.•Stress echocardiography (SE) has the ability to uncover subclinical LV dysfunction.•SE can identify patients with severe AR who may benefit from earlier intervention.

Optimizing Timing of Valve Intervention in Patients With Asymptomatic Severe Valvular Heart Disease

The management of valvular heart disease has changed dramatically over the past decade with advances in cardiac imaging, the use of novel biomarkers, and the development of transcatheter valve repair and replacement technology. International society guidelines have kept pace to provide recommendations for diagnosis, follow-up, and timing of intervention. The most challenging patient cohort for clinicians are patients with asymptomatic severe disease in whom the optimal timing of intervention can be ill-defined. It is a fine balance between the risks of early intervention on asymptomatic patients and improving patient outcomes by preventing long-term cardiac complications. The key in optimal patient management is gathering the necessary information on patient risk and combining that with the risk, efficacy, and durability of valve interventions to arrive at the appropriate timing for intervention. This group of patients will be the focus of this review as we delve into the natural history, recommended follow-up, and indications for intervention in patients with degenerative aortic and mitral valve disease.

Prognostic implications of left atrial dilation in aortic regurgitation due to bicuspid aortic valve

OBJECTIVE

To investigate the prognostic value of left atrial volume index (LAVI) in patients with moderate to severe aortic regurgitation (AR) and bicuspid aortic valve (BAV).

METHODS

554 individuals (45 (IQR 33-57) years, 80% male) with BAV and moderate or severe AR were selected from an international, multicentre registry. The association between LAVI and the combined endpoint of all-cause mortality or aortic valve surgery was investigated with Cox proportional hazard regression analyses.

RESULTS

Dilated LAVI was observed in 181 (32.7%) patients. The mean indexed aortic annulus, sinus of Valsalva, sinotubular junction and ascending aorta diameters were 13.0±2.0 mm/m², 19.4±3.7 mm/m², 16.5±3.8 mm/m² and 20.4±4.5 mm/m², respectively. After a median follow-up of 23 (4-82) months, 272 patients underwent aortic valve surgery (89%) or died (11%). When compared with patients with normal LAVI (<35 mL/m²), those with a dilated LAVI (≥35 mL/m²) had significantly higher rates of aortic valve surgery or mortality (43% and 60% vs 23% and 36%, at 1 and 5 years of follow-up, respectively, p<0.001). Dilated LAVI was independently associated with reduced event-free survival (HR=1.450, 95% CI 1.085 to 1.938, p=0.012) after adjustment for LV ejection fraction, aortic root diameter, LV end-diastolic diameter and LV end-systolic diameter.

CONCLUSIONS

In this large, multicentre registry of patients with BAV and moderate to severe AR, left atrial dilation was independently associated with reduced event-free survival. The role of this parameter for the risk stratification of individuals with significant AR merits further investigation.

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.

Prevalence and relevance of impaired left ventricular function in chronic moderate regurgitation of native aortic valves

Background: Reduced ejection fraction (EF) in chronic moderate aortic regurgitation (AR) could be either due to a late remodelling response after longstanding moderate AR, or could represent a specific phenotype of cardiomyopathy (CMP) with concomitant AR. The aim of this study was to analyse progression of left ventricular (LV) impairment in moderate AR. Methods: All patients in our echocardiography database between 2005 and 2016 were screened to identify pure chronic moderate AR, excluding significant coronary artery disease (CAD) or concomitant valve disease. Remaining 152 patients were divided into three groups: (a) preserved systolic LV function; (b) reduced LV EF and prediagnosed concomitant cardiomyopathy (CMP); (c) reduced LV EF without prediagnosed CMP. Results: The majority patients (group A = 66%) had preserved systolic LV function, remaining oligosymptomatic with stable LVEDD at follow-up. Non-CMP patients with reduced EF at baseline (group C = 18%) were significantly older (group C: 74 vs. group A: 61 years, p < .001) whereas left ventricular end-diastolic diameter (LVEDD) significantly increased over time (p = .046). Development of renal insufficiency, atrial fibrillation and NYHA > II were significant risk factors linked to the worsening of LV function in patients with moderate AR. Conclusion: Preserved LV EF and LVEDD remain stable over a long lasting period in the majority of patients. However, these data suggest that some patients develop reduced LV EF, even without progression of AR to severe, especially if renal insufficiency or atrial fibrillation are present.

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.

Cardiac Mechanics in Isolated Bicuspid Aortic Valve Disease With Normal Ejection Fraction: A Study of Various Valvular Lesion Types

Aortic stenosis (AS) and aortic regurgitation (AR) are associated with congenital isolated bicuspid aortic valve (BAV) disease. The chronic pressure overload of AS and the volume overload of AR are known to impair the left ventricular function. This study assessed whether two-dimensional speckle tracking echocardiography (2D-STE) is capable of detecting the myocardial dysfunction associated with BAV caused by various aortic valve lesions in patients retaining normal ejection fraction (EF).Thirty-two isolated BAV patients and 20 healthy tricuspid aortic valve (TAV) volunteers were recruited. BAV patients were divided into 4 subgroups based on aortic valvular lesion types: normal function (NF) group, isolated AS group, isolated AR group, and a group who had both AS&AR. Myocardial strain and degree of twist were analyzed and compared between the BAV and TAV groups, as well as between valvular lesion groups and the NF group.Compared with healthy TAV controls, global radial strain (GRS), global circumferential strain (GCS), global longitudinal strain (GLS), and twist angle absolute values were lower in the BAV group (P < 0.05). The AS, AR, and AS&AR groups all demonstrated a significant decrease in GRS and GCS when compared with the TAV group. The AS and AS&AR groups demonstrated lower GLS than the TAV group, and the smallest degree of twist was detected in the AR group. There were no significant differences between the NF and TAV groups. The AR and AS&AR groups demonstrated significant differences in multiple parameters of cardiac mechanics compared with the NF group.2D-STE is able to detect altered cardiac mechanics associated with aortic lesion types in BAV patients with normal EF compared with normal TAV controls, and so can provide valuable information for clinical decision-making.

Sildenafil treatment attenuates ventricular remodeling in an experimental model of aortic regurgitation

BACKGROUND

Currently there is no reliable medical treatment for aortic regurgitation (AR).

METHODS

Thirty-nine Sprague-Dawley rats underwent creation of AR or sham operation. Treated rats were assigned to early or late institution of sildenafil therapy (100 mg/kg/day) for a total of 10 weeks. Treatment-effects were measured by serial echocardiography, invasive hemodynamic measurements, and tissue analysis.

RESULTS

Rats assigned to early treatment developed less remodeling than untreated rats. Thus, left ventricular (LV) dilation was blunted by sildenafil with end-systolic diameter being significantly smaller (6.6 ± 0.4 vs. 7.7 ± 0.4 mm, respectively, p < 0.05). Also, LV wall thickness was significantly decreased in treated rats compared to controls (2.23 ± 0.08 vs. 2.16 ± 0.05 mm, p < 0.01). Fractional shortening was improved by treatment (p < 0.05). Myocardial fibrosis was borderline decreased by treatment (p = 0.09). Akt was increased in treated compared to controls (p < 0.05).

CONCLUSION

Sildenafil slightly inhibits LV remodeling and improves fractional shortening in rats with AR when treatment is initiated early.

The management of patients with aortic regurgitation and severe left ventricular dysfunction: a systematic review

A systematic search of Medline, EMBASE and CINAHL electronic databases was performed. Original research articles reporting all-cause mortality following surgery in patients with aortic regurgitation and severe left ventricular systolic dysfunction (LVSD) were identified. Nine of the 10 eligible studies were observational, single-center, retrospective analyses. Survival ranged from 86 to 100% at 30 days; 81 to 100% at 1 year and 68 to 84% at 5 years. Three studies described an improvement in mean left ventricular ejection fraction (LVEF) following aortic valve replacement (AVR) of 5-14%; a fourth study reported an increase in mean left ventricular ejection fraction (LVEF) of 9% in patients undergoing isolated AVR but not when AVR was combined with coronary artery bypass graft and/or mitral valve surgery. Three studies demonstrated improvements in functional New York Heart Association (NYHA) class following AVR. Additional studies are needed to clarify the benefits of AVR in patients with more extreme degrees of left ventricular systolic dysfunction (LVSD) and the potential roles of cardiac transplantation and transaortic valve implantation.

Detection of subtle left ventricular systolic dysfunction in patients with significant aortic regurgitation and preserved left ventricular ejection fraction: speckle tracking echocardiographic analysis

AIMS

The aim of this study was to characterize left ventricular (LV) mechanics in symptomatic and asymptomatic patients with moderate-to-severe or severe aortic regurgitation (AR) and preserved ejection fraction (left ventricular ejection fraction) using two-dimensional speckle tracking echocardiography (2D-STE). The association between baseline LV strain and development of indications for surgery in asymptomatic patients was also evaluated.

METHODS AND RESULTS

A total of 129 patients with moderate-to-severe or severe AR and LVEF >50% (age 55 ± 17 years, 64% male, 53% asymptomatic at baseline) were included. Standard echocardiography and 2D-STE were performed at baseline. Compared with asymptomatic patients, symptomatic patients had significantly impaired LV longitudinal (-14.9 ± 3.0 vs. -16.8 ± 2.5%, P < 0.001), circumferential (-17.5 ± 2.9 vs. -19.3 ± 2.8%, P = 0.001), and radial (35.7 ± 12.2 vs. 43.1 ± 14.7%, P = 0.004) strains. Among 49 asymptomatic patients who were followed up, 26 developed indications for surgery (symptoms onset or LVEF ≤50%). These patients had comparable LV volumes, LVEF, and colour Doppler assessments of AR jet at baseline, but more impaired LV longitudinal (P = 0.009) and circumferential (P = 0.017) strains compared with patients who remained asymptomatic. Impaired baseline LV longitudinal (per 1% decrease, HR = 1.21, P = 0.04) or circumferential (per 1% decrease, HR = 1.22, P = 0.04) strain was independently associated with the need for surgery.

CONCLUSION

Multidirectional LV strain was more impaired in symptomatic than in asymptomatic patients with moderate-to-severe or severe AR, despite preserved LVEF. In asymptomatic AR patients, longitudinal and circumferential strains identified patients who would require surgery during follow-up.

Echocardiographic predictors of early postsurgical myocardial dysfunction in pediatric patients with aortic valve insufficiency

In chronic aortic insufficiency (AI), left-ventricular (LV) dysfunction must be detected early to allow timely surgery. Strain and strain rate have been used for this purpose in adults, but the value of this method in pediatric AI has not been established. Forty patients with moderate to severe AI were included in this retrospective study. LV function was assessed by strain analysis and conventional echocardiography both before and after surgery. Of the 32 patients with preserved preoperative ejection fraction (EF; >50 %), 8 had postoperative dysfunction (<50 %). Mean conventional indices of global LV systolic performance for the entire cohort of patients with AI were predominantly in the normal range before surgery. Preoperative values for LV global longitudinal strain (GLS) and strain rate (GLSr) were normal. After surgery, there was a significant decrease in shortening and EF. There was a significant decrease from preoperative to postoperative values for both GLS (-16.07 ± 3.82 vs. -11.06 ± 3.88; p < 0.0001) and GLSr (-0.89 ± 0.24 vs. -0.72 ± 0.27; p = 0.0021). A preoperative GLS of -15.3 (AUC = 0.83, CI = 0.69-0.98, p < 0.0001) and a GLSr of -0.79/s (AUC = 0.86, CI = 0.73-0.98, p < 0.0001) were determined to be predictors of early postoperative dysfunction after surgical repair of moderate to severe AI. A preoperative GLS value of ≤-15.3 and GLSr value of -0.79/s or less are predictors of postoperative ventricular dysfunction, which is defined by EF <50 %. GLS and GLSr value determination may be useful as part of the echocardiographic assessment AI and may help determine the optimal timing of surgery in pediatric patient with at least moderate AI.

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.

MRI-based multiparametric strain analysis predicts contractile recovery after aortic valve replacement for aortic insufficiency

BACKGROUND

Guidelines for referral of chronic aortic insufficiency (AI) patients for aortic valve replacement (AVR) suggest that surgery can be delayed until symptoms or reduction in left ventricular (LV) contractile function occur. The frequent occurrence of reduced LV contractile function after AVR for chronic AI suggests that new contractile metrics for surgical referral are needed.

METHODS

In 16 chronic AI patients, cardiac MRI tagged images were analyzed before and 21.5 ± 13.8 months after AVR to calculate LV systolic strain. Average measurements of three strain parameters were obtained for each of 72 LV regions, normalized using a normal human strain database (n = 63), and combined into a composite index (multiparametric strain z score [MSZ]) representing standard deviation from the normal regional average.

RESULTS

Preoperative global MSZ (72-region average) correlated with post-AVR global MSZ (R(2) = 0.825, p < 0.001). Preoperative global MSZ also predicts improvement of impaired regions (N = 271 regions from 14 AI patients, R(2) = 0.392, p < 0.001). Preoperative MRI-based LV ejection fraction (LVEF) is also predictive (r = 0.410, p < 0.001). Although global preoperative MSZ had a significantly higher correlation than preoperative LVEF with improvement of injured regions (p < 0.001), both measures convey the same phenomenon.

CONCLUSIONS

Global preoperative MRI-based multiparametric strain predicts global strain postoperatively, as well as improvement of regions (n = 72 per LV) with impaired contractile function. Global contractile function is an important correlate with improvement in regionally impaired contractile function, perhaps reflecting total AI volume-overload burden (severity/duration of AI).

Heterogeneous distribution of left ventricular contractile injury in chronic aortic insufficiency

BACKGROUND

Global systolic strain has been described previously in patients with chronic aortic insufficiency (AI). This study explored regional differences in contractile injury.

METHODS

Tagged magnetic resonance images of the left ventricle (LV) were acquired and analyzed to calculate systolic strain in 42 patients with chronic AI. Multiparametric systolic strain analysis was applied to relate cardiac function in AI patients to a normal strain database (N = 60). AI patients were classified as having normal or poor function based on their results. A two-way repeated-measures analysis of variance was applied to analyze regional differences in injury.

RESULTS

The mean and standard deviation of raw strain values (circumferential strain, longitudinal strain, and minimum principal strain angle) are presented over the entire LV in our normal strain database. Of the 42 patients with AI, 15 could be defined as having poor function by multiparametric systolic strain analysis. In AI patients with poor function, statistical analysis showed significant differences in injury between standard LV regions (F(3.69,44.33) = 3.47, p = 0.017) and levels (F(1.49,17.88) = 4.41, p = 0.037) of the LV, whereas no significant differences were seen in the group with normal cardiac function.

CONCLUSIONS

Patients with poor function, as defined by multiparametric systolic strain z scores, exhibit a consistent, heterogeneous pattern of contractile injury in which the septum and posterior regions at the base are most injured.

Baseline diastolic dysfunction as a predictive factor of trastuzumab-mediated cardiotoxicity after adjuvant anthracycline therapy in breast cancer

To evaluate the interest in assessing left ventricular diastolic function at baseline for prediction of trastuzumab-mediated cardiotoxicity (TMC) in the setting of adjuvant treatment for breast cancer. The study included 118 women presenting with HER2-positive early-stage invasive breast cancer. Patients received trastuzumab therapy over 1 year, concurrent with six cycles of docetaxel (n = 53), or following anthracycline-based chemotherapy with a cumulative dose of 300 mg/m(2) (n = 45) or 600 mg/m(2) (n = 20) of epirubicine. RNA was performed before anthracycline-based chemotherapy, before trastuzumab treatment (baseline), and every 3 months during treatment. Left ventricular ejection fraction (LVEF) and peak ejection rate (PER) were calculated to evaluate LV systolic function; peak filling rate (PFR), and time to peak filling rate (TPFR) were also calculated to evaluate LV diastolic function. Eighteen patients (15%) developed grade 1 or 2 TMC during follow-up. No significant difference was observed for age, cardiovascular risk factors, fasting blood glucose level, heart rate, systolic blood pressure, baseline LVEF, PER, and PFR between patients with and without TMC. In contrast, patients with TMC showed a longer TPFR at baseline (median [Q1-Q3]: 165 ms [149-190] vs. 142 ms [130-162]; P < 0.001). Furthermore, by logistic regression analysis, baseline TPFR >180 ms and the cumulative dose of epirubicin remained independent predictors of TMC. Patients receiving 600 mg/m(2) of epirubicin before trastuzumab showed a higher incidence of TMC (35%) than did both patients who previously received 300 mg/m(2) of epirubicin (13%) and those who received only docetaxel associated with trastuzumab (9%). Impaired left ventricular diastolic function before treatment is an independent predictor of trastuzumab-mediated cardiotoxicity. The evaluation of diastolic function could allow optimal risk stratification before the introduction of trastuzumab.

CME: long-term outcome in asymptomatic patients with severe aortic regurgitation, normal left ventricular ejection fraction, and severe left ventricular dilatation

BACKGROUND

Although the guidelines consider severe left ventricular (LV) dilatation a class IIaC indication for surgery in asymptomatic patients with severe aortic regurgitation (AR) and normal LV function, the optimal management remains controversial. We aimed to assess the LV enlargement, hypertrophy and function, and the outcomes in these patients by the presence of severe LV dilatation at baseline.

METHODS

From our 20-year database, we identified all asymptomatic patients with severe AR and LV ejection fraction (EF) >50% and ≥2 echocardiograms ≥1 year apart. LV end-diastolic diameter >70 mm or LV end-systolic diameter >50 mm or LV end-systolic diameter index >25 mm/m(2) defined severe LV dilatation. A composite end point included onset of symptoms or LV dysfunction.

RESULTS

Eighty-four patients (52 ± 18 years, 61 men) were enrolled and followed-up for 7.1 ± 5.1 years. Two groups were defined: 22 patients with and 62 patients without severe LV dilatation at baseline. The progression of LV dilatation and hypertrophy, and the LVEF at last exam were similar in both groups. Twelve of 22 and 34 of 62 patients (P = 0.59) reached the end point. Vasodilators did not modify the progression of LV enlargement/hypertrophy. Ten of 22 and 25 of 62 patients (P = 0.45) underwent surgery and had similar postoperative LV diameters, mass, EF.

CONCLUSIONS

The progression of LV enlargement/hypertrophy and outcomes in asymptomatic patients with severe AR, normal LV function, and severe LV dilatation or the postoperative LV parameters were not influenced by the severe LV dilatation, suggesting that a close follow-up could delay surgery in this population.

Diastolic function predicts outcome after aortic valve replacement in patients with chronic severe aortic regurgitation

BACKGROUND

Due to eccentric hypertrophy and fibrosis, patients with severe aortic regurgitation (AR) have diastolic dysfunction. Increased fibrosis correlates with increased myocardial stiffness and worsening of diastolic function. Patients with irreversible left ventricular (LV) dysfunction have severe myocardial fibrosis and myocyte apoptosis and do not benefit from aortic valve replacement (AVR).

HYPOTHESIS

To investigate whether diastolic properties of LV predicts outcome after AVR in patients with chronic severe AR and LV systolic dysfunction.

METHODS

The study population consisted of 41 patients with chronic severe AR and LV systolic dysfunction. Preoperative echocardiographic examinations were repeated at the postoperative 6th month. Left ventricular ejection fraction (LVEF) was calculated. Diastolic function was evaluated with Doppler echocardiography. Patients were classified as Group 1 (impaired relaxation), Group 2 (pseudonormalization), and Group 3 (restrictive pattern).

RESULTS

Postoperative LVEF was significantly increased in Group 1, whereas it tended to decrease in Group 3. Left ventricular size was significantly decreased in Group 1 and 2 during the postoperative period. Multivariate linear regression analysis showed that deceleration time and early/late ratio were independent predictors of postoperative changes in LVEF.

CONCLUSIONS

Assessment of diastolic function is a reliable parameter in predicting outcome of AVR in patients with chronic AR and systolic dysfunction.

Valvular regurgitation and stenosis: when is surgery required?

Valvular heart disease is a growing public health problem, with an increasing prevalence due to an ageing population. Despite advances, the medical management of symptomatic valvular heart diseases remains suboptimal, necessitating surgical correction. The challenge remains in identifying an asymptomatic or mildly symptomatic patient who will benefit from timely surgery before irreversible changes in cardiac function have occurred. The potential risks of surgery versus watchful expectancy require careful decision-making. This review is a focused update on the existing guidelines and identifies the knowledge gaps and avenues of future research in the management of patients with valvular heart diseases.

Valve Pathology in Heart Failure: Which Valves Can Be Fixed?

Heart transplantation has evolved to become the gold standard treatment for patients who have symptoms of severe congestive heart failure associated with end-stage heart disease. From an epidemiologic perspective, this treatment is "trivial" because less than 2800 patients in the United States are offered transplantation because of limitations of age, comorbid conditions, and donor availability. New surgical strategies to manage patients who have severe end-stage heart disease have therefore evolved to cope with the donor shortage in heart transplantation and have included high-risk coronary artery revascularization, cardiomyoplasty, and high-risk valvular repair or replacement.