Aortic valve surgery in patients with left ventricular dysfunction

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.

Prognostic Markers and Long-Term Outcomes After Aortic Valve Replacement in Patients With Chronic Aortic Regurgitation

Background

The objectives of the present study were (1) to evaluate the echocardiographic prognostic factors associated with improved left ventricular (LV) systolic function after aortic valve replacement, and (2) to compare the long‐term outcomes after aortic valve replacement in chronic aortic regurgitation (AR) patients with or without LV dysfunction.

Methods and Results

A total of 280 patients who underwent aortic valve replacement because of chronic aortic regurgitation were studied. Patients with reduced LV systolic function (LV ejection fraction [LVEF] <50%; group reduced LVEF [rEF]; N=80) were compared with those with preserved LV systolic function (LVEF ≥50%; group preserved LVEF; N=200). Postoperative clinical outcomes, overall survival, and freedom from cardiac death were compared. Postoperative echocardiographic examinations were reviewed, and changes in echocardiographic parameters were analyzed. The parameters related to LVEF improvement or normalization were evaluated, and risk factors affecting long‐term survival were identified. Follow‐up was complete in 100% of patients, with a median follow‐up of 104.8 months. Overall and cardiac mortality‐free survival rates at postoperative 10 years were 80.1% and 92.9% and 87.3% and 97.2% in groups rEF and preserved LVEF, respectively (P=0.036 and P=0.058, respectively). LVEF tended to decrease in the early postoperative period but improved thereafter in both groups. Preoperative early diastolic transmitral flow velocity/mitral annular tissue velocity ratio was a parameter of postoperative improvement or normalization of LVEF in all patients (area under the curve, 0.719; P=0.003) and in group rEF patients (area under the curve, 0.726; P=0.011) with a cutoff value of 12.73. Preoperative early diastolic transmitral flow velocity/mitral annular tissue velocity ratio also was the parameter of overall survival in all patients (hazard ratio [HR], 1.08; P=0.001) and in group rEF patients (HR, 1.08; P=0.005).

Conclusions

Long‐term outcomes and survival after aortic valve replacement were related to preoperative LV function in patients with chronic aortic regurgitation. Preoperative early diastolic transmitral flow velocity/mitral annular tissue velocity ratio was correlated with the postoperative improvement or normalization of LVEF and long‐term survival, especially in group rEF patients.

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.

Impact of stroke volume on severe aortic stenosis in patients with normal left ventricular function

BACKGROUND

Low-flow (LF) aortic stenosis (AS) with a normal ejection fraction reportedly has a worse prognosis than normal-flow (NF) AS. We assessed whether the stroke volume affects early- and long-term survival of patients with AS undergoing aortic valve replacement.

METHODS AND RESULTS

From 2007 to 2016, 179 patients with AS and a normal ejection fraction (≥ 50%) and without other valve diseases were divided into two groups according to the stroke volume index (SVI): NF group (SVI ≥ 35 ml/m², n = 167) and LF group (SVI < 35 ml/m², n = 12). Early- and long-term survival was compared between the two groups. Preoperative echocardiography showed that the end-diastolic diameter and aortic valve area were smaller in the LF than NF group (43 ± 1.9 vs. 48 ± 0.4 mm, p < 0.005 and 0.33 ± 0.14 vs. 0.49 ± 0.14 cm²/m², p < 0.0005, respectively). Hospital mortality was significantly higher (16.7% vs. 1.8%, p < 0.05) and 5-year overall survival was lower (58 ± 17 vs. 84 ± 4.2 months, p < 0.005) in the LF than NF group.

CONCLUSION

Patients with LF AS had worse operative and long-term outcomes than those with NF, even though they had preserved LV function.

[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.

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.

High-risk aortic valve replacement: are the outcomes as bad as predicted?

BACKGROUND

Percutaneous aortic valve replacement (PAVR) trials are ongoing in patients with an elevated European System for Cardiac Operative Risk Evaluation (EuroSCOREs), patients believed to have high mortality rates and poor long-term prognoses with valve replacement surgery. It is, however, uncertain that the EuroSCORE model is well calibrated for such high-risk AVR patients. We evaluated EuroSCORE prediction vs a single institution's surgical results in this target population.

METHODS

From January 1996 through March 2006, 731 patients with EuroSCOREs of 7 or higher underwent isolated AVR. In this cohort, 313 (42.8%) were septuagenarians, 322 (44.0%) were octogenarians or nonagenarians, 233 (31.9%) had had previous cardiac procedures, 237 (32.4%) had atheromatous aortas, and 127 (17.4%) had cerebrovascular disease. A minimally invasive approach was used in 469 (64.2%). Data collection was prospective. Long-term survival was computed from the Social Security Death Benefit Index.

RESULTS

The mean EuroSCORE was 9.7 (median, 10), and the mean logistic EuroSCORE was 17.2%. Actual hospital mortality was 7.8% (57 of 731). Multivariate analysis showed ejection fraction of less than 0.30 (p = 0.002; odds ratio [OR], 3.13), chronic obstructive pulmonary disease (p = 0.019; OR, 2.14), and peripheral vascular disease (p = 0.048; OR, 2.13) were significant predictors of hospital mortality. Complication(s) occurred in 73 patients (9.9%). Freedom from all-cause death (including hospital mortality) was 72.4% at 5 years (n = 152). Age (p < 0.001), previous cardiac operations (p < 0.014; OR, 1.51), renal failure (p < 0.002; OR, 2.37), and chronic obstructive pulmonary disease (p < 0.007; OR, 1.30) were predictors of worse survival.

CONCLUSIONS

Logistic EuroSCORE greatly overpredicts mortality in these patients. Five-year survival is good, unlike suggestions from earlier EuroSCORE analyses. This raises concern about unknown long-term percutaneous prosthesis function. Clinical trials for these patients must include randomized surgical controls and have long-term end points.

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.

Nontransplant surgical options for congestive heart failure

Although advanced heart failure has been considered the main indication for heart transplantation, the increasing number of candidates and shortage of organs for transplantation, with accumulating waiting lists, has originated another look into more conventional surgery, previously considered of prohibitive risk. In fact, many cases are a result of anatomic lesions that can be corrected by conventional surgery, and in the past decade many surgical groups have obtained good and even excellent results in the treatment of aortic stenosis with low output, and in aortic and mitral regurgitation with severe left ventricular (LV) dysfunction. Also, ischemic and idiopathic dilated cardiomyopathy have been successfully treated by several types of LV remodeling surgery, with or without coronary grafting. Many of these procedures achieved excellent operative, medium-, and long-term results and survival, which match well those observed with cardiac transplantation, most often with advantages in the quality of life and, not unimportantly, in financial costs. For operated patients, especially those with ischemic cardiomyopathy, close follow-up for cardiac failure is extremely important in order to detect the right moment for heart transplantation, if it becomes necessary.

Pulmonary autografts in patients with severe left ventricular dysfunction

BACKGROUND

Performing a Ross operation in patients with severe left ventricular dysfunction is controversial. The objective in this retrospective study was to determine the outcome of 15 patients with aortic valve disease (11 had aortic insufficiency and 4 had aortic insufficiency and aortic stenosis) associated with reduced left ventricular function (ejection fraction < 40%) treated with a pulmonary autograft.

METHODS

We identified 15 patients with severe left ventricular dysfunction from 226 consecutive pulmonary autograft procedures done between age 18 and 50 years from 1986 to 2001. Patients had documented preoperative ejection fraction less than 40% and were in New York Heart Association class III or IV. Preoperative ejection fraction ranged from 18% to 37% (mean, 31% +/- 6.5%). Transthoracic echocardiograms obtained preoperatively and at 1-week, 6-month, and 1- and 2-year intervals were reviewed. Records were evaluated for survival, clinical status, left ventricular function, and valve function.

RESULTS

There were no operative deaths, late deaths, or reoperations. All patients had follow-up examinations within the past year and are clinically well (67% > 2 years follow-up). Ten of 15 patients (67%) had substantially improved ventricular function (> 20% increase). The average ejection fraction increased from 31% +/- 7% preoperatively to 51% +/- 11% at 2 years, and the increase is significant from 1 week on (p < 0.02). Average left ventricular mass index decreased by 41% at 6 months (n = 10; p = 0.009) and by 44% at 2 years (n = 9; p = 0.02). Mean Z values for left ventricular mass decreased from 7.6 to 3.6 after more than 2 years (p = 0.007).

CONCLUSIONS

The Ross operation is an appropriate option in adults age 50 or younger in the presence of decreased left ventricular ejection fraction. Neither operative mortality nor postoperative sequelae were identified in our subset of patients. Excellent survival and ventricular recovery are predicted.

Evolving strategies for surgical management of patients with severe left ventricular dysfunction

As a result of an increasing population with advanced congestive heart failure and the lack of growth in cardiac transplantation, surgical treatments for heart failure have been re-examined. These therapies represent the evolution of well-known operations such as coronary bypass surgery and valve surgeries, and the more novel left ventricular reconstruction and operations aimed at inhibiting left ventricular remodeling. When performed by surgeons with experience in this evolving speciality within cardiovascular surgery, surgery for advanced heart failure is a treatment of choice for many patients.

Synergistic approaches in the surgical treatment of heart failure: complex solutions for complex problems

In the current era, with a high incidence and prevalence of heart failure, cardiologists are developing a wide range of medical therapies for this population. Working in synergy with pharmacologic therapies, surgeons are developing several innovative surgical procedures to address mechanical problems in heart failure patients that will stabilize and reverse the complex problem of heart failure.