Reduced survival in women after valve surgery for aortic regurgitation: effect of aortic enlargement and late aortic rupture

Sex-based differences in left ventricular remodeling in patients with chronic aortic regurgitation: a multi-modality study

BACKGROUND

Significant aortic regurgitation (AR) leads to left ventricular (LV) remodeling; however, little data exist regarding sex-based differences in LV remodeling in this setting. We sought to compare LV remodeling and AR severity, assessed by echocardiography and cardiovascular magnetic resonance (CMR), to discern sex-based differences.

METHODS

Patients with ≥ moderate chronic AR by echocardiography who underwent CMR within 90 days between December 2005 and October 2015 were included. Nonlinear regression models were built to assess the effect of AR regurgitant fraction (RF) on LV remodeling. A generalized linear model and Bland Altman analyses were constructed to evaluate differences between CMR and echocardiography. Referral for surgical intervention based on symptoms and LV remodeling was evaluated.

RESULTS

Of the 243 patients (48.3 ± 16.6 years, 58 (24%) female), 119 (49%) underwent surgical intervention with a primary indication of severe AR, 97 (82%) men, 22 (18%) women. Significant sex differences in LV remodeling emerged on CMR. Women demonstrated significantly smaller LV end-diastolic volume index (LVEDVI) (96.8 ml/m2 vs 125.6 ml/m2, p < 0.001), LV end-systolic volume index (LVESVI) (41.1 vs 54.5 ml/m2, p < 0.001), blunted LV dilation in the setting of increasing AR severity (LVEDVI p value < 0.001, LVESVI p value 0.011), and LV length indexed (8.32 vs 9.69 cm, p < 0.001). On Bland Altman analysis, a significant interaction with sex and LV diameters was evident, demonstrating a significant increase in the difference between CMR and echocardiography measurements as the LV enlarged in women: LVEDVI (p = 0.006), LVESVI (p < 0.001), such that echocardiographic measurements increasingly underestimated LV diameters in women as the LV enlarged. LV length was higher for males with a linear effect from RF (p < 0.001), with LV length increasing at a higher rate with increasing RF for males compared to females (two-way interaction with sex p = 0.005). Sphericity volume index was higher for men after adjusting for a relative wall thickness (p = 0.033).

CONCLUSIONS

CMR assessment of chronic AR revealed significant sex differences in LV remodeling and significant echocardiographic underestimation of LV dilation, particularly in women. Defining optimal sex-based CMR thresholds for surgical referral should be further developed.

TRIAL REGISTRATION

NA.

Sex Differences in Outcomes of Patients With Chronic Aortic Regurgitation: Closing the Mortality Gap

OBJECTIVE

To examine contemporary clinical differences between men and women with hemodynamically significant chronic aortic regurgitation (AR).

PATIENTS AND METHODS

We retrospectively identified 1072 consecutive patients with moderate to severe or severe AR diagnosed between February 21, 2004, and April 29, 2019. Echocardiographic data, aortic valve surgical intervention (AVS), and all-cause death were analyzed.

RESULTS

At baseline, the 189 women in the study group were older than the 883 men (mean ± SD age, 64±18 years vs 58±17 years), had more advanced symptoms, and had larger left ventricular end-systolic dimension index (LVESDi) (all P<.001) despite similar AR severity. An LVESDi of greater than 20 mm/m² was noted in 60 of 92 asymptomatic women (65%) vs 225 of 559 asymptomatic men (40%) (P<.001). Median follow-up was 5.6 years (interquartile range, 2.5 to 10.0 years). Female sex was associated with less AVS (P=.009), and overall 10-year survival was better in men (76%±2%) than in women (64%±5%) (P=.004). However, 10-year post-AVS survival was similar between the sexes (P=.86), and women had better left ventricular reverse remodeling than men regarding end-diastolic dimension (P=.02). Multivariable independent predictors of death were age, advanced symptoms, LVESDi, ejection fraction, and AVS (all P≤.03) but not female sex. When compared with the age-matched US population, women exhibited a 1.3-fold increased relative risk of death (P=.0383) while men had similar survival (P=.11).

CONCLUSION

In contemporary practice, women with AR continue to exhibit an overall survival penalty not related to female sex but to late referral markers, including more advanced symptoms, larger LVESDi, and less AVS. Nonetheless, women in our study exhibited outstanding post-AVS left ventricular remodeling and had good post-AVS survival, a step forward toward closing the sex-related mortality gap. The high percentage of LVESDi of 20 mm/m² or greater in asymptomatic women represents a window of opportunity for advanced-symptom prevention and timely AR surgical correction that may close the mortality gap.

Blunted beta-adrenoceptor-mediated inotropy in valvular cardiomyopathy: another piece of the puzzle in human aortic valve disease

OBJECTIVES

Heart failure induced by valvular cardiomyopathy occurs in a substantial proportion of patients undergoing heart valve surgery. We aimed (i) to quantify beta-adrenoceptor (beta-AR) function by measuring the inotropic effect of isoprenaline in left ventricular (LV) tissue and (ii) to correlate beta-AR-mediated inotropy with clinical markers of heart failure.

METHODS

A total of 179 LV myocardial samples were obtained from 104 consecutive patients who underwent aortic valve (AV) surgery between 2017 and 2019. Beta-ARs were stimulated by increasing the concentrations of isoprenaline, followed by a single high concentration of forskolin and calcium. Beta-AR sensitivity was estimated as the concentration to achieve half maximum effects (EC50). Maximum effect size was calculated as the relative beta-AR-mediated inotropic response compared to the force in the presence of high calcium [FISO/Ca (%)]. In vitro data were correlated with the clinical indicators of LV disease.

RESULTS

FISO/Ca was independent of age and sex and amounted to 79.6 ± 20.5%. In a multivariate regression model, we found a significant inverse association between FISO/Ca and preoperative left ventricular end-diastolic diameter increase per 10 mm (OR -9.24, 95% CI -16.66 to -1.82; P = 0.015). Furthermore, patients with end-stage heart failure showed a strong tendency towards more severe reduction of max beta-AR response, as indicated by reduced FISO/Ca in a multivariate model (OR -29.60, 95% CI -61.92 to 2.72; P = 0.055).

CONCLUSIONS

Our study indicates that in vitro myocardial contractility testing can quantify beta-AR dysfunction in patients with AV disease. We found a significant association between reduced beta-AR sensitivity and increased LV diameter, which may indicate a role of beta-AR dysfunction in the development of heart failure in patients with AV disease.

Sex-Related Anatomical Feasibility Differences in Endovascular Repair of Thoracoabdominal Aortic Aneurysms With a Multibranched Stent-Graft

Purpose:

To evaluate the potential anatomical feasibility of using the off-the-shelf multibranched Zenith t-Branch for the treatment of thoracoabdominal aortic aneurysms (TAAAs) in female patients.

Materials and Methods:

A total of 268 patients (median age 68 years; 69 women) with degenerative TAAA treated at a single institution by means of open or endovascular repair between 2007 and 2019 were retrospectively analyzed to determine the feasibility of using the Zenith t-Branch based on the manufacturer’s instructions for use. The factors determining overall anatomical feasibility were divided into vascular access, aortic anatomy, and visceral vessels. The results were stratified by sex and compared. A logistic regression model was constructed to determine any association between feasibility and clinical factors or potential confounding variables; results are expressed as the odds ratio (OR) with 95% confidence interval (CI).

Results:

The overall anatomical feasibility was 39% (22% women vs 45% men, p=0.001). The feasibility was negatively influenced by female sex (p<0.001) in multivariable analysis (OR 2.9, 95% CI 1.5 to 5.4, p=0.001). Vascular access feasibility was 82% (61% women vs 89% men, p<0.001). Aorta feasibility was 65% (52% women vs 69% men, p<0.001), and visceral vessel feasibility was 74% (78% women vs 73% men, p=0.260). An access diameter ≤8.5 mm excluded 17% of the patients (39% women vs 9% men, p<0.001). The aortic feasibility was limited by the infrarenal aortic diameter in 16% of patients (45% women vs 6% men, p<0.001) and the aortic lumen at the visceral vessels in 17% patients (19% women vs 17% men, p=0.741). The visceral vessel feasibility was mainly limited by inadequate numbers or diameters of target vessels. Location and orientation of the target vessels were adequate in 96% of patients.

Conclusion:

A little more than a third of an all-comers cohort of patients with degenerative TAAA could have been treated with on-label use of the Zenith t-Branch. However, only 22% of women could have been treated because of sex-related anatomical limitations. New generations of multibranched devices should address these differences.

Are outcomes of thoracoabdominal aortic aneurysm repair different in men versus women? A propensity-matched comparison

OBJECTIVE

Women fare worse than men after many cardiovascular operations, including coronary artery bypass grafting and valve surgery. We sought to determine whether sex affects outcomes after open thoracoabdominal aortic aneurysm repair.

METHODS

We evaluated data on 3353 consecutive patients (1281 women, 38.2%) who underwent open thoracoabdominal aortic aneurysm repair between October 1986 and July 2015. We compared preoperative characteristics, surgical variables, and outcomes between men and women in the overall group. A propensity-matching analysis was performed to adjust for preoperative and intraoperative differences. A multivariable analysis was conducted to identify predictors of poor outcomes using relevant preoperative and intraoperative factors.

RESULTS

Men had a significantly higher prevalence of comorbid conditions, including coronary artery disease, and presented more often with dissection; women were slightly older than men (median age, 69 [62-74] years vs 67 [57-73] years; P < .001) and more often symptomatic. Men underwent extent II and IV repairs more often, whereas women more often had extent I and III repairs. The propensity analysis resulted in 958 matched pairs. Overall, women and men had similar early mortality (7.9% vs 7.2%, P = .5) and adverse event rates (14.8% vs 14.1%, P = .6), which were similar in propensity-matched groups. Multivariable analysis showed that predictors of operative death and adverse event differed between the sexes. Survival and freedom from repair failure were similar between the overall and matched groups.

CONCLUSIONS

Men and women who undergo thoracoabdominal aortic aneurysm repair have similar outcomes, but there are important differences in several perioperative factors and predictors of poor outcomes.

Statin Use and Aneurysm Risk in Patients With Bicuspid Aortic Valve Disease

BACKGROUND

No medical therapy has been proven to prevent the progression of aortic dilatation in bicuspid aortic valve (BAV) disease, and prophylactic aortic surgery remains the mainstay of treatment.

HYPOTHESIS

Among patients with BAV disease who are referred for surgery, preoperative statin use is associated with decreased odds of ascending aortic dilatation.

METHODS

We reviewed all BAV patients who underwent aortic valve and/or aortic surgery at our center between April 2004 and December 2013. Aortic diameter (AD), defined as the maximum ascending aortic dimension, was determined by magnetic resonance imaging, computed tomography, or echocardiography. Patients were divided into 2 groups: maximal AD <4.5 cm or ≥4.5 cm. The association between preoperative statin use and aortic dilatation was assessed using multivariable logistic regression modeling.

RESULTS

Of 680 consecutive patients, 405 (60%) had AD <4.5 cm (mean age, 60 ± 14 years; 45% on statins), whereas 275 (40%) had AD ≥4.5 cm (mean age, 54 ± 13 years; 35% on statins) at the time of surgery. After adjusting for age, body surface area, sex, hypertension, aortic stenosis, severity of aortic regurgitation, and use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and β-blockers, patients with AD ≥4.5 cm had 0.66× lower odds (95% confidence interval: 0.45-0.96) of being on preoperative statins compared with those with AD <4.5 cm (P = 0.029).

CONCLUSIONS

In a retrospective study of BAV patients referred for surgery, preoperative statin use was associated with lower odds of clinically significant ascending aortic dilatation.

Gender differences in outcomes following cardiac surgery: implications for managing patients with mitral valve disease

PURPOSE OF REVIEW

This review summarizes the differences in clinical outcomes following cardiac surgery according to gender.

RECENT FINDINGS

Women comprise a large proportion of patients presenting with coronary artery or valvular heart disease. Although it is well known that women have poorer survival following bypass surgery compared with men, more recent data confirm that women also have poorer outcomes after heart valve surgery. Women are also more likely to receive mitral valve replacement instead of repair, when compared with men. These divergent outcomes are because of many factors, including valve disease and clinical presentation, which may result in delayed surgical referral in women.

SUMMARY

Factors that result in poorer outcomes following heart valve surgery, including mitral valve surgery, between men and women remain incompletely understood. These may relate to differences in clinical presentation, valve morphology, and physiology. Further research is needed to clarify differences in heart valve outcomes according to gender.

Risk of proximal aortic dissection in patients with bicuspid aortic valve: how to address this controversy?

The risk of acute aortic events in patients with bicuspid aortic valve (BAV) disease is a controversial issue. The real risk of aortic dissection in patients with BAV disease is unknown. An indirect assessment of this risk, however, could be gained with a more detailed understanding of the pathogenesis of BAV aortopathy. There are two major issues that should be clarified before one addresses the question of aortic dissection risk in BAV patients. The first issue, when analysing the data from previous BAV cohorts, is to determine what stage of BAV disease was present in the described patient population. In particular, was the risk of aortic dissection in BAV patients determined before or after aortic valve replacement (AVR) surgery? The second issue to consider is the functional state of the pathological valve within the observed population. In particular, did patients predominantly suffer from BAV stenosis or BAV insufficiency? Unfortunately, the vast majority of published reports do not separate between the different BAV phenotypes, thereby complicating interpretation of the results. Considering these two important clinical variables (i.e. the stage of BAV disease and the functional phenotype), we herein aim to explain the inconsistency of the published data with regard to the risk of aortic dissection in patients with BAV disease.

Gender Analysis After Elective Open Heart Surgery: A Two-Year Comparative Study of Quality of Life

BACKGROUND

The aim of this prospective study, based on the iterative completion of the 36-item short form health survey questionnaire (SF36) after open heart surgery, was twofold: to evaluate the changes in quality of life (QOL) scores (over time and by gender, and also in comparison with scores from a normal population) and to identify possible gender differences in two-year cardiac functional status.

METHODS

From July 2000 to July 2002, 590 elective patients were included in this study. Baseline and follow-up QOL surveys were obtained for 439 patients (307 males and 132 females). The QOL scores were compared by gender, by analysis of variance, and by the Student t test. Factors influencing two-year cardiac functional status were determined by logistic regression.

RESULTS

The comparison of baseline and follow-up scores showed a significant improvement (a sharp increase between baseline and year one, then stabilization) in all dimensions of the SF36, two years after surgery in all patients. However, QOL was significantly lower in women than in men in all but two dimensions; at baseline and during follow-up. When compared with the normal population, men and women over 75 had a similar QOL. The best independent predictive factor of two-year cardiac functional status in women was the physical component summary score and in men, the mental component summary score.

CONCLUSIONS

The benefit of open heart surgery at two-year follow-up is equivalent in both genders in terms of QOL, although women had lower baseline QOL scores.

Aortic root growth in men and women with the Marfan's syndrome

The leading cause of premature death in patients with Marfan's syndrome (MS) is type A aortic dissection or rupture due to progressive aortic root dilation. The aim of this study was to analyze aortic root growth in 113 men and 108 women with MS. All patients were prospectively followed with serial echocardiograms of the native aortic root. At baseline, women had on average a 5-mm smaller aortic root diameter adjusted for age than men. Average aortic root growth was 0.42 mm/year (SE 0.05) in men and 0.38 mm/year (SE 0.04) in women. On the basis of aortic root growth rates, the men and women could be divided into 2 normally distributed subgroups: fast and slow growers. Approximately 1 in 7 men (1.5 mm/year, SE 0.5) and approximately 1 in 9 women (1.8 mm/year, SE 0.3) had fast-growing aortic root diameters. Significantly more type A dissections (25% vs 4%, p <0.001) were observed in fast growers than in slow growers; this was found in men and women. Type A dissections were observed in 4 men and 9 women. By reducing the cut-off value by 5 mm for elective aortic root replacement in women, type A dissections could have been prevented in 3 women. In conclusion, guidelines should take gender differences into account, and therefore, the investigators propose reducing the threshold for elective aortic root replacement in women with MS by 5 mm.

Are patients with isolated chronic aortic regurgitation operated in time? Analysis of survival data over a decade

BACKGROUND

Patients suffering from chronic isolated aortic regurgitation have a less favorable outcome than patients with aortic stenosis. According to international recommendations, these patients should undergo surgery as soon as left ventricular function begins to deteriorate, that is, surgery is not to be postponed until clinical symptoms become relevant.

HYPOTHESIS

The study was undertaken to evaluate how satisfactory our timing of surgery was, as reflected by survival data.

METHODS

Survival was studied retrospectively in a consecutive series of patients undergoing surgery for chronic isolated aortic regurgitation during a 10-year period in our institution. Results were compared with data from the literature. By excluding patients with aortic aneurysms and acute endocarditis, we formed a homogeneous patient group of 88 subjects.

RESULTS

Thirty-day mortality was 1% and late mortality after a mean follow-up period of 6 years was 11%. Compared with survival data from an earlier study in which the patient population was similar and resided in the same geographic area, the results in our patient group seem to be better. It is noteworthy that despite a strong effort to recommend surgery at an earlier stage of the disease than previously, 35% of the patients had moderate or severe left ventricular dysfunction preoperatively because of late referrals.

CONCLUSION

This stresses the importance of early detection and careful preoperative follow-up with noninvasive methods in patients with aortic regurgitation.

Aortic Dissection After Previous Cardiovascular Surgery

BACKGROUND

Risk of repairing aortic dissection after previous cardiovascular surgery has not been described clearly. This study assesses early and late outcomes of such reoperations.

METHODS

From January 1, 1990, to January 1, 2002, 108 patients with prior cardiovascular surgery (isolated coronary artery bypass grafting, 51%; isolated valve surgery, 21%; aortic aneurysm repair, 24%; and combinations of these in the remainder) underwent reoperation for aortic dissection (emergency operation for acute dissection in 24%). Mean age was 63 +/- 13 years, and 85% were men. The interval since prior surgery ranged from 10 days to 22 years (median, 3.8 years). This was the third operation for 8%. Ascending aortic repair with or without aortic arch or descending aortic repair was performed in 40%, aortic valve replacement (n = 15) or repair (n = 17) with ascending aortic repair in 30%, aortic root replacement with or without aortic arch or descending aortic repair in 30%, and aortic arch with or without descending aortic repair in 1%. Circulatory arrest was used in 78%, with retrograde brain perfusion in 58%.

RESULTS

Hospital mortality was 6%, stroke 4%, renal failure 2%, and respiratory failure 7%. Survival at 30 days and 1, 3, 5, and 7 years was 93%, 85%, 74%, 63%, and 53%, respectively. Aortic reoperation was performed in 7 patients, with freedom from this event at 30 days and 1, 3, 5, and 7 years of 98%, 95%, 93%, 91%, and 89%., respectively

CONCLUSIONS

Aortic dissection after cardiovascular surgery is rare and can be managed with acceptable operative risks and good long-term survival. Need for subsequent aortic reoperation is uncommon.

Transarterial aortic valve replacement with a self expanding stent in pigs

OBJECTIVES

To evaluate the feasibility of percutaneous aortic valve replacement without cardiac arrest in animal experiments.

METHODS

A self expanding nitinol stent, containing pulmonary valves from pigs in its proximal part, was implanted in six pigs (94-118 kg) by means of a 25 French catheter through the left subclavian artery under guidance of fluoroscopy and transoesophageal echocardiography. During stent deployment the original aortic valve was pushed against the aortic wall by the self expanding force of the stent while the new valve was expanded.

RESULTS

It was possible to replace the aortic valve in the beating heart in four pigs (67%) with no complication or relevant drop in blood pressure. The procedure failed in two pigs (33%) due to dysfunction of the catheter device in one case and to problems with correct positioning in the left ventricular outflow tract in the other. After successful stent valve implantation, dopamine was infused in doses of 5 microg/kg/min, 10 microg/kg/min, and 15 microg/kg/min. Cardiac output increased from 4.4 to 8.8 l/min and the mean arterial pressure rose from 79 to 105 mm Hg. The maximum peak to peak pressure gradient across the valve carrying stent reached a maximum of 8 mm Hg under dopamine infusion. All pigs were killed six hours after transvascular aortic valve replacement. The chest was opened, and the left ventricle and the ascending aorta were carefully inspected. There were no signs of malfunction of the implant, of damage of the aortic vessel wall, or of obstruction of the coronary ostia.

CONCLUSIONS

Percutaneous aortic valve replacement with a self expanding nitinol stent in the beating heart is possible. The device was safe under pharmacological stress test. After successful chronic animal experiments, this concept may become a feasible option for treating patients with relevant aortic valve disease but where open heart surgery would be risky.

Aortic root replacement versus aortic valve replacement: a case-match study

BACKGROUND

There is increasing evidence that patients with aortic valve disease and dilatation of the ascending aorta are at risk for later dissection or rupture of the aortic wall when the dilated ascending aorta is not replaced or reinforced at the time of aortic valve replacement. In order to find out whether the more complex surgical procedure of aortic root replacement carries a higher early or late postoperative risk than isolated aortic valve replacement, we conducted a matched-pair study with patients of both groups.

METHODS

Between June 1993 and August 1998, 100 consecutive patients with aortic valve disease and ectasia/aneurysm of the ascending aorta underwent replacement of the aortic valve and the ascending aorta with a CarboSeal composite graft (CarboSeal; Sulzer Carbo-Medics Inc, Austin, TX). Identical bileaflet valve prostheses (CarboMedics; Sulzer CarboMedics Inc, Austin, TX) were implanted during the same time period in 928 patients for aortic valve disease. On the basis of various preoperative clinical variables 100 patients with aortic valve replacement were matched to the 100 patients with replacement of the aortic root. The duration of follow-up for both groups was similar with 37 + 17 months (range, 9 to 70) for the CarboSeal group and 38 + 14 months (range, 13 to 65) for the CarboMedics group. Survival and morbidity were calculated by Kaplan-Meier analysis and risk-adjusted mortality was evaluated by multivariate analysis in a Cox regression model.

RESULTS

The early postoperative mortality of 1% in the CarboSeal group and 4% in the CarboMedics group was insignificantly different. Although the overall survival rate at 5 years was lower (60.7% vs 86.3%; p = 0.13) in the CarboSeal group, the freedom from cardiac mortality and valve-related morbidity was similar in the two groups.

CONCLUSIONS

Replacement of the ascending aorta and aortic valve can be performed with similar operative risk, valve-related morbidity, and late cardiac mortality as isolated aortic valve replacement.