Durability and outcome of aortic valve replacement with mitral valve repair versus double valve replacement

Outcome of patients with double valve surgery between 2009 and 2018 at University Hospital Basel, Switzerland

Background

In isolated mitral valve regurgitation general consensus on surgery is to favor repair over replacement excluding rheumatic etiology or endocarditis. If concomitant aortic valve replacement is performed however, clinical evidence is more ambiguous and no explicit guidelines exist on the choice of mitral valve treatment. Both, double valve replacement (DVR) and aortic valve replacement in combination with concomitant mitral valve repair (AVR + MVP) have been proven to be feasible procedures. In our single-center, retrospective, observational cohort study, we compared the outcome of these two surgical techniques focusing on mortality and morbidity.

Methods

89 patients underwent DVR (n = 41) or AVR + MVP (n = 48) in our institution between 2009 and 2018. Follow-up data was collected using electronic patient records, by contacting treating physicians and by telephone interviews. We used the Kaplan–Meier method to analyze mortality during follow-up and Cox regression to investigate potential predictors of mortality.

Results

During a median follow-up duration of 4.5 [IQR 2.9 to 6.1] years, there was no significant difference in mortality between both cohorts. Thirty days mortality was 6.3% in the DVR and 7% in the AVR + MVP cohort. Overall mortality amounted to 17% for DVR and 23% for AVR + MVP. DVR was the preferred procedure for valve disease of rheumatic etiology and for endocarditis, while in degenerative valves AVR + MVP was predominant. More biological valves were used in the AVR + MVP cohort (p < 0.001) and more mechanical valves were implanted in the DVR cohort. The rate of rehospitalization, deterioration of left ventricular ejection fraction and postoperative complications were equally distributed among the two cohorts.

Conclusion

Our data analysis showed that both DVR and AVR + MVP are safe and feasible options for double valve surgery. Based on our findings we could not prove superiority of one surgical technique over the other. Choosing the appropriate procedure for the patient should be influenced by valve etiology, patients’ comorbidities and the surgeons’ experience.

Trial registration

This was a retrospectively registered trial, registered on April 1st 2018, ClinicalTrials.gov Identifier: NCT03667274.

In-hospital outcomes of patients undergoing concomitant aortic and mitral valve replacement in Germany

 

OBJECTIVES

To evaluate in-hospital outcomes of concomitant mitral valve replacement (MVR) in patients undergoing conventional aortic valve replacement due to aortic stenosis in a nationwide cohort.

METHODS

Administrative data from all patients with aortic stenosis undergoing conventional aortic and concomitant MVR (reason for MVR not specified) between 2017 and 2018 in Germany were analysed.

RESULTS

A total of 2597 patients with a preoperative logistic EuroScore of 9.81 (standard deviation: 8.56) were identified. In-hospital mortality was 6.8%. An in-hospital stroke occurred in 3.4%, acute kidney injury in 16.3%, prolonged mechanical ventilation of more than 48 h in 16.3%, postoperative delirium in 15.8% and postoperative pacemaker implantation in 7.6% of the patients. Mean hospital stay was 16.5 (standard deviation: 12.1) days. Age [odds ratio (OR): 1.03; P = 0.019], New York Heart Association class III or IV (OR: 1.63; P = 0.012), previous cardiac surgery (OR: 2.85, P = 0.002), peripheral vascular disease (OR: 2.01, P = 0.031), pulmonary hypertension (OR: 1.63, P = 0.042) and impaired renal function (glomerular filtration rate <15, OR: 3.58, P = 0.001; glomerular filtration rate <30, OR: 2.51, P = 0.037) were identified as independent predictors for in-hospital mortality.

CONCLUSIONS

In this nationwide analysis, concomitant aortic and MVR was associated with acceptable in-hospital mortality, morbidity and length of in-hospital stay. The regression analyses may help to identify high-risk patients and further optimize treatment strategies.

Considerations for prostheses choice in multiple valve surgery

OBJECTIVES

The prosthesis type for multiple valve surgery (replacement of two or more diseased native or prosthetic valves, replacement of two diseased valves with repair/reconstruction of a third, or replacement of a single diseased valve with repair/reconstruction of a second valve) remains inadequately evaluated. The clinical performance of multiple valve surgery with bioprostheses (BP) and mechanical prostheses (MP) was assessed to compare patient survival and composites of valve-related complications.

METHODS

Between 1975 and 2000, 1245 patients had multiple valve surgery (BP 785, mean age 62.0 ± 14.7 years; and MP 460, mean age 56.9 ± 12.9 years). There were 1712 procedures performed [BP 969(56.6%) and MP 743(43.4%). Concomitant coronary artery bypass (conCABG) was BP 206(21.3%) and MP 105(14.1%) (p = 0.0002). The cumulative follow-up was BP 5131 years and MP 3364 years. Independent predictors were determined for mortality, valve-related complications and composites of complications.

RESULTS

Unadjusted patient survival at 12 years was BP 52.1 ± 2.1% and MP 54.8 ± 4.6% (p = 0.1127), while the age adjusted survival was BP 48.7 ± 2.3% and MP 54.4 ± 5.0%. The predictors of overall mortality were age [Hazard Ratio (HR) 1.051, p < 0.0001], previous valve (HR 1.366, p = 0.028) and conCABG (HR 1.27, p = 0.021). The actual freedom from valve-related mortality at 12 years was BP 85.6 ± 1.6% and MP 91.0 ± 1.6% (actuarial p = 0.0167). The predictors of valve-related mortality were valve type (BP > MP) (2.61, p = 0.001), age (HR 1.032, p = 0.0005) and previous valve (HR 12.61, p < 0.0001). The actual freedom from valve-related reoperation at 12 years was BP 60.8 ± 1.9% and MP85.6 ± 2.1% (actuarial p < 0.001). The predictors of valve-related reoperation were valve type (MP > BP) (HR 0.32, p < 0.0001), age (HR 0.99, p = 0.0001) and previous valve (HR 1.38, p = 0.008) CONCLUSIONS: Overall survival (age adjusted) is differentiated by valve type over 10 and 12 years and valve-related mortality and valve-related reoperation favours the use of mechanical prostheses, overall for multiple valve surgery.

Acute coronary syndromes and atherosclerotic plaque burden distribution in coronary arteries among patients with valvular heart disease (BIA-WAD registry)

INTRODUCTION

Valvular heart diseases (VHD) are a significant problem in the Polish population. Coexistence of coronary artery disease (CAD) in patients with VHD increases the risk of death and affects the further therapeutic strategy.

AIM

Analysis of atherosclerotic plaque burden distribution in coronary arteries and long-term prognosis among patients with VHD.

MATERIAL AND METHODS

Inclusion criteria were met by 1025 patients with moderate and severe VHD. Mean observation time was 2528 ±1454 days.

RESULTS

Severe aortic valve stenosis (AVS) occurred in 28.2%, severe mitral valve insufficiency (MVI) in 20%. CAD with severe angiographic stenoses was noted in 42.3% (n = 434). Among patients with severe MVI, CAD was noted in 47.1% of cases, and prior acute coronary syndromes (ACS) in 27.1% of patients (n = 58). In severe AVS patients, significant angiographic atherosclerotic changes were observed in 29.6% (n = 86), and prior ACS in 7.6% (n = 22) of patients. During the observation 52.7% of patients died, including 62.9% of patients with severe MVI and 51.6% of those with severe AVS. Age (OR = 1.038; 95% CI: 1.005-1.072; p = 0.022) and coexisting aortic valve insufficiency (AVI) (OR = 2.39, 95% CI: 5.370-11.065, p = 0.035) increased the mortality rate.

CONCLUSIONS

Severe AVS is starting to be the most prevalent VHD. CAD is one of the most significant factors deteriorating prognosis of patients with VHD. AVI and age were significant risk factors for mortality. The worst prognosis was observed in severe MVI, which may result from more frequent occurrence of CAD in this group. A lesser burden of CAD and ACS in the group of patients with severe AVS did not affect survival.

Initial Experience of Minimally Invasive Concomitant Aortic and Mitral Valve Replacement/Repair at a Tertiary Care Cardiac Centre of a Developing Country

Introduction

Minimally invasive double valve replacement (DVR) surgery through a small transverse anterior thoracotomy is an alternate technique to sternotomy for concomitant aortic and mitral valve (AVR, MVR) surgery. The aim of this study was to evaluate the in-hospital and early outcomes of direct vision minimal invasive double valve surgery (DVMI-DVR) at a tertiary care cardiac center of a developing country.

Methods

This study was conducted at the National Institute of Cardiovascular Diseases Karachi, Pakistan from January 2018 to September 2018. Nineteen consecutive patients undergoing DVMI-DVR for aortic and mitral disease without any prior cardiac surgery were included in this study. For all procedures, access was obtained through small transverse anterior thoracotomy incision with wedge resection (Chaudhry’s Wedge) of sternum opposite to the third and fourth costosternal joints. Patients were observed during their hospital stay and the following variables were observed the length of hospital stay (LOHS), ventilator support, intensive care unit (ICU) stay, pain score, and mortality. The pain score was assessed using the visual analog scale (VAS).

Results

The male/female ratio was 11:8 with a mean age of 35 ± 12 years with mean EuroSCORE of 6.6 ± 3.5%. The mean total bypass time was 129.8 ± 23.83 min (range: 98-181 minutes). The mean mechanical ventilation time was 3.16 ± 1.12 hours (range: 2-6 hours). The mean intensive care unit (ICU) stay was 41.84 ± 8.36 hours. The mean post-operative LOHS was 5.63 ± 1.12 days (range: 4-8 days). We had zero frequency of wound infection and surgical mortality. The mean pain score was 4.32 (on a predefined pain scale of one to nine with a high value indicating severe pain).

Conclusion

Minimally invasive DVR surgery is a safe and reproducible technique with comparable outcomes such as postoperative pain score (4.32 ± 2.05), ventilation time (3.16 ± 1.12 hours), ICU stay (41.84 ± 8.36 hours), and hospital stay (5.63 ± 1.12 days). In terms of mortality, operative times, ICU stay, and hospital stay, the minimally invasive DVR is at least comparable to those achieved with median sternotomy. Further prospective randomized studies are needed to validate our findings.

Pathophysiology and management of combined aortic and mitral regurgitation

The combination of aortic and mitral regurgitation is a typical example of a frequent yet understudied multiple valve disease scenario. The aetiology is often rheumatic or degenerative; less frequently it can be induced by drugs or radiation, or caused by infective endocarditis or congenital valvular lesions. Aortic regurgitation resulting in secondary mitral regurgitation is also not uncommon. There are limited data to guide the management of combined aortic and mitral regurgitation. Left ventricular dysfunction is frequent at initial presentation, and even more so postoperatively, suggesting that surgical management should not be delayed, particularly when symptoms occur or when there is evidence of even subtle left ventricular dysfunction. The decision to operate on one or both valves not only depends on the severity of each lesion, but also on several other factors, including age, co-morbidities and frailty, the increased operative risk of double valve surgery, the increased risk of long-term thrombotic and bleeding complications with multiple mechanical valves, the risk of leaving one valve unoperated and the probability of requiring redo surgery. The role of a multidisciplinary heart valve team is critical in this setting to optimize management and outcomes. The role of transcatheter approaches is currently limited, but technological advances will probably soon change the management paradigm.

Long-term results after concomitant mitral and aortic valve surgery: repair or replacement?

OBJECTIVES

The reported superiority of mitral valve (MV) repair for isolated MV regurgitation has not been confirmed in mitroaortic valve surgery. Our goals were to evaluate the feasibility of repair in patients undergoing mitral and aortic valve surgery and to identify factors predisposing to MV replacement, to compare long-term outcomes (survival and MV reoperation) of repair and replacement and to perform a subgroup analysis in patients with rheumatic MV disease.

METHODS

From January 1992 through December 2016, 1122 consecutive patients were submitted to concomitant aortic and MV surgery in 2 different centres (Coimbra and Santiago). Of these, 837 patients underwent MV repair (74.6%) and 285 patients had MV replacement (25.4%). Rheumatic aetiology was predominant (666 patients; 59.4%). Cumulative follow-up was 9522.6 patient-years (25th-75th percentile 2.6-13.2 years) and was complete for 95.6% of patients. Propensity score matching (1:1) was performed in 232 patients for comparing each treatment option (MV repair and MV replacement).

RESULTS

Previous MV intervention, rheumatic aetiology, chronic obstructive pulmonary disease, higher degrees of tricuspid and mitral regurgitation and pulmonary hypertension were independently correlated with MV replacement. The 30-day mortality rate was higher in patients with MV replacement (4.2% vs 1.8%, P = 0.021) and was confirmed in the propensity score matching (4.7% vs 1.7%, P = 0.06). Late survival was lower in the MV replacement group (53.3 ± 4.5% vs 61.7 ± 2.0% at 12 years; P = 0.026) and was confirmed in the propensity score matching (54.6 ± 4.9% vs 63.2 ± 3.8%, P = 0.062) and rheumatic subgroup (57.9 ± 4.8% vs 68.0 ± 2.5%, P = 0.018). Freedom from MV reoperation at 12 years was higher in the MV repair group (94.7 ± 1.1% vs 89.0 ± 3.1%, P = 0.004) but similar in patients with rheumatic MV disease.

CONCLUSIONS

MV repair can be performed in most patients undergoing aortic valve replacement. It should be the procedure of choice whenever feasible, because it is associated with lower early and late mortality rates and with freedom from reoperation in non-rheumatic patients.

Pathophysiology and management of multivalvular disease

Multivalvular disease (MVD) is common among patients with valvular disease, and has a complex pathophysiology dependent on the specific combination of valve lesions. Diagnosis is challenging because several echocardiographic methods commonly used for the assessment of stenosis or regurgitation have been validated only in patients with single-valve disease. Decisions about the timing and type of treatment should be made by a multidisciplinary heart valve team, on a case-by-case basis. Several factors should be considered, including the severity and consequences of the MVD, the patient's life expectancy and comorbidities, the surgical risk associated with combined valve procedures, the long-term risk of morbidity and mortality associated with multiple valve prostheses, and the likelihood and risk of reoperation. The introduction of transcatheter valve therapies into clinical practice has provided new treatment options for patients with MVD, and decision-making algorithms on how to combine surgical and percutaneous treatment options are evolving rapidly. In this Review, we discuss the pathophysiology, diagnosis, and treatment of MVD, focusing on the combinations of valve pathologies that are most often encountered in clinical practice.

Outcomes of patients undergoing concomitant mitral and aortic valve surgery: results from an Italian regional cardiac surgery registry

OBJECTIVES

There are limited reliable data on the long-term survival of patients operated upon with double-valve surgery (DVS) in the literature. In this study, in-hospital mortality and 5-year survival were determined and the potential risk factors for increased mortality were identified and discussed.

METHODS

This is a report of an observational retrospective study of 1167 patients undergoing concomitant aortic and mitral valve surgery from 2002 to 2011. Data were prospectively collected in a regional database from Emilia-Romagna (Italy).

RESULTS

The overall in-hospital mortality rate for DVS was 6.9%. Both in-hospital and 1-year mortality were statistically significant between age groups. In-hospital mortality was significantly higher for patients with a smaller body mass index (BMI), for those who had concomitant coronary artery bypass grafting (CABG) and those who received mitral valve replacement (MVR) instead of plasty (MVP). In-hospital and 1-year mortality were highest in patients ≥70 who had implantation of mitral and aortic mechanical valves. There were significant differences in 5-year follow-up survival according to age, BMI and concomitant CABG. The choice of MVR and MVP did not affect 5-year survival. Multivariable analysis showed that patient-related factors appear to be the major determinant of late survival, irrespective of the type of operation or other intraoperative variables.

CONCLUSIONS

Advanced age, smaller BMI and concomitant CABG are significant risk factors for mortality in DVS. MVP provided comparable 5-year outcomes with MVR. Multivariable analysis demonstrates that preoperative and clinical patient-related factors are the real burden in the successful treatment of patients undergoing double-valve procedures.

Mitral valve repair versus replacement for moderate-to-severe mitral regurgitation in patients undergoing concomitant aortic valve replacement

OBJECTIVES

Whether to repair or replace the mitral valve for patients with significant mitral regurgitation undergoing aortic valve replacement is still controversial.

METHODS

From January 1990 to December 2011, a total of 663 patients underwent aortic valve replacement combined with mitral valve surgery. Among these, 253 patients (mean age 55.9 ± 14.5 years, 91 females) with moderate-to-severe mitral regurgitation were enrolled to compare the outcomes between double valve replacement (DVR group, n = 158) and aortic valve replacement plus mitral valve repair (AVR plus MVr group, n = 95). Survival and valve-related events were compared by the inverse-probability-treatment-weighted method using propensity scores to reduce treatment selection bias.

RESULTS

Early mortality was similar between the groups (1.9% in the DVR group when compared with 3.2% in the AVR plus MVr group, P = 0.55). During the mean follow-up period of 72.1 ± 56.7 months, 45 patients died (28 in DVR and 17 in AVR plus MVr) and 31 experienced valve-related events including valve reoperation in 11, anticoagulation-related bleeding in 14, thromboembolism complications in 9 and infective endocarditis in 3. After adjustment for baseline risk profiles, the DVR group showed no difference with regard to risks of death (hazard ratio [HR], 1.79; 95% confidence interval [CI], 0.79-4.01; P = 0.16) and valve-related events (HR, 1.15; 95% CI, 0.40-3.30; P = 0.80) compared with the AVR plus MVr group.

CONCLUSIONS

Although the outcomes of either mitral valve repair or replacement for moderate-to-severe mitral regurgitation in patients undergoing concomitant aortic valve replacement show no statistical significance in terms of long-term survival and valve-related event rates, DVR seems more hazardous than AVR plus MVr based on the estimated HR in terms of survival.

In patients with concomitant aortic and mitral valve disease is aortic valve replacement with mitral valve repair superior to double valve replacement?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: in patients with concomitant aortic and mitral valve disease is aortic valve replacement with mitral valve plasty (MVP) superior to double valve replacement (DVR) in terms of improved long-term survival? Altogether 156 papers were found using the reported search, of which seven represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Out of seven papers, that simultaneously compare these two treatment modalities, three favor MVP combined with aortic valve replacement (AVR) over DVR, two papers advocate the opposite and two failed to find any significant difference in long-term survival, freedom from reoperation and thromboembolic and bleeding complications between these two surgical options. All data presented derive from level 2b evidence. Critical appraisal of these studies is constricted by the large heterogeneity of the patients, diversity in treatment protocols and inherent selection bias. We conclude that currently the available evidence is insufficient to prove that AVR with MVP is superior to DVR in patients with double valve disease.

International normalized ratio self-management lowers the risk of thromboembolic events after prosthetic heart valve replacement

BACKGROUND

Although prosthetic valves are durable and easy to implant, the need for lifetime warfarin-based anticoagulation restricts their exclusive usage. We investigated if anticoagulation self-management improves outcome in a single-center series.

METHODS

Between 1994 and 1998, 765 patients with prosthetic valve replacements were prospectively enrolled and randomized to receive conventional anticoagulation management by their primary physician (group 1, n = 295) or to pursue anticoagulation self-management (group 2, n = 470). A study head office was implemented to coordinate and monitor anticoagulation protocols, international normalized ratios (INR), and adverse events. Patients were instructed on how to obtain and test their own blood samples and to adjust warfarin dosages according to the measured INR (target range, 2.5 to 4).

RESULTS

Mean INR values were slightly yet significantly smaller in group 1 than in group 2 (2.8 +/- 0.7 vs 3.0 +/- .6, p < 0.001). Moreover, INR values of patients with conventional INR management were frequently measured outside the INR target range, whereas those with anticoagulation self-management mostly remained within the range (35% vs 21%, p < 0.001). In addition, the scatter of INR values was smaller if self-managed. Freedom from thromboembolism at 3, 12, and 24 months, respectively, was 99%, 95%, and 91% in group 1 compared with 99%, 98%, and 96% in group 2 (p = 0.008). Bleeding events were similar in both groups. Time-related multivariate analysis identified INR self-management and higher INR as independent predictors for better outcome.

CONCLUSIONS

Anticoagulation self-management can improve INR profiles up to 2 years after prosthetic valve replacement and reduce adverse events. Current indications of prosthetic rather than biologic valve implantations may be extended if the benefit of INR self-management is shown by future studies with longer follow-up.

Aortic Valve Replacement With Mitral Valve Repair Compared With Combined Aortic and Mitral Valve Replacement

BACKGROUND

Double valve replacement is associated with reduced long-term survival. This study investigates aortic valve replacement with mitral valve repair as an alternative to double valve replacement in patients with rheumatic heart disease (RHD).

METHODS

Between January 1995 and December 2005, 369 patients with RHD underwent combined aortic and mitral valve procedures. In 76 patients (20.6%), mitral valve repair with aortic valve replacement (group 1) was done. The remaining 293 patients (79.4%) underwent double valve replacement (group 2). A total of 351 patients (95%)--73 (96%) in group 1 and 278 (94.8%) in group 2--were 50 years of age or younger.

RESULTS

There was no difference in early mortality in the groups (4 in group 1 versus 25 in group 2, p = 0.35). The median follow-up was 60 months (range, 6 to 132 months) and 96% complete in group 1 and 92% in group 2. Actuarial survival was 90.5% +/- 3.4% in group 1 and 81.60% +/- 2.4% in group 2 at 60 months (p = 0.07). Event-free survival at 60 months was 78.3% +/- 5.1% in group 1 and 48.4 % +/- 3.2% in group 2 (p < 0.001). Reoperation-free survival was 92.5% +/- 0.4% in group 1 and 99.5% +/- 0.05% in group 2 (p = 0.014).

CONCLUSIONS

Mitral valve repair with aortic valve replacement provides significantly better event-free survival than double valve replacement without a better actuarial survival. Reoperation rates are higher in the mitral valve repair and aortic valve replacement group, whereas thromboembolic complications were more in the double valve replacement group. Better event-free survival in patients undergoing mitral valve repair and aortic valve replacement still argues in favor of repair of the mitral valve whenever possible.

Concomitant mitral valve surgery with aortic valve replacement: a 21-year experience with a single mechanical prosthesis

Background

Long-term survival for combined aortic and mitral valve replacement appears to be determined by the mitral valve prosthesis from our previous studies. This 21-year retrospective study assess long-term outcome and durability of aortic valve replacement (AVR) with either concomitant mitral valve replacement (MVR) or mitral valve repair (MVrep). We consider only a single mechanical prosthesis.

Methods

Three hundred and sixteen patients underwent double valve replacement (DVR) (n = 273) or AVR+MVrep (n = 43), in the period 1977 to 1997. Follow up of 100% was achieved via telephone questionnaire and review of patients' medical records. Actuarial analysis of long-term survival was determined by Kaplan-Meier method. The Cox regression model was used to evaluate potential predictors of mortality.

Results

There were seventeen cases (5.4%) of early mortality and ninety-six cases of late mortality. Fifteen-year survival was similar in both groups at 44% and 57% for DVR and AVR+MVrep respectively. There were no significant differences in valve related deaths, anticoagulation related complications, or prosthetic valve endocarditis between the groups. There were 6 cases of periprosthetic leak in the DVR group. Sex, pre-operative mitral and aortic valve pathology or previous cardiac surgery did not significantly affect outcome.

Conclusion

The mitral valve appears to be the determinant of survival following double valve surgery and survival is not significantly influenced by mitral valve repair.

Mitral valve repair versus replacement in simultaneous mitral and aortic valve surgery for rheumatic disease

BACKGROUND

The purpose of this study was to compare the late results of combined mitral valve repair and aortic valve replacement with double valve replacement for patients with rheumatic heart disease.

METHODS

From 1981 to 2003, 128 patients underwent aortic valve replacement with either mitral valve repair (n = 47) or mitral valve replacement (n = 81) for rheumatic disease. Mean follow-up was 9.1 +/- 4.5 years.

RESULTS

Rates of actuarial freedom from cardiac-related death (81.4% versus 75.9% at 12 years; p = 0.60), thromboembolism (79.8% versus 85.1% at 12 years; p = 0.78), and bleeding (97.3% versus 95.7% at 12 years; p = 0.77) were similar in both combined mitral valve repair and aortic valve replacement and double valve replacement. However, freedom from mitral valve reoperation was significantly lower in combined mitral valve repair and aortic valve replacement compared with double valve replacement (52.6% versus 76.8% at 12 years; p = 0.002). Mitral valve repair (p = 0.002) and mitral bioprosthesis (p = 0.0001) were independent risk factors for mitral valve reoperation.

CONCLUSIONS

Potential advantages of preserving, rather than replacing, the native mitral valve, such as better cardiac survival or fewer thromboembolic complications, were not identified in combined mitral valve repair and aortic valve replacement compared with double valve replacement for patients with rheumatic disease. Indeed, combined mitral valve repair and aortic valve replacement was associated with a significantly higher incidence of mitral valve reoperation. Therefore, in double valve surgery for rheumatic disease, mitral valve repair should be limited to the correction of mitral valve lesions only when excellent durability can be expected.

A review of the application of propensity score methods yielded increasing use, advantages in specific settings, but not substantially different estimates compared with conventional multivariable methods

OBJECTIVE

Propensity score (PS) analyses attempt to control for confounding in nonexperimental studies by adjusting for the likelihood that a given patient is exposed. Such analyses have been proposed to address confounding by indication, but there is little empirical evidence that they achieve better control than conventional multivariate outcome modeling.

STUDY DESIGN AND METHODS

Using PubMed and Science Citation Index, we assessed the use of propensity scores over time and critically evaluated studies published through 2003.

RESULTS

Use of propensity scores increased from a total of 8 reports before 1998 to 71 in 2003. Most of the 177 published studies abstracted assessed medications (N=60) or surgical interventions (N=51), mainly in cardiology and cardiac surgery (N=90). Whether PS methods or conventional outcome models were used to control for confounding had little effect on results in those studies in which such comparison was possible. Only 9 of 69 studies (13%) had an effect estimate that differed by more than 20% from that obtained with a conventional outcome model in all PS analyses presented.

CONCLUSIONS

Publication of results based on propensity score methods has increased dramatically, but there is little evidence that these methods yield substantially different estimates compared with conventional multivariable methods.

Mitral valve repair or replacement in elderly people

PURPOSE OF REVIEW

Much has been published so far to describe and praise the benefits of mitral valve repair, and to compare it with valve replacement. Now, with mitral valve surgery in elderly people gaining greater acceptance worldwide, repair or replacement remains a controversial issue. This is especially true in the ageing population, in whom many of the complications associated with a mechanical valve can be avoided by using a bioprosthesis. This review will try to assess the latest views in the field and come up with possible answers to this ongoing question.

RECENT FINDINGS

The causes of mitral regurgitation in this age group are separately reviewed and discussed in the light of our better understanding of the pathophysiology of the disease. Mitral surgery is recommended when the effective regurgitant orifice reaches 40 mm. Repair in degenerative disease seems to be feasible, with good long-term results. In chronic ischaemic regurgitation, the concept of a tethered 'normal valve' is changing. The 'poor' ventricle may be able to withstand surgery as long as the subvalvular apparatus is preserved; on the other hand, repair and replacement seem to have the same survival advantage in high-risk patients.

SUMMARY

Mitral valve surgery is well tolerated in elderly people. Early intervention leads inevitably to better outcome. The majority of valvular disorders in this age group are amenable to repair, with good reproducible results. Replacement with a bioprosthesis remains a viable option for complex regurgitant jets.

Mitral valve repair with aortic valve replacement in rheumatic heart disease

From 1992 to 2001, 609 patients with rheumatic heart disease underwent aortic valve replacement with either mitral valve repair (n = 201) or mitral valve replacement (n = 408). Follow-up extended to 10 years. Thirty-day mortality was 1.4% for mitral valve repair and 0.7% for mitral valve replacement (p = 0.4). Survival at 9 years was 96.5 +/- 1.4% after mitral valve repair and 89.7 +/- 7.8% after mitral valve replacement (p = 0.73). Freedom from major bleeding at 9 years was 94.8 +/- 2.4% after mitral valve repair and 81 +/- 7.2% after mitral valve replacement (p = 0.03). Freedom from other valve-related complications and from mitral valve re-operation was similar for the two groups. This study showed that in patients with rheumatic heart disease the results of mitral valve repair with aortic valve replacement were comparable to those of double valve replacement. Major bleeding was less frequent after mitral valve repair with aortic valve replacement. Therefore, whenever feasible, mitral valve repair should be attempted in patients with rheumatic heart disease who need concomitant aortic valve replacement.