Long-Term Survival After Surgical Revascularization for Moderate Ischemic Mitral Regurgitation

doi:10.1016/j.athoracsur.2005.03.034

The Annals of Thoracic Surgery

Volume 80, Issue 2, August 2005, Pages 570-577

https://doi.org/10.1016/j.athoracsur.2005.03.034 Get rights and content

Background

We sought to characterize patient survival and degree of late mitral regurgitation (MR) in patients undergoing surgical revascularization with moderate ischemic MR.

Methods

We retrospectively reviewed 251 patients undergoing coronary artery bypass graft (CABG) surgery between 1991 and 2001 with 3+ ischemic MR, including 31 patients who had concomitant mitral annuloplasty. Univariate and multivariable testing was employed.

Results

Actuarial 1-, 5-, and 10-year survival was 84.0%, 67.5%, and 37.1% in the overall group of 251 patients. Independent predictors of long-term mortality were age 70 years or more (hazard ratio 2.50 [95% confidence interval 1.82 to 3.44]), prior myocardial infarction (3.99 [2.15 to 7.39]), unstable angina (2.27 [1.69 to 3.04]), chronic renal failure (4.87 [3.13 to 7.58]), atrial fibrillation (2.21 [1.65 to 2.96]), left internal mammary artery to left anterior descending artery graft (0.28 [0.18 to 0.43]), preoperative β-blocker (0.43 [0.28 to 0.67]), ejection fraction (0.71/10% [0.64 to 0.80]), left atrium size (0.88/mm [0.84 to 0.92]), diffuse wall motion abnormalities (2.83 [1.77 to 4.55]), and mitral leaflet restriction (3.85 [2.46 to 5.99]). The model controlled for the performance of annuloplasty, which did not emerge as an independent predictor. Patients undergoing annuloplasty did have less mean late MR than those having CABG alone (p = 0.005). Overall, 57.8% of patients (63 of 109) with follow-up echocardiograms had improvement in grade of MR compared with baseline. In 54 of 95 patients (56.8%), intraoperative transesophageal echocardiography downgraded the degree of MR compared with the preoperative study.

Conclusions

Patients with moderate ischemic MR undergoing CABG had relatively poor long-term survival, with significant differences when stratified according to preoperative characteristics. Performance of mitral annuloplasty reduced the degree of regurgitation but was not a predictor of long-term survival. Intraoperative transesophageal echocardiography frequently downgraded the degree of MR.

Section snippets

Study group

Ethics approval for this study was obtained from the Institutional Review Board. Between 1991 and 2001, 8,442 patients at our hospital underwent first-time CABG as determined by a prospectively collected institutional database of cardiac surgical procedures. By matching patients in this group with our echocardiographic database, 3,641 patients were found with a total of 7,799 echocardiography studies performed at this institution. Of these, 325 had moderate (3+) mitral regurgitation on a

Population Characteristics

Baseline demographic, comorbid, and operative data are detailed in Table 1. Overall, the mean age was 71.1 years, and there was a high frequency of diabetes, previous myocardial infarction, unstable angina, and other comorbidities in the study population. At operation, most patients (88.0%) had three or more distal targets grafted, and 31 patients had mitral annuloplasty performed. Cardiopulmonary bypass times were longer with concomitant annuloplasty than CABG alone (161 versus 106 minutes, p

Results of Surgery for Moderate IMR

In this study, we examined a homogeneous group limited to 3+ IMR on preoperative echocardiogram. Patients presented with a high level of acuity, comorbidity, and risk. Operative mortality was 5.2% for the whole group. Reports in the literature have cited operative mortality between 1.8% and 4.5% for CABG with mild to moderate degrees of IMR [9, 10, 11]. Unadjusted in-hospital complication rates were worse with concomitant annuloplasty, consistent with some, but not all, contemporary studies [12

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Cited by (102)

10-Year Results of Mitral Repair and Coronary Bypass for Ischemic Regurgitation: A Randomized Trial
2022, Annals of Thoracic Surgery
The decision to treat moderate ischemic mitral regurgitation (IMR) at the time of coronary artery bypass surgery (CABG) remains controversial. We previously conducted a prospective randomized trial that showed a benefit of adding restricted annuloplasty to bypass surgery (CABG-Ring group) in terms of IMR grade, New York Heart Association classification, and left ventricle reverse remodeling. Here, we present the long-term (>10 years) follow-up data from this randomized trial.
The original trial arms accounted for 54 patients in the CABG-alone and 48 in the CABG-Ring group; patients were re-contacted for follow-up to obtain relevant clinical and echocardiographic information.
The mean follow-up was 160.4 ± 45.5 months. Survival probabilities in the CABG-alone and CABG-Ring groups were 96% vs 93% at 3 years, 85% vs 89% at 6 years, 79% vs 85% at 9 years, 77% vs 83% at 12 years, and 72% vs 80% at 15 years, respectively (P = .18) Freedom from at least moderate IMR or reintervention at last follow-up was also higher in the CABG-Ring group (P < .001). Compared with the CABG-alone group, the CABG-Ring group had a higher degree of left ventricular reverse remodeling (54.7 ± 6.9 mm vs 51.6 ± 6 mm, respectively; P = .03), lower New York Heart Association class (P < .001), and a lower rate of rehospitalization (P = .002).
Long-term follow-up data from our randomized trial further support the utility of performing restricted annuloplasty at the time of CABG to prevent further progression of IMR, mitral reintervention, and left ventricle remodeling. Untreated IMR was associated with significantly higher New York Heart Association class and rehospitalization.
Cost-effectiveness of coronary artery bypass grafting plus mitral valve repair versus coronary artery bypass grafting alone for moderate ischemic mitral regurgitation
2020, Journal of Thoracic and Cardiovascular Surgery
The Cardiothoracic Surgical Trials Network reported that left ventricular reverse remodeling at 2 years did not differ between patients with moderate ischemic mitral regurgitation randomized to coronary artery bypass grafting plus mitral valve repair (n = 150) or coronary artery bypass grafting alone (n = 151). To address health resource use implications, we compared costs and quality-adjusted survival.
We used individual patient data from the Cardiothoracic Surgical Trials Network trial on survival, hospitalizations, quality of life, and US hospitalization costs to estimate cumulative costs and quality-adjusted life years. A microsimulation model was developed to extrapolate to 10 years. Bootstrap and deterministic sensitivity analyses were performed to address uncertainty.
In-hospital costs were $59,745 for coronary artery bypass grafting plus mitral valve repair versus $51,326 for coronary artery bypass grafting alone (difference $8419; 95% uncertainty interval, 2259-18,757). Two-year costs were $81,263 versus $67,341 (difference 13,922 [2370 to 28,888]), and quality-adjusted life years were 1.35 versus 1.30 (difference 0.05; −0.04 to 0.14), resulting in an incremental cost-effectiveness ratio of $308,343/quality-adjusted life year for coronary artery bypass grafting plus mitral valve repair. At 10 years, its costs remained higher ($107,733 vs $88,583, difference 19,150 [−3866 to 56,826]) and quality-adjusted life years showed no difference (−0.92 to 0.87), with 5.08 versus 5.08. The likelihood that coronary artery bypass grafting plus mitral valve repair would be considered cost-effective at 10 years based on a cost-effectiveness threshold of $100K/quality-adjusted life year did not exceed 37%. Only when this procedure reduces the death rate by a relative 5% will the incremental cost-effectiveness ratio fall below $100K/quality-adjusted life year.
The addition of mitral valve repair to coronary artery bypass grafting for patients with moderate ischemic mitral regurgitation is unlikely to be cost-effective. Only if late mortality benefits can be demonstrated will it meet commonly used cost-effectiveness criteria.
Mitral valve surgery and coronary artery bypass grafting for moderate-to-severe ischemic mitral regurgitation: Meta-analysis of clinical and echocardiographic outcomes
2017, Journal of Thoracic and Cardiovascular Surgery
This meta-analysis was conducted to compare clinical and echocardiographic outcomes following isolated coronary artery bypass grafting (CABG) versus CABG and mitral valve (MV) surgery in patients with moderate-to-severe ischemic mitral regurgitation (IMR).
Seven databases were systematically searched to identify relevant studies. For eligibility, studies were required to report on the primary endpoint of perioperative or late mortality. Data were analyzed according to predefined clinical endpoints.
Four randomized controlled trials (RCTs) (n = 505) and 15 observational studies (OS) (n = 3785) met the criteria for inclusion. Compared with isolated CABG, concomitant CABG and MV surgery was not associated with increased perioperative mortality (RCTs: relative risk [RR] 0.89, 95% confidence interval [CI], 0.26-3.02; OS: RR 1.40, 95% CI, 0.88-2.23). CABG and MV surgery was associated with significantly lower incidence of moderate-to-severe MR at follow-up (RCTs: RR 0.16, 95% CI, 0.04-0.75; OS: RR 0.20, 95% CI, 0.09-0.48). Late mortality was similar between the surgical approaches in RCTs (hazard ratio [HR] 1.20, 95% CI, 0.57-2.53) and OS (HR 0.99, 95% CI, 0.81-1.21). There were no significant differences in echocardiographic outcomes. These results remained consistent in subgroup analyses restricted to patients with strictly moderate IMR.
In patients with moderate-to-severe IMR, the addition of MV surgery to CABG was not associated with increased perioperative mortality. Although concomitant MV surgery reduced recurrence of moderate-to-severe MR at follow-up, this was not associated with a reduction in late mortality. Larger trials with longer follow-up duration are required to further assess long-term survival and freedom from reintervention.
Meta-Analysis of Usefulness of Concomitant Mitral Valve Repair or Replacement for Moderate Ischemic Mitral Regurgitation With Coronary Artery Bypass Grafting
2017, American Journal of Cardiology
Moderate ischemic mitral regurgitation (MR) is often present in patients undergoing coronary artery bypass grafting (CABG). However, the clinical benefit of repairing moderate MR during CABG is unproven. We searched multiple databases to identify original studies comparing isolated CABG versus combined CABG and MR surgery (mitral valve surgery with coronary artery bypass grafting [MVCABG]); survival (either early or midterm) was the primary end point. Risk ratio (RR) or standardize mean difference was selected as the effect estimates; survival was compared by pooling hazard ratios. All results are presented with 95% CIs; p <0.05 is statistically significant. Eleven studies (7 retrospective and 4 randomized controlled trials; 547 MVCABG and 900 CABG patients) were included in our meta-analysis. Concomitant mitral valve repair significantly prolonged surgical duration (p <0.01). Early mortality (MVCABG 6.9% and CABG 6%) was comparable (RR 1.3 [0.9 to 1.8]; p = 0.11). At follow-up, the MVCABG patients had similar New York Heart Association class (standardize mean difference −0.73 (−1.64 to 0.18; p = 0.11). However, patients who underwent concomitant mitral valve surgery had less MR at follow-up (recurrent significant MR, RR 0.37 [0.22 to 0.62]; p = 0.001; mean MR grade, mean difference = 0.39 [0.26 to 0.59]; p <0.001). Midterm survival rate (mean follow-up 5 years) was comparable in both groups (hazard ratio for mortality in the MVCABG cohort 1.1 [0.9 to 1.3]; p = 0.38). In conclusion, concomitant repair of moderate ischemic MR leads to improved mitral valve competence at follow-up; however, this was not translated into any functional or survival benefit for adding valve repair to CABG for these patients at 5 years of follow-up.
Short- and Medium-Term Effects of Combined Mitral Valve Surgery and Coronary Artery Bypass Grafting Versus Coronary Artery Bypass Grafting Alone for Patients with Moderate Ischemic Mitral Regurgitation: A Meta-Analysis
2016, Journal of Cardiothoracic and Vascular Anesthesia
To investigate the short- and medium-term effects of combined mitral valve surgery (MVS) and coronary artery bypass grafting (CABG) versus CABG alone for patients with moderate ischemic mitral regurgitation (IMR).
Meta-analysis of 4 randomized controlled trials (RCTs) and 5 observational studies.
Hospitals that perform cardiac surgery.
The study included 1,256 cardiac surgery patients from 4 RCTs and 5 observational studies.
None.
Four RCTs and 5 observational studies were included in this meta-analysis. Concomitant MVS significantly reduced the residual rate of postoperative IMR (moderate or severe) (RCTs: OR –0.32, 95% confidence interval [CI] –0.58 to –0.07, p = 0.01; observational studies: OR –0.23, 95% CI –0.34 to –0.12, p<0.0001) and the proportion of surviving patients with New York Heart Association class III or IV (RCTs: OR 0.45, 95% CI 0.31-1.8, p = 0.008), but did not improve early mortality (RCTs: OR 0.91, 95% CI 0.30-2.74, p = 0.87; observational studies: OR 1.63, 95% CI 0.88-3.05, p = 0.12) or medium-term mortality (RCTs: OR 0.89, 95% CI 0.46-1.74, p = 0.73; observational studies: OR 0.94, 95% CI 0.65-1.37, p = 0.48) compared with CABG alone. Moreover, adding the mitral valve procedure did not significantly increase the risk of stroke (RCTs: OR 2.27, 95% CI 0.73-7.08, p = 0.16; observational studies: OR 0.55, 95% CI 0.10-3.06, p = 0.50).
The potential benefits of combined MVS and CABG could outweigh its risks for patients with moderate IMR.
Comparative study of coronary artery bypass grafting combined with off-pump mitral valvuloplasty versus coronary artery bypass grafting alone in patients with moderate ischemic mitral regurgitation
2023, Perfusion (United Kingdom)

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Original articleCardiovascularLong-Term Survival After Surgical Revascularization for Moderate Ischemic Mitral Regurgitation

Background

Methods

Results

Conclusions

Section snippets

Study group

Population Characteristics

Results of Surgery for Moderate IMR

Am J Cardiol

Am J Cardiol

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

Lancet

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

Ann Thorac Surg

Ann Thorac Surg

J Thorac Cardiovasc Surg

Ann Thorac Surg

Ann Thorac Surg

Ann Thorac Surg

Chest

Original article
Cardiovascular
Long-Term Survival After Surgical Revascularization for Moderate Ischemic Mitral Regurgitation