Early results of aortic valve replacement with or without concomitant coronary artery bypass grafting

Effect of Concomitant Coronary Artery Bypass Grafting on Outcomes of Ascending Aorta Replacement

BACKGROUND

Ascending aorta replacement can be performed safely in high-volume centers. What remains unknown is whether concomitant coronary revascularization with bypass grafting affects postoperative outcomes.

METHODS

This study retrospectively reviewed a prospectively maintained institutional database for patients who underwent ascending aorta replacement (AAR) during the period from 1997 to 2018. Patients were stratified into AAR alone (AAR) vs AAR and coronary artery bypass graft (AAR with CABG), further categorized as 1 or more than 1 CABG. Aortic dissection and root replacement cases were excluded. The primary end point consisted of major adverse events (MAE), including operative mortality, perioperative myocardial infarction, stroke, need for tracheostomy, and need for dialysis. Secondary end points were operative mortality, each MAE component, and late survival.

RESULTS

A total of 951 patients were included in the analysis; 725 (76.2%) underwent isolated AAR, and 226 (23.8%) underwent AAR with CABG. Operative mortality was similar across the 2 groups (1.8% for AAR with CABG and 0.8% for AAR; P = .40). The unadjusted incidence of MAE was higher in the AAR with CABG group (5.8% vs 1.9%; P = .005).). On multivariable analysis, the performance of 1 CABG (odds ratio [OR], 1.90; 95% confidence interval [CI], 0.67 to 5.33; P = .23) and more than 1 CABG (OR, 2.65; 95% CI, 0.93 to 7.53; P = .07) was not associated with higher rates of MAE. Preoperative pulmonary dysfunction (OR, 2.51; 95% CI, 1.07 to 5.85; P = .03) was the only independent predictor of MAE.

CONCLUSIONS

In patients undergoing concomitant CABG with AAR, the performance of concomitant CABG is not associated with an increased risk of MAE.

The effect of coronary artery disease defined by quantitative coronary angiography and SYNTAX score upon outcome after transcatheter aortic valve implantation (TAVI) using the Edwards bioprosthesis

AIMS

We sought to evaluate the effects of significant coronary artery disease (CAD) upon outcome after transcatheter aortic valve implantation (TAVI).

METHODS AND RESULTS

We performed a retrospective study of 271 consecutive patients undergoing TAVI using either the Edwards SAPIEN or Edwards SAPIEN XT valve. Pre-procedural coronary angiograms were analysed by quantitative coronary angiography (defining significant CAD as a stenosis of ≥70% or ≥50% if in the left main stem or a vein graft). Ninety-three out of 271 patients had significant CAD. There was no difference in mortality at 30 days or 12 months between the two groups (6.7% vs. 7.5% and 21.5% vs. 23.7%; log-rank p=0.805). A secondary analysis using the SYNTAX algorithm of coronary anatomy complexity was performed on 189 patients. Those in the high SYNTAX score (>33) group had higher mortality at 30 days and 12 months (14.3% and 57.1%) than the low (5.2% and 23.3%) and intermediate-risk groups (11.1% and 22.2%; log-rank p=0.007). ROC analysis identified a SYNTAX score of >9 at the time of TAVI as the optimal cut-off, with an independent association with mortality (HR 1.95 [95% CI: 1.21-3.13]; p=0.006). Patients with a SYNTAX score >9 had greater 30-day, 12-month and overall mortalities than those with a SYNTAX score <9 (3.7% vs. 11.3% and 20.7% vs. 34.3%; log-rank p=0.005).

CONCLUSIONS

Significant CAD, as defined using "real-world" QCA margins, did not have a significant effect upon mortality after TAVI for severe aortic stenosis. However, higher-risk SYNTAX groups, including those with a score >9, had increased mortality.

Effect of coronary artery disease extent on contemporary outcomes of combined aortic valve replacement and coronary artery bypass graft surgery

BACKGROUND

Concomitant aortic valve replacement (AVR) and coronary artery bypass graft surgery (CABG) is a common procedure. Whether the extent of coronary artery disease (CAD) influences outcomes of AVR plus CABG is unknown.

METHODS

All AVR plus CABG cases from 2008 to 2010 were extracted from the California CABG Outcomes Reporting Program database. Patients with left main coronary artery stenosis greater than 50% or at least three diseased vessels were defined as having extensive CAD, and patients with one or two diseased coronary vessels were defined as having less extensive CAD. Multivariable logistic regression models were developed for predicting major postoperative complications and 30-day mortality. A Cox proportional hazards model was developed to predict the risk of 1-year mortality.

RESULTS

Between 2008 and 2010, 6,151 AVR plus CABG were performed in California. Compared with patients with one- or two-vessel CAD, patients with extensive CAD undergoing AVR plus CABG were on average older, more often male, had greater prevalence of multiple comorbidities, and underwent more urgent or emergent operations (all p < 0.05). After adjusting for baseline risk factors, AVR plus CABG with extensive CAD was associated with significantly increased risk of major postoperative complications (adjusted odds ratio, 1.24; 95% confidence interval, 1.10 to 1.40; p = 0.001) but not operative mortality (adjusted odds ratio, 1.00; 95% confidence interval, 0.77 to 1.29; p = 0.978). A Cox proportional hazards model showed that age and other medical comorbidities, but not extensive CAD, were significant risk factors for 1-year mortality.

CONCLUSIONS

Compared with AVR plus CABG for one- or two-vessel CAD, AVR plus CABG for left main or three or more vessel CAD had higher observed and risk-adjusted rates of postoperative complications but not operative or 1-year mortality.

Coronary artery disease and outcomes of aortic valve replacement for severe aortic stenosis

OBJECTIVES

The study sought to contrast risk profiles and compare outcomes of patients with severe aortic stenosis (AS) and coronary artery disease (CAD) who underwent aortic valve replacement (AVR) and coronary artery bypass grafting (AS+CABG) with those of patients with isolated AS who underwent AVR alone.

BACKGROUND

In patients with severe AS, CAD is often an incidental finding with underappreciated survival implications.

METHODS

From October 1991 to July 2010, 2,286 patients underwent AVR+CABG and 1,637 AVR alone. A propensity score was developed and used for matched comparisons of outcomes (1,082 patient pairs). Analyses of long-term mortality were performed for each group, then combined to identify common and unique risk factors.

RESULTS

Patients with AS+CAD versus isolated AS were older, more symptomatic, and more likely to be hypertensive, and had lower ejection fraction and greater arteriosclerotic burden but less severe AS. Hospital morbidity and long-term survival were poorer (43% vs. 59% at 10 years). Both groups shared many mortality risk factors; however, early risk among AS+CAD patients reflected effects of CAD; late risk reflected diastolic left ventricular dysfunction expressed as ventricular hypertrophy and left atrial enlargement. Patients with isolated AS and few comorbidities had the best outcome, those with CAD without myocardial damage had intermediate outcome equivalent to propensity-matched isolated AS patients, and those with CAD, myocardial damage, and advanced comorbidities had the worst outcome.

CONCLUSIONS

Cardiovascular risk factors and comorbidities must be considered in managing patients with severe AS. Patients with severe AS and CAD risk factors should undergo early diagnostics and AVR+CABG before ischemic myocardial damage occurs.

Impact of Coronary Disease after Aortic Valve Replacement

Left ventricular dimensions tend to reduce after aortic valve replacement in patients with aortic stenosis. Whether concomitant coronary artery disease has an influence on postoperative ventricular dimensions has not been evaluated. Between 1998 and 2002, 112 patients underwent aortic valve replacement for aortic stenosis; 68 had isolated aortic valve replacement, and 44 had combined coronary artery bypass grafting. Left ventricular dimensions were assessed by echocardiography preoperatively and at 3 and 12 months postoperatively. Transvalvular mean gradient, left ventricular end-diastolic diameter, and left ventricular mass index decreased significantly postoperatively, while left ventricular ejection fraction improved. Preoperative left ventricular dimensions in patients with isolated aortic stenosis were worse than in those with aortic stenosis and coronary artery disease. After aortic valve replacement with coronary artery bypass, left ventricular mass index regression was less than that after valve replacement alone, and there was no improvement in ejection fraction. This suggests that coronary artery disease has a negative impact on postoperative myocardial recovery.

Effect of pexelizumab in coronary artery bypass graft surgery with extended aortic cross-clamp time

BACKGROUND

Prolonged cross-clamp time during cardiac surgery increases the risk of postoperative mortality and myocardial injury. This subanalysis from the pexelizumab for reduction of infarction and mortality in coronary artery bypass grafting surgery (PRIMO-CABG) trial, a phase III double-blind, placebo-controlled study of 3,099 patients undergoing on-pump coronary artery bypass graft surgery with or without valve surgery, assessed the impact of pexelizumab, an investigational C5 complement inhibitor, on postoperative outcomes after prolonged aortic cross-clamp time.

METHODS

The composite endpoint of death or myocardial infarction through postoperative day 30 and death alone through days 30, 90, and 180 were examined in subpopulations of patients across different cross-clamp times.

RESULTS

After prolonged cross-clamping (> or = 90 minutes), death, or myocardial infarction through day 30 and death through days 30, 90, and 180 were significantly increased in the intent-to-treat population and were even higher in patients with two or more prespecified risk factors, compared with all patients cross-clamped less than 90 minutes. Pexelizumab significantly reduced the incidence of death or myocardial infarction through day 30, and significantly reduced the incidence of mortality through day 180, in patients with two or more risk factors that required prolonged cross-clamp time. Pexelizumab also significantly reduced perioperative myocardial injury in all patients requiring prolonged cross-clamp time.

CONCLUSIONS

In this retrospective, subgroup analysis, pexelizumab reduced postoperative morbidity and myocardial injury in patients with multiple risk factors who underwent prolonged cross-clamp time during coronary artery bypass surgery. The clinical benefit of pexelizumab may be related to the effect of complement inhibition in the presence of potential ischemic-reperfusion injury associated with prolonged aortic cross-clamp time.

Papillary muscle repair surgery in ischemic mitral valve patients

BACKGROUND

Ischemic mitral regurgitation (MR), when ischemia/infarction has resulted in fibrotic degeneration and elongation of papillary muscles, carries a high risk for the patient and a technical challenge for the surgeon. We have developed a papillary-shortening plasty for this specific pathology.

METHODS

Papillary muscle repair was performed in 88 patients (7.2%) where degenerated and fibrotic elongated papillary muscles were found, which resulted in a prolapse of one or more parts of the mitral valve leaflets (MR III-IV). All patients had a papillary muscle-shortening plasty using a pericardium pledged-reinforced polytetrafluoroethylene suture and a ring annuloplasty. Because the cause of regurgitation in this specific group of patients was ischemic, concomitant coronary bypass grafting was required in all patients, with 2.2 grafts/patient.

RESULTS

There were five hospital deaths (5.7%). Postoperative mitral valve function was satisfactory in all patients: no residual mitral regurgitation (MR 0) was found in 80 patients (90.9%), mild regurgitation (MR I) in 5 patients (5.7%), and moderate regurgitation (MR I-II) was observed in 3 patients (3.4%). Within a short mean follow-up period of 18.6 months (3 to 40 months), there was one late death (1.2%). The actuarial freedom from reoperation and thromboembolic complications was 100%, but there were two anticoagulation-induced gastric bleeding complications (2.3%). All patients were in New York Heart Association functional class I or II at the time of follow-up.

CONCLUSIONS

Our data show that careful assessment of papillary muscle pathology is mandatory, and that a papillary muscle-shortening plasty is a simple but valuable surgical tool to repair the mitral valve in this specific group of high-risk patients with ischemic mitral regurgitation.

Ten-year trends in heart valve replacement operations

BACKGROUND

There has been increasing concern in recent years about the quality and cost of heart valvular replacement procedures. The purpose of this study is to examine the profile of patients undergoing valvular operations during the past decade, and to look at trends in outcome and resource utilization over that period.

METHODS

Clinical and procedural data of 2,972 patients undergoing heart valve replacement at Emory University Hospitals between 1988 and 1997 were recorded prospectively on standardized forms by trained medical personnel and entered into a computerized database.

RESULTS

There were 1,802 patients undergoing aortic valve replacement (AVR), 966 undergoing mitral valve replacement (MVR), and 204 undergoing combined aortic and mitral valve procedures (AVR + MVR). No patients were excluded. There was a statistically significant trend for patients undergoing AVR, MVR, or AVR + MVR over time to be older and sicker by multiple criteria. Nonetheless, procedural outcome and inhospital mortality for patients undergoing AVR remained unchanged. Cost and length of stay increased from 1988 to 1992 when a concerted effort to decrease resource utilization began. Between 1992 and 1997 for AVR, length of stay decreased from 13.4 to 8.0 days and cost from $37,047 to $21,856. Similarly, between 1992 and 1997 for MVR, length of stay decreased from 15.6 to 8.1 days and cost from $45,072 to $21,747. The net result over the time period from 1988 to 1997 was an average decline in the cost of operation of $785 a year, adjusted for other factors.

CONCLUSIONS

This study reveals that outcome of valvular replacement during the period from 1988 to 1997 has remained constant despite the patients becoming older and sicker during the same period. This constant outcome has been accomplished, but length of stay has decreased significantly. Hospital costs increased during the first years of the study period, but then decreased to levels in 1997 that were equal to or significantly less than 1988 levels.

The natural history and rate of progression of aortic stenosis

One of the challenges in clinical cardiology is to determine the optimal time of valve replacement surgery in patients with aortic stenosis. To meet this challenge, one requires an accurate knowledge of the natural history and rate of progression of the disease. This review will summarize the natural history of aortic stenosis in terms of symptoms, mortality, and stenosis progression.

Long-term relative survival after primary heart valve replacement

OBJECTIVE

Determination of the optimal timing of primary heart valve replacement is an important issue. The present paper provides a synopsis over early and late survival after primary heart valve replacement, including an evaluation of the excess mortality among heart valve replacement patients compared with the general population.

METHODS

Survival was analyzed in 2365 patients (1568 without and 797 with concomitant coronary artery bypass grafting (CABG)) who underwent their first heart valve replacement. Observed survival was related to that expected among persons from the general Swedish population stratified by age, sex, and 5-year calendar period, to calculate the relative survival and estimate the disease-specific survival.

RESULTS

Early mortality (death within 30 days after surgery) was 5.9% after aortic valve replacement, 10.4% after mitral valve replacement and 10.6% after combined aortic and mitral valve replacement. Relative survival rates (excluding early deaths) were 84% 10 years after aortic, 68.5% after mitral and 80.9% after both aortic and mitral valve replacement. A multivariate model based on observed survival rates was produced for each group, using the Cox proportional hazards model. Concomitant CABG, advanced New York Heart Association (NYHA) class, preoperative atrial fibrillation, pure aortic regurgitation and higher age increased the late observed survival after aortic valve replacement. NYHA class was the only factor independently related to observed late deaths after mitral valve replacement, and mitral insufficiency the only corresponding factor after both aortic and mitral valve surgery.

CONCLUSION

The use of relative survival rates tended to modify the difference between subgroups compared with observed survival rates. Relative survival rates reduced the effect of concomitant CABG on survival, but enhanced for example the effect of aortic regurgitation. In patients > or = 70 years of age and patients submitted to aortic or mitral valve replacement with mild or no symptoms, the survival rate was similar for many years to that in the Swedish population at large.

Determinants of early and late results of combined valve operations and coronary artery bypass grafting

BACKGROUND

Factors determining the outcome of operative correction of valvular abnormalities combined with coronary artery bypass grafting are still incompletely defined.

METHODS

Determinants of early and late (more than 90 days) deaths and event-free survival were studied for combined valve operations and coronary artery bypass grafting in 741 patients using multivariate analysis.

RESULTS

Ninety-day survival probability was 89% (95% confidence interval, 87% to 92%). Preoperative risk factors for early death were age, female sex, renal failure, New York Heart Association class IV or V, and mitral insufficiency. The operative risk factor was the duration of aortic cross-clamping. Five- and 10-year survival probabilities were 74% (95% confidence interval, 71% to 78%) and 43% (95% confidence interval, 36% to 50%), respectively. Preoperative risk factors for late death were age, preoperative renal failure, New York Heart Association class IV or V, vessel disease, and nonsinus rhythm. Five- and 10-year event-free survival probabilities were 57% (95% confidence interval, 53% to 61%) and 23% (95% confidence interval, 17% to 28%), respectively. Preoperative risk factors for non-event-free survival were age, female sex, reduced left ventricular function, mitral regurgitation, and pacemaker rhythm.

CONCLUSION

The demographic factors of age and female sex; the comorbid condition of renal failure; the cardiac conditions of advanced New York Heart Association class, left ventricular function, mitral regurgitation, vessel disease, and cardiac rhythm; and the operative condition of ischemia time are the most important predictors of clinical outcome after combined valve operations and coronary artery bypass grafting.