Long-term outcomes of surgical aortic valve replacement in patients receiving chronic dialysis.

BACKGROUND: Surgical aortic valve replacement (SAVR) has been the standard treatment for symptomatic severe aortic stenosis, which is common among patients receiving long-term dialysis. The aim of this study was to report the long-term outcomes of SAVR in patients receiving chronic dialysis and to identify independent risk factors for early and late mortality. METHODS: Every consecutive patient with SAVR with or without concomitant cardiac procedures in British Columbia between January 2000 and December 2015 was identified from the provincial cardiac registry. The Kaplan-Meier method was used to estimate survival. Univariate and multivariable models were conducted to determine independent risk factors for short-term mortality and reduced long-term survival. RESULTS: Between 2000 and 2015, 654 patients receiving dialysis underwent SAVR with or without concomitant procedures. The mean follow-up was 2.3 (standard deviation 2.4) years (median 2.5 yr). The overall 30-day mortality was 12.8%. The 5-year and 10-year survival rates were 45.6% and 23.5%, respectively. Twelve patients (1.8%) had redo aortic valve surgery. There was no difference in 30-day mortality or long-term survival between 2 age groups (> 65 yr v. ≤ 65 yr). Anemia and cardiopulmonary bypass (CPB) were independent risk factors for both longer hospital stay and reduced long-term survival. The impact of CPB pump time on mortality occurred mainly within the first 30 days after surgery. When CPB pump time extended beyond 170 minutes, there was a significant increase in 30-day mortality with further prolongation of CPB pump time, and the relationship between 30-day mortality and CPB pump time became approximately linear. CONCLUSION: Patients receiving dialysis have poor long-term survival with a very low rate of redo aortic valve surgery following SAVR with or without concomitant procedures. Older age (> 65 yr) is not an independent risk factor for either 30-day mortality or reduced long-term survival. Using alternative strategies to limit CPB pump time is an important way to reduce 30-day mortality.

Eight-year outcomes of aortic valve replacement with the Carpentier-Edwards PERIMOUNT Magna Ease valve.

INTRODUCTION: The Carpentier-Edwards PERIMOUNT Magna Ease valve is a third-generation bioprosthesis for aortic valve replacement (AVR). This is a postapproval study reporting on its 8-year outcomes. METHODS: Adults undergoing AVR with the Magna Ease valve between October 2007 and December 2012 were enrolled for this prospective, nonrandomized, single-arm, and multicenter study. Assessments occurred preoperatively, at hospital discharge, 6 months, 1 year, and annually thereafter for up to 8 years. Outcomes included safety endpoints, hemodynamic performance, and New York Heart Association (NYHA) functional class. RESULTS: Of the 258 study patients, 67.5% were in NYHA Class I or II, and 32.5% were in NYHA Class III or IV at baseline. Concomitant procedures were performed in 44.2%. Total follow-up was 1597.6 patient-years, and median follow-up was 7 years (interquartile range: 5.5-8.0 years). Eight years following AVR, the functional class remained improved from baseline with 93.9% in NYHA Class I/II and 6.1% in NYHA Class III; 38 deaths had occurred, 8 of which were valve related; freedom from all-cause mortality was 80.7% (95% confidence intervals: 74.9, 86.4); freedom from valve-related mortality was 95.8% (92.8, 98.8); freedom from reintervention, explant, major bleeding events, and structural valve deterioration was 89.8% (85.1, 94.6), 94.8% (91.7, 97.9), 85.1% (80.0, 90.1), and 90.1% (84.7, 95.4), respectively; effective orifice area was 1.5 ± 0.5 cm2 , the mean gradient was 14.8 ± 8.3 mmHg, and 88.6% of patients had no or trivial aortic regurgitation. CONCLUSIONS: This study demonstrated satisfactory safety and sustained hemodynamic and functional improvements at 8 years following AVR with the Magna Ease valve.

Surgical Versus Percutaneous Coronary Revascularization in Patients With Diabetes and Acute Coronary Syndromes.

BACKGROUND: Randomized trial data support the superiority of coronary artery bypass grafting (CABG) surgery over percutaneous coronary intervention (PCI) in diabetic patients with multivessel coronary artery disease (MV-CAD). However, whether this benefit is seen in a real-world population among subjects with stable ischemic heart disease (SIHD) and acute coronary syndromes (ACS) is unknown. OBJECTIVES: The main objective of this study was to assess the generalizability of the FREEDOM (Future REvascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multi-vessel Disease) trial in real-world practice among patients with diabetes mellitus and MV-CAD in residents of British Columbia, Canada. Additionally, the study evaluated the impact of mode of revascularization (CABG vs. PCI with drug-eluting stents) in diabetic patients with ACS and MV-CAD. METHODS: In a large population-based database from British Columbia, this study evaluated major cardiovascular outcomes in all diabetic patients who underwent coronary revascularization between 2007 and 2014 (n = 4,661, 2,947 patients with ACS). The primary endpoint (major adverse cardiac or cerebrovascular events [MACCE]) was a composite of all-cause death, nonfatal myocardial infarction, and nonfatal stroke. The risk of MACCE with CABG or PCI was compared using multivariable adjustment and a propensity score model. RESULTS: At 30-days post-revascularization, for ACS patients the odds ratio for MACCE favored CABG 0.49 (95% confidence interval [CI]: 0.34 to 0.71), whereas among SIHD patients MACCE was not affected by revascularization strategy (odds ratio: 1.46; 95% CI: 0.71 to 3.01; pinteraction <0.01). With a median follow-up of 3.3 years, the late (31-day to 5-year) benefit of CABG over PCI no longer varied by acuity of presentation, with a hazard ratio for MACCE in ACS patients of 0.67 (95% CI: 0.55 to 0.81) and the hazard ratio for SIHD patients of 0.55 (95% CI: 0.40 to 0.74; pinteraction = 0.28). CONCLUSIONS: In diabetic patients with MV-CAD, CABG was associated with a lower rate of long-term MACCE relative to PCI for both ACS and SIHD. A well-powered randomized trial of CABG versus PCI in the ACS population is warranted because these patients have been largely excluded from prior trials.

Long-term Outcomes of Multiple Arterial Coronary Artery Bypass Grafting: A Population-Based Study of Patients in British Columbia, Canada.

Importance: Although the long-term survival advantage of multiple arterial grafting (MAG) vs the standard use of left internal thoracic artery (LITA) supplemented by saphenous vein grafts (LITA+SVG) has been demonstrated in several observational studies, to our knowledge its safety and other long-term clinical benefits in a large, population-based cohort are unknown. Objective: To compare the safety and long-term outcomes of MAG vs LITA+SVG among overall and selected subgroups of patients. Design, Setting, and Participants: In this population-based observational study, we included 20 076 adult patients with triple-vessel or left-main disease who underwent primary isolated coronary artery bypass grafting (MAG, n = 5580; LITA+SVG, n = 14 496) in the province of British Columbia, Canada, from January 2000 to December 2014, with follow-up to December 2015. We performed propensity-score analyses by weighting and matching and multivariable Cox regression to minimize treatment selection bias. Exposures: Multiple arterial grafting or LITA+SVG. Main Outcomes and Measures: Mortality, repeated revascularization, myocardial infarction, heart failure, and stroke. Results: Of 5580 participants who underwent MAG, 586 (11%) were women and the mean (SD) age was 60 (8.7) years. Of 14 496 participants who underwent LITA+SVG, 2803 (19%) were women and the mean (SD) age was 68 (8.9) years. The median (interquartile range) follow-up time was 9.1 (5.1-12.6) years and 8.1 (4.5-11.7) years for the groups receiving MAG and LITA+SVG, respectively. Compared with LITA+SVG, MAG was associated with reduced mortality rates (hazard ratio [HR], 0.79; 95% CI, 0.72-0.87) and repeated revascularization rates (HR, 0.74; 95% CI, 0.66-0.84) in 15-year follow-up and reduced incidences of myocardial infarction (HR, 0.63; 95% CI, 0.47-0.85) and heart failure (HR, 0.79; 95% CI, 0.64-0.98) in 7-year follow-up. The long-term benefits were coherent by all 3 statistical methods and persisted among patient subgroups with diabetes, obesity, moderately impaired ejection fraction, chronic obstructive pulmonary disease, peripheral vascular disease, or renal disease. Multiple arterial grafting was not associated with increased morbidity or mortality rates at 30 days overall or within patient subgroups. Conclusions and Relevance: Compared with LITA+SVG, MAG is associated with reduced mortality, repeated revascularization, myocardial infarction, and heart failure among patients with multivessel disease who are undergoing coronary artery bypass grafting without increased mortality or other adverse events at 30 days. The long-term benefits consistently observed across multiple outcomes and subgroups support the consideration of MAG for a broader spectrum of patients who are undergoing coronary artery bypass grafting in routine practice.

A score to estimate 30-day mortality after intensive care admission after cardiac surgery.

OBJECTIVE: Several risk-scoring systems have been developed to predict surgical mortality and complications in cardiac surgical patients, but none of the current systems include factors related to the intraoperative period. The purpose of this study was to develop a score that incorporates both preoperative and intraoperative factors so that it could be used for patients admitted to a cardiac surgical intensive care unit (ICU) immediately after surgery. METHOD: Preoperative and intraoperative data from 30,350 patients in four hospitals were used to build a multiple logistic regression model estimating 30-day mortality after cardiac surgery. Sixty percent of the patients were used as a derivation group and forty percent as a validation group. RESULTS: Mortality occurred in 2.6% of patients (n = 790). Preoperative factors identified in the model were age, female sex, emergency status, pulmonary hypertension, peripheral vascular disease, renal dysfunction, diabetes, peptic ulcer disease, history of alcohol abuse, and refusal of blood products. Intraoperative risk factors included the need for an intra-aortic balloon pump, ventricular assist device or extracorporeal membrane oxygenation leaving the operating room, presence of any intraoperative complication reported by the surgeon, the use of inotropes, high-dose vasopressors, red blood cell transfusion, and cardiopulmonary bypass time. When used after surgery at ICU admission, the model had C-statistics of 0.86 in both derivation and validation sets to estimate the 30-day mortality. CONCLUSIONS: Preoperative and intraoperative variables can be used on admission to a cardiac surgical ICU to estimate 30-day mortality. The score could be used for risk stratification after cardiac surgery and evaluation of performance of cardiac surgical ICUs.

Determinants of percutaneous coronary intervention vs coronary artery bypass grafting: an interprovincial comparison.

BACKGROUND: Marked variation exists concerning the utilization of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). The objective of this study was to examine differences in predictors of mode of revascularization across 3 provincial jurisdictions. METHODS: All patients who underwent PCI and isolated CABG in British Columbia, Alberta, and Nova Scotia between 1996 and 2007 were considered. Age- and sex-standardized rates of PCI and CABG per 100,000 population and PCI to CABG ratios were calculated by year and province. Logistic regression models were constructed to identify independent predictors of mode of revascularization in each province. RESULTS: A total of 32,190 and 69,409 patients underwent CABG and PCI, respectively, during the study period. Significant increases in the age- and sex-adjusted PCI to CABG ratios were observed in all 3 provinces, but these ratios differed between provinces. Across all 3 jurisdictions, female sex and diagnosis of acute coronary syndrome favoured increased PCI vs CABG, and increased age, left main, or 3-vessel disease occurring before myocardial infarction, and diabetes favoured lower PCI vs CABG. After adjusting for clinical and angiographic factors, there remained a significant variation in choice of PCI vs CABG between the 3 provinces over time. CONCLUSIONS: Significant interprovincial variability in PCI to CABG ratios was observed. Though certain patient-related factors predictive of either PCI or CABG were identified, factors beyond clinical presentation played a role in the choice of revascularization approach.

Seven-year results with the St Jude Medical Silzone mechanical prosthesis.

OBJECTIVE: The Artificial Valve Endocarditis Reduction Trial was stopped on January 21, 2000, due to a higher incidence of paraprosthetic leak in the St Jude Medical Silzone prosthesis compared with the conventional prosthesis. The Artificial Valve Endocarditis Reduction Trial investigators reported the 2-year results in 2002. This retrospective study assessed the influence on thromboembolism and paraprosthetic leak to 7 years. METHODS: A total of 253 patients had 254 operations: 80 aortic valve replacements, 139 mitral valve replacements, and 35 multiple replacements with placement of Silzone prostheses. The mean age was 58.6 years (range 21-84 years, median age 59.8 years), and there were 126 women (49.8%) and 74 concomitant procedures (coronary artery bypass 28.9%). RESULTS: Major paraprosthetic leak (repair, re-replacement, or mortality) occurred in 10 of the original procedures after 30 days (3 aortic valve replacements, 3 mitral valve replacements, 4 multiple replacements). Nine occurrences in 8 patients-5 early (2 years)-were managed. Seven were managed with definitive re-replacement. One was an early nonoperative fatality. There was 1 late fatality after the second late paraprosthetic leak reoperation. One of the 10 procedures occurring after 2 years had mild to moderate aortic valve replacement paraprosthetic leak managed as an incidental re-replacement at the time of correction of supra valvular patch stenosis. One additional occurrence, in addition to the 8 patients (<30 days), was considered a technical error and not related to the Silzone prosthesis and was replaced with a Silzone prosthesis. The linearized rate of paraprosthetic leak within the first 2 years of follow-up was 1.3%/patient-year and after 2 years was 0.4%/patient-year. The linearized occurrence rate for major thromboembolism was 0.42%/patient-year for aortic valve replacement and 1.71%/patient-year for mitral valve replacement. CONCLUSIONS: Paraprosthetic leak with the St Jude Medical Silzone prosthesis was managed both during the early (2years) intervals with re-replacement. Late managed events may be manifestations of earlier occurring paraprosthetic leak. Follow-up echocardiograms should meet standards of care, 6 to 12 months after surgery and at the slightest suspicion of dysfunction. There is no advanced continuing risk of the St Jude Medical Silzone prosthesis.

Early antithrombotic therapy for aortic valve bioprostheses: is there an indication for routine use?

BACKGROUND: Consensus reports over the past 10 years from the United States, Europe, United Kingdom, and Canada have not provided consistent guidelines for antithrombotic therapy of aortic valve bioprostheses for the three-month period after surgery. This study was conducted to determine if antithrombotic therapy was protective against TE with aortic bioprostheses 30 days or less after aortic valve replacement (AVR). METHODS: From 1994 to 2000, 1,372 patients implanted with three currently marketed aortic bioprostheses, Medtronic Mosaic (Medtronic, Inc, Minneapolis, MN) (415 patients), Carpentier-Edwards SAV (462), and Carpentier-Edwards PERIMOUNT (495) (Edwards Lifesciences, Irvine, CA), with a mean age of greater than 70 years were evaluated. Patient populations were comparable, inclusive of concomitant coronary artery bypass grafting (CABG) for the overall populations and for patients greater than 70 years. RESULTS: There were 37 thromboembolic (TE) events: major TE, 14; reversible ischemic neurologic deficit (RIND), 12; and minor TE, 11. There were 4 TE deaths. Multivariate (stepwise logistic regression) analysis revealed no predictive risk factors for overall TE. For the combination of major TE plus RIND there were two predictive risk factors with analysis of 12 risk variables: preoperative cerebrovascular accident (odds ratio [OR] 4.45, 95% confidence interval [CI] 1.17 to 16.87, p = 0.028); and concomitant CABG (OR 3.19, 95% CI 1.16 to 8.76, p = 0.025). Neither anticoagulant nor antiplatelet therapies gave significant protection. CONCLUSIONS: There does not appear to be an indication for routine antithrombotic management. The study supports the potential use of antithrombotic therapy for comorbidities of preoperative cerebrovascular accident and concomitant CABG but not atrial fibrillation, left ventricular dysfunction, or elderly age greater than 70 years. Vascular burden and advanced age are likely contributing factors to these independent predictors. There may still be a need for, or at least consideration of, a randomized trial for AVR with bioprostheses.

The effects of steroids on the occurrence of postoperative atrial fibrillation after coronary artery bypass grafting surgery: a prospective randomized trial.

OBJECTIVE: Atrial fibrillation remains one of the most common postoperative complications of coronary artery bypass grafting. Despite many clinical studies, there is still no consensus regarding the best prevention strategy for atrial arrhythmia. A randomized, double-blind, placebo-controlled trial was conducted to determine the effect of steroids on the occurrence of atrial fibrillation after elective coronary artery bypass grafting. METHODS: Eighty-eight consecutive patients were prospectively entered in this study. No patient had documented or suspected arrhythmias before surgery. Forty-three patients received 1 g of methylprednisolone before surgery and 4 mg of dexamethasone every 6 hours for 1 day after surgery, and 43 patients received only placebo. The primary end point was the overall occurrence of postoperative atrial fibrillation. RESULTS: Postoperative atrial fibrillation occurred in 9 (21%) of the 43 patients in the steroid group, as compared with 22 (51%) of the 43 patients in the placebo group ( P = .003). Minor postoperative complications occurred in 15 steroid patients (35%) and in 6 patients (14%) receiving placebo ( P = .01). Major complications occurred in 4 patients who received steroids (9%) and in 2 patients (5%) who received placebo ( P = .68; for all complications, P = .05). CONCLUSIONS: Prophylactic short-term steroid administration in patients undergoing coronary artery bypass grafting significantly reduced postoperative atrial fibrillation. In this study, there was no significant difference between the steroid group and the placebo group with regard to the length of hospital stay; however, the steroid group had more complications, which may contribute to prolonged hospitalization.

Medtronic mosaic porcine bioprosthesis: investigational center experience to six years.

BACKGROUND AND AIM OF THE STUDY: The findings of this single-center experience with the Medtronic Mosaic porcine bioprosthesis were evaluated to determine the clinical performance of the valve. METHODS: Between 1994 and 2000, a total of 657 patients was implanted with the prosthesis. Aortic valve replacement (AVR) was performed in 415 patients (mean age 70.5+/-10.7 years; range: 26-89 years) and mitral valve replacement (MVR) in 242 patients (mean age 70.5+/-9.5 years; range: 19-86 years). Concomitant coronary artery bypass (CAB) was performed in 51.1% and 46.7% of AVR and MVR patients, respectively. The majority of patients were aged over 70 years (59.8% AVR, 58.7% MVR). RESULTS: Survival at six years was 73.0+/-2.4% after AVR, and 74.0+/-5% after MVR (p = NS). Actual freedom from valve-related mortality at six years was 98+/-1% for AVR and 96+/-1% for MVR; freedom from overall thromboembolism (TE) was 86+/-3% for AVR and 89+/-2% for MVR. After AVR, 42 thromboembolic events occurred in 39 patients (23 minor; 14 major; three reversible ischemic neurologic deficits (RIND); two thrombosis). After AVR, the late TE rate was 2.1% per pt-yr, and the major rate 0.6% per pt-yr (exclusive of thrombosis). The overall TE rate after AVR was 2.9% per pt-yr (major rate 1% per pt-yr). After MVR, 25 events occurred in 24 patients (10 minor; eight major; five RIND; two thrombosis). After MVR, the late TE rate was 2.6% per pt-yr, and the major rate 0.7% per pt-yr (exclusive of thrombosis). The overall TE rate after MVR was 3.5% per pt-yr (major rate 1.1% per pt-yr). There were four cases of structural valve deterioration (SVD) (two each after AVR and MVR). Reoperation was performed in three of four cases of thrombosis, and in two of four cases of SVD. CONCLUSION: The Medtronic Mosaic porcine bioprosthesis is safe and effective. The rate of SVD after six years was low, being zero in the aortic position of patients aged >60 years, and zero also in the mitral position of patients aged <60 years. The incidence of early and late thromboembolism was contributed to by the advanced age of the patient population.

New-onset sustained ventricular tachycardia and fibrillation early after cardiac operations.

BACKGROUND: Malignant ventricular tachyarrhythmia early after cardiac surgery is an uncommon arrhythmic complication but has a negative impact on mortality. The purpose of this study was to evaluate the incidence of new-onset sustained postoperative ventricular tachycardia-ventricular fibrillation and to identify risk factors for the dysrhythmia. METHODS: Demographic, clinical, operative, and postoperative data, including a variable of postoperative ventricular tachycardia, were prospectively obtained from 4748 patients undergoing nonemergency coronary artery bypass graft and(or) valve replacement with no history of sustained ventricular tachycardia or sudden death. A detailed analysis was performed to define the risk factors for the ventricular tachycardia and the prognostic impact of the arrhythmia on 30-day mortality was evaluated. RESULTS: Forty-five patients (0.95%) had sustained ventricular tachycardia or ventricular fibrillation and the initial episode occurred 3.9 +/- 5.2 days (mean +/- standard deviation) after surgery. By multivariate analysis, female sex (odds ratio, 1.982), left ventricular ejection fraction (< 35%: > 50%, 4.771), the presence of pulmonary hypertension (3.066), the presence of systemic hypertension (2.391), and pump time (per 10 minutes, 1.085) were independently associated with the dysrhythmias. Early mortality of patients with the arrhythmia was 28.9%, strikingly higher than that of patients without ventricular tachycardia/ventricular fibrillation (1.9%). CONCLUSIONS: Left ventricular ejection fraction is the strongest risk factor for new-onset postoperative sustained ventricular tachycardia-ventricular fibrillation; female sex, pump time, pulmonary and systemic hypertension are independent predictors of the dysrhythmias; the arrhythmia is associated with increased 30-day mortality after cardiac surgery.

Outcome of mitral valve repair or replacement: a comparison by propensity score analysis.

BACKGROUND: There are no randomized trials comparing outcomes after mitral valve (MV) repair and replacement. Propensity scoring is a powerful tool that has the potential to reduce selection bias in nonrandomized studies. METHODS: From the BC Cardiac Registries, 2,060 patients presented for MV surgery, with or without CABG between 1991 and 2000. We then identified 322 MV repairs who were then matched by propensity score to an equal number of MV replacement patients. We compared survival and freedom from re-operation outcomes using Cox proportional hazards model analysis. Multivariable analysis was then used to compare outcomes in 358 MV repair patients with 352 MV replacement patients who had undergone chordal sparing surgery. RESULTS: The comparison groups generated using propensity scores were well balanced with respect to all collected baseline risk factors. Median follow-up time was 3.4 years. Patients undergoing MV repair had significantly improved survival (RR 0.46; 95% CI, 0.28 to 0.75) but a trend toward more re-operations (RR 2.11; 95% CI, 1.00 to 4.47) compared with patients undergoing replacement. Mitral valve repair patients still had better survival (RR 0.52; 95% CI, 0.32 to 0.85) compared with MV replacement patients who had undergone chordal sparing surgery. CONCLUSIONS: We used propensity score methods to reduce selection bias in a population-based cohort of patients undergoing MV repair/replacement. Repair was associated with better survival, but a trend to increased re-operation.