Outcomes following coronary artery bypass grafting with multiple arterial grafting by pump status in men and women

BACKGROUND

Multiple arterial grafting (MAG) and off-pump surgery are strategies proposed to improve outcomes with coronary artery bypass grafting (CABG). This study was conducted to determine the impact of off-pump surgery on outcomes after CABG with MAG in men and women.

METHODS

This cohort study used population-based data to identify all Ontarians undergoing isolated CABG with MAG between October 2008 and September 2019. The primary outcome was all-cause mortality. Secondary outcomes included major adverse cardiac and cerebrovascular events (MACCE; hospitalization for stroke, myocardial infarction hospitalization or heart failure, or repeat revascularization). Analysis used propensity-score overlap-weighted cause-specific Cox proportional hazard regression.

RESULTS

A total of 2989 women (1188 off-pump, 1801 on-pump) and 16,209 men (6065 off-pump, 10,144 on-pump) underwent MAG with a median follow-up of 5.0 years (interquartile range, 2.7-8.0) years. Compared to the on-pump approach, all-cause mortality was not changed with off-pump status (hazard ratio [HR] in women: 1.25 [95% CI, 0.83-1.88]; in men: 1.08 [95% CI, 0.85-1.37]). In women, the risk of MACCE was significantly higher off-pump (HR, 1.45; 95% CI, 1.04-2.03), with nonsignificantly increased risk observed for all component outcomes.

CONCLUSIONS

In patients undergoing CABG with MAG, this population-based analysis found no association between pump status and survival in either men or women. However, it did suggest that off-pump MAG in women may be associated with an increased risk of MACCE.

Edge-to-edge with partial band mitral valve repair compared to replacement and undersized restrictive annuloplasty for ischemic mitral regurgitation

Objective

Evidence supports replacement over repair for ischemic mitral regurgitation due to improved durability; however, the latter often involves an undersized ring annuloplasty that does not include edge-to-edge approximation. The objective of this study was to evaluate the outcomes of replacement, edge-to-edge leaflet approximation with mild-undersized annuloplasty and undersized ring annuloplasty for ischemic mitral regurgitation.

Methods

This is a single-center retrospective study of patients undergoing mitral surgery for moderate-severe or greater ischemic mitral regurgitation, between 2004 and 2020, with mild-undersized annuloplasty, mitral valve replacement, or undersized restrictive annuloplasty (undersized ring annuloplasty). The primary outcome was all-cause mortality. Secondary outcomes included first recurrence of mitral regurgitation, heart failure hospitalization, and composite of valve-related events (bleeding, thromboembolism, endocarditis, and mitral valve reoperation).

Results

There were 121, 93, and 78 patients in the mitral valve replacement, mild-undersized annuloplasty, and undersized restrictive annuloplasty groups, respectively, with a median follow-up of 3.1, 5.9, and 3.8 years, respectively. Both mitral valve replacement (hazard ratio, 1.87; 95% CI, 1.029-3.415) and undersized restrictive annuloplasty (hazard ratio, 2.73; 95% CI, 1.480-5.061) were associated with worse survival compared with mild-undersized annuloplasty. At 2 years, the rate of mild-moderate mitral regurgitation was greater in the mild-undersized annuloplasty group compared with the mitral valve replacement group (P = .001) but less than in the undersized restrictive annuloplasty group (P = .001). The rate of recurrent moderate or greater mitral regurgitation at 2 years was similar between mild-undersized annuloplasty and mitral valve replacement groups but significantly higher after undersized restrictive annuloplasty (P < .0001). Mitral valve replacement and undersized restrictive annuloplasty were associated with a significant increase in the incidence of first heart failure hospitalization compared with mild-undersized annuloplasty (P < .001 and P = .001, respectively). Mitral valve replacement was associated with an increased incidence of valve-related events compared with mild-undersized annuloplasty (P = .002).

Conclusions

Surgical edge-to-edge approximation in addition to a mild-undersizing annuloplasty offers similar durability compared with replacement, with a lower rate of hospitalization for heart failure, and may confer a survival advantage.

Influence of preoperative frailty on quality of life after cardiac surgery: A systematic review and meta-analysis

BACKGROUND

Frailty has emerged as an important prognostic marker of increased mortality after cardiac surgery, but its association with quality of life (QoL) and patient-centered outcomes is not fully understood. We sought to evaluate the association between frailty and such outcomes in older patients undergoing cardiac surgery.

METHODS

This systematic review included studies evaluating the effect of preoperative frailty on QoL outcomes after cardiac surgery amongst patients 65 years and older. The primary outcome was patient's perceived change in QoL following cardiac surgery. Secondary outcomes included residing in a long-term care facility for 1 year, readmission in the year following the intervention, and discharge destination. Screening, inclusion, data extraction, and quality assessment were performed independently by two reviewers. Meta-analyses based on the random-effects model were conducted. The evidential quality of findings was assessed with the GRADE profiler.

RESULTS

After the identification of 3105 studies, 10 observational studies were included (1580 patients) in the analysis. Two studies reported on the change in QoL following cardiac surgery, which was higher for patients with frailty than for patients without. Preoperative frailty was associated with both hospital readmission (pooled odds ratio [OR] 1.48 [0.80-2.74], low GRADE level) as well as non-home discharge (pooled OR 3.02 [1.57-5.82], moderate GRADE level).

CONCLUSION

While evidence in this field is limited by heterogeneity of frailty assessment and non-randomized data, we demonstrated that baseline frailty may possibly be associated with improved QoL, but with increased readmission as well as discharge to a non-home destination following cardiac surgery. These patient-centered outcomes are important factors when considering interventional options for older patients.

STUDY REGISTRATION

OSF registries (https://osf.io/vm2p8).

Population study of sex-based outcomes after surgical aortic valve replacement

Background

Surgical aortic valve replacement (SAVR) is a key strategy for the treatment of aortic valve disease. However, studies have involved primarily male patients, and whether the benefits of this approach can be extrapolated to female patients is unclear.

Methods

Clinical and administrative datasets for 12,207 patients undergoing isolated SAVR in Ontario from 2008 to 2019 were linked. Male and female patients were balanced using inverse probability treatment weighting. Mortality, endocarditis, and major hemorrhagic and thrombotic events, as well as 2 composite outcomes-major adverse cerebral and cardiovascular events (MACCE) and patient-derived adverse cardiovascular and noncardiovascular events (PACE)-and their component events, were compared in the weighted groups with a stratified log-rank test.

Results

A total of 7485 male patients and 4722 female patients were included in the study. Median follow-up was 5.2 years in both sexes. All-cause mortality did not differ between sexes (hazard ratio [HR] 0.949 [95% confidence interval {CI} 0.851-1.059]). Male sex was associated with an increased risk of new-onset dialysis (HR 0.689 [95% CI 0.488-0.974]). Female sex was associated with a significantly increased risk of both new-onset heart failure (HR 1.211 [95% CI 1.051-1.394], P = 0.0081) and heart failure hospitalization (HR 1.200 [95% CI 1.036-1.390], P = 0.015). No statistically significant differences were seen in any of the other secondary outcomes between sexes.

Conclusions

This population health study demonstrated that survival did not differ between male and female patients undergoing SAVR. Significant sex-related differences were found in the risk of heart failure and new-onset dialysis, but these findings should be considered exploratory and require further study.

Unexplained fever following DeBakey type I aortic dissection repair with woven Dacron grafts

Transient fever is not uncommon postcardiac surgery, usually related to underlying clinical process such as inflammation related to the physiological insult or infection. Here, we present a case series of two patients who underwent repair for type A aortic dissection with Gelweave graft prosthesis who had persistent fevers, leukocytosis, and raised inflammatory markers persisting months after surgery. Both patients were found to have sterile perigraft fluid collections. Comprehensive investigations excluded common causes of postoperative inflammation, as well as rarer causes of fever of unknown origin. The presence of this idiopathic inflammatory state lead to extended hospitalization and resource utilization, prompting need for further characterization of its mechanism and proper management.

Derivation of Patient-Defined Adverse Cardiovascular and Noncardiovascular Events Through a Modified Delphi Process

IMPORTANCE

There is little evidence to support patient-centered outcomes in patients with cardiovascular disease.

OBJECTIVE

To derive patient-defined adverse cardiovascular and noncardiovascular events (PACE) through a consensus-based process.

DESIGN, SETTING, AND PARTICIPANTS

This pan-Canadian, consensus-based, qualitative study used an iterative Delphi method to achieve consensus within a 35-member panel consisting of patients with cardiovascular diseases and their caregivers and clinicians. The process included 4 rounds of online questionnaires, followed by an in-person final consensus meeting. Data analysis was performed in September 2019.

MAIN OUTCOMES AND MEASURES

Defining PACE as a 5-item composite outcome.

RESULTS

Thirty-five potential panelists consented to participate, including 11 clinicians (8 men [73%]) and 24 patients and caregivers (13 men [54%]). Twenty-nine (83%), 28 (80%), 26 (74%), and 23 (66%) of the panelists participated in each of respective the online rounds. A shortlist of 11 patient-defined items was further refined at the in-person meeting, which 20 of the panelists attended. The PACE definition that was decided through the consensus process was a composite of severe stroke necessitating hospitalization for 14 days or longer or inpatient rehabilitation, ventilator dependence, new onset or worsening heart failure, nursing home admission, or new onset dialysis.

CONCLUSIONS AND RELEVANCE

This study defined PACE as a versatile, patient-centered outcome through a consensus process with input from patients, caregivers, and clinicians. Given the paucity of patient-centered outcomes in cardiovascular research, PACE may be considered as a potential outcome after methodological evaluation of its reliability.

Early Midterm Results After Valve Replacement With Contemporary Pericardial Prostheses for Severe Aortic Stenosis

BACKGROUND

Clinical studies have demonstrated improved gradients after aortic valve replacement with the Trifecta (TR) valve (Abbott Cardiovascular, St Paul, MN) as compared with the Carpentier-Edwards Magna Ease (ME) valve (Edwards Lifesciences, Irvine, CA). Clinical benefits of this strategy have not been demonstrated.

METHODS

Patients undergoing aortic valve replacement for severe aortic stenosis with either valve were included. Patients were excluded if they underwent concomitant procedures other than coronary artery bypass grafting. Inverse proportion treatment weighting was used in the analysis. The primary outcome was a composite of cardiac mortality, need for reintervention, and freedom from first congestive heart failure (CHF). Secondary outcomes were all-cause mortality, the composite components, and cumulative CHF admission. Follow-up echocardiograms were assessed in a cohort of patients to assess structural valve degeneration.

RESULTS

There were 331 patients in the TR group and 360 patients in the ME group. The TR group had more women (48% vs 32%, P < .001) with smaller roots (left ventricular outflow tract diameter: TR, 2.11 cm; ME, 2.17 cm; P < .001). After weighting there was no significant difference in the composite measure between groups (P > .05). There was no difference in all-cause mortality (hazard ratio, 0.82; 95% confidence interval, 0.42-1.59; P = .56), and 5-year survival was 91.9% in the ME group and 93.4% in the TR group. There was no difference in cardiac death, reintervention, or first onset of CHF or incidence of structural valve degeneration between groups. There was no difference in the rate of admissions for CHF per 100 patients between the 2 valve types (P = .19).

CONCLUSIONS

Early hemodynamic benefits have not translated into differences in medium-term clinical outcomes between these 2 valves. Long-term follow-up is necessary.

Development of a median sternotomy simulation model for cardiac surgery training

Objective

We sought to develop a simulation model to train resident physicians in the performance of a median sternotomy.

Methods

A modified Delphi consensus process was used with cardiac surgery staff to develop a 20-point checklist for the safe performance of a median sternotomy. Thirteen junior cardiac surgery trainees from across Canada participated in this study to assess the simulation model. Trainees performed the sternotomy before and after reviewing an instructional video. Two senior cardiac surgery resident physicians assessed the participants with the checklist during each session. An entry and exit questionnaire was given to the participants to evaluate the simulation model.

Results

Participants scored higher after the training (14.3 ± 2.0) compared with before training (8.0 ± 3.1) (P < .001). The mean duration of time for participants to complete the sternotomy was shorter before training (188 ± 52 seconds vs 228 ± 58 seconds; P = .003). The checklist interrater reliability was κ = 0.47 (moderate) for before training and κ = 0.37 (fair) for after training. All study participants rated the simulation sessions as very useful or extremely useful.

Conclusions

Using the simulation model, training video, and checklist, trainees were able to improve their skill in performing a median sternotomy. This improvement was associated with longer times to complete all procedure steps. Rater training may further improve interrater reliability. Our median sternotomy checklist and simulation model can be adopted for the technical skills training of future cardiac surgery trainees.

Sex differences in outcomes of heart failure in an ambulatory, population-based cohort from 2009 to 2013

BACKGROUND

Heart failure remains a substantial cause of morbidity and mortality in women. We examined the sex differences in heart failure incidence, mortality and hospital admission in a population-based cohort.

METHODS

All Ontario residents who were diagnosed with heart failure in an ambulatory setting between Apr. 1, 2009, and Mar. 31, 2014, were included in this study. Incident cases of heart failure were captured through physician billing using a validated algorithm. Outcomes were mortality and hospital admission for heart failure within 1 year of the diagnosis. Probability of death and hospital admission were calculated using the Kaplan-Meier method. The hazard of death was assessed using a multivariable Cox proportional hazard model.

RESULTS

A total of 90 707 diagnoses of heart failure were made in an ambulatory setting during the study period (47% women). Women were more likely to be older and more frail, and had different comorbidities than men. The incidence of heart failure decreased during the study period in both sexes. The mortality rate decreased in both sexes, but remained higher in women than men. The female age-standardized mortality rate was 89 (95% confidence interval [CI] 80-100) per 1000 in 2009 and 85 (95% CI 75-95) in 2013, versus male age-standardized mortality rates of 88 (95% CI 80-97) in 2009 and 83 (95% CI 75-91) in 2013. Conversely, the rates of incident heart failure hospital admissions after heart failure diagnosis decreased in men and increased in women.

INTERPRETATION

Despite decreases in overall heart failure incidence and mortality in ambulatory patients, mortality rates remain higher in women than in men, and rates of hospital admission for heart failure increased in women and declined in men. Further studies should focus on sex differences in health-seeking behaviour, medical therapy and response to therapy to provide guidance for personalized care.

Developing a Strategy for the Improvement in Patient Experience in a Canadian Academic Department of Surgery

Patient experience (PE) is recognized as a key component in the quality of health-care delivery. Public reporting of hospital, division, and physician-specific PE results has added to the momentum of adopting strategies to augment this metric of care. The Ottawa Hospital embarked on a journey to improve PE as a pillar of its quality improvement plan. This article demonstrates the efforts of a single surgery department from one large urban center to improve in-hospital PE in the rapidly changing environment of medicine and surgery. A multidisciplinary group within the department and a focus group of previous surgical inpatients were organized to address immediate challenges related to inpatient PE issues. We identified concrete strategies to optimize pain control, perceptions of patient respect and dignity, perceptions of surgeon availability, discharge medication understanding, and overall experience. Also, we identified a need in our department for timely patient feedback, improved communication styles in our staff and trainees, and an internal curriculum offering additional training for our staff and residents. We anticipate that the current results would be of significant interest to other departments wishing to optimize their PE profile as part of the ongoing quality improvement process at hospitals across North America.

Native Coronary Disease Progression Post Coronary Artery Bypass Grafting

BACKGROUND

It remains unclear if graft type impacts native disease progression in the target coronary artery post coronary artery bypass grafting (CABG).

METHODS

Patients who underwent repeat angiograms at least 6 months post CABG with ≥1 arterial graft were included. Pre/post CABG angiograms were examined by 2 experienced readers. Progression was defined as new stenosis of ≥50% in a previously normal coronary, an increase in previous stenosis of ≥20%, or a new occlusion. Primary outcome was the occurrence of native disease progression in bypassed vessels. Secondary outcomes included complete occlusion, left main (LM) and distal disease progression. Cox-proportional hazard regression models were used for time-to-event outcomes.

RESULTS

Study population included 98 patients comprising 263 grafts (143 arterial/120 venous grafts). Median time from surgery to catheterization was 559 days (Interquartile Range 374,910).Ninety-one target vessels showed progression (34.6%) with 75 to complete occlusion (28.5%). Progression was not associated with graft choice (HR 0.74(0.49,1.13) p = 0.163),but was significantly associated with age(p = 0.034),previous PCI(p = 0.002),ACE inhibitor (ACEi) use(p < 0.001),CAD severity (p < 0.001),CCS class III/IV(p = 0.016) and NYHA class III/IV(p < 0.001). Progression to occlusion was significantly associated with SVG (p = 0.019), as well as previous percutaneous coronary intervention (p = 0.007) and ACEi use (p < 0.001). LM disease progression was significantly associated with peripheral vascular disease (HR 5.44(1.92, 15.46), p = 0.001), and not affected by graft type (p = 0.754).

CONCLUSIONS

Native CAD progression in non-LM coronaries is multifactorial, while SVG use was only associated with occlusion of non-LM coronaries. The implications of this study warrant consideration for increased arterial grafting in CABG patients, while the negative associations of previous PCI and ACEi use carry important clinical implications, which require further investigation.

Impact of patient characteristics on the Canadian Patient Experiences Survey-Inpatient Care: survey analysis from an academic tertiary care centre

OBJECTIVE

To determine the role of patient demographics, care domains and self-perceived health status in the analysis and interpretation of results from the Canadian Patient Experience Survey-Inpatient Care.

DESIGN

Cross-sectional survey.

SETTING

Single large Canadian two campus tertiary care academic centre.

PARTICIPANTS

Random sampling of hospital patients postdischarge.

INTERVENTION AND MAIN OUTCOME MEASURES

Logistic regression models were developed to analyse topbox scoring on four questions of global care (rate experience, recommend hospital, rate hospital, overall helped). Means of each composite domain were correlated to the four overall scores at the patient level to determine Spearman's rank correlation coefficients which were plotted against the overall (hospital) domain score for the key driver analysis.

RESULTS

Topbox scoring was decreased with worse degrees of perceived physical and mental health in all four global questions (p<0.05). Female gender and higher levels of education were associated with worse scoring on rate experience, recommend hospital and rate hospital (p<0.001). Whereas there was a significant difference between hospital departments in unadjusted measures, these differences were no longer evident after adjustment with patient covariates. Key driver analysis identified person-centred care, care transition and the domain related to emergency admission as areas of highest potential for improvement.

CONCLUSIONS

Global measures of overall care are influenced by patient-perceived physical and mental health. Caution should be exercised in using patient-satisfaction surveys to compare performance between different healthcare provision entities, as apparent differences could be explained by variation in patient mix rather than variation in performance.

Displacement of Fibrin-bound Thrombin by r-Hirudin Precludes the Use of 131l-r-Hirudin for Detecting Pulmonary Emboli in the Rabbit

Pulmonary emboli are detectable by filling defects in the pulmonary vasculature upon pulmonary angiography. Emboli derived from venous thrombi are rich in fibrin to which thrombin remains bound. Hirudin, a specific thrombin inhibitor, binds to thrombin to yield a 1:1 stoichiometric complex. We examined whether 131I-recombinant hirudin (r-hirudin) could be used to detect pulmonary emboli in rabbits. Clots were formed by re-calcifying rabbit plasma in vitro, and then injected (0.034 ml) into a femoral vein to lodge in the lungs. 131I-r-hirudin (29 ± 4 μCi/kg) was injected intravenously but emboli could not be detected by gamma camera in real time. Post-mortem analysis of lung tissue showed that 131I-r-hirudin did not associate with emboli prepared with 125I-fibrin. Because of these findings, we used different techniques to look at the binding of hirudin to plasma clots. Clots formed in vitro were incubated with 131I-r-hirudin in the presence of equimolar amounts of 125I-albumin; specific binding of 131I-r-hirudin was not observed. Experiments with immobilized fibrin(ogen) showed that 125I-r-hirudin did not bind to and remain with fibrin-bound 131I-thrombin but did lead to the inactivation and displacement of up to 70% of bound thrombin as r-hirudin-thrombin complex; residual thrombin bound to fibrin remained active. Thus, released r-hirudin-thrombin complex is probably cleared rapidly from the region of the embolus in vivo; radioiodinated r-hirudin may not, therefore, be useful as a marker for detecting emboli.

Platelet Accumulation on Fibrin-coated Polyethylene: Role of Platelet Activation and Factor XIII

Platelet accumulation on small- and medium-calibre vascular grafts plays a significant role in graft occlusion. We examined platelet accumulation on the surface of fibrin-coated polyethylene tubing (internal diameter 0.17 cm) during 10 min of flow (l0ml/min) at high wall shear rate (764 s-1). Washed platelets labelled with 51Cr were resuspended in Tyrode solution containing albumin, apyrase and red blood cells (hematocrit 40%). When the thrombin that was used to form the fibrin-coated surface was inactivated with FPRCH2C1 before perfusion of the tubes with the platelet:red blood cell suspension, the accumulation of platelets was 59,840 ± 27,960 platelets per mm2, whereas accumulation on fibrin with residual active thrombin was 316,750 ± 32,560 platelets per mm2 (n = 4). When the fibrin on the surface was cross-linked by including recombinant factor XIII (rFXIII) in the fibrinogen solution used to prepare the fibrin-coated surface, platelet accumulation, after thrombin neutralization, was reduced by the cross-linking from 46,974 ± 9702 to 36,818 ± 7964 platelets per mm2 (n = 12, p <0.01). Platelet accumulation on tubes coated with D-dimer was ten times less than on tubes coated with D-domain; this finding also supports the observation that cross-linking of fibrin with the formation of γ-γ dimers reduces platelet accumulation on the fibrin-coated surface. Thrombin-activated platelets themselves were shown to cross-link fibrin when they had adhered to it during perfusion, or in a static system in which thrombin was used to form clots from FXIII-free fibrinogen in the presence of platelets. Thus, cross-linking of fibrin by FXIII in plasma or from platelets probably decreases the reactivity of the fibrin-containing thrombi to platelets by altering the lysine residue at or near the platelet-binding site of each of the γ-chains of the fibrinogen which was converted into the fibrin of these thrombi.

The Effect of Antithrombin III-Independent Thrombin Inhibitors and Heparin on Fibrin Accretion onto Fibrin-Coated Polyethylene

Prosthetic vascular grafts become coated with a layer of fibrin that contributes to graft thrombosis and occlusion. We compared the effect of antithrombin III-independent inhibitors of thrombin with heparin for their ability to prevent fibrin accretion onto a model of a vascular graft formed in vitro by coating polyethylene tubing with thrombin bound to a layer of polymerized fibrin. Equivalent antithrombin concentrations of heparin, D-Phe-Pro-Arg CH2Cl (PPACK), recombinant hirudin (r-hirudin), and Hirulog-1 were added to barium chloride-adsorbed plasma containing radiolabelled fibrinogen. Whereas, PPACK and r-hirudin persistently inhibited fibrin accretion, the inhibition by heparin was transient. Hirulog-1 had no effect on early fibrin accretion and was actually associated with enhanced accretion at 30 min (control 11.7 ± 2.0 μg fibrin/cm2; Hirulog-1, 18.4 ± 3.5 μg fibrin/cm2, p <0.001). Both Hirulog-1 and r-hirudin displaced radiolabelled thrombin from the fibrin surface. Whereas hirudin-thrombin complexes are stable, Hirulog-1 produces only transient inhibition of the displaced thrombin thereby accounting for the enhanced fibrin accretion with this anticoagulant. These studies show that the antithrombin III-independent inhibitors, r-hirudin and PPACK, are more effective inhibitors of fibrin accretion onto fibrin-coated polyethylene than heparin or Hirulog-1. In addition, they emphasize the importance of determining the ability of anticoagulants to displace thrombin from fibrin and to form stable thrombin-inhibitor complexes; lack of stability of thrombin-inhibitor complexes must be countered by levels of anticoagulant that are adequate to maintain its effectiveness.