Outcomes of different aortic arch replacement techniques

Background

Consensus on the best treatment for aortic arch pathology is unresolved due to an emerging variety of procedures. We aimed to compare the outcomes of two major techniques for open aortic arch replacement involving the supra‐aortic branches and to identify the risk factors for specific adverse events.

Methods

Between 1974 and 2017, 172 patients were treated with either the en bloc (island, n = 59; 34.3%) or branched graft technique (n = 113, 65.7%). Most of the patients were treated in an emergent/urgent setting (52.4%).

Results

Patients who underwent the en bloc procedure had significantly shorter cardiopulmonary bypass (median: 241 vs 271 minutes, P = .041) and aortic cross clamp times (median: 124 vs 168 minutes, P = .005) than patients who underwent the separate graft technique. Overall, the hospital mortality was lower in the en bloc group, 8.5% vs 19.5%, although the difference was not significant (P = .077). No difference was found in the survival between the separate graft and en bloc groups at 1 (77.0 vs 86.3%), 5 (67.7 vs 66.3%) and 10 years (42.4 vs 51.3%), (P = .63). The postoperative stroke rate was comparable between the en bloc and separate graft cohorts (14.3 vs 19.6%, P = .52). Diabetics and those who underwent an elephant trunk procedure were at a higher risk for reintervention.

Conclusions

The separate graft technique, which is more common today, showed no difference from the en bloc technique with regard to hospital mortality and morbidity. Furthermore, the late survival and reintervention rates were similar after both procedures.

Individualized dynamic prediction of survival with the presence of intermediate events

Often, in follow-up studies, patients experience intermediate events, such as reinterventions or adverse events, which directly affect the shapes of their longitudinal profiles. Our work is motivated by two studies in which such intermediate events have been recorded during follow-up. In both studies, we are interested in the change of the longitudinal evolutions after the occurrence of the intermediate event and in utilizing this information to improve the accuracy of dynamic prediction of their risk. To achieve so, we propose a flexible joint modeling framework for longitudinal and time-to-event data, which includes features of the intermediate event as time-varying covariates in both the longitudinal and survival submodels. We consider a set of joint models that postulate different effects of the intermediate event in the longitudinal profile and the risk of the clinical endpoint, with different formulations for the association structure while allowing its functional form to change after the occurrence of the intermediate event. Based on these models, we derive dynamic predictions of conditional survival probabilities which are adaptive to different scenarios with respect to the occurrence of the intermediate event. We evaluate the predictive accuracy of these predictions with a simulation study using the time-dependent area under the receiver operating characteristic curve and the expected prediction error adjusted to our setting. The results suggest that accounting for the changes in the longitudinal profiles and the instantaneous risk for the clinical endpoint is important, and improves the accuracy of the dynamic predictions.

Outcomes after surgery for functional tricuspid regurgitation: a systematic review and meta-analysis

Aims 

This study aims to provide a contemporary overview of outcomes after tricuspid valve (TV) surgery for functional tricuspid regurgitation (TR).

Methods and results 

The literature was systematically searched for papers published between January 2005 and December 2017 reporting on clinical/echocardiographic outcomes after TV surgery for functional TR. A random effects meta-analysis was conducted for outcome variables, and late outcomes are visualized by pooled Kaplan–Meier curves. Subgroup analyses were performed for studies with a within-study comparison of suture vs. ring repair and flexible vs. rigid ring repair. Eighty-seven publications were included, encompassing 13 184 patients (mean age: 62.1 ± 11.8 years, 55% females). A mitral valve procedure was performed in 92% of patients. Pooled mean follow-up was 4.0 ± 2.8 years. Pooled early mortality was 3.9% (95% CI: 3.2–4.6), and late mortality rate was 2.7%/year (95% CI: 2.0–3.5), of which approximately half was cardiac-related 1.2%/year (95% CI: 0.8–1.9). Pooled risk of early moderate-to-severe TR at discharge was 9.4% (95% CI: 7.0–12.1). Late moderate-to-severe TR rate after discharge was 1.9%/year (95% CI: 1.0–3.5). Late reintervention rate was 0.3%/year (95% CI: 0.2–0.4). Mortality and overall (early and late) TR rate were comparable between suture vs. ring annuloplasty (14 studies), whereas overall TR rate was higher after flexible ring vs. rigid ring annuloplasty (6 studies) (7.5%/year vs. 3.9%/year, P = 0.002).

Conclusion 

This study shows that patients undergoing surgery for functional tricuspid regurgitation (FTR) have an acceptable early and late mortality. However, TR remains prevalent after surgery. The results of this study can be used to inform patients and clinicians about the expected outcome after surgery for FTR and can results serve as a benchmark for the performance of emerging transcatheter TV interventions.

Effectiveness of adherence to a preoperative antiplatelet and anticoagulation cessation protocol in cardiac surgery

OBJECTIVES

Reduction of blood loss after cardiac surgery remains challenging. The effectiveness of adherence to a protocol on cessation of anticoagulants and platelet-inhibiting medications was investigated together with the influence of protocol violations on blood loss after surgery, use of blood products, surgical re-explorations and 30-day mortality.

METHODS

Between 2009 and 2013, data were collected prospectively for all elective cardiac surgery procedures in adult patients (n = 1637). Two groups were distinguished: Group 1 adhered to the protocol for cessation or continuation of medication (n = 1287, 79%) and Group 2 violated the protocol (n = 350, 21%).

RESULTS

Median blood loss was 300 ml (interquartile range 175-500 ml). Eighty patients underwent re-exploration due to blood loss (5%). Thirty-day mortality was 2% (n = 27). Protocol violation was associated with increased blood loss [median 275 ml (175-475 ml) vs 350 ml (250-612); P ≤ 0.001] and with increased average use of fresh frozen plasma (226 ml vs 139 ml; P  << 0.00001), red blood cell transfusion (115 ml vs 87 ml; P = 0.081) and thrombocyte transfusions (52 ml vs 37 ml; P = 0.0082). The number of re-explorations (4% vs 6%; P = 0.39) and mortality risk (1% vs 2%; P = 0.72) did not differ.

CONCLUSIONS

Balancing the benefit of continuing platelet inhibitors or anticoagulants versus cessation before surgery remains challenging. Adherence to the protocol will lead to lower blood loss and in a lower consumption of blood products although the decision to go for re-exploration and 30-day mortality does not differ compared with the protocol violation. Stopping medication does not lead to thromboembolic events.

Statistical primer: performing repeated-measures analysis

Longitudinal data arise when repeated measurements are taken on the same individuals over time. Inference about between-group differences of within-subject change is usually of interest. This statistical primer for cardiothoracic and vascular surgeons aims to provide a short and practical introduction of biostatistical methods on how to analyse repeated-measures data. Several methodological approaches for analysing repeated measures will be introduced, ranging from simple approaches to advanced regression modelling. Design considerations of studies involving repeated measures are discussed, and the methods are illustrated with a data set measuring coronary sinus potassium in dogs after occlusion. Cardiothoracic and vascular surgeons should be aware of the myriad approaches available to them for analysing repeated-measures data, including the relative merits and disadvantages of each. It is important to present effective graphical displays of the data and to avoid arbitrary cross-sectional statistical comparisons.

Reconstructive surgery for Ebstein anomaly: three decades of experience

OBJECTIVES

Since 1988, our centre employs vertical plication repair with deattachment and reattachment of the tricuspid valve for Ebstein anomaly. This study describes the characteristics and long-term outcomes of our single-centre cohort.

METHODS

Data from all patients operated on between 1988 and 2016 were retrospectively collected. Kaplan-Meier analyses were done for survival data and mixed models were used to analyse longitudinally collected clinical and echocardiography data.

RESULTS

Thirty-six patients (mean age: 25.4 ± 15.9 years, 36% male) were operated on using the Carpentier-Chauvaud 21 (58%) or Cone repair 15 (42%). One patient (3%) died in hospital. Two late deaths were observed, yielding a survival of 97 ± 3% at 25 years. Reoperation was performed in 6 patients after a mean follow-up of 14.1 ± 10.3 years, resulting in a freedom of reoperation of 80 ± 8% at 25 years. During follow-up, predicted probability of being in New York Heart Association III/IV did not exceed 10%. Modelling longitudinal evolution of tricuspid regurgitation showed no major changes over time. Additionally, a rigid ring repair was associated with a higher probability of tricuspid regurgitation, especially after the first years after the operation. A full Cone repair was associated with less progression of tricuspid regurgitation over time.

CONCLUSIONS

Repair of Ebstein abnomaly is associated with low mortality and morbidity, acceptable reoperation rate and excellent valve function over time, especially in patients with completed Cone repair. Therefore, we conclude that in our centre, repair of Ebstein abnomaly is a durable technique to treat patients.

Downsized cryopreserved and standard-sized allografts for right ventricular outflow tract reconstruction in children: long-term single-institutional experience

OBJECTIVES

The objective of this study was to determine long-term results with bicuspidalized allografts compared to non-bicuspidalized allografts in children under 2 years undergoing primary correction of the right ventricular outflow tract.

METHODS

Thirty-five consecutive bicuspidalized allografts were compared to 45 consecutive non-bicuspidalized allografts implanted during the same period. Valve-related events were analysed with Kaplan-Meier and Cox-regression techniques. Mixed-effects modelling was used to analyse serial echocardiographic measurements of pulmonary gradient. In addition, a systematic review with meta-analysis of the published literature concerning implantation of bicuspidalized allografts was performed.

RESULTS

Perioperative characteristics and in-hospital mortality [bicuspidalized 5 (14.3%), non-bicuspidalized 6 (13.3%)] were comparable (P = 0.902). Bicuspidalized allografts were smaller (14.7 vs 16.5 mm, P = 0.023) and always (100%) of pulmonary origin compared to 26 (57.8%) of the standard-sized allografts. There were no differences in late mortality between the bicuspidalized and non-bicuspidalized group (6.7% vs 7.7%, P = 0.798) or freedom from allograft replacement at 10 years (82 ± 10% and 71 ± 8%, for bicuspidalized and non-bicuspidalized allografts, respectively). Evolution of peak pulmonary gradient (P = 0.273) was comparable between bicuspidalized and non-bicuspidalized allografts. Meta-analysis showed a pooled early and late mortality for bicuspidalized allograft patients of 10.72% [95% confidence interval (CI) 6.13-18.75] and 1.6% per year (95% CI 0.99-2.79), respectively. Pooled estimated late reintervention and replacement rates were 5.94% per year (95% CI 3.42-10.30) and 3.78% per year (95% CI 2.69-5.32), respectively.

CONCLUSIONS

Bicuspidalization seems to be a viable alternative to combat limited supply of small-sized allografts with acceptable survival and reintervention rates comparable to non-bicuspidalized allografts.

Atrioesophageal Fistula after Minimally Invasive Video-Assisted Epicardial Ablation for Lone Atrial Fibrillation

Minimally invasive video-assisted epicardial beating heart ablation for lone atrial fibrillation claims to be safe and effective. We, however, report on three patients with an atrioesophageal fistula after this procedure. The exact pathogenesis of this complication is unknown. All patients presented around 6 weeks after surgery with either fever or neurological deficits. Diagnosis can be made by computed tomography scan. We advocate an aggressive surgical approach with closure of the atrial defect on cardiopulmonary bypass and closure and reinforcement of the esophagus with an intercostal muscle flap in a single-stage surgery. Some caution as to the low-risk character of this procedure seems to be realistic.

Male-female differences and survival in patients undergoing isolated mitral valve surgery: a nationwide cohort study in the Netherlands

OBJECTIVES

The objective of this study was to compare male-female differences with respect to baseline characteristics and short-term outcome in a contemporary nationwide cohort of patients who underwent isolated mitral valve (MV) surgery.

METHODS

All patients [N = 3411; 58% males (N = 1977)] who underwent isolated MV surgery (replacement: N = 1048, 31%; reconstruction: N = 2364, 69%) in the Netherlands between January 2007 and December 2011 were included in this study. Differences in patient and procedural characteristics and in-hospital outcome were compared between male and female patients.

RESULTS

Female patients were generally older (mean age, 64 vs 61 years, P < 0.001), presented more often with pulmonary hypertension (P = 0.03) and had higher logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) I (P < 0.001). Male patients presented more often with prior coronary artery bypass graft surgery (P < 0.001) and active endocarditis (P = 0.002). Female patients underwent MV replacement more often (P < 0.001) and, in case of replacement, received stented bioprostheses more often (P < 0.001). In-hospital mortality rates after MV replacement were 7% (n = 33) and 7% (n = 40) in male and female patients, respectively (OR 1.08, 95% CI 0.67-1.75; P = 0.75). In-hospital mortality rates after MV reconstruction were 1.4% (n = 21) and 1.3% (n = 11) in male and female patients, respectively (OR 0.88, 95% CI 0.42-1.84; P = 0.74).

CONCLUSIONS

There are substantial male-female differences in patient presentation and procedural aspects in isolated MV surgery in the Netherlands. Female patients are older, have more severe disease at the time of surgery and undergo valve repair less often. Future studies are needed to identify potentially modifiable patient factors to improve the outcome of female patients with MV disease.

Prosthetic valve endocarditis due to Propionibacterium acnes

OBJECTIVES

To study the characteristics of patients with Propionibacterium acnes prosthetic valve endocarditis (PVE) who required surgery.

METHODS

A single-centre retrospective cohort study was conducted during a 7-year period. Patients with definite infective P. acnes endocarditis, according to the modified Duke criteria, were included. An extended culture protocol was applied. Information on medical health status, surgery, antibiotic treatment and mortality was obtained.

RESULTS

Thirteen patients fulfilled the criteria for P. acnes endocarditis (0.53% of 2466 patients with valve replacement in a 7-year period). All patients were male and had a previous valve replacement. The health status of patients was poor at diagnosis of P. acnes PVE. Most patients (11 of 13, 85%) were admitted with signs of heart failure due to a significant paravalvular leak; 2 of 13 (15%) patients presented with septic emboli. Twelve patients needed redo surgery, whereas one could be treated with antibiotic therapy only. The time between the index surgery and presentation with P. acnes PVE varied between 5 and 135 months (median 26.5 months). Replacement and reconstruction of the dysfunctional valve and affected anatomical structures was mainly performed with a mechanical valve (n = 5, 42%) or a (bio-) Bentall prosthesis (n = 6, 50%). Antibiotic therapy consisted of penicillin with or without rifampicin for 6 weeks after surgery. The mortality in this series was low (n = 1, 8%) and no recurrent endocarditis was found during a median follow-up of 38 months.

CONCLUSIONS

Propionibacterium acnes PVE is a rare complication after valve surgery. Redo surgery is often required. Treatment of the dysfunctional prosthetic aortic valve most often consists of root replacement, in combination with antibiotic therapy.

Contemporary outcomes after surgical aortic valve replacement with bioprostheses and allografts: a systematic review and meta-analysis

Many observational studies have reported outcomes after surgical aortic valve replacement (AVR), but there are no recent systematic reviews and meta-analyses including all available bioprostheses and allografts. The objective of this study is to provide a comprehensive and up-to-date overview of the outcomes after AVR with bioprostheses and allografts reported in the last 15 years. We conducted a systematic literature review (PROSPERO register: CRD42015017041) of studies published between 2000–15. Inclusion criteria were observational studies or randomized controlled trials reporting on outcomes of AVR with bioprostheses (stented or stentless) or allografts, with or without coronary artery bypass grafting (CABG) or valve repair procedure, with study population size n ≥ 30 and mean follow-up length ≥5 years. Fifty-four bioprosthesis studies and 14 allograft studies were included, encompassing 55 712 and 3872 patients and 349 840 and 32 419 patient-years, respectively. We pooled early mortality risk and linearized occurrence rates of valve-related events, reintervention and late mortality in a random-effects model. Sensitivity, meta-regression and subgroup analyses were performed to investigate the influence of outliers on the pooled estimates and to explore sources of heterogeneity. Funnel plots were used to investigate publication bias. Pooled early mortality risks for bioprostheses and allografts were 4.99% (95% confidence interval [CI], 4.44–5.62) and 5.03% (95% CI, 3.61–7.01), respectively. The late mortality rate was 5.70%/patient-year (95% CI, 4.99–5.62) for bioprostheses and 1.68%/patient-year (95% CI, 1.23–2.28) for allografts. Pooled reintervention rates for bioprostheses and allografts were 0.75%/patient-year (95% CI, 0.61–0.91) and 1.87%/patient-year (95% CI, 1.52–2.31), respectively. There was substantial heterogeneity in most outcomes. Meta-regression analyses identified covariates that could explain the heterogeneity: implantation period, valve type, patient age, gender, pre-intervention New York Heart Association class III/IV, concomitant CABG, study design and follow-up length. There is possible publication bias in all outcomes. This comprehensive systematic review and meta-analysis provides an overview of the outcomes after AVR with bioprostheses and allografts reported during the last 15 years. The results of this study can support patients and doctors in the prosthetic valve choice and can be used in microsimulation models to predict patient outcomes and estimate the cost-effectiveness of AVR with bioprostheses or allografts compared with current and future heart valve prostheses.

Intermittent warm blood versus cold crystalloid cardioplegia for myocardial protection: a propensity score-matched analysis of 12-year single-center experience

Objectives:

This study analyzes the efficacy in myocardial protection of two types of cardioplegia solutions, namely, blood and crystalloid cardioplegia, both given intermittently in patients undergoing coronary artery bypass grafting (CABG).

Methods:

Adult patients undergoing primary isolated coronary artery bypass grafting between January 1998 and January 2011 with cardiopulmonary bypass, using either blood or crystalloid cardioplegia, were identified in our database. Propensity score matching was performed to create comparable patient groups. Multivariate logistic regression analysis was performed to identify independent risk factors for perioperative myocardial damage. The primary endpoint of the study was the maximum creatine kinase-MB (CK-MB) value within 5 days postoperatively with a cut-off point of 100 U/L. Early mortality and perioperative low cardiac output syndrome in both groups were compared.

Results:

The study included 7138 CABG patients: 3369 patients using crystalloid cardioplegia and 3769 using blood cardioplegia. After propensity score matching, 2585 patients per study group remained for the analysis. Wilcoxon signed-rank test revealed significantly higher CK-MB levels in patients operated with the use of blood cardioplegia. Multivariate regression analysis identified blood cardioplegia as an independent risk factor for elevated CK-MB levels. However, it was associated with lower aspartate aminotransferase (AST) levels. The type of cardioplegia had no influence on early mortality, postoperative low cardiac output syndrome or intensive care unit stay.

Conclusions:

Blood cardioplegia was identified as an independent risk factor for elevated levels of CK-MB after CABG, but was associated with lower AST levels. The authors conclude that the type of cardioplegia had no significant influence on clinical outcome.

Clinical outcome of the PAS-Port® proximal anastomosis system in off-pump coronary artery bypass grafting in 201 patients

AIM

The PAS-Port® Proximal Anastomosis System (Cardica, Inc, Redwood City, CA, USA) has been used worldwide since March 2003. The objective of the present study was to evaluate the clinical outcome of the PAS-Port® Proximal Anastomosis System.

METHODS

All the patients who underwent off-pump coronary artery bypass grafting in the Catharina Hospital Eindhoven between August 2006 and April 2010 were included in a non-randomized retrospective case-control study, if they had at least one proximal vein graft anastomosis. Study end-points consisted of overall survival, coronary reintervention and postoperative stroke.

RESULTS

The study included 312 patients (201 cases, 111 controls). After 36 months of follow-up there was no difference in survival between cases and controls (92.2% vs. 93.7%, P=0.52). No significant difference could be detected between cases and controls with respect to overall coronary reintervention-free survival (93% vs. 96.4%, P=0.20) and freedom from coronary reintervention due to proximal vein graft failure (98% vs. 100% P=0.14). The use of the PAS-Port system could not be identified as an independent risk factor of coronary reintervention (p=0.21). Postoperative stroke rates of cases and controls (2% vs. 0.9%, P=0.42) were comparable.

CONCLUSION

The clinical outcomes in patients treated with the PAS-Port® Proximal Anastomosis System were satisfactory compared with those treated with the conventional hand-sewing technique. The use of the PAS-Port system was not associated with higher adverse outcome in terms of overall survival, stroke, coronary reintervention-free survival and freedom from reintervention due to proximal vein graft failure.