Long-term survival after coronary bypass surgery with multiple versus single arterial grafts.

OBJECTIVES: This study sought to evaluate the long-term differences in survival between multiple arterial grafts (MAG) and single arterial grafts (SAG) in patients who underwent coronary artery bypass grafting (CABG) in the SYNTAX study. METHODS: The present analysis included the randomized and registry-treated CABG patients (n = 1509) from the SYNTAX Extended Survival study (SYNTAXES). Patients with only venous (n = 42) or synthetic grafts (n = 1) were excluded. The primary end point was all-cause death at the longest follow-up. Multivariable Cox regression was used to adjust for differences in baseline characteristics. Sensitivity analysis using propensity matching with inverse probability for treatment weights was performed. RESULTS: Of the 1466 included patients, 465 (31.7%) received MAG and 1001 (68.3%) SAG. Patients receiving MAG were younger and at lower risk. At the longest follow-up of 12.6 years, all-cause death occurred in 23.6% of MAG and 40.0% of SAG patients [adjusted hazard ratio (HR) 0.74, 95% confidence interval (CI) (0.55-0.98); P = 0.038], which was confirmed by sensitivity analysis. MAG in patients with the three-vessel disease was associated with significant lower unadjusted and adjusted all-cause death at 12.6 years [adjusted HR 0.65, 95% CI (0.44-0.97); P = 0.033]. In contrast, no significance was observed after risk adjustment in patients with the left main disease, with and without diabetes, or among SYNTAX score tertiles. CONCLUSIONS: In the present post hoc analysis of all-comers patients from the SYNTAX trial, MAG resulted in markedly lower all-cause death at 12.6-year follow-up compared to a SAG strategy. Hence, this striking long-term survival benefit of MAG over SAG encourages more extensive use of multiple arterial grafting in selected patients with reasonable life expectancy. TRIAL REGISTRATION: SYNTAXES ClinicalTrials.gov reference: NCT03417050; SYNTAX ClinicalTrials.gov reference: NCT00114972.

Recovery of conduction disorders after sutureless aortic valve replacement.

OBJECTIVES: Conduction disorders and the need for permanent pacemaker (PPM) implantation after surgical aortic valve replacement are well-recognized complications. However, in the case of sutureless valve prostheses, it remains unknown whether pacemaker (PM) dependency and conduction disturbances resolve over time. Our aim was to evaluate whether conduction disorders after Perceval sutureless valve implantation recover during follow-up. METHODS: Patients undergoing isolated surgical aortic valve replacement or concomitant aortic valve replacement with coronary artery bypass surgery using the Perceval sutureless valve, between January 2010 and July 2018, were included. Postoperative electrocardiogram findings were analysed to determine the incidence of new-onset left bundle branch blocks (LBBBs) and the requirement for PPM implantation. During a postoperative period of 6-18 months, electrocardiogram findings during PM checks were analysed to determine PM dependency and LBBB persistence. RESULTS: Out of 184 patients who received a Perceval prosthesis during the study period, 39 (21.2%) patients developed new-onset LBBB and 10 patients (5.4%) received a PPM postoperatively. The occurrence of conduction disorders was not associated with valve size. Follow-up was completed in 176 (95.7%) patients. In patients with a new-onset LBBB, 35.9% recovered during follow-up (P = 0.001). Seven out of 10 (70%) patients remained PM dependent. CONCLUSIONS: After Perceval aortic valve implantation, new-onset LBBB recovers in more than one-third of patients during follow-up. In patients who needed a postoperative PPM, the majority remained PM dependent.

Acute isotonic hyponatremia after single dose histidine-tryptophan-ketoglutarate cardioplegia: an observational study.

INTRODUCTION: Histidine-tryptophan-ketoglutarate cardioplegia is used for prolonged myocardial protection in complex cardiac surgery. Administration leads to acute hyponatremia in a majority of patients, because of its low sodium concentration (15 mmol/L). However, histidine-tryptophan-ketoglutarate solution's osmolality is slightly hypertonic (310 mOsm/kg). Hypothesized was that acute isotonic hyponatremia will be induced, which does not need to be corrected with hypertonic saline. METHODS: Cardiac surgery patients who received histidine-tryptophan-ketoglutarate cardioplegia were included in this prospective single center study. Serial blood samples were taken from each patient at five different time points: after induction of anesthesia (T1) and 10 minutes (T2), 6 hours (T3), 12 hours (T4), and 18 hours (T5) after administration of histidine-tryptophan-ketoglutarate cardioplegia, respectively. Blood samples were analyzed for sodium concentration, osmolality, and acid-base balance. RESULTS: Twenty-five patients were included. Median blood sodium levels decreased from 140 [138-141] at T1 to 128 [125-130] mmol/L at T2 (p < 0.001). At T3, T4, and T5, median blood sodium concentrations were 136 [134-138], 139 [137-140], and 140 [137-142] mmol/L, respectively. Median osmolality was 289 [286-293] at T1 and increased to 296 [291-299] mOsm/kg (p < 0.001) at T2. At T3, T4, and T5, osmolality was 298 [292-302], 298 [294-304], and 300 [297-306] mOsm/kg, respectively. Median pH decreased from 7.38 [7.36-7.40] at T1 to 7.30 [7.27-7.32] at T2 (p < 0.001). CONCLUSION: Administration of histidine-tryptophan-ketoglutarate cardioplegia during cardiac surgery leads to acute moderate to severe isotonic hyponatremia, which resolves spontaneously in the first 18 hours perioperatively. Correction with hypertonic saline is not necessary.

Unraveling postoperative alterations after mitral valve replacement with three-dimensional printing.

Mitral valve (MV) surgery is the second most performed valve operation in Europe. MV pathology is associated with atrial fibrillation, and, therefore, frequently combined with rhythm surgery and left atrial appendage exclusion (LAAE). Currently, no guidelines exist regarding the follow up after LAAE postoperative. Postoperative imaging with computed tomography (CT), in the absence of complaints, will inherently reveal unsuspected cardiac and noncardiac findings with potential clinical significance. However, poststernotomy alterations are nonspecific and often overlap with normal postoperative changes and could, therefore, not directly be recognized. Virtual three-dimensional (3D) CT reconstructions can help us to visualize 2D structures, especially in areas where structures overlap like coronary arteries or when devices (atrial clip, MV prosthesis) cause scattering artifacts. Advanced imaging reconstructions and 3D printing can enhance understanding of the cardiac anatomy in the postoperative phase and help us to determine follow-up strategies.

Clamping versus nonclamping thoracoscopic box ablation in long-standing persistent atrial fibrillation.

OBJECTIVE: To compare clinical outcomes of clamping devices and linear nonclamping devices for isolation of the posterior left atrium (box) in thoracoscopic ablation of long-standing persistent atrial fibrillation. METHODS: Eighty patients who underwent thoracoscopic pulmonary vein and box isolation using a bipolar clamping device (42 patients) or bipolar nonclamping device (38 patients) to create the roof/inferior lesions for box isolation were included from 2 centers. Follow-up consisted of 24-hour Holter at regular intervals. Freedom from AF during 1-year follow-up and catheter repeat interventions were compared between groups. RESULTS: Acute intraoperative electrical isolation of the box compartment was significantly higher in the clamping group than in the nonclamping group (100% and 79%, respectively, P < .01). At 1-year follow-up, 91% of the clamping group and 79% of the nonclamping group were in sinus rhythm. During 1-year follow-up, recurrence rates did not significantly differ between the 2 groups (P = .08). Repeat catheter interventions were required in 10% of the clamping group and 21% of the nonclamping group (P = .15). Conduction gaps in the roof or inferior lesions were found in 1 patient (2%) in the clamping group versus 4 patients (11%) in the nonclamping group (P = .13). CONCLUSIONS: Thoracoscopic pulmonary vein and box isolation are highly effective in restoring sinus rhythm in long-standing persistent atrial fibrillation on short-term follow-up. Comparison of clamping and nonclamping devices revealed lower rates of intraoperative exit block of the box in the nonclamping group. However, this did not translate into a significant difference in atrial fibrillation freedom at short-term (1-year) follow-up.

Endocarditis after transcatheter aortic valve replacement; a new nightmare in cardiac surgery.

Treatment of prosthetic valve endocarditis after transcatheter aortic valve replacement (TAVR) remains challenging. An increase in TAVR endocarditis is inevitable, especially with the extension of indications and implantation in low-risk patients. We present a case of complex surgical treatment of prosthetic valve endocarditis after TAVR.

Conduction disorders and impact on survival after sutureless aortic valve replacement compared to conventional stented bioprostheses.

OBJECTIVES: Sutureless and rapid-deployment aortic valve prostheses are frequently used for the treatment of aortic stenosis. However, postoperative left bundle branch block (LBBB) and permanent pacemaker (PPM) implantation have emerged as frequent complications. The aim of this study was to compare the incidence of new-onset LBBB and PPM implantation after sutureless aortic valve replacement (sAVR) with stented bioprostheses, and the impact on postoperative survival. METHODS: Patients undergoing isolated surgical aortic valve replacement (AVR) or concomitant AVR with coronary artery bypass surgery between January 2010 and July 2017 were included in the study. Two groups were defined: sAVR and conventional AVR (cAVR). The findings of preoperative electrocardiograms were compared with postoperative electrocardiogram findings for both groups. The incidence of new-onset LBBB and the requirement for PPM implantation were recorded. The effect of these conduction disorders on late survival was analysed. RESULTS: A total of 987 patients were analysed, consisting of 132 sAVR and 855 cAVR patients. The sAVR group had an increased incidence of new-onset LBBB compared to the cAVR group (16.7% vs 2.3%, P < 0.001). A significantly higher rate of postoperative PPM implantation was found for sAVR patients compared to cAVR (6.8% vs 1.6%, P = 0.001). The multivariate Cox analysis revealed that neither postoperative new-onset LBBB nor PPM implantation was associated with increased mortality (hazard ratio 1.73, 95% confidence interval 0.74-4.03, P = 0.204). CONCLUSIONS: sAVR is associated with an increased risk of new-onset LBBB and PPM requirement compared to cAVR. In this population, postoperative conduction disorders did not affect the mid-term survival.

Thoracoscopic Left Atrial Appendage Clipping: A Multicenter Cohort Analysis.

OBJECTIVES: This study sought to document the closure rate, safety, and stroke rate after thoracoscopic left atrial appendage (LAA) clipping. BACKGROUND: The LAA is the main source of stroke in patients with atrial fibrillation, and thoracoscopic clipping may provide a durable and safe closure technique. METHODS: The investigators studied consecutive patients undergoing clipping as part of a thoracoscopic maze procedure in 4 referral centers (the Netherlands and the United States) from 2012 to 2016. Completeness of LAA closure was assessed by either computed tomography (n = 100) or transesophageal echocardiography (n = 122). The primary outcome was complete LAA closure (absence of residual LAA flow and pouch <10 mm). The secondary outcomes were 30-day complications; the composite of ischemic stroke, hemorrhagic stroke, or transient ischemic attack; and all-cause mortality. RESULTS: A total of 222 patients were included, with a mean age of 66 ± 9 years, and 68.5% were male. The mean CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack or thromboembolism, vascular disease, age 65 to 74 years, sex category [female]) score was 2.3 ± 1.0. Complete LAA closure was achieved in 95.0% of patients. There were no intraoperative or clip-related complications, and the overall 30-day freedom from any complication rate was 96.4%. The freedom from cerebrovascular events after surgery was 99.1% after median follow-up of 20 months (interquartile range: 14 to 25 months; 369 patient-years of follow-up), and overall survival was 98.6%. The observed rate of cerebrovascular events after LAA clipping was low (0.5 per 100 patient-years). CONCLUSIONS: LAA clipping during thoracoscopic ablation is a feasible and safe technique for closure of the LAA in patients with atrial fibrillation. The lower than expected rate of cerebrovascular events after deployment was likely multifactorial, including not only LAA closure, but also the effect of oral anticoagulation and rhythm control.

Significantly Elevated C-Reactive Protein Levels After Epicardial Clipping of the Left Atrial Appendage.

OBJECTIVE: Besides mechanical and anatomical changes of the left atrium, epicardial closure of the left atrial appendage has also possible homeostatic effects. The aim of this study was to assess whether epicardial clipping of the left atrial appendage has different biochemical effects compared with complete removal of the left atrial appendage. METHODS: Eighty-two patients were included and underwent a totally thoracoscopic AF ablation procedure. As part of the procedure, the left atrial appendage was excluded with an epicardial clip (n = 57) or the left atrial appendage was fully amputated with an endoscopic vascular stapler (n = 25). From all patients' preprocedural and postprocedural blood pressure, electrolytes and inflammatory parameters were collected. RESULTS: The mean age and left atrial volume index were comparable between the epicardial clip and stapler group (64 ± 8 years vs. 60 ± 9 years, P = non-significant; 44 ± 15 mL/m vs. 40 ± 13 mL/m, P = non-significant). Patients receiving left atrial appendage clipping had significantly elevated C-reactive protein levels compared with patients who had left atrial appendage stapling at the second, third, and fourth postoperative day (225 ± 84 mg/L vs. 149 ± 76 mg/L, P = 0.002, 244 ± 78 vs. 167 ± 76, P = 0.004, 190 ± 74 vs. 105 ± 48, P < 0.001, respectively). Patients had a significant decrease in sodium levels, systolic, and diastolic blood pressure at 24 and 72 hours after left atrial appendage closure. However, this was comparable for both the left atrial appendage clipping and stapling group. CONCLUSIONS: Increased activation of the inflammatory response was observed after left atrial appendage clipping compared with left atrial appendage stapling. Furthermore, a significant decrease in blood pressure was observed after surgical removal of the left atrial appendage. Whether the inflammatory response affects the outcome of arrhythmia surgery needs to be further evaluated.

Distal anastomotic patency of the Cardica C-PORT(R) xA system versus the hand-sewn technique: a prospective randomized controlled study in patients undergoing coronary artery bypass grafting.

OBJECTIVES: The C-Port® Distal Anastomosis Systems (Cardica, Inc., Redwood City, CA, USA) demonstrated favourable results in feasibility trials. However, distal vein anastomoses created with the C-Port® or C-Port xA® system have never been compared with hand-sewn distal vein anastomoses. The objective of this study was to compare distal end-to-side anastomoses facilitated with the C-Port xA® System with the traditional hand-sewn method. METHODS: This single-centre prospective randomized controlled study comprised 71 patients (device group n = 35, control group n = 36) who underwent primary elective coronary artery bypass grafting between June 2008 and April 2011. The primary study end-point was 12-month distal anastomotic patency, which was assessed with prospective ECG-gated 256-multislice computed tomographic coronary angiography using a step-and-shoot scanning protocol. For the primary end-point, a per-protocol analysis was used. RESULTS: In the device group, four (11%) anastomoses were converted to hand-sewn anastomoses, and additional stitches to achieve haemostasis were necessary in 22 (76%) patients. There was no hospital mortality in either group. During the 12-month follow-up, a single death occurred in the Device group and was unrelated to the device. Twenty-nine patients in the device group and 32 in the control group completed 12-month CT coronary angiography. The overall patency of 160 studied distal vein graft anastomoses was 93%. Comparison of the end-to-side target anastomosis showed 12-month patencies of 86 and 88% in the device group and the control group, respectively. CONCLUSIONS: According to these preliminary results and despite the limited number of patients, the use of the C-Port xA® System is safe enough to perform distal end-to-side vein graft anastomosis, with respect to 12-month end-to-side distal venous anastomotic patency. Although there are some technical challenges with this device, the incidence of complications is comparable to the traditional hand-sewn technique.

A novel low-fidelity simulator for both mitral valve and tricuspid valve surgery: the surgical skills trainer for classic open and minimally invasive techniques.

OBJECTIVES: Simulators have been proven to equip trainee surgeons with better skills than the traditional, standard approach to skill development. The purpose of this study was to develop a low-fidelity, low-cost, reusable and portable simulation device, which could provide training in nearly the full range of mitral valve surgery techniques, in both the classic, open approach as well as the minimally invasive approach. METHODS: This novel simulator is made up of commonly available components. The basic elements are a classic baby bottle, with the associated feeding teat and screw ring, in combination with a sheet of dental dam. The detailed process for making this simulator is outlined in this article. Maximum suture tensile strength on the different components was tested with a digital force gauge. Reusability and the rate of wear as a result of suturing were documented. Total cost was calculated in euros (€). RESULTS: This study resulted in a simulation model very similar in size to the actual anatomical dimensions of the mitral valve. Various pathological conditions, according to Carpentier's Functional Classification, could be simulated. This led to the possibility of providing training in several mitral valve surgical techniques. As the model developed, it became clear that it could also be used to practice tricuspid valve surgery techniques. Maximum mean suture tensions on the silicone teat and dental dam were 42.11 and 11.15 N/m(2), respectively. The feeding teat started wearing after approximately 45 suture placements. Total cost of the study model was €5.14. CONCLUSIONS: This relatively simple, low-cost, low-fidelity model can provide simulation training in nearly the full range of mitral valve and tricuspid valve surgical techniques, in both the classic open approach and the minimally invasive approach-and do so almost anywhere. Especially when used by young cardiothoracic surgeons in training, this model may contribute to the development of technical skills and procedural knowledge required for adequate performance in the operating room.

Resection of a lipomatous hypertrophic interatrial septum involving the right ventricle.

Lipomatous hypertrophy of the interatrial septum is a rare cardiac lesion that is usually limited to the interatrial septum. We report a case of an extensive lipomatous hypertrophy, which protruded into the right and the left atrium as well as the superior and the inferior vena cava and the right ventricle. A 71-year-old woman was referred to us because of a cardiac mass on a transthoracic echocardiogram, performed on a routine check-up because of a known membranous ventricular septum defect. She underwent surgical resection of the mass and closure of the ventricular septum defect. The postoperative period was complicated by superior vena cava syndrome for which she underwent re-operation. The post mortem histopathological diagnosis was a lipomatous hypertrophic interatrial septum.