Postoperative conduction disorders after implantation of the self-expandable sutureless Perceval S bioprosthesis.

BACKGROUND AND AIM OF THE STUDY: Minimally invasive techniques for aortic valve replacement (AVR) have been developed as an alternative to conventional AVR for patients with high operative risk. Yet, these techniques are still associated with an increased risk of postoperative conduction disorders. The study aim was to identify the incidence and fate of postoperative conduction disorders in patients undergoing sutureless (SU) AVR with the Perceval S bioprosthesis. METHODS: In this observational study, patients who underwent SU AVR with the Perceval S prosthesis at the Catharina Hospital, Eindhoven, were analyzed. Electrocardiograms (ECGs) recorded at baseline, within 24 h postoperatively, before hospital discharge and at follow up were collected by reviewing patients' records. The ECGs were analyzed by two independent investigators to record QRS-duration and conduction disorders. RESULTS: All patients (n = 31) who underwent implantation of the Perceval S bioprosthesis between September 2010 and September 2012 were included. At baseline, three patients (9.7%) had preexisting left bundle branch block (LBBB), and one patient (3.2%) had a permanent pacemaker (PPM). New-onset LBBB developed in 11 patients (39.3%), and was transient in three patients (10.7%). Postoperatively, four patients (13.3%) required PPM implantation because of total atrioventricular block; all of these patients had either pre-existing LBBB (n = 1) or new LBBB (n = 3). CONCLUSION: Sutureless AVR with the Perceval S bioprosthesis was frequently complicated by new LBBB, which was persistent in the majority of patients. A relatively high incidence of postoperative PPM implantation was also observed.

Basal protein synthesis rates differ between vastus lateralis and rectus abdominis muscle.

BACKGROUND: In vivo muscle protein synthesis rates are typically assessed by measuring the incorporation rate of stable isotope labelled amino acids in skeletal muscle tissue collected from vastus lateralis muscle. It remains to be established whether muscle protein synthesis rates in the vastus lateralis are representative of muscle protein synthesis rates of other muscle groups. We hypothesized that post-absorptive muscle protein synthesis rates differ between vastus lateralis and rectus abdominis, pectoralis major, or temporalis muscle in vivo in humans. METHODS: Twenty-four patients (62 ± 3 years, 42% female), scheduled to undergo surgery, participated in this study and underwent primed continuous intravenous infusions with l-[ring-13 C6 ]-phenylalanine. During the surgical procedures, serum samples were collected, and muscle tissue was obtained from the vastus lateralis as well as from the rectus abdominis, pectoralis major, or temporalis muscle. Fractional mixed muscle protein synthesis rates (%/h) were assessed by measuring the incorporation of l-[ring-13 C6 ]-phenylalanine into muscle tissue protein. RESULTS: Serum l-[ring-13 C6 ]-phenylalanine enrichments did not change throughout the infusion period. Post-absorptive muscle protein synthesis rates calculated based upon serum l-[ring-13 C6 ]-phenylalanine enrichments did not differ between vastus lateralis and rectus abdominis (0.032 ± 0.004 vs. 0.038 ± 0.003%/h), vastus lateralis and pectoralis major, (0.025 ± 0.003 vs. 0.022 ± 0.005%/h) or vastus lateralis and temporalis (0.047 ± 0.005 vs. 0.043 ± 0.005%/h) muscle, respectively (P > 0.05). When fractional muscle protein synthesis rates were calculated based upon tissue-free l-[ring-13 C6 ]-phenylalanine enrichments as the preferred precursor pool, muscle protein synthesis rates were significantly higher in rectus abdominis (0.089 ± 0.008%/h) compared with vastus lateralis (0.054 ± 0.005%/h) muscle (P < 0.01). No differences were observed between fractional muscle protein synthesis rates in vastus lateralis and pectoralis major (0.046 ± 0.003 vs. 0.041 ± 0.008%/h) or vastus lateralis and temporalis (0.073 ± 0.008 vs. 0.083 ± 0.011%/h) muscle, respectively. CONCLUSIONS: Post-absorptive muscle protein synthesis rates are higher in rectus abdominis when compared with vastus lateralis muscle. Post-absorptive muscle protein synthesis rates do not differ between vastus lateralis and pectoralis major or temporalis muscle. Protein synthesis rates in muscle tissue samples obtained during surgery do not necessarily represent a good proxy for appendicular skeletal muscle protein synthesis rates.

Use of an intraoperative checklist to decrease the incidence of re-exploration for postoperative bleeding after cardiac surgery.

OBJECTIVES: We have implemented an intraoperative checklist aiming to reduce the incidence of re-exploration for bleeding after cardiac surgery. The present report addresses the results of adopting such a checklist regarding the incidence of postoperative bleeding. METHODS: The checklist was implemented by presenting it in several staff meetings of the Catharina Heart Center. Copies of the checklist were presented in every operating room. Data were collected by the Catharina Heart Center, aligned with the 'Meetbaar Beter' data manual and validated by 'Meetbaar Beter' through their data quality system. The incidence of re-exploration for bleeding was analysed in a variable life-adjusted display curve. The patient population operated after the implementation of the checklist was compared with a recent historical population before its implementation. RESULTS: From January 2013 through April 2016, 4817 cardiac surgical procedures were performed in our institution. Before May 2015, 3210 procedures were performed (Group 1), complicated by 112 re-exploration for bleeding (3.5%). The 'reoperation for bleeding checklist' was implemented on 1 May 2015. After this date, the number of re-explorations for bleeding decreased to 29 (1.8%) of the 1607 cardiac surgical procedures (Group 2) (P < 0.05). CONCLUSIONS: An intraoperative checklist is feasible to implement, low cost, quick and simple to measure with a significant reduction in the incidence of re-exploration for bleeding. This report shows an example of the positive effects of transparency in publishing outcomes' data in cardiac surgery.

Perioperative serum aspartate aminotransferase level as a predictor of survival after coronary artery bypass grafting.

BACKGROUND: Elevated cardiac enzymes after coronary artery bypass grafting (CABG) surgery have been identified as a risk factor for worse postoperative outcome. Cardiac enzymes play an important role in the diagnosis of perioperative myocardial infarction. This study aims to investigate the predictive value of aspartate aminotransferase (AST) with respect to early and late mortality after CABG. METHODS: Patients undergoing isolated CABG in a single center between January 1998 and December 2010 were prospectively enrolled in our database. Patients were arbitrarily divided into 4 groups according to the postoperative AST level: group 1 (AST < 50 U/L), group 2 (AST = 51 to 100 U/L), group 3 (AST = 101 to 200 U/L), group 4 (AST = 201 to 300 U/L), and group 5 (AST > 300 U/L). The impact of biomedical variables on early mortality was determined using univariate and multivariate logistic regression analyses. Risk factors for late mortality were identified using Cox proportional hazard regression analyses. RESULTS: The study population consisted of 13,505 patients who underwent isolated CABG. Postoperative AST level was identified as a risk factor for early (odds ratio = 3.6 [2.5 to 5.4], p < 0.0001) and late mortality (hazard ratio = 1.4 [1.2 to 1.7], p < 0.001). After correction for other risk factors, AST level was an independent predictor of worse survival. CONCLUSIONS: Elevated postoperative AST level is an independent predictor of early and late mortality after CABG. Although it is not a specific indicator for cardiac damage, it can reflect ischemic effects on the other organs as an indirect sign of depressed cardiac function.