Cardiac troponin release following coronary artery bypass grafting: mechanisms and clinical implications.

The use of biomarkers is undisputed in the diagnosis of primary myocardial infarction (MI), but their value for identifying MI is less well studied in the postoperative phase following coronary artery bypass grafting (CABG). To identify patients with periprocedural MI (PMI), several conflicting definitions of PMI have been proposed, relying either on cardiac troponin (cTn) or the MB isoenzyme of creatine kinase, with or without supporting evidence of ischaemia. However, CABG inherently induces the release of cardiac biomarkers, as reflected by significant cTn concentrations in patients with uncomplicated postoperative courses. Still, the underlying (patho)physiological release mechanisms of cTn are incompletely understood, complicating adequate interpretation of postoperative increases in cTn concentrations. Therefore, the aim of the current review is to present these potential underlying mechanisms of cTn release in general, and following CABG in particular (Graphical Abstract). Based on these mechanisms, dissimilarities in the release of cTnI and cTnT are discussed, with potentially important implications for clinical practice. Consequently, currently proposed cTn biomarker cut-offs by the prevailing definitions of PMI might warrant re-assessment, with differentiation in cut-offs for the separate available assays and surgical strategies. To resolve these issues, future prospective studies are warranted to determine the prognostic influence of biomarker release in general and PMI in particular.

The prognostic impact of unplanned invasive coronary angiography following coronary artery bypass grafting.

OBJECTIVES: Myocardial ischaemia following coronary artery bypass grafting (CABG) is a potentially devastating complication. Nevertheless, the incidence, aetiology and prognostic relevance of unplanned coronary angiography (uCAG) remain understudied. We aimed to investigate the prevalence and outcome of patients undergoing urgent, uCAG in the postoperative period following CABG. METHODS: We screened all patients undergoing isolated elective CABG in an academic referral centre between 2016 and 2021 and identified patients undergoing uCAG within 30 days of surgery. For uCAG patients, a distinction was made between patients undergoing re-revascularization (REV) and patients receiving conservative management (CON). The primary outcomes were 30-day mortality and unadjusted and adjusted long-term survival. Secondary outcomes were the indication for and prevalence of uCAG and urgent revascularization. RESULTS: Of the 1918 patients undergoing isolated CABG, 78 individuals needed uCAG (4.1%), of whom 45 underwent immediate revascularization (REV group; 2.3% overall, 57% within the uCAG group, median age 69.9 years) and 33 were treated conservatively (CONS group; 1.7% overall, 42% within the uCAG group, median age 69.1 years). Patients undergoing uCAG (n = 78) had a higher 30-day mortality than patients not undergoing uCAG (n = 1840, 30-day mortality: 9.0% vs 0.4%, P < 0.001). Long-term survival was significantly decreased in patients undergoing uCAG in both unadjusted (hazard ratio 2.20, 95% confidence interval 1.30-3.73) and EuroSCORE-, age- and sex-adjusted models (hazard ratio uCAG 2.03, 95% confidence interval 1.16-3.56). CONCLUSIONS: Unplanned postoperative coronary angiography is performed in 4.1% of isolated CABG procedures, and patients in need of such urgent invasive evaluation are subjected to decreased short- and long-term survival.

The evolution of arch surgery: Frozen elephant trunk or conventional elephant trunk?

Treatment of aortic arch aneurysms and dissections require highly complex surgical procedures with devastating complications and mortality rates. Currently, repair of the complete arch until the proximal descending thoracic aorta consists of a two-stage procedure, called elephant trunk (ET) technique, or a single stage a single-stage technique referred to as frozen elephant trunk (FET). There is conflicting evidence about the perioperative results of ET in comparison with FET. We carried out a meta-analysis to investigate possible differences in perioperative and early (up to 30 days) outcomes of ET vs. FET, particularly for mortality, spinal cord injury (SCI), stroke, and renal failure. We also performed a meta-regression to explore the effects of age and sex as possible cofactors. Twenty-one studies containing data from interventions conducted between 1997 and 2019 and published between 2008 and 2021 with 3153 patients (68.5% male) were included. ET was applied to 1,693 patients (53.7%) and FET to 1460 (46.3%). Overall mortality after ET was 250/1693 (14.8%) and after FET 116/1460 (7.9%). Relative risk (RR) and 95% confidence interval (CI) were 1.37 [1.04 to 1.81], p = 0.027. There was no significant effect of age and sex. SCI occurrence after the second stage of ET was 45/1693 (2.7%) and after FET 70/1,460 patients (4.8%) RR 0.53 [0.35 to 0.81], p = 0.004. Age and sex were not associated with the risk of SCI. No significant differences were observed between ET and FET in the incidence of stroke and renal failure. Our results indicate that ET is associated with higher early mortality but lower incidence of SCI compared to FET. When studies published in the last 5 years were analyzed, no significant differences in mortality or SCI were found between ET and FET. This difference is attributed to a decrease in mortality after ET, as the mortality after FET did not change significantly over time.

Homograft durability after correction of pulmonary atresia and ventricular septal defect with or without systemic pulmonary collateral arteries.

Background: Pulmonary atresia and ventricular septal defect (PA-VSD), with or without systemic pulmonary collateral arteries (SPCAs), represents a complex anatomic and surgical spectrum of congenital heart disease. Currently, there is limited evidence on homograft durability after complete correction, which potentially could be affected by anatomic differences in pulmonary vasculature. Methods: This retrospective single-center study included all 69 consecutive PA-VSD patients (46 with SPCAs, 23 without SPCAs) operated on between 1978 and 2018. The primary interest was in homograft durability after complete repair. Longitudinal echocardiographic homograft function and right ventricular systolic pressure were analyzed with linear mixed-effects models. Results: The median duration of follow-up was 20 years. Of the 46 patients with SPCAs, 37 (80.4%) underwent biventricular correction at a median age of 2.7 years (interquartile range [IQR], 1.8-6.3 years). Two patients are currently awaiting unifocalization and correction. All 23 patients without SPCAs underwent successful complete correction at a median age of 1.6 years (IQR, 1.1-3.6 years). Freedom from any reintervention after 20 years was 15%. When a homograft was used during correction, freedom from homograft replacement after 20 years was comparable in the 2 groups (P = .925), at 32 ± 11% in the SPCA group and 32 ± 13% in the non-SPCA group. Indications for homograft replacement were isolated stenosis (n = 7; 46.7%), isolated regurgitation (n = 3; 20.0%), and mixed stenosis and regurgitation (n = 5; 33.3%) in the SPCA group and isolated stenosis (n = 8; 88.9%) and stenosis and regurgitation (n = 1; 11.1%) in the non-SPCA group. Peak homograft gradient was significantly (P = .0003) higher in patients without SPCA, with a comparable rate of progression in the 2 groups. However, the prevalence of severe pulmonary regurgitation (PR) was higher in patients with SPCAs, estimated at 35% at 10 years, compared with 15% in patients without SPCAs. Conclusions: Homografts used for right ventricular outflow tract reconstruction in patients with PA-VSD, either with or without SPCAs, have similar limited durability. Repeated reintervention is common, and careful follow-up with attention to severe PR is warranted.

Long-term Clinical and Echocardiographic Outcomes in Young and Middle-aged Adults Undergoing the Ross Procedure.

Importance: There is no ideal valve substitute for young adults requiring aortic valve replacement. Multicenter data supporting use of the Ross procedure with respect to long-term postoperative valve-related mortality and reintervention, as well as function of the autograft and pulmonary homograft, are needed. Objective: To determine the long-term clinical and echocardiographic outcomes in young and middle-aged patients undergoing the Ross procedure. Design, Setting, and Participants: A retrospective multicenter international cohort study with a median follow-up period of 9.2 years was conducted in 5 experienced centers regularly performing the Ross procedure. Consecutive patients aged 18 to 65 years were included by each center between 1991 and 2018. Main Outcomes and Measures: Survival and autograft-related and homograft-related reintervention. Serial echocardiographic measurements of valve function were analyzed using mixed-effects modeling. Results: During the study period, 1431 patients (74.3% men; n = 1063) were operated on at a median age of 48.5 years (mean [SD], 47.7 [9.5]; range, 18.1-65; interquartile range, 42.7-54.0). Implantation techniques were root inclusion in 355 (24.9%), root replacement in 485 (34.0%), and subcoronary implantation in 587 (41.1%). Right ventricular outflow tract reconstruction was performed with homografts in 98.6% (n = 1189) and bioprostheses in 1.4% (n = 17). Ten patients (0.7%) died before discharge. Median follow-up was 9.2 years (13 015 total patient-years). Survival after 10 and 15 years was 95.1% (95% CI, 93.8%-96.5%) and 88.5% (95% CI, 85.9%-91.1%), respectively. Freedom from autograft and homograft reintervention after 15 years was 92.0% and 97.2%, respectively. Late events were autograft endocarditis in 14 patients (0.11% per patient-year), homograft endocarditis in 11 patients (0.08% per patient-year), and stroke in 37 patients (0.3% per patient-year). Conclusions and Relevance: Given its excellent short-term and long-term outcome in young and middle-aged adults in this study, the Ross procedure should be considered in young and middle-aged adults who require aortic valve replacement. Patients should be referred to an experienced center with a program dedicated to the Ross procedure.

Timing of pulmonary valve replacement in patients with corrected Fallot to prevent QRS prolongation.

OBJECTIVES: Timing of pulmonary valve replacement (PVR) remains one of the most heavily debated topics in congenital cardiac surgery. We aimed to analyse the temporal evolution of QRS duration before and after PVR. METHODS: We included 158 consecutive patients who underwent PVR after previous correction with transannular patch. All 3549 available serial standard 12-lead surface QRS measurements of 158 (100%) patients were analysed with linear mixed-effect modelling. RESULTS: PVR was performed at a mean age of 28.0 ± 10.7 years, 23.4 ± 8.4 years after correction. Hospital survival was 98.1%. A longer time interval between ToF correction and PVR (P < 0.001), and an older age at correction (P = 0.015) were predictive of progressive QRS prolongation after PVR. Women on average had a shorter QRS duration (P = 0.005) after PVR. The model predicted that in patients corrected early (model age 0.5 years), PVR within 17 years after correction leads to narrowing or stabilization of QRS width. PVR beyond 17 years was associated with prolongation of QRS duration. In a patient corrected late (model age 5 years), PVR has to be performed within 15 years after correction to prevent prolongation. Finally, a longer time period between correction and PVR was associated with an increased hazard of cardiac death (hazard ratio 1.097, 95% confidence interval 1.002-1.200). CONCLUSIONS: Prolongation of QRS duration after PVR was associated with a longer time between correction and PVR, older age at correction and male sex. Prevention of progressive QRS prolongation by earlier PVR can potentially reduce the hazard of adverse events after PVR.

Influence of pregnancy on long-term durability of allografts in right ventricular outflow tract.

BACKGROUND: There is very limited published evidence about the influence of pregnancy on allograft durability in right ventricular outflow tract position. We present the first study using mixed and joint modeling. METHODS: This retrospective study compared clinical and valve related outcomes of all consecutive female hospital survivors in their fertile life phase (18-50 years) based on pregnancy. Serial echocardiographic measurements of pulmonary gradient and regurgitation were analyzed for their association with valve replacement using joint models for longitudinal and time-to-event data. Occurrence of first pregnancy was included as a time-dependent intermediate event in both the longitudinal and survival analyses of the joint model to assess its impact on the hemodynamic and clinical outcome. RESULTS: In total, 196 consecutive women in their fertile life-phase with an allograft were included. Complete information of 176 (90%) allografts in 165 women was available, including 1395 echocardiograms. Of these women, 51 (30.9%) women had 84 completed pregnancies at an average age of 29.1 ± 3.9 (SD) years; 8.1 ± 6.1 years since allograft implantation. Tetralogy of Fallot was the most common diagnosis in both groups. After a mean follow-up of 15.2 years (range 0.1-30), 7 (13.7%) parous women underwent valve replacement versus 20 (17.5%) nulliparous women. During this follow-up, the mean allograft gradient in parous (24.2 mm Hg) and nulliparous (21.0 mm Hg) women was comparable (P = .225). A 1-mm Hg increase in pulmonary gradient increased the instantaneous risk of pulmonary valve replacement (PVR) by a ratio of 1.051 (P < .001), regardless of pregnancy. Similarly, development of moderate or severe regurgitation increased the risk of PVR (P = .038), regardless of pregnancy. Pregnancy was not associated with a change in the allograft gradient (P = .258), regurgitation grade (P = .774), or hazard of PVR (P = .796) during follow-up. CONCLUSIONS: Pregnancy is not associated with impaired allograft durability in women with good cardiac health.

Outcome after surgical repair of tetralogy of Fallot: A systematic review and meta-analysis.

INTRODUCTION: Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease. Intracardiac correction was pioneered by Walton Lillehei in 1955 and has since then gone through major developments. The aim of this study was to provide a systematic literature review of published results on the long-term outcome of complete surgical correction of TOF. METHODS: MEDLINE, PubMed, Embase, Web of Science, Cochrane, and Google Scholar were systematically searched for literature published between January 2000 and July 2018. Pooled estimates with a random effects model after log-transformation were calculated for mortality and reintervention. Potential heterogeneity was assessed by subgroup analyses and meta-regression. RESULTS: A total of 143 papers of 137 distinct cohorts comprising 21,427 patients and total follow-up duration of 147,430 patient-years were included. Overall mean age at correction was 3.7 ± 5.6 years, but excluding papers exclusively focusing on correction in adults yielded a mean age of 0.5 ± 2.5 years at correction. Previous palliative shunts (107 studies), a transventricular approach (81 studies), and a transannular patch (124 studies) were used in 16% (range 0%-78%), 39% (range 0%-100%), and 49% (range 0%-100%) of the patients. respectively. In case a transannular patch was used, monocusp reconstruction was applied in 15% (range 0%-100%) (49 studies). The most common genetic abnormality was Down syndrome, with a pooled estimated prevalence of 4.6% (range 0%-12.3%). The pooled estimates of early and late mortality were 2.84% (95% confidence interval [CI], 2.34-3.45) and 0.42%/year (95% CI, 0.33-0.54), respectively. The pooled estimate of late cardiac mortality was 0.26%/year (95% CI, 0.21-0.34). Valve-related mortality and non-valve-related mortality had pooled estimates of 0.20%/year (95% CI, 0.15-0.26) and 0.17%/year (95% CI, 0.12-0.22), respectively. The pooled estimate of reintervention was 2.26%/year (95% CI, 1.86-2.75). CONCLUSIONS: TOF can be surgically corrected at a young age with low perioperative and long-term mortality. Life-long intensive follow-up and substantial reintervention rates characterize the clinical course.

Long-term clinical outcome and echocardiographic function of homografts in the right ventricular outflow tract†.

OBJECTIVES: Although homografts are often the preferred valve conduits for right ventricular outflow tract (RVOT) reconstruction, data on long-term homograft-related outcomes, durability and impact on quality of life (QoL) are scarce. The aim of this study was therefore to describe the long-term homograft function, clinical outcomes and QoL after RVOT reconstruction. METHODS: We performed a single-centre retrospective analysis of all consecutive patients who underwent RVOT reconstruction with a homograft. Multiple subsequent allografts in the same patients were regarded as separate subjects. Valve-related events were analysed by Kaplan-Meier and Life Table methods. Serial echocardiographic measurements were analysed with mixed effects models. In addition, QoL was repeatedly assessed and compared with a matched general population. RESULTS: In total, 701 consecutive homografts were implanted in 604 patients [59.6% males, mean age at operation 19.5 ± 15.2 (standard deviation)]. Hospital mortality was 3.3%. After 25 years follow-up, survival and freedom from valve replacement were 84 ± 4% and 56 ± 6%, respectively. Freedom from valve replacement after 15 years for patients under 1 year of age was 28 ± 14% years, for those between 1 and 18 years, 59 ± 8%, and for those older than 18 years, 82 ± 5%. The peak gradient increased predominantly in the first postoperative decade in infants and paediatric patients from 19 to 54 mmHg. In adults, the average gradient increased from 9 to 31 mmHg after 14 years. Compared to a gender- and age-matched Dutch population, patients reported lower vitality and general health but less bodily pain. Patients, in whom QoL was repeatedly assessed, reported lower scores on physical functioning and vitality after a 5-year follow-up period. However, we found no differences in any of the subscales in patients who underwent valve replacement during the 5-year interval. CONCLUSIONS: Homografts are a durable valve alternative for RVOT reconstruction; in particular, adults show extensive freedom from valve replacement and report QoL comparable with healthy subjects. An online interactive application form created by our institution can be used to assess patient outcome after RVOT reconstruction with a homograft for different patient profiles.

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.

Outcomes of Pregnancy After Right Ventricular Outflow Tract Reconstruction With an Allograft Conduit.

BACKGROUND: There is no published evidence on pregnancy after right ventricular outflow tract (RVOT) reconstruction with an allograft. OBJECTIVES: The aim of this study was to describe pregnancy outcomes in women with allografts in the RVOT position. METHODS: A retrospective cohort study of consecutive female patients who received allografts in the RVOT position was conducted. All patients between 18 and 50 years of age were screened for cardiac, obstetric, and fetal outcomes of completed (≥20 weeks' gestation) pregnancies. RESULTS: In total, 196 women met the inclusion criteria, of whom 56 had 89 completed pregnancies. Information could be retrieved in 84 cases (94.4%). Mean maternal age was 29.6 ± 4.3 years, with 80 patients (95.2%) in New York Heart Association functional class I or II. The most common diagnosis was tetralogy of Fallot. All women survived pregnancy. There were 2 cases (2.4%) of heart failure (arrhythmic and diastolic dysfunction), 1 case (1.2%) of infection (chorioamnionitis), and 3 cases (3.6%) of pre-eclampsia. No other cardiac or obstetric events were reported. All children were born alive at a median gestational age of 38.4 weeks (interquartile range: 36.9 to 39.6 weeks), with a median birthweight of 2,930 g (interquartile range: 2,535 to 3,385 g). Seventeen (20.2%) were small for gestational age, and 20 (23.8%) were premature. Neonatal death was reported in 2 children (2.5%). Preconception pulmonary regurgitation was associated with an increased probability of pre-term labor (odds ratio: 2.610; 95% confidence interval: 1.318 to 5.172). Compared with the general Dutch population, pre-term delivery (25.0% vs. 7.4%, p < 0.001) and children small for gestational age (20.2% vs. 10.0%, p = 0.002) were more common. CONCLUSIONS: Women in good cardiac health after RVOT reconstruction with allografts can safely experience pregnancy and labor. The higher incidence of pre-term delivery and children small for gestational age warrants special attention.