Evaluating the Prevalence of Cardiac Surgery-associated Acute Kidney Injury After Septal Myectomy Combined With Concomitant Procedures in Obstructive Hypertrophic Cardiomyopathy.

OBJECTIVES: Hypertrophic obstructive cardiomyopathy (HOCM) may be treated by septal myectomy. Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication, but little is known about its incidence after septal myectomy. The objectives of this work were to evaluate the prevalence of CSA-AKI after septal myectomy and identify potential perioperative and phenotype-related factors contributing to CSA-AKI. DESIGN: This was a retrospective database analysis with new data analysis. SETTING: The study occurred in a single university academic expertise center for septal myectomy HOCM patients. PARTICIPANTS: Data from 238 HOCM patients with septal myectomy operated on between 2005 and 2022 were collected. INTERVENTIONS: CSA-AKI was stratified according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines using measurement of creatinine and urine production. Important HOCM phenotype-related and perioperative factors were analyzed for their possible associations with CSA-AKI. MEASUREMENTS AND MAIN RESULTS: CSA-AKI occurred in 45% of patients; of these, 55% were classified as KDIGO stage I and the remaining 45% as stage II, with no chronic kidney damage observed. Moreover, there were no phenotypical or perioperative characteristics that were more prevalent in the CSA-AKI cohort. However, the use of beta-blockers and coronary artery disease were more prevalent in the CSA-AKI cohort. CONCLUSIONS: CSA-AKI is a common complication after septal myectomy but was transient, and kidney function recovered in all patients.

Biatrial arrhythmogenic substrate in patients with hypertrophic obstructive cardiomyopathy.

BACKGROUND: Atrial fibrillation (AF) in patients with hypertrophic obstructive cardiomyopathy (HOCM) may be caused by a primary atrial myopathy. Whether HOCM-related atrial myopathy affects mainly electrophysiological properties of the left atrium (LA) or also the right atrium (RA) has never been investigated. OBJECTIVE: The purpose of this study was to characterize atrial conduction and explore differences in the prevalence of conduction disorders, potential fractionation, and low-voltage areas (LVAs) between the RA and LA during sinus rhythm (SR) as indicators of potential arrhythmogenic areas. METHODS: Intraoperative epicardial mapping of both atria during SR was performed in 15 HOCM patients (age 50 ± 12 years). Conduction delay (CD) and conductin block (CB), unipolar potential characteristics (voltages, fractionation), and LVA were quantified. RESULTS: Conduction disorders and LVA were found scattered throughout both atria in all patients and did not differ between the RA and LA (CD: 2.9% [1.9%-3.6%] vs 2.6% [2.1%-6.4%], P = .541; CB: 1.7% [0.9%-3.1%] vs 1.5% [0.5%-2.8%], P = .600; LVA: 4.7% [1.6%-7.7%] vs 2.9% [2.1%-7.1%], P = .793). Compared to the RA, unipolar voltages of single potentials (SPs) and fractionated potentials (FPs) were higher in the LA (SP: P75 7.3 mV vs 10.9 mV; FP: P75 2.0 mV vs 3.7 mV). FP contained low-voltage components in only 18% of all LA sites compared to 36% of all RA sites. CONCLUSION: In patients with HOCM, conduction disorders, LVA, and FP are equally present in both atria, supporting the hypothesis of a primary atrial myopathy. Conceptually, the presence of a biatrial substrate and high-voltage FP may contribute to failure of ablative therapy of atrial tachyarrhythmias in this population.

Biomechanical response of ultrathin slices of hypertrophic cardiomyopathy tissue to myosin modulator mavacamten.

Hypertrophic cardiomyopathy (HCM) is the most common inherited myocardial disorder of the heart, but effective treatment options remain limited. Mavacamten, a direct myosin modulator, has been presented as novel pharmacological therapy for HCM. The aim of this study was to analyze the biomechanical response of HCM tissue to Mavacamten using living myocardial slices (LMS). LMS (n = 58) from patients with HCM (n = 10) were cultured under electromechanical stimulation, and Verapamil and Mavacamten were administered on consecutive days to evaluate their effects on cardiac biomechanics. Mavacamten and Verapamil reduced contractile force and dF/dt and increased time-to-relaxation in a similar manner. Yet, the time-to-peak of the cardiac contraction was prolonged after administration of Mavacamten (221.0 ms (208.8 - 236.3) vs. 237.7 (221.0 - 254.7), p = 0.004). In addition, Mavacamten prolonged the functional refractory period (FRP) (330 ms (304 - 351) vs. 355 ms (313 - 370), p = 0.023) and better preserved twitch force with increasing stimulation frequencies, compared to Verapamil. As such, Mavacamten reduced (hyper-)contractility and prolonged contraction duration of HCM LMS, suggesting a reduction in cardiac wall stress. Also, Mavacamten might protect against the development of ventricular tachyarrhythmias due to prolongation of the FRP, and improve toleration of tachycardia due to better preservation of twitch force at tachycardiac stimulation frequencies.

In-vivo Sino-Atrial Node Mapping in Children and Adults With Congenital Heart Disease.

Background: Sinus node dysfunction (SND) and atrial tachyarrhythmias frequently co-exist in the aging patient with congenital heart disease (CHD), even after surgical correction early in life. We examined differences in electrophysiological properties of the sino-atrial node (SAN) area between pediatric and adult patients with CHD. Methods: Epicardial mapping of the SAN was performed during sinus rhythm in 12 pediatric (0.6 [0.4-2.4] years) and 15 adult (47 [40-55] years) patients. Unipolar potentials were classified as single-, short or long double- and fractionated potentials. Unipolar voltage, relative R-to-S-amplitude ratio and duration of all potentials was calculated. Conduction velocity (CV) and the amount of conduction block (CB) was calculated. Results: SAN activity in pediatric patients was solely observed near the junction of the superior caval vein and the right atrium, while in adults SAN activity was observed even up to the middle part of the right atrium. Compared to pediatric patients, the SAN region of adults was characterized by lower CV, lower voltages, more CB and a higher degree of fractionation. At the earliest site of activation, single potentials from pediatrics consisted of broad monophasic S-waves with high amplitudes, while adults had smaller rS-potentials with longer duration which were more often fractionated. Conclusions: Compared to pediatric patients, adults with uncorrected CHD have more inhomogeneous conduction and variations in preferential SAN exit site, which are presumable caused by aging related remodeling. Long-term follow-up of these patients is essential to demonstrate whether these changes are related to development of SND and also atrial tachyarrhythmias early in life.

Impact of sex on timing and clinical outcome of septal myectomy for obstructive hypertrophic cardiomyopathy.

BACKGROUND: Sex disparities are common in hypertrophic cardiomyopathy (HCM). Previous research has shown that at time of myectomy, women are older, have greater impairment of diastolic function and more advanced cardiac remodeling. The clinical impact of these differences is unknown. METHOD: This study included 162 HCM patients (61% men) who underwent septal myectomy. Time to treatment was calculated in relation to symptom onset and diagnosis. Pre- and post-operative echocardiographic data were collected. Sex differences were assessed at baseline and in time-to-event survival analyses for the composite endpoint of all-cause mortality, cardiac transplantation, re-intervention and aborted sudden cardiac death. RESULTS: Women were generally older at time of myectomy (57 vs. 49 years, p < 0.01), with similar time to treatment as measured from symptom onset (2.3 [1.3-6.0] vs. 2.8 [1.1-5.3] years, p > 0.05), but a shorter time since diagnosis compared to men (2.6 [1.2-7.0] vs. 4.3 [2.4-8.3] years, p = 0.02). Mean wall thickness and left atrial diameter were the same for men and women, but were higher in women when correcting for body surface area (absolute: 20 vs. 19 mm, 48 vs 46 mm, p ≥ 0.05; corrected: 9.7 vs. 11.2 mm/m2, 23.4 vs. 26.3 mm/m2, p < 0.01). After 5.9 [3.0-9.1] years, 15% of men and 8% of women had reached the composite endpoint (p > 0.05). CONCLUSION: In conclusion, although women present later in life and seem to have more advanced disease on echocardiography, time until myectomy was similar and clinical outcomes after myectomy are favourable for both men and women.

Early and late post-operative arrhythmias after surgical myectomy: 45 years of follow-up.

AIMS: The aims of this study are to investigate the incidence and determinants of post-operative atrial arrhythmias, conduction disorders and mortality in hypertrophic obstructive cardiomyopathy (HOCM) patients undergoing transaortic myectomy. METHODS AND RESULTS: This retrospective single-center study was conducted in 249 patients (median age 54 years [40-64], 42% female) undergoing transaortic myectomy. Post-operative atrial fibrillation (AF) was reported in 84 patients (33.7%), including 56 patients (22.5%) with de novo AF. Older age (HR = 1.027 (1.003-1.052), p = 0.029) and hypercholesterolemia (HR = 2.296 (1.091-4.832) p = 0.029) were independent predictors for de novo post-operative AF. Late post-operative AF and atrial flutter (AFL) occurred in 18.9% and 6.8% of the patients, respectively. De novo early post-operative AF increased the risk of late post-operative AF (HR = 3.138 (1.450-6.789), p = 0.004). Patients with a right bundle branch block had a higher risk of early-postoperative pacemaker implantation (p = 0.003, HR = 9.771 (2.195-43.505)). Higher age at time of surgery (HR = 1.053 (1.026-1.081), p < 0.001) was a predictor for late mortality (n = 47, 18.9%). CONCLUSION: Early and late post-operative AF, AFL and other SVTs are common sequelae after myectomy and are associated with older age at surgery, history of AF and early post-operative AF. Early post-operative arrhythmias are not transient and periodic rhythm monitoring is therefore essential to initiate therapy as soon as possible.

Rapid method for intraoperative assessment of aortic coarctation using three-dimensional echocardiography.

AIMS: The availability of three-dimensional (3D) echography with its multiplanar review analysis software on board now allows detailed examination in assessing morphological details. We evaluated the feasibility of 3D echography in assessing intraoperative morphological details of aortic coarctation (CoA) and its repair. METHODS AND RESULTS: Nine consecutive children scheduled for surgery of CoA were intraoperatively evaluated. Intraoperative 3D data sets were taken and analysed online before resection of the coarctation, showing the cross-sectional area (CSA) of the proximal aorta, coarctation, and the distal descending aorta. After resection of the coarctation and extended end-to-end anastomosis, a 3D data set was recorded to analyse the CSA of the anastomosis. In nine out of nine consecutive procedures, intraoperative 3D echography permitted comprehensive viewing and measuring of CoA and its repair. In three out of nine surgical procedures, intraoperative 3D echography provided additional information to support surgical decision-making. CONCLUSION: Intraoperative 3D echography is a feasible non-invasive imaging modality for intraoperative assessment of CoA and its repair, which provides useful additional information.

Alveolar recruitment strategy and PEEP improve oxygenation, dynamic compliance of respiratory system and end-expiratory lung volume in pediatric patients undergoing cardiac surgery for congenital heart disease.

OBJECTIVE: Optimizing alveolar recruitment by alveolar recruitment strategy (ARS) and maintaining lung volume with adequate positive end-expiratory pressure (PEEP) allow preventing ventilator-induced lung injury (VILI). Knowing that PEEP has its most beneficial effects when dynamic compliance of respiratory system (Crs) is maximized, we hypothesize that the use of 8 cm H(2)O PEEP with ARS results in an increase in Crs and end-expiratory lung volume (EELV) compared to 8 cm H(2)O PEEP without ARS and to zero PEEP in pediatric patients undergoing cardiac surgery for congenital heart disease. METHODS: Twenty consecutive children were studied. Three different ventilation strategies were applied to each patient in the following order: 0 cm H(2)O PEEP, 8 cm H(2)O PEEP without an ARS, and 8 cm H(2)O PEEP with a standardized ARS. At the end of each ventilation strategy, Crs, EELV, and arterial blood gases were measured. RESULTS: EELV, Crs, and P(a)O(2)/FiO(2) ratio changed significantly (P < 0.001) with the application of 8 cm H2O + ARS. Mean P(a)CO(2)- PETCO(2) difference between 0 PEEP and 8 cm H2O PEEP + ARS was also significant (P < 0.05). CONCLUSION: An alveolar recruitment strategy with relative high PEEP significantly improves Crs, oxygenation, P(a)CO(2)- PETCO(2) difference, and EELV in pediatric patients undergoing cardiac surgery for congenital heart disease.

Tetralogy of Fallot in the Current Era.

Only few studies have reported long-term outcome of the transatrial-transpulmonary approach in the current era of management of tetralogy of Fallot (ToF). We investigated 15-year outcome of correction via a transatrial-transpulmonary approach in a large cohort of successive patients operated in the 21st century. All infant ToF patients undergoing transatrial-transpulmonary ToF correction between 2000 and 2015 were included (N = 177, 106 male, median follow-up 7.1 (interquartile range 3.0-10.9) years. Data regarding postoperative complications, reinterventions, development of atrial and ventricular arrhythmia, cardiac function, and survival were evaluated. Prior shunting was performed in 10 patients (6%). The transatrial-transpulmonary approach resulted in valve-sparing surgery in 57 patients (32%). Postoperative surgical complications included junctional ectopic tachycardia (N = 12, 7%), pericardial (N = 10, 6%) or pleural effusion (N = 7, 3%), chylothorax (N = 7, 4%), bleeding requiring reoperation (N = 4, 3%), and superficial wound infection (N = 1). Fifty-one patients underwent 68 reinterventions, mainly due to pulmonary restenosis (PS) (N = 57). ToF correction at age <2 months and double outlet or double-chambered right ventricle variants of the ToF spectrum were independent predictors for reintervention. Patients undergoing valve-sparing ToF correction had a significant longer PR-free survival than those with a transannular patch (8.5 [95% confidence interval 6.8-10.3] years vs 1.1 [95% confidence interval 0.8-1.5] years; P < 0.001). Overall mortality was 2.8%; mortality rates were higher in premature/dysmature newborns (0.7% vs 9.5%; P < 0.001). Although the 15-year outcome of the transatrial-transpulmonary approach in terms of postoperative complications and mortality rates is excellent, the high incidence of moderate and severe PR is worrisome. Valve-sparing surgery was associated with a substantially lower incidence of PR, yet was surgically not possible in the majority of patients.

Protein Quality Control Activation and Microtubule Remodeling in Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disorder. It is mainly caused by mutations in genes encoding sarcomere proteins. Mutant forms of these highly abundant proteins likely stress the protein quality control (PQC) system of cardiomyocytes. The PQC system, together with a functional microtubule network, maintains proteostasis. We compared left ventricular (LV) tissue of nine donors (controls) with 38 sarcomere mutation-positive (HCMSMP) and 14 sarcomere mutation-negative (HCMSMN) patients to define HCM and mutation-specific changes in PQC. Mutations in HCMSMP result in poison polypeptides or reduced protein levels (haploinsufficiency, HI). The main findings were 1) several key PQC players were more abundant in HCM compared to controls, 2) after correction for sex and age, stabilizing heat shock protein (HSP)B1, and refolding, HSPD1 and HSPA2 were increased in HCMSMP compared to controls, 3) α-tubulin and acetylated α-tubulin levels were higher in HCM compared to controls, especially in HCMHI, 4) myosin-binding protein-C (cMyBP-C) levels were inversely correlated with α-tubulin, and 5) α-tubulin levels correlated with acetylated α-tubulin and HSPs. Overall, carrying a mutation affects PQC and α-tubulin acetylation. The haploinsufficiency of cMyBP-C may trigger HSPs and α-tubulin acetylation. Our study indicates that proliferation of the microtubular network may represent a novel pathomechanism in cMyBP-C haploinsufficiency-mediated HCM.

Intraoperative cell salvage in infants undergoing elective cardiac surgery: a prospective trial.

BACKGROUND: For a long time intraoperative cell salvage was considered not to be applicable in paediatric patients due to technical limitations. Recently, new autotransfusion devices with small volume centrifugal bowls and dedicated paediatric systems allow efficient blood salvage in small children. The purpose of this prospective non-randomised study was to determine the impact of intraoperative cell salvage on postoperative allogeneic blood products transfusion in infant patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS: Two consecutive cohorts (122 patients) were studied. The first cohort underwent procedures between January 2004 and July 2005 with only blood salvage from the residual volume. The second cohort consisted of patients operated on from August 2005 to December 2006, with additional use of intraoperative cell salvage. The following variables were analysed: peri- and postoperative blood loss, transfusion of homologous blood products and cell salvage product, haematological and coagulation data, measured before, during and after the operation. RESULTS: Additional intraoperative cell salvage significantly enhanced the amount of cell saving product available for transfusion (183+/-56 ml vs 152+/-57 ml, p=0.003) and significantly more patients in this group received the cell saving product postoperatively. Consequently, allogeneic blood transfusion was significantly reduced in volume as well as in frequency. We did not observe any adverse effects of intraoperative cell salvage. CONCLUSION: Intraoperative cell salvage, employed as an adjuvant technique to the residual volume salvage in infants undergoing first time cardiac surgery with cardiopulmonary bypass, was a safe and effective method to reduce postoperative allogeneic blood transfusion. Considering current cell salvage related expense and the cost reduction achieved by diminished allogeneic transfusion, intraoperative cell salvage in infants demonstrated no economic benefit.

Long-term follow-up after repair of Ebstein's anomaly.

OBJECTIVE: We studied the long-term results of vertical plication repair of Ebstein's anomaly according to Carpentier. METHODS: Between 1988 and 2007, 28 patients (mean age 28.8+/-15.7 years, range 4-58 years) underwent vertical plication repair of Ebstein's anomaly. At operation the anomaly was classified according to Carpentier. In three patients (11%) a cavopulmonary shunt was added at the repair on the indication of impaired right ventricular function. RESULTS: There was no operative mortality. Early mortality was 3.6% (one patient). Actuarial survival and actuarial freedom from reoperation at 19 years were 96% (95% CI; 96-97%) and 72% (95% CI; 53-92%), respectively. Six patients required reoperation, with a successful re-repair in three patients. Mean duration of follow-up was 10.7+/-6.5 years. One year postoperatively, tricuspid incompetence had decreased significantly (p<0.001), as had New York Heart Association (NYHA) functional class (p<0.001). In addition, exercise tolerance had increased (70+/-19% to 92+/-9% of predicted values, p<0.05). Both tricuspid function and NYHA functional class remained essentially unchanged at the end of follow-up, indicating durable haemodynamic and functional results. CONCLUSION: This study demonstrates favourable long-term results following vertical plication repair of Ebstein's anomaly with low mortality, acceptable morbidity and good haemodynamic and functional results.

Usefulness of intraoperative real-time 3D transesophageal echocardiography in cardiac surgery.

BACKGROUND: Recent advances in three-dimensional (3D) echocardiography allow to obtain real-time 3D transesophageal (RT3DTEE) images intraoperatively. METHODS: Preoperative transthoracic echocardiography (TTE) revealed: hypertrophic ventricular septum (TTE:19.3 mm), systolic anterior motion (SAM) not causing obstruction and malcoaptation of the anterior mitral valve leaflet (AMVL), and posterior mitral valve leaflet (PMVL) with severe mitral regurgitation. RESULTS: Intraoperative TEE with a x7-2t MATRIX-array transducer (Philips, Andover, MA, USA) with a transducer frequency of x7-2 t mHz, connected to a iE33 (Philips), shows us that the main mechanism and site of regurgitation was an AMVL cleft. We also measured a 24.3-mm thickness of the ventricular septum and analyzing the 3D full volume acquisition revealed that there was no SAM. CONCLUSION: Intraoperative RT3DTEE permitted comprehensive 3D viewing of the mitral valve revealing the mechanism of mitral valve regurgitation, SAM, and the exact width of the hypertrophic ventricular septum.

Surgical correction of a coronary fistula between the left main coronary artery and the coronary sinus in a neonate.

We present a rare case of a 6-day old female neonate with a particularly exceptional coronary anatomy encompassing a fistula between the left main coronary artery and the coronary sinus with steal phenomenon, mandating surgical correction. The condition is extremely rare with an estimated incidence of about 0.1-0.2%. We operated this girl early on to prevent ischaemic events and pulmonary overflow with future heart failure. Further, we discuss possible aetiology and pathophysiological mechanisms of coronary artery fistulae and steal phenomena. Depending on specific anatomic characteristics, an interventional approach may be an alternative for surgical closure; however, this was not possible in our case.

Outcome after aortic valve replacement in children: A systematic review and meta-analysis.

OBJECTIVE: Despite an increasing interest in pediatric aortic valve repair, aortic valve replacement in children may be unavoidable. The evidence on outcome after pediatric aortic valve replacement is limited and usually reported in small case series. This systematic review and meta-analysis aims to provide an overview of reported outcome of pediatric patients after aortic valve replacement. METHODS: A systematic literature search for publications reporting outcome after pediatric aortic valve replacement published between January 1990 and May 2015 was conducted. Studies written in English with a study size of more than 30 patients were included. RESULTS: Thirty-four publications reporting on 42 cohorts were included in this review: 26 concerning the Ross procedure (n = 2409), 13 concerning mechanical prosthesis aortic valve replacement (n = 696), and 3 concerning homograft aortic valve replacement (n = 224). There were no studies on bioprostheses that met our inclusion criteria. The pooled mean patient age was 9.4 years, 12.8 years, and 8.9 years for Ross, mechanical prosthesis, and homograft recipients, respectively. Pooled mean follow-up was 6.6 years. The Ross procedure was associated with lower early (4.20%; 95% confidence interval [CI], 3.37-5.22 vs 7.34%; 95% CI, 5.21-10.34 vs 12.82%; 95% CI, 8.91-18.46) and late mortality (0.64%/y; 95% CI, 0.49-0.84 vs 1.23%/y; 95% CI, 0.85-1.79 vs 1.59%/y; 95% CI, 1.03-2.46) compared with mechanical prosthesis aortic valve replacement and homograft aortic valve replacement, respectively. No significantly different aortic valve reoperation rates were observed between the Ross procedure and mechanical prosthesis aortic valve replacement (1.60%/y; 95% CI, 1.27-2.02 vs 1.07%/y; 95% CI, 0.68-1.68, respectively), whereas homograft aortic valve replacement was associated with significantly higher aortic valve reoperation rates (5.44%/y; 95% CI, 4.24-6.98). The Ross procedure-associated right ventricular outflow tract reoperation rate was 1.91% per year (95% CI, 1.50-2.44). CONCLUSIONS: This systematic review illustrates that all currently available aortic valve substitutes are associated with suboptimal results in children, reflecting the urgent need for reliable and durable repair techniques and innovative replacement solutions for this challenging group of patients.

Long-term benefit of myectomy and anterior mitral leaflet extension in obstructive hypertrophic cardiomyopathy.

Severely symptomatic patients with obstructive hypertrophic cardiomyopathy (HC) may benefit from surgical myectomy. In patients with enlarged mitral leaflets and mitral regurgitation, myectomy can be combined with anterior mitral leaflet extension (AMLE) to stiffen the midsegment of the leaflet. The aim of this study was to evaluate the long-term results of myectomy combined with AMLE in patients with obstructive HC. This prospective, observational, single-center cohort study included 98 patients (49 ± 14 years, 37% female) who underwent myectomy combined with AMLE from 1991 to 2012. End points included all-cause mortality and change in clinical and echocardiographic characteristics. Mortality was compared with age- and gender-matched patients with nonobstructive HC and subjects from the general population. Long-term follow-up was 8.3 ± 6.1 years. There was no operative mortality, and New York Heart Association class was reduced from 2.8 ± 0.5 to 1.3 ± 0.5 (p <0.001), left ventricular outflow tract gradient from 93 ± 25 to 9 ± 8 mm Hg (p <0.001), mitral valve regurgitation from grade 2.0 ± 0.9 to 0.5 ± 0.8 (p <0.001), and systolic anterior motion of the mitral valve from grade 2.4 ± 0.9 to 0.1 ± 0.3 (p <0.001). The 1-, 5-, 10-, and 15-year cumulative survival rates were 98%, 92%, 86%, and 83%, respectively, and did not differ from the general population (99%, 97%, 92%, and 85%, respectively, p = 0.3) or patients with nonobstructive HC (98%, 97%, 88%, and 83%, respectively, p = 0.8). In conclusion, in selected patients with obstructive HC, myectomy combined with AMLE is a low-risk surgical procedure. It results in long-term symptom relief and survival similar to the general population.

Assessment of right ventricular fibrosis in different forms of pulmonary atresia with ventricular septal defect.

BACKGROUND: In pulmonary atresia with ventricular septal defect (PA-VSD), the corrective surgical strategy aims to reduce the right ventricular (RV) overload and restore physiological pulmonary perfusion before the characteristic RV hypertrophy and fibrosis become irreversible. OBJECTIVE: To assess RV fibrosis in different forms of PA-VSD. METHODS: RV biopsies were obtained at corrective surgery from PA-VSD patients (n=14, mean age 2.5+/-1.2 years) with patent arterial duct (PAD group, n=6; mean age 1.7+/-0.5 years) or systemic-pulmonary collateral arteries (SPCA group, n=8; mean age 3.2+/-1.2 years) and from age-matched controls (control group, n=6; mean age 2.5+/-1.8 years). Myocardial expression patterns (messenger RNA [mRNA] and protein levels) of the extracellular matrix proteins (eg, fibronectin and collagens [subtype I alpha and III) were quantitatively analyzed in relation to myocardial cell hypertrophy. RESULTS: Comparing the age of PA-VSD patients at surgery, the SPCA group was older than the PAD group (P=0.01). Expression analysis by reverse transcriptase polymerase chain reaction showed significantly higher mRNA levels in patients with PA-VSD for collagen III (PA-VSD versus controls; 0.9+/-0.2 versus 0.6+/-0.1, P=0.03) than in controls, whereas collagen I alpha and fibronectin mRNA levels did not differ. No differences were found between the PAD and SPCA groups. The myocyte cross sectional surface area showed enhanced myocyte hypertrophy in patients with PA-VSD compared with the control group (P=0.015), with no significant difference between the PAD and SPCA groups. Video image analysis of immunohistochemical staining corrected for hypertrophy revealed unchanged interstitial collagens and fibronectin levels in all groups. However, perivascular staining corrected for the vessel lumen area showed significantly lower total collagen levels in patients with PA-VSD than in the control group (3.2+/-1.2 versus 7.2+/-2.8, respectively; P=0.004). CONCLUSIONS: The results indicate that the extracellular matrix support for the coronary blood vessels appears to be suboptimal in patients with PA-VSD. The staged surgical approach in the SPCA group (with a higher age at correction) did not result in an excessive accumulation of fibrosis markers in the RV myocardium.

Carcinoid heart disease: outcomes after surgical valve replacement.

OBJECTIVES: To describe the early and late outcomes of carcinoid patients undergoing surgical heart valve replacement. METHODS: In a retrospective study, records of patients with symptomatic carcinoid heart disease referred for valve surgery between 1993 and 2010 at two academic centres were reviewed. The perioperative and postoperative outcomes were analysed. RESULTS: Nineteen patients, with a mean age of 56 ± 9.6 years, underwent cardiac surgery for carcinoid syndrome. Sixteen patients underwent implantation of one or more mechanical bileaflet valve prosthesis and three patients had one or more bioprosthetic valves implanted. Survival after 1 and 5 years was 71 and 43%, respectively. Six out of nine survivors were at last follow-up in New York Heart Association class I. Valve-related events such as valve thrombosis or bleeding complications were not registered. Echocardiography showed improvement of right ventricular dilatation in 80% of patients. CONCLUSIONS: Despite advanced cardiac morbidity at the time of operation, early postoperative survival was 90%. Long-term survival of patients with carcinoid heart disease undergoing valve replacement is determined by carcinoid progression. The surviving patients had a persistent improvement in functional capacity without valve-related complications of the mechanical prosthesis.

Relevance of colloid oncotic pressure regulation during neonatal and infant cardiopulmonary bypass: a prospective randomized study.

OBJECTIVE: In neonatal and infant cardiac surgery with cardiopulmonary bypass (CPB), hemodilution with reduction of plasma albumin concentration and low colloid oncotic pressure (COP) are the main factors associated with tissue edema and postoperative weight gain. The aim of our study was to evaluate the influence of two different COP regulatory strategies on post-bypass body weight gain, fluid balance, and clinical outcomes. METHODS: Seventy elective patients with body weight<10 kg underwent first-time cardiac surgery with CPB and were randomized into two groups. The standard COP group received 0.5 g kg(-1) of human albumin in the priming and, during CPB, albumin was added to maintain the COP>15 mmHg. In the high COP group, albumin concentration in the priming was 5% and, during CPB, the COP was maintained above 18 mmHg. All patients were monitored before, during and until 24h postoperatively. Data were collected on body weight gain, COP, albumin concentration, fluids transfusion, blood loss, urine production and laboratory results. RESULTS: Patients' demographics and operative data were comparable. Although the high COP group had perioperatively significantly higher COP and albumin concentration than the standard COP group, no significant difference was found in the body weight gain. There were also no significant differences between the groups with respect to fluid balance, urine output and blood loss. However, the high COP group had significantly shorter postoperative duration of mechanical ventilation (10h vs 14 h, p=0.02) and lower plasma lactate concentration post operation (1.1 mmoll(-1) vs 1.4 mmoll(-1), p=0.046). CONCLUSIONS: The COP regulatory strategy for neonatal and infant CPB, based upon the 5% concentration of albumin in the priming and a COP target of 18 mmHg during bypass, better preserves the plasma albumin concentration within the physiological range and stabilizes the colloid pressure than the standard strategy (0.5 gkg(-1) albumin in the priming and bypass COP target at 15 mmHg). Nevertheless, only the lower postoperative plasma lactate concentration and the shorter duration of mechanical ventilation in the high COP group indicated the potential clinical benefit of this new strategy.

Clinical outcome and health-related quality of life after right-ventricular-outflow-tract reconstruction with an allograft conduit.

OBJECTIVE: Allograft conduits are used for reconstruction of the right ventricular outflow tract in congenital heart malformations (biventricular repair) and autograft procedures. A retrospective evaluation of allograft reconstruction of the right-ventricular-outflow-tract reconstruction was conducted and a cross-sectional quality of life study was performed. METHODS: Between August 1986 and March 2009, 509 allografts (435 pulmonary and 74 aortic) were implanted in 463 pediatric and adult patients (308 right-sided congenital heart malformations and 155 autograft procedures). Perioperative and follow-up data were collected and analyzed. Kaplan-Meier analyses were done for survival, valve-related re-operation, and valve-related events. Cox regression analysis was used for evaluation of potential risk factors. In addition, the Short Form-36 was presented to patients to assess the perceived quality of life. The results of the Short Form-36 were compared to age-adjusted Dutch population norms. RESULTS: The mean age at allograft implantation was 19 years (1 week-66 years). Mean follow-up was 9 years (2 days-22 years). Forty-eight patients died during follow-up. Patient survival was 93% at 10 years and 88% at 15 years. A total of 63 re-operations were required for allograft dysfunction in 58 patients. Freedom from valve-related re-operation was 89% at 10 years and 81% at 15 years. Freedom from valve-related events was 86% at 10 years and 74% at 15 years. Younger patient age (p=0.007) and the use of an aortic allograft (p<0.001) were identified as independent risk factors for allograft re-operation. Patients between 14 and 40 years scored significantly lower on 'physical functioning' and 'general health' subscales than the general Dutch population, but scored better on the subscales 'emotional role functioning' and 'bodily pain'. Except for the subscale 'general health', on which patients within our study population scored lower, patients between 41 and 60 years had comparable average scores as the general Dutch population. The older patient group (61 years or older) had a better average score on the subscale 'bodily pain' and similar scores on other subscales with respect to the general Dutch population. CONCLUSIONS: Right-ventricular-outflow-tract reconstruction with an allograft conduit can be performed with good patient survival, acceptable long-term allograft durability, and good perceived quality of life.