Analysis of 14,843 Neonatal Congenital Heart Surgical Procedures in the Euroean Association for Cardiothoracic Surgery Congenital Database Andrzej Kansy, MD, PhD, Zdzislaw Tobota, MD, Przemyslaw Maruszewski, MD, and Bohdan Maruszewski, MD, PhD Deartment of Cardiothoracic Surgery, Children s Memorial Health Institute, Warsaw, Poland Background. Early outcomes of congenital heart surgery in neonates have significantly imroved during the last decade. Further imrovements require identification of secific risk factors correlating with early mortality and morbidity. Methods. Between January 1999 and May 2008 data on 14,843 congenital heart rocedures erformed in 118 congenital heart surgery centers in 34 countries were submitted to the Euroean Association for Cardiothoracic Surgery Congenital Database. Mean age at surgery was 11.8 days and mean body weight was 2.9 kg. Multivariate stewise regression analysis was used to assess the risk factors for ostoerative comlications and death. Results. Thirty-day mortality of 9.1% was significantly different from hosital mortality (10.7%). Postoerative comlications occurred in 29.2% of neonates. In multivariate analysis, early death rate was statistically significantly modified by body weight, Aristotle basic score (ABS), cardioulmonary byass time (CPB time), aortic cross-clam time, circulatory arrest time, and univentricular hysiology. The rate of comlications was associated with ABS, CPB time, and circulatory arrest time. Conclusions. In neonatal congenital heart surgery significant risk of early death extends beyond 30 ostoerative days. Multivariate analysis confirmed that lower body weight, higher ABS, longer CPB time, longer aortic cross-clam time, longer circulatory arrest time, and univentricular hysiology are risk factors for hosital mortality. Higher ABS as well as longer CPB time and circulatory arrest time are associated with the rate of comlications. (Ann Thorac Surg 2010;89:1255 9) 2010 by The Society of Thoracic Surgeons Defects of the cardiovascular system are among the most commonly reorted congenital defects, with an incidence of 6 in 1,000 live births [1]. Imrovement in oerative techniques allows to erform more comlex cardiac surgery in neonates (age between 1 and 30 days), including those with low body weight. The early outcomes of congenital heart surgery in neonates have also significantly imroved during the last decade [2]. The number of studies reorting surgical outcomes and risk factors in neonates are limited. In 2008, in the Society of Thoracic Surgeons (STS) Congenital Heart Database, Curzon and colleagues [3] found a correlation between body weight below 2.5 kg and increased risk of mortality in several congenital heart surgery neonatal rocedures. Further imrovement requires identification of secific risk factors associated with unsatisfactory results of surgical treatment. To define the risk factors correlating with early mortality and morbidity we have studied the data collected in the Euroean Association for Cardiothoracic Acceted for ublication Jan 4, 2010. Presented at the Poster Session of the Forty-fifth Annual Meeting of The Society of Thoracic Surgeons, San Francisco, CA, Jan 26 28, 2009. Address corresondence to Dr Kansy, Children s Memorial Health Institute, Al. Dzieci Polskich 20, 04-830 Warsaw, Poland; e-mail: ankansy@ w.l. Surgery (EACTS) Congenital Database between 1999 and 2008. Patients and Methods The study was carried out according to the EACTS Congenital Database olicy (www.eactscongenitaldb.org, aragrah 2). Because the individual atients were not identified the need for arental consent was waived. The study was acceted by the EACTS Database Director according to the olicy (aragrah 6). Database The EACTS Congenital Database collects rocedurerelated data on atients undergoing surgery for congenital heart defects. The EACTS Congenital Database, established by the EACTS in 1999 sonsored by the EACTS and Euroean Congenital Heart Surgeons Association since, is a result of transformation of the Euroean Congenital Heart Defects Database created by the Euroean Congenital Heart Surgeons Association in 1992. Data collected in the database include basic demograhic information, anatomic diagnosis, associated noncardiac abnormalities, reoerative risk factors, intraoerative data, tye of surgical rocedure, and ostoerative comlica- 2010 by The Society of Thoracic Surgeons 0003-4975/10/$36.00 Published by Elsevier Inc doi:10.1016/j.athoracsur.2010.01.003
1256 KANSY ET AL Ann Thorac Surg OUTCOMES OF NEONATAL CARDIAC SURGERY 2010;89:1255 9 Abbreviations and Acronyms ABS Aristotle Basic Score AoX aortic cross-clam ASO arterial switch oeration ASO VSD arterial switch oerations ventricular setal defect closure B-T shunt Blalock-Taussig shunt CoA reair coarctation of the aorta reair EACTS Euroean Association for Cardiothoracic Surgery IAA interruted aortic arch IAA reair interruted aortic arch reair PDA atent ductus arteriosus STS Society of Thoracic Surgeons TAPVC total anomalous ulmonary vein connection TGA transosition of the great arteries TGA VSD transosition of the great arteries ventricular setal defect tions, as well as hosital and 30-day mortality [2]. The database is entirely anonymous regarding atient, hosital, and surgeons sensitive information. Thirty-day mortality is defined as any death occurring within 30 days after surgery, regardless of cause, or whether in or out of the hosital [4]. Hosital mortality is defined as any death occurring in the hosital regardless of the cause and time from surgery during the same admission. These definitions are used by both the EACTS and STS Congenital Databases together with the same list of diagnoses, rocedures, and comlications [5]. Study Poulation The study included data on 14,843 congenital heart rocedures erformed in 12,738 neonates between January 1999 and May 2008. The data have been submitted from 118 congenital heart surgery centers in 34 countries. All data were internally validated by an integrated software module that rejects all records that do not meet given criteria and sends this data back for correction. A total of 12.1% of data were additionally verified using on-site Table 1. Most Common Surgical Procedures Procedure n Mortality % ASO 2,154 5.99 CoA reair 2,012 4.63 PDA surgical closure 1,829 5.80 B-T shunt 1,501 12.0 Norwood rocedure 1,216 36.2 ASO VSD 657 9.55 TAPVC reair 426 16.5 IAA reair 283 19.2 ASO arterial switch oeration; B-T Blalock-Taussig; CoA coarctation of the aorta; IAA interruted aortic arch; PDA atent ductus arteriosus; TAPVC Total anomalous ulmonary vein connection; VSD ventricular setal defect. Table 2. Patients back-to-back data verification rotocol. The database staff visited the sites and checked the accuracy of 100% of the records for the fields undergoing verification. In the second hase the central database rintouts were comared with the local data source [6] (Table 1). Mean age for all rocedures was 11.8 days (95% confidence interval [CI] 11.7 to 11.9) 7.5, with mean body weight of 2.9 kg, ( 2.89 to 2.93) 0.87 and Aristotle Basic Score 7.57, ( 7.51 to 7.63) 3.5. Among 14,843 rocedures there were 47.6% (7,074) of cardioulmonary byass (CPB) rocedures and 52.4% (7,718) of non-cpb rocedures. A total of 2,707 (18.24%) rocedures were erformed in univentricular hysiology atients. s Descritive statistics were reorted as mean value and. Comarisons between grous were made using either the unaired Student t test or the Mann- Whitney U test where aroriate. Discrete variables were further analyzed by the Yates 2 test. Multivariate stewise logistic regression was used to assess the risk factors for ostoerative comlications and death. al analysis was erformed using a for Windows 8.0 software (StatSoft, Krakow, Poland). A value of less than 0.05 was considered statistically significant. Results Biventricular Physiology Mean, (), SD n 12,136 Univentricular Physiology Mean, (), SD n 2,707 Age 12.1, (11.7 12.2), 7.6 10.6, (10.4 10.9), 6.9 0.001 (days) B.W. 2.9, (2.85 2.88), 0.92 3.11, (3.08 3.13), 0.56 0.001 (kg) ABS 7.08, (7.02 7.13), 2.95 9.8, (9.6 10), 4.8 0.001 ABS Aristotle Basic Score; B.W. body weight; CI confidence interval. Comaring the verified and nonverified sets of data, no difference in hosital mortality (10.5% vs 10.7%, 0.86) and 30-day mortality (8.5% vs 9.2%, 0.630) has been Table 3. Hosital Versus 30-day Mortality 30-day Mortality % Hosital Mortality % All 9.1 10.7 0.001 CPB 13.6 15.9 0.001 non-cpb 5.1 5.9 0.001 non-cpb without PDA 5.2 6.1 0.001 CPB cardioulmonary byass; PDA atent ductus arteriosus.
Ann Thorac Surg KANSY ET AL 2010;89:1255 9 OUTCOMES OF NEONATAL CARDIAC SURGERY 1257 Table 4. Hosital Mortality: Univariate Analysis Alive Mean, (), SD Death Mean, (), SD Age (days) 11.99, (11.9 12.1), 7.5 10.23, (9.9 10.7), 7.3 0.00001 Body weight (kg) 2.9, (2.9 2.93), 0.9 2.8, (2.82 2.89), 0.7 0.0001 Time admission surgery (days) 5.23, (5.0 5.4), 11.6 4.8, (4.5 5.1), 5.8 0.19 ABS 7.3, (7.2 7.4), 3.4 9.57, (9.4 9.7), 3.7 0.001 CPB time (minutes) 143, (140.6 145.4) 94 194, (185.5 202.5), 143 0.001 AoX time (minutes) 75.1, (73.7 78.6), 90.1 78,6, (75.5 81.7), 49,2 0.8 Circulatory arrest time (minutes) 30.2, (29.3 31.1), 21.4 41.2, (39.2 43.2), 24.8 0.0001 ABS Aristotle Basic Score; AoX aortic cross-clam; CI confidence interval; CPB cardioulmonary byass. shown. The number of comlications was significantly higher in the verified set of data (38% vs 28%, 0.001). In univentricular hysiology atients the age was significantly lower, in contrast to body weight, which was higher; also Aristotle Basic Score was higher, as well as the ercentage of CPB rocedures (55.9%) comared with 46% in biventricular hysiology atients ( 0.001) (Table 2). Overall, hosital mortality was 10.7% comared with 9.1% of the 30-day mortality ( 0.001). In all grous hosital mortality was higher than 30-day mortality (Table 3). There was significantly higher hosital mortality in the CPB grou (15.9%) comared with the non-cpb grou (5.9%) ( 0.0001). There was no difference in hosital mortality when comaring the non-cpb grou including atients undergoing atent ductus arteriosus (PDA) closure to the non-cpb grou excluding atients undergoing PDA closure (5.9 % and 6.1%, resectively). Hosital mortality in the PDA closure grou was 5.8%. There was no significant change in hosital mortality related to admission-to-surgery time or aortic cross-clam time. The hosital mortality in atients with univentricular hysiology was 21.6% comared with 12.3% in biventricular hysiology ( 0.001). Body weight below the cutoff value of 2 kg was associated with statistically significant higher mortality ( 0.02) (Table 4). The comlications occurred in 29.2% of all rocedures (41.5% of CPB comared with 17.8% of non-cpb rocedures, 0.0001). No statistically significant difference in the incidence of comlications between the non-cpb grou including atients undergoing PDA closure and the non-cpb grou excluding atients undergoing PDA closure was found (17.8% and 19.9%, resectively). The incidence of comlications after PDA surgical closure was 11.1% (Table 5). Among atients with univentricular hysiology the rate of comlications was 39% and in biventricular hysiology grou 27% ( 0.001). Longer CPB time, aortic crossclam time and circulatory arrest time were found to be redictors of comlications. In the grou in which the circulatory arrest was used, ABS was significantly higher, mean 11.0, (10.9 11.1), 2.8 versus 9.5, (9.48 9.62), 2.3 ( 0.0001). In multivariate stewise logistic regression analysis for all rocedures lower body weight, higher ABS, and univentricular hysiology roved to be statistically significant redictors of hosital mortality (Table 6). In CPB rocedures lower body weight, longer CPB time, longer aortic cross-clam time, longer circulatory arrest time, and univentricular hysiology were found to be statistically significant redictors of hosital mortality (Table 7). Only higher ABS roved to be statistically significant redictors of comlications in multivariate analysis erformed for all rocedures (Table 8). In CPB rocedures, longer CPB time and longer circulatory arrest time were associated with a higher rate of comlications (Table 9). Comment Recent develoments in renatal diagnosis and oerative techniques, as well as imrovements in CPB and intensive care technologies have ositive imact on early outcomes in neonatal congenital heart surgery. Although 30-day mortality continues to decrease, mortality beyond 30 ostoerative days (hosital mortality) remains significant (10.7%) [2]. Although the EACTS Congenital Database is an observational and voluntary registry, enormous effort made during recent years using on-site, back-to-back data verification rotocol, resulted in a Table 5. Incidence of Comlications: Univariate Analysis Alive Mean, (), SD Death Mean, (), SD Age (days) 12.2, (12 12.3), 7.6 10.9, (10.7 11.20), 7.2 0.00001 ABS 6.98, (6.9 7), 3.4 8.98, (8.9 9.1), 3.4 0.001 CPB time (minutes) 139.1, (135.7 142.3), 111.2 167.8, (164.4 171.2), 93.5 0.001 AoX time (minutes) 72.9, (71.7 74.1), 36.4 81.6, (76.8 86.4), 124.3 0.0001 Circulatory arrest time (minutes) 28.6, (27.4 29.8), 22.9 36.5, (35.3 37.6), 21.7 0.00001 ABS Aristotle Basic Score; AoX aortic cross-clam; CI confidence interval; CPB cardioulmonary byass.
1258 KANSY ET AL Ann Thorac Surg OUTCOMES OF NEONATAL CARDIAC SURGERY 2010;89:1255 9 Table 6. Risk Factors for Hosital Death, All Patients: Table 8. Risk Factors for Incidence of Comlications: Age 1.007 0.996 1.018 1.655 0.198 Body weight 1.550 1.428 1.684 108.352 0.0001 ABS 0.841 0.823 0.860 246.813 0.0001 UVH hysiology 1.819 1.554 2.129 55.3 0.0001 ABS Aristotle Basic Score; CI confidence interval; UVH univentricular heart. 12.1% data verification rate, as described earlier. Comaring verified and nonverified data, no statistically significant difference in atient demograhics, hosital mortality, and 30-day mortality was demonstrated. Certain incomlete ostoerative morbidity data identified during the verification rocess resulted in limited values of ostoerative morbidity analysis. In our investigation, univariate analysis erformed for all registered neonates demonstrated that younger age, lower body weight, higher Aristotle Basic Score, and univentricular hysiology are the risk factors for hosital mortality. Body weight below 2.5 kg was also associated with increased mortality in the recent STS Congenital Heart Database study [3]. Having stratified their oulation by Aristotle Basic Comlexity levels 2 through 4, and with risk adjustment for congenital heart surgery-1 levels 2 through 6, investigators found also that lower body weight remained strongly associated with higher mortality. In another metaanalysis of seven series of atients ublished in 2006 [7], authors concluded that lower body weight was associated with higher hosital mortality. In neonates undergoing CPB rocedures, also, circulatory arrest time and longer CPB time were redictors for hosital mortality. This had also been demonstrated earlier [8 10]. In our study ostoerative comlications occurred in 29.2% of atients with higher incidence in neonates with univentricular hysiology. In CPB rocedures, longer CPB and aortic cross-clam times were associated with a higher rate of comlications. Additionally, longer circulatory arrest time was a redictor of increased morbidity. The multivariate analysis confirmed Age 1.005 0.999 1.012 2.778 0.096 Body weight 1.017 0.962 1.075 0.351 0.554 ABS 0.845 0.832 0.858 446.247 0.0001 UVH hysiology 1.078 0.951 1.223 1.371 0.242 ABS Aristotle Basic Score; CI confidence interval; UVH univentricular heart. that lower body weight, longer CPB time, and aortic cross-clam time, as well as longer circulatory arrest and univentricular hysiology, are risk factors for hosital mortality. It has been confirmed that neonates with congenital heart disease have lower birth weight comared with the healthy oulation [9, 11]. It has also been shown that definitive reair in neonates with low body weight can be associated with lower hosital mortality than alliative treatment [9, 12]. There are certain questions that remain unanswered. It has been shown, for examle, that the overall risk of treatment of low body weight neonates is higher. However, there are no data suorting the strategy of ostoning surgery until neonates gain weight. On the contrary, it has been demonstrated that delaying reair has no benefit for the outcomes [13, 14]. To answer this question one should have an access to all atients data; those who underwent surgery and those who have not. In our study, multivariate analysis confirmed that other confounders lay an imortant role for the overall risk of surgical treatment of neonates. In this demanding grou of extremely small babies surgery needs to be not only accurate but also fast, resulting in reduction of cardioulmonary byass exosure and myocardial ischemia. The early surgical outcomes achieved recently in neonates with congenital heart defects are encouraging. The risk stratification tools validated for use with large international multicenter datasets are needed for meaningful analysis of early and late mortality and morbidity rates. In the near future, this analysis should be erformed for the combined STS and EACTS Congenital Database data, which will give us Table 7. Risk Factors for Hosital Death, CPB Grou: Table 9. Risk Factors for Incidence of Comlications, CPB Grou: Age 1.006 0.985 1.027 0.281 0.596 Body weight 1.551 1.256 1.915 16.688 0.0001 ABS 0.969 0.912 1.028 1.088 0.297 CPB time 0.991 0.989 0.993 82.74 0.0001 AoX time 1.008 1.004 1.013 13.179 0.0001 Circulatory arrest time 0.991 0.985 0.996 12.249 0.0001 UVH hysiology 2.05 1.413 0.996 14.33 0.0001 ABS Aristotle Basic Score; AoX aortic cross-clam; CI confidence interval; CPB cardioulmonary byass; UVH univentricular heart. Age 1.003 0.988 1.018 0.164 0.686 Body weight 1.041 0.882 1.229 0.227 0.634 ABS 0.963 0.917 1.011 2.288 0.131 CPB time 0.996 0.994 0.998 12.732 0.0001 AoX time 1.002 0.998 1.005 0.857 0.355 Circulatory arrest time 0.981 0.976 0.986 57.952 0.0001 UVH hysiology 0.855 0.629 1.163 0.991 0.320 ABS Aristotle Basic Score; AoX aortic cross-clam; CI confidence interval; CPB cardioulmonary byass; UVH univentricular heart.
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