A risk adjusted method for comparing adverse outcomes among practitioners in pediatric and congenital cardiac catheterization

Managing confounding and effect modification in pediatric/congenital interventional cardiology research

Measuring the effect of a treatment on outcomes is an important goal for research in pediatric/congenital interventional cardiology. The breadth of anatomic and physiologic variations, patient ages, and genetic syndromes and noncardiac comorbid conditions all represent sources of potential confounding and effect modification that are major obstacles to this goal. If not accounted for, these factors can obscure the "true" treatment effect and lead to spurious conclusions about the relative efficacy and/or safety of therapies. In this review, we discuss the importance of confounding and effect modification in pediatric/congenital interventional cardiology research. We define these terms and discuss strategies (both in study design and data analysis) to mitigate error introduced by confounding and effect modification. The importance of confounding by indication in pediatric/congenital cardiology is discussed along with specific methods to address it.

Cardiopulmonary Resuscitation in the Pediatric Cardiac Catheterization Laboratory: A Report From the American Heart Association's Get With the Guidelines-Resuscitation Registry

OBJECTIVES

Hospitalized children with underlying heart disease are at high risk for cardiac arrest, particularly when they undergo invasive catheterization procedures for diagnostic and therapeutic interventions. Outcomes for children experiencing cardiac arrest in the cardiac catheterization laboratory remain under-reported with few studies reporting survival beyond the catheterization laboratory. We aim to describe survival outcomes after cardiac arrest in the cardiac catheterization laboratory while identifying risk factors associated with hospital mortality after these events.

DESIGN

Retrospective observational study of data from a multicenter cardiac arrest registry from November 2005 to November 2016. Cardiac arrest in the cardiac catheterization laboratory was defined as the need for chest compressions greater than or equal to 1 minute in the cardiac catheterization laboratory. Primary outcome was survival to discharge. Variables analyzed using generalized estimating equations for association with survival included age, illness category (surgical cardiac, medical cardiac), preexisting conditions, pharmacologic interventions, and event duration.

SETTING

American Heart Association's Get With the Guidelines-Resuscitation registry of in-hospital cardiac arrest.

PATIENTS

Consecutive patients less than 18 years old experiencing an index (i.e., first) cardiac arrest event reported to the Get With the Guidelines-Resuscitation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 203 patients met definition of index cardiac arrest in the cardiac catheterization laboratory composed primarily of surgical and medical cardiac patients (54% and 41%, respectively). Children less than 1 year old comprised the majority of patients, 58% (117/203). Overall survival to hospital discharge was 69% (141/203). No differences in survival were observed between surgical and medical cardiac patients (p = 0.15). The majority of deaths (69%, 43/62) occurred in patients less than 1 year old. Bradycardia (with pulse) followed by pulseless electrical activity/asystole were the most common first documented rhythms observed (50% and 27%, respectively). Preexisting metabolic/electrolyte abnormalities (p = 0.02), need for vasoactive infusions (p = 0.03) prior to arrest, and use of calcium products (p = 0.005) were found to be significantly associated with lower rates of survival to discharge on multivariable regression.

CONCLUSIONS

The majority of children experiencing cardiac arrest in the cardiac catheterization laboratory in this large multicenter registry analysis survived to hospital discharge, with no observable difference in outcomes between surgical and medical cardiac patients. Future investigations that focus on stratifying medical complexity in addition to procedural characteristics at the time of catheterization are needed to better identify risks for mortality after cardiac arrest in the cardiac catheterization laboratory.

Failure to Rescue as an Outcome Metric for Pediatric and Congenital Cardiac Catheterization Laboratory Programs: Analysis of Data From the IMPACT Registry

Background

Risk‐adjusted adverse event (AE) rates have been used to measure the quality of pediatric and congenital cardiac catheterization laboratories. In other settings, failure to rescue (FTR) has demonstrated utility as a quality metric.

Methods and Results

A multicenter retrospective cohort study was performed using data from the IMPACT (Improving Adult and Congenital Treatment) Registry between January 2010 and December 2016. A modified FTR metric was developed for pediatric and congenital cardiac catheterization laboratories and then compared with pooled AEs. The associations between patient‐ and hospital‐level factors and outcomes were evaluated using hierarchical logistic regression models. Hospital risk standardized ratios were then calculated. Rankings of risk standardized ratios for each outcome were compared to determine whether AEs and FTR identified the same high‐ and low‐performing centers. During the study period, 77 580 catheterizations were performed at 91 hospitals. Higher annual hospital catheterization volume was associated with lower odds of FTR (odds ratio: 0.68 per 300 cases; P=0.0003). No association was seen between catheterization volume and odds of AEs. Odds of AEs were instead associated with patient‐ and procedure‐level factors. There was no correlation between risk standardized ratio ranks for FTR and pooled AEs (P=0.46). Hospital ranks by catheterization volume and FTR were associated (r=−0.28, P=0.01) with the largest volume hospitals having the lowest risk of FTR.

Conclusions

In contrast to AEs, FTR was not strongly associated with patient‐ and procedure‐level factors and was significantly associated with pediatric and congenital cardiac catheterization laboratory volume. Hospital rankings based on FTR and AEs were not significantly correlated. We conclude that FTR is a complementary measure of catheterization laboratory quality and should be included in future research and quality‐improvement projects.

Anesthesia for high-risk procedures in the catheterization laboratory

Recent advances in catheterization and imaging technology allow for more complex procedures to be performed in the catheterization laboratory. A number of lesions are now amenable to a percutaneous procedure, eliminating or at least postponing the need for a surgical intervention. Due to the increase in the complexity of the procedures performed, the involvement of anesthesiologists and their close collaboration with the interventional cardiologists have increased. It is important to understand the physiology and pathophysiology of the patients and to anticipate the plans and the potential complications in order to manage them. We are witnessing a rise in the number of complex interventions in newborns and infants, such as balloon valvotomy (critical aortic stenosis, pulmonary stenosis), radio frequency perforation (of pulmonary atresia and intact ventricular septum), right ventricular outflow tract stenting (in Tetralogy of Fallot), ductal stenting (in some ductus-dependent pulmonary circulation), and combined with a surgical procedure (hybrid procedure for hypoplastic left heart syndrome). Multiple registries have been created in order to understand and improve outcomes of patients with congenital heart disease undergoing catheterization procedures and to develop performance and quality metrics, from which data regarding anesthetic-related risks can be extrapolated. Experienced personnel and a multidisciplinary team approach with direct communication among the team members is a must to ensure anticipation and management of critical events when they occur.

A Model for Assessment of Catheterization Risk in Adults With Congenital Heart Disease

The purpose of this study was to define the risk for adults with congenital heart disease who underwent cardiac catheterization and to propose a precatheterization risk scoring system. Data were prospectively collected using a multicenter registry of the Congenital Cardiovascular Interventional Study Consortium. The occurrence of serious adverse events (SAE) was correlated with 12 predefined variables. Catheterization RISk in Adult patients (CRISA) score was derived using multivariate logistic regression with backward elimination model selection method. The CRISA score was compared with the American Society of Anesthesiology score and a consensus-derived, 20-point risk score based on their ability to predict SAE. From June 2008 to September 2017, 300 adjudicated SAE's occurred in 7317 catheterization procedures (overall SAE rate 4.1%) performed in adults over 18 years of age at 27 contributing centers. Nine of the 12 tested variables were ultimately included in the CRISA score. CRISA score positively correlated with risk of SAE, and was superior to American Society of Anesthesiology and the 20-point risk score in predicting SAE. Minimal (CRISA score 0 to 2), low (3 to 7), moderate (8 to 10) and high (≥11) risk categories were identified, corresponding to 0.5%, 3.2%, 7.9%, and 16.7% risk of SAE, respectfully. In conclusion, the CRISA score reliably predicts risk of SAE in adults with congenital heart disease who underwent cardiac catheterization and may be useful for preprocedural risk assessment.

Modeling Major Adverse Outcomes of Pediatric and Adult Patients With Congenital Heart Disease Undergoing Cardiac Catheterization: Observations From the NCDR IMPACT Registry (National Cardiovascular Data Registry Improving Pediatric and Adult Congenital Treatment)

BACKGROUND

Risk standardization for adverse events after congenital cardiac catheterization is needed to equitably compare patient outcomes among different hospitals as a foundation for quality improvement. The goal of this project was to develop a risk-standardization methodology to adjust for patient characteristics when comparing major adverse outcomes in the NCDR's (National Cardiovascular Data Registry) IMPACT Registry (Improving Pediatric and Adult Congenital Treatment).

METHODS

Between January 2011 and March 2014, 39 725 consecutive patients within IMPACT undergoing cardiac catheterization were identified. Given the heterogeneity of interventional procedures for congenital heart disease, new procedure-type risk categories were derived with empirical data and expert opinion, as were markers of hemodynamic vulnerability. A multivariable hierarchical logistic regression model to identify patient and procedural characteristics predictive of a major adverse event or death after cardiac catheterization was derived in 70% of the cohort and validated in the remaining 30%.

RESULTS

The rate of major adverse event or death was 7.1% and 7.2% in the derivation and validation cohorts, respectively. Six procedure-type risk categories and 6 independent indicators of hemodynamic vulnerability were identified. The final risk adjustment model included procedure-type risk category, number of hemodynamic vulnerability indicators, renal insufficiency, single-ventricle physiology, and coagulation disorder. The model had good discrimination, with a C-statistic of 0.76 and 0.75 in the derivation and validation cohorts, respectively. Model calibration in the validation cohort was excellent, with a slope of 0.97 (standard error, 0.04; P value [for difference from 1] =0.53) and an intercept of 0.007 (standard error, 0.12; P value [for difference from 0] =0.95).

CONCLUSIONS

The creation of a validated risk-standardization model for adverse outcomes after congenital cardiac catheterization can support reporting of risk-adjusted outcomes in the IMPACT Registry as a foundation for quality improvement.

Paediatric cardiac catheterisation in Norway: rates and types of complications in new terms

We determined the incidence, type, and severity of complications after cardiac catheterisation in children with heart disease in Norway, and we present the results in terms of the International Paediatric and Congenital Cardiac Code (IPCCC) nomenclature for complications. All paediatric cardiac catheterisations in Norway are performed in one clinical centre. All procedures performed during a 5-year period beginning in 2010 were prospectively registered, and medical records for cases with complications were reviewed to confirm the event and to re-classify the type, severity, and attributability of the complication according to the IPCCC nomenclature. Univariate and multivariate analyses were performed to identify possible risk predictors. A total of 1318 catheterisations performed on 941 patients were included in the present study, of which 68% were interventional. The complication and major complication rates were 5.5 and 1.4%, respectively. Trauma to the vessels or the myocardium, haemodynamic adverse events, and arrhythmias were the most common types of complications. In the multivariate model, weight <4 kg (odds ratios, 3.0; 95% confidence intervals: 1.6-5.8) and risk category 5 (odds ratios, 5.1; 95% confidence intervals: 2.1-12.3) were significant risk predictors for any complication. In spite of a high rate of interventions, the complication rates in this study were similar to older studies, but diverging methods and terminology limit the comparability. We strongly suggest general use of the proposed IPCCC classification system for registration and reports of complications for paediatric cardiac catheterisations.

Transcatheter Occlusion of the Patent Ductus Arteriosus in 747 Infants <6 kg: Insights From the NCDR IMPACT Registry

OBJECTIVES

The authors sought to identify risk factors associated with major adverse events (MAEs) in infants <6 kg undergoing transcatheter patent ductus arteriosus (PDA) occlusion.

BACKGROUND

Transcatheter PDA occlusion is among the safest of interventional cardiac procedures in adults and older children, but use among infants <6 kg has not been characterized adequately.

METHODS

Using the IMPACT (IMproving Pediatric and Adult Congenital Treatments) registry, we identified infants <6 kg undergoing transcatheter PDA occlusion (January 1, 2011, to March 1, 2015). Using mixed-effects multivariate regression, the authors assessed characteristics predictive of MAE or composite failure (procedural failure or MAE). Individual safety metrics (e.g., embolization, malposition) were also examined for differences across weight thresholds: extremely low weight (LW) (<2 kg), very LW (2 to <4 kg), and LW (4 to <6 kg).

RESULTS

Transcatheter PDA occlusion was attempted in 747 infants <6 kg at 73 hospitals. Rate of procedural success was 94.3%. MAEs were observed in 12.6% of cases; the most common events were acute arterial injury and device embolization in 3.5% and 2.4% of cases, respectively. Younger age (<30 days) was associated with greater risk of a MAE (risk ratio: 3.3; 95% confidence interval: 1.5 to 7.6) and composite failure (risk ratio: 3.0; 95% confidence interval: 1.4 to 6.7). Risk of embolization was higher among extremely LW (10.5%) than very LW or LW infants (1.6% and 2.5%, respectively; p = 0.050).

CONCLUSIONS

Among infants <6 kg, transcatheter PDA occlusion is technically feasible, but risks of MAE are noteworthy. These findings may help inform patient selection and procedural approach for transcatheter PDA occlusion and direct targeted research efforts to support the practice of evidence-based medicine.

Predictors of Catastrophic Adverse Outcomes in Children With Pulmonary Hypertension Undergoing Cardiac Catheterization: A Multi-Institutional Analysis From the Pediatric Health Information Systems Database

BACKGROUND

Cardiac catheterization is the standard of care procedure for diagnosis, choice of therapy, and longitudinal follow-up of children and adults with pulmonary hypertension (PH). However, the procedure is invasive and has risks associated with both the procedure and recovery period.

OBJECTIVES

The purpose of this study was to identify risk factors for catastrophic adverse outcomes in children with PH undergoing cardiac catheterization.

METHODS

We studied children and young adults up to 21 years of age with PH undergoing 1 or more cardiac catheterization at centers participating in the Pediatric Health Information Systems database between 2007 and 2012. Using mixed-effects multivariable regression, we assessed the association between pre-specified subject- and procedure-level covariates and the risk of the composite outcome of death or initiation of mechanical circulatory support within 1 day of cardiac catheterization after adjustment for patient- and procedure-level factors.

RESULTS

A total of 6,339 procedures performed on 4,401 patients with a diagnosis of PH from 38 of 43 centers contributing data to the Pediatric Health Information Systems database were included. The observed risk of composite outcome was 3.5%. In multivariate modeling, the adjusted risk of the composite outcome was 3.3%. Younger age at catheterization, cardiac operation in the same admission as the catheterization, pre-procedural systemic vasodilator infusion, and hemodialysis were independently associated with an increased risk of adverse outcomes. Pre-procedural use of pulmonary vasodilators was associated with reduced risk of composite outcome.

CONCLUSIONS

The risk of cardiac catheterization in children and young adults with PH is high relative to previously reported risk in other pediatric populations. The risk is influenced by patient-level factors. Further research is necessary to determine whether knowledge of these factors can be translated into practices that improve outcomes for children with PH.

CRISP: Catheterization RISk score for Pediatrics: A Report from the Congenital Cardiac Interventional Study Consortium (CCISC)

OBJECTIVES

We sought to develop a scoring system that predicts the risk of serious adverse events (SAE's) for individual pediatric patients undergoing cardiac catheterization procedures.

BACKGROUND

Systematic assessment of risk of SAE in pediatric catheterization can be challenging in view of a wide variation in procedure and patient complexity as well as rapidly evolving technology.

METHODS

A 10 component scoring system was originally developed based on expert consensus and review of the existing literature. Data from an international multi-institutional catheterization registry (CCISC) between 2008 and 2013 were used to validate this scoring system. In addition we used multivariate methods to further refine the original risk score to improve its predictive power of SAE's.

RESULTS

Univariate analysis confirmed the strong correlation of each of the 10 components of the original risk score with SAE attributed to a pediatric cardiac catheterization (P < 0.001 for all variables). Multivariate analysis resulted in a modified risk score (CRISP) that corresponds to an increase in value of area under a receiver operating characteristic curve (AUC) from 0.715 to 0.741.

CONCLUSION

The CRISP score predicts risk of occurrence of an SAE for individual patients undergoing pediatric cardiac catheterization procedures.

Developing tools to measure quality in congenital catheterization and interventions: the congenital cardiac catheterization project on outcomes (C3PO)

The broad range of relatively rare procedures performed in pediatric cardiac catheterization laboratories has made the standardization of care and risk assessment in the field statistically quite problematic. However, with the growing number of patients who undergo cardiac catheterization, it has become imperative that the cardiology community overcomes these challenges to study patient outcomes. The Congenital Cardiac Catheterization Project on Outcomes was able to develop benchmarks, tools for measurement, and risk adjustment methods while exploring procedural efficacy. Based on the success of these efforts, the collaborative is pursuing a follow-up project, the Congenital Cardiac Catheterization Project on Outcomes-Quality Improvement, aimed at improving the outcomes for all patients undergoing catheterization for congenital heart disease by reducing radiation exposure.

Adjusting for Risk Associated With Pediatric and Congenital Cardiac Catheterization: A Report From the NCDR IMPACT Registry

BACKGROUND

As US health care increasingly focuses on outcomes as a means for quantifying quality, there is a growing demand for risk models that can account for the variability of patients treated at different hospitals so that equitable comparisons between institutions can be made. We sought to apply aspects of prior risk-standardization methodology to begin development of a risk-standardization tool for the National Cardiovascular Data Registry (NCDR) IMPACT (Improving Pediatric and Adult Congenital Treatment) Registry.

METHODS AND RESULTS

Using IMPACT, we identified all patients undergoing diagnostic or interventional cardiac catheterization between January 2011 and March 2013. Multivariable hierarchical logistic regression was used to identify patient and procedural characteristics predictive of experiencing a major adverse event after cardiac catheterization. A total of 19,608 cardiac catheterizations were performed between January 2011 and March 2013. Among all cases, a major adverse event occurred in 378 of all cases (1.9%). After multivariable adjustment, 8 variables were identified as critical for risk standardization: patient age, renal insufficiency, single-ventricle physiology, procedure-type risk group, low systemic saturation, low mixed venous saturation, elevated systemic ventricular end-diastolic pressure, and elevated main pulmonary artery pressures. The model had good discrimination (C statistic, 0.70), confirmed by bootstrap validation (validation C statistic, 0.69).

CONCLUSIONS

Using prior risk-standardization efforts as a foundation, we developed and internally validated a model to predict the occurrence of a major adverse event after cardiac catheterization for congenital heart disease. Future efforts should be directed toward further refinement of the model variables within this large, multicenter data set.

Effect of center catheterization volume on risk of catastrophic adverse event after cardiac catheterization in children

BACKGROUND

Procedural volume has been shown to be associated with outcome in cardiac catheterization and intervention in adults. The impact of center-level factors (such as volume) and their interaction with subject- and procedure-level factors on outcome after cardiac catheterization in children is not well described. We hypothesized that higher center catheterization volume would be associated with lower risk of catastrophic adverse events.

METHODS

We studied children and young adults 0 to 21 years of age undergoing one or more cardiac catheterizations at centers participating in the Pediatric Health Information Systems database between 2007 and 2012. Using mixed-effects multivariable regression, we assessed the association between center catheterization volumes and the risk of a composite outcome of death and/or initiation of mechanical circulatory support within 1 day of cardiac catheterization adjusting for patient- and procedure-level factors.

RESULTS

A total of 63,994 procedures performed on 40,612 individuals from 38 of 43 centers contributing data to the Pediatric Health Information Systems database were included. The adjusted risk of the composite outcome was 0.1%. Increasing annual catheterization laboratory volume was independently associated with reduced risk of the composite outcome (odds ratio per a 100-procedure/y increment 0.78 [95% CI 0.65-0.93], P < .006). Younger age at catheterization, previous cardiac operation in the same admission as the catheterization, preprocedural vasoactive medications, and hemodialysis were also independently associated with an increased risk of adverse outcomes.

CONCLUSIONS

Higher cardiac catheterization laboratory volume was associated with reduced risk of catastrophic adverse outcome in the immediate postcatheterization period in children. The observed benefit of catheterization at a larger volume center may be attributable to transmissible best practices or inextricable benefits of larger systems.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

Indications for cardiovascular magnetic resonance in children with congenital and acquired heart disease: an expert consensus paper of the Imaging Working Group of the AEPC and the Cardiovascular Magnetic Resonance Section of the EACVI

This article provides expert opinion on the use of cardiovascular magnetic resonance (CMR) in young patients with congenital heart disease (CHD) and in specific clinical situations. As peculiar challenges apply to imaging children, paediatric aspects are repeatedly discussed. The first section of the paper addresses settings and techniques, including the basic sequences used in paediatric CMR, safety, and sedation. In the second section, the indication, application, and clinical relevance of CMR in the most frequent CHD are discussed in detail. In the current era of multimodality imaging, the strengths of CMR are compared with other imaging modalities. At the end of each chapter, a brief summary with expert consensus key points is provided. The recommendations provided are strongly clinically oriented. The paper addresses not only imagers performing CMR, but also clinical cardiologists who want to know which information can be obtained by CMR and how to integrate it in clinical decision-making.

Incidence and management of life-threatening adverse events during cardiac catheterization for congenital heart disease

Continued advancements in congenital cardiac catheterization and interventions have resulted in increased patient and procedural complexity. Anticipation of life-threatening events and required rescue measures is a critical component to preprocedural preparation. We sought to determine the incidence and nature of life-threatening adverse events in congenital and pediatric cardiac catheterization, risk factors, and resources necessary to anticipate and manage events. Data from 8905 cases performed at the 8 participating institutions of the Congenital Cardiac Catheterization Project on Outcomes were captured between 2007 and 2010 [median 1,095/site (range 133-3,802)]. The incidence of all life-threatening events was 2.1 % [95 % confidence interval (CI) 1.8-2.4 %], whereas mortality was 0.28 % (95 % CI 0.18-0.41 %). Fifty-seven life-threatening events required cardiopulmonary resuscitation, whereas 9 % required extracorporeal membrane oxygenation. Use of a risk adjustment model showed that age <1 year [odd ratio (OR) 1.9, 95 % CI 1.4-2.7, p < 0.001], hemodynamic vulnerability (OR 1.6, 95 % CI 1.1-2.3, p < 0.01), and procedure risk (category 3: OR 2.3, 95 % CI 1.3-4.1; category 4: OR 4.2, 95 % CI 2.4-7.4) were predictors of life-threatening events. Using this model, standardized life-threatening event ratios were calculated, thus showing that one institution had a life-threatening event rate greater than expected. Congenital cardiac catheterization and intervention can be performed safely with a low rate of life-threatening events and mortality; preprocedural evaluation of risk may optimize preparation of emergency rescue and bailout procedures. Risk predictors (age < 1, hemodynamic vulnerability, and procedure risk category) can enhance preprocedural patient risk stratification and planning.

Catheterization for Congenital Heart Disease Adjustment for Risk Method (CHARM)

OBJECTIVES

This study sought to develop a method to adjust for case mix complexity in catheterization for congenital heart disease to allow equitable comparisons of adverse event (AE) rates.

BACKGROUND

The C3PO (Congenital Cardiac Catheterization Project on Outcomes) has been prospectively collecting data using a Web-based data entry tool on all catheterization cases at 8 pediatric institutions since 2007.

METHODS

A multivariable logistic regression model with high-severity AE outcome was built using a random sample of 75% of cases in the multicenter cohort; the models were assessed in the remaining 25%. Model discrimination was assessed by the C-statistic and calibration with Hosmer-Lemeshow test. The final models were used to calculate standardized AE ratios.

RESULTS

Between August 2007 and December 2009, 9,362 cases were recorded at 8 pediatric institutions of which high-severity events occurred in 454 cases (5%). Assessment of empirical data yielded 4 independent indicators of hemodynamic vulnerability. Final multivariable models included procedure type risk category (odds ratios [OR] for category: 2 = 2.4, 3 = 4.9, 4 = 7.6, all p < 0.001), number of hemodynamic indicators (OR for 1 indicator = 1.5, ≥2 = 1.8, p = 0.005 and p < 0.001), and age <1 year (OR: 1.3, p = 0.04), C-statistic 0.737, and Hosmer-Lemeshow test p = 0.74. Models performed well in the validation dataset, C-statistic 0.734. Institutional event rates ranged from 1.91% to 7.37% and standardized AE ratios ranged from 0.61 to 1.41.

CONCLUSIONS

Using CHARM (Catheterization for Congenital Heart Disease Adjustment for Risk Method) to adjust for case mix complexity should allow comparisons of AE among institutions performing catheterization for congenital heart disease.

Report from The International Society for Nomenclature of Paediatric and Congenital Heart Disease: cardiovascular catheterisation for congenital and paediatric cardiac disease (Part 2 - Nomenclature of complications associated with interventional cardiology)

Interventional cardiology for paediatric and congenital cardiac disease is a relatively young and rapidly evolving field. As the profession begins to establish multi-institutional databases, a universal system of nomenclature is necessary for the field of interventional cardiology for paediatric and congenital cardiac disease. The purpose of this paper is to present the results of the efforts of The International Society for Nomenclature of Paediatric and Congenital Heart Disease to establish a system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease, focusing both on procedural nomenclature and the nomenclature of complications associated with interventional cardiology. This system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease is a component of The International Paediatric and Congenital Cardiac Code. This manuscript is the second part of the two-part series. Part 1 covered the procedural nomenclature associated with interventional cardiology as treatment for paediatric and congenital cardiac disease. Part 2 will cover the nomenclature of complications associated with interventional cardiology as treatment for paediatric and congenital cardiac disease.

Congenital heart disease: cardiovascular MR imaging by using an intravascular blood pool contrast agent

PURPOSE

To compare the image quality and diagnostic performance of a contrast agent-specific inversion-recovery (IR) steady-state free precession (SSFP) magnetic resonance (MR) imaging sequence performed by using an intravascular contrast agent (gadofosveset trisodium) with those of a commonly used T2-prepared SSFP sequence performed by using an extravascular (gadopentetate dimeglumine) and an intravascular (gadofosveset trisodium) contrast agent in patients with congenital heart disease (CHD).

MATERIALS AND METHODS

The local ethics committee and the United Kingdom Medicines and Healthcare products Regulatory Agency approved this study. Patient informed consent was obtained. Twenty-three patients with CHD were examined by using a 1.5-T MR imaging unit and a 32-channel coil. Gadopentetate dimeglumine and gadofosveset trisodium were used in the same patient on consecutive days. Vessel wall sharpness, contrast-to-noise ratios (CNRs), image quality, and diagnostic performance achieved by using the IR SSFP sequence with gadofosveset trisodium were compared with those achieved by using the T2-prepared SSFP sequence with gadopentetate dimeglumine and gadofosveset trisodium and with those achieved at respective contrast material-enhanced MR angiographic examinations. The Wilcoxon rank sum test was used to compare categoric variables; t tests were used to compare continuous variables.

RESULTS

Use of the IR SSFP sequence with gadofosveset trisodium significantly improved vessel wall sharpness, CNRs, and image quality (P < .05 for all) for all investigated intra- and extracardiac structures compared with the T2-prepared SSFP sequence with gadopentetate dimeglumine and gadofosveset trisodium and the respective contrast-enhanced MR angiographic examinations. With use of the IR SSFP sequence with gadofosveset trisodium, new, unsuspected diseases (five [22%] of 23) were diagnosed, while other diseases could be excluded (15 [65%] of 23). Information available from echocardiography (n = 23), conventional angiography (n = 4), and/or surgery (n = 1) confirmed all diagnoses.

CONCLUSION

IR SSFP with gadofosveset trisodium improved image quality and diagnostic performance, allowing a more accurate and complete assessment of cardiovascular anatomy in patients with CHD compared with T2-prepared SSFP with gadopentetate dimeglumine and gadofosveset trisodium and respective contrast-enhanced MR angiographic examinations.

Procedure-type risk categories for pediatric and congenital cardiac catheterization

BACKGROUND

The Congenital Cardiac Catheterization Project on Outcomes (C3PO) was established to develop outcome assessment methods for pediatric catheterization.

METHODS AND RESULTS

Six sites have been recording demographic, procedural and immediate outcome data on all cases, using a web-based system since February 2007. A sample of data was independently audited for validity and data completeness. In 2006, participants categorized 84 procedure types into 6 categories by anticipated risk of an adverse event (AE). Consensus and empirical methods were used to determine final procedure risk categories, based on the outcomes: any AE (level 1 to 5); AE level 3, 4, or 5; and death or life-threatening event (level 4 or 5). The final models were then evaluated for validity in a prospectively collected data set between May 2008 and December 31, 2009. Between February 2007 and April 2008, 3756 cases were recorded, 558 (14.9%) with any AE; 226 (6.0%) level 3, 4, or 5; and 73 (1.9%) level 4 or 5. General estimating equations models using 6 consensus-based risk categories were moderately predictive of AE occurrence (c-statistics: 0.644, 0.664, and 0.707). The participant panel made adjustments based on the collected empirical data supported by clinical judgment. These decisions yielded 4 procedure risk categories; the final models had improved discrimination, with c-statistics of 0.699, 0.725, and 0.765. Similar discrimination was observed in the performance data set (n=7043), with c-statistics of 0.672, 0.708, and 0.721.

CONCLUSIONS

Procedure-type risk categories are associated with different complication rates in our data set and could be an important variable in risk adjustment models for pediatric catheterization.

Detection of coronary artery anomalies in infants and young children with congenital heart disease by using MR imaging

PURPOSE

To evaluate the feasibility and accuracy of magnetic resonance (MR) coronary angiography for the detection of coronary artery anomalies in infants and children by using surgical findings as a reference.

MATERIALS AND METHODS

The data analysis was approved by the institutional review board. One hundred children with congenital heart disease underwent MR coronary angiography while under general anesthesia (mean age ± standard deviation, 3.9 years ± 3; age range, 0.2-11 years). A navigator-gated, T2-prepared, three-dimensional steady-state free precession whole-heart protocol (isotropic voxel size, 1.0-1.3 mm(3); mean imaging time, 4.6 minutes ± 1.2; mean navigator efficiency, 70%; 3-mm gating window) was used after injection of gadopentetate dimeglumine. The cardiac rest period (end systole or middiastole) and acquisition window were prospectively assessed for each patient. Coronary artery image quality (score of 0 [nondiagnostic] to 4 [excellent]), vessel sharpness, and coronary artery anomalies were assessed by two observers. Surgery was performed in 58 patients, and those findings were used to define accuracy. Variables were assessed between age groups by using either analysis of variance or Kruskal-Wallis tests.

RESULTS

Diagnostic image quality (score, ≥1 for all coronary artery segments) was obtained in 46 of the 58 patients (79%) who underwent surgery. The origin and course of the coronary artery anatomy depicted with MR imaging was confirmed at surgery in all 46 patients-including the four (9%) with substantial coronary artery anomalies. Diagnostic-quality images were obtained in 84 of the 100 patients. The rate of success improved significantly when patients were older than 4 months (88% for patients >4 months vs 17% for patients ≤4 months, P < .001).

CONCLUSION

Improved whole-heart MR coronary angiography enables accurate detection of abnormal origin and course of the coronary artery system even in very young patients with congenital heart disease.