Intranasal dexmedetomidine: the ideal drug for sedation in the pediatric echo lab?

BACKGROUND: Intranasal dexmedetomidine is an attractive option for procedural sedation in pediatrics due to ease of administration and its relatively short half-life. This study sought to compare the safety and efficacy of intranasal dexmedetomidine to a historical cohort of pediatric patients sedated using chloral hydrate in a pediatric echo lab. METHODS: Chart review was performed to compare patients sedated between September, 2017 and October, 2019 using chloral hydrate and intranasal dexmedetomidine. Vital signs, time to sedation, duration of sedation, need for second dose of medication, rate of failed sedation, and impact on vital signs were compared between groups. Subgroup analysis was performed for those with complex and cyanotic heart disease. RESULTS: Chloral hydrate was used in 356 patients and intranasal dexmedetomidine in 376. Patient age, complexity of heart disease, and duration of sedation were similar. Rates of failed sedation were very low and similar. Average heart rate and minimum heart rate were lower for those receiving intranasal dexmedetomidine than chloral hydrate. Impact on vital signs was similar for those with complex and cyanotic heart disease. No adverse events occurred in either group. CONCLUSIONS: Sedation with intranasal dexmedetomidine is comparable to chloral hydrate in regards to safety and efficacy for children requiring echocardiography. Consistent with the mechanism of action, patients receiving intranasal dexmedetomidine have a lower heart rate without morbidity.

Prevalence, Risk Factors, and Impact of Obstructive Sleep Apnea in Adults with Congenital Heart Disease.

The objective of our study was to determine the prevalence, risk factors, and the impact of obstructive sleep apnea (OSA) in the adult with congenital heart disease (ACHD). One hundred forty-nine consecutive patients seen in our ACHD program were screened for OSA using the Berlin Questionnaire. Demographic and clinical details on subjects were collected through a chart review. Clinical variables were analyzed to determine risk factors for positive OSA screen, as well as associated outcomes. Seventy-seven (52%) of our cohort were females. The median age of the cohort was 33 years (range = 18-74) and median weight was 79 kg (range = 50-145 kg). Overall, 47 (31%) of our cohort were found to have a positive OSA screen using the Berlin questionnaire. Median age of the patients whom tested positive was 34 years. Compared to patients with a negative screen, patients with a positive OSA screen were more likely to be heavier with a median weight of 99 kg vs 71 kg (p < 0.01) and a larger BMI (31 vs 25 kg/m2, p < 0.01). Overall, 55% of patients whom screened positive were obese (defined as a BMI > 30) compared to 15% in the negative group (p < 0.02). Patients with a positive screen were more likely to have other co-morbidities including diabetes (p < 0.04), hypertension (p < 0.05), depression (p < 0.002), and were more likely to have decreased exercise capacity (p < 0.01) and a defibrillator (p < 0.007). Our data demonstrates that OSA is common in the ACHD patient and is associated with increasing weight and BMI. Patients with a positive screen are at increased risk for multiple co morbidities including diabetes, hypertension, and depression. We believe our data supports the use of screening protocols for OSA in the ACHD population in effort to identify early, treat, and potentially prevent late complications.

Percutaneous melody valve implantation in a native tricuspid valve following failed surgical repair.

Transcatheter valve-in-valve and valve-in-ring implantation has become a common approach to treating patients with failed bioprosthetic tricuspid valves as well as failed surgical repairs of the tricuspid valve where an annuloplasty ring has been utilized. We describe a case where a Melody valve was percutaneously implanted in a native tricuspid valve with severe stenosis following surgical repair without a supporting annuloplasty ring.

Anatomic Repair of Congenitally Corrected Transposition of the Great Arteries: Single-Center Intermediate-Term Experience.

We present our experience for patients who have undergone an anatomic repair (AR) for congenitally corrected transposition of the great arteries (CCTGA) at the Children's Hospital of Wisconsin. A retrospective chart review of patients who underwent AR for CCTGA from 2001 to 2015 was performed. The cohort consisted of 15 patients (74% male). Median age of anatomic repair was 15 months (range 4.5-45.6 months). Four patients had a bidirectional Glenn (BDG) prior to AR. At the time of AR,-9 (60%) underwent Senning/Rastelli procedure, 4 (26.6%) had double switch operation, and 2 (13.3%) underwent only Senning with VSD closure. Median duration of follow-up was 5.5 years (0.05-14 years). Reoperations prior to discharge included BDG, revision of pulmonary venous baffle, closure of residual VSD, and pacemaker placement. Late reoperations included left ventricular outflow tract obstruction repair, conduit replacement, melody valve placement, and pacemaker implantation. At their most recent follow-up, no patient had heart failure symptoms and only 1 had severely diminished function that improved with cardiac resynchronization therapy. Moderate mitral regurgitation was noted in 15% (2/13), and severe in 7% (1/13). Moderate tricuspid regurgitation was noted in 15% (2/13). One patient, 7% (1/13), developed moderate aortic insufficiency. There was a 100% survival at the time of the most recent follow-up. Patients with CCTGA who have undergone AR have excellent functional status and mid-term survival but reinterventions are common. Longer term studies are needed to determine both the extent and spectrum of reinterventions as well as long term survival.

Center Variability in Timing of Stage 2 Palliation and Association with Interstage Mortality: A Report from the National Pediatric Cardiology Quality Improvement Collaborative.

For infants with single-ventricle lesions with aortic arch hypoplasia, the interstage period from discharge following stage 1 palliation (S1P) until stage 2 palliation (S2P) remains high risk. Significant variability among institutions exists around the timing of S2P. We sought to describe institutional variation in timing of S2P, determine the association between timing of S2P and interstage mortality, and determine the impact of earlier S2P on hospital morbidity and mortality. The National Pediatric Cardiology Quality Improvement Collaborative registry was queried. Centers were divided based on median age at S2P into early (n = 15) and late (n = 16) centers using a cutoff of 153 days. Groups were compared using Chi-squared or Wilcoxon rank-sum test. Multivariable logistic regression was used to determine risk factors for interstage mortality. The final cohort included 789 patients from 31 centers. There was intra- and inter-center variability in timing of S2P, with the median age by center ranging from 109 to 214 days. Late centers had a higher mortality (9.9 vs. 5.7 %, p = 0.03) than early centers. However, the event rate (late: 8.2 vs. early: 5.8 deaths per 10,000 interstage days) was not different by group (p = 0.26). Survival to hospital discharge and hospital length of stay following S2P were similar between groups. In conclusion, in a large multi-institution collaborative, the median age at S2P varies among centers. Although optimal timing of S2P remains unclear, centers performing early S2P did not experience worse S2P outcomes and experienced less interstage mortality.

Feeding dysfunction in children with single ventricle following staged palliation.

OBJECTIVE: To determine the prevalence of feeding dysfunction in children with single ventricle defects and identify associated risk factors. STUDY DESIGN: Patients aged 2-6 years with single ventricle physiology presenting for routine cardiology follow-up at the Children's Hospital of Wisconsin were prospectively identified. Parents of the patients completed 2 validated instruments for assessment of feeding dysfunction. Chart review was performed to retrospectively obtain demographic and diagnostic data. RESULTS: Instruments were completed for 56 patients; median age was 39 months. Overall, 28 (50%) patients had some form of feeding dysfunction. Compared with a normal reference population, patients with single ventricle had statistically significant differences in dysfunctional food manipulation (P < .001), mealtime aggression (P = .002), choking/gagging/vomiting (P < .001), resistance to eating (P < .001), and parental aversion to mealtime (P < .001). Weight and height for age z-scores were significantly lower in subjects with feeding dysfunction (-0.84 vs -0.33; P < .05 and -1.46 vs -0.56; P = .001, respectively). Multivariable analysis identified current gastrostomy tube use (P = .02) and a single parent household (P = .01) as risk factors for feeding dysfunction. CONCLUSION: Feeding dysfunction is common in children with single ventricle defects, occurring in 50% of our cohort. Feeding dysfunction is associated with worse growth measures. Current gastrostomy tube use and a single parent household were identified as independent risk factors for feeding dysfunction.

Significant response to oral Etoposide in the treatment of an unresectable cardiac sarcoma.

Primary cardiac sarcomas are rare and carry a poor prognosis. The standard of care is complete resection. Outcomes for patients without complete resection are dismal, and the benefit of adjuvant therapy is uncertain. A 9-year-old girl presented with a large right-sided cardiac mass. After biopsy, the tumor was classified as an undifferentiated sarcoma. Resection was not feasible due to apparent invasion of the right ventricle and atrioventricular groove. Treatment with oral etoposide resulted in a 97% reduction in tumor volume and allowed for complete resection of residual tumor. She is alive with no evidence of disease 25 months from diagnosis.

The spectrum of congenital heart disease and outcomes after surgical repair among children with Turner syndrome: a single-center review.

Turner syndrome (TS), a genetic abnormality affecting 1 in 2,500 people, is commonly associated with congenital heart disease (CHD). However, the surgical outcomes for TS patients have not been well described. This study reviewed the spectrum of CHD in TS at the authors' center. The authors report outcomes after coarctation of the aorta (CoA) repair or staged palliation of hypoplastic left heart syndrome (HLHS) and then compare the surgical outcomes with those of non-TS patients undergoing like repair. This retrospective chart review was conducted at the Children's Hospital of Wisconsin from 1999 to 2011. Of the 173 patients with TS, 77 (44.5 %) were found to have CHD. Left-sided obstructive lesions were the most common. However, the spectrum of CHD was wide and included systemic and pulmonary venous abnormalities as well as abnormalities of the coronary arteries. In the comparative analysis of CoA repair, the TS patients younger than 60 days had longer aortic cross-clamp times (24 vs. 16 min; p = 0.001) and longer hospital stays (12 vs. 6 days; p ≤ 0.0001) than the non-TS patients. At the follow-up assessment after 8.8 ± 9.1 years, 17 % of the TS patients had hypertension, but no patient had required reintervention, and no deaths had occurred. Finally, three of the four TS patients with HLHS died within the first year. The spectrum of CHD within TS is wide and not limited to bicuspid aortic valve or CoA. Additionally, patients with TS undergoing CoA repair may have a more challenging early postoperative course but experience outcomes similar to those of non-TS patients. Finally, patients who have TS combined with HLHS remain a challenging population with generally poor survival.

Inferior sinus venosus defects: anatomic features and echocardiographic correlates.

Inferior sinus venosus defects (SVDs) are rare imperfections located in the inferior portion of the atrial septum, leading to an overriding inferior vena cava (IVC) and an interatrial connection. These defects have increased risk of anomalous pulmonary venous return (PAPVR) and often are confused with secundum atrial septal defects (ASDs) with inferior extension. The authors sought to review their experience with inferior SVDs and to establish at their institution an echocardiographic definition that differentiates inferior SVDs from secundum ASDs with inferior extension. The study identified 161 patients 1.5 to 32 years of age who had undergone repair of a secundum ASD with inferior extension or inferior SVD over the preceding 10 years. All surgical notes, preoperative transthoracic echocardiograms (TTEs), and preoperative transesophageal echocardiograms (TEEs) were reviewed. Based on the surgical notes, 147 patients were classified as having a secundum ASD (147/161, 91 %) and 14 patients (9 %) as having an inferior SVD. The study identified PAPVR in 7 % (1/14) of the patients with inferior SVDs and 3.5 % (5/14) of the patients with secundum ASDs. Surgical diagnosis and preoperative TTE correlated for 143 (89 %) of the 161 patients. Using a strict anatomic and echocardiographic definition with a blinded observer, the majority of the defects (14/18, 78 %) were reclassified correctly after review of their TTE images, and 100 % of the defects were correctly reclassified after TEE image review. Accurate diagnosis of inferior SVDs remains challenging. The data from this study demonstrate that use of a strict anatomic and echocardiographic definition (a defect that originates in the mouth of the IVC and continues into the inferoposterior border of the left atrium, leaving no residual atrial septal tissue at the inferior margin) allows for accurate differentiation between secundum ASDs with inferior extension and inferior SVDs. This differentiation is extremely important in planning for surgical versus device closure of these rare defects.

Aortic aneurysms remain a significant source of morbidity and mortality after use of Dacron(®) patch aortoplasty to repair coarctation of the aorta: results from a single center.

Aortic aneurysm formation after coarctation repair is a serious and life-threatening complication. Repairs using synthetic materials such as Dacron(®) may carry the highest risk of aneurysm formation and rupture. The authors sought to determine the prevalence of aneurysm formation in patients who previously underwent coarctation repair using Dacron(®) patch aortoplasty at their institution. Between 1977 and 1994, 63 patients underwent isolated coarctation repair using Dacron(®) patch aortoplasty. Aneurysms were defined as an aortic dimension 1.5 times that of the aorta at the level of the diaphragm as shown by angiography, computed tomography (CT) scan, or magnetic resonance imaging (MRI). Of 61 early survivors, 29 (47 %) experienced an aneurysm in the area of previous repair. Nine patients (31 %) had spontaneous rupture of the aneurysm, which caused death in seven cases. Elective or emergent aneurysm repair was performed for 20 patients without complication, and 2 patients are being monitored at this writing. The mean interval from patch placement to aneurysm repair was 15 years (range, 4-27 years). Overall freedom from the development of an aortic aneurysm was 97 % at 5 years, 90 % at 10 years, 69 % at 20 years, and 42 % at 25 years. After repair of coarctation using Dacron(®) patch aortoplasty, the risk for aneurysm formation in the area of repair and death from rupture is extremely high. Therefore, in accordance with the 2008 American Heart Association/American College of Cardiology (AHA/ACC) guidelines, all patients with repaired aortic coarctation should undergo either CT or MRI imaging at least every 5 years to assess for aortic aneurysm formation. More frequent imaging should be obtained for patients previously repaired with Dacron(®) patch aortoplasty.

Predicting left ventricular recovery after replacement of a regurgitant aortic valve in pediatric and young adult patients: is it ever too late?

The management of pediatric and adolescent patients with pure aortic valve regurgitation remains challenging and controversial (Christos et al., Eur J Cardiothorac Surg 17:125-133, 2000; Gersony and Sommerville, ACC Curr J Rev 31:97-98, 2000; Hasaniya et al., J Thorac Cardiovasc Surg 127:970-974, 2004; Sabet et al., Mayo Clin 74:14-26, 1999; Tweddell et al., J Thorac Cardiovasc Surg 129:551-558, 2005). We evaluated pediatric and young adult patients who underwent aortic valve replacement (AVR) primarily for aortic regurgitation in an effort to identify preoperative echocardiographic variables that are predictive of left ventricular (LV) recovery following AVR. Twenty-one patients with severe aortic valve regurgitation who underwent AVR were identified. Retrospective chart review for each patient was performed and transthoracic echocardiograms prior to and 6-months after AVR were analyzed. Improvement in LV size based on preoperative LV end-systolic dimension index when compared to 6-months post-AVR was observed in 68% of the patients. Patients with persistent dilation of their left ventricles had a greater preoperative LV end-systolic dimension index (p ≤ 0.05), a greater preoperative LV end-systolic dimension z-score (p ≤ 0.002), and a lower preoperative ejection fraction (EF) (p ≤ 0.001). A similar trend was present between the two cohorts in regards to LV end-diastolic parameters (LV end-diastolic dimension index and z-score), with patients with abnormal LV size at 6-month follow-up having larger preoperative dimensions. Increasing LV systolic dimensions and declining EF appear to be predictors of poor LV recovery following AVR in pediatric and young adult patients. LV end-systolic indices appear to be more predictive than LV end-diastolic indices. AVR should be performed prior to severe LV enlargement defined as an LV end-systolic dimension z-score >4.5.

Renal dysfunction is common among adults after palliation for previous tetralogy of Fallot.

Long-term survival after tetralogy of Fallot (TOF) repair is excellent. However, little is published regarding late noncardiac complications. This study aimed to determine the prevalence and risk factors for renal dysfunction among adults after TOF repair. For this study, 56 adult patients with complete repair of TOF were identified, and their charts were retrospectively reviewed. An estimated glomerular filtration rate (eGFR) for each patient was calculated using the Modification of Diet in Renal Disease formula (MDRD). Using each patient's eGFR, he or she was classified into stages based on the National Kidney Foundation chronic kidney disease (CKD) staging. Clinical parameters were compared among patients with and those without renal dysfunction to identify risk factors for renal impairment. The median estimated eGFR rate for the cohort was 78 ml/min/1.73 m(2). Based on the National Kidney Foundation CKD staging system, 54 % of the patients had at least stage 2 chronic renal disease. The risk factors identified were hypertension (p < 0.01), type 2 diabetes mellitus (p < 0.05), longer follow-up evaluation (p < 0.005), older age at complete repair (p < 0.05), and use of daily diuretics (p < 0.05). After repair of TOF, renal dysfunction is common at late follow-up evaluation. The study findings show the importance of routine assessment of renal function and the need to limit or avoid future episodes of acute kidney injury in this at-risk population.

The Supported vs Unsupported Ross in Pediatric Patients: Neoaortic Root and Ventricular Function.

BACKGROUND: The supported Ross is used to mitigate the neoaortic root dilation that has been described with the unsupported Ross. There is limited literature assessing the efficacy of the supported Ross in young patients. In this study, the fate of the neoaortic root was compared in the supported and unsupported Ross procedure in adolescent patients. METHODS: A retrospective review was performed of patients who underwent the Ross procedure between 1996 and 2019. An analysis was conducted of patients aged 10 to 18 years who underwent the supported and unsupported Ross operation, without a Konno enlargement, to assess for longitudinal echocardiographic changes. Given differences in follow-up time, both regression analysis and Mann-Whitney nonparametric tests were used to correct for time from discharge to most recent follow-up. RESULTS: The median follow-up time for supported and unsupported Ross patients without a Konno enlargement was 2.90 years (0.21-13.03 years) and 12.13 years (2.63-19.47 years), respectively. Unsupported Ross patients experienced a higher rate of change per year in the aortic annulus (P = .003 and P = .014) and aortic sinus (P = .002 and P = .002) diameters, respectively. There was no significant difference in the rate of change of end-diastolic left ventricular internal diameter (P = .703 and P = .92) and aortic insufficiency (P = .687 and P = .215) between the supported and unsupported Ross patients. CONCLUSIONS: Progressive dilation of the neoaortic root in unsupported Ross patients is significantly mitigated with the supported Ross with excellent stability. The supported Ross is safe and effective and may play an increasing role in the management of children with aortic disease.

Timing and technique of pulmonary valve replacement in the patient with tetralogy of Fallot.

Residual right ventricular (RV) outflow tract pathology is universal among patients with repaired tetralogy of Fallot, and pulmonary regurgitation (PR) is also commonly present. Although tolerated in early life, by the second decade of life PR is associated with an increased risk of death because of ventricular arrhythmias. Pulmonary valve replacement (PVR) is a safe procedure that will eliminate PR, but timing and indications are evolving. Patients with arrhythmias or prolonged QRS duration are candidates for PVR. Patients with symptomatic exercise intolerance are likely to have improvement in symptoms and quality of life and should be offered PVR. Cardiac magnetic resonance has become an essential component of the management of the patient with tetralogy of Fallot with PR, and has identified the potential for and limitations of RV remodeling following PVR. Among patients with severe RV enlargement, particularly those with diminished RV or left ventricular function, there is an increased risk of adverse events and even asymptomatic patients with severe PR should be considered for PVR. Valve replacement is accomplished with homografts or heterografts, either stented bioprosthetic valves or valved conduits. In a retrospective analysis of the Children's Hospital of Wisconsin experience with PVR, there was no difference in survival or freedom from reintervention between heterografts and homografts.

Late complications after Takeuchi repair of anomalous left coronary artery from the pulmonary artery: case series and review of literature.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart lesion that if left untreated, results in high mortality. Surgical treatment options include reimplantation of the anomalous coronary ostia, use of extracardiac arterial blood supply, or the Takeuchi procedure. The Takeuchi procedure involves creation of an aortopulmonary window and an intrapulmonary tunnel that baffles the aorta to the ostium of the anomalous left coronary artery. The incidence of late complications following the Takeuchi repair is unknown. The goal of our study was to determine the long-term outcome after palliation of ALCAPA using the Takeuchi Procedure. A total of 9 patients with a history of ALCAPA palliated with the Takeuchi procedure were identified from our surgical database. Chart review was performed. The mean age at time of Takeuchi procedure was 49.6 months (range 5 weeks-14.6 years). There was one late death, of unknown cause. Of the remaining 8 patients, the mean length of follow-up after surgery was 15.9 years (13.5-19.7 years). All 8 survivors had some degree of main pulmonary artery stenosis in the area of the intrapulmonary baffle, with moderate stenosis in 2 and severe stenosis in 1. Three late survivors (38 %) had a baffle leak. Two patients (25 %) had decreased left ventricular systolic function and 3 (38 %) had developed at least moderate mitral valve regurgitation. Three of the 8 late survivors (38 %) required a reoperation for repair of mitral valve regurgitation, baffle leak, and main pulmonary artery (MPA) stenosis. Review of literature demonstrated similar complication rates and need for reoperation following the Takeuchi procedure. Compared with patients after direct reimplantation for ALCAPA at our institution, there was no significant difference in late survival or freedom from reoperation. The Takeuchi procedure is a method to establish a two-coronary repair for ALCAPA. Late complications are common, necessitating lifelong care in a center experienced with caring for adults with congenital heart disease.

The Impact of and Barriers to Cardiac Rehabilitation Following Cardiac Surgery in the Adult With Congenital Heart Disease.

INTRODUCTION: There is a paucity of literature evaluating the impact of and barriers to participation in cardiac rehabilitation (CR) in the adult congenital heart disease population. The aims of this study were to evaluate the impact of CR on physical activity and health-related quality of life, as well as to evaluate the barriers to participation in CR in a post-operative adult congenital heart disease population. METHODS: Patients ≥18 yr of age seen in the Wisconsin Adult Congenital Heart Disease Program and post-open sternotomy surgery from 2010-2015 were eligible for inclusion. Subjects were mailed a novel physical activity survey and the validated EuroQOL-5D 3L health questionnaire. A retrospective medical record review was performed to extract demographic and clinical data. RESULTS: One hundred thirty-five patients underwent open sternotomy surgery from 2010-2015. Of these, 22 were excluded because of intellectual disability, three opted out, and three survey packets were returned to the sender. A total of 54 of the remaining 107 patients returned completed surveys. Of these, 47 (87%) were referred to CR. Thirty-five patients completed the entire CR program (74%). Those who completed CR were more likely to develop a home/independent exercise program (P = .027). Barriers to completing CR included insurance coverage, psychiatric disease, and a perception that CR would not be of benefit. CONCLUSION: Completing CR was associated with developing a home/independent exercise program in post-sternotomy adult patients with congenital heart disease. Barriers to participating in and completing CR in this population could lead to an improved completion rate if modified.

Cardiac Arrest Secondary to Traumatic Aortopulmonary Window During Transcatheter Pulmonary Valve Implantation in Supported Ross.

We present a patient with a supported Ross procedure and severe pulmonary homograft stenosis who developed cardiac arrest while undergoing transcatheter pulmonary valve replacement and was found to have a large iatrogenic aortopulmonary window. Cardiopulmonary resuscitation was initiated followed by covered stent placement, extracorporeal membrane oxygenation support, and ultimately emergent surgery with a good outcome. (Level of Difficulty: Advanced.).

Coronary artery disease screening in adults with congenital heart disease prior to cardiac surgery.

OBJECTIVE: As adults with congenital heart disease (CHD) grow older, preoperative screening for coronary artery disease (CAD) may be indicated prior to CHD surgery. Data regarding the indications for preoperative CAD screening in this population are limited. Current practice is to follow guidelines for patients with valvular heart disease; however, the risk for CAD in certain congenital heart diagnoses may be higher than the general population. This study aimed to assess the results of preoperative CAD screening in patients prior to CHD surgery. DESIGN: Retrospective study. SETTING: Single tertiary center. PATIENTS: Patients ≥35 years that had CHD surgery from 1/1/2007 to 5/1/2017. OUTCOME MEASURES: Data regarding CAD risk factors and preoperative CAD screening results were obtained. Prevalence and risk factors for CAD were analyzed, along with their relationship to perioperative outcomes. RESULTS: A total of 73 patients underwent CAD screening with either cardiac catheterization (56%) or computed tomography angiography (34%) prior to CHD surgery. Overall 16 (22%) patients were found to have CAD. Only two patients had severe coronary stenosis and underwent coronary bypass grafting at time of CHD surgery. Patients with CAD were more likely to be older and have history of hypertension, dyslipidemia, and tobacco smoking. CHD diagnosis was not significantly associated with presence of CAD. CONCLUSION: CAD is common in asymptomatic older patients referred for screening prior to CHD surgery; however, severe CAD requiring concomitant coronary intervention is uncommon. Preoperative CAD screening should be based on age and traditional CAD risk factors, rather than underlying CHD.