Interobserver agreement of the anatomic and physiological classification system for adult congenital heart disease.

The Anatomic and Physiological (AP) classification system proposed in the 2018 American College of Cardiology/American Heart Association adult congenital heart disease (ACHD) guidelines assigns 2 dimensions to each patient: anatomic class (AnatC) and physiological stage (PhyS). This approach has not been tested in practice; we assessed interrater reliability and identified sources of disagreement. METHODS: Consensus definitions for AP categories were developed with input from 4 experts. Research assistants (RAs) assigned AnatC/PhyS for patients in the Boston ACHD Biobank, a prospectively enrolled cohort of ambulatory ACHD patients ≥18 years old seen between 2012 and 2019. Two (of 4) expert reviewers then independently assigned AnatC/PhyS for 41 patients. Interrater reliability was assessed with linearly weighted kappa (κω) for agreement between (1) experts and (2) an RA and an expert. Experts examined disagreements and identified sources of variability and areas requiring clarification. RESULTS: Interexpert agreement for AnatC was excellent, with agreement on 38/41 (92.7%) cases and κω 0.88 [0.75, 1.01]. Agreement for PhyS was less robust, with consensus on 24/41 cases (59.5%), κω 0.57 [0.39, 0.75]. Expert-RA agreement was lower for AnatC (κω 0.77 [0.60, 0.95]), whereas PhyS was similar to interexpert agreement (κω 0.53 [0.34, 0.72]). There was ambiguity in the definitions of (1) arrhythmia status, (2) cyanotic CHD, and (3) valve disease. CONCLUSIONS: Although AnatC can be assessed reliably, that is not true for the PhyS part of the AP classification proposed in the 2018 American College of Cardiology/American Heart Association guidelines. Reliability of PhyS would be strengthened by more precise definitions readily interpretable in clinical practice.

Mobile Cardiac Telemetry Use to Predict Adverse Pregnancy Outcomes in Patients With Congenital Heart Disease.

Background: Patients with congenital heart disease (CHD) have a higher incidence of arrhythmias during pregnancy, yet the utility of mobile cardiac telemetry (MCT) to predict adverse outcomes is unknown. Objectives: The purpose of this study is to determine whether arrhythmias on screening MCT correlate with adverse pregnancy outcomes. Methods: Patients with CHD prospectively enrolled in the Standardized Outcomes in Reproductive Cardiovascular Care initiative underwent 24-hour MCT (within 18 months prior to pregnancy). Positive findings on MCT were defined as episodes of bradyarrhythmia, symptomatic atrioventricular block, ectopic atrial or ventricular activity, and supraventricular or ventricular tachycardia. Clinically significant arrhythmia events (CSAEs) were those requiring medical or device intervention or an emergency room visit. Clinical events during the antepartum, intrapartum, and postpartum periods were compared using Fisher's exact test. Analyses were performed using Stata version 16. Results: In 141 pregnancies in 118 patients with CHD, MCT detected positive findings in 17%. Adverse cardiac outcomes occurred in 11% of pregnancies, of which CSAE occurred in 3.5%. Positive MCT was significantly associated with subsequent CSAE (21% vs 0%, P < 0.001) and cumulative adverse maternal cardiac outcomes (33% vs 7%, P = 0.001) but did not correlate with obstetric (46% vs 41%, P = 0.660) or neonatal outcomes (33% vs 31%, P = 0.810). Of the patients with CSAE, 75% had ≥moderate CHD complexity. Conclusions: Patients with CHD had a high rate of positive MCT findings. This was associated with CSAE and adverse maternal cardiac outcomes. Patients with ≥moderate CHD complexity may benefit from screening MCT to improve preconceptual counseling and planning.

Tuning and external validation of an adult congenital heart disease risk prediction model.

AIMS: Adequate risk prediction can optimize the clinical management in adult congenital heart disease (ACHD). We aimed to update and subsequently validate a previously developed ACHD risk prediction model. METHODS AND RESULTS: A prediction model was developed in a prospective cohort study including 602 moderately or severely complex ACHD patients, enrolled as outpatients at a tertiary centre in the Netherlands (2011-2013). Multivariable Cox regression was used to develop a model for predicting the 1-year risks of death, heart failure (HF), or arrhythmia (primary endpoint). The Boston ACHD Biobank study, a prospectively enrolled cohort (n = 749) of outpatients who visited a referral centre in Boston (2012-2017), was used for external validation. The primary endpoint occurred in 153 (26%) and 191 (28%) patients in the derivation and validation cohorts over median follow-up of 5.6 and 2.3 years, respectively. The final model included 5 out of 14 pre-specified predictors with the following hazard ratios; New York Heart Association class ≥II: 1.92 [95% confidence interval (CI) 1.28-2.90], cardiac medication 2.52 (95% CI 1.72-3.69), ≥1 reintervention after initial repair: 1.56 (95% CI 1.09-2.22), body mass index: 1.04 (95% CI 1.01-1.07), log2 N-terminal pro B-type natriuretic peptide (pmol/L): 1.48 (95% CI 1.32-1.65). At external validation, the model showed good discrimination (C-statistic 0.79, 95% CI 0.74-0.83) and excellent calibration (calibration-in-the-large = -0.002; calibration slope = 0.99). CONCLUSION: These data support the validity and applicability of a parsimonious ACHD risk model based on five readily available clinical variables to accurately predict the 1-year risk of death, HF, or arrhythmia. This risk tool may help guide appropriate care for moderately or severely complex ACHD.

Placental Findings in Pregnancies Complicated by Maternal Cardiovascular Disease.

Background: The incidence of pregnancy in women with cardiovascular disease (CVD) has increased, yet little is known about placental pathology in these women. Objectives: The objectives of this study were to describe placental pathology in pregnancies complicated by maternal CVD and to compare findings among categories of maternal CVD. Methods: A retrospective, single-center study was conducted. Pathology reports for 264 placentas from pregnancies complicated by maternal CVD were reviewed for prespecified pathologic findings which were then compared against maternal characteristics. Results: Placentas were from pregnancies associated with maternal congenital heart disease (n = 171), arrhythmia (n = 43), cardiomyopathy (n = 20), connective tissue disease (n = 20), and valvular heart disease (n = 10). Median maternal age at delivery was 32 years (range: 19-49). Median gestational age at delivery was 39 weeks (range: 25-41). Placental pathology was identified in 75% (199/264) of placentas. Anatomic pathology, primarily small placenta by weight, was present in 45% (119/264) of placentas. Vascular pathology, primarily maternal vascular malperfusion or fetal vascular malperfusion, was seen in 41% (107/264) of placentas. Acute chorioamnionitis and villitis of unknown etiology (VUE) were seen in 23% (61/264) and 11% (28/264) of placentas, respectively. Prevalence of VUE differed across CVD categories (P = 0.008) and was most common in maternal congenital heart disease; there were no differences in anatomic, infectious, and vascular pathologies across CVD categories. Conclusions: Pregnancies among women with CVD commonly demonstrate abnormal placental findings, especially anatomic and vascular pathology. Prevalence of VUE differed across CVD categories. Otherwise, the incidence of specific pathology findings did not differ based on maternal characteristics.

Associations Between Clinical Outcomes and a Recently Proposed Adult Congenital Heart Disease Anatomic and Physiological Classification System.

Background American Heart Association and American College of Cardiology consensus guidelines introduce an adult congenital heart disease anatomic and physiological (AP) classification system. We assessed the association between AP classification and clinical outcomes. Methods and Results Data were collected for 1000 outpatients with ACHD prospectively enrolled between 2012 and 2019. AP classification was assigned based on consensus definitions. Primary outcomes were (1) all-cause mortality and (2) a composite of all-cause mortality or nonelective cardiovascular hospitalization. Cox regression models were developed for AP classification, each component variable, and additional clinical models. Discrimination was assessed using the Harrell C statistic. Over a median follow-up of 2.5 years (1.4-3.9 years), the composite outcome occurred in 185 participants, including 49 deaths. Moderately or severely complex anatomic class (class II/III) and severe physiological stage (stage D) had increased risk of the composite outcome (AP class IID and IIID hazard ratio, 4.46 and 3.73, respectively, versus IIC). AP classification discriminated moderately between patients who did and did not suffer the composite outcome (C statistic, 0.69 [95% CI, 0.67-0.71]), similar to New York Heart Association functional class and NT-proBNP (N-terminal pro-B-type natriuretic peptide); it was more strongly associated with mortality (C statistic, 0.81 [95% CI, 0.78-0.84]), as were NT-proBNP and functional class. A model with AP class and NT-proBNP provided the strongest discrimination for the composite outcome (C statistic, 0.73 [95% CI, 0.71-0.75]) and mortality (C statistic, 0.85 [95% CI, 0.82-0.88]). Conclusions The addition of physiological stage modestly improves the discriminative ability of a purely anatomic classification, but simpler approaches offer equivalent prognostic information. The AP system may be improved by addition of key variables, such as circulating biomarkers, and by avoiding categorization of continuous variables.