Adherence to clinical practice guidelines for pulmonary valve intervention after tetralogy of Fallot repair: A nationwide cohort study

Abstract

Objectives: To determine guideline adherence pertaining to pulmonary valve replacement (PVR) referral after tetralogy of Fallot (TOF) repair.

Methods: Children and adults with cardiovascular magnetic resonance imaging scans and at least moderate pulmonary regurgitation were prospectively enrolled in the Comprehensive Outcomes Registry Late After TOF Repair (CORRELATE). Individuals with previous PVR were excluded. Patients were classified according to presence (+) versus absence (-) of PVR and presence (+) versus absence (-) of contemporaneous guideline satisfaction. A validated score (specific activity scale [SAS]) classified adult symptom status.

Results: In total, 498 participants (57% male, mean age 32 ± 14 years) were enrolled from 14 Canadian centers (2013-2020). Mean follow-up was 3.8 ± 1.8 years. Guideline criteria for PVR were satisfied for the majority (n = 422/498, 85%), although referral for PVR occurred only in a minority (n = 167/498, 34%). At PVR referral, most were asymptomatic (75% in SAS class 1). One participant (0.6%) received PVR without meeting criteria (PVR+/indication-). The remainder (n = 75/498, 15%) did not meet criteria for and did not receive PVR (PVR-/indication-). Abnormal cardiovascular imaging was the most commonly cited indication for PVR (n = 61/123, 50%). The SAS class and ratio of right to left end-diastolic volumes were independent predictors of PVR in a multivariable analysis (hazard ratio, 3.33; 95% confidence interval, 1.92-5.8, P < .0001; hazard ratio, 2.78; 95% confidence interval, 2.18-3.55, P < .0001).

Conclusions: Although a majority of patients met guideline criteria for PVR, only a minority were referred for intervention. Abnormal cardiovascular imaging was the most common indication for referral. Further research will be necessary to establish the longer-term clinical impact of varying PVR referral strategies.

Keywords: cardiac MRI; guidelines; pulmonary valve replacement; tetralogy of Fallot.

Graphical abstract

Study flow and comparison of indications for PVR versus receipt of PVR by enrollment era. CMR, Cardiovascular magnetic resonance imaging; PR, pulmonary regurgitation; PVR, pulmonary valve replacement; rTOF, repaired tetralogy of Fallot. Portions of this figure created with BioRender.com.

Figure 1

Time-to-event analysis demonstrating indications for and receipt of pulmonary valve replacement (PVR) stratified by year of enrollment. Shown are the proportion of subjects who met guideline criteria for PVR over the entire follow-up period (A), within the first year after enrollment (B), and the proportion of patients who received PVR (C) with 95% confidence intervals (shaded regions).

Figure 2

A, Classification of right ventricular end-diastolic volume indexed (RVEDVi) stratified according to indication for versus receipt of pulmonary valve replacement (PVR). Scatter and box plots to depict right ventricular end-diastolic volume indexed (RVEDVi) stratified by indication for PVR and referral for intervention. The cohort of 498 patients was classified as follows: PVR+/indication+ (n = 166), PVR–/indication+ (n = 256), and PVR–/indication– (n = 75). Box borders represent the 25th percentile and 75th percentile respectively. The horizontal line represents the median. B, Trends in right ventricular end-diastolic volumes closest to the time of PVR according to year of referral. Trends in RVEDVi at the time of PVR according to year of intervention. Comparison is made between volumes at the beginning and end of the study period (2013-2014 vs 2019-2020). Of note, publication of the American Heart Association/American College of Cardiology Guidelines occurred in 2018, as detailed in the text. ∗P value comparing RVEDVi 2013-2014 versus 2019-2020; shown are 25%ile and 75%ile at borders with median (central bar).

Figure 3

Indications for pulmonary valve replacement referral among patients who underwent intervention, as reported by referring physician. Bars shown in blue represent actual indications. Bars shown in orange represent predicted indications based on guidelines. Portions of this figure created with BioRender.com.

Figure 4

Graphical abstract. What is clinician adherence to guidelines for pulmonary valve replacement (PVR) after tetralogy of Fallot repair? In this study of 498 individual enrolled across 14 Canadian centers, guideline indications for PVR were met in the majority of patients, but only a minority were referred for PVR. Independent predictors of receipt of PVR were symptoms and right ventricular size. ECG, Electrocardiogram; EDV, end-diastolic volume; EF, ejection fraction, ESV, end-systolic volume; LV, left ventricle; RV, right ventricle; RVp, right ventricular pressure; VO₂, aerobic capacity. Portions of this figure created with BioRender.com.

Figure E1

Guideline indications defined in alignment with contemporaneous guidelines which varied according to year of patient enrollment and timing of cardiovascular investigations. RVEDVi, Right ventricular end-diastolic volume indexed; RVESVi, right ventricular end-systolic volume indexed; RVEF, right ventricular ejection fraction; LVEF, left ventricular ejection fraction; RV:LV, right ventricular:left ventricular; RVp, right ventricular pressure; VO₂, aerobic capacity; ECG, electrocardiogram.