Identifying Risk Factors for Massive Right Ventricular Dilation in Patients With Repaired Tetralogy of Fallot

https://doi.org/10.1016/j.amjcard.2019.12.016Get rights and content

In repaired tetralogy of Fallot (rTOF), pulmonary insufficiency results in varying degrees of right ventricle (RV) dilation. A subset of patients is diagnosed at initial cardiac magnetic resonance imaging (CMR) with a massively dilated RV, far beyond pulmonary valve replacement (PVR) criteria, which is unlikely to return to normal size after PVR. This study aimed to identify risk factors for massive RV dilation at initial CMR. This nested case-control study included all patients at our institution with rTOF and massive RV dilation (indexed RV end-diastolic volume [RVEDVi] ≥200 ml/m2) on initial CMR. Patients were matched by age at first CMR, gender, and type of repair with rTOF controls with RVEDVi<200 ml/m2. In 39 cases (median RVEDVi 227 ml/m2, interquartile range [IQR] 213 to 250) and 73 controls (median RVEDVi 155 ml/m2, IQR 130 to 169), repair at >6 months of age, longer QRS duration, and non-Caucasian race were significantly associated with massive RV dilation on univariate analysis. In multivariate analysis, repair at >6 months of age (adjusted odds ratio [AOR] 2.90, 95% confidence interval [CI] 1.12 to 7.55, p = 0.03), longer QRS duration (AOR = 1.03, 95% CI 1.01 to 1.05, p = 0.005), and non-Caucasian race (AOR = 7.84, 95% CI 1.76 to 34.8, p = 0.01) remained independently associated with massive RV dilation. Era of repair, history of systemic to pulmonary shunt palliation, genetic anomaly, and additional cardiac lesions did not differ between groups. In conclusion, these risk factors identify a subset of patients who may benefit from earlier CMR evaluation to avoid massive irreversible RV dilation.

Section snippets

Methods

This was designed as a nested case-control study within a retrospective cohort. A center-specific CMR database was reviewed to identify patients with a diagnosis of TOF who underwent their first CMR imaging study at our center between the database's inception in October 2007 through March 2015. Inclusion criteria for the study were a diagnosis of TOF following complete surgical repair and first CMR performed postrepair at our center. Exclusion criteria included PVR before first CMR, unknown

Results

A total of 387 patients with TOF were identified during the study period. Of these, a total of 39 cases were identified and matched to 73 controls, for a total of 112 patients (71% male, median age at CMR 19.8 years, IQR 14.7 to 31.7 years). A flowchart depicting patient identification is shown in Figure 1. Patient, surgical, and clinical characteristics are depicted in Table 1. Additional cardiac lesions included a variety of defects including atrial septal defect, right aortic arch, and

Discussion

In patients with rTOF, age at complete repair >6 months, longer QRS duration, and non-Caucasian race were significantly associated with massive RV dilation at first CMR. An RV size by echo of moderately dilated or greater was sensitive, but not specific, to predict massive dilation on CMR. This population, 10% of the TOF patients referred to CMR at our center in this time period, is unlikely to have their RV return to normal size after PVR. To our knowledge, this is the first study reporting

Disclosures

The authors have no conflict of interest to disclose.

References (49)

  • HX Zhao et al.

    Surgical repair of tetralogy of Fallot. Long-term follow-up with particular emphasis on late death and reoperation

    J Thorac Cardiovasc Surg

    (1985)
  • AF Corno et al.

    Chronic hypoxia: a model for cyanotic congenital heart defects

    J Thorac Cardiovasc Surg

    (2002)
  • T Bove et al.

    Role of myocardial hypertrophy on acute and chronic right ventricular performance in relation to chronic volume overload in a porcine model: relevance for the surgical management of tetralogy of Fallot

    J Thorac Cardiovasc Surg

    (2014)
  • BW Yoo et al.

    Impact of pressure load caused by right ventricular outflow tract obstruction on right ventricular volume overload in patients with repaired tetralogy of Fallot

    J Thorac Cardiovasc Surg

    (2012)
  • N Jones et al.

    Echocardiographic assessment of the right ventricle-state of the art

    Heart Lung Circ

    (2019)
  • ME Oster et al.

    Racial and ethnic disparities in post-operative mortality following congenital heart surgery

    J Pediatr

    (2011)
  • JG Murphy et al.

    Long-term outcome in patients undergoing surgical repair of tetralogy of Fallot

    N Engl J Med

    (1993)
  • HL Lindberg et al.

    Single-center 50 years' experience with surgical management of tetralogy of Fallot

    Eur J Cardiothorac Surg

    (2011)
  • G Nollert et al.

    Long-term results of total repair of tetralogy of Fallot in adulthood: 35 years follow-up in 104 patients corrected at the age of 18 or older

    Thorac Cardiovasc Surg

    (1997)
  • EJ Hickey et al.

    Late risk of outcomes for adults with repaired tetralogy of Fallot from an inception cohort spanning four decades

    Eur J Cardiothorac Surg

    (2009)
  • CA Smith et al.

    Long-term outcomes of tetralogy of Fallot: a study from the pediatric cardiac care consortium

    JAMA Cardiol

    (2019)
  • C van Doorn

    The unnatural history of tetralogy of Fallot: surgical repair is not as definitive as previously thought

    Heart

    (2002)
  • A Borowski et al.

    Severe pulmonary regurgitation late after total repair of tetralogy of Fallot: surgical considerations

    Pediatr Cardiol

    (2004)
  • MY Abd El Rahman et al.

    Relation between right ventricular enlargement, QRS duration, and right ventricular function in patients with tetralogy of Fallot and pulmonary regurgitation after surgical repair

    Heart

    (2000)
  • Cited by (4)

    Clinton Cochran: Conceptualization, investigation, writing – original draft, writing – review and editing. Sunkyung Yu: Methodology, formal analysis, data curation, visualization, writing – review and editing. Lindsey Gakenheimer-Smith: Investigation. Ray Lowery: Data curation, formal analysis, software, investigation. Jimmy Lu: Visualization, writing – review and editing. Maryam Ghadimi Mahani: Visualization, writing – review and editing. Prachi P. Agarwal: Visualization, writing – review and editing. Adam Dorfman: Conceptualization, investigation, methodology, writing – review and editing, supervision, visualization.

    Sources of funding: None.

    View full text