Adult Congenital Heart Disease in the Emergency Department

While congenital heart disease historically was a pathology primarily restricted to specialized pediatric centers, advances in technology have dramatically increased the number of people living into adulthood, the number of complications faced by these patients, and the number of patients visiting non-specialized emergency departments for these concerns. Clinicians need to be aware of the issues specific to patients' individual congenital defects but also have an understanding of how typical cardiac pathology may manifest in this special group of patients. This manuscript attempts to provide an overview of this diverse but increasingly common group of adult patients with congenital heart diseases, including a review of their anatomical variants, the complications they face at the highest rates, and ways that emergency physicians may need to manage these patients differently to avoid causing harm.

Natural history of aortic root dilatation and pathologic aortic regurgitation in tetralogy of Fallot and its morphological variants

OBJECTIVE

We sought to characterize the natural history of aortic root dilatation and aortic regurgitation in tetralogy of Fallot (TOF).

METHODS

A single-center review of patients who underwent TOF repair from January 1960 to December 2022 was performed. Morphology was categorized as TOF-pulmonary stenosis or TOF-variant (including TOF-pulmonary atresia and TOF-pulmonary atresia-major aortopulmonary collateral arteries). Echocardiographically determined diameters and derived z scores were measured at the annulus, sinus of Valsalva, and sinotubular junction immediately before TOF repair and throughout follow-up. Linear mixed-effects models assessed trends in dimensions over time.

RESULTS

Of 2205 patients who underwent primary repair of TOF at a median age of 4.9 months (interquartile range, 2.3-20.5 months) and survived to discharge, 1608 (72.9%) patients had TOF-pulmonary stenosis and 597 (27.1%) patients had TOF-variant. At a median postoperative follow-up of 14.4 years (interquartile range, 3.3-27.6 years; range, 0.1-62.6 years), 313 (14.2%) patients had mild or greater aortic regurgitation and 34 (1.5%) patients required an aortic valve or root intervention. The overall mean rates of annular, sinus of Valsalva, and sinotubular junction growth were 0.5 ± 0.2, 0.6 ± 0.3, and 0.7 ± 0.5 mm/year, respectively. Root z scores remained stable with time. At baseline, patients with TOF-variant had larger diameters and z scores at the annulus, sinus of Valsalva, and sinotubular junction, compared with patients with TOF-pulmonary stenosis (all P values < .05). Over time, patients with TOF-variant demonstrated relatively greater annular (P = .020), sinus of Valsalva (P < .001), and sinotubular junction (P < .001) dilatation. Patients with ≥75th percentile root growth rates had a higher incidence of mild or greater aortic regurgitation (P < .001), moderate or greater aortic regurgitation (P < .001), and aortic valve repair or replacement (P = .045).

CONCLUSIONS

Patients with TOF-variant are at comparatively greater risk of pathologic root dilatation over time, warranting closer longitudinal follow-up.

Vascularisation for cardiac tissue engineering: the extracellular matrix

Cardiovascular diseases present a major socio-economic burden. One major problem underlying most cardiovascular and congenital heart diseases is the irreversible loss of contractile heart muscle cells, the cardiomyocytes. To reverse damage incurred by myocardial infarction or by surgical correction of cardiac malformations, the loss of cardiac tissue with a thickness of a few millimetres needs to be compensated. A promising approach to this issue is cardiac tissue engineering. In this review we focus on the problem of in vitro vascularisation as implantation of cardiac patches consisting of more than three layers of cardiomyocytes (> 100 μm thick) already results in necrosis. We explain the need for vascularisation and elaborate on the importance to include non-myocytes in order to generate functional vascularised cardiac tissue. We discuss the potential of extracellular matrix molecules in promoting vascularisation and introduce nephronectin as an example of a new promising candidate. Finally, we discuss current biomaterial- based approaches including micropatterning, electrospinning, 3D micro-manufacturing technology and porogens. Collectively, the current literature supports the notion that cardiac tissue engineering is a realistic option for future treatment of paediatric and adult patients with cardiac disease.

Cardiovascular Z-scores in fetuses with tetralogy of Fallot

OBJECTIVE

To establish formulae for the calculation of fetal cardiovascular Z-scores based on femur length (FL), and to compare cardiovascular parameters between fetuses with tetralogy of Fallot (TOF) and normal fetuses in order to assess their value for the prenatal diagnosis of TOF.

METHODS

A total of 329 normal fetuses and 43 fetuses with TOF were included in this study. Eleven cardiovascular dimensions were measured offline after cardiac spatiotemporal image correlation volume acquisition. Normal cardiovascular Z-score formulae were constructed for these measurements based on FL by performing a standard regression analysis followed by weighted regression of absolute residual values. The following ratios were calculated: right ventricular internal diameter (RVID) to left ventricular internal diameter (LVID) and pulmonary artery diameter (PA) to aorta diameter (Ao). Subsequently, all parameters were compared between the normal and TOF groups.

RESULTS

Formulae for calculating Z-scores for the 11 cardiovascular dimensions were constructed. FL was significantly correlated with all cardiovascular dimensions assessed (r = 0.816-0.944, P < 0.001 for all). RVID, Ao, PA, aortic arch isthmus, and ductus arteriosus mean Z-scores and PA/Ao ratio were statistically significantly different between normal fetuses and those with TOF. In the TOF group, all Ao Z-scores (43/43) were > + 2 and all PA/Ao ratios (43/43) were below the normal 95% range. However, only 48.8% (21/43) of the PA Z-scores were < -2.

CONCLUSIONS

The cardiovascular Z-score formulae developed can provide a quantitative basis for the prenatal diagnosis of TOF. Aortic dilatation and abnormal PA/Ao ratio may be markers for the antenatal diagnosis of TOF.