Mortality in hypoplastic left heart syndrome: Review of 216 autopsy cases of aortic atresia with attention to coronary artery disease

Abstract

Objectives: Aortic atresia (AA) in hypoplastic left heart syndrome (HLHS) has been associated with increased mortality in several prior studies. We reviewed our autopsy series to explore the relationship of coronary abnormalities to anatomic subsets of HLHS with AA. Methods:We retrospectively reviewed all pathology specimens with AA/MS (mitral stenosis) and AA/MA (mitral atresia) in the Cardiac Registry of Children's Hospital Boston between 1955 and 2009 including autopsy reports, operative notes, and imaging studies. Formalin-fixed hearts were examined, and cases found to have macroscopic coronary artery abnormalities were sectioned at mid-left ventricular level in the transverse plane and at mid-right ventricular level in the longitudinal plane for histologic analysis of coronary arteries using tissue sections stained with hematoxylin and eosin.Results: A total of 216 autopsy cases were identified with AA/MS (134) and AA/MA (82). Coronary anomalies were found in 49 cases, left ventricle-coronary fistula in 39, all in AA/MS, and 10 other coronary abnormalities, all in AA/MA. Histologic study confirmed fistulas only in the AA/MS group with no evidence of fistulas in the AA/MA group. Conclusions:The occurrence of left ventricle-coronary fistulas appears limited to the AA/MS group, and coronary fistula specimens were disproportionately more prevalent in postoperative specimens. Further clinical studies are required to validate this finding and to identify subgroups that carry a higher mortality risk.

Coronary Artery Anatomy in Congenital Heart Disease

“…79 As such, VCACs are well described in hypoplastic left heart syndrome (HLHS), particularly among the anatomic subset resulting in hypertension of the hypoplastic LV (e.g., mitral stenosis/aortic atresia [MS/AA]). In a 85 The MS/AA group demonstrated the greatest frequency of anomalies (13-60%, increasing by surgical era), all of which consisted of VCACs (one RV-to-coronary communication, the remainder LV-to-coronary communications). Conversely, there were no VCACs noted among those with mitral atresia/AA; the only arterial anomalies in this group pertained to origin or proximal course (12% overall, consisting of anomalous origin of the left coronary artery from the PA, single coronary artery in three [one with an atretic left coronary ostium], aneurysmal RCA, high takeoff and intramural RCA, intramyocardial LAD, coronary ostial stenosis, hypoplastic coronaries, and high takeoff and oblique ostium of LCA).…”

“…Historically, these connections have been described by a variety of terms used interchangeably (e.g., coronary artery fistulas, myocardial sinusoidal‐coronary arterial connections, ventriculocoronary connections, and myocardial sinusoids) . While coronary‐cameral fistulas have been encountered in the setting of an isolated atrial septal defect (ASD), VSD, or TOF, it is possible that the VCACs encountered in the setting of a hypertensive and hypoplastic ventricle represent an etiologically, histopathologically, and prognostically discrete subtype of fistulous connections, separate even from myocardial sinusoids …”

“…In a recent single‐center series of 214 HLHS patients spanning over five decades, Nathan et al. described notable differences between the different subtypes of HLHS . The MS/AA group demonstrated the greatest frequency of anomalies (13–60%, increasing by surgical era), all of which consisted of VCACs (one RV‐to‐coronary communication, the remainder LV‐to‐coronary communications).…”

“…Overall, HLHS patients with MS/AA have a higher incidence of VCACs and a potentially poorer prognosis than other anatomic subgroups . Nonetheless, while it is possible that these connections negatively impact prognosis in HLHS, the impact of VCACs on mortality in HLHS has not been conclusively established . In contrast to PA‐IVS (for which VCACs clearly impact mortality), HLHS patients with MS/AS generally do not demonstrate proximal coronary obstruction/atresia, rendering significant interference with the coronary circulation less likely .…”

“…[81][82][83] While coronarycameral fistulas have been encountered in the setting of an isolated atrial septal defect (ASD), VSD, or TOF, 79,81 it is possible that the VCACs encountered in the setting of a hypertensive and hypoplastic ventricle represent an etiologically, histopathologically, and prognostically discrete subtype of fistulous connections, separate even from myocardial sinusoids. 41,79,84,85 Microscopically, a VCAC is a thick-walled structure resembling vasculature that connects between an intertrabecular space in the ventricle and a main coronary artery. 81,86 There is often severe coronary artery pathology at the site of the connection, and distal or proximal coronary artery narrowing or even occlusion may also exist.…”