Comparability of Z-score equations of cardiac structures in hypoplastic left heart complex

Hybrid palliation to promote growth of left ventricle and left ventricular outflow tract

OBJECTIVES

In patients with borderline left hearts or a severe left ventricular outflow tract obstruction, hybrid palliation can be used to stabilize the patient and postpone biventricular repair (BVR). In this study, we analysed growth of left-sided structures and outcomes of these patients.

METHODS

We conducted a retrospective cohort study including patients who received hybrid palliation between January 2010 and September 2023. Echo measurements were collected at hybrid palliation, BVR and last follow-up. Growth of left ventricular structures were analysed.

RESULTS

In 38 patients, hybrid palliation was used to promote growth of left ventricular structures. In total, 15 patients received a Ross-Konno/Yasui procedure, while 23 patients received conventional BVR. In patients with a conventional BVR, a significant increase was found in left ventricular volume indexed by body surface area, Z-score of aortic valve and left ventricular outflow tract between hybrid palliation and BVR. Mitral valve Z-score did not increase significantly. After BVR until follow-up, only increase of the aortic valve Z-scores and left ventricular volume indexed by body surface area was found significant. Of all included patients (n = 38), additional surgical procedures were necessary in 8 patients during the interstage period and 15 patients after BVR. Additional catheter interventions were needed in 14 patients in the interstage period and 15 after BVR. Six patients died, with no mortality in the conventional BVR group.

CONCLUSIONS

Hybrid palliation as part of a staged BVR is a safe and effective initial step and promotes the growth of left ventricular structures in patients with small left-sided heart structures. Close follow-up is mandatory because extra catheter or surgical interventions are frequently needed.

Microbiological Profile and Clinical Characteristics of Bacterial Keratitis with Poor Visual Outcome

Purpose: To compare clinical characteristics between the poor visual outcome (PVO) and good visual outcome (GVO) groups in culture-proven bacterial keratitis.Methods: A total of 230 cases (44 and 186 eyes in the PVO and GVO groups, respectively) of culture-proven bacterial keratitis, treated between January 2007 and December 2020, were reviewed retrospectively. The PVO group included cases with the final best-corrected visual acuity (BCVA) of less than 0.1 and no improvement compared to the initial BCVA. The remaining cases were included in the GVO group. The microbiological profiles, epidemiology, predisposing factors, and clinical characteristics were compared between the PVO and GVO groups, and the risk factors for PVO were analyzed.Results: Staphylococcus spp. and Pseudomonas spp. were common isolates in both the PVO and GVO groups, with no significant differences in the distribution of isolates. There were no significant differences between the groups in terms of sex, seasonal distribution, corneal trauma, and prior topical steroid use, but contact lens wear was significantly less in the PVO group. Significant risk factors for PVO were age ≥60 years (Z = 4.22, two-proportion Z-test), central corneal lesions (Z = 3.80), epithelial defect size ≥5 mm² (Z = 3.74), prior ocular surgery (Z = 3.63), hypopyon (Z = 3.42), previous ocular surface disease (Z = 3.32), and diabetes (Z = 3.12).Conclusions: In patients with bacterial keratitis, PVO was associated with older age, severe initial corneal findings, previous ocular disease history, and diabetes, but not with the causative pathogen itself.

Comparative Clinical Analysis of Polymicrobial and Monomicrobial Bacterial Keratitis

Purpose: We comparatively analyzed the microbiological profiles, predisposing factors, clinical aspects, and treatment outcomes of patients with polymicrobial and monomicrobial bacterial keratitis.Methods: A total of 194 cases of culture-proven bacterial keratitis treated between January 2007 and December 2016 were reviewed. Microbiological profiles, the epidemiology, predisposing factors, clinical characteristics, and treatment outcomes were compared between the polymicrobial group (polymicrobial bacterial keratitis [PBK]; 29 eyes, 62 isolates) and monomicrobial (monomicrobial bacterial keratitis [MBK]; 165 eyes, 165 isolates) group.Results: The most common isolates were Enterobacter (24%) in the PBK group and Staphylococcus (22%) in the MBK group. There were no significant differences between the two groups in previous ocular surface disease, previous ocular surgery, prior topical steroid use, epithelial defect size, and hypopyon. Age ≥60 years (PBK vs. MBK, 31% vs. 51%, p = 0.048), symptom duration (4.7 days vs. 8.0 days, p = 0.009), and contact lens use (34% vs. 18%, p = 0.036) were significantly different between the two groups. Regarding treatment outcomes, epithelial healing time ≥10 days, the final best-corrected visual acuity (BCVA), a need for surgical intervention, and the rate of poor clinical outcome were not significantly different between the two groups. Significant risk factors for a poor clinical outcome in all patients were an initial BCVA <0.1 (Z = 6.33, two-proportion Z-test), an epithelial defect size ≥5 mm2 (Z = 4.56), and previous ocular surface disease (Z = 4.36).Conclusions: Polymicrobial bacterial keratitis, compared to monomicrobial bacterial keratitis, was more significantly associated with younger age, contact lens use, and shorter symptom duration.

Small and borderline left ventricular outflow tract - a perplexing maladie

The left ventricular outflow tract (LVOT) comprises of the subvalvular area, the aortic valve, and the supravalvular region. Obstructive lesion of LVOT is a spectrum with varying levels and degree of obstruction with or without associated hypoplasia of the left ventricle. Decision-making in small and borderline LVOT can be challenging. Imaging modalities such as echocardiography and magnetic resonance imaging and scores based on imaging aid in the decision making in truly borderline cases. Newer treatment strategies like staged left ventricular rehabilitation and hybrid procedure have come to the fore in the past decade or so. Although these do not address small LVOT per se, they delay the decision-making to a more appropriate age. The goal of management in these cases is to achieve a biventricular repair whenever feasible. Several surgical techniques could be employed to achieve this goal. However, it is important to be cognizant of the fact that an overzealous approach to achieve a biventricular repair might be counterproductive. A univentricular palliation could be a safer alternative; especially considering the possibility of a future transplant candidacy.

Detailed Echocardiographic Measurements of Individual Chamber in a Chinese Cohort of Hypoplastic Left Heart Syndrome and Comparison with Normal Fetuses via Z-score Modeling

Hypoplastic left heart syndrome (HLHS) is a rare, but exceptionally serious, congenital heart defect. We aimed to explore the best-fitted Z-score models for individual chamber dimension and to draw a comparison between fetuses with HLHS and the normal Chinese cohort. We made measurements of 1674 healthy fetuses and 79 fetuses with HLHS, undertaking echocardiography. Normal fetal cardiovascular Z-score formulae were established by curve-fitting with 5 algorithmic functions and weighted regression of absolute residuals. Classic linear models were fitted for left ventricular diameter against gestational age, and log-transformed linear-power models-were statistically better for left ventricular length, diameter of left atrium and ascending aorta. Fetuses with HLHS manifested significantly lower Z-score means (≤3.5) for these 4 parameters and the vast majority (∼90%) lay beyond -2. Overall, cardiovascular Z-score equations were reliably constructed in a larger Chinese cohort, and their application should benefit evaluation and diagnosis of HLHS.

Feasibility and safety of biventricular repair in neonates with hypoplastic left heart complex

Hypoplastic left heart syndrome is a spectrum of structural cardiac malformations characterized by variable underdevelopment of the left heart-aorta complex. A minority of patients having a milder degree of left ventricular hypoplasia, described as hypoplastic left heart complex (HLHC), may be selected for biventricular repair. The objective of this study was to assess the outcome of the biventricular approach in HLHC. We evaluated retrospectively 30 neonates diagnosed with HLHC from the "12 de Octubre" University Hospital, following established criteria. We analyzed the echocardiographic data recorded just after birth and at last follow-up after surgery. All patients were operated on in the neonatal period using various surgical techniques. There were no early deaths and only 1 late death after a mean follow-up of 62.9 ± 43.8 months. All patients presented a significant growth of the left ventricular structures, with a Z-score increase of 1.17 ± 1.05 for mitral annulus, 1.72 ± 1.23 for aortic annulus, and 1.33 ± 1.46 for left ventricular end-diastolic diameter. Postoperatively, 18 patients showed a left valvular stenosis, and 17 patients underwent a reoperation and/or an interventional procedure. Freedom from surgery or interventional catheterizations at 1, 3 and 5 years was 53, 49 and 43%, respectively. The 29 current survivors are all in a good functional status. In our experience, we achieved good results from biventricular repair in patients with HLHC, with a significant growth of left heart structures and an excellent clinical status at a medium-term follow-up. Nevertheless, there was a high rate of reoperations and/or interventional catheterizations.

Development of an echocardiographic scoring system to predict biventricular repair in neonatal hypoplastic left heart complex

Neonates born with borderline left heart hypoplasia, or hypoplastic left heart complex, can undergo biventricular repair while those with severe left heart hypoplasia require single ventricle palliation. Deciding which patients are candidates for biventricular repair may be very difficult since there are no scoring systems to predict biventricular repair in these patients. The purpose of this study is to develop an echocardiographic scoring system capable of predicting successful biventricular repair in neonatal hypoplastic left heart complex. The study cohort consisted of twenty consecutive neonates with hypoplastic left heart complex presenting between 9/2008 and 5/2013. Multiple retrospective echocardiographic measurements of the right and left heart were performed. Six patients with significant LH hypoplasia (patent mitral and aortic valves, small left ventricle) who had undergone single ventricle repair were used to validate the scoring system. Seventeen patients underwent biventricular repair and three underwent single ventricle repair. A scoring system (2V-Score) was developed using the equation {[(MV4C/AVPSLA) ÷ (LV4C/RV4C)] + MPA}/BSA. Using a cutoff value of ≤ 16.2, a biventricular repair would have been predicted with a sensitivity of 1.0, specificity 1.0, positive predictive value 1.0, negative predictive value 1.0, area under the ROC curve 1.0, and the p value was 0.0004. The 2V-Score was more accurate than the Rhodes, CHSS, or Discriminant scores in retrospectively predicting biventricular repair in this cohort. The 2V-Score shows promise in being able to predict a successful biventricular repair in patients with hypoplastic left heart complex but requires prospective validation prior to widespread clinical application.

Echocardiographic nomograms for chamber diameters and areas in Caucasian children

BACKGROUND

Although a quantitative evaluation of cardiac chamber dimensions in pediatric echocardiography is often important, nomograms for these structures are limited. The aim of this study was to establish reliable echocardiographic nomograms of cardiac chamber diameters and areas in a wide population of children.

METHODS

A total of 1,091 Caucasian Italian healthy children (age range, 0 days to 17 years; 44.8% female) with body surface areas (BSAs) ranging from 0.12 to 1.8 m(2) were prospectively enrolled. Twenty-two two-dimensional and M-mode measurements of atrial and ventricular chamber diameters and areas were performed. Models using linear, logarithmic, exponential, and square-root relationships were tested. Heteroscedasticity was tested by the White test and the Breusch-Pagan test. Age, weight, height, and BSA, calculated by the Haycock formula, were used as the independent variables in different analyses to predict the mean value of each echocardiographic measurement. The influence of various confounders, including gender, type of delivery, prematurity, and interobserver variability, was also evaluated. Structured Z scores were then computed.

RESULTS

The Haycock formula provided the best fit and was used when presenting data as predicted values (mean ± 2 SDs) for a given BSA and within equations relating echocardiographic measurements to BSA. Confounders were not included in the final models, because they did not show significant effects for most of the measurements.

CONCLUSIONS

Echocardiographic reference values are presented for chamber area and diameters, derived from a large population of healthy children. These data partly cover a gap in actual pediatric echocardiographic nomograms. Further studies are required to reinforce these data, as well as to evaluate other parameters and ethnicities.