Development of a biventricular conversion program: A new paradigm.

BACKGROUND: Borderline small ventricular size or technical issues precluding the use of both ventricles may lead to single ventricle palliation. Fontan complications have led some centers to look for alternatives to the traditional pathway. The objective of this study is to evaluate the essential philosophy and outcomes of a new biventricular (BiV) conversion program. METHODS: The prospectively collected Children's Memorial Hermann Heart Institute Society of Thoracic Surgeon's Database was retrospectively reviewed between July 2017 and July 2020. RESULTS: Thirteen patients met inclusion criteria and underwent BiV conversion during that time. The most frequent diagnosis was malposed great arteries and a ventricular septal defect (VSD) in 4 (31%) patients. Seven (54%) patients were in the first interstage, and 1 (8%) patient had already undergone a Fontan operation before their BiV conversion operation. One or more risk factors for single ventricle palliation (genetic syndrome ≥ moderate atrioventricular valve regurgitation ≥ moderate ventricular dysfunction, presence of signs of Fontan failure) were present in 3 (23%) patients. The median left ventricular end diastolic pressure increased from 5.5 mmHg (4-10 mmHg) to 10 mmHg (6-20 mmHg) postoperatively (p < .05). The right ventricular pressure (RVP) was estimated as less than half systemic in all six patients who were able to be estimated. At a median follow-up of 22.6 months (0.3-36.4 months), 12 (92%) patients are alive. CONCLUSIONS: BiV conversion is feasible with reasonable short-term clinical outcomes. Mortality risk is low, but as seen in other studies, the risk of reintervention is high.

Vascular effects of a single bout of electronic cigarette use.

Electronic cigarettes (EC) are commonly marketed as a safe alternative to traditional tobacco cigarettes (TC), but recent studies have observed adverse effects on vascular functions from EC vapours similar to those observed from TC. Currently, it is not clear if differing levels of nicotine and compounds from heating in e-cigarettes influence vascular functions. Sixteen young, apparently healthy tobacco product naïve participants were studied. Each participant underwent three separate "vaping" trials with menthol-flavoured quit smoking aid, electronically heated menthol-flavoured EC with 0% or 5.4% nicotine. During each visit, measurements were performed at baseline, immediately post, 1, and 2 h post-EC exposure. There were no significant changes in heart rate, systolic and diastolic blood pressure, endothelial function (via flow-mediated dilation), and arterial stiffness (via cardio-ankle vascular index) throughout the experiments. In conclusion, vaping electronic cigarettes did not produce acute and persistent effects on subclinical vascular functions over the course of a 2-h trial in young, healthy, tobacco product naïve participants.