Acute nicotine administration increases BOLD fMRI signal in brain regions involved in reward signaling and compulsive drug intake in rats.

BACKGROUND: Acute nicotine administration potentiates brain reward function and enhances motor and cognitive function. These studies investigated which brain areas are being activated by a wide range of doses of nicotine, and if this is diminished by pretreatment with the nonselective nicotinic receptor antagonist mecamylamine. METHODS: Drug-induced changes in brain activity were assessed by measuring changes in the blood oxygen level dependent (BOLD) signal using an 11.1-Tesla magnetic resonance scanner. In the first experiment, nicotine naïve rats were mildly anesthetized and the effect of nicotine (0.03-0.6 mg/kg) on the BOLD signal was investigated for 10 min. In the second experiment, the effect of mecamylamine on nicotine-induced brain activity was investigated. RESULTS: A high dose of nicotine increased the BOLD signal in brain areas implicated in reward signaling, such as the nucleus accumbens shell and the prelimbic area. Nicotine also induced a dose-dependent increase in the BOLD signal in the striato-thalamo-orbitofrontal circuit, which plays a role in compulsive drug intake, and in the insular cortex, which contributes to nicotine craving and relapse. In addition, nicotine induced a large increase in the BOLD signal in motor and somatosensory cortices. Mecamylamine alone did not affect the BOLD signal in most brain areas, but induced a negative BOLD response in cortical areas, including insular, motor, and somatosensory cortices. Pretreatment with mecamylamine completely blocked the nicotine-induced increase in the BOLD signal. CONCLUSIONS: These studies demonstrate that acute nicotine administration activates brain areas that play a role in reward signaling, compulsive behavior, and motor and cognitive function.

Impact of Digoxin Use on Interstage Outcomes of Single Ventricle Heart Disease (From a NPC-QIC Registry Analysis).

Digoxin has been associated with lower interstage mortality (ISM) following stage 1 palliation (S1P). Despite a substantial increase in digoxin use nationally, ISM has not declined. We aimed to determine the impact of digoxin on ISM in the current era. This study analyzed data from the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry. All patients who survived to hospital discharge following S1P were included. Comparisons were made between pre-specified eras (1: 2010-2015, 2: 2016-2019) based on digoxin use. ISM risk was estimated using the previously published NEONATE score (excluding digoxin). Multivariable Cox proportional hazard models assessed the impact of digoxin on ISM and freedom from unplanned readmission in era 2. A total of 1400 (46.8%) patients were included from era 1 and 1589 (53.2%) from era 2. Digoxin use (22.4% vs 61.7%, p < 0.001) and the proportion of high-risk patients (9.1% vs 20.3%, p < 0.001) increased across eras. There was no difference in predicted ISM risk between those who did vs did not receive digoxin in era 2 (p = 0.82). In era 2, digoxin use was independently associated with lower ISM (AHR 0.60, 95%CI 0.36 to 0.98, p = 0.043) and greater freedom from unplanned readmission (AHR 0.44, 95%CI 0.32 - 0.59, p < 0.001). In conclusion, digoxin is independently associated with lower ISM and greater freedom from interstage readmission. The lack of improvement in overall ISM in the current era may be secondary to a greater proportion of high-risk patients and/or disproportionately higher digoxin use in lower risk patients, who may not derive the same benefit.

HeartMate 3 in a ccTGA patient.

A 49-year-old female with congenitally corrected (or levo-) transposition of the great arteries complicated by nonischemic cardiomyopathy presented for worsening heart failure despite guideline-directed medical therapy and was found to be in cardiogenic shock. She successfully underwent ventricular assist device placement with a HeartMate III to her systemic right ventricle as a bridge to transplantation.

Evaluation of a Screening Program to Detect Critical Congenital Heart Defects in Newborns.

OBJECTIVES: To report the results of and to identify problems with implementing a screening program to detect critical congenital heart defects (CCHDs) in newborns by using differential pulse oximetry (POx). METHODS: Charts of all live-born infants from 4 Yale-New Haven health system hospitals in Connecticut between January 1 and December 31, 2014, were reviewed. RESULTS: Of 10 589 newborns, 171 (1.6%) underwent an echocardiogram before screening, 10 320 (97.5%) were screened by POx, and 98 (0.9%) were not screened. Thirteen newborns (0.1%) were diagnosed with a CCHD. No infants with CCHDs were identified through POx screening (POxS) alone. Eleven (85%) were already suspected of having a CCHD lesion on the basis of prenatal ultrasound, 1 (8%) was diagnosed because of clinical concern before undergoing screening, and 1 (8%) had a false-negative screening result, but a CCHD was identified after an echocardiogram was performed because a murmur was heard. Four infants with a positive POx screen showed noncritical cardiac lesions by echocardiogram. The majority of infants were screened within the recommended 24 to 72 hours of age interval and had POx screens that were interpreted and documented correctly. Of 10 316 infants with negative POx screens, 52.1% were still in the Yale-New Haven Hospital health system at 1 year of age and no CCHD lesions were listed in their charts. CONCLUSIONS: Although a CCHD screening program was effectively implemented, perhaps because most children with a CCHD (85%) were detected antenatally by ultrasound, in our hospital system POxS did not lead to a substantial increase in the early identification of CCHDs.