Pulmonary hypertension in pregnancy and its effects on the fetus.

Pulmonary hypertension (PH) is an important and potentially lethal diagnosis for pregnant patients. Although pregnancy is usually contraindicated in this condition and there is no standard algorithm for the treatment of pregnant patients with PH, studies in recent years have shown improvement in maternal outcomes for those with PH. Many factors have likely contributed to the improved outcomes, including earlier treatment by multidisciplinary teams. Pregnant patients with PH require specialized management throughout pregnancy, especially in the early post-partum period. Echocardiography is an important diagnostic tool to follow cardiac function in these patients. PH and its treatment during pregnancy has significant implications on maternal as well as fetal outcomes. In this review, PH management during pregnancy and the fetal implications are summarized.

Complicated ventricular arrhythmia and hematologic myeloproliferative disorder in RIT1-associated Noonan syndrome: Expanding the phenotype and review of the literature.

BACKGROUND: Noonan syndrome is an autosomal dominant disorder secondary to RASopathies, which are caused by germ-line mutations in genes encoding components of the RAS mitogen-activated protein kinase pathway. RIT1 (OMIM *609591) was recently reported as a disease gene for Noonan syndrome. METHODS AND RESULTS: We present a patient with RIT1-associated Noonan syndrome, who in addition to the congenital heart defect, had monocytosis, myeloproliferative disorder, and accelerated idioventricular rhythm that was associated with severe hemodynamic instability. Noonan syndrome was suspected given the severe pulmonary stenosis, persistent monocytosis, and "left-shifted" complete blood counts without any evidence of an infectious process. Genetic testing revealed that the patient had a heterozygous c.221 C>G (pAla74Gly) mutation in the RIT1. CONCLUSION: We report a case of neonatal Noonan syndrome associated with RIT1 mutation. The clinical suspicion for Noonan syndrome was based only on the congenital heart defect, persistent monocytosis, and myeloproliferative process as the child lacked all other hallmarks characteristics of Noonan syndrome. However, the patient had an unusually malignant ventricular dysrhythmia that lead to his demise. The case highlights the fact that despite its heterogeneous presentation, RIT1-associated Noonan syndrome can be extremely severe with poor outcome.

Fetal and Postnatal Echocardiographic Diagnosis of Ebstein Anomaly of the Mitral Valve.

Ebstein anomaly of mitral valve (MV) is an extremely rare congenital heart disease. In the current report, we present a case of Ebstein of MV that was diagnosed prenatally. Fetal echocardiogram showed that the posterior leaflet of MV was tethered to the lateral wall of left ventricle (LV) with downward displacement into LV cavity. Postnatal transthoracic and transesophageal echocardiograms confirmed the diagnosis with apical displacement of the level of coaptation MV into the LV cavity. To the best of our knowledge, fetal diagnosis of Ebstein anomaly of MV has not yet been reported in the medical literature.

Acute Pediatric Colchicine Toxicity is Associated with Marked Bradydysrhythmias.

BACKGROUND: Colchicine ingestion is rare but highly lethal. Patients usually die of multiorgan failure and cardiogenic shock. Colchicine is not only associated with depressed myocardial function but also with fatal heart rhythm disturbances, such as complete heart block, ventricular tachycardia, and asystole. While histologic changes of myocytes are well known, the mechanism by which colchicine affects cardiac impulse generation and conduction is not fully understood. CASE REPORT: We present a case of colchicine ingestion with sinus bradycardia, marked sinus arrhythmia, and first- and second-degree heart block. A 10-year-old previously healthy boy was brought to the emergency department for the sudden onset of dizziness, abdominal pain, and vomiting after ingesting his grandfather's colchicine and furosemide. His symptoms improved with ondansetron and intravenous normal saline. However, because of the colchicine ingestion, he was admitted to the pediatric intensive care unit for observation. He first developed PR prolongation (∼4-30 h postingestion) followed by marked sinus bradycardia and sinus arrhythmia along with second-degree heart block (∼48-60 hours postingestion). The minimum heart rate was 40 beats/min. Marked sinus arrhythmia was observed, suggesting an increase in parasympathetic activity. His heart rhythm improved initially with less sinus arrhythmia followed by resolution of heart block. He was discharged home without any sequelae. Holter monitoring 1 week after discharge showed normal heart rate variability for age. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case provides novel insights into how colchicine may affect the heart's electrophysiology. Colchicine may increase the parasympathetic tone enough to cause sinus bradycardia and different degrees of heart block.