Mad-about-pediatriccardiology

What is a Fontan? - palliative surgery which is performed in patients with a functional or an anatomic single ventricle - ventricle which is rudimentary or <30% of the expected volume. What are the typical anatomy for which a Fontan is performed? - HLHS - Tricusid atresia - Unbalanced AV canal - PA/IVS - DILV Rarely it may need to be performed in conditions such as - Ebstein's - DORV - ccTGA - any anatomy where there is severe hypoplasia of one of the ventricles Concept behind a fontan - there is a single ventricle and its job needs to be dedicated to pumping to the systemic circulation - therefore there is passive flow of blood through the Fontan - blood driven by central venous pressure - intra thoracic pressure changes - relaxation of the systemic ventricle 10 COMMANDMENTS FOR A SUCCESSFUL FONTAN PROCEDURE 1. Age - 2-7years of age 2. sinus rhythm 3. Normal systemic venous drainage 4. Normal right atrial volume 5. No/ minimal AVVR 6. Normal sing

ECG interpretation in athletes ECG is very useful for early identification of causes of sudden cardiac death in athletes such as cardiomyopathy, primary electrical diseases. This interpretation becomes even more difficult in athletes where normal physiologic changes related to athletic training (Athlete's heart)  have to be distinguished from pathologic changes.  In 2012 a summit met at Seattle and put together a group of criteria to distinguish Athlete's heart form a pathological ECG findings (check out article at pubmed link http://www.ncbi.nlm.nih.gov/pubmed/23303758). The group discussed about 1. Normal ECG findings in athletes 2. Abnormal findings in cardiomyopathy 3. Abnormal findings in primary electrical  The above table is taken from the Seattle criteria guideline.  Check out the table below which gives you a great summary of abnormal ECG findings

1 1/2 ventricular repair Biventricular repair ----> 1 1/2 ventricular repair ----> Single ventricle / Fontan pathway 1 1/2 repair - concept useful in case of borderline pulmonic ventricles. So the ventricle is not big enough to sustain a biventricular repair and is not small enough to commit the patient to a single ventricle route. Therefore this repair comprises of performing a Glenn procedure to offload the RV as well as intracardiac repair to keep open the future option of switching to a 2 ventricle pathway. http://www.ncbi.nlm.nih.gov/pubmed/9725452 Use the link above to access an excellent paper from Toronto by Dr. Freedom where the criteria for a 1 1/2 ventricle repair is discussed. This can be applied to 3 categories of patients 1. morphologic small pulmonary ventricle 2. functional deficits to the ventricle 3. special circumstances This table is taken directly from the article I was referring to from Toronto. The 1 1/2 ventricle repair has been fou

Glenn with additional sources of pulmonary blood flow - what are the advantages? In some situations the Glenn anastomosis is performed along with an additional source of antegrade pulmonary blood flow, either with 1.  an additional systemic to PA shunt                          OR  2. Banding main pulmonary artery (Pulsatile Glenn). What are the advantages? 1. The pulmonary vascular bed is exposed to pulsatile pulmonary blood flow. According to certain studies exposing the pulmonary bed to this pulsatility improves growth of pulmonary vasculature pre-Fontan 2. Improved post operative SaO2. This effect may be negated in the long term where patients with only Glenn procedure may develop AP collaterals over time which causes their SaO2 to increase 3. The pulmonary vasculature is exposed to hepatic factor from the liver and therefore theoretically there is a lower likelihood of developing AP collaterals. What are the disadvantages? 1. The Glenn pressure is elevate

RSV bronchiolitis Causes 50-90% of all bronchiolitis in the US risk factor - young infants <1year ( esp 1-2month old)                     congenital heart disease                     premature babies                     patients with chronic lung disease                     neuro-muscular disease / congenital airway abnormalities Rate of hsopitalization is almost 5% for every 100,000 children Risk of CPAP and mech ventilation with premature infants and patients with hemodynamically significant heart disease Treatments such as albuterol, racemic epinephrine has not shown to shorten the duration / change duration of hospitalization of infants with RSV bronchiolitis RSV infection is associated with some degree of myocardial injury as evidenced by increase in troponin I with RSV infections in patients ( Cardiac troponin i as a predictor of respiratory failure in children hospitalized with respiratory syncytial virus (RSV) infections: a pilot study - Checchia Paul et a

status asthmaticus : severe asthma unresponsive to  inhaled beta 2 agonists oral or intra venous steroids oxygen bronchospasms, airway constriction, M3 receptors stimulation , tachykinin secretion ---> leads to expiration becoming an active process End expiratory volume increases  Diaphragmmatic flattening from hyperinflation causes additional mechanical disadvantages FEV and FVC are decreased, FRC is increased. pulsus paradoxus : fall in SBP with inspiration - neg intrathoracic pressure, ideally the BP should fall.  leukocytosis ---> infection/ demargination hypokalemia ---> to be expected given continuous beta agonists hypomagnesemia : should be corrected --> has better prognosis all children with first time wheezing and severe status asthmaticus require a chest x ray inhaled beta agonists may nullify the compensatory pulmonary vasocontstriction response and worsen arterial hypoxemia, so O2 must be a part of all asthma treatment