Disclosures. Practical Aspects of Pediatric Cardiology for the General Practitioner. Objectives. Outlines. CCHD Neonatal Screening

Transcription

1 Practical Aspects of Pediatric Cardiology for the General Practitioner Majd Makhoul, MD 48 th Annual Family Medicine Review and Contemporary Pediatrics Conference November 11, 2016 Lexington, KY None Disclosures Objectives Outlines Discuss the usefulness and limitations of Critical Congenital Heart Defects screening (CCHD) in the newborn. Describe common Pediatric EKG normal variants and abnormalities. CCHD screening history and algorithm. Cases of CCHD detected by screening. Cases of CCHD missed by screening. Quick guide to read peds EKG. Normal pediatric EKG variants. Cases of common abnormal peds EKG. CCHD Neonatal Screening Audience Response Question 1

2 Which one of the following 1 st CCHD screening attempts is considered positive/failed? A. RH = 96%, F = 94%. B. RH = 95%, F = 92%. C. RH = 92%, F = 91%. D. RH = 91%, F = 89%. E. RH = 94%, F = 97%. Background 7,200 babies are born annually with critical congenital heart defects in the US. They often are life threatening and requires intervention in neonatal period. Prenatal US detect about 50% of CCHD cases. Predicting O2 saturation based on visual examination of color is unreliable. Background Overall about 25% of CCHD cases are not diagnosed till after discharge These are often ductal dependent and PDA often does not close till after hours of life. This will likely be at home especially with early discharge. Such babies will have significant deterioration after ductal closure. Implementation Many European countries started screeming in early 2000s. In 2011, HHS Secretary Kathleen Sebelius adopted the recommendations to add newborn screening for CCHD to recommended neonatal screening. AAP, ACC, AHA endorsed that. On April 17, 2013 became the law in KY. KY CCHD Screening Started officially in January 2014 after big educational campaign. 94% of neonates screened in positive tests 15 confirmed CCHDs 97% of neonates screened in positive tests 38 confirmed CCHDs What CCHDs are Reliably Detected Hypoplastic left heart syndrome (HLHS) Pulmonary atresia, intact septum (PA/IVS) Tetralogy of Fallot (TOF) Total anomalous pulmonary venous return (TAPVR) Transposition of the great arteries (TGA) Tricuspid atresia Truncus arteriosus 2

3 What CCHDs Can be Missed Aortic arch atresia or hypoplasia Coarctation of the aorta Double-outlet right ventricle (DORV) Ebstein anomaly Pulmonic stenosis or atresia with VSD False Positive Possibilities PPHN Hemoglobinopathy Hypothermia Sepsis Lung disease Why is it a good idea? Detects treatable asymptomatic conditions. Prevent significant morbidity and mortality. Readily available, painless and cost effective ($14.00 per test). Reliable (False positive screening is about 0.035%). Method All well newborn babies while awake, warm and calm. Use motion tolerant pulse oximetry. Can use reusable or disposable probes. Obtain right hand and either foot sats. After 24 hours of life or as late as possible if discharged before 24 hours of life. Cases 3

4 Case 1 36 hour old baby boy, 3.5 Kg, 50 cm No risk factors Doing well clinically and will go home in AM Had newborn screening for CCHD with following results. Right hand = 91% Right foot = 88% Positive/Failed Test What is next? Born in a facility with direct access to echocardiography and telemedicine access to a pediatric cardiologist. Echo done and showed one of the 5Ts. TGA Next Started on PGE1 and transferred to a congenital CT surgical center. Had arterial switch operation at DOL 4 with no complications. Discharged home at DOL 10. Now is 2 year old and asymptomatic. Another Scenario Baby delivered in a rural hospital. No access to echocardiography. Kentucky Children s is 3 hours away. Baby transferred to KCH and echo done at 46 hours of age. Rest of story is same. Case 2 Baby girl, FTP, NVD. Normal prenatal care and OB US. Slow feeder in nursery. Passes CCHD screening at 36 hours of life. Went home on DOL 2. 4

5 Saw PCP at DOL 3. Still not a great feeder. Found to have ankyloglossia (tongue tie) which was clipped. DOL 5 presented to ER with mild lethargy and increased WOB. Pulses decreased overall. Cardiomegaly on CXR. Elevated lactate so given IV fluid bolus and transferred to PICU. Sepsis workup done too. Echo ordered. Critical coarctation of the aorta & VSD PGE1 started in a trial to reopen the ductus and relax the tight arch. Baby intubated and ventilated. Two hours later clinically better and lactic acidosis clearing. Two days later, LV function normalized and baby had surgery. 5

6 What Did we Do Wrong? Nothing really as long as PCP felt good femoral pulses at DOL 3. This is an example of missed CCHD by CCHD screening test. No significant hypoxemia with this form of CCHD. This is why Coarctation is not included in the 7 CCHDs that we screen for. CCHD Screening; High Tech Mobile website or download the free app. What did we learn about CCHD? CCHD pulse Oximetry Screening is great but not perfect. Keep your clinical suspicion level high. Feeling femoral pulses during newborn evaluation is critical. Which one of the following 1 st CCHD screening attempts is considered positive/failed? A. RH = 96%, F = 94%. B. RH = 95%, F = 92%. C. RH = 92%, F = 91%. D. RH = 91%, F = 89%. E. RH = 94%, F = 97%. Which one of the following EKG findings is abnormal in 2 week old baby? Pediatric EKG A. Heart rate of 180 bpm. B. QRS axis of 120 degrees (rightward axis). C. Upright T wave in lead V1. D. Tall R wave in lead V1. E. Deep S wave in lead V6. 6

7 Systematic Approach Confirm voltage/paper speed Rate and Rhythm Ventricular Axis Intervals Individual Waves Confirm voltage/paper speed Rate and Rhythm Ventricular Axis Intervals Individual Waves Voltage & Paper Speed Standard settings: 1 mv per 10 mm 25 mm/sec Amplitude too low Change to double standard (20mm/1mv). Divide amplitude by 2 when reading. 7

8 Amplitude too high Change to half standard (5mm/1mv). Multiply amplitude by 2 when reading. Rate too fast. Double paper speed (50 mm/sec). Rate calculation changes = 600/large boxes. Rarely need to decrease speed < 25 mm/sec. Confirm voltage/paper speed Rate and Rhythm Ventricular Axis Intervals Individual Waves 8

9 Rhythm is it sinus? P wave for every QRS Stable P wave morphology P wave axis consistent with sinus node origin Upright P wave in leads I and avf Normal Sinus Rhythm Confirm voltage/paper speed Rate and Rhythm Ventricular Axis Intervals Individual Waves QRS Axis QRS Axis Age dependent Newborn have normal R axis Infants can have slightly R axis Superior (left) axis is almost always abnormal 9

10 QRS Axis Look at leads I and avf to determine which quarter. Then find the limb lead with equal negative and positive forces and your axis will be perpendicular to that lead. Confirm voltage/paper speed Rate and Rhythm Ventricular Axis Intervals Individual Waves PR interval QRS duration ST segment QTc interval Intervals PR Interval Age dependent. Gets progressively longer till late teen years. Too long = AV block. Too short =? WPW or atrial rhythm. QRS Duration Usually < 100 msec. > 120 = BBB or ventricular rhythm. V1 and V6 leads are again your friends here. Wider QRS means slower conduction Wider QRS part upward = slower conduction going in same direction of the lead Wider QRS part downward = slower conduction going in opposite direction of the lead 10

11 ST Segment Slight elevation with concave morphology in precordial and inferior leads Early repolarization (NORMAL). More significant ST elevation and diffuse one with chest pain and URI few weeks before PERICARDITIS QTc Bazett s Formula Convex ST elevation or ST depression is usually abnormal and means myocardial involvement. Myocarditis if diffuse Ischemia if localized and usually older folks or drugs. QTc measured from lead II or V5 11

12 QTc Interval Often miscalculated by EKG machines. >470 msec is likely abnormal regardless of gender or age. >500 msec is definitely abnormal. Be aware of drugs and metabolic causes. Long QT syndrome is a cause of SCD. Confirm voltage/paper speed Rate and Rhythm Ventricular Axis Intervals Individual Waves Atrial Enlargement Atrial Enlargement P waves duration and amplitude should be < 2.5 mm in lead II Tall P wave = RA enlargement Wide notched P wave = LA enlargement Ventricular Hypertrophy Ventricular Hypertrophy For ventricular hypertrophy, focus on leads V1 and V6. More muscle in LV = stronger voltage toward V6 = Tall R wave in V6. More muscle in LV = stronger voltage away from V1 = Deep S wave in V1. Reverse it and you get RVH. 12

13 T Wave Abnormalities Peaked Tall T wave = High K. Notched T wave = long QT. Low amplitude T wave = hypokalemia or myocardial abnormalities. T wave in V1 is upright at birth, becomes downward around few days of life and stays like that for a while (6-26 years). Cases 1 day old girl with Hx of fetal arrhythmia 2 week old with tachycardia 8 year old with irregular heart rhythm Normal Variants Axis in neonates is normally rightward. T wave should be inverted in V1 after few days of life. Sinus arrhythmia is a misnomer (normal). 13

14 More Cases 2 months old baby boy. NVD, FTP, no issues. Growing well and no cyanosis (O2 sats = 97%). Harsh SEM at LUSB that radiates to R and L axillae and back. Rest of exam normal. 7 month old with new diagnosis of PNA. Been on Abx for one week with no more fever but still requiring O2 to keep saturation in low 90s. No previous issues but parents not the best historians. Faint systolic murmur on exam and some crackles. Severe Pulmonary Stenosis Complete AV Canal Defect 13 yo boy with chest pain for the last few days. Tired more easily today, poor appetite. No sick contacts but had URI couple weeks ago. Overweight so hard to hear good heart sounds on exam but no obvious murmurs or gallop. Clear lungs, no other findings on exam. 14

15 Goes to local ER. Troponin elevated. CXR with cardiomegaly. Transferred to KCH. Echo done and shows.. Important Peds EKG Abnormalities Upright T wave after few days of life = RV pressure overload. Superior (left) axis is always abnormal (AV canal variant or TA). LVH with T wave abnormalities is highly suggestive for myocardial process. Which one of the following EKG findings is abnormal in 2 week old baby? A. Heart rate of 180 bpm. B. QRS axis of 120 degrees (rightward axis). C. Upright T wave in lead V1. D. Tall R wave in lead V1. E. Deep S wave in lead V6. To Wrap Up. CCHD Pulse Oximetry screening is great but not perfect. Be systematic when reading EKGs and remember kids are not little adults. Come back next year to see us. 15

16 Thank You 16