![]() CATEGORIES: BiologyChemistryConstructionCultureEcologyEconomyElectronicsFinanceGeographyHistoryInformaticsLawMathematicsMechanicsMedicineOtherPedagogyPhilosophyPhysicsPolicyPsychologySociologySportTourism |
Congenital Heart DiseaseDefinition:- - Anomalies of heart and large vessels development due to embriogenesis disturbances during 2-8th weeks of pregnancy
Epidemiology :- - Frequency - 1% - 50-70 % die before 1 year of age (if without surgery) - Only ½ of cases are diagnosed in maternity house; 93% - before 1st year - More than 40 defects are described; 8 are most common (80%)
Most common defects :- - Ventricular septal defect (VSD) - Atrial septal defect (ASD) - Patent ductusarteriosus (PDA) - Coarctation of aorta (CA) - Stenosis of aorta (SA) - Transposition of magistral vessels (TMV) - Fallot’s tetralogy (FT)
Etiology – 1:- - Viral infections (rubella, URIs, mumps, chickenpox) - Radioactive rays - Drugs (thalidomide) - Toxicosis of pregnancy - Starving - Polyhypovitaminosis
Etiology – 2:- - Some diseases of pregnancy (diabetes, heart diseases) - Chromosomal diseases (Down’s syndrome, Marfan’s syndrome, Turner’s syndrome…) - Mother’s age over 35 years - Maternalalcoholconsumption - Family history of a cardiac or noncardiac defect
Classification – I:- - With left-to-right shunting (↑ pulmonary circulation) - With right-to-left shunting (↓ pulmonary circulation) - Without shunting
With left-to-right shunting:- - Ventricular septal defect - Atrial septal defect - Patent ductusarteriosus
With right-to-left shunting:- - Transposition of magistral vessels - Fallot’s tetralogy - Left heart hypoplasia
Without shunting:- - Coarctation of aorta - Stenosis of aorta - Stenosis of pulmonary artery
Classification – II:- - With increase of pulmonary circulation - With decrease of pulmonary circulation With decrease of greater systemic circulation - Without hemodynamic disturbances - ___________ - With or without cyanosis Echocardiography:- - 3-dimensional (3D) echocardiographic images with a Doppler system with superimposing a color-coded direction and velocity of blood flow on the real-time images
Ventricular septal defect:- - Most common: 17-30 % - Size:0.1 cm – 3 cm - Localization: in membranous or muscular part - Delayed diagnosis: first months pulmonary pressure is higher → no cardiac murmur
Ventricular septal defect:- - Small VSD: no significant hemodynamic derangement; loud murmur; can close spontaneously (in muscle segment) - Large VSD: progressively leads to higher pulmonary resistance → irreversible pulmonary vascular changes, so-called Eisenmenger syndrome (reversal of shunt to right-to-left shunt)
Clinics:- - Mild defect: recurrent upper respiratory infections, effort intolerance and fatigue - Severe defect: - Development deficit, failuretothrive - CHF - Pulmonary hypertension
Clinics in early infancy:- - Dyspnea - Feedingdifficulties - Poorgrowth - Profuseperspiration - Recurrentpulmonaryinfections - Cardiacfailure
Physical exam:- - Rough pansystolic murmur in 3-4th intercostal space on the left border of sternum - Accent of S2 over pulmonary artery (pulmonary hypertension) - Left and right ventricular enlargement (palpable parasternal lift, laterally displaced apical impulse, widened heart borders)
ECG:- - Small VSD → Normal - Moderate VSD → signs of LV volume overload (deep Q and tall R waves with tall T waves in leads V5 and V6), LA overload (broad P wave), atrial fibrillation - Severe VSD → right ventricular hypertrophy, with further progression - biventricular hypertrophy
Chest X-ray:- - Small VSD → Normal - Moderate VSD → Increased cardiac silhouette, increased pulmonary vascular markings - Severe VSD → Markedly prominent main PA and adjacent vessels, RV hypertrophy
Medical management:- - Increasedcalories of feedings - Diuretics (furosemide 1-3 mg/kg/d ) - Captopril (0.1-0.3 mg/kg every 8 h) to reduce systemic and pulmonary afterload - Digoxin (5-10 mcg/kg/d) - if diuresis and afterload reduction do not relieve symptoms adequately.
SurgicalCare:- - Transcatheterclosure - Surgicalclosure - Indicationsforsurgicalrepair: - Uncontrolled CHF - Large, asymptomatic defects associated with elevated PA pressure - Pulmonary to systemic flow greater than 2:1. - Prolapseofanaorticvalve
Complications:- - Eisenmengercomplex - Secondaryaorticinsufficiency - Aorticregurgitation - RV outflowtractobstruction - Subaorticobstruction - Infective endocarditis (antibiotic prophylaxis with dental or surgical procedures)
Prognosis:- - 25 % - spontaneous closure (mostly during the first 2 years of life, can be in adults) - 7% of infants with large defects and congestive heart failure - also spontaneous closure - Among small defects, 80% of muscular VSDs closed and 35% of membranous - 10 % - death during 1st year of life - Mean life expectancy – 40 years
Atrial septal defect:- - Frequency: 8-15 % - Size:small – to complete absence - Open oval window → no clinics (30% of adults) - Diagnosis at 1st year – only 40% of cases
Clinics:- - Rarelysymptomatic - Decreasedexercisetolerance - Large shunt → fatigue, dyspnea and arrhythmias
Physical exam:- - Moderate systolic murmur in 2nd intercostal space on the left border of sternum - Accent of S2 over pulmonary artery (pulmonary hypertension) - Signs of cardiac enlargement
ECG:- - Right ventricular hypertrophy (lengthened PR interval and incomplete right bundle branch block) - Atrialenlargement(P wave)
Chest x-ray:- - Prominentrightatrium - Prominentmainpulmonaryartery - Increased heart size and pulmonary vascularity
Complications:- - Sinusnodedysfunction - Pulmonaryvenousobstruction - Atrialfibrillation - Pulmonaryhypertension - Pericardial effusion or post-pericardiotomy syndrome
Prognosis:- - Poor if CHF at early age - Mean life expectancy – 40 years - Best time for surgery – 1st two decades of life - No Px for septic endocarditis
Patent ductusarteriosus:- - Frequency: 10-25 % - Prematures: 50-80% - Normal finding at 1st week of life - Ductus between descending aorta and pulmonary artery bifurcation
Clinics:- - Repeated respiratory infections - Later – liver enlargement, cyanosis - Growth retardation - Septic endocarditis - CHF
Physical exam:- - Loud systolic or systolic-diastolic murmur in the 2nd intercostal space left from sternum - 1st sound accent over pulmonary artery - Murmur diminishes at deep breath-in - Murmur disappears with pulmonary hypertension → appears again with shift reverse
Chest X-ray:- - LV enlargement; later + RV enlargement - Prominent pulmonary vessels
Management:- - Can be closed with indometacin prescription (PG E2 & I2 synthesis inhibitor) – 0.1 mg/kg q8h IV first 8-14 days of life - Surgery best after 6 months but before severe pulmonary hypertension
Prognosis:- - Many defects will spontaneously close before 6 mo of age - Without surgery mortality is 20% - Mean life expectancy is 35 years
Coarctation of aorta:- - 5-8% ofallcongenitalheartdefects - May occur as isolated defect or in association bicuspid aortic valve, ventricular septal defect and others
Clinics:- - Infants – CHF (acute afterload increase after ductusarteriosus closure) - Older children – hypertension (enough time for collaterals development) - Left ventricle overwork → increased wall stress and compensatory ventricular hypertrophy
Physical exam:- - Blood pressure discrepancies between upper and lower extremities - Reduced or absent lower extremity pulses - Differential cyanosis (pink upper extremities with cyanotic lower extremities) - rare - Murmur: nonspecific, under the left scapula
Chest X-ray:- - Early onset of CoA: cardiomegaly, pulmonary edema, and other signs of CHF. - Late onset of CoA: cardiomegaly, arch indentation in the area of the coarctation, and rib notching
ECG:- - Early onset of symptoms: RV rather than LV hypertrophy and evidence of ischemia. - Late onset of symptoms: LV hypertrophy and signs of LV ischemia or strain.
Other tests:- - Preductal and postductal pulse oximetry readings - Cardiac catheterization (evaluation and possible balloon aortoplasty)
Management:- - Prostaglandin E1 (0.05-0.15 mcg/kg/min) IV to open the ductusarteriosus - Treatment of hypertension (beta-blockers and vasodilators) - Treatment of CHF and shock in infants
Surgery:- - End-to-endanastomosis - Patchaortoplasty - Left subclavian flap aortoplasty (left subclavian artery is brought back toward the left carotid artery to enlarge an area of transverse arch hypoplasia)
Complications:- - Hypertension - Intracranialhemorrhageand aneurysms - Aorticruptureordissection - CHF - Recurrentcoarctationafter surgery - Aortic aneurythm - Paralysis(spinal cord ischemia) - Cardiomyopathy
Prognosis:- - Meanlife expectancy is 35 years - Without surgery 1-st year mortality is 25% - Requires bacterialendocarditisprophylaxis
Transposition of magistral vessels:- - Aorta comes from RV and pulmonary artery comes from LV → 2 separated circulations - No disturbance of fetal circulation - Postnatal life is only possible with blood shunts (VSD, ASD, PDA)
Clinics:- - Early total cyanosis from birth, not responsive to oxygen - Tachycardia, tachypnoe, decreased BP - Developmental deficit - CHF by 1st-2nd month of life
Physical exam:- - Murmurs – due to other defects (VSD, ASD, PDA) - Cardiac borders widening
Chest X-ray and ECG:- - Signs of RV (or both) hypertrophy
Management:- - Urgent surgery!
Prognosis:- - 95% die during 1st year of life without surgery - Mean life expectancy is 3 months
Fallot’s tetralogy:- - Most common among cyanotic heart defects - Right-to-left shunt
Defects of TOF:- - Ventricularseptaldefect - Dextrapositionoftheaorta - Obstruction of the right ventricular outflow tract (PA stenosis) - Rightventricularhypertrophy - Pentade: + Atrial septal defect - Triade: no VSD, shunt through Open oval fenestra
Clinics:- - 4 phases: - “Relative stable well-being” - “Gray attacks” - “Blue attacks” - “Stabilization of the condition”
“Relative stable well-being”:- - First 4-6 weeks of life - PDA & Physiologic polycytemia → mild clinics and mild murmur (if any)
“Gray attacks”:- - First 2-9 months of life - Hypoxic attacks after physical strains (feeding, anxiety) – 20-25 times per day - No cyanosis - No complaints between attacks - Failure to thrive
“Gray attacks” - Hypoxic attacks:- - Sudden dyspnoe - Grayish skin color - Crying - Short-period loss of consciousness - Short-period seizures
“Blue attacks”:- - 9 months – 3-5 years of life or all life long - Systemic cyanosis first at attacks, then permanent - Drumstick fingers - Polycytemia - Polyhlobulinemia - Paresis and palsies (brain hemodynamics disturbances)
“Blue attacks” - Hypoxic attacks:- - Involuntary position (knees at chest, older – squatting down): aortic pressure is increased → better shunt to pulmonary artery - Cyanosis and dyspnea
“Stabilization of the condition”:- - After 3-5 years: - Permanent cyanosis, but without attacks - Tachypnea at rest - Murmus is less - ECG, X-ray, Echo - worse
Physical exam:- - Murmur of VSD - Decreased 2nd sound over pulmonary artery
ECG:- - Rightventricularhypertrophy - Left ventricular overload and some left ventricular enlargement - Right atrial enlargement may also be present
Chest X-ray:- - Aneurysmally dilated central pulmonary arteries with otherwise normal peripheral pulmonary vascularity. - Cardiomegaly results from dilation of the right ventricle, particularly its outflow tract (infundibulum) - Appearance of “boot”
Management:- - Attacks – position, oxygen, sedatives - Surgery!
Prognosis:- - Without surgery – 75% mortality before 2 years of age
Date: 2015-01-11; view: 1483
|