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Introduction:CongenitalCardiovascularAnomalies:MerckManualProfessional06/04/200711:21AM

SECTIONPediatrics

SUBJECTCongenitalCardiovascularAnomalies

Introduction

(SeealsoValvularDisorders.)

Congenitalanomaliesoftheheartandbloodvesselsariseduringthe1st10wkof

embryonicdevelopmentandarepresentatbirth.Theincidenceis1/120livebirths;

estimatedriskis2to3%inchildrenwithanaffected1st-degreerelative.

About5%ofpatientshaveachromosomalabnormality(eg,trisomy13,18,or21,Turners

syndrome);otheranomaliesmaybepartofageneticsyndrome(eg,Holt-Oramsyndrome).

Otherpossiblecausesarematernalillnesses(eg,diabetesmellitus,SLE,rubella),

environmentalexposure(eg,tothalidomide,isotretinoin,oralcohol[fetalalcohol

syndrome]),oracombination.Usually,nospecificcauseisidentified.

Pathophysiology

Congenitalheartanomaliesareclassifiedasacyanoticorcyanotic,andacyanotic

anomaliesareclassifiedasleft-to-rightshuntsorobstructivelesions(seeTable1:

CongenitalCardiovascularAnomalies:ClassificationofCongenitalHeartAnomalies*).

Someanomalies,particularlywhensevere,maycauseheartfailure(HF).

Left-to-rightshunts

Table1

Oxygenatedbloodfromtheleftheart(leftatrium

ClassificationofCongenital

orleftventricle)ortheaortashuntstotheright

HeartAnomalies*

heart(rightatriumorrightventricle)orthe

pulmonaryarterythroughanabnormalopeningClassificationExample

betweenthe2sides.BloodflowsfromlefttoCyanoticTet