RT Book, Section
A1 Opotowsky, Alexander R.
A2 Daniels, Curt J.
A2 Zaidi, Ali N.
SR Print(0)
ID 1128634215
T1 PULMONARY HYPERTENSION IN ADULTS WITH CONGENITAL HEART DISEASE
T2 Color Atlas and Synopsis of Adult Congenital Heart Disease
YR 2016
FD 2016
PB McGraw-Hill Education
PP New York, NY
SN 9780071749435
LK accesscardiology.mhmedical.com/content.aspx?aid=1128634215
RD 2024/04/18
AB Pulmonary  hypertension  (PH)  itself  is  not  a  disease  and  does  not  specify  any  unique  pathophysiology.  PH  refers  to  elevated  pulmonary  artery  (PA)  pressure.The  underlying  physiology  is  variable  with  a  major  distinction  between  PH  caused  by  elevated  pulmonary  venous  (distal)  pressure,  elevated  pulmonary  vascular  resistance  (PVR),  and  high  flow  (Figure  9-1).1Pulmonary  hypertension  can  be  due  to  any  combination  of  these  3  underlying  physiologies  in  various  types  of  congenital  heart  disease.  Marked  pulmonary  vascular  remodeling  does  not  necessarily  translate  into  elevated  pulmonary  artery  pressure  in  the  setting  of  low  flow.  The  presence  of  dynamic  shunting  complicates  interpretation.  An  acute  increase  in  flow  itself  causes  recruitment  and  dilation  of  pulmonary  vessels,  resulting  in  decreased  pulmonary  vascular  resistance.While  the  equation  for  PVR  (PVR  =  ΔP/CO)  may  suggest  that  PVR  is  equivalent  at  any  flow  (eg,  if  you  double  CO  then  ΔP  will  double  and  therefore  PVR  will  remain  stable),  the  relationship  is  not  linear  (Figure  9-2).  While  this  phenomenon  can  be  important  in  the  absence  of  congenital  heart  disease  (CHD),  its  appreciation  is  critical  in  interpretation  of  hemodynamic  data  in  patients  with  shunting.  Further,  distinct  underlying  etiologies  often  produce  equivalent  physiology  and  indistinguishable  pulmonary  vascular  pathology.Pulmonary  arterial  hypertension  (PAH)  is  defined  as  PH  with  high  PVR  without  pulmonary  venous  hypertension.2This  chapter  will  review  PH  in  adults  with  congenital  heart  disease  from  the  perspective  of  the  underlying  physiology  followed  by  several  cases  which  highlight  dynamic  interplay  between  the  component  parts  of  "pulmonary  pressure"  and  finally  a  discussion  of  special  cases  of  right  heart  pathology  requiring  special  consideration.