RT Book, Section
A1 Madani, Michael M.
A1 Jamieson, Stuart W.
A2 Yuh, David D.
A2 Vricella, Luca A.
A2 Yang, Stephen C.
A2 Doty, John R.
SR Print(0)
ID 1104592297
T1 Surgical Treatment of Chronic Pulmonary Thromboembolic Disease
T2 Johns Hopkins Textbook of Cardiothoracic Surgery
YR 2014
FD 2014
PB McGraw-Hill Education
PP New York, NY
SN 978-0-07-166350-2
LK accesssurgery.mhmedical.com/content.aspx?aid=1104592297
RD 2024/04/20
AB EpidemiologyThe  precise  incidence  of  pulmonary  embolism  (PE)  is  unknown;  it  is  estimated  to  be  in  the  range  of  1  to  3  in  1000  individuals.  Approximately  75  percent  of  autopsy-proven  PEs  are  not  detected  clinically.  PE  is  particularly  common  in  hospitalized  elderly  patients.PathophysiologyPE  is  usually  an  embolic  manifestation  of  deep  venous  thrombosis  (DVT),  which  is  caused  by  venous  stasis,  vein  wall  injury,  and  hypercoagulopathy.Other  etiologies  include  malignancy,  chronic  indwelling  central  venous  catheters,  pacemaker  leads,  and  spontaneous  thromboses.Emboli  become  lodged  in  the  pulmonary  artery  bed  and  lead  to  pulmonary  vascular  hypertension  by  several  proposed  processes:  redirected  pulmonary  blood  flow,  neurovascular  perturbation,  and  hormonal  changes.Clinical  featuresChronic  thromboembolic  pulmonary  hypertension  (CTEPH)  presents  insidiously  with  vague  symptomatology.  Suspicion  should  be  raised  when  signs  and  symptoms  for  DVT  (e.g.,  leg  swelling,  lower  extremity  venous  stasis  changes,  chest  pain,  hemoptysis)  are  encountered.The  most  common  symptoms  associated  with  pulmonary  hypertension  are  exertional  dyspnea,  presyncope/syncope,  and  nonspecific  chest  pain  or  pressure.The  physical  signs  of  CTEPH  are  related  to  right  heart  failure,  including  a  large  A  wave  progressing  to  a  predominant  V  wave  component  in  the  jugular  venous  pulse.  The  S2  sound  often  is  narrowly  split,  and  P2  is  accentuated;  a  sharp  systolic  ejection  click  may  be  heard  over  the  pulmonary  artery  in  the  second  intercostal  space.  Hypoxia/cyanosis  and  a  right  ventricular  heave  are  observed  with  advanced  disease.DiagnosticsCharacteristic  findings  on  plain  chest  radiography  are  central  pulmonary  vascular  enlargement,  vascular  pruning,  and  right  ventricular  enlargement.Electrocardiography  may  demonstrate  criteria  for  right  ventricular  hypertrophy,  including  right  axis  deviation  and  a  dominant  R  wave  in  V1.Pulmonary  function  tests  usually  reveal  minimal  changes  in  lung  volume  and  ventilation  with  normal  or  slightly  restricted  mechanics;  the  diffusing  capacity  of  the  lung  for  carbon  monoxide  (DLCO)  often  is  reduced  and  is  the  only  abnormality  on  this  test.The  ventilation  perfusion  lung  scan  is  essential  for  diagnosis;  an  entirely  normal  scan  excludes  the  diagnosis,  whereas  most  patients  with  CTEPH  demonstrate  one  or  more  segmental  or  larger  perfusion  defects  in  otherwise  normal  lung  regions.  The  magnitude  of  perfusion  defects  in  chronic  thromboembolic  disease  often  underestimates  the  actual  degree  of  vascular  obstruction.  A  positive  scan  should  prompt  a  right  heart  catheterization  and  pulmonary  angiography.High-resolution  computed  tomography  is  being  used  more  frequently  in  the  diagnosis  of  pulmonary  thromboembolic  disease.  However,  the  gold  standard  for  diagnosis  of  CTEPH  is  conventional  biplane  pulmonary  angiography.TreatmentMedical  therapy  for  CTEPH  is  limited  and  generally  palliative.  New  forms  of  drug  therapies  are  now  available  for  treatment  of  pulmonary  hypertension;  however,  their  benefit  in  patients  with  CTEPH  is  very  limited.  Chronic  anticoagulation  is  the  mainstay  of  medical  treatment  in  these  patients.Surgical  removal  of  chronic  thromboembolic  material  is  the  only  curative  option  for  patients  with  CTEPH.Outcomes  and  prognosisPulmonary  endarterectomy  (PEA)  is  a  proven  procedure  for  the  treatment  of  CTEPH  with  excellent  long-term  results.  A  30-year  experience  at  the  University  of  California,  San  Diego  (UCSD)  Medical  Center  indicated  an  overall  operative  mortality  of  8  percent.  This  has  declined  to  a  current  rate  of  about  2.2  percent.A  complication  specific  to  PEA  is  a  reperfusion  pulmonary  edema  that  appears  to  be  related  to  reperfusion  of  ...