Prognosis of
Primary Pulmonary Hypertension (PPH)
The clinical course of PPH is generally one of
inexorable progression toward death. However, natural history studies vary in
reporting and in case ascertainment, and utilize different definitions of
survival duration (eg, the interval since onset of symptoms or the
interval since diagnosis), so that a consensus about the rate of progression of
the disease has been difficult to establish.
Among patients who do not undergo heart-lung
transplantation, actuarial survival at 1 year is 68 to 77 percent; 2 years, 52
to 58 percent; 3 years, 40 to 56 percent; 4 years, 30 to 43 percent; and 5
years, 22 to 38 percent. The usual mechanisms of death are right ventricular
failure (63 percent), pneumonia (7 percent), and sudden death (7 percent).
Primary Pulmonary Hypertension (PPH)
Survival Rates
Despite the overall dismal prognosis, duration of
survival ranges up to 10 years or more. Isolated instances of survival up to 24
years have been reported, as have rare cases of apparent regression
of the disease.
A variety of indicators appear to have predictive
value for short survival.
(1) Higher Pulmonary Vascular Resistance
and Pressure: Most studies have found an inverse correlation between
the pulmonary hemodynamic abnormality and survival. Among the 194
patients in the Patient Registry for the Characterization of Primary Pulmonary
Hypertension, median survival for those with a mean pulmonary arterial pressure
less than 55 mm Hg was 48 months, compared to 12 months for those with mean
pulmonary arterial pressure of 85 mm Hg or more.
The implications may be that in these patients,
the disease is more advanced or has progressed to a more severe level relatively
rapidly (ie, by the time of correct diagnosis). The higher pressure
imposes a greater workload on the right ventricle, contributing to death from
right-sided heart failure, the most common cause of mortality.
Some studies, however, have failed to identify
degree of pulmonary hypertension as a predictor of mortality, despite finding a
correlation with pulmonary resistance.
(2) Absence of Favorable Response to
Vasodilator Therapy: The response to vasodilator therapy has long been
recognized as being predictive of survival. There are two potential components
to this predictor. First, the ability of the pulmonary vasculature to respond to
vasodilator agents may identify patients in a more vasoreactive (earlier) phase
of the disease. Thus, those who demonstrate reduced pulmonary vascular
resistance with acute administration of vasodilators tend to survive longer, and
this may be independent of subsequent treatment status. Second, in
addition to the predictive role of vasodilators, there is suggestive evidence
that treatment with vasodilators may enhance survival. Preliminary
data from a 12-week randomized survival study of PPH patients treated with
prolonged intravenous prostacyclin also support this observation.
(3) Worse Functional Classification:
Most patients with PPH are symptomatic at the time of diagnosis. Nevertheless,
symptoms are presumably a late development in this disease, resulting mainly
from end-organ (right ventricular) sequelae. Level of symptomatic deterioration
may be considered a global clinical index of hemodynamic dysfunction. Among
symptomatic patients, those exhibiting more symptomatic decompensation have
shorter subsequent survival.In the registry, median survival for patients in New
York Heart Association class I or II was 58.6 months; class III, 31.5 months;
and in class IV, 6 months. (See
PPH Classifications)
(4) Right Atrial Pressure (RAP) Elevation:
Among measurable hemodynamic indices of right ventricular function, mean RAP
elevation is highly predictive of survival. Mean RAP greater than 20 mm Hg
corresponds to a median survival of 1 month, compared to 46 months survival for
patients with mean RAP less than 10 mm Hg.
(5) Depressed Cardiac Output:
Decreased cardiac output is associated with severity of PPH. It is caused by
both high fixed resistance to blood flow through the pulmonary vasculature and
right ventricular failure. Not unexpectedly, reduced cardiac output also
correlates with reduced survival. Cardiac index less than 2.0 L/min/m2
is associated with a median survival of 17 months; cardiac index of 4.0 L/min/m2
or more increases median survival to 43 months.
(6) Low Pulmonary Arterial (Mixed Venous)
Oxygen Desaturation: Low (less than 63 percent) 02
predicted a mean 3-year survival of 17 percent, whereas higher 02
predicted a mean survival of 55 percent at 3 years. The power of this factor
is
probably derived from its cumulative reflection of poor oxygenation due to
reduced capacity, arterial hypoxemia, and low cardiac output.
LEGAL OPTIONS FOR PPH PATIENTS
If
you or a loved one have been diagnosed with Primary Pulmonary Hypertension (PPH),
then you may have a right to file a individual legal action against the
manufacturers of the diet pills or others. Due to the nature of this serious and
devastating disease process, PPH patients are urged to contact an attorney
immediately after he or she has been informed of their Primary Pulmonary
Hypertension diagnosis. Many
important legal issues need to be addressed early after a PPH diagnosis, that
can affect the outcome of the PPH litigation. Call us for a Free Confidential
Consultation. Talk with a Board Certified Personal Injury Trial Lawyer about
your legal rights of a PPH claim against the diet drug industry and others. No
Fees or Expenses Charged unless we make a Recovery for You.
Call Us Toll Free at 1-800-883-9858
or 1-800-468-4878 or E-mail
us your questions on Free
Case Evaluation Form.
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