It is often said that sickle cell disease does not kill. What kills a warrior are the complications from sickle cell. This series will focus on breaking down and understanding each of the complications that might develop from sickle cell, so that you can know how to prevent this, and how to catch it early.
Pulmonary hypertension (pHTN)—is a sustained elevation of blood pressure in the pulmonary arteries, defined as a pulmonary artery pressure over 30 mm Hg (millimeters of mercury) during exercise and more than 25 mm Hg at rest. The pulmonary arteries are the blood vessels that carry blood from your heart to your lungs. Between 20-30% of the people in America with sickle cell have pulmonary hypertension.
Risk factors: Among patients with SCD, risk factors for development of pHTN include increasing age, history of renal or cardiovascular impairment, high blood pressure, high lactate dehydrogenase (LDH) levels, elevated alkaline phosphatase level, decreased serum transferrin level, and if you have had your spleen taken out. In men with SCD, history of priapism (i.e., abnormally prolonged erection) is associated with increased risk of pHTN.
What causes Pulmonary Hypertension? There is no identified physiology that makes SCD patients more prone to pulmonary hypertension, but many factors have been suspected. The first is that we are in a chronic state of anemia, which means the heart has to pump more blood, since there is less hemoglobin carriers to pick up oxygen cells and distribute through the body. This increases the size of the heart muscle and blood vessels, thereby increasing the pressure. Another reason is that when cells lack oxygen, they die, and this starts the inflammatory process in the body where other cells rush in to fix the leak and stop further injury to the tissue. Constant cell death and inflammation stresses out the system, leaving you with damage to the blood vessels. The third process is due to iron overload. Since iron cannot be excreted, it just sits in your bloodstream, causing havoc and leading to more injury and cell death. The fourth option (and often most common) is that sickle cells clump up leading to clots that might block off smaller vessels, thereby putting more pressure on the larger pulmonary vessels since the circulation will bypass to them.
How do you know if you have pulmonary hypertension?
The chief symptom of pHTN is painful breathing, which is often attributed to anemia (or acute chest syndrome) . Other signs and symptoms may include chest pain, weakness, syncope, palpitations, fatigue, arms/legs swelling, distended abdomen, and huge, bulging veins on the side of your neck.
It is hard to diagnose Pulmonary Hypertension, especially in SCD patients because the symptoms often mirror acute chest syndrome. When you get your labs checked, have your doctor check your LDH or BNP
levels. If they are high, you could be at risk for pHTN. A doppler echocardiogram, pulmonary function test, or right heart catherization is used to confirm the diagnosis.
How do you treat it? Since Pulmonary Hypertension has no cure, the treatment is often just palliative or supportive. Unfortunately without proper management, patients with pHTN die within 2 years from diagnosis. Here are some treatment options that your doctor might recommend:
- Oxygen as needed especially when sleeping and during activities
- Frequently assess for signs and symptoms of potential complications, including pulmonary edema, cor pulmonale, and pulmonary embol
- Blood transfusions to increase the amount of hemoglobin in the body, thus reducing the pressure by the heart
- Antibiotics for infection (infections like bronchitis and pneumonia can be deadly with pHTN, since it puts more work on an overstressed pulmonary system
- Corticosteriods to help expand the blood vessels
- Pain meds
- Anticoagulants to decrease pulmonary vascular resistance, or other drugs like Epoposterol, Bosentan, or Sildenafil. All these drugs come with their own list of side effects.
- Monitor your blood pressure, if it’s too high, it increases the pulmonary hypertension
- Eat small, frequent meals to avoid gastrointestinal overload. When you eat large, heavy meals, this puts unnecessary strain on the abdominal aorta, which then puts pressure on the pulmonary artery.
- Got lots of rest. Even more than normal. When you are at rest, there is less pressure on your heart and lungs.
- Avoid stress, since stress invokes the fight-or-flight response which then puts your body into overdrive, increasing your pHTN.
Okay my warriors…those are the facts about pulmonary hypertension. I know a couple of warriors living with this condition, and it can be difficult to manage, but does not have to be the end of your story. To reduce your risk; manage hypertension, detoxify your kidneys, check your BNP/LDH levels because early treatment can slow the progression of the disease.
Knowledge is power. Be well.