Pulmonary Embolism: Complications

The following are the most important diseases or complications that may be contributed to by pulmonary embolism:

Respiratory system (J0-J99)

Cardiovascular system (I00-I99)

  • Acute right ventricular failure (RHV) due to RV ischemia (reduced blood flow to the right ventricle (heart)).
  • Chronic cor pulmonale – right heart strain due to excessive pressure load.
  • Chronic thromboembolic pulmonary hypertension (CTEPH) due to recurrent pulmonary embolism (chronic thromboembolism):The 2-year prevalence for chronic thromboembolic pulmonary hypertension (CTEPH) is approximately 1-4%.Symptoms: Exertional dyspnea (shortness of breath on exertion), chest pain, fatigue, edema (water retention), or syncope (brief loss of consciousness); Diagnosis: echocardiography, followed by a ventilation perfusion scintigram; if necessary. also a right heart catheterization; therapy: surgical excision of the thrombotic material, i.e. pulmonary endarterectomy using the heart-lung machine; a new treatment option is pulmonary balloon angioplasty (pulmonary artery balloon angioplasty, BPA).
  • Pulmonary infarction – demarcation of a section of the lung no longer supplied with blood.
  • Recurrent pulmonary embolism
  • Atrial fibrillation (VHF) (approximately 10% of patients with pulmonary embolism presented with VHF; this had little or no effect on prognosis after acute pulmonary embolism)

Further

  • Acute phase: lethality (mortality related to the total number of people suffering from the disease) about 7-11 percent!
  • Pulmonary embolism mortality rate (number of deaths in a given period, relative to the number of the population in question) between the ages of 15 and 55 years:
    • Women: 13 per 1,000 deaths (because of sex difference: hormone- and pregnancy-associated thrombosis risk).
    • Men: 2-7 per 1,000 deaths.

Prognostic factors

  • Hypotension (low blood pressure) after acute pulmonary embolism leads to an increase in mortality (death rate) to more than 15%; patients with values ≤ 120 mmHg had a 20-fold increased likelihood of dying during hospitalization. According to one study, cut-off values of systolic 119.5 or diastolic 66.5 mmHg are predictors of hospital mortality. These thresholds more accurately predicted in-hospital mortality risk than did cardiac troponin I levels.
  • Right ventricular dysfunction: right ventricular dysfunction (RVD) is detected by a blood pressure index (BPI) ≤ 1.7 with a sensitivity of 92.8% (percentage of diseased patients in whom the disease is detected by use of the procedure, ie, a positive finding occurs) and a specificity (probability that actually healthy individuals who do not have the disease in question are also detected as healthy by the test) of 100%. Pulmonary embolism with right heart involvement is more likely to be fatal (9.5% of patients died, compared with 1.4% without RVD).

“Pulmonary Embolism Severity Index” (sPESI)

Predictors Points
Age > 80 years 1
Chronic heart failure (cardiac insufficiency) or pulmonary disease 1
History of cancer 1
Arterial oxygen saturation <90%. 1
Systolic blood pressure <100 mmHg 1
Heart rate ≥ 110 beats/min 1

Interpretation

  • 0 points: 30-day mortality studies is approximately 1% → patient can be discharged early within the next four days (or even within 24 hours) if he is hemodynamically stable and there are no reasons not to do so.
  • ≥ 1 points: Determination of right ventricular function by CT angiography (CTPE) or transthoracic echocardiography (TTE) and cardiac biomarkers (BNP, NT-proBNP, troponin I and T).
    • Right ventricular dysfunction + positive biomarker test → patient’s risk should be considered intermediate-high (otherwise intermediate-low) → systemic thrombolytic therapy (dissolution of a thrombus (blood clot) using drugs) should be considered.

Note: Pregnant women are not included in the sPESI; however, their premature discharge should be well considered!

Chronic thromboembolic pulmonary hypertension (CTEPH)

CTEPH score according to Klok et al.

Predictors (predictive factors) Points
Unprovoked pulmonary embolism +6
> 2 weeks delayed embolism diagnosis +3
Hypothyroidism (underactive thyroid gland) +3
Right ventricular dysfunction at diagnosis +2
Diabetes mellitus -3
Thrombolytic therapy (dissolution of a thrombus (blood clot) with the help of drugs) -3

Interpretation:

  • > 7 points: 10% risk of CTEPH.
  • 7 points (threshold): diagnostics required to exclude CTEPH.
  • <7 points: 0.38% risk of CTEPH.

Other predictors of CTEPH:

  • Previous thromboembolic disease
  • Large thrombus burden (CT-A) in acute LE
  • Right ventricular dysfunction on echocardiography in acute LE
  • Malignant and chronic inflammatory comorbidities.
  • Thrombophilia (tendency to thrombosis).
  • Clinical symptoms (dyspnea (shortness of breath); limited exercise tolerance).