Pulmonary arterial hypertension: use of delayed contrast-enhanced cardiovascular magnetic resonance in risk assessment.

Background: Pulmonary arterial hypertension is a severe and progressive disease. Its early diagnosis is the greatest clinical challenge.

Objective: To evaluate the presence and extension of the delayed myocardial contrast-enhanced cardiovascular magnetic resonance, as well as to verify if the percentage of the myocardial fibrosis mass is a severity predictor.

Methods: Cross-sectional study with 30 patients with pulmonary arterial hypertension of groups I and IV, subjected to clinical, functional and hemodynamic evaluation, and to cardiac magnetic resonance.

Results: The mean age of patients was 52 years old, with female predominance (77%). Among the patients, 53% had right ventricular failure at diagnosis, and 90% were in functional class II/III. The mean of the 6-minute walk test was 395 m. In hemodynamic study with right catheterism, the mean average pulmonary arterial pressure was 53.3 mmHg, of the cardiac index of 2.1 L/min.m(2), and median right atrial pressure was 13.5 mmHg. Delayed myocardial contrast-enhanced cardiovascular magnetic resonance was found in 28 patients. The mean fibrosis mass was 9.9 g and the median percentage of fibrosis mass was 6.17%. The presence of functional class IV, right ventricular failure at diagnosis, 6-minute walk test < 300 meters and right atrial pressure > 15 mmHg, with cardiac index < 2.0 L/min.m(2), there was a relevant association with the increased percentage of myocardial fibrosis.

Conclusion: The percentage of the myocardial fibrosis mass indicates a non-invasive marker with promising perspectives in identifying patients with high risk factors for pulmonary hypertension.