Background Pulmonary hypertension (PH) is defined as an increase in mean pulmonary arterial pressure (PAPm) greater than or equal to 25 mmHg at rest as assessed by right heart catheterization (RHC), but RHC is not routinely performed for the diagnosis of PH in a “real world” setting in Japan.
Objectives The aim of this study is to assess the change of frequency of RHC for the diagnosis of PH among patients with connective tissue diseases in our hospital, and to know if the decision to prescribe pulmonary hypertension drugs is affected by whether we perform RHC.
Methods Clinical records of admitted patients describe both the main diseases which were constantly followed by physicians and the actual diseases which were the reasons for admission. We analyzed the clinical records retrospectively of who was admitted to the wards of our rheumatology section for 10 years from Aug 1, 2005 to July 31, 2015. These 10 years were divided into two periods: the first half is from Aug 1, 2005 to July 31, 2010 (period A) and the latter half is from Aug 1, 2010 to July 31, 2015 (period B). We checked echocardiography, RHC and prescription for PH drugs. PH drugs include prostacyclin pathway agonists, endothelin receptor antagonists, and nitric oxide-cGMP enhancers.
Results We reviewed clinical records of 5,428 patients for ten years and we found 57 patients with the diagnosis of PH either in the section of main diseases or actual diseases. We used the label “tentative pulmonary hypertension (tentative PH)” for patients who showed peak tricuspid regurgitation gradient in thoracic echocardiography of more than or equal to 30 mmHg. Among the tentative PH patients, those whose PAPm were confirmed by RHC were labeled “true pulmonary hypertension (true PH)”. Forty patients among the 57 selected patients were categorized as having tentative PH and their original diseases were 20 with systemic sclerosis, 4 with Sjögren's syndrome, 3 with mixed connective tissue disease, and 2 with systemic lupus erythematosus, and so on. Among these 40 patients, 25 belonged to period A and 15 belonged to period B. RHC was performed for 9 patients (36.0%) in period A and true PH was diagnosed in 5 of those 9 patients (55.6%). Also RHC was performed for 12 patients (80.0%) in period B and 7 patients were found to have true PH (58.3%). In period A, 60% of true PH patients (3/5) and 60% of tentative PH patients (12/20) took PH drugs, and in period B, 71.4% of true PH patients (5/7) and 37.5% of tentative PH patients (3/8) took PH drugs.
Conclusions The frequency of RHC increased from 36% in the first half period to 80% in the latter half period in our hospital. In addition, the use of PH drugs did not depend on the confirmation of PH by RHC, particularly in the first half period. In Japan rheumatologists, including doctors at our hospital have a tendency to prescribe PH drugs without RHC data, but recently this tendency is changing. This tendency to not always perform RHC may be partly explained by the content of the guidelines from the Ministry of Health, Welfare and Labor in Japan.
Acknowledgement The authors thank Ms. Ayumi Kondou for her excellent secretarial assistance.
Disclosure of Interest None declared