Background The cause of connective tissue diseases-associated pulmonary hypertension (CTD-PH) includes left heart disease and interstitial lung disease (ILD) as well as pulmonary arterial hypertension (PAH). Careful differential diagnosis of them will be required, because all of these treatment strategies are different (1,2). However, the possibility cannot be denied that left heart diseases are complicated in PAH in CTD patients and have some impact on their PAH.

Objectives To investigate whether left heart diseases can be complicated in CTD patients having PAH.

Methods A total of 396 CTD patients having either dyspnea or lower carbon monoxide diffusing capacity (DL_CO) was performed Doppler echocardiography before and after exercise with the Master's double two-step. Right heart catheterization (RHC) was recommended in 120 patients (30%) who had >45 mmHg of tricuspid regurgitation pressure gradient (TRPG) just after exercise Doppler echocardiography or who had unexplained dyspnea and <40% of DL_CO. Out of the 49 patients whose RHC data was available, 13 (27%) had ≥25 mmHg of mean pulmonary arterial pressure (mPAP) by RHC. Of them, 11 patients had less than 15 mmHg of pulmonary capillary wedge pressure (PCWP). We investigated whether left heart disease were seen in the 11 patients with PAH. Involvement of Left heart diseases was assessed using Doppler echocardiography, thallium scintigraphy, cardiac MRI, and biomarkers.

Results The 11 patients with PAH consisted of 8 with systemic sclerosis, each one with mixed connective tissue disease, systemic lupus erythematosus, and rheumatoid arthritis. Average age was 59.6. Average mPAP and PCWP was 30.7mmHg and 9.9 mmHg. Among 11 PAH patients, 6 (55%) showed <7 mmHg of diastolic pulmonary vascular pressure gradient (DPG). 5 patients (83%) out of them were suggested to have left heart diseases by increased left atrial volume index and E/E' on echocardiography (n=5, 83%) and/or delayed contrast enhancement on cardiac MRI (n=1,17%). Furthermore, 3 patients (60%) among 5 PAH patients who had ≥7 mmHg of DPG also showed some signs of left heart disease.

Conclusions Coexistence of left heart diseases such as diastolic dysfunction was seen in CTD-PAH patients, even among patients with higher DPG. Left heart diseases should be evaluated in CTD patients with PAH particularly who showed lower DPG values, because of the risk for the deterioration of left heart disease under the treatment with pulmonary vasodilators.

References

1. Wilson SR et el. Pulmonary hypertension and right ventricular dysfunction in left heart disease. Prog Cardiovasc Dis. 2012 Sep-Oct; 55(2): 104-18.

2. Le Pavec J et el. Systemic sclerosis-related pulmonary hypertension associated with interstitial lung disease. Arthritis Rheum, 2011 Aug; 63(8): 2456-64.

Disclosure of Interest None declared

DOI 10.1136/annrheumdis-2014-eular.4878