Related Experiment Videos
[Pulmonary hypertension in autopsy cases of mixed connective tissue disease]
Abstract:
We histologically studied pulmonary vascular lesions of 11 MCTD autopsy cases without clinical manifestation of pulmonary hypertension (PH), and compared them with 6 advanced PH cases. Pulmonary vascular changes such as cellular intimal proliferation, intimal fibrosis, and fresh and/or organized thrombi characterized by PH were also found in non-PH cases. Furthermore, there was severe obstructive vasculopathy in small vessels of less than 100 microns in diameter, though they were not frequently observed in non-PH cases. These results suggest that morphological changes of pulmonary vessels in non-PH are qualitatively similar to those of PH. The important point between PH and non-PH cases in MCTD is whether the pulmonary arterioles over 200 microns in diameter are diffusely involved or not. The endothelial damage in the early stage, followed by microthrombi and proliferation of intimal myocytes seems to progress to severe pulmonary vascular diseases with PH.
Insights
Pulmonary vascular lesions in Mixed Connective Tissue Disease (MCTD) without pulmonary hypertension (PH) show similar changes to those with PH. The key difference lies in the diffuse involvement of larger pulmonary arterioles.
Area of Science:
- Cardiovascular Pathology
- Rheumatology
- Pulmonary Medicine
Context:
- Mixed Connective Tissue Disease (MCTD) can affect the pulmonary vasculature.
- Pulmonary hypertension (PH) is a severe complication of MCTD.
- Histological analysis is crucial for understanding vascular changes.
Purpose:
- To compare pulmonary vascular lesions in MCTD patients with and without clinical pulmonary hypertension (PH).
- To identify morphological differences and similarities in pulmonary vasculature between PH and non-PH MCTD cases.
- To elucidate the early pathological changes that may precede the development of PH in MCTD.
Summary:
- Pulmonary vascular lesions, including cellular intimal proliferation, fibrosis, and thrombi, were observed in MCTD autopsy cases without clinical PH, similar to those with advanced PH.
- Severe obstructive vasculopathy in small pulmonary vessels (<100 microns) was noted, though less frequent in non-PH cases.
- The diffuse involvement of pulmonary arterioles (>200 microns) distinguishes PH from non-PH MCTD cases, suggesting a progression from early endothelial damage and microthrombi.
Impact:
- Findings suggest that pulmonary vascular changes in MCTD are qualitatively similar regardless of clinical PH status.
- Early endothelial damage and microthrombi may represent a precursor stage to severe pulmonary vascular disease in MCTD.
- Histological assessment of pulmonary arteriole involvement is critical for evaluating PH risk in MCTD patients.