Davila Carlos D, Forfia Paul R
Department of Medicine, Einstein Medical Center, Philadelphia, PA, USA.
Curr Treat Options Cardiovasc Med. 2015 Jun;17(6):382. doi: 10.1007/s11936-015-0382-1.
Pulmonary hypertension (PH) is simply defined as a mean pulmonary artery pressure greater than 25 mmHg at rest; however, may result from varying combinations of abnormal pulmonary artery (PA) blood flow, pulmonary vascular resistance (PVR), PA compliance, and pulmonary venous pressure. Mitral regurgitation (MR) allows for partial transmission of systemic arterial pressure into the pulmonary venous system. Mitral stenosis (MS) prevents pulmonary venous drainage into the left ventricle. In either case, the direct result is marked pressurization of the pulmonary venous system, with the primary cause of PH in significant mitral valve disease (PHMVD) being pulmonary venous hypertension (PVH). Chronic and severe PVH may then lead to muscularization of the pulmonary arterial bed, with a rise in PVR and loss of pulmonary arterial compliance that follows ("reactive" pulmonary vascular disease). Right heart dysfunction ensues once the PVR rises and the compliance falls to a point in which the right ventricle (RV) cannot overcome the increased afterload. However, it is worth emphasizing that in the setting of PHMVD, no matter the degree of mismatch between RV afterload and RV function, the root condition in the patient and cause of the PH remains severe MV disease. Without correction of the primary condition, the patient's heart failure (HF), PH, PVR, and RV dysfunction will remain or progress. Moreover, direct PH medical therapies are ineffective and may actually worsen left heart congestion in the setting of unremediated MVD. Therefore, although surgery may be a higher risk in some patients with PHMVD, the potential benefits justify the risks in the majority of cases. If needed, direct medical management of PH is far simpler and more effective once the MVD is corrected, given the degree of left heart congestion often improves dramatically. Therefore, corrective mitral valve intervention should be considered as the main and definitive treatment for these patients.
肺动脉高压（PH）的简单定义是静息时平均肺动脉压大于25 mmHg；然而，它可能由肺动脉（PA）血流异常、肺血管阻力（PVR）、PA顺应性和肺静脉压的不同组合引起。二尖瓣反流（MR）可使体循环动脉压部分传导至肺静脉系统。二尖瓣狭窄（MS）则阻止肺静脉血流入左心室。在这两种情况下，直接结果都是肺静脉系统显著增压，在重度二尖瓣疾病（PHMVD）中，PH的主要原因是肺静脉高压（PVH）。慢性重度PVH随后可能导致肺动脉床肌化，PVR升高，肺动脉顺应性丧失（“反应性”肺血管疾病）。一旦PVR升高且顺应性下降到右心室（RV）无法克服增加的后负荷的程度，就会出现右心功能障碍。然而，值得强调的是，在PHMVD的情况下，无论RV后负荷与RV功能之间的不匹配程度如何，患者的根本病情和PH的病因仍然是重度二尖瓣疾病。如果不纠正原发疾病，患者的心力衰竭（HF）、PH、PVR和RV功能障碍将持续存在或进展。此外，在未纠正的二尖瓣疾病情况下，直接的PH药物治疗无效，实际上可能会加重左心充血。因此，尽管手术对一些PHMVD患者可能风险更高，但在大多数情况下，潜在益处证明风险是合理的。如果需要，一旦二尖瓣疾病得到纠正，鉴于左心充血程度通常会显著改善，对PH的直接药物管理要简单得多且更有效。因此，应考虑对这些患者进行二尖瓣矫正干预作为主要的确定性治疗方法。
