Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee.
Department of Medicine, Division of Cardiovascular Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
JAMA Cardiol. 2017 Dec 1;2(12):1361-1368. doi: 10.1001/jamacardio.2017.3882.
Pulmonary hypertension (PH) is diagnosed by a mean pulmonary arterial pressure (mPAP) value of at least 25 mm Hg during right heart catheterization (RHC). While several studies have demonstrated increased mortality in patients with mPAP less than that threshold, little is known about the natural history of borderline PH.
To test the hypothesis that patients with borderline PH have decreased survival compared with patients with lower mPAP and frequently develop overt PH and to identify clinical correlates of borderline PH.
DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study from 1998 to 2014 at Vanderbilt University Medical Center, comprising all patients undergoing routine RHC for clinical indication. We extracted demographics, clinical data, invasive hemodynamics, echocardiography, and vital status for all patients. Patients with mPAP values of 18 mm Hg or less, 19 to 24 mm Hg, and at least 25 mm Hg were classified as reference, borderline PH, and PH, respectively.
Mean pulmonary arterial pressure.
Our primary outcome was all-cause mortality after adjusting for clinically relevant covariates in a Cox proportional hazards model. Our secondary outcome was the diagnosis of overt PH in patients initially diagnosed with borderline PH. Both outcomes were determined prior to data analysis.
We identified 4343 patients (mean [SD] age, 59 [15] years, 51% women, and 86% white) among whom the prevalence of PH and borderline PH was 62% and 18%, respectively. Advanced age, features of the metabolic syndrome, and chronic heart and lung disease were independently associated with a higher likelihood of borderline PH compared with reference patients in a logistic regression model. After adjusting for 34 covariates in a Cox proportional hazards model, borderline PH was associated with increased mortality compared with reference patients (hazard ratio, 1.31; 95% CI, 1.04-1.65; P = .001). The hazard of death increased incrementally with higher mPAP, without an observed threshold. In the 70 patients with borderline PH who underwent a repeated RHC, 43 (61%) had developed overt PH, with a median increase in mPAP of 5 mm Hg (interquartile range, -1 to 11 mm Hg; P < .001).
Borderline PH is common in patients undergoing RHC and is associated with significant comorbidities, progression to overt PH, and decreased survival. Small increases in mPAP, even at values currently considered normal, are independently associated with increased mortality. Prospective studies are warranted to determine whether early intervention or closer monitoring improves clinical outcomes in these patients.
肺动脉高压（PH）通过右心导管检查（RHC）中至少 25mmHg 的平均肺动脉压（mPAP）值来诊断。尽管有几项研究表明，mPAP 值低于该阈值的患者死亡率增加，但对于边界 PH 的自然史知之甚少。
检验假设，即边界 PH 患者的生存率低于 mPAP 值较低的患者，并且经常发展为显性 PH，并确定边界 PH 的临床相关因素。
设计、设置和参与者：这是一项 1998 年至 2014 年在范德比尔特大学医学中心进行的回顾性队列研究，纳入了所有因临床指征接受常规 RHC 的患者。我们提取了所有患者的人口统计学、临床数据、有创血流动力学、超声心动图和生存状态。mPAP 值为 18mmHg 或更低、19 至 24mmHg 和至少 25mmHg 的患者分别被归类为参考值、边界 PH 和 PH。
平均肺动脉压。
我们的主要结果是在 Cox 比例风险模型中，在调整了临床相关协变量后，所有原因的死亡率。我们的次要结果是在最初诊断为边界 PH 的患者中诊断出显性 PH。这两个结果都是在数据分析之前确定的。
我们在 4343 名患者（平均[标准差]年龄为 59[15]岁，51%为女性，86%为白人）中发现了 PH 和边界 PH 的患病率分别为 62%和 18%。在 logistic 回归模型中，与参考患者相比，高龄、代谢综合征特征和慢性心脏和肺部疾病与更高的边界 PH 可能性独立相关。在 Cox 比例风险模型中调整了 34 个协变量后，与参考患者相比，边界 PH 与死亡率增加相关（风险比，1.31；95%CI，1.04-1.65；P=0.001）。随着 mPAP 的升高，死亡的风险逐渐增加，但没有观察到阈值。在接受重复 RHC 的 70 名边界 PH 患者中，有 43 名（61%）已发展为显性 PH，mPAP 中位数增加 5mmHg（四分位距，-1 至 11mmHg；P<0.001）。
边界 PH 在接受 RHC 的患者中很常见，与显著的合并症、进展为显性 PH 和生存率降低有关。即使在目前认为正常的 mPAP 值范围内，mPAP 的微小增加也与死亡率增加独立相关。需要前瞻性研究来确定早期干预或更密切的监测是否能改善这些患者的临床结局。
