Aljizeeri Ahmed, Gin Kenneth, Barnes Marion E, Lee Pui K, Nair Parvathy, Jue John, Tsang Teresa S M
Division of Cardiology, UBC, Vancouver General Hospital, Vancouver, British Columbia,, Canada.
Echocardiography. 2013 Jul;30(6):627-33. doi: 10.1111/echo.12119. Epub 2013 Jan 30.
Systemic hypertension is a major risk factor for heart disease and stroke. Data regarding temporal relationship of left atrial (LA) remodeling to onset of hypertension are sparse. We aimed to quantitate LA structural and functional remodeling in newly diagnosed hypertensive patients.
We prospectively identified 380 patients with newly diagnosed systemic hypertension naive to drug therapy, and 380 age-matched control subjects without any history or evidence of hypertension. History or evidence of prior cardiovascular events, congenital or valvular heart disease, and renal dysfunction were exclusion criteria. Prevalence of LA enlargement, LA mechanical dysfunction expressed in total emptying fraction, left ventricular (LV) diastolic dysfunction, LV hypertrophy, and their interrelationships were assessed.
Of the 380 newly diagnosed hypertensive patients, 285 (75%) had LA enlargement, 308 (81%) had LA mechanical dysfunction, and 19 (5%) had LVH. Diastolic dysfunction was present in 334 (88%) of the patients. Compared to the controls, the hypertensive group had larger maximal, minimal, and pre-A LA volumes (all P < 0.001). Total and active LA emptying fraction were significantly reduced (both P < 0.001). Total LA emptying fraction was strongly associated with systolic blood pressure [per 10 mmHg, HR 0.94 (0.89-0.98); P < 0.001], with stepwise decrease in LA emptying fraction of 6%, 10%, and 16% from the lowest (141-150 mmHg) to the top tertile of systolic blood pressure (>160 mmHg).
In this drug-naive cohort with newly diagnosed hypertension, LA structural and functional remodeling, and LV diastolic dysfunction were common findings prior to initiation of drug treatment. LVH was uncommon. Impairment of LA mechanical function was evident even in the mildly hypertensive subgroup.
系统性高血压是心脏病和中风的主要危险因素。关于左心房（LA）重塑与高血压发病时间关系的数据稀少。我们旨在对新诊断的高血压患者的LA结构和功能重塑进行定量分析。
我们前瞻性地确定了380例新诊断的未经药物治疗的系统性高血压患者，以及380例年龄匹配、无任何高血压病史或证据的对照受试者。排除标准为既往心血管事件、先天性或瓣膜性心脏病及肾功能不全的病史或证据。评估LA扩大的患病率、以总排空分数表示的LA机械功能障碍、左心室（LV）舒张功能障碍、LV肥厚及其相互关系。
在380例新诊断的高血压患者中，285例（75%）有LA扩大，308例（81%）有LA机械功能障碍，19例（5%）有LVH。334例（88%）患者存在舒张功能障碍。与对照组相比，高血压组的LA最大、最小和A波前容积更大（均P<0.001）。LA总排空分数和主动排空分数均显著降低（均P<0.001）。LA总排空分数与收缩压密切相关[每10 mmHg，HR 0.94（0.89 - 0.98）；P<0.001]，收缩压从最低三分位数（141 - 150 mmHg）到最高三分位数（>160 mmHg）时，LA排空分数逐步下降6%、10%和16%。
在这个新诊断的未接受药物治疗的高血压队列中，LA结构和功能重塑以及LV舒张功能障碍是药物治疗开始前的常见表现。LVH并不常见。即使在轻度高血压亚组中，LA机械功能受损也很明显。
