Julius Stevo
University of Michigan Cardiovascular Center, Ann Arbor, MI, USA.
Prog Cardiovasc Dis. 2009 Jul-Aug;52(1):26-30. doi: 10.1016/j.pcad.2009.06.002.
Tachycardia is a strong predictor of both hypertension and excessive cardiovascular risk. This association is robust and prevails after multivariate adjustments for other cardiovascular risk factors. Despite the strong evidence, various guidelines do not list tachycardia as a risk factor because of unwarranted assumption that tachycardia is only a marker of patient's emotional state. Already in 1945, Levy et al showed that individuals with "transient tachycardia" at baseline developed 2-fold higher rates of "true" hypertension than the control group. In the general population of Tecumseh, Mich, tachycardia proved to be a permanently reproducible feature of prehypertension. In hypertension, fast heart rate is associated with high cardiac output, and this "hyperkinetic" hemodynamic picture is different from established hypertension. However, Lund Johansen has shown that after 20 years of observation, the cardiac output and stroke volume significantly decreased and a typical picture of high vascular resistance, treatment-requiring, established hypertension emerged. So far, only the 2007 European Society of Cardiology/European Society of Hypertension (ESC/ESH) guidelines acknowledged the validity of heart rate in evaluation of cardiovascular patients. The best way to convince the public is to demonstrate that lowering the heart rate with a drug without influence on blood pressure reduces cardiovascular events.
心动过速是高血压和心血管风险过高的有力预测指标。这种关联十分稳固,在对其他心血管危险因素进行多变量调整后依然存在。尽管有确凿证据,但各种指南并未将心动过速列为危险因素,原因是无端假定心动过速仅仅是患者情绪状态的一个指标。早在1945年,利维等人就表明,基线时出现“短暂性心动过速”的个体患“真性”高血压的几率比对照组高出两倍。在密歇根州蒂卡姆西的普通人群中,心动过速被证明是高血压前期一个可永久重现的特征。在高血压患者中,心率加快与心输出量增加有关,而这种“高动力型”血流动力学情况与确诊的高血压不同。然而,伦德·约翰森表明,经过20年的观察,心输出量和每搏输出量显著下降,出现了典型的高血管阻力、需要治疗的确诊高血压情况。到目前为止,只有2007年欧洲心脏病学会/欧洲高血压学会(ESC/ESH)指南认可心率在评估心血管疾病患者方面的有效性。说服公众的最佳方法是证明使用一种对血压无影响的药物降低心率可减少心血管事件。