Marchetta Michele, Lopez Rocio I, Hogwood Austin C, Thomas Georgia, Abbate Gerardina, Markley Roshanak, Canada Justin M, Abbate Antonio
Berne Cardiovascular Research Center and Division of Cardiology, University of Virginia, Charlottesville, VA; and.
Pauley Heart Center and Department of Internal Medicine, Virginia Commonwealth University, Richmond, VA.
J Cardiovasc Pharmacol. 2025 Jun 19;86(1):28-32. doi: 10.1097/FJC.0000000000001705. eCollection 2025 Jul 1.
Postural orthostatic tachycardia syndrome (POTS) is a clinical syndrome of tachycardia on standing leading to palpitations, dizziness, chest pain, and/or fatigue. An exaggerated norepinephrine response with standing is often present in POTS, but it remains unclear whether the tachycardia is compensatory for a reduced stroke volume or whether the tachycardia is itself causing the symptoms of POTS. We herein report the effects of heart rate (HR) lowering with ivabradine, a selective I f channel blocker, on symptom burden in patients with POTS. After ivabradine treatment, there was a significant reduction in the change in HR with standing in all patients from 40 (30-70) to 15 (8-19) bpm ( P = 0.011), without significant changes in blood pressure. The Malmö score was significantly reduced in all patients from 86 (74-92) to 39 (32-66) ( P = 0.005). A correlation between change in HR with standing and the change in Malmö score (R = +0.828; R 2 quadratic = 0.635; P < 0.001) was present. The parallel improvement in HR response and symptoms with ivabradine suggests that the tachycardia response in POTS may not be considered compensatory but rather central to the pathophysiology of POTS symptoms.
体位性直立性心动过速综合征（POTS）是一种站立时心动过速的临床综合征，可导致心悸、头晕、胸痛和/或疲劳。POTS患者站立时通常会出现去甲肾上腺素反应过度，但目前尚不清楚心动过速是对每搏输出量减少的代偿，还是心动过速本身导致了POTS的症状。我们在此报告选择性I f通道阻滞剂伊伐布雷定降低心率（HR）对POTS患者症状负担的影响。伊伐布雷定治疗后，所有患者站立时HR的变化显著降低，从40（30 - 70）次/分钟降至15（8 - 19）次/分钟（P = 0.011），血压无显著变化。所有患者的马尔默评分从86（74 - 92）显著降至39（32 - 66）（P = 0.005）。站立时HR的变化与马尔默评分的变化之间存在相关性（R = +0.828；二次R² = 0.635；P < 0.001）。伊伐布雷定使HR反应和症状同时改善，这表明POTS中的心动过速反应可能不应被视为代偿性的，而可能是POTS症状病理生理学的核心。
