Tanaka Hidekazu, Hiraishi Mana, Miyoshi Tatsuya, Tsuji Takayuki, Kaneko Akihiro, Ryo Keiko, Yamawaki Kohei, Fukuda Yuko, Norisada Kazuko, Tatsumi Kazuhiro, Matsumoto Kensuke, Kawai Hiroya, Hirata Ken-ichi
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
Cardiovasc Ultrasound. 2011 Feb 7;9(1):4. doi: 10.1186/1476-7120-9-4.
A 53-year-old man with depressed ejection fraction (EF) of 35% and QRS width of 88 ms at rest was admitted to our institution with a complaint of exertional chest discomfort and dyspnea. During treadmill exercise, left bundle-branch block (LBBB) with a QRS width of 152 ms occurred at a heart rate of 100 bpm. During LBBB, the patient showed significant mechanical dyssynchrony as evidenced by a two-dimensional speckle tracking radial strain of 260 ms (≥ 130 ms), defined as the time difference between anterior-septum and posterior wall. Five-month after carvedilol and candesartan administration, EF had improved to 49% and LBBB did not occur until a heart rate of 126 bpm was attained during treadmill exercise. It appears that pharmacological therapy may be useful for patients with heart failure and exercise-induced LBBB.
一名53岁男性，静息时射血分数（EF）为35%，QRS波宽度为88毫秒，因劳力性胸部不适和呼吸困难入院。在平板运动试验中，心率为100次/分时出现左束支传导阻滞（LBBB），QRS波宽度为152毫秒。在LBBB期间，患者表现出明显的机械性不同步，二维斑点追踪径向应变显示为260毫秒（≥130毫秒），定义为前间隔与后壁之间的时间差。服用卡维地洛和坎地沙坦五个月后，EF提高到49%，在平板运动试验中，直到心率达到126次/分时才出现LBBB。看来药物治疗可能对心力衰竭和运动诱发LBBB患者有用。
