Successful treatment with landiolol for the recurrence of significant ST-segment depression during early postoperative period
Uwajima, Japan
* E-mail: ytakasak{at}uwajima-mh.go.jp
Editor—Tachycardia-induced ischaemia is more prevalent in patients with coronary artery disease during early postoperative period.1 As tachycardia increases the oxygen demand in myocardium with limited coronary blood flow, heart rate reduction is an essential treatment to attenuate myocardial ischaemia. Landiolol, an ultra-short-acting β-blocker, has been widely used to treat perioperative tachyarrhythmias in Japan. We report a case in which postoperative myocardial ischaemia denoted by significant ST-segment depression on electrocardiogram (ECG) monitoring was successfully treated with landiolol.
A 61-yr-old man (56 kg, 162 cm) underwent right carotid endarterectomy under general anaesthesia. Although the preoperative ECG at rest showed left ventricular hypertrophy due to his untreated hypertension, there was no indication of abnormal left ventricular wall motion on transthoracic echocardiography. After the proposed surgery was uneventfully completed in 230 min, he was transferred to the post-anaesthesia care unit without emergence. In the unit, mechanically ventilated support partially assisted his breathing with the trachea intubated under continuous sedation. On the second postoperative day, he was gradually weaned from the mechanical ventilation after stopping the sedation. During the weaning process, significant ST-segment depression in lead V5 was found once the heart rate exceeded 90 beats min–1, and the maximum value of ST-segment depression in lead V5 reached 0.33 mV. Bolus doses of i.v. landiolol 2.5 or 5 mg were given until the heart rate was <90 beats min–1. A total dose of 15 mg landiolol was given over approximately 5 min with recovery of the ST-segment depression without significant change in arterial pressure. As landiolol has a short duration of action, it was administered by continuous infusion at 5–10 µg kg–1 min–1 to prevent return of the tachycardia and ST-segment depression.
Although an amount of 15 mg of landiolol was necessary to achieve the target reduction in heart rate below the patient's ischaemic threshold, the arterial pressure remained almost unchanged, despite the potential for landiolol to impair the cardiac contraction by a negative inotropic action. Harasawa and colleagues2 reported that 0.1 or 0.2 mg kg–1 of bolus landiolol exerted an equipotent effect on heart rate reduction without affecting arterial pressure for the treatment of intraoperative tachycardia in surgical patients. Other clinical studies also demonstrated that 0.1–0.3 mg kg–1 of bolus landiolol effectively prevented tachycardia caused by tracheal intubation during anaesthesia induction.3–5 In our case, small doses of landiolol was titrated in this patient until the heart rate decreased below the ischaemic threshold, and a dose of 0.27 mg kg–1 was required over 5 min. Previous studies have excluded patients with coronary artery disease, but the pharmacological effect of landiolol observed in our patient including dose, onset time, and arterial pressure were consistent with those described previously.2–5 However, in the case of myocardial ischaemia associated with tachycardia, it may be safer to administer landiolol in a relatively small doses or continuously while monitoring the haemodynamic response than to give 0.2–0.3 mg kg–1 as a bolus infusion because of the possibility of further ischaemic myocardial dysfunction.
References
1 Landesberg G, Mosseri M, Zahger D, et al. Myocardial infarction after vascular surgery: the role of prolonged, stress-induced, ST depression-type ischemia. J Am Coll Cardiol (2001) 37::1839–45.
2 Harasawa R, Hayashi Y, Iwasaki M, Kamibayashi T, Mashimo T. Bolus administration of landiolol, a short-acting, selective β1-blocker, to treat tachycardia during anesthesia: a dose-dependent study. J Cardiothorac Vasc Anesth (2006) 20:793–5.[CrossRef][Web of Science][Medline]
3 Yamazaki A, Kinoshita H, Shimogai M, et al. Landiolol attenuates tachycardia in response to endotracheal intubation without affecting blood pressure. Can J Anaesth (2005) 52:254–7.[Web of Science][Medline]
4 Goyagi T, Tanaka M, Nishikawa T. Landiolol attenuates the cardiovascular response to tracheal intubation. J Anesth (2005) 19:282–6.[CrossRef][Web of Science][Medline]
5 Sugiura S, Seki S, Hidaka K, Masuoka M, Tsuchida H. The hemodynamic effects of landiolol, an ultra-short-acting β1-selective blocker, on endotracheal intubation in patients with and without hypertension. Anesth Analg (2007) 104:124–9.
CiteULike 
Connotea 
Del.icio.us What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||