Download Intraoperative Detection of Rate Dependent Left Bundle Branch Block

Soonchunhyang Medical Science 20(1):24-26, June 2014
pISSN: 2233-4289 I eISSN: 2233-4297
CASE REPORT
Intraoperative Detection of Rate Dependent Left Bundle Branch Block
Bon-Sung Koo, Mi-Soon Lee, Sung-Hwan Cho, Sang-Hyun Kim
Department of Anesthesiology and Pain Medicine, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of Medicine, Bucheon,
Korea
Rate dependent left bundle branch block (RDLBBB) is an uncommon case. RDLBBB is defined as an intraventricular conduction defect that may return, if only temporarily, to sinus rhythm at lower heart rates. It appears when the heart rate exceeds a certain critical value. Although RDLBBB is usually benign, its diagnosis and treatment have clinical importance for association of RDLBBB and
myocardial ischemia and infarction. Therefore, in the case of detection of intraoperative RDLBBB, a clear differentiation should be
done as soon as possible. Also it is important to start appropriate treatment and to do clinical follow-up examination. We report a
case of intraoperative RDLBBB during general anesthesia for laparoscopic cholecystectomy in 82 years old female patient who has
a history of hypertension.
Keywords: Bundle-branch block; Myocardial ischemia; Electrocardiography; General anesthesia
INTRODUCTION
roscopic cholecystectomy due to gallbladder stones. She had histories of cerebral infarction, Alzheimer’s disease, and hypertension.
Left bundle branch block (LBBB) is a common electrocardio-
She was being medicated with calcium channel blocker and beta
graphic abnormal finding in hypertensive patients. In a healthy
blocker for the treatment of hypertension for 10 years. Preopera-
young patient, LBBB may be benign. But in hypertensive or older
tive laboratory values were within normal limits. Preoperative
patients, it may be related to cardiovascular disease [1,2].
electrocardiogram (ECG) was normal sinus rhythm with heart
Rate dependent left bundle branch block (RDLBBB) is a rare ar-
rates at 60 beats per minute (bpm). Cardiac echocardiography re-
rhythmia during general anesthesia. RDLBBB is a transient bun-
vealed mild diastolic dysfunction with normal ventricular systolic
dle branch block that occurs when heart rate exceeds a certain
function and normal chamber sizes.
critical value. Although RDLBBB is usually benign, its diagnosis
Glycopyrrolate 0.2 mg was given intramuscularly 30 minutes
and treatment have clinical importance for association of RDLBBB
before arriving at operation theatre. On arrival in the operating
and myocardial ischemia and infarction [3]. Therefore, it is neces-
theatre, the patient was monitored using a three-lead ECG, pulse
sary to do careful observation and clear differentiation. We report
oximetry, non-invasive arterial pressure measurement (Solar
a case of intraoperative RDLBBB during general anesthesia for
8000; GE, Milwaukee, WI, USA), and a bispectral index monitor
laparoscopic cholecystectomy in 82 years old female patient who
(BIS, BIS XP; Aspect Medical Systems, Newton, MA, USA). Gen-
has a history of hypertension.
eral anesthesia was induced using infusion pump (Fresenius Kabi,
orchestra) with propofol (Marsh mode) and remifentanil (Minto
CASE REPORT
mode) at target effect site concentrations of 3.0 μg/mL and 3.0 ng/
mL, respectively. Trachea was intubated uneventfully after 2 min-
An 82 years old female patient was scheduled for elective lapa-
utes of bolus rocuronium bromide 0.6 mg/kg. After tracheal intu-
Correspondence to: Bon-Sung Koo
Department of Anesthesiology and Pain Medicine, Soonchunhyang University Bucheon Hospital, Soonchunhyang University College of
Medicine, 170 Jomaru-ro, Wonmi-gu, Bucheon 420-767, Korea
Tel: +82-32-621-5330, Fax: +82-32-621-5322, E-mail: [email protected]
Received: Oct. 24, 2013 / Accepted after revision: Apr. 9, 2014
24
http://jsms.sch.ac.kr
© 2014 Soonchunhyang Medical Research Institute
This is an Open Access article distributed under the terms of the
Creative Commons Attribution Non-Commercial License
(http://creativecommons.org/licenses/by-nc/3.0/).
Intraoperative Arrhythmia • Koo BS, et al.
bation, the heart rate increased to 80 bpm and a wide QRS com-
for additional testing, initially noninvasive such as echocardiogra-
plex with ST depression appeared at lead II on ECG. Blood pres-
phy, 24-hour ambulatory Holter monitoring, and exercise testing.
sure was within normal limits at this moment. Heart rate gradual-
In the selected case, invasive tests such as coronary angiography
ly decreased to 60 bpm after increasing plasma concentration of
and electrophysiologic study may be necessary to confirm or rule
remifentanil and propofol to 3.5 ng/mL and 3.5 μg/mL. Then ECG
out the suspicion of the heart disease [7].
was returned to normal sinus rhythm. As ECG abnormalities was
Rate dependent bundle branch block is defined as an intraven-
recovered suddenly without accompanying gradual changes in
tricular conduction defect that may return, if only temporarily, to
QRS width or ST segment, authors presumed that the ECG find-
sinus rhythm at lower heart rates [8]. The exact mechanism of
ing of this patient is relevant to that of RDLBBB.
such a block remains obscure but may result from anatomic and
During the operation, conversion between RDLBBB and NSR
pathologic interruptions in cardiac conducting bundle either due
was occurred 5 to 6 times as heart rate changes between early 60
to ventricular enlargement or strain from neurogenic or function-
bpm and over 70 bpm. Overall, the ECG finding was NSR when
al depression with or without underlying pathological lesions of
heart rates were within 60 bpm. Operation finished uneventfully.
the conducting tissue [9]. RDLBBB occurs when the heart rate ex-
RDLBBB reappeared at emergence phase and continued until the
ceeds a certain critical value [3]. The onset of RDLBBB is sudden
patient stayed at post-anesthesia care unit. Postoperative creatine
in most patients and once initiated, it persists until the heart rate is
kinase-MB, troponin-T values were within normal limits. On
slower than that which triggered it [3]. Bauer [9] reported that the
postoperative day 6, she was discharged from the hospital without
transition from normal to abnormal intraventricular conduction
any episodes.
may be related alterations of the rate by only 1 or 2 beats/min. This
critical heart rate is dependent on change in heart rate. With rapid
DISCUSSION
decrease in heart rate, sinus rhythm may appear at higher rates
and with rapid acceleration in heart rate, it may appear at lower
Recently, ECG is one of the most common diagnostic tools in
heart rates [8]. RDLBBB is usually found in patients with hyper-
routine clinical setting because of its wide diffusion, undemand-
tension or coronary artery disease, although up to ten percent may
ing feasibility, and low cost. As a result of a its broad use, the find-
have no evidence of organic heart disease [3,9]. In this case, the pa-
ing of LBBB in the absence of well-defined clinical setting has be-
tient also had a history of hypertension. And her preoperative
come relatively frequent and raises questions and often concerns
ECG finding was normal sinus rhythm with heart rates at 60 bpm.
[4].
Although RDLBBB is usually benign, its diagnosis and treatment
LBBB is a frequent electrocardiographic abnormality in hyper-
have clinical importance for several reasons. First, it may mask the
tensive patients. Also it may imply associated coronary artery dis-
electrocardiographic manifestations of other less benign distur-
ease, aortic valve disease or cardiomyopathies [5]. In a healthy
bances, such as myocardial ischemia and infarction. Second, the
young adult, isolated LBBB may be benign. But in hypertensive or
ST-T wave changes associated with LBBB may be mistaken for
older patients, it may signify a progressive degenerating myocardi-
ST-T changes due to ischemia. RDLBBB may also be mistaken for
um involving cardiac conduction system [1,2]. Incidence of LBBB
slow ventricular tachycardia and may be inappropriately treated
increases with age [5]. During last 30 years, the prevalence of LBBB
[3]. A clear differentiation of LBBB into a benign RDLBBB, and
in the general population has been reported to vary considerably
LBBB associated with myocardial ischemia or infarction, may
according to population size, sampling criteria, ranging 0.16% to
avoid the unnecessary postponement of a case because of high
0.82% [4]. The prognosis of LBBB has varied widely, mainly as a
cardiac risk [8].
result of the different population from which the cases were select-
Diagnostic methods should first be attempted by observation of
ed, presence or absence of heart disease, and the type and severity
changes in conduction with spontaneously occurring changes in
of heart disease [6]. Therefore, physicians should be aware of the
heart rate. If the diagnosis is not obvious and the bundle branch
role of LBBB and investigate the risk of cardiovascular events [4].
block persists, then judiciously changing the heart rate may prove
Corrado et al. [7] reported that patients who positive findings at
helpful [3]. Pharmacologic and physiologic manipulations which
basic clinical evaluation, as in the case of LBBB, should be referred
alter heart rate can be used to change conduction in patients with
Soonchunhyang Medical Science 20(1):24-26
http://jsms.sch.ac.kr
25
Koo BS, et al. • Intraoperative Arrhythmia
RDLBBB. Normal conduction is changed to LBBB in these pa-
REFERENCES
tients by increasing heart rate with exercise, valsalva, arterial cuff
release, amyl nitrate, or atropine [3]. Manipulations which slow
heart rate such as carotid massage, deep inspiration, and pharmacological agents like neostigmine, edrophonium or propranolol,
change the aberrant conduction back to normal with the slowing
of heart rate [10,11]. Manipulations which increase heart rate to induce a LBBB should be attempted with extreme caution by careful
titration of atropine only after myocardial ischemia has been ruled
out. Drug doses should be appropriately chosen to avoid inducing
tachyarrhythmias or precipitating myocardial ischemia [3]. These
provocative maneuvers should be used with caution in patients
with hypertension, angina, cerebrovascular or atrioventricular
node disease. Prevention of tachycardia and in some cases deliberately slowing the heart rate, can be of diagnostic and therapeutic
value [3].
In conclusion, rate dependent LBBB is an uncommon entity.
During anesthesia, RDLBBB may be related to hypertension or
tachycardia. And its appearance makes the diagnosis of acute
myocardial ischemia or infarction difficult. Therefore, in co-morbid patients with LBBB, it is always better to do further cardiac
evaluations in order to rule out an associated coronary artery disease. In the case of detection of intraoperative RDLBBB, a clear
differentiation should be done as soon as possible. Also it is important to start appropriate treatment and to do clinical follow-up ex-
1. Fahy GJ, Pinski SL, Miller DP, McCabe N, Pye C, Walsh MJ, et al. Natural
history of isolated bundle branch block. Am J Cardiol 1996;77:1185-90.
2.Grady TA, Chiu AC, Snader CE, Marwick TH, Thomas JD, Pashkow FJ,
et al. Prognostic significance of exercise-induced left bundle-branch
block. JAMA 1998;279:153-6.
3.Domino KB, LaMantia KL, Geer RT, Klineberg PL. Intraoperative diagnosis of rate-dependent bundle branch block. Can Anaesth Soc J 1984;
31(3 Pt 1):302-6.
4.Francia P, Balla C, Paneni F, Volpe M. Left bundle-branch block: pathophysiology, prognosis, and clinical management. Clin Cardiol 2007;
30:110-5.
5.Littmann L, Symanski JD. Hemodynamic implications of left bundle
branch block. J Electrocardiol 2000;33 Suppl:115-21.
6.Rabkin SW, Mathewson FA, Tate RB. Natural history of left bundlebranch block. Br Heart J 1980;43:164-9.
7.Corrado D, Pelliccia A, Bjornstad HH, Vanhees L, Biffi A, Borjesson M,
et al. Cardiovascular pre-participation screening of young competitive
athletes for prevention of sudden death: proposal for a common European protocol. Consensus Statement of the Study Group of Sport Cardiology of the Working Group of Cardiac Rehabilitation and Exercise Physiology and the Working Group of Myocardial and Pericardial Diseases of
the European Society of Cardiology. Eur Heart J 2005;26:516-24.
8. Mishra S, Nasa P, Goyal GN, Khurana H, Gupta D, Bhatnagar S. The rate
dependent bundle branch block: transition from left bundle branch block
to intraoperative normal sinus rhythm. Middle East J Anesthesiol 2009;
20:295-8.
9. Bauer GE. Transient bundle-branch block. Circulation 1964;29:730-8.
10.Bauer GE. Bundle-branch block under voluntary control. Br Heart J
1964;26:167-79.
11.Wallace AG, Laszlo J. Mechanisms influencing conduction in a case of
intermittent bundle branch block. Am Heart J 1961;61:548-55.
amination.
26
http://jsms.sch.ac.kr
Soonchunhyang Medical Science 20(1):24-26