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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 26, No 3, May/June 2015
114
AFRICA
Evaluation of left atrial mechanical function and atrial
conduction abnormalities in Maras powder (smokeless
tobacco) users and smokers
Ahmet Akcay, M Naci Aydin, Gurkan Acar, Bulent Mese, Mustafa Çetin, Mehmet Akgungor,
Eren Cabioglu, Orhan Bozoglan,
İ
dris Ardic, Musa Çakıcı
Abstract
Objective:
In Turkey, a type of smokeless tobacco called
Maras powder (MP) is widely used in the south-eastern
region. Smokeless tobacco is found in preparations for chew-
ing and for absorption by the nasal and oral mucosae. The
purpose of this study was to investigate whether MP damages
intra- and inter-atrial conduction delay and left atrial (LA)
mechanical function as much as cigarette smoking.
Method:
A total of 150 chronic MP users (50 males, 32.5
±
5.4 years), smokers (50 males, 32.1
±
6.0 years) and controls
(50 males, 30.1
±
5.8 years) were included in the study. LA
volumes were measured echocardiographically according to
the biplane area–length method. Atrial electromechanical
coupling was measured with tissue Doppler imaging and LA
mechanical function parameters were calculated.
Results:
The LA passive emptying fraction was significantly
decreased and LA active emptying volume (LAAEV) was
significantly increased in the MP group (
p
=
0.012 and
p
=
0.024, respectively), and the LA active emptying fraction
(LAAEF) was significantly increased in the smokers (
p
=
0.003). There was a positive correlation between the amount
of MP used and smoking (pack years) with LAAEV and
LAAEF (
r
=
0.26,
p
=
0.009 and
r
=
0.25,
p
=
0.013, respec-
tively). Lateral atrial electromechanical intervals (PA) were
significantly higher in MP users, and the septal mitral PA
was statistically higher in the smokers (
p
=
0.05 and
p
=
0.04,
respectively).
Conclusion:
We suggest that atrial electromechanical coupling
intervals were prolonged and LA mechanical function was
impaired in MP users and smokers, but there was no signifi-
cant difference between the MP users and smokers. These
findings may be markers of subclinical cardiac involvement
and tendency for atrial fibrillation.
Keywords:
smokeless tobacco, atrial electromechanical intervals,
left atrial function
Submitted 23/1/14, accepted 27/11/14
Cardiovasc J Afr
2015;
26
: 114–119
www.cvja.co.zaDOI: 10.5830/CVJA-2014-070
Tobacco use can be classified into smoking and smokeless
tobacco. Smokeless tobacco is chewed or is absorbed by the nasal
and oral mucosae. A type of smokeless tobacco called Maras
powder (MP) is used mostly in the south-eastern region of
Turkey, and in many cases users become addicted. It is obtained
from a tobacco plant species known as
Nicotiana rustica
Linn.
Nicotine concentrations in the tobacco used to produce MP are
eight to 10 times higher than those in tobacco used to produce
cigarettes.
1
MP and its negative effects on the cardiovascular
system have been well studied. MP is consumed in such a way
that increase in oxidative stress is inevitable and as a result it
accelerates the atherosclerotic process.
2,3
Cigarette smoke includes nicotine and toxic substances such
as carbon monoxide and polycyclic aromatic hydrocarbons.
4
Inhalation of these substances predisposes to several different
atherosclerotic syndromes,
5,6
and is also associated with the
occurrence of cardiac arrhythmia.
7,8
The pathophysiological mechanism of cigarette smoking-
induced cardiac arrhythmia is complicated, and the pro-fibrotic
effect of nicotine on myocardial tissue with its consequent
increased susceptibility to catecholamines, may play a role.
Moreover, other components of cigarette smoking, such as
carbon monoxide, as well as oxidative stress, are likely to
cause the generation of arrhythmias. It is also known that
cigarette smoking leads to cardiac autonomic dysfunction,
9
and it has been implicated in prolonged QT intervals in healthy
individuals.
10
However, the nicotine concentration in the blood
is more likely to cause the pro-arrhythmic effect of cigarette
smoking.
7,11
The risk of atrial and ventricular arrhythmia rises
due to increased nicotine levels.
9-12
The prolongation of intra- and inter-atrial electromechanical
intervals and the inhomogeneous propagation of sinus impulses
are well-known electrophysiological characteristics of atria
that are prone to fibrillation.
13
Left atrial (LA) volume and LA
Department of Cardiology, Faculty of Medicine,
Kahramanmaras Sutcuimam University, Kahramanmaras,
Turkey
Ahmet Akcay, MD
M Naci Aydin, MD
Gurkan Acar, MD
Mehmet Akgungor, MD
Eren Cabioglu, MD
İ
dris Ardic, MD
Department of Cardiovascular Surgery, Faculty of
Medicine, Kahramanmaras Sutcu Imam University,
Kahramanmaras, Turkey
Bulent Mese, MD
Orhan Bozoglan, MD
Department of Cardiology, Faculty of Medicine, Adıyaman
University, Adıyaman, Turkey
Mustafa Çetin, MD,
drmcetin@gmail.comMusa Çakıcı, MD