text:
Page 1
n recent years increased interest has been
shown in the occurrence of atrial dysfunction
after cardioversion from atrial fibrillation.1,2
Atrial fibrillation is a common arrhythmia character-
ized by the loss of organized atrial contraction that
predisposes to thromboembolism.3,4 Postcardio-
version embolism may result from the dislodgment
of preexisting atrial thrombi after the return of atrial
contraction.4Recent studies have suggested an alter-
native explanation of the mechanism of thrombo-
embolism occurring after TEE-guided cardioversion.5
Fatkin and associates have shown that the mechani-
cal function of the atrial appendage is depressed
immediately after external electrical cardioversion.6
Received June 11, 1998, from the Department of Cardiology,
University of Modena and Reggio Emilia, Modena, Italy. Revised
manuscript accepted for publication December 19, 1998.
Address correspondence and reprint requests to Anna Vittoria
Mattioli, MD, Department of Cardiology, University of Modena and
Reggio Emilia, Policlinico via del pozzo, 71, 41100, Modena, Italy.
TEE, Transesophageal echocardiography; AEF, Atrial ejection
force; ECG, Electrocardiography; DC, Direct current; SD,
Standard deviation; CI, Confidence interval
1999 by the American Institute of Ultrasound in Medicine • J Ultrasound Med 18:289–294, 1999 • 0278-4297/ 99/ $3.50
Doppler Sonographic Evaluation
of Left Atrial Function After Cardioversion
of Atrial Fibrillation
Anna Vittoria Mattioli, MD, Annadele Castelli, MD, Sabina Sternieri, MD, Giorgio Mattioli, MD
Restoration of sinus rhythm is not always followed
by immediate return of effective atrial contraction.
Left atrial mechanical function can be assessed by
Doppler echocardiography; in the present study we
measured the atrial ejection force, which is a non-
invasive Doppler-derived parameter that measures
the strength of atrial contraction.The aim of the pre-
sent study was to evaluate the influence of clinical
and echocardiographic parameters: duration and
cause of atrial fibrillation, different modality of car-
dioversion, and left atrial size with respect to the
delay in the return of effective atrial contraction after
cardioversion. Seventy patients were randomly cho-
sen to undergo cardioversion by either direct current
shock or intravenously administered procainamide
hydrochloride. The 52 patients who had sinus
rhythm restored underwent a complete Doppler
echocardiographic examination 1 h after the restora-
tion of sinus rhythm and after 1 day, 7 days, and
1 month. The relation between clinical variables and
atrial ejection force was tested. Atrial ejection force
was greater immediately and 24 h after cardiover-
sion in patients who underwent pharmacologic ther-
apy compared to patients treated with direct current
shock (11.3 ± 3 versus 5 ± 2.9 dynes; P < 0.001). In
both groups atrial ejection force increased over time.
The mode of cardioversion was significantly associ-
ated with recovery of left atrial mechanical function
by day 1 in univariate and multivariate analysis
(odds ratio, 0.14; 95% confidence interval, 0.02–1.2).
The other variable associated with the delay in the
recovery of atrial function was a dilated left atrium
(odds ratio, 0.16; 95% confidence interval, 0.12–1.6).
Atrial ejection force is a noninvasive parameter that
can be easily measured after cardioversion and gives
accurate information about the recovery of left atrial
mechanical function. The recovery of left atrial func-
tion was influenced by the mode of cardioversion
and left atrial size. KEY WORDS: Atrial fibrillation;
Cardioversion; Atrial function.
Page 2
This finding suggests that the stunned left atrial
appendage may predispose the atria to thrombus
formation despite the restoration of sinus rhythm.7
The evaluation of atrial mechanical function may be
useful to identify patients who showed a delay in the
return of effective contractile function and determine
which clinical and echocardiographic parameters are
associated with the delay.8In the present study the
AEF, a noninvasive Doppler-derived parameter of
atrial function, was measured. The aim of the present
study was to evaluate the influence of different clin-
ical parameters on atrial function after electrical and
pharmacologic cardioversion.
Study Population
Hemodynamically stable adult patients referred for
cardioversion of atrial fibrillation were considered
for inclusion in the present study. Exclusion criteria
were atrial flutter, ejection fraction less than 35%, and
a recent episode of atrial fibrillation (less than 3
months). Of the 112 patients screened, 37 patients
returned to sinus rhythm before the treatment and
five patients had previous episodes of atrial flutter
and showed prevalent atrial flutter on ECG. The
remaining 70 patients were randomized to DC shock
or intravenously administered procainamide
hydrochloride. Our analysis excluded unsuccessful
cardioversions, and therefore 22 patients were
excluded from the study. The study was carried on
with the 52 patients undergoing successful car-
dioversion to sinus rhythm: 31 men and 21 women,
with a mean age of 62 ± 10 years.
Of the 35 patients who were treated with pro-
cainamide hydrochloride, 23 patients had sinus
rhythm restored (65.7%), and of the 35 patients who
underwent external electrical shock, 29 patients had
sinus rhythm restored (82.8%).
Underlying cardiovascular disease included coro-
nary artery disease (17 patients, 32.6%), hyperten-
sion (20 patients, 38.4%), and idiopathic or primary
atrial fibrillation (15 patients, 29%). The duration of
atrial fibrillation in the study group varied from 24 h
to 6 months. The majority of patients had the
arrhythmia lasting less than 2 weeks (79%).
Fasting patients underwent sedation with propofol
(1 to 3 mg/ kg of body weight). DC shock was per-
formed with the use of anterior paddles. Twenty-five
patients (86%) underwent cardioversion with a sin-
gle electrical shock; two shocks were required in the
other four patients. The mean amount of electrical
energy used for cardioversion was 256 ± 190 J per
Pharmacologic cardioversion was performed
using the following protocol: 100 mg of pro-
cainamide hydrochloride was intravenously admin-
istered every 5 min up to a maximum dose of 1 g.
Telemetry monitoring technicians notified the inves-
tigators as soon as normal sinus rhythm was restored
and they had obtained ECG rhythm strips. When the
first treatment was not successful, the patients
received an alternative drug and were excluded from
the echocardiographic study. All patients who
underwent cardioversion were treated with 250 mg
of slow release hydroquinidine two times/ day after
the restoration of sinus rhythm.
The initial echocardiographic study was performed
1 h after cardioversion. Two-dimensional imaging
was performed and a two-dimensional guided
Doppler transthoracic echocardiogram was obtained
with a commercial Hewlett-Packard (Louisville, KY)
echocardiograph with a 2.5 MHz probe. Left atrial
size was measured during telesystole along the
parasternal long axis view from two-dimensionally
guided M-mode tracings; the left atrial area was also
Transmitral pulsed Doppler energy was recorded
from the apical four-chamber view, with the sample
volume positioned between the tips of the mitral
leaflets. Mitral orifice area was assumed to be circu-
lar and estimated from the mitral annulus diameter
as measured from the apical four-chamber view.
The following echocardiographic parameters were
evaluated: left atrial dimension, left ventricular end
diastolic and end systolic dimension, mitral valve
diameter and area, ejection fraction.
Peak early filling (E) and atrial filling (A) velocities
were recorded. The velocity-time integral of the E
and A waves was obtained by integrating the flow
profile recorded in intervals of 4 ms. The percentage
by which atrial systole contributed to the filling of
the left ventricle was calculated by dividing the area
subtended by wave A by the total area subtended by
the diastolic velocity-time curve. The mean patient's
heart rate was less than 80 beats/ min, with a clear
separation between the E and A waves.
The AEF was evaluated by applying Newton's
second law of motion. According to Manning and
290ATRIAL FUNCTION AFTER CARDIOVERSIONJ Ultrasound Med 18:289–294, 1999
Page 3
colleagues,10the equation used for calculation was
AEF = 0.5 ×ρ×mitral orifice area ×(peak A velocity)2
where ρ is the density of blood (1.06 g/ cm3). The unit
force was measured in dynes.10In a previous study
the normal range of AEF in healthy subjects of dif-
ferent age decades was assessed.11All measurements
were taken during quiet breathing, with patients in
the left lateral decubitus position. The Doppler data
from three to five spectra were digitized and ana-
lyzed using an IBM computer.
Follow-Up Period
A complete Doppler echocardiographic examina-
tion was performed immediately after (1 h), and at
24 h, at 1 week, and at 1 month after the restoration
of sinus rhythm. The follow-up procedure was dis-
continued if atrial fibrillation returned. The protocol
was approved by the Ethical Committee of our uni-
versity, and all patients gave informed consent.
Statistical Analysis
Data are expressed as mean value ± 1 SD for con-
tinuous variables. The statistical significance of serial
changes in AEF, peak A velocity, and the integral of
the A wave after cardioversion was determined by
analysis of variance for repeated measures. Values
for patients of different groups were compared using
the Student unpaired t-test. Univariate and multi-
variate analyses were performed using Cox propor-
tional-hazards models. Odds ratio and 95% CIs were
calculated for categoric variables. A P value < 0.05
was considered significant.
Cardioversion from atrial fibrillation was obtained
with external DC shock in 29 patients (group I) and
pharmacologically in 23 patients (group II). No
patient showed clinical evidence of an immediate or
delayed thromboembolic event. Initial data for the
two groups of patients are shown in Table 1. The two
groups were similar with respect to age, duration of
atrial fibrillation, concomitant diseases, and left ven-
tricular function. The mitral valve area measured in
the two groups of patients was similar, and none had
mitral stenosis or relevant mitral regurgitation.
Identifiable atrial filling wave was observed in 50 of
the 52 patients by pulsed Doppler transmitral record-
ing performed within 1 h of cardioversion. The two
patients in whom it was not possible to record an A
wave underwent cardioversion using DC shock.
Using life table analysis, earlier recovery of effective
mechanical atrial function was observed in patients
who underwent cardioversion pharmacologically
compared with those who underwent DC shock (P <
0.01). The initial value of the AEF was significantly
lower in patients in group I than in patients in group
II (5 ± 2.9 versus 11.3 ± 3.0 dynes; P < 0.001) (Table 2).
Thirty-three (63%) of all patients recovered a normal
AEF by the first day. This group included 20 patients
(87%) from the procainamide hydrochloride group
and 13 patients (44.8%) from the DC shock group
(P < 0.01). The univariate analysis we used did not
uncover any significant association with age, dura-
tion, and cause of atrial fibrillation. The parameter
that was strongly related to AEF was the mode of car-
dioversion. Patients who underwent DC shock had
an odds ratio of 0.14 (95% CI, 0.02–1.2) to achieve a
normal AEF by day 1 (Fig. 1). By univariate analysis
left atrial size was the other parameter significantly
associated with the recovery of left atrial mechanical
function (odds ratio, 0.16; 95% CI, 0.12–1.6). The
mode of cardioversion was significantly associated
with normal AEF adjusted for age.
By day 7, 82.7% of patients recovered effective
atrial function and a normal AEF compared to nor-
mal values adjusted for age. They included 21
patients (91%) of the procainamide hydrochloride
group and 22 patients (75%) of the DC shock group.
291J Ultrasound Med 18:289–294, 1999 MATTIOLI ET AL
Table 1: Demographics, Atrial Fibrillation, and
Clinical Characteristics of Patients at Time of
Group I
(29 Patients) (23 Patients)
Group II
Age (years; mean ± SD)
Body mass index
61 ± 10
62 ± 11
Atrial fibrillation pattern:
Recent onset (<2 weeks) (%)
Chronic (>2 weeks) (%)
Prior episodes of atrial
23 (79)
6 (21)
17 (73)
6 (27)
1519 ns
Clinical characteristics:
Coronary artery disease (%)
Cardiomyopathy (%)
Hypertension (%)
No structural heart disease (%)
ns, Not significant.
Page 4
Over the 1 month follow-up period, reversion to
atrial fibrillation occurred in 10 patients: six patients
from group I and four patients from group II; P was
not significant. In patients in whom sinus rhythm
was maintained, however, AEF increased over the
observation period. The increase was more marked
in patients who had DC shock, and the difference
between the two groups of patients was no longer
statistically significant (Fig. 2).
The present randomized study evaluated the recov-
ery of atrial mechanical function after cardioversion
from atrial fibrillation. We have demonstrated that a
large number of patients recovered left atrial
mechanical function early after cardioversion. The
analysis at 1 h after cardioversion showed that 40%
of patients had recovered atrial function at that time.
After 24 h, about 60% of patients had recovered left
atrial mechanical function. Furthermore, 92% of
patients who underwent pharmacologic cardiover-
sion recovered atrial contraction by day 7. The mul-
tivariate analysis showed that the mode of
cardioversion influenced the recovery of atrial func-
tion. DC shock was associated with a higher proba-
bility of a depressed left atrial function compared to
pharmacologic cardioversion. The difference be-
tween the two groups of treatment was no longer sta-
tistically significant by day 7. This finding suggests
that left atrial stunning is an early phenomenon and
wears off between 1 and 7 days after cardioversion.
Evaluation of Atrial Function Using AEF
The AEF is a Doppler-derived parameter that was
first used by Manning and coworkers for the evalua-
tion of atrial mechanical function. They observed
that the strength of atrial contraction was reduced in
the early postcardioversion period and progressively
increased.10The AEF provides a physiologic assess-
ment of atrial systolic function because it includes
both the acceleration of blood ejected by the atrium
and the mass of blood ejected through the mitral
valve. The normal value of AEF varies by age accord-
ing to peak A wave velocity variation. Elderly
patients frequently had a secondary left ventricular
dysfunction that increased dependence on atrial sys-
tole to maintain an adequate ventricular filling.12To
avoid this bias the AEF in the present paper was
adjusted for patient age.11
Clinical and Echocardiographic Variables Influencing
Recovery of Atrial Mechanical Function
Recent reports tried to identify the role of different
clinical variables in the recovery of left atrial
mechanical function after cardioversion to sinus
rhythm. Manning and associates13reported that
early after cardioversion, the atrial function was bet-
ter in patients with atrial fibrillation lasting less than
2 weeks compared to patients with atrial fibrillation
lasting more than 6 weeks. In a previous paper we
found an earlier recovery of atrial function in
patients with atrial fibrillation alone compared to
patients with ischemic and hypertensive diseases.14
In the present evaluation the cause of atrial fibrilla-
tion did not influence atrial mechanical function.
Harjai and coworkers found that the only signifi-
cant parameter influencing atrial dysfunction was
the mode of cardioversion. Patients undergoing
292ATRIAL FUNCTION AFTER CARDIOVERSION J Ultrasound Med 18:289–294, 1999
Table 2: Echocardiographic Findings at the First
Control: Comparison Between the Two Groups
Group I
(29 Patients)
Group II
(23 Patients)P
Left atrium (mm)
LVEDD (mm)
LVESD (mm)
Ejection fraction (%)
Peak E wave (m/ s)
Peak A wave (m/ s)
AEF (dynes)
44.7 ± 2.9
53.1 ± 6
37.6 ± 4.2
65 ± 6
0.65 ± 9
0.30 ± 7
4.8 ± 2.6
40.2 ± 1.9
52 ± 3.4
36 ± 2.5
66 ± 5
0.60 ± 11
0.63 ± 5
13 ± 3
< 0.05
< 0.01
< 0.01
LVEDD, Left ventricular end diastolic diameter; LVESD, Left
ventricular end systolic diameter; ns, Not significant.
Figure 1 Transmitral inflow shows the two peaks after
cardioversion from atrial fibrillation on day 7. The peak A
velocity is normal for age.
Page 5
electrical cardioversion had a more pronounced
and prolonged depression of atrial function.2
Similarly, Manning and coworkers demonstrated
the temporal dependence of the return of atrial
mechanical activity associated with the mode of
cardioversion.15The major limitation of these previ-
ous studies was the nonrandomized design. In the
present study patients were randomized to phar-
macologic or electrical cardioversion to obtain two
similar groups. We reported a depressed atrial con-
traction in patients treated with DC shock com-
pared to patients treated with procainamide
hydrochloride. We suppose that the combination of
electrically and chemically induced myocardial
depression and the delay in the restoration of atrial
contraction may promote thrombosis. A potential
risk for thromboembolism exists for a period of
time after cardioversion.
The other parameter that was related to atrial
mechanical function was left atrial size. The
Framingham Study demonstrated that left atrial size
is significantly associated with the age-adjusted risk
for stroke in both sexes.16The mechanisms of
increased risk of stroke are incompletely known.
Left atrial dilation promotes stasis of blood, which
predisposes to thrombus formation. Recent reports
underline the association between left atrial dilation
and spontaneous echo-contrast and left atrial throm-
bosis evaluated by TEE.17,18The Stroke Prevention in
Atrial Fibrillation Study found an association
between stroke and left atrial enlargement,19while
two other cohort trials rejected such a relation.20,21In
the present study left atrial size was associated with
a recovery of atrial mechanical function. A persisting
enlarged left atrium may be associated with an
increased embolic risk. More accurate evaluation
will be needed to understand the role of left atrial
enlargement in the recovery of atrial function.
Risk of Thromboembolic Complications and
Clinical Implication of the Study
Embolic episodes can occur after cardioversion in
non-anticoagulated patients despite negative TEE
performed before cardioversion.22,23The mechanisms
could be related to blood stasis due to the delay in
the development of an effective atrial contraction.
Many data support the hypothesis that immediately
after cardioversion a thrombogenic period seems to
occur before atrial mechanical function has been
restored. This finding has important clinical implica-
tion on the duration of anticoagulant therapy after
cardioversion. Currently an anticoagulation period
of up to 4 weeks after cardioversion is strongly rec-
ommended.24The morbidity associated with antico-
agulant therapy is well known and could be reduced
if patients who do not need prolonged anticoagula-
tion could be identified. AEF can be helpful in iden-
tifying patients at high risk for thromboembolic
1.Silverman DI, Manning WJ: Role of echocardiography in
patients undergoing elective cardioversion of atrial fibril-
lation. Circulation 98:479, 1998
Harjai KJ, Mobarek SK, Cheirif J, et al: Clinical variables
affecting recovery of left atrial mechanical function after
cardioversion from atrial fibrillation. J Am Coll Cardiol
30:481, 1997
Kannel WB, Abbott RD, Savage DD, et al: Epidemiologic
features of chronic atrial fibrillation: The Framingham
Study. N Engl J Med 317:669, 1978
Goldman MJ: The management of chronic atrial fibrilla-
tion: Indications for and methods of conversion to sinus
rhythm. Prog Cardiovasc Dis 2:465, 1960
Black IW, Fatkin D, Sagar KB, et al: Exclusion of atrial
thrombus by transesophageal echocardiography does not
preclude embolism after cardioversion of atrial fibrilla-
tion: A Multicenter Study. Circulation 89:2509, 1994
Fatkin D, Kuchar DL, Thorburn CW, et al:
Transesophageal echocardiography before and during
direct current cardioversion of atrial fibrillation: Evidence
for "atrial stunning" as a mechanism of thromboembolic
complications. J Am Coll Cardiol 23:307, 1994
Grimm RA, Stewart WJ, Maloney JD: Impact of electrical
cardioversion for atrial fibrillation on left atrial
appendage function and spontaneous echo contrast:
Characterization by simultaneous transesophageal
echocardiography. J Am Coll Cardiol 22:1359, 1993
293J Ultrasound Med 18:289–294, 1999MATTIOLI ET AL
Figure 2 Serial evaluation of AEF. Comparison between the
two groups of patients during the follow-up period.


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Dr. Nicholas M. Grumbach, MD
Internal Medicine
- 400 Bald Hill Rd Ste 520
Warwick, RI 02886
- 2 Locations
- (401) 793-8520
Dr. Nicholas M. Grumbach graduated from the Mount Sinai School of Medicine in 1996. He works in Warwick, RI and 1 other location and specializes in Internal Medicine and Pediatrics. Dr. Grumbach is affiliated with Miriam Hospital, Newport Hospital and Rhode Island Hospital.
Internal Medicine, Pediatrics
Medical School: Mount Sinai School of Medicine; Graduated 1996
*This physician has multiple office locations. See Office Information for details.
2756 Post Rd Ste 103
Warwick, RI 02886
2783 W Shore Rd
Warwick, RI 02889
176 Toll Gate Rd Ste 203
Warwick, RI 02886
215 Toll Gate Rd Ste 209
Warwick, RI 02886
215 Toll Gate Rd Ste 209
Warwick, RI 02886


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This an illustration from a book i am working on called The Rocket to Planet Charlie. Everything is built in photoshop to create the very syrupy sort of realities. Hoping to have more images soon.
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