Document 6576790

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Document 6576790
Cardiac arrest and resuscitation / Wolff-Parkinson-White syndrome
| P 2 0 4 2 Concentrations of serum lnterteukin-8 after
successful cardiopulmonary resuscitation in
humans with cardiac arrest
P2044
379
Who survives non-shocked out of hospital
cardiopulmonary arrest
Arretttype
Intubated
%
Suntval to dtecharge(%)
Crew witnessed
(n-303)
Bystander
(n-3192)
Unwitnessed
<n-543)
Ye»
No
Yes
Mo
Yes
No
17
63
43
57
44
56
1Z0
55.6*
7.4
14.9*
1.7
4.3
"p < 0 001 intubatod versus non-lntubated
Murrjvariate regression analysis showed that both the number of shocks
delivered and intubation were adverse predictors of the outcome of resuscitation, although there was no statistical Interaction between the two. Patients
who arrested before the arrival of the ambulance and/or required multiple D.C.
shocks were more likely to be Intubated. The poor outcome in arrest requiring
paramedic skills Is likely to reflect the length and difficulty of the resuscitation
attempt However, only a randomised prospective trial could confirm its value
or otherwise in pre-hospltal resuscitation.
It has been observed that electrocardlographic preexcrtatlon changes over
time. However, few papers describe the natural course of Wolff-ParkinsonWhite (WPW) syndrome occurring on the routine etectrogram (ECG) in young
people.
Methods: To evaluate the natural course of WPW syndrome In young people,
We examined the record of annual medical examination and the annually
recorded routine ECG in 13459 (12898 male and 561 female) consecutive
healthy college students while they are enrolled in Nagasaki Institute of Applied
Science between 1965 and 1995.
Results: 32 subjects were found to have preexcftation at enrollment, for a
prevalence ol 2.4 per 1000. An additional 2 subjects were found to have a delta
wave during follow up. Total 34 study subjects (0.25%) (33 male, 1 female)
were found to have WPW syndrome In the 4-year follow up. The mean age at
entry was 18.4 years (range, 18 to 21 years). 8 subjects (24%) had palpitations.
Of these, 3 subjects had clinical evidence of paroxysmal supraventricular
tachycardia. However, these subjects did not need to be treated for symptoms
of their arrhythmias. 5 of 34 study subjects (15%) had intermittent WPW
syndrome: 4 of 5 wtth Intermittent preexcftation at enrollment 3 of 32 study
subjects (9%) whofirstdemonstrated preexdtatJon did not have a delta wave
by the end of follow up. All subjects remained alive during study. The location
of accessory pathways determined by surface ECG was left lateral 15, left
posterior 4, posteroseptal 5, right free wall 9, anteroseptal 1.
In conclusion, 4-year follow up of college students with WPW syndrome
revealed that delta wave has disappeared, WPW syndrome did not confer
excess mortality, even in the subject who developed symptomatic arrhythmias
and there were many left sided accessory pathways.
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AJ. Mortey-Davies, J. Sirel, S.M. Cobbe. Dept. of Medical Cardiology,
K.G. Shyu, H. Chang, C.C. Un, C.S. Un, P.L Kuan, C.R. Hung. Departments
Glasgow Royal Infirmary, Glasgow, UK
of Internal Medicine, Emergency Medicine and Surgery, ShtnKong Wu Ho-Su
Cardiopulmonary arrest Is the leading cause of death in the UK. Patients preMemorial Hospital, Taipei, Taiwan
senting in rhythms other than ventricular tachyarrhythmias i.e. non-shocked
arrests (NSA). have a dismal outlook but there is limited data on their contribulnterteukin-8 (IL-8) is produced by various types ol human cells. It was the
tion to total survival.
mediator of reperfusion injury in animal models. In humans, the elect of
cardiac arrest (CA) and successful CPR on serum IL-8 levels is not known. In
Methods: From 1988 all out of hospital cardtopulmonary resuscitation (CPR)
attempts in Scotland have been registered on the Heartstart Scotland 2000
order to measure serum IL-8 after CPR and compare changes of IL-8 levels
database. NSA were defined as ambulance calls requiring either bystander or
with hemodynamic variables after CPR, we conducted a prospective study in
crew CPR where no shockable rhythm wasrecordedby the deflbrillator. Results
patients with normothermlc, non-traumatic CA.
are presented In the Utsteln Style. Response time is defined as emergency caB
Methods: 39 patients (pts) with out-of-hospltal CA undergoing CPR were
to arrival at the scene.
enrolled. Venous blood samples were taken after CPR and at 1, and 2 hours
after restoration of spontaneous circulation (ROSC) in order to measure serum
Results: 9161 arrests had complete outcome data, 4906 were shocked and
IL-8 by EUSA method. Heart rate and blood pressure were measured at the
4255 non-shocked. Survival was significantly greater in shocked arrests (13%
Vs 1%, p < 0.001 CW Square). There were 44 NSA survivors, accounting
same time when blood samples were taken.
for over 6% of all survivors In this data series. 4 arrests were excluded from
Results: In 19 pts, ROSC was achieved; In the remaining 20 pts successful
analysis as the victims were fully conscious on crew arrival and they may not
CPR was not possible. Mean serum IL-8 levels after CPR were significantly
represent "true" cardiopulmonary arrest.
higher in resuscitated pts than In nonresuscitated pts (228 ± 85 vs 5.9 ± 2.2
pg/ml, p < 0.01). The IL-8 levels in nonresuscitated pts were not significantly
Non-shocked
Witness
dlf erent from those of normal healthy control. At 1 and 2 hours after ROSC, the
Unwitnessed
Bystander
C/ew
mean serum IL-8 levels were 282 ± 8 2 and 416 ±143 pg/ml, respectively. Mean
values of systolic Wood pressure Immediately after, 1 and 2 hours after ROSC
1534
Total
2387
279
CPR pre ambulance
CPF1+
CPRCPR+ C P f l were 117 ± 9, 130 ± 11, and 136 ± 13 mmHg, respectively. No significant
525
1009
992
279
1395
correlations were found between hemodynamic values and serum IL-8 levels.
67%
42%
CPR%
33%
58%
The levels of IL-8 were not significantly different between those pts who could
37
Admitted to ward
25
55
78
30
be discharged from the hospital and those pts who could not
Admitted %
3.8%
5.7%
4.8%
5.5%
11%
In conclusion, successful Initial CPR was associated with increased serum
1
Discharged alive
6
17
10
10
IL-8 concentrations in pts with CA. The serum IL-8 levels remained at high
0.6%
1.2%
0.2%
Otscharged%
1.0%
36%
values at 2 hours after ROSC.
There were no significant differences in age, response time, or frequency
of pre-ambulance CPR between survivors and non-survivors of NSA (MannWhitney p > 0.1). More NSA survivors had witnessed arrests. Arrest cause: 16
Out of hospital cardiac arrest and advanced life
were cardiac, 12respiratory,6 secondary to drug overdose, 2 to trauma and
support skills: the Heartstart Scotland project
one each to pulmonary embolus, cerebrovascular accident and "cot death".
J.N. Adams, S.M. Cobbe, J. Sirel, A.K. Marsden'. Department Medical
The cause was unknown in 5 cases.
1
Cardiology, Royal Infirmary; Scottish Ambulance Service, Glasgow, UK
Conclusion: Patients with out of hospital cardiopulmonary arrest presenting
in non-shockable rhythms represent a heterogeneous group. Despite the low
Increasing numbers of paramedic ambulance personnel are trained In advanced
survival rate they constitute a significant proportion of all survivors.
life support techniques including endotracheal intubation. However the value
of these skills used in the management of pre-hospftal arrest has never been
confirmed in a randomised clinical trial and it has been suggested that the
use of full paramedic skills results in a poorer outcome than defibrillation
alone. We reviewed data from all pre-hospital cardiac arrest between 1991
WOLFF-PARKINSON-WHITE SYNDROME
and 1994. In 3872 (45.5%) case paramedic skills were used and of these 217
(5.6%) survived to discharge compared with a survival rale of 7.9% when these
P2045 Follow up study of 4 years In college students with
skills were not utilised. Data on the 4038 patients who received one or more
Wolff-Parklnson-Whhe syndrome
D.C. shocks were reviewed separately; patients were categorised according to
whether the arrest occurred after arrival of the ambulance (crew witnessed),
M. Hayano', S. Ozaki 2 , C. Ueyama', T. Hlrata', R. Sakamoto1, N. Komiya',
or before arrival (bystander witnessed or unwitnessed). The outcome in these
M. Nonaka'.S. Nakao1, K. Tsukahara1, K. Yano1. The 3rd Department of
patients Is indicated In the table below.
Internal Medicine, School ot Medicine, Nagasaki University;2 Health Center,
Nagasaki Institute of Applied Science, Nagasaki, Japan
380
Wolff-Parkinson-White syndrome
P 2 0 4 6 Ventricular fibrillation In Wolff-Parklnson-Whlte
syndrome: lesson from a population
non-pharmacologically treated
J A Salerno, R. Do Ponti, C. Storti, M. Zarcflni, A. Ferrari, M. VTgano1. Dlv. of
CarrOol.;1 Dtv. of CarxSosurg., IRCCS Pol. S. Matteo, Univ. of Pavia, Italy
P2047
Incidence of documented atrial fibrillation after
successful catheter ablation of the
Wolff-Parklnson-Whlte syndrome
Hjortur Oddsson', Nils Edvardsson, Hakan Walfridsson. 1 DMston of
Cardiology, Orebro; Sahlgrens' University Hospital, Gdteborg, Sweden
Background: Radiofrequency catheter ablation (RF) is an effective treatment
of reentrant tachycardias but It is less -well known to what extent recurrence of
atrial fibrillation (AF) is prevented by successful RF.
Material: 183 consecutive patients (pts) with Woll-ParWnson-Wrifte syndrome (WPW) underwent successful RF. Mean age 37.2 ± 16.5 year (range
10-79 year). 141 pts had overt WPW w h i l e ^ e f t s had concealed WPW. 53 of
183 pts (29%) had AF prior to RF, 7 eeneealee'-ane' 46 overt WPW. Evaluation
of recurrent arrhythmias was done using a questionnafre, hospital records and
individual contacts. The follow-up period was 21.8 ± 11.5 months.
Results: The 53 pts who had AF before RF were characterised by higher
age (45 ± 15.2 vs 33 ± 15.9 p = 0.0001), increased atrial vulnerability (42
vs 18% p - 0.001) (induced AF during Incremental atrial pacing or single or
double extrastimuD), male gender (75 vs 52% p - 0.004), and preexcitation (87
vs 73% p - 0.05), while no correlation was found between the location of the
accessory pathways, structural heart disease or the duration of symptoms.
AF occurred In 11 ef 183 pts after successful RF (6%). All eleven pts had
AF prior to RF. The following factors predicted recurrence of AF; previous AF
(100 vs 24% p - 0.0001), higher age (56 ± 11.8 vs 36 ± 16.1 year p - 0.0004),
longer duration of symptoms (24 ± 16.3 vs 15 ± 12.7 year p - 0.03), and
Increased atrial vulnerability (82 vs 22% p = 0.0001).
Conclusions: The reduction in incidence of AF after successful RF indicates
that the accessory pathway often Is Involved In the occurrence of AF but is not
the only etiotogfcal factor. Previous AF, high age and atrial vulnerability appears
to predict reoccurrence of atrial fforillation after successful RF.
R. Hatala', W. Supper, W. Kaltenbrunner, F. Freihoff, K. Stelnbach.
L-Boltzmarm Arrhythmia Research InsL, Withelminenhospital, Vienna,
Austria:1 Cardiovascular Dis. InsL, Bratislava, Slovakia
Though atrial fibrBlation (A-FIb) is common In patients (pts) with WPW syndrome, relatively BttJe Is known about its recurrence (REC) following a successful
(8ucc) raofofrequency catheter ablation (RFCA) of accessory pathway (AP).
Therefore, It was the aim of this study to determine the value of post-RFCA
follow-up (F-U) etectrophystotogic study (EPS) in predicting spontaneous A-Fft>
REC after succ RFCA. Induced A-Ftt) was considered clinically relevant only if:
1. it was indudbte under basal condrttons (no teoproterenol) 2. it persisted for
> 1 hour ("sustained" A-Fto) and required acute antiarrhythmic medication. For
this purpose, 152 WPW pts free of structural heart disease undergoing succ
RFCA of AP were prospectjvety evaluated. All pts underwent a F-U EPS (basal
conditions and isoproterenol infusion) 32 ± 14 days post succ RFCA. The atrial
stimulation protocol comprised programmed stimulation on 2 basic drives with
up to 2 extrastimuli and rapid pacing with decremental cycle lengths until 1:1
AV nodal conduction was tost All pts were clinically followed for a mean period
of 16 ± 9 months.
Results: A-Fib was clinically documented prior to RFCA in 46/152 pts (30%).
During F-U EPS, sustained A-FIb was induced in 8 pts: 7 had A-Rb documented
prior to RFCA, 1 pt had not Thus, A-Flb was Inducible on F-U EPS In 7/46 pts
with pre-RFCA A-Fib occurrence and In 1/106 pts without It (p < 0.001). Succ
RFCA of AP has eliminated In long term the REC of A-Rb In 38/46 pts (83%).
A-Flb spontaneously recurred post-succ RFCA In 8 pts, 5 of them had A-Flb
inducWe during F-U EPS. The specificity and sensitivity of A-Fto induced during
F-U EPS for the later spontaneous A-Fib REC is 98% and 63%, respectively.
CondusJons: Pts with sustained A-Rb inducible during F-U EPS post-RFCA
are prone to spontaneous clinically relevant A-Fib REC during subsequent F-U.
Thus, F-U EPS helps to identify pts who are at risk of A-Rb REC despite
successful RFCA of AP.
P2049 Comparative Inducibility and subsequent duration of
atrial fibrillation In asymptomatic
Wofff-Parklnson-Whrte syndrome patients and In
normal subjects
D.-D. lonescu, A. Antonovtci, M. Enache, E. Danalla. Cardiology Department,
Central Military Hospital, Bucharest, Romania
Stressful activities may induee atrial fibrillation (AF) In Wolff-Parklnson-Whlte
(WPW) Individuals who had no-previous symptoms.
To address the issue we studied the comparative indudbiDty and subsequent
duration of AF in 23 asymptomatic otherwise healthy youngsters with overt
WPW syndrome aged 19-22 taken as patients (P) and in 10 normals (N) of the
same age. The ATlrtdDCtionTJfotocol conststed In high-frequency (toea/min.)
pacing of the right atrium (RA) in 6 successive attempts of 1, 5, 10, 20, 30
and 60 sec duration until either AF Induction or completion of protocol. The
serial number of the successful attempt was considered as an inverse index of
Inducibility (I,). AF was induced In all P (I) = 1 In 3, li - 2 In 8, \ - 3 In 7,1, - 4 In
2, I | - 5 l n 1 a n d l | = 6in2)butin only 7 N (li - 3 in 1, \ - 4 in 1, l| - 5 In 3 and l| in
2) the rest of 3 N being computed with l| = 7 as nonindudble. Statistical analysis
of I) (Mann-WNtney-Wilcoxon test) revealed significant differences between P
and N (p - 0.00027).
AF duration (AFD) determined on a filtered bieolar RA electrograrn was less
than 5 sec in 2 N, 5-60 sec in 4 N and 3 P, 1-5 mln in 1 N and 5 P and more
than 5 min In 15 P. For measurement of the shortest preexcited RR interval
(SRR-PX) in 8 P we performed more inducing attempts until an AF lasting more
than 5 min was obtained (not counted as AFD). In 3 P AFD was more than 30
mln (47 min, 1 h 22 min, and 5 h) and in 1 P cardioversfon had to be performed
after 10 min because of high ventricular rate and hypotension. The AFD was
also significantly dif erent between P and N (Mann-Whitney-Wilcoxon test; p =
0.00053). In P, the SRR-PX correlated well with I, (r - 0.82, p < 0.0001) but not
with AFD (r - 0.3433, p = 0.1176).
Conclusion: In asymptomatic WPW P with no other pathologic finding AF is
much more easily indudble and lasts longer than In healthy subjects of the
same age. The presence of accessory pathways and the shortness of their
artegrade refractory period appear to be risk factors for AF.
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Ventricular fibrillation (VF) in pts with Wotfl-Parkinson-White syndrome (WPW)
can be a rare but potentially fatal event; in a selected population referred for
non pharmacological treatment its incidence may be not irrelevant The aim of
this study Is to report the characteristics of WPW pts who had previously experienced documented VF. Among the 715 WPW pts referred tor surgical ablation
(185 pts) or racflofrequency catheter ablation (530 pts), 21 pts (15M, 6F; age 30
± 12 yrs, range 18-57) with manifest accessory pathway experienced at least
1 episode of VF; pts with associated heart disease were excluded. In 9/21 pts
(43%), VF was present at hospital admission, in another 9/21 pts (43%) atrial
ftorillatlon (AF) degenerated Into VF during in-hospital Intravenous administration of antiarrhythmic drugs; in the remalng 3/21 pts (14%) the degeneration
into VF was observed only during AF Induced at electrophyslologlcal study
(EPS). Seven/21 pts (33%) had history of palpitation, another 6/21 pts (29%)
of non documented syncopal episodes; the remaining 8/21 pts (38%) were
completely asymptomatic. At EPS, the shortest R-R interval during induced AF
was 180 ± 21 ms with 90-100% of preexcftated beats. The accessory pathway
localization was as follows: free wall In 10/21 (48%) pts (left-sided in 9 and
right-sided In 1), septal in 1/21 (4%) pts, postero-medal In 10/21 (48%) pts
(left-sided In 5 and right-sided In 5). The accessory pathway was Interrupted
by surgical cryoablation in the first 9 pts and by RFCA In the last 12.
In conclusion: in a selected population of WPW pts, the occurrence of VF
accounts for 3% and Is unrelated to organic heart disease. A considerable
group of pts was asymptomatic before the potentially fatal episode of VF. Intravenous administration of antiarrhythmic drugs during preexcited AF, although
of common practice in Italian emergency rooms, might possajly contribute to
degeneration into VF. In this population, the prevalence of postero-medial accessory pathway location seems to be higher than in the general population of
WPW pts.
P2048 Inducibillty of atrial fibrillation during follow-up
electrophysiotoojc study predicts Its spontaneous
recurrence after successful catheter ablation of
accessory pathways
Wolff-Parkinson- White syndrome I Heart rate variability
P2050
Value of several electrocardiographs algorithms to
localize the ventricular Insertion of accessory
pathways In Wotff-Parkinson-White syndrome
J. Farre, J.A. Cabrera, J.M. Rubto, F. Navauo, L Sanziard, I. Lopez-Bravo,
E. Aguado, R. Buj, P.P. Perez, M. Zamora. Arrhythmia Unit, Fundaddn
Jimtnez Diaz, Madrid, Spain
Several ECG algorithms (ALG) have been proposed to localize the accessory
pathway (AP) in WPW patients (Pts). In 50 consecutive WPW Pts undergoing
a successful radlofrequency catheter ablation (RFCA) of a single AP we have
compared the reported positive predictive value (PPVREP) of 4 ECG-ALG with
our own application of them In these Pts (PPV OURS)- We have developed a
new ECG-ALG and have blindly subjected to its diagnostic ability the 12-lead
ECG of 97 consecutive WPW Pts that had undergone a successful RFCA of a
single AP. Fluorographic views in RAO and LAO projections of the successful
RFCA sites were available for review. ECG-ALG are shown by the names
of the institutions. As shown In the table, our ECG-ALG Is superior, in our
hands, to the other 4. The sensitivity (SEN) and PPV of our ALG relative to AP
location is: arrteroseptal (AS) 100% & 100%, right anterolateral (RAL) 100% &
100%, right posteroseptal (RPS) 100% & 56%, left lateral (LL) 100% & 100%,
midseptaJ (MS) 79% a 100%, left posteroseptal (LPS) 88% & 100% coronary
sinus posteroseptal (CSPS) 80% & 67%, right posterior (RP) 86% & 100%, left
posterior (LP) 92% & 100%.
Sites
ECG-ALG
St George's
Aalst
CaBfornla Univ.
Oklahoma
Our own
9
8
7
10
S
PPVREP
86%
90%
95%
89%
_
PPVOURS
36%
50%
38%
40%
98%
AVLQor-(rS)LL*
V1+-
III+AS
III±RAL
IIIV2RSorRs
notch III/V1 MS
Q 4 notch II CSPS
smooth Q III RPS
V2 rS, ll+/± RAL, I I - RP
V1 RSor Ra
Q in III LPS
V1 R
QlnllILP
"lack ol Q In III suggests atypical LL, 'marked pre-exdtatlon with V1 - . AS
Conclusions: Reproduclblllty of ECG-ALG to localize the AP In WPW is
poor. Dif erences in the interpretation of the fluoroscoptc anatomy may explain
discrepancies. Each laboratory should validate an ECG-ALG according to their
own anatomic abstractions from the fluoroscopic views of catheters.
HEART RATE VARIABILITY
P2051
Linear Indices of heart rate variability In male
patients with mild heart failure due to coronary artery
disease: comparison of patients with and without
prior myocardlal Infarction
T. Ristimae, M. Thetlol, R. Teesalu. Department ol Cardiology, University ol
Tartu, Tartu, Estonia
Heart rate variability (HRV) has become an Important tool for indirect assessment of autonomic dysbalance as well as prognosis in various cardiac diseases.
In patients with congestive heart failure secondary to coronary artery disease
(CAD), diminished values of HRV have been shown previously. However, no
data concerning possible impact of different manifestations of CAD on HRV
indices In subjects with heart failure are currently available.
Subjects: 39 non-diabetic, age-matched male patients In NYHA functional
class M l (mean age 57.1 ± 8.7 yr.) were studied. 28 patients had documented
history of acute myocardial infarction (AMI) > 1 year ago (group I). In the
remaining 11 patients without prior AMI the ischaemlc etiology was evidenced
by coronary arteriography (group II). Patients with unstable angina and/or
arterial hypertension were not enrolled. All patients were in sinus rhythm. Two
groups were similar in respect to aspirin and nitrates administration during
the study. No other medication was used. There were no differences between
groups with regard to carcflothoracic ratio (0.47 ± 0.06 In group I vs 0.46 ±
0.04 in group II) and left ventricular ejection fraction, evaluated by M-mode
echocardiography (47.0 ± 13.0 In group I v s 4 4 . 8 ± 11.9 ml In group II).
Methods: 24-hour ECG monitoring was performed using 3-channel recorder
with modified V 2 , V s and III leads (SpaceLabs Medical FT 2000A™/FT 3000™),
Three time domain indices were considered: 1)SDANN (standard deviation of
all mean 5-minute normal sinus intervals over 24 hours) 2)pNN50 (percent
of difference between adjacent normal R-R intervals that are > 50 msec), 3)
r-MSSD (square root of the mean of the sum of the squares of differences
between adjacent normal R-R intervals). The following frequency domain
measures of HRV were evaluated: LF- with frequency range of 0.025-0.1 Hz;
MF-0.1-0.2 Hz; HF- 0.2-0.3 Hz (represents parasympathetic nervous activity),
and LF/HF ratio (as index of sympathetic nervous activity).
Results: No statistically significant dilerences (p < 0.05) between groups
were found, although group I demonstrated lower values of all HRV Indices.
Group I
SO ANN (msec)
pNN50(%)
r-MSSD (msec)
Total power (msec2)
LFfiraec2)
MFfraec 2 )
HFfmsec2)
LF/HF
118.8 ±27.5
3.6 ± 3 ^
24.1 ± 8 8
1935.2 ± 1076.6
752.9 ±502.5
130.6 ±107.6
75.3 ±74.7
13.4±76
Group II
123.0 ±35.1
4.2 ±3.2
26.6 ±10.3
2524.1 ±1488.2
996.3 ±657.9
163.0 ±147.1
76.9 ±50.0
18.1 ±13.3
Conclusion: We found that autonomic Input to heart in CHF-patients, as
assessed by linear Indices of HRV, is similar for clinically stable patients with
and without previous AMI. However, further studies are needed to evaluate
other methods of HRV as well as possWe relauonshlps between different
characteristics of neurohormonal modulation In this population.
P2052
Ability of heart rate variability in predicting
arrhythmic recurrences In patients with paroxysmal
atrlal fibrillation without structural heart disease
G.L Botto, W. Bonlni, T. Broffonl, G. Ferrari. Department ol Cardiology, S.
Anna Hospital, Como, Italy
The ability of heart rate variability (HRV) to predict paroxysmal atrial fibrillation
(PAF) recurrences was evaluated in 70 patients (pts) (41 male), mean age
53 ± 13 years, without structural heart disease. Each pts underwent 24-hour
Hotter, while In sinus rhythm, 4 weeks after a PAF episode. None of them was
taking dgltalis or antiarrhythmk: drugs during the follow-up. HRV parameters
were calculated in the time domain (TD) over 24 hours and In the frequency
domain (FD) as total (TP 0.017-0.50 Hz), low (LF 0.05-0.15 Hz) and high (HF
0.15-0.35 Hz) frequency components, using FFT analysis (Del Mar-Avionics
563). Five-minute epochs in a 30-mlnute period between 8 AM and 2 PM with
the pts in baseline condition, were analyzed. A mean follow-up of 357 ± 95
days was performed for identifying pts without (GrA 51 pts) and with (Gr.B, 19
pts) PAF recurrence, In order to define the risk prerJctor value of the considered
parameters.
TD
Mean FIR
(msec)
Gr. A 805 ± 9 1
Gr.B 8 0 3 ± 7 0
pval NS
FD
TPfmsec2)
SDANN
(msec)
SDNN
(rmec)
SO
(msec)
125 ± 3 7
123±38
NS
138±35
134 ± 3 8
NS
LFfrmec2)
HFfmsec2) LFnorm-U
r-MSSD
(msec)
pNN50
(%)
57.5 ±19.1 32-7 ±19.7 11.5± 13.6
54 1 ± 12.9 35.2 ±12.3 12.8 ±10.9
NS
NS
NS
HFnorrrMJ
LF/HF ratio
Gr. A 4040 ±5968 1510±2111 606±2756 025 ±0.12 0.15 ±0.11 2.47 ± £23
Gr B 2334 ±2207 460 ± 3 1 8 962 ±1089 0.16 ±0.09 0.29 ±0.16 0.70 ± 0.48
< 0.001
< 0 001
0.0O5
0.024
NS
pval NS
In the discrimination of the 2 groups a LF/HF ratio < 1.2 (p < 0.001) showed
89% sensitivity, 80% specificity, 63% positive and 95% negative predictive
value.
Frequency domain measures of HRV could be useful in the evaluation of
pts with PAF to predict recurrence after a single arrhythmic episode and could
allow to Identify a subgroup of pts at low risk of arrhythmic recurrence. A
simpato-vagal Imbalance, with Increase in the HF components, could play a
role in causing arrhythmic recurrences in pts with PAF without heart disease.
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