Download Reproducibility and Changes in Ejection Fraction (EF) Measured by

Medical Research Society
In conclusion, when advanced coronary heart
disease is so common, triage based solely on
conventional clinical risk factors is of
doubtful value. However, further study should
test the hypothesis that the anticipated extent
of revascularisation may help to identify
patients at highest risk of adverse events
whilst awaiting elective CABG.
7P
15 patients (79%)preferred S/C heparin, 2 (10.5%) preferred IV and 2 (10.5%) gave no preference at the end
of the treatment (p4.001, Chi square). VAS analysis
showed that S/C heparin was associated with significantly less pain at the injection site than IV heparin
(median 3mm (range 0-61) vs 12mm (0-97)dO.002,
(95% C.I. for difference 1, 15 Mann Whitney). Mobility
was significantly better with S/C heparin for the last
three days of treatment (median 4lmm (range 0-100) vs
72mm (23-99), p<0.005, (95% C.I.12, 43 Mann Whitney).
No significant difference in APTT and heparin levels
was found between the treatment modalities.
23 REPRODUCIBILITY AND CHANGES IN EJECTION FRACTION
(EF) MEASURED BY TRANSTHORACIC
ELECTRICAL BIOlMPEDANCE (TEB) IN HEALTHY SUBJECTS
In conclusion the subcutaneous administration of heparin
is preferred by patients with DVT.
HWK NG., TJ WALLEY’, Y TSAO* and AM BRECKENRIDGE
( introduced)
Dept. of Pharmacology and Therapeutics, University of Liverpool, L69 3BX.
EF(%) measured by TEB (BoMed NCCOM3-R7) is derived from systolic time
ratio (STR) through a regression equation based on comparison with
radionuclide MUGA scanning (Capan et al, Crit Care Med 1987, 15: 4). STR
determined by TEB agrees well with mechanophonocardiography(Thomas el
al, Br J Clin Pharmac 1990.30 304P). We studied the reproducibility of E F
measurement by TEB in 25 healthy volunteers (age range 21-52 years) by
estimating the cocfficient of reproducibility (CR) (Bland et al, Lancet 1986, i,
307). Immediate reproducibility was assessed by the CR of 2 successive
readings at supine rest (a). Day to day reproducibility was assessed by the CR
during the following protocol on 2 days: 10 min supine rest (b). 10 min passive
tilt (c), 5 min standing (d), 5 min sitting (e), during 2 min exercise on a bicycle
ergometer at 60W (1)and at 150W (g), sitting recovery from exercise at 2 min
Ih) and at 10 min (i). Results:
Mean f s.d. Mean dilTerence 2 s.d.
n
P
a.
5924
0.2f2.6
5.2
25
070
day 1
day 2
5.2
25
0.45
b.
59f4
5853
0.422.6
23
0.60
6.2
48f4
C.
-0.423.1
4924
12.0
25
0.80
0.326.0
4825
4826
d.
8.2
25
0.96
0.0 f4.1
e.
5026
5024
9.2
25
0.70
-0.4f4.6
f.
6025
5924
6.4
21
0.66
0.323.2
63f5
63f4
g.
12.8
24
0.65
-0.6f6.4
h.
6026
59f7
10.2
25
0.61
i.
-0.5251
50f6
5125
.,
.,
Data was incomplete during passive tilt (c) (2 subjects felt dizzy), exercise (g)
and shortly post exercise (h) (due to excessive body movement). There is no
significant difference in E F from day to day, though the CR is lowest at supine
rest. On each day, E F at supine rest (b) was significantly higher than during
passive tilt (c), standing (d) or sitting (e) (Pc0.0005). Similarly, E F at sitting
rest (e) was significantly lower than during exercise (f & g) and shortly postexercise (h) (P<0.0005),but returned to resting value after 10 min (i).
E F measured by TEB method is reproducible in healthy subjects in the short
term and from day to day. It can reliably detect phfiiological changes and may
be useful in pharmacological studies, but requires further clinical evaluation.
24
SUBCUTANEOUS VERSUS INTRAVENOUS ADMINISTRATION OF
HEPARIN IN THE TREATMENT OF DEEP VEIN THROMBOSIS; WHICH
DO PATIENTS PREFER? A RANDOMISED CROSS-OVER STUDY
AM ROBINSON, K McLEAN.M GREAVES and KS CHANNER
Departments of Cardiology & Haematology, Royal
Hallamshire Hospital, Sheffield S10 ZJF, England
Previous studies have shown that twice daily subcutaneous (S/C) calcium heparin and intravenous (IV) calcium
or sodium heparin have equal efficacy in the treatment
of deep vein thrombosis (DVT); there are, however, no
data to indicate which patients prefer.
20 patients with radiologically proven DVT were randomised to 3 days of either SC or IV heparin followed
by a further 3 days of heparin by the alternative route.
Visual analogue scales (VAS) were used to assess symptoms of leg pain, pain at injection site, and mobility.
On the third day of each treatment Activated Partial
Thromboplastin Time (APTT) and heparin levels were measured three hourly over a twelve hour period; otherwise
APTT was measured on a daily basis and adjusted as
necessary to maintain ratios between 14-2 x control.
19 patients completed both treatments, 1 patient was
withdrawn due to bleeding whilst receiving IV therapy
(APTT within normal range).
25
FLECAINIDE-RELATED ALTERATIONS IN THE
SIGNAL-AVERAGED ELECTROCARDIOGRAM: SIMILARITY
BETWEEN PATIENTS WITH OR WITHOUT VENTRICULAR
TACHYCARDIA
P KULAKOWSKI, Y BASHIR, S HEALD, V PAUL, D KATRITSIS,
M MALIK, AJ CAMM
Department of Cardiolo ical Sciences, St.George’s Hospital
Medical School, London 8W17 ORE, England
The effects of intravenous flecainide (F) (2mg/kg over IOmin)
on the time domain signal-averaged ECG (TdSAECG) and on
the spectrotemporal mapping (STM) of SAECG were examined
in 30 pts: 17 pts with documented sustained VT (10 postMl, 3
dilated cardiomyopathy, 4 normal heart) and 13 controls with
supra- ventricular arrhythmias and structurally normal hearts.
The result of TdSAECG was abnormal when 2 of 3 indices were
abnormal: total QRS (tQRS) duration> 120ms, duration of
signals under 40pV (LAS)>40ms, and the root mean square
voltage of the last 40ms of the QRS (RMS40) < 25pV. The result
of STM was abnormal when a normality factor in any lead
was <30%.
RESULTS: Prior to F administrationan abnormal tdSAECG was
recorded in 7 VT pts. Following F, 11 VT pts and 11 controls
demonstrated abnormal TdSAECG. F produced significant
changes in all TdSAECG indices (tQRS 117227ms vs
148+41ms, p<.OOl; I A S 30215ms vs 50220ms, p<.OOl;
RMS40 45244pV vs 16-c7pVV,
p<.OOl). In both the VT and the
control group changes were similar (differences NS): tQRS and
LAS durations were prolonged by 282 11% vs 2 5 r 14% and by
66270% vs 102+58%, RMS40 voltage was reduced by
45234% vs 53+25%, respectively. Before F infusion, STM was
abnormal in 8 VT pts and in 1 control. Following F, 6 VT pts and
2 controls had abnormal STM. The values of the normality
factor of STM were similar prior to and after F in all leads.
CONCLUSIONS: Intravenous F caused significant changes in
TdSAECG, which were similar in pts with and without VT and
independent of the underlying disease. The STM results
iemained stable. Thus, TdSAECG alterations represent F
induced unspecific conduction prolongation rather than
development of true cardiac late potentials.
MAIN, AND
’PING OF THE SIGNALAVERAGED ELECTROCARDIOGRAM
P KULAKOWSKI, M MALIK, 0 ODEMUYIWA, T FARRELL,
Y BASHIR, AJ CAMM
Department of Cardiological Sciences, St. George’s Hospital
Medical School, London SW17 ORE, England
The results of the time domain (Td), frequency domain (Fd),
and spectral temporal mapping (STM) analyses (ART software)
of the signal-averaged ECG (SAECG) were compared in 30
post infarction pts with sustained ventricular tachycardia (Vr)
and no bundle branch block, and in 30 matched post infarction
pts without VT. All TdSAECG indices differentiated between
patients with and without VT (p<O.OOl). The FdSAECG results