الفهرس 
Left ventricular hypertrophyOnly 14 pages are availabe for public view
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Abstract
It is usually considered difficult or impossible to make the
electrocardiographic diagnosis of left ventricular hypertrophy in the face of
left bundle branch block.
The distinction between the two situations, however, may be crucial,
as left ventricular hypertrophy is an independent risk factor for increased
cardiovascular morbidity and mortality.
The aim of this work is to find, if any, an electrocardiographic
clue(s) to the diagnosis of left ventricular hypertrophy in presence of left
bundle branch block.
Two groups of patients were included in this study, 50 patients each.
The first group (group1) included patients with left bundle branch block
and no left ventricular hypertrophy by M-Mode echocardiography. The
second group (group II) included patients with left bundle branch block
and left ventricular hypertrophy.
All patients were subjected to thorough history taking, clinical
examination, resting 12-leads electrocardiography and M-mode
echocardiography.
Summary
08
Comparing groups I and II, a significant increase of voltage in group
II was occured in most leads more than in group I. In addition, significant
more incidence of left axis deviation and left atrial changes were occured
in group II. Remembering that both groups shared a common feature
which is left bundle branch block, this difference must be attributed to the
presence of left ventricular hypertrophy (Table 3 and 4).
Sensitivities of these features for electrocardiographic diagnosis of
left ventricular hypertrophy in the presence of left bundle branch block
were calculated, and the results were values range from 26 %to 68% The
four criteria (SV3 > 25mm , SV3 + RaVL > 30mm , R + S in any
precordial lead > 45mm and QRS duration ≥ 0.16 msec) were the most
sensitive ( 55% - 68% ) (Table 5).
All the selected ECG parameters had very high specificity
ranging from 75 % to 100% except for QRS duration > 0.16 msec
which had very low specificity (35%) (Table 5).
In the present study the following ECG criteria had
reasonable sensitivities and specificities and hey might be
suggested to be used in the diagnosis of of LVH in the presence
of LBBB.
- SV3 > 25mm (sensitivity 68 % and specificity 78%)
Summary
08
- SV3 + RaVL > 30 mm (sensitivity 62 % and specificity 100%)
- R + S in any precordial lead > 45 mm (sensitivity 55% and
specificity 100%)
- Left atrial abnormality (sensitivity 40 % and specificity 82%)
- RaVL > 11mm (sensitivity 28 % and specificity 100%)
- SV3 > 25 mm and SV2 > 30 mm (sensitivity 46 % and
pecificity 100%).
The results were tabulated and statistically analyzed.