الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
The present work was intended to evaluate the cardiac functions
and hemodynamics in children with a cute poststreptococcal
glomerulonephritis with variable degrees of severity. Moreover, to
uncover the relative role played by the different unfavourable stress
factors, including increased preload with or without an associated
increase in afterload, in impairing ventricular systolic and diastolic
function; if any. Also, to note whether the congestive manifestations
commonly observed in APGN represent a pure state of circutatory
congestion or congestive heart failure. Furthermore, to prove if there is
an impairment in myocardial functions in those patients who present
with clinical manifestation of heart failure.
It included fifty children with APGN admitted to Alexandria
University Children’s Hospital. The diagnosis of APGN was based on
the presence of hematuria, edema together with clinical and serolgical
evidence of recent streptococcal infection.
Patients were divided into three main groups according to the
presence of hypertension with our without heart failure: group one:
normotensives, group two: hypertensives without heart failure and
group three: hypertensives with heart failure. The patients had their
initial cardiac assessment within 72 hours of admission and a recovery
assessment two weeks after the initial one.
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In addittion to a thorough history taking, a full clinical
examination and laboratory investigations (including urine analysis,
ESR, C-RP, serum urea and creatinine), the cardiac assessment was
carried out including chest x ray P-A view, ECG and
echocardiography including Mmode, 2D and Doppler examination).
In our study no significant difference was noticed between G2
and G3 as regards SBP, DBP, HR and CNV.Only in G3, RR was
significantly increased together with the presence of gallop rhythm and
basal rales. Or,ly serum creatinine that was significantly increased in
both G2 and G3 but not significantly different between G2 and G3.
Both cardiothoracic ratios (initial and recovery)were not significantly
different between the three groups. PUlmonary venons congestion was
most severe in G3 and correlates positively with RR. The only ECG
abnormality was flat or inverted T waves in lead I, which was not
confined to one group, however, it was most common in G3 (33.3%).
Initial echo-Doppler study of patients in one group(PG-I)
compared with the control SUbjects revealed a significant increase in
LV walls (PW and IVS) and mass, LA dimensions and volumes, RA
dimensions, RV volumes, mitral and tricuspid valve diameters as well
as IVC minimal diameter in PG-I, whereas, there was an insignificant
increase in LV and RV systolic functions as well as the mitral and
tricuspid inflow parameters, however, IVC collapsibility was
significantly depressed in PG-1. Comparing initial and recovery echo-
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Doppler measurements, in addition to the aforementioned increase in
dimension and volumes, left and right ventricular systolic and diastolic
functions were insignificantly different. Moreover, the LA dimensions
and ejection indices did not return to the control levels by the time of
recovery evaluation. Comparing G2 with G3 revealed that LA end
systolic volume, aortic and tricuspid valve diameters were significantly
increased in G3, however , the ejection phase indices were
significantly depressed in G3 especially EF%, FS%, COP and AO PPET.
In some patients, transient mitral and tricuspid valve regurgitations
were noted in G1, G2 and G3, however they were more severe and
prolonged in G3, although they were clinically inaudible.
The CTR was positively correlated to RV and PV diameters,
whereas, T1 abnormality on ECG was correlated to diastolic
dysfunction (IVRT and LA-EF). The SV and COP were positively
correlated to increased LV preload while some diastolic function
parameters were negatively correlated to afterload (ASP).
Furthermore, heart failure was negatively correlated to LV syatolic
function indices whereas it was positively correlated to LA volumes,
duration of MR and severity of TR. Regression analyses revealed that
MR time of disappearance was highly dependent on both LA cross
sectional area and EF%, whereas TR time of disappearance was
highly dependent on both TR grade and LVD-V. Heart failure was
highly dependent on AO-FT, TR and MR grades.
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from our study we concluded that:
- Increased preload on the right side of the heart mediated by sodium
and water retention seems to be the main determinant of right sided
congestive manifestations without ventricular function impairment.
- Increased left ventricular preload is relatively well tolerated, in children
with APGN, through the effect of compensatory mechanisms including LA
and LV dilatation with concomitent increase in stroke volume and cardiac
output together with pulmonary venous congestion.
- No direct evidence indicating the occurance of myocarditis, however,
mild myocarditis can not be rolled out as a cause of systolic
dysfunction and! or MR.
- The encountered AV valvular regurgitations seem to be influenced by
different pathogenitic factors. The major determinants of transient MR
were LA dilatation from increased preload together with increased
after/oad that subsequently increase the mitral annular diameter in
addition to the possible mild myocardial damage in this poststreptococcal
event. Transient TR seems to be preload dependent,
however, heart failure may augment its severity.
- Echo-Doppler has proved to be superior over chest x ray or ECG in
evaluating cardiac functions and hemodynamics including valvular
regurgitation that should be followed up after clinical recovery as the
presistence of TR signifies presistence of hypervolemia while that of
MR signifies presistence of a relative myocardial dysfunction.
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RECOMMENDATIONS
- Early assessment of the cardiac performance by echocardiography is
of great value in early detection of cases with impaired systolic function
who should be managed promptly before the appearance of overt
heart failure.
- Proper adjustment of sodium and water balance, and frusemide
therapy, particularly in those patients with associated TR, could
alleviate the stress of hypervolemia on both sides of the heart and help
in saving, the cardiac compensatory mechanisms.
- Prompt control of hypertension helps in alleviating an additional
stress on cardiac functions and hemodynamics.
- Avoiding misdiagnosis of other causes of MR through the knowledge
that MR can occur in children with APGN.
- Prevention of streptococcal infection for 3-6 months could be helpful
in those patients with impaired systolic function and MR as a second
attack with nephritogenic streptococci, although rare, may increase the
risk of cardiac mortality.
- Further study of a common pathogenetic mechanism responsible for
the cardiac involvement in the two post streptococcal events; APGN
and ARF, is needed.