ABSTRACT
Fifty consecutive patients diagnosed as having dialted cardiomyopathy [DCM] by echocardiography [30 males, ages from 5 months to 4 years] were studied. Thirty age and sex matched normal subjects were selected as a control group. All cases and controls were subjected to detailed history taking and clinical examination. Investigations included chest X-ray [CXR], standard electrocardiogram [ECG] and detailed echocardiographic examination. Laboratory investigations included: Complete blood count [CBC], erythrocyte sedimentation rate [ESR], serum C-reactive protein [CRP], serum creatinine phosphokinase [CPK], lactic dehydrogenase [LDH] and immunological studies for the detection of enteroviruses and adenovirus specific IgG and IgM antibodies by ELISA technique. Recurrent respiratory infections and dyspnea were the most frequent clinical symptoms in cases with DCM. Tachypnea and hepatomegaly were the most frequent clinical signs, while displaced cardiac apex and muffled first heart sound were the most frequent cardiac signs. Apical pansystolic murmur was asuscultated in only 30% of cases while mitral regurge was detected by echocardiography in 100% of cases [P<0.001]. Increased cardio-throracic [C/T] ratio was found in all case with DCM with mean value of 68.82%. The percentage frequencies of patients with DCM and increased ESR, CRP or LDH were significantly higher than those with DCM and normal ESR, CRP or LDH [p< 0.001]. No significant difference could be detected between the percentage frequencies of patients with increased and those with normal CPK level. Control cases showed normal ESR, CRP, LDH and CPK levels. The mean pulmonary [Pul] artery diameter indexed to the root of body surface area, the mean indexed diameter of the root of the ascending aorta [Ao], left atrial diameter, left ventricular end diastolic and end systolic diameters, the means E-Point Septal Separation [EPSS] were found to be significantly higher in cases with DCM than in controls [P<0.001]. The mean shortening fraction [SF] was significantly lower in cases than in controls [p<0.001]. The mean Ao and Pul acceleration time [AT] and ejection time [ET] were significantly lower in cases with DCM than in controls [p<0.001]. The mean CPK and LDH levels were significantly higher in patients with raised ESR or CRP than those with normal ESR or CRP [p<0.001 and 0.01]. The mean EPSS was significantly higher in patients with raised ESR than those with normal ESR. Ao ET was significantly lower in patients with raised ESR or CRP than those with normal ESR or CRP. Pul ET was significantly lower in patients with raised ESR than those with normal ESR [p<0.05]. The percentage frequencies of adenovirus or enterovirus IgM positive cases were significantly higher in patients than in control cases together [P<0.001] and separately [p<0.01]. The mean serum CPK and LDH were significantly higher in patients with studied viruses IgM positive than those with viruses IgM negative [p<0.05 and 0.01]. The mean Ao AT, ET and Pul ET were significantly lower in patients with studied viruses IgM positive than those with viruses IgM negative [p<0.01, 0.05 and 0.01]. Enteroviruses and adenovirus are important factors in the pathogenesis of DCM in our children. Cases, with such viral infection tend to be more severe at presentation and have poorer ventricular function. Detection of viral specific IgM with the use of ELISA technique provides both simple and accurate method to detect infection with enteroviruses or adenovirus in our patients with DCM. Increased C/T ratio in the CXR should always alert to the diagnosis of DCM in children with repeated respiratory symptoms particularly in the absence of significant cardiac signs. Serum CPK level detection is usually sufficient to give an idea about ongoing myocardial injury in cases with DCM. ESR, CRP and LDH usually signify infection elsewhere that could trigger heart failure in the compensated patient