Presentation, diagnosis, and medical management of heart failure in children: Canadian Cardiovascular Society guidelines

Pediatric heart failure (HF) is an important cause of morbidity and mortality in childhood. This article presents guidelines for the recognition, diagnosis, and early medical management of HF in infancy, childhood, and adolescence. The guidelines are intended to assist practitioners in office-based or emergency room practice, who encounter children with undiagnosed heart disease and symptoms of possible HF, rather than those who have already received surgical palliation. The guidelines have been developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and are accompanied by practical Recommendations for their application in the clinical setting, supplemented by online material. This work does not include Recommendations for advanced management involving ventricular assist devices, or other device therapies.

Myocarditis in infants and children: A review for the paediatrician.

Clinical myocarditis is uncommon in infants and children. The most common pathogen is Coxsackievirus B. The offending agent triggers an immune response, which results in myocardial edema with subsequent impairment of systolic and diastolic function. Newborns and infants are more severely affected because the immature myocardium has limited ways of adapting to an acute insult. Children typically present with sinus tachycardia and gallop on auscultation, cardiomegaly on chest x-ray and small voltages on electrocardiogram. The echocardiogram shows reduced ventricular function. Viral studies can isolate the pathogen. Myocardial biopsy is useful diagnostically, but carries a significant risk for the sick infant. The first line of treatment includes measures such as rest, oxygen and diuretics. Inotropic agents are useful in moderate to severe heart failure. The role of immunosuppressive therapy is not yet clearly established in the paediatric age group. Prognosis is guarded in newborns but more favourable in older children.

Correlation between electrocardiographic and ultrasonographic time-interval measurements in fetal lamb heart.

The objective of this study was to establish the echocardiographic modality that best correlates with electrical events in the fetal heart. No documentation on the relationship between electrical events recorded with a surface ECG and fetal M-mode or Doppler echocardiographic measurements is available. The following ultrasound tracings were recorded simultaneously with a surface ECG on six exteriorized near-term fetal lambs: 1) M-mode echocardiography of atrial and ventricular contractions; and 2) Doppler flow velocity waveforms in the right superior vena cava (SVC) either alone or 3) in association with those of the ascending aorta. In the SVC, the onset of the retrograde A wave and the beginning of the forward wave during ventricular systole were used as markers for the start of the P wave and QRS complex, respectively. For the simultaneous SVC and ascending aorta tracings, the beginnings of the A and of the aortic ejection waves were used as markers. On average, the atrioventricular interval was 84 ms longer than the PR interval with the M-mode, corresponding to an increase of 107%. A similar observation was made for the simultaneous Doppler signals from SVC and ascending aorta, but the difference between the atrioventricular and PR intervals was smaller, averaging 35 ms. When the SVC Doppler was taken alone, no significant difference was found between atrioventricular and ventriculoatrial compared with PR and RP intervals, respectively, and a strong correlation was found between the two methods of measurement, both for the atrioventricular (r = 0.91) and ventriculoatrial (r = 0.89) intervals. Doppler interrogation of the SVC alone and, to a lesser degree, of the SVC and ascending aorta are reliable indirect markers for the timing of electrical events of the fetal lamb heart in sinus rhythm.