Idiopathic ventricular tachycardia in infancy and childhood: A multicenter study on clinical profile and outcome

OBJECTIVES

The present study intended to evaluate the clinical profile and outcome in a large cohort of pediatric patients with idiopathic ventricular tachycardia (VT).

BACKGROUND

Ventricular tachycardia (VT) without underlying heart disease is rare in childhood. Limited information is available with regard to outcome and indications for long-term antiarrhythmic treatment.

METHODS

A retrospective multicenter study was conducted. Patient data were obtained from the individual centers using a standardized questionnaire.

RESULTS

Ninety-eight pediatric patients with episodes of VT in the absence of structural heart disease were included. Mean age at first manifestation of the arrhythmia was 5.4 years (range 0.1 to 15.1), with 27% of the patients having had VT already in infancy. Clinical symptoms or echocardiographic signs of left ventricular dysfunction were observed initially in 36% of the patients, of which one third (12% of the whole population) presented with severe symptoms (heart failure or syncope). After a mean follow-up of 47 months (range 12 to 182), no patient had died. Twenty-five patients had never been treated with antiarrhythmic drugs. Sixty-three patients were free of VT and did not take antiarrhythmic drugs at last follow-up. Prognosis was better when VT occurred during the first year of life (VT resolution in 89%) compared with VT occurrence beyond the first year of life (VT resolution in 56%: p < 0.01). The clinical profile was more favorable for patients with presumed right VT (VT resolution in 76%, symptoms in 25% of patients) compared with patients with presumed left VT, where VT resolution occurred in 37% and symptoms in 67% of patients (p < 0.01).

CONCLUSIONS

VT in children with a normal heart carried a good prognosis. Outcome was better after onset of VT during infancy and when VT originated in the right ventricle. A restrictive use of antiarrhythmic agents might be justified in a large proportion of these patients.     

Right ventricular dysfunction in hemodynamically stable patients with acute pulmonary embolism

Background

Echocardiography for risk stratification in hemodynamically stable patients with pulmonary embolism (PE) is well-established. Right ventricular dysfunction (RVD) is associated with an elevated mortality and adverse outcome. The aim of our study was to compare RVD criteria and investigate the role of elevated systolic pulmonary artery pressure (sPAP) in the diagnosis of RVD.

Methods

We retrospectively analyzed the echocardiographic and laboratory data of all hemodynamically stable patients with confirmed PE (2006-2011). The data were compared with three different definitions of RVD: Definition 1: RV dilatation, abnormal motion of interventricular septum, RV hypokinesis or tricuspid regurgitation. Definition 2: as with definition 1 but including elevated sPAP (> 30 mmHg). Definition 3: elevated sPAP (> 30 mmHg) as single RVD criterion.

Results

A total number of 129 patients (59.7% women, age 70.0 years (60.7/81.0)) were included in this study. Median Troponin I level was measured as 0.02 ng/ml (0/0.14); mean sPAP 33.9 ± 18.5 mmHg. The troponin cut-off levels for predicting a RVD of the 3 RVD definitions were in definition 1-3: > 0.01 ng/ml, > 0.01 ng/ml and > 0.00 ng/ml. Analysis of the ROC curve showed an AUC for RVD definitions 1-3: 0.790, 0.796 and 0.635.

Conclusions

The combination of commonly used RVD criteria with added elevated sPAP improves the diagnosis of RVD in acute PE. Troponin I values of > 0.01 ng/ml in acute PE point to an RVD.