Association between myocardial mechanical dispersion and ventricular arrhythmogenicity in chagas cardiomyopathy

Chagas disease is a major health concern in Latin America. Ventricular arrhythmia (VA) is a hallmark of Chagas cardiomyopathy (CCM), associated with worse prognosis. The present study aimed to verify the association between myocardial mechanical dispersion (MD) and ventricular arrhythmogenicity in CCM. In a cross-sectional study, 77 patients (55.8 ± 10.4 years) with CCM were evaluated. Global longitudinal strain (GLS) and MD were assessed by echocardiography, derived from the speckle tracking technique. Myocardial MD was measured from the onset of the Q/R wave on electrocardiogram to the peak longitudinal strain in 16 segments of the left ventricle. Frequency and complexity of ventricular extrasystoles (VES) were assessed by dynamic electrocardiography. The density and complexity of VES and the presence of non-sustained ventricular tachycardias (NSVTs) increase as MD increases. In logistic regression, MD was the only variable associated with the presence of paired VES and ventricular bigeminy. In addition, both MD and GLS were associated with the presence of NSVT (both, p < 0.01), and MD was independently associated with NSVT (OR 1.04, 95% CI 1.004-1.201, p = 0.031). In CCM, MD is associated with a higher density and complexity of VES, including NSVT.

Plantar vein thrombosis and pulmonary embolism

Plantar vein thrombosis is an unusual and under-diagnosed condition that affects the plantar deep venous system. Current ultrasound investigation protocols for deep venous thrombosis neglect this entity. To our knowledge, there are only seven reports in the literature of 20 patients with plantar vein thrombosis detected with sonography without an associated pulmonary embolism. We present a case report of a patient with a plantar vein thrombosis associated with pulmonary embolism. Patients who present with pain and/or swelling of the foot should undergo ultrasound examination and careful evaluation for respiratory symptoms.

Clinical Significance of Ostial Great Saphenous Vein Reflux

PURPOSE

To evaluate anatomical and haemodynamic differences in patients with great saphenous vein (GSV) insufficiency by duplex scanning and air plethysmography.

MATERIAL AND METHODS

Duplex scanning and air plethysmography examination were undertaken. One hundred and twenty-one limbs in 91 patients were selected prospectively and divided into three groups: group A consisted of 27 controls; group B consisted of 25 limbs with GSV reflux and normal saphenous femoral junction (SFJ) and group C consisted of 69 limbs of patients with GSV and SFJ reflux. The presence of reflux and GSV diameter (SFJ, proximal and medial thirds of the thigh, the knee and medial and distal thirds of the calf) were assessed by duplex scanning. Air plethysmography was used to evaluate haemodynamic parameters: total venous volume (VV), venous filling index (VFI), residual volume fraction (RVF) and ejection fraction (EF).

RESULTS

There was a significant difference in GSV diameter among the three groups in almost all segments evaluated (e.g. medial thigh group A = 2.4 SD 0.3 mm; B = 3.2 SD 0.7 mm; C = 5.9 SD 2.2mm p<0.001, Anova). A significant difference in VFI was found among the groups (group A = 1.2 SD 0.5; B = 2.0 SD 1.4; C = 4.0 SD 2.5 p<0.05, Anova). VV was statistical different between groups A and C (p = 0.004) and B and C(p = 0.03). EF and RVF were comparable in all groups. The VFI was normal in 68% in group B comparing with only 14.5% in group C patients, finding a reflux more than 5ml/s (determined by VFI) in 26.1% of the group C patients, comparing with only 4% of group B patients (p<0.05).

CONCLUSION

We have shown that in patients with GSV reflux those with incompetence of the ostial valve of the GSV show greater venous reflux and dilatation of the saphenous trunk than those in whom the ostial valve is competent.

Diastolic function in Chagas' disease: An echo and tissue Doppler imaging study

AIMS

With the purpose of studying left ventricular filling in Chagas' disease (Chd), we evaluated 169 patients with Chd using echocardiography and Doppler and tissue Doppler imaging (TDI).

METHODS AND RESULTS

The patients were divided into four groups according to the pattern of left ventricular filling: Group 0--normal filling pattern, Group 1--abnormal relaxation, Group 2--pseudonormal flow pattern, and Group 3--restrictive pattern. All patients were submitted to TDI of the basal portion of the left ventricle's walls. Diastolic dysfunction was found in 21.3% of the patients, with a strong correlation between the worsening of diastolic function and ejection fraction (r = 0.78, P < 0.001). TDI septal e' wave measurement was the best method for the detection of any kind of diastolic dysfunction. Considering a cut-off point of 11 cm/s, a reduced e' wave value has 97% sensitivity, 84% specificity, 62% positive predictive value, and 99% negative predictive value. The septal E/e' ratio was the best index for the detection of advanced diastolic dysfunction. Considering a cut-point of 7.2, an elevated E/e' ratio has 100% sensitivity, 88% specificity, 54.2% positive predictive value, and 100% negative predictive value.

CONCLUSION

This study showed the characterization of the various patterns of left ventricle diastolic function by echocardiography and Doppler in Chagas' disease and the usefulness of TDI in the assessment of diagnosis of diastolic dysfunction in this disease.