Objective: To investigate the value of Doppler echocardiography to diagnose heart transplant acute rejection in both patients submitted to the standard surgical technique (Group A), and to a new technique that preserves the size of the left atrium and leaves the right atrium intact (Group B).
Methods: 122 Doppler echocardiographic studies and endomyocardial biopsies were performed on 27 group A and 11 group B patients. Systolic measurements included left ventricular shortening fraction, left ventricular endsystolic stress and tricuspid ring systolic displacement. Diastolic indexes investigated were left and right ventricle filling and superior vena caval flow parameters.
Results: As expected, right atrium was smaller in group B(p < 0.01). In group A, peak early to late mitral flow velocity increased, as did the rejection grade; whereas in group B it decreased. Pericardial effusion was seen more frequently in group B rejectors (> or = 3) than non-rejectors (63% vs 27%, p < 0.01). Right heart pressures (right ventricular end-diastolic and right atrial mean) were slightly higher for group A and B rejector patients (p < 0.05 when comparing right ventricular end-diastolic pressure in rejector to non-rejector group B patients). Left ventricular isovolumic relaxation time was reduced during subsequent rejection episodes in the same patient, but sensitivity of 15% left ventricular isovolumetric relaxation time reduction for rejection > or = 3 diagnosis was only 22% with a specificity of 73%. No significant intrapatient changes were found in other Doppler-derived systolic or diastolic indexes.
Conclusion: Doppler echocardiography does not diagnose heart transplant acute rejection with enough reliability to avoid endomyocardial biopsies.