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Long-term cardiac allograft valves after heart transplant are functionally and structurally preserved, in contrast to homografts and bioprostheses.

BACKGROUND AND AIM OF THE STUDY
Homograft valves undergo degenerative changes over time, which finally lead to functional deterioration. Immunological events are believed to play a pivotal role in this process. To further evaluate this hypothesis, the valvular morphology and function, as well as comorbidities predisposing to deteriorative processes, were evaluated in patients who had undergone heart transplant more than 10 years previously.


METHODS
In a consecutive cohort of 146 patients (125 males, 21 females; mean age at transplant 43.8 +/- 11.2 years), heart and valve function were assessed by color Doppler echocardiography at a mean of 5306 +/- 987 days after heart transplant. Evaluated parameters included chamber dimensions, cardiac function, valvular morphology/function, and concomitant diseases.


RESULTS
Atrial and ventricular dimensions were within normal ranges for the left atrium (LA; n=7), right atrium (RA; n=7), left ventricle (LV; n=143) and right ventricle (RV; n=119). Slight enlargements occurred in the LA (n=138), RA (n=137), LV (n=1) and RV (n=11), while significant enlargements were seen in the LA (n=1), RA (n=2), LV (n=2), and RV (n=16). With regard to cardiac function, the ejection fraction (EF) was 63.9 +/- 4.9%, left ventricular isovolumic relaxation time (IVRT) 85.04 +/- 14.64 ms, fractional shortening (FS) 34 +/- 12%, and pulmonary artery systolic pressure (PASP) 29.81 +/- 6.4 mmHg. Valvular regurgitation (grade > or =2) was present in 34 patients (31 tricuspid valves, three mitral valves). No patients presented with aortic valve regurgitation. Concomitant conditions with a potential impact on calcium balance/valvular deterioration included immunologic/chronic inflammatory diseases (n=6), malignancies (n=12), kidney (n=41), cardiovascular system (n=39) and thyroid/parathyroid (n=12).


CONCLUSION
During the long term after heart transplant, heart valves were characterized by normal morphology and function in the majority of cases. Although most patients presented with concomitant conditions strongly predisposing for valvular deterioration/calcification, sole immunosuppressive/anti-inflammatory therapy appears to prevent these processes in heart transplant patients.