European Journal of Cardio-Thoracic Surgery, Vol 12, 25-30, Copyright © 1997 by European Association for Cardio-thoracic Surgery
Clinical data and histological features of transmyocardial revascularization with CO2-laser
N Gassler and HM Stubbe
Department of Thoracic and Cardiovascular Surgery, University Hospital Eppendorf, Hamburg, Germany.
OBJECTIVE: TMR is a modern therapeutic approach in the treatment of
patients with severe chronic ischemic cardiac disease. Clinical data from
world-wide over 1800 TMR-treated patients shows that TMR can improve
cardiac status in cases without preoperative congestive heart failure. The
mechanisms underlying beneficial TMR-effects are not well understood.
METHODS: The 61 patients of the Hamburg University TMR- trial were treated
with a CO2-laser. Clinically, both a 6 and a 12 months follow-up were
performed. Pathologically, hearts from four patients who died 3 (2
persons), 16 and 150 days after TMR, respectively, were examined by
trichrom-and immunostaining (anti- collagen types I and III). RESULTS: In a
6 months follow-up clinical data indicates that TMR was able to improve
clinical status in 50 of 61 laser-treated patients (82%), whereas 5 (8.2%)
did not show any benefit evaluated by CCS grading and six (9.8%) died. CCS
grade reduction was found in 22 patients with a 12 months follow-up (28
patients still in evaluation). Days 30, mortality amounted to 6.5%; late
mortality (over 30 days) was 3.3%. Histopathological investigations
revealed tissue remodeling comparable with different stages of wound
healing. The cicatricial tissue in the original laser-created channels
displayed a stronger immunostaining for collagen type III than for type I.
CONCLUSIONS: Clinically, TMR improves cardiac function in some patients
with severe ischemic cardiac disease, but pathophysiological data as well
as morphological features from human myocardium could not explain this
phenomenon. Therefore, TMR treatment should be used only as 'the last
chance' in patients with severe angina pectoris.
