Unpreconditioned free revascularized dynamic cardiomyoplasty. Is it feasible?
BACKGROUND
Cardiomyoplasty is a new ventricular bioassist device for myocardial failure. But there are some limitations in standard cardiomyoplasty, such as the orientation of the muscle and fiber and the efficiency of the contractile segment of the flap. Free revascularized latissimus dorsi flap may be a good idea for solving these problems.


METHODS
We designed a canine free latissimus dorsi flap by revascularizing the flap with the left internal thoracic vessels by micro-surgical technique. Group I (n = 3) as control was performed by standard cardiomyoplasty, and the Group II (n = 10) was performed by the revascularized method. The heart was then wrapped by the revacularized flap. Group II was divided into IIa (n = 6, no pre-treatment before revascularization) and IIb (n = 4, normal saline pre-treatment before revascularization) by the different preservation methods. Hemodynamic data were recorded.


RESULTS
Group I all survived the 8-week training period. But Group II, Group IIa and IIb, all died in 3 days, but survived more than 12 hours. The hemodynamic analysis in Group I did not show any significant change except left ventricular end diastolic pressure. It showed elevated left ventricular pressure when the cardiostimulator was ON.


CONCLUSIONS
According to the result of this experiment, it seemed impossible to get a satisfactory result of more than 3 days for free revascularized cardiomyoplasty at present. There were a lot of problems waiting to be solved, such as preservation method during ischemia, bulky mass of the flap, and the potential problem of neuromuscular atrophy.
Chen
Y S
YS
Department of Surgery, National Taiwan University Hospital, Taipei, ROC.
Yu
H Y
HY
Ko
W J
WJ
Chu
S H
SH
D000714:Anastomosis, Surgical; D000818:Animals; D018421:Cardiomyoplasty / Q000379:methods*; D004285:Dogs; D005240:Feasibility Studies; D019157:Ischemic Preconditioning, Myocardial; D011184:Postoperative Period; D013524:Surgical Flaps / Q000098:blood supply; D016277:Ventricular Function, Left; D017725:Ventricular Pressure