Fietsam R, Lu H, Hammond R L, Thomas G A, Nakajima H, Nakajima H, Mocek F W, Spanta A D, Lavine S, Colson M
Division of Cardiothoracic Surgery, Wayne State University, Detroit, Michigan 48225.
J Card Surg. 1993 Mar;8(2):184-94. doi: 10.1111/j.1540-8191.1993.tb00371.x.
Skeletal muscle ventricles (SMVs) were constructed from the latissimus dorsi muscle in seven beagles. Following 3 weeks of vascular delay and 6 weeks of electrical conditioning, the SMVs were connected in series with the thoracic aorta using a valved aortic homograft for the efferent limb. The SMVs were stimulated to contract synchronously during diastole. Effective aortic diastolic counterpulsation was achieved in all dogs, with an average 24.2% +/- 15.3% improvement in diastolic pressure. In two animals surviving beyond 3 months, increase in SMV function was noted over time. Appropriate aortic homograft valve function was documented by echocardiogram. Acute reversible heart failure was induced with propranolol in one dog alive after 126 days. A 61.3% reduction in cardiac output and a 37.6% reduction in mean arterial blood pressure were achieved. During profound low cardiac output, SMV stimulation with 33 Hz and 50 Hz improved cardiac output by 16.9% and 17.8%, improved the tension time index by 14.9% and 16.1%, and improved the endocardial viability ratio by 34.1% and 34.1%, respectively. These results again demonstrate the long-term effectiveness of SMVs as aortic counterpulsators. A valve in the efferent limb of the SMV system functions appropriately over time and may improve the efficiency of the system.
在七只比格犬中，利用背阔肌构建了骨骼肌心室（SMV）。经过3周的血管延迟和6周的电调节后，使用带瓣主动脉同种异体移植物作为传出支，将SMV与胸主动脉串联连接。在舒张期刺激SMV同步收缩。所有犬均实现了有效的主动脉舒张期反搏，舒张压平均提高了24.2%±15.3%。在存活超过3个月的两只动物中，观察到SMV功能随时间增加。超声心动图记录了合适的主动脉同种异体移植物瓣膜功能。在一只存活126天后的犬中，用普萘洛尔诱发急性可逆性心力衰竭。心输出量降低了61.3%，平均动脉血压降低了37.6%。在严重低心输出量期间，以33Hz和50Hz刺激SMV，心输出量分别提高了16.9%和17.8%，张力时间指数分别提高了14.9%和16.1%，心内膜活力比分别提高了34.1%和34.1%。这些结果再次证明了SMV作为主动脉反搏器的长期有效性。SMV系统传出支中的瓣膜随时间功能正常，可能会提高系统效率。
