Arpesella G, Carraro U, Mikus P M, Dozza F, Lombardi P, Marinelli G, Zampieri S, El Messlemani A H, Rossini K, Pierangeli A
Cardiovascular Surgery, The S. Orsola Hospital, University of Bologna, Italy.
Ann Thorac Surg. 1998 Dec;66(6):1983-90. doi: 10.1016/s0003-4975(98)00906-0.
In dynamic cardiomyoplasty electro-stimulation achieves full transformation of the latissimus dorsi (LD); therefore, its slowness limits the systolic support. Daily activity-rest could maintain partial transformation of the LD.
Sheep LD were burst-stimulated either 10 or 24 hours/day. Before and 2, 4, 6, and 12 months after stimulation, LD power output, fatigue resistance, and tetanic fusion frequency were assessed. Latissimus dorsi were biopsied at 6 months, and sheep sacrificed at 12 months.
After 1 year of 10 hours/day stimulation LD was substantially conserved and contained large amounts of fast type myosin. From 2 months to 1 year of stimulation the power per muscle of the daily rested LD was greater than that of the left ventricle, being three to four times higher than in the 24-hour/day stimulation.
If extended to humans, these results could be the rationale for the need of a cardiomyostimulator, whose discontinuous activity could offer to patients the long-standing advantage of a faster and powerful muscle contraction.
在动态心肌成形术中，电刺激可使背阔肌（LD）实现完全转变；因此，其缓慢过程限制了收缩期支持作用。日常活动-休息可维持背阔肌的部分转变。
对绵羊的背阔肌进行每天10或24小时的爆发性刺激。在刺激前以及刺激后2、4、6和12个月，评估背阔肌的功率输出、抗疲劳能力和强直融合频率。在6个月时对背阔肌进行活检，12个月时处死绵羊。
每天10小时刺激1年后，背阔肌得到显著保留，并含有大量快肌球蛋白。从刺激2个月到1年，每日休息的背阔肌每块肌肉的功率大于左心室，比每天24小时刺激时高3至4倍。
如果将这些结果推广到人类，可能为需要心脏刺激器提供理论依据，其间断性活动可为患者提供更快且有力的肌肉收缩这一长期优势。
