Kawaguchi A T, Kawashima Y, Ishibashi-Ueda H, Yanase M, Murakami T, Yagihara T, Kunieda T
Department of Cardiovascular Surgery, Osaka University School of Medicine, Japan.
J Thorac Cardiovasc Surg. 1993 Dec;106(6):1072-80.
A right-to-left interatrial shunt may prolong survival in patients with pulmonary hypertension presumably because of decompression of the right side of the heart. To test this hypothesis, 74 rats with monocrotaline-induced pulmonary hypertension were followed up weekly with cardiopulmonary exercise testing with a metabolic treadmill system for exercise tolerance, heart rate, oxygen uptake, carbon dioxide production, and survival until subsequent or induced death 8 weeks after monocrotaline treatment. In rats with an interatrial shunt, oxygen uptake and carbon dioxide production were higher and survival was better (n = 22, 27%) than those in rats without a shunt (n = 52, 0%; p < 0.05). For the prospective assessment of the effects of a reversed shunt, 24 other rats underwent a left superior vena cava-to-left atrial appendage anastomosis as a functional interatrial shunt (atrial septal defect group) 4 weeks after monocrotaline treatment when severe pulmonary hypertension had developed and were compared with an additional 25 rats receiving a sham operation. Both groups had exercise capacity depressed to the resting levels by 2 weeks after operation. Although transcutaneous oxygen levels decreased in response to exercise in the atrial septal defect group, uptake and carbon dioxide production stayed higher than those in the sham operation group with significantly better survival 4 weeks after operation (atrial septal defect 30% versus sham operation, 0%; p < 0.05), at which time a reversed shunt was determined with systemic embolization of intravenously infused microspheres. A right-to-left interatrial shunt, anatomic or functional, preserved basal metabolism and prolonged survival in rats with progressive pulmonary hypertension.
右向左心房分流可能会延长肺动脉高压患者的生存期，推测原因是它可使右心减压。为验证这一假设，对74只接受野百合碱诱导的肺动脉高压大鼠进行每周一次的随访，使用代谢跑步机系统进行心肺运动测试，以评估运动耐力、心率、摄氧量、二氧化碳生成量，并观察生存期，直至野百合碱治疗8周后自然死亡或诱发死亡。存在心房分流的大鼠，其摄氧量和二氧化碳生成量更高，生存期也比无分流的大鼠更好（n = 22，27%）（无分流大鼠n = 52，0%；p < 0.05）。为前瞻性评估逆向分流的影响，在野百合碱治疗4周后，当重度肺动脉高压形成时，对另外24只大鼠进行左上腔静脉至左心耳吻合术作为功能性心房分流（房间隔缺损组），并与另外25只接受假手术的大鼠进行比较。两组在术后2周运动能力均降至静息水平。虽然房间隔缺损组运动时经皮氧水平下降，但摄氧量和二氧化碳生成量仍高于假手术组，术后4周生存期明显更长（房间隔缺损组30%，假手术组0%；p < 0.05），此时通过静脉注射微球的全身栓塞确定存在逆向分流。解剖性或功能性右向左心房分流可维持大鼠进行性肺动脉高压时的基础代谢并延长生存期。
