Sunderdiek U, Kalweit G A, Marx R, Schipke J D, Gams E
Department of Thoracic and Cardiovascular Surgery, Heinrich-Heine-University, Duesseldorf, Germany.
Cardiovasc Surg. 2003 Oct;11(5):389-95. doi: 10.1016/S0967-2109(03)00026-7.
Patients with significant risk factors are at increased risk of higher mortality and morbidity (9-16%) after CABG-procedures with cardiopulmonary bypass (CPB). When catheter interventions are not applicable and conventional CABG with CPB are considered to have an unacceptable perioperative risk, these patients (n=35) were scheduled for minimally invasive coronary artery bypass grafting (MIDCAB).
The risks leading to exclusion of conventional CABG procedures were: extremely impaired LV-function (EF<20%), severe pulmonary diseases, malignant carcinoma, compromised coagulation system, age >80 years with impaired physical constitution, redo-procedures after complicated initial operation, symptomatic descending thoracic aortic aneurysm, ongoing long-term intensive care treatment with unclear prognosis. All patients received the LIMA as a single graft to the LAD. One year follow-up was performed using transthoracic Doppler echocardiography at rest and during exercise.
In 20 patients incomplete revascularization was accepted. There was no mortality, while signs for myocardial infarction were seen in two patients. Twenty-nine patients (82%) showed clear improvement of clinical symptoms, one patient needed further conventional CABG. Nine to thirteen months postoperatively (mean 10.8+/-1.6 months), there were two deaths due to noncardiac reasons. Three of the survivors (n=33) had symptoms of angina pectoris. Exercise tests revealed an improved stress tolerance (NYHA class improved from preop. III-IV to postop. I-II). The IMA graft flow increased significantly with exercise in all patients. Flow patterns in both flow velocity and volume changed to diastolic-dominant, and the ratio of diastolic to systolic time-velocity integral of >1.5 excluded a graft stenosis.
In high-risk patients, with an increased likelihood of perioperative morbidity and mortality, the MIDCAB procedure can be performed accurately and safely. Even after incomplete revascularization of some high-risk patients, exercise tolerance was improved. Transthoracic Doppler echocardiography proved to be a clinically useful noninvasive method of assessing IMA graft function at rest and during exercise. Despite the small patient population, our late follow-up results suggest the potential benefit of MIDCAB for patients with otherwise inoperable heart disease.
具有显著风险因素的患者在接受体外循环（CPB）的冠状动脉旁路移植术（CABG）后，死亡率和发病率升高的风险增加（9 - 16%）。当导管介入治疗不适用且认为常规CPB辅助的CABG围手术期风险不可接受时，这些患者（n = 35）被安排进行微创冠状动脉旁路移植术（MIDCAB）。
导致排除常规CABG手术的风险因素包括：左心室功能严重受损（射血分数<20%）、严重肺部疾病、恶性肿瘤、凝血系统受损、年龄>80岁且身体状况不佳、初次手术复杂后的再次手术、有症状的降主动脉瘤、正在进行长期重症监护治疗且预后不明。所有患者均接受了左内乳动脉（LIMA）作为单独的移植血管移植至左前降支（LAD）。术后1年采用经胸多普勒超声心动图在静息和运动状态下进行随访。
20例患者接受了不完全血运重建。无死亡病例，2例患者出现心肌梗死迹象。29例患者（82%）临床症状明显改善，1例患者需要进一步进行常规CABG。术后9至13个月（平均10.8±1.6个月），有2例患者因非心脏原因死亡。33例幸存者中有3例有心绞痛症状。运动试验显示应激耐受性提高（纽约心脏协会心功能分级从术前的III - IV级改善为术后的I - II级）。所有患者运动时IMA移植血管血流量均显著增加。血流速度和血流量的模式均转变为以舒张期为主，舒张期与收缩期时间 - 速度积分比值>1.5可排除移植血管狭窄。
在围手术期发病率和死亡率增加可能性较高的高危患者中，MIDCAB手术可准确、安全地进行。即使一些高危患者进行了不完全血运重建，运动耐量仍有所改善。经胸多普勒超声心动图被证明是一种临床上有用的无创方法，可用于评估静息和运动状态下IMA移植血管的功能。尽管患者数量较少，但我们的晚期随访结果表明MIDCAB对其他情况下无法手术的心脏病患者可能有益。
