Off-pump coronary artery bypass grafting using in-situ right internal thoracic artery extended with radial artery as I-composite graft

OBJECTIVE: The purpose of this study is to assess the feasibility of utilizing the proximal right internal thoracic artery (RITA) extended with the radial artery (RA) as I-composite graft (RITA-RA graft) in off-pump coronary artery bypass grafting (OPCAB), which preserves the left internal thoracic artery to the left anterior descending artery as an isolated graft and the ascending aorta no-touch technique. METHODS: Between January 2002 and August 2006, 37 patients (aged 67.4+/-7.5 years, 86.5% male) underwent OPCAB using RITA-RA graft. All grafts were harvested in a skeletonized fashion. RITA transected at the middle portion was extended with entirely dissected RA. RITA-RA graft was anastomosed to 1 or 2 lateral artery in a parallel sequential pattern. RESULTS: The total number of distal anastomoses of RITA-RA graft was 48. The early graft patency rate was 97.9%. Five cases (13.5%) needed intra-aortic balloon pumping support during operation. Only 1 patient (2.7%) required ventilator support longer than 24 hours. The percentage of patients requiring homologous blood transfusion was 13.5%. There was no cerebrovascular accident or mediastinitis in the postoperative course. All patients were discharged from hospital. CONCLUSIONS: OPCAB using RITA-RA graft is feasible and safe. It provides satisfactory early clinical and angiographic outcomes.     

Off-pump coronary artery bypass grafting using graft to coronary shunt for acute coronary syndrome

We developed graft to coronary shunt during off-pump anastomosis. Proximal anastomosis of saphenous vein graft (SVG) was done formerly, and vinyl chloride tube, 5 cm long and 2 mm in diameter, was inserted into SVG. Another end was inserted into coronary artery, and continuous suture around the tube was performed before removing the tube. This technique is fit to use for the anastomosis between SVG and #3. Because the tube is easily inserted into those parts without injury of intima, and distal right coronary artery needs enough blood supply. After the revascularization of left anterior descending artery and #3, the heart can be displaced to expose circumflex artery. We adopted this technique to 3 patients with acute coronary syndrome (ACS). Though this technique is not adopted for the patients having stenosis on #4, we conclude that SVG to coronary shunt could be a important part of the strategies of off-pump coronary artery bypass grafting (OPCAB) for ACS patients.     

Off-pump coronary artery bypass

OBJECTIVES: Off-pump coronary artery bypass grafting (CABG) on the beating heart has become popular procedure in cardiac surgery and its initial results appeared favorable. We report our early and mid-term results of off-pump CABG performed at Shin-Tokyo Hospital. METHODS: Medical records of patients undergoing off-pump or conventional on-pump CABG from September 1, 1996, to August 31, 1999 were retrospectively reviewed. Patients underwent off-pump CABG were further classified into 2 groups; MIDCAB (Off-pump CABG for single vessel revascularization via a small skin incision) and OPCAB (off-pump CABG mainly approached via midline sternotomy) group. Their preoperative, perioperative, and follow-up data were collected and analyzed. RESULTS: Among a total of 995 cases of CABG, 194 cases were off-pump CABG (male/female 142/52, mean age 66.9). The mean number of distal anastomoses in off-pump CABG was 1.9 +/- 0.9 (1.0 +/- 0.0 in MIDCAB and 2.3 +/- 0.7 in OPCAB), which was significantly fewer than in on-pump CABG (3.6 +/- 1.1), with p < 0.0001. Intubation time (5.3 +/- 5.7 hours in off-pump CABG vs 13.1 +/- 24.2 hours in on-pump CABG), ICU stay (1.7 +/- 1.1 vs 3.2 +/- 3.0 days), and postoperative hospital stay (14.0 +/- 7.9 vs 18.1 +/- 12.1 days) in off-pump CABG were significantly shorter than in on-pump CABG (p < 0.0001). In the off-pump CABG group, there were no in-hospital deaths and 14 major complications, fewer than in on-pump CABG (8 hospital deaths and 114 major complications). Postoperative angiography before hospital discharge was conducted in 80 patients (41.2%) and showed 2 occlusions, giving a graft patency rate of 98.6% in the off-pump group. During follow-up (0.9 +/- 0.6 year) period, there were 5 non-cardiac deaths and 20 cardiac events in the off-pump group. The actuarial survival rate at 36 months was 94.6% for off-pump CABG, showing no significant difference from the rate for conventional CABG patients (95.2% at 36 month, p = NS) The event-free rate was 84.0% at 36 months in off-pump CABG patients; however, which was less favorable than on-pump CABG patients (88.0% at 36 months, p < 0.05). CONCLUSIONS: Both in-hospital and mid-term results for off-pump CABG patients were acceptable. Isolated CABG can thus be safely performed without cardiopulmonary bypass. Advances in coronary stabilization have contributed to these improved results. The observed long-term cardiac events may be related to incomplete revascularization.     

非体外循环下冠状动脉旁路移植术

目的 报告微创非体外循环冠状动脉旁路移植术(OPCABG),探讨其手术指征及外科处理要点。方法 回顾性总结5例OPCABG的临床资料。结果 5例顺利完成非体外循环冠状动脉旁路移植术。随访3～4个月,无死亡,无明显心绞痛及心肌缺血表现。结论 对于选择的患者,OPCABG安全、经济、有效,是一种值得推广的微创心脏手术方法。     

非体外循环下冠状动脉旁路移植术

目的 总结110例非体外循环心脏跳动下冠状动脉旁路移植术经验，探讨其手术适应证、优缺点及手术方法。方法 常温、全身麻醉，胸正中切口，非体外循环心脏跳动下，应用特殊心表固定器行冠状动脉旁路移植术，平均搭桥3．9支，血管桥为乳内动脉、大隐静脉及桡动脉。结果 全组无手术死亡，术后心绞痛症状消失。手术时间平均为210min，术后气管插管时间平均为4．8h。术后住院时间平均为10d，住院费用平均为4．4万元。其中3例术中出现不可逆血压过低、室颤而转为体外循环冠状动脉旁路移植术。结论 非体外循环心脏跳动下冠状动脉旁路移植术是一种安全、有效的治疗方法。特别适合于老年及心功能差的患者，可减少体外循环并发症，缩短术后住院时间，降低住院费用，但不能完全替代体外循环旁路移植术。     

Role of radial artery graft in coronary artery bypass grafting

The use of the radial artery (RA) as a coronary artery bypass graft has assumed a revival and thus a multitude of issues have arisen surrounding the routine and widespread use of this conduit in myocardial revascularization. There has been no uniformity regarding harvest techniques, assessment of the adequacy of hand collateral circulation, antispasm protocols, selection of target vessels, and the site of proximal anastomosis. It is widely believed and practiced that the RA should be harvested as a pedicle graft and preferably be used to bypass critically stenosed (>70% stenosis) coronary arteries. It is used either as a free graft with proximal anastomosis to the ascending aorta or as a composite arterial graft along with the left or right internal thoracic artery. The patency of RA grafts depends on the severity of the target coronary artery stenosis and target artery location rather than its use as an aortocoronary conduit or composite graft. In this article, we reviewed the current knowledge regarding the use of RA grafts as a coronary bypass conduit in an attempt to suggest a few acceptable strategies concerning the above issues in a given clinical scenario.     

不停跳冠状动脉旁路移植术在左主干病变病人中的应用

目的 探讨不停跳冠状动脉旁路移植术（0PCAB）在左主干病变病人中应用的可行性和特点。方法 2002年5月至2006年5月，97例伴有左主干病变的冠心病病人施行了OPCAB，同期为86例伴有左主干病变的冠心病病人行体外循环下的冠状动脉旁路移植术（CABG）。对两组病人术前、术后的临床资料进行对比分析。结果 OPCAB和CABG组术前平均年龄（68．1±4．9）岁对（64．3±6．5）岁，P〈0．05；术前慢性阻塞性肺疾病史10．3％对2．3％，P〈0．05；术前肌酐高于正常者5．2％对0，P〈0．05；术前脑梗塞病史12.4％对3．5％，P〈0．05。术后OPCAB和CABG组病死率为1．03％对1．16％，P：0．93；房颤发生率14．4％对27．9％，P=0．02。结论 对伴有左主干病变的冠心病病人行OPCAB临床效果良好。     

Prevention of radial artery graft vasospasm after coronary bypass

Background. Pharmacologic prophylaxis for prevention of notorious radial artery (RA) spasm is critical because of the increasingly routine use of the RA conduit during coronary bypass. Therefore, we investigated the vasodilatory effect of calcium antagonist in combination with nitroglycerin (NTG) RA segments.

Methods. We evaluated the vasodilatory effect of nifedipine alone, verapamil alone, diltiazem alone, NTG alone, and calcium antagonist in combination with in endothelin-1 (ET-1)-, angiotensin II (AII)-, 5-hydroxytryptamine (5-HT)-, and norepinephrine (NE)-precontracted human RA rings mounted in organ baths.

Results. Nifedipine (10⁻⁵ M) alone, diltiazem (10⁻⁵ M) alone, verapamil (10⁻⁵ M) alone, and NTG (10⁻⁵ M) alone showed maximum vasodilatory effect in either 10⁻⁷ M ET-1-, 10⁻⁷ M AII-, 10⁻⁵ M NE-, or 10⁻⁴ M 5-HT-precontracted RA segments. The 10⁻⁵ M NTG alone-induced vasodilation (88.5% ± 7.7%) in ET-1-precontracted segments was the highest vasodilation (ANOVA, p = 0.0008) among NTG alone-induced vasodilatory effects in RA. The relaxing effect of any of the calcium antagonists alone varied from 32.7% ± 13.2% to 76.5% ± 20.5% in RA precontracted with different vasoconstrictors. Nearly 200% vasodilation was observed with calcium antagonist in combination with NTG in AII-precontracted vessels. Nonetheless, the vasodilatory effect of calcium antagonist in combination with NTG in RA segments precontracted with different vasoconstrictors other than AII was nearly 100%.

Conclusions. A calcium antagonist in combination with NTG is more potent than calcium antagonist alone or NTG alone in prevention of human RA vasospasm after coronary bypass.     

Experience with the radial artery graft for coronary artery bypass.

Forty-eight radial artery grafts and 22 saphenous vein grafts in 37 patients undergoing coronary bypass procedures were studied early postoperatively. Most of the saphenous vein grafts were patent, but one-half of the radial artery grafts were occluded. Failure of the radial artery grafts could not be attributed to unfavorable runoff in the recipient vessels. Radial arteries carrying higher flows and those to vessels having more severe degrees of proximal stenosis occluded with a higher frequency. The radial artery should not be used for coronary bypass.     

Off-pump redo coronary artery bypass grafting

BACKGROUND: Conventional redo coronary artery bypass grafting is associated with significant morbidity. The danger of reoperation is mainly in reopening the sternum and in the manipulation of the heart and the old grafts. Therefore, off-pump redo coronary artery bypass grafting with a patient-specific approach in selected cases seems an ideal technique. METHODS: Between October 1995 to September 1999, 50 patients with mean age of 61.8+/-8 years underwent reoperative coronary artery bypass grafting without cardiopulmonary bypass. Isolated left internal mammary artery (LIMA) to left anterior descending artery (LAD) anastomosis was carried out in 25 cases through left anterior minithoracotomy. In 1 patient LIMA was grafted on a previous vein graft to LAD, which was critically stenosed proximally but distal anastomosis was patent. In another case LIMA was grafted to Ramus intermedius branch. Midsternotomy approach was used to carry out LAD and right coronary artery grafting in 21 cases. In 2 patients a posterolateral thoracotomy approach was used to bypass obtuse marginal branches without cardiopulmonary bypass; in these cases proximal anastomosis was performed on the descending aorta. RESULTS: Mortality rate was 4% (2 deaths). Two patients sustained perioperative myocardial infarction. No patient was reexplored for hemorrhage and 38 patients did not require homologous blood transfusion. Sixteen patients underwent check angiogram and all of them were found to have patent redo grafts. Cardiac recovery room stay was 22+/-7 hours and hospital stay 5+/-2 days. CONCLUSIONS: In selected patients, reoperative coronary artery bypass grafting can be performed without cardiopulmonary bypass with a low perioperative morbidity and mortality and satisfactory graft patency.     

Endoscopic harvesting of the radial artery as a coronary artery bypass graft

With an endoscopic approach we harvested the radial artery as a coronary artery bypass graft, using two transverse 2-cm incisions in the forearm. There were no complications in the forearm and hand. The short-term results of the radial artery graft were good.     

非体外循环下双侧乳内动脉Y型桥的冠状动脉旁路移植术125例

目的总结非体外循环下采用双侧乳内动脉Y型桥进行完全心肌血运重建的冠状动脉旁路移植手术125例的近期疗效。方法2002年10月至2005年12月,完成125例不停跳非体外循环下双侧乳内动脉Y型桥的冠状动脉旁路移植手术,术中采用带蒂半骨骼化的方法分别取材左、右侧的乳内动脉,将左、右乳内动脉端侧吻合成Y型桥;在非体外循环下,应用序贯吻合的方法进行冠状动脉搭桥手术。结果全组125例患者共搭桥413支,平均搭桥支数3．3支／例。术中流量测定桥血管均通畅。全组患者无围手术期死亡。结论非体外循环下双乳内动脉Y型桥的冠状动脉旁路移植手术是安全、有效的方法,可以实现全动脉化的完全心肌血运重建,又避免手术中对升主动脉的操作,近期效果满意。     

Off-pump coronary artery bypass grafting in Japan

The number of coronary artery bypass grafting (CABG) procedures has reached more than 20,000 per year in Japan, and the operative mortality rate has decreased to less than 1.5% including emergent surgery. The mortality and morbidity rates of CABG are still high in patients with risk factors such as cerebrovascular disease, chronic renal failure on hemodialysis, atheromatous and calcified ascending aorta, and older age when cardiopulmonary bypass is used. Minimally invasive direct coronary bypass on a beating heart through a small left lateral anterior thoracotomy, in which the left internal thoracic artery (LITA) is used to revascularize the left anterior descending artery, was introduced for high-risk patients with single-vessel disease in the mid-1990s, although is not widely performed at present. Since the late 1990s off-pump coronary artery bypass grafting (OPCAB) has been widely performed as a treatment for multivessel disease through a median sternotomy with the evolution of stabilizers and apical suction devices, refined anesthetic management, and sophisticated surgical techniques. In 2004, 60% of all CABG procedures in Japan were performed without cardiopulmonary bypass. Due to competition from percutaneous coronary intervention with drug-eluting stents and better long-term outcomes, CABG with arterial grafts alone was carried out in 52% of total cases and in 66% of OPCAB cases. OPCAB is becoming the standard CABG in Japan.