低射血分数患者非体外循环下冠状动脉搭桥术的应用

目的总结分析30例心脏超声检查射血分数〈30％的冠心病患者进行非体外循环冠状动脉搭桥术（OPCAB）的临床效果。方法2003年1月至2010年1月进行选择性OPCAB手术30例,全部经心脏超声检查测定射血分数为25-30（25．3±6．1）％。有心梗史23例,急性心肌梗死后1个月内6例,不稳定型心绞痛19例;心功能Ⅱ级7例、Ⅲ级18例、Ⅳ级5例。冠状动脉造影提示双支病变3例、三支病变21例、左主干6例。结果全部病例均完成OPCAB手术,平均远端吻合口（3．6±0．7）个,使用主动脉内球囊反搏3例。无死亡病例。有3例术后出现急性左心衰、低心排综合征,安放主动脉内球囊反搏后保守治疗好转。2例患者术后出现室颤,均复苏成功。结论低射血分数患者实施OPCAB手术有良好的可行性。     

Abdominal perfusion pressure and coronary arterial perfusion pressure in patients undergoing coronary artery bypass graft surgery

Abdominal perfusion pressure (APP) is defined as the difference between the mean arterial pressure and the intra-abdominal pressure (IAP). IAP elevation results in various side effects, including a decrease in coronary arterial perfusion pressure (CoPP). The present study analyzed the relationship between APP and CoPP in patients undergoing extracorporeal circulation (ECC). The patient population selected for the present study comprised 45 adult patients with a mean (± SD) age of 65.9±7.21 years (range 42 to 80 years), undergoing coronary artery bypass grafting with ECC and normovolemic hemodilution under general anesthesia. CoPP was measured as the difference between mean arterial pressure and pulmonary capillary wedge pressure. APP and CoPP were measured at seven time points (TPs): before surgery after the induction of anesthesia (TP1), during internal mammary artery preparation (TP2), 10 min after the heart-lung machine disconnection (TP3), after completion of the procedure but before sending the patient to the postoperative intensive care unit (TP4), 1 h after surgery (TP5), 6 h after surgery (TP6) and 18 h after the procedure (TP7). TP1 was considered to be the baseline value. IAP increased from TP3 to TP7; APP decreased at TP3 and TP4; there were no significant changes in CoPP. Significant correlations between APP and CoPP were observed at all TPs. Moreover, IAP correlated with CoPP at TP2 and TP4. Additionally, there was a strong overall correlation between APP and CoPP (P<0.001, r=0.9598). The present study arrived at two major conclusions: that ECC resulted in IAP elevation and that APP was strongly correlated with CoPP.     

Percutaneous transluminal coronary angioplasty in patients with reduced left ventricular ejection fraction: effects on myocardial perfusion and left ventricular response to exercise

Many patients with coronary artery disease treated by percutaneous transluminal coronary angioplasty (PTCA) have a history of previous myocardial injury resulting in a reduced left ventricular ejection fraction (EF). The effects of successful PTCA on myocardial perfusion and left ventricular function in these patients were compared to treatment in patients with normal left ventricular EF. There were 21 patients with a normal EF (mean EF 59 +/- 2%) (Group I) and 15 patients with reduced EF (mean EF 43 +/- 1%) (Group II). Before PTCA a similar degree of reversible myocardial ischemia was present on thallium scintigraphy. At peak exercise left ventricular EF in the Group I patients decreased by 4 +/- 1% compared to 8 +/- 1% in Group II. At one month following successful PTCA there was resolution of reversible myocardial ischemia in both groups. No changes in EF at rest were observed. At the same level of exercise as before PTCA the mean EF was 5 +/- 1% higher than the pretreatment value in Group I and 10 +/- 1% higher in Group II. Thus in this study reversible myocardial ischemia was associated with severe compromise in the left ventricular response to exercise which was substantially improved by PTCA.     

Effect of perioperative myocardial infarction on late survival in patients undergoing coronary artery bypass surgery

From the Seattle Heart Watch angiography registry, the baseline characteristics and late survival of 77 patients who sustained operative infarction (new Q waves) with myocardial revascularization were compared with 1790 patients who underwent coronary artery bypass without perioperative infarction. With the exception of coronary collateral vessels, which were less frequently seen in the patients with perioperative infarction, no baseline or operative characteristic distinguished between the two groups. Late survival was clearly adversely affected by perioperative infarction. Five-year survival was 76% in patients with perioperative infarction, compared with 90% in those with no perioperative infarction.     

非体外循环冠状动脉旁路移植术在低射血分数冠心病患者中的应用体会

目的:探讨非体外循环冠状动脉旁路移植术(OPCABG)在低射血分数冠心病患者中的应用体会。方法:对2015年11月至2017年3月,我院心胸外科行OPCABG手术的41例低射血分数的冠心病患者进行回顾性分析。患者均在全麻下行OPCABG手术,测定术前与术后8h血肌酐(SCr)、血尿素氮(BUN)、血小板(PLT)并进行比较,记录手术前、术后1周和3个月的左心室射血分数(EF)、左心室收缩期末内径(LVSD)和左心室舒张期末内径(LVDD),将结果进行比较;部分患者术后因低心排而应用主动脉内球囊反搏(IABP),监测使用前后血流动力学指标,如心率(HR)、心脏指数(CI)、收缩压、舒张压、中心静脉压(CVP)。结果:术后8h的Cr、BUN、PLT与术前比较无明显改变(P0.05)。术后1周EF与术前相比有所提高(P0.05),但LVSD和LVDD无明显变化(P0.05),但术后3个月后复查EF值与术后1周相比明显提高(P0.05),LVDD明显减小(P0.05),而LVSD未见明显变化(P0.05);术后部分患者因出现低心排而使用IABP,2h后舒张压、平均动脉压均增高,心率减慢,中心静脉压降低,心排血量及心脏指数增高(P0.05)。术后早期死亡2例(4.9%),分别为低心排综合征1例、多器官衰竭1例。术后39例康复出院。随访3个月,1例(2.6%)因脑血管意外死亡。结论:低EF冠心病患者实施OPCABG后近期效果显著,可明显提高EF,减小LVDD,且部分患者使用IABP 2h后可明显改善血流动力学指标进而保护心肌,但远期结果仍有待进一步观察。     

非体外循环下冠状动脉旁路移植术中应用正性肌力药物的相关因素

目的:观察和分析冠状动脉旁路移植手术(coronary artery bypass graft,CABG)中应用正性肌力药物的相关因素。方法:以2012年1月~2013年12月在北京市大兴区人民医院心脏中心接受非体外循环下CABG的患者630(男351,女279)例为研究对象。按术中是否应用正性肌力药物分为应用组(n=330)和未应用组(n=300)。通过回顾原始病历收集临床资料。需要应用正性肌力药物被定义为使用多巴胺剂量超过5μg/(kg·min)、任何剂量的肾上腺素或去甲肾上腺素、米力农。结果:确定了3个应用正性肌力药物的独立的相关因素:1心脏指数(CI)≤2.5 L/(min·m2);2左室射血分数(LVEF)≤35%;3左室舒张末压(LVEDP)≥25 mm Hg。结论:CI≤2.5 L/(min·m2)、LVEF≤35%和LVEDP≥25 mm Hg是增加非体外循环下CABG中应用正性肌力药物风险的独立相关因素。     

Thallium-201 myocardial perfusion scintigraphy to evaluate patients after coronary bypass surgery.

To determine the utility of thallium-201 stress scintigraphy in assessing the results of coronary bypass surgery, chest pain, stress electrocardiograms and scintigrams were evaluated in 27 patients postoperatively. These findings were compared with coronary angiographic data in which a significant postoperative lesion was defined as 75 percent or more stenosis in a graft, its distal vessel or in an ungrafted native vessel. As an indicator of postoperative coronary lesions, chest pain lacked sensitivity (60 percent) and was nonspecific (20 percent). The stress electrocardiogram had poor sensitivity (60 percent) and good specificity (86 percent) but was not helpful in six patients who had equivocal or suboptimal tests. The scintigram had good sensitivity (77 percent) and was highly specific for the diagnosis of coronary stenosis. It was significantly more specific than chest pain (P less than 0.01), gave excellent localizing information and added to the accuracy of both conclusive and inconclusive stress tests. In nine patients with preoperative stress scintigrams, comparison of pre- and postoperative studies reflected the éffects of bypass surgery on coronary perfusion. Scintigraphy is a useful technique for the noninvasive evaluation of the patient after coronary bypass surgery, and postoperative scintigraphy alone is of great value in documenting surgical results.     

Mortality in patients undergoing coronary artery bypass surgery after myocardial infarction

Data on 1,700 patients who underwent coronary artery bypass surgery without additional cardiovascular procedures at the Texas Heart Institute were analyzed, relating the interval between myocardial infarction and operation to early mortality (within 30 days after operation). Patients who underwent coronary artery bypass surgery after a recent infarction (within 2 months before operation) had a higher rate of early mortality (14.5 percent) than patients who had an old infarction (6.9 percent) or no previous infarction (4.1 percent). The interval between recent infarction and operation was most significant. Mortality in patients who underwent operation within the first 7 days after acute infarction (38.1 percent) was more than six times greater than in patients who were operated on 31 to 60 days after infarction (5.8 percent). Mortality of those operated on 8 to 30 days after infarction was 16.4 percent. Elective coronary artery bypass surgery after recent infarction is best accomplished after the first 30 days, when there is no increased risk to the patient. Emergency coronary artery bypass after complicated acute myocardial infarction may be a lifesaving procedure, but it is associated with increased early mortality and should be reserved for those whose condition has not responded to aggressive medical therapy.     

Mortality and morbidity after coronary artery bypass surgery related to pre-operative left ventricular ejection fraction: a follow-up study

OBJECTIVE: To study the pre-operative level of left ventricular ejectionfraction that may be indicative of an increased risk of earlyand late mortality and of recurrent angina pectoris and latenon-fatal myocardial infarction. MATERIAL AND METHODS: A total of 934 patients with known left ventricular ejectionfraction, 80 women and 854 men, were submitted to coronary arterybypass grafting at the Cardiovascular Unit of Rikshospitalet,Oslo, between August 1982 and December 1986. The closing datewas the 1st of January 1993, with a mean follow-up of time of7·4 years. The patients were divided in to four subgroupsaccording to their level of left ventricular ejection fraction:40%, 41–60%, 61–80% and >80%. The left ventricularejection fraction varied from 13–98%. A chi-square testof linear trend was used to calculate the relative risk betweenthe different subgroups. Cumulative survival was determinedusing survival curves. RESULTS: Early mortality. Twenty-five patients (2·7%) died within30 days of operation. Patients with left ventricular ejectionfraction 40% had a relative risk of 10·2 (1·9–17·2),for left ventricular ejection fraction 41–60% the relativerisk was 0·9 (0·1–8·9) and for leftventricular ejection fraction 61-80% the relative risk was 2·8(0·6–17·2). Left ventricular ejection fraction>80% was defined as relative risk=1. Late mortality. Altogether,174 patients died in the late phase (18·6%). For patientswith left ventricular ejection fraction 40% the relative riskwas 3·6 (2·8–10·9), for left ventricularejection fraction 41–60% the relative risk was 1·8(1·1–3·6),and for left ventricular ejectionfraction 61–80% the relative risk was 1·5 (0·9–2·8).Recurrent angina pectoris. A total of 138 patients developedrecurrent angina pectoris during the follow-up period, givingan incidence of 14·8%. Here, for left ventricular ejectionfraction 40% the relative risk was 0·5(0·2–13), for left ventricular ejection fraction 41–60% therelative risk was 1·0 (0·5–1·8) andfor left ventricular ejection fraction 61–80% the relativerisk was 1·2 (0·7–2·0). Late non-fatalmyocradial infarction. Altogether, 90 patients (9·6%)experienced non-fatal myocardial infarction in the late phase.For left ventricular ejection fraction 40% the relative riskwas 0·6(1·2–1·8), for left ventricularejection fraction 41–60% the relative risk was 1·0(0·5–2·0) and for left ventricular ejectionfraction 61–80% the relative risk was 0·7 (0·41–1·3).Cumulative survival. When pooled together, the cumulative survivalfor patients with left ventricular ejection fraction >40%was 95·9, 91·9 and 79% after 1, 5 and 10 years,respectively. For the patients with left ventricular ejectionfraction 40% cumulative survival was 87·5, 73·1and 55·2%, respectively. CONCLUSION: When the left ventricular ejection fraction was 40% or lower,there was a substantial increase in the risk of early mortalityin patients submitted to coronary artery bypass grafting. Asfor the risk of late mortality, there was a practically linearincrease in risk with falling values of left ventricular ejectionfraction. We found no difference in risk of developing recurrentangina pectoris or of late non-fatal myocardial infarction relatedto values of left ventricular ejection fraction.     

体外循环辅助心脏不停跳冠状动脉旁路移植术在低射血分数患者中的应用

目的 对97例射血分数（EF）＜0.30的冠心病患者的体外循环辅助心脏不停跳冠状动脉旁路移植术（OPCAB）进行总结分析.方法 选择97例EF＜0.30的高危患者,全部采用体外循环辅助心脏不停跳冠状动脉旁路移植术,其中男性55例,女性42例.术前测定射血分数0.18～0.29（0.240±0.031）.合并心肌梗死史42例,不稳定型心绞痛49例,支架置入治疗史16例.NYHA心功能Ⅱ级39例、Ⅲ级35例、Ⅳ级23例.冠脉造影提示双支病变21例、多支病变65例、左主干病变11例,合并轻、中度二尖瓣反流43例,合并室壁瘤13例,左室血栓2例.超声心动图检查提示左心室舒张末期内径53～76 （61.3±4.2）mm.结果 97例患者均完成手术,平均远端吻合口（3.7±1.1）个,使用主动脉内球囊反搏37例,均在手术中安放.住院死亡2例.1例脑梗塞导致左侧肢体偏瘫,未愈出院,1例肺梗塞,保守治疗好转.随访2～21个月.出院后死亡3例,3例有心功能不全表现,需要长期强心利尿药物治疗.其余患者心功能良好,未再次接受心导管术.结论 低射血分数患者实施体外循环辅助心脏不停跳冠状动脉旁路移植手术有良好的可行性和近期效果,能有效降低手术与麻醉风险.     

Effect of programmed ventricular stimulation on myocardial lactate extraction in patients with and without coronary artery disease

The arterial-coronary sinus lactate difference was measured in 17 patients after each step of a programmed ventricular stimulation protocol consisting of single, double, and triple extrastimuli, first at a basic drive cycle length of 600 msec, then at 400 msec, with an inter-train interval of 4 seconds. Four patients had no structural heart disease, four had an idiopathic dilated cardiomyopathy, and nine had coronary artery disease with a significant stenosis in at least one branch of the left coronary artery. Net myocardial lactate production during programmed ventricular stimulation was observed in three patients with coronary artery disease, but not in any patient without coronary artery disease. Among the patients who had coronary artery disease, net myocardial lactate production generally occurred in the patients who had more severe coronary artery disease. Exercise-induced ischemia, as demonstrated by a stress thallium-201 test, did not correlate with myocardial lactate production during programmed ventricular stimulation. Programmed ventricular stimulation, with a stimulation protocol typically used in many electrophysiology laboratories, is capable of inducing myocardial ischemia in at least some patients who have coronary artery disease. This finding suggests that myocardial ischemia may potentially influence the results of programmed ventricular stimulation in some patients with coronary artery disease.     

Noninvasive perfusion control by thallium-201 myocardial scintigraphy after coronary artery bypass surgery.

Thallium-201 myocardial scintigraphy, which has been shown accurate in the assessment of myocardial perfusion, was employed in the evaluation of 34 patients after coronary artery bypass surgery. In 28 patients (82.4%), there was a clear correspondence in the postoperative studies between the defects shown on scintigraphy and the coronary artery stenosis documented by arteriography. Thallium imaging after coronary artery bypass revealed an increased or newly developed scintigraphic defect in eight of 10 patients with recurrent angina. Follow-up arteriography in these 10 patients revealed occlusion or stenosis of the bypass graft in five, perioperative myocardial infarction in two, and increased stenosis of a preoperatively less occluded artery in two. In 24 patients with postoperative clinical improvement or relief of angina, 201Tl scintigraphy revealed complete normalization of thallium uptake in three, improvement of uptake in 17, and unchanged uptake defects in four.     

Usefulness of the ejection fraction response to dobutamine infusion in predicting functional recovery after coronary artery bypass grafting in patients with left ventricular dysfunction

Quantification of dysfunctional but viable myocardium has high prognostic value for improvement of left ventricular (LV) function after coronary artery bypass grafting (CABG). Dobutamine stress echocardiography (DSE) can assess viable myocardium by segmental wall motion changes during stress. However, analysis of wall motion is subjective with only moderate interinstitutional agreement (70%) and frequently overestimates functional improvement after CABG. In contrast, calculation of ejection fraction (EF) is less subjective and allows a more precise quantification of global contractile reserve. The aim of the study was to compare the prognostic value of EF response and segmental wall motion changes during DSE for the prediction of LV functional recovery after CABG. Forty patients underwent DSE before CABG. EF responses were assessed at rest, low-dose dobutamine, and at peak stress using the biplane disk method. Wall motion was scored using a 16-segment 5-point model. Resting radionuclide ventriculography (RNV-LVEF), performed before and 8 ± 2 months after CABG, was used as an independent reference. Five patients were excluded because of perioperative infarction or poor echo images. In 11 of 35 patients, RNV-LVEF recovered >5%. Improvement in EF during dobutamine infusion predicted RNV-LVEF recovery after CABG significantly better than segmental wall motion changes (72% vs 53%, p = 0.03). A biphasic EF response (i.e., improvement in ≥10% at low dose and subsequent worsening at peak stress) had the highest predictive value (80%) for late functional recovery. In conclusion, EF response to dobutamine infusion was superior to segmental wall motion changes in predicting RNV-LVEF recovery after CABG.     

Long-term prognosis after myocardial infarction in patients with previous coronary artery bypass surgery

A group of 205 patients hospitalized with myocardial infarction 2 to 162 months (mean 66) after bypass surgery and 205 control patients with myocardial infarction were compared and followed up for 34 +/- 25 months after hospital discharge. At baseline the postbypass group contained more men (p less than 0.03) and more patients with previous myocardial infarction (p less than 0.06), but the groups were otherwise comparable. Indexes of infarct size were lower in postbypass patients: sum of ST elevation, QRS score, peak serum creatine kinase (CK) (1,115 +/- 994 versus 1,780 +/- 1,647 IU/liter) and peak MB CK (all p less than or equal to 0.001). Postmyocardial infarction ejection fraction was 45 +/- 15% in the postbypass group and 43 +/- 15% in the control group (p = NS); in-hospital mortality rate was 4 and 5%, respectively (p = NS). When patent grafts were taken into account, the two groups were comparable in extent of coronary artery disease. At 5 years after discharge, cumulative mortality was similar in the postbypass and control groups (30 versus 25%, respectively, p = NS). However, postbypass patients had more reinfarctions (40 versus 23%, p = 0.007), more admissions for unstable angina (23 versus 18%, p = 0.04) and more revascularization procedures (34 versus 20%, p = 0.04) than did control patients. The total for these events at 5 years was 70% in the postbypass group and 49% in the control group (p = 0.001). Thus, although patients with previous bypass surgery who develop acute myocardial infarction have a smaller infarct, their subsequent survival is no better than that of other patients with acute myocardial infarction. They experience more reinfarctions and unstable angina. Previous bypass surgery is an important clinical marker for recurrent cardiac events after myocardial infarction.     

超声心肌声学造影评价冠状动脉狭窄程度对心肌灌注的影响

目的经冠状动脉超声心肌声学造影(MCE)检测基础状态下不同狭窄程度冠状动脉所供应心肌组织灌注状况。方法30例患者行选择性冠状动脉造影,按有无冠状动脉病变及病变血管狭窄程度,将所涉及的共93个心肌节段分为对照组(18个)和病变组(75个),其中病变组又分为轻度狭窄组(12个)、中度狭窄组(28个)、重度狭窄组(35个);超声声学造影剂由冠状动脉直接注入,完成MCE。对心肌灌注进行定性分析,并由心肌灌注时间强度曲线进行定量分析。结果112个心肌节段中有93个(83.0%)获得较满意图像,经视觉判断,病变组共75个心肌节段中,正常灌注的为58个(77.3%),低灌注为17个(22.7%),其中,轻度狭窄组均为正常心肌灌注。定量分析显示,重度狭窄组反映心肌灌注的3个参数值与对照组均存在明显差异(P<0.05);而轻、中度狭窄组各参数值与对照组无明显差异。结论基础状态下,狭窄程度>90%的冠状动脉病变,其心肌组织灌注水平较正常偏低;而当血管狭窄程度≤90%时,心肌灌注水平与正常相似。     

Coronary angioplasty in patients with prior coronary artery bypass surgery: all prior coronary artery bypass surgery patients and patients more than 5 years after coronary bypass surgery

Percutaneous transluminal coronary angioplasty (PTCA) has been used successfully in patients who have had prior bypass surgery (CABG) as a means of revascularizing the myocardium and avoiding repeat myocardial revascularization. However, angioplasty has been considered inappropriate as a means of dilating old saphenous vein grafts. The first section of this article details the authors' experience with PTCA of prior CABG patients, and the second section discusses the results of PTCA in the subset of patients 5 or more years after their last coronary bypass surgery. These data may make individuals rethink the appropriateness of PTCA in old saphenous vein grafts.