Diagnostic value of 123I-phenylpentadecanoic acid (IPPA) metabolic and thallium 201 perfusion imaging in stable coronary artery disease

The diagnostic value of ¹²³I-phenylpentadecanoic acid (IPPA)metabolic cardiac imaging was studied in a group (n=29) of patientswith angiographically confirmed CAD using single photon emissioncomputed tomography (SPECT). A symptom-limited exercise testwas first done with IPPA, and 2 days later with thallium. Medicationswere not withheld during testing. Fourteen healthy control subjectsparticipated in parallel IPPA and 15 in thallium tests. Data acquisition and output were comparable in the two imagingmodalities. By testing various relatively simple criteria forabnormality we found that the semiquantitative interpretationwas more accurate than the visual readings. The best compromiseof accuracy with the scored criteria consisted of a sensitivityof 86% and a specificity of 86%, obtained with IPPA polar tomograms(mild exercise defect) and a sensitivity of 86% and a specificityof 80% obtained with thallium (regionally decreased washout).With visual interpretation alone, a sensitivity of 83% and aspecificity of 71% was detected with IPPA (mild exercise defect)and 72% and 73%, respectively, with thallium (partial reversibility).The sensitivity of the exercise ECG alone was 62%. The results of this study imply that IPPA imaging could be arational, uncomplicated clinical method for non-invasive diagnosisof CAD. The diagnostic ability of IPPA is at least as good asthat of thallium, and it is possible to use them in succession.     

High-dose dipyridamole echocardiography test in coronary artery disease after heart transplantation

In order to evaluate the usefulness of high-dose dipyridamoleechocardiography test (DET) for the detection of coronary arterydisease (CAD) after heart transplant and for the assessmentof prognosis, 80 heart transplant patients underwent this testwithin 48 h of tile scheduled yearly coronary angiography. Coronary angiography showed normal coronary arteries in 55 patientsand CAD in 25, eight of whom had >50% luminal narrowing.Segmental hypokinesis on baseline echocardiography was presentin 27 patients, 19 of whom had CAD (sensitivity = 76%; specificity= 85%). DET was negative in all the patients with normal coronaryarteries (specificity 100%). Out of 25 patients with CAD, eighthad a positive DET and 17 a negative DET (sensitivity 32%),but DET was positive in seven of the eight patients with coronaryartery stenosis >50% (sensitivity 87%). During follow-up(9.8±4.5 months) seven cardiac events occurred in sevenpatients, all with CAD and wall motion hypokinesis (six on baselineechocardiogram and four after dipyridamole infusion). In our experience, DET does not seem adequate for the screeningof post-transplant CAD, but useful in identifying patients withsevere lesions (>50%). Wall motion abnormalities on baselineechocardiogram or after dipyridamole infusion might identifypatients who require closer surveillance. A longer experienceis needed to confirm these results.     

Detection of coronary artery disease by vasodilator thallium imaging of the heart with amyl nitrite inhalation: a pilot study.

Thallium imaging of the heart using dipyridamole-induced coronary arteriolar vasodilation has proven to be an effective means of detecting significant coronary stenosis. However, intravenous dipyridamole has not yet been made available for general use. We therefore examined the feasibility of substituting amyl nitrite inhalation as an arteriolar vasodilator prior to thallium imaging. Seventeen patients, all of whom had catheterization-proven coronary stenosis, inhaled amyl nitrite for 2-5 min. Thallium was injected after 45-60 s of inhalation. Completion of inhalation was followed immediately by planar imaging. Of 6 patients who inhaled amyl nitrite for at least 4 min, 5 had moderate or severe image defects on immediate scans which completely resolved on delayed scans. Only 3 of 11 who inhaled amyl nitrite for 2 min or less prior to scanning had similarly positive tests. Overall sensitivity for significant stenosis was 8 of 17 (47%). Inhalation was well tolerated with only one episode of angina and hypotension. We conclude that amyl nitrite inhalation for at least 4 min may offer an effective and readily available alternative to intravenous dipyridamole for vasodilator imaging of the heart.     

Comparison of optimised planar scintigraphy with SPECT thallium, exercise ECG and angiography in the detection of coronary artery disease

Background: Thallium SPECT has been shown to be more sensitive than planar imaging in the detection of coronary heart disease (CAD) in a number of reported series. Early (< 10 minutes) redistribution on planar imaging has been demonstrated in clinical studies and this may partly contribute to its lower sensitivity. Aim: To determine whether thallium SPECT is superior to planar scintigraphy (with the timing of imaging performed optimally so that it was commenced within five minutes of injection) in the detection of CAD. Methods: Planar and SPECT studies were performed in 44 patients with significant (>70% stenosis) CAD, seven patients with borderline stenoses (50–69%) and in 18 patients with no significant CAD. Results: The sensitivity of planar imaging was 66% which was higher than exercise ECG 54% (ns) but significantly lower than SPECT 86% (ρ<0.005). The specificity of planar thallium scintigraphy was 100% which was higher than SPECT (83%) and significantly higher than exercise ECG 72% (ρ<0.05). SPECT had a significantly higher sensitivity for LAD and single vessel disease than planar imaging and this was unrelated to a history of prior myocardial infarction. Conclusion: Even when planar imaging is timed optimally to minimise the impact of early redistribution, SPECT is more sensitive than either planar imaging or exercise ECG in the detection of CAD, but its specificity is lower.     

冠脉旁路移植术对冠心病三支病变患者近期生活质量的影响

目的 观察冠脉旁路移植术(CABC)对冠心病三支病变患者生活质量的影响.方法 将69例患者按其意愿分为两组,CABG组行CABG术治疗,药物组行标准药物治疗.两组在确诊后于治疗前及治疗后1 a分别填写西雅图心绞痛调查量表(SAQ),观察躯体活动受限程度(PL)、心绞痛稳定程度(AS)、心绞痛发作程度(AF)、治疗满意程度(TS)、疾病认识程度(DP)6个维度积分.结果 两组治疗前后整体生活质量有明显提高(P<0.01),CABG组术后各项指标改善程度较药物组显著(P<0.01);CABG组术前TS、DP低于药物组(P<0.05),术后和药物组无明显差异(P>0.05).结论 CABG术可明显改善冠心病三支病变患者生活质量;尽量减少手术创伤,减少术后并发症,术前及术后加强心理干预是进一步提高患者生活质量的重要措施.     

Arm exercise testing for coronary artery disease in patients with peripheral vascular disease

We evaluated 74 peripheral vascular disease (PVD) patients (54 men, age 61 +/- 7 years and 17 women, age 63 +/- 7 years) for potential coronary heart disease (CAD) using an arm exercise test (AET) protocol. All patients performed upright two-arm cranking using discontinuous stages of 2 minutes of exercise separated by 2 minutes of rest. Exercise intensity was increased by +100 or 200 kpm (kilopond meters) with each stage. ECG was monitored continuously and blood pressure and 12-lead ECG tracings were obtained at the end of each exercise stage. All patients reached an endpoint of subjective exhaustion. Men achieved 91 +/- 14% of age-predicted heart rate at 597 +/- 167 kpm, while women achieved 86 +/- 14% of age-predicted heart rate at 335 +/- 117 kpm. Ischemic ECG responses (+AET) defined as new or additional ST depression greater than 1.0 mm X 80 ms, occurred in 35 men (65%) and 7 women (42%). Coronary angiography was performed in a subset of 22 patients (15 males and 7 females). CAD (greater than 70% stenosis) was found in 11 of 12 men and 4 of 5 women who showed positive or strongly positive AET responses (overall predictive value for AET = 88%). We conclude that arm exercise stress testing is safely performed in PVD patients who cannot complete treadmill exercise. In this limited series of PVD patients, the predictive value of a +AET response for diagnosis of CAD is similar to established values for treadmill exercise.     

Hyperuricemia and severity of coronary artery disease in patients undergoing selective percutaneous coronary intervention

Background Hyperuricemia as an independent predictor for presence of coronary artery disease(CAD)has been studied insufficiently. In this study, we evaluated the predictive value of hyperuricemia for the severity of coronary artery disease. Methods A total of 683 patients undergoing elective percutaneous coronary intervention (PCI) were prospectively observed and were divided into two groups (hyperuricemic group, n = 216, and normouricemic group, n = 467). Hyperuricemia (HUA) was defined as an serum uric acid level 7 mg/dL in males and 6 mg/dL in females. Severe CAD was defined as triple-vessel disease or left main disease. Results One hundred and eighteen (55%) severe CAD occurred in the hyperuricemic group and 211(45%) in the normouricemic group (P = 0.02). The median uric acid levels of the severe CAD patients were significantly higher than secondary CAD (single vessel disease or two-vessel disease) patients (379 ± 111 vs 360 ± 105, P = 0.02). Multivariate logistic regression analysis, after adjusting for potential confounding factors, showed that HUA was an independent risk factor of coronary artery disease (odds radio = 1.63, 95% confidence interval, 1.02-2.61, P = 0.040). Moiety of in-hospital complications such as acute heart failure (17.6% vs. 6.2%, P 0.001), hypotension (3.8%, vs. 1.3%, P = 0.04), contrast induced nephropathy (CIN) (7.4% vs. 1.3%, P 0.001) after PCI, were significantly higher in hyperuricemic groups. Conclusions Hyperuricemia was an independent predictor for severe coronary artery disease (triple-vessel disease or left main disease).     

Reoperation for recurrent coronary artery disease – a ten year experience

The need for reoperation caused by recurrence of coronary artery disease is becoming increasingly common. Although reoperation is more difficult and time-consuming, with careful surgical technique it can be carried out with the same mortality as that described by many units for primary coronary artery bypass grafting (1.2 – 2.0%). In the 172 patients described here, who had coronary artery reoperations between 1981 and 1990, there were two in-hospital deaths (1.2%). There were three postoperative bleeds which required return to theatre. No patient suffered a postoperative neurological deficit or postoperative myocardial infarction. These reoperations comprised 6.9% of the 2497 coronary artery operations carried out in the same period. Follow-up disclosed eight late deaths, from five-62 months after operation; all survivors claim to be symptomatically improved. Consideration should be given to the potential problems of reoperation when carrying out primary myocardial revascularisation.     

Selection of the optimal stress test for the diagnosis of coronary artery disease

Objective—To compare the value and limitations of exercise testing, dipyridamole echocardiography, dobutamine-atropine echocardiography, and MIBI-SPECT (technetium-99m methoxyisobutyl nitrile single photon emission computed tomography) during dobutamine infusion in the diagnosis of coronary artery disease.
Design—The performance of these four tests was assessed in random order on a consecutive cohort of patients. The presence or absence of coronary artery disease was confirmed by coronary angiography.
Setting—Two tertiary care and university centres.
Patients—102 consecutive patients with chest pain and no previous history of coronary artery disease. Ten patients with left bundle branch block were excluded for further analysis of exercise testing and scintigraphy results.
Results—MIBI-SPECT was the most sensitive (87%) but the least specific test (70%). Exercise stress testing had a sensitivity of 66%, which increased to 80% when patients with inconclusive results were excluded. Dipyridamole and dobutamine echocardiography had similar sensitivity (81%, 78%) and specificity (94%, 88%). All four tests had similar accuracy and positive and negative predictive values. Agreement between the echocardiographic techniques was excellent (detection of coronary artery disease 87%, κ = 0.72; regional analysis 93%, κ = 0.72; diagnosis of the "culprit" vessel 95%, κ = 0.92), and it was good between echocardiographic techniques and MIBI-SPECT (diagnosis of the culprit vessel 90%, κ = 0.84 with dobutamine and 92%, κ = 0.85 with dipyridamole).
Conclusions—Exercise stress testing has a sensitivity comparable to other tests in patients capable of exercising and with no basal electrical abnormalities. The greatest sensitivity is offered by MIBI-SPECT and the greatest specificity is obtained with stress echocardiography. Redundant information is obtained with dipyridamole echocardiography, dobutamine echocardiography, and MIBI-SPECT.

Keywords: coronary artery disease;  dipyridamole;  dobutamine;  scintigraphy     

Time course and prognostic implications of QT interval in patients with coronary artery disease undergoing coronary bypass surgery

Course and Prognostic Implication of QT After CABG . Introduction: The aim of the present study was to determine the prognostic implication of preoperative QT interval in relation to overall death and sudden cardiac death after coronary bypass surgery and to investigate the course of QT interval after surgery. Methods and Results: Of 812 consecutive patients undergoing isolated off‐pump coronary surgery, 656 were retrospectively analyzed after excluding the 48 patients who were taking QT prolonging drugs and the 108 patients who had any of the following electrocardiographic findings: atrial fibrillation, pacemaker, QRS of >120 milliseconds, bundle branch block. QT intervals were corrected for heart rate (QTc) using Bazett's formula. Prolonged QTc was defined as QTc of ≥450 milliseconds in men (n = 144) and ≥470 milliseconds in women (n = 36). The 5‐year cumulative rate of sudden cardiac death in patients with prolonged QTc was 25% against 4% for those with normal QTc (P = 0.01). The risk‐adjusted hazard ratio (95% confidence interval) for the association between preoperative QTc and overall death was 1.47 (1.21–1.74) per 1‐SD increase in QTc; and 2.38 (1.50–3.45) for prolonged versus normal QT. For sudden cardiac death, the respective ratios were 1.63 (1.32–2.25) per 1‐SD increase in QTc; and 3.32 (2.14–4.23). QTc interval did not change during the first year after surgery, but increased significantly during the subsequent years. Patients with prolonged QTc before surgery had consistently longer QTc even after revascularization than those with normal QTc. Conclusion: Preoperative QT interval was an independent predictor of overall death and sudden cardiac death after isolated coronary bypass surgery. (J Cardiovasc Electrophysiol, Vol. 23, pp. 645–649, June 2012)     

老年冠心病患者冠状动脉病变程度与血管内皮功能的关系

目的探讨老年冠心病患者冠状动脉病变程度与血管内皮功能的关系。方法应用高分辨率彩色多普勒超声诊断仪对176例健康老年人(健康对照组)及161例老年冠心病患者(冠心病组)进行肱动脉血管内皮功能的超声检测,并对老年冠心病组患者冠状动脉病变支数与肱动脉血管内皮功能进行分析。结果反应性充血(reactive hyperemia,RH)后血管内径的变化率(flow-mediated diameter,FMD)及RH在老年冠心病组分别为6.05%及56.29%,而在健康对照组则分别为16.12%及127.23%,差异有显著性意义(P<0.001)。FMD在1支冠状动脉病变时为6.37%,在2支冠状动脉病变时下降为5.69%,而在3支冠状动脉病变时仅为3.94%;RH在1支冠状动脉病变时为62.19%,在2支冠状动脉病变时下降为53.45%,而在3支冠状动脉病变时仅为40.13%,差异有显著性意义(P<0.01)。结论老年冠心病组血管内皮功能较健康对照组明显减退。随着冠心病患者冠状动脉血管病变程度的增加,血管内皮功能进一步减退。血管内皮功能的减退在一定程度上可能反映了冠状动脉血管病变的严重程度。     

风心病患者瓣膜置换术前颈动脉超声检查的临床意义

目的探讨颈动脉粥样硬化与冠状动脉粥样硬化的相关性以及颈动脉内膜—中膜厚度(IMT)对风心病患者是否合并冠心病的预测价值。方法117例风心病患者根据冠状动脉造影结果分为冠心病组和对照组,用B超检测颈动脉病变情况。结果颈动脉IMT增厚和斑块检出率对冠心病预测的敏感性为81.82%(9/11),特异性为75.47%(80/106),阳性预测值为25.71%(9/35),阴性预测值为97.56%(80/82)。IMT异常与冠状动脉硬化程度积分呈显著正相关(r=0.55,P<0.01)。结论B超检测颈动脉粥样硬化对风心病患者是否合并冠心病具有预测价值。     

Coronary artery disease in patients undergoing cardiac surgery for non-coronary lesions in a tertiary care centre

Background

The objective of the present study was to determine the prevalence of coronary artery disease (CAD) in patients undergoing surgery for various valvular as well as non-valvular cardiac pathologies.

Methods

Patients with various valvular and non-valvular pathologies were selected. All patients with age ≥40 years and an indication for open heart surgery underwent pre-operative coronary angiogram and were included in the study.

Results

The mean age was 51.5 ± 9.02 years. 178 (59.3%) patients were males and 122 (40.7%) patients were females. Out of 300 patients, 270 (90%) patients had valvular heart disease (VHD) and 30 (10%) patients had non-valvular heart disease. Rheumatic heart disease (RHD), mitral valve prolapse (MVP), degenerative aortic valve disease (DAVD) and bicuspid aortic valve (BAV) was present in 161 (53.7%), 17 (5.7%), 60 (20%) and 32 (10.7%) patients respectively. Overall, 26 (8.7%) patients were found to have significant CAD. CAD was significantly more common in patients with VHD as compared to patients with other etiologies (1 patient, 3.3%, p < 0.05). In the valvular group, DAVD patients had maximum prevalence of CAD (14 patients, 23.4%, p < 0.05). In the group with CAD, the presence of variables such as age >60 years, male sex, typical angina, HT, dyslipidemia and smoking were significantly greater as compared to those with normal coronaries.

Conclusion

The overall prevalence of CAD among patients undergoing non-coronary cardiac surgery is 8.7%. Coronary artery disease is relatively uncommon in patients with rheumatic VHD (4.9%), while its prevalence is highest in DAVD (23.4%).     

Readmission and mortality in patients undergoing off-pump coronary artery bypass surgery with fast-track recovery protocol

The development of less invasive methods for myocardial revascularization such as “off-pump” cardiac surgery, and new methods of anesthesia and postoperative care protocols such as “fast-track recovery” (FTRC), have contributed to a significant reduction in postoperative intensive care unit (ICU) and hospital length of stay after cardiac surgical procedures. The objectives of this study were to identify perioperative risk factors of prolonged hospital stay, hospital mortality, and readmission rates in off-pump coronary artery bypass surgery (CABG) patients undergoing the FTRC protocol. Eighty consecutive patients undergoing off-pump coronary artery bypass surgery with FTRC protocol were included in the study. For the first purpose of this protocol, early extubation is defined as removal of the endotracheal tube within 6 h of arrival at the surgical ICU. The second purpose was to obtain a minimal length of stay in the ICU (<24 h) and hospital discharge within 5 days. We analyzed the influence of the preoperative, intraoperative, and postoperative variables on prolonged hospital stay, hospital mortality, and hospital readmission. Three patients died during hospitalization, giving a hospital mortality rate of 3.75%. The causes of hospital death were massive stroke and sepsis. Using multivariate logistic regression analysis, hypertension (P = 0.0185), postoperative stroke (P = 0.0001), and sternal infection (P = 0.0007) were identified as independent predictors of hospital mortality. Mean hospital length of stay was 4.23 ± 0.75 days. Univariate and multivariate logistic regression analysis revealed that postoperative blood use (P = 0.0095) was the major independent predictor of prolonged hospital stay. During the 30-day observation period, seven patients were readmitted. One of these patients died on postoperative day 45 from mediastinitis and sepsis. Multivariate logistic regression analysis identified age (P = 0.0033) and hypertension (P = 0.045) as independent predictors of hospital readmission. FTRC protocols can be performed safely in patients with off-pump CABG, and the mortality and readmission rates following this protocol were found to be within acceptable ranges.     

行经皮冠状动脉介入术老年人的冠状动脉病变特点

目的调查老年人行经皮冠状动脉介入术的冠心病患者冠状动脉病变特点。方法对比老年与中青年冠心病患者的临床特点、冠状动脉造影所见病变特点及经皮冠状动脉介入术疗效。结果老年组冠状动脉病变支数为(1.8±0.8)支;中青年组平均为(1.4±0.7)支。差异有统计学意义(P=0.024)。老年组单支病变18例,双支病变14例,3支病变10例;中青年组单支病变33例,双支病变9例,3支病变5例。老年组有心肌梗死史6例(14%),中青年组有心肌梗死史18例(38%),差异有统计学意义(P<0.02)。术后6个月电话随访生存率为99.2%。问卷随访(21±9)个月,其中出现心血管不良事件4例,老年组1例,中青年组3例;6例经皮冠状动脉介入术不满意者,术后症状未改善,其中老年组2例,中青年组4例(P>0.05)。结论老年冠心病患者冠状动脉病变程度较重,多支血管病变多见。应选择合适病例进行经皮冠状动脉介入术治疗。     

冠状动脉主干重度狭窄搭桥术麻醉处理486例总结

目的:探讨冠心病冠状动脉主干重度狭窄患者,行搭桥术临床特点及围术期治疗措施。方法:我们对2001年1月至2010年10月,486例冠状动脉主干重度狭窄行搭桥术患者的麻醉及围术期治疗进行回顾性分析。结果:442例行非体外循环下冠状动脉搭桥术(OPCABG)。28例在体外循环下行冠状动脉搭桥术(CABG)。16例患者在OPCABG过程中,由于发生严重心肌缺血、心动过速及低血压,改为体外循环下完成手术。113例放置主动脉内球囊反搏(IABP),包括术前、麻醉前放置8例,麻醉后及术中放置78例,术后放置27例。死亡9例,发生在术后72 h内。结论:冠心病冠状动脉主干重度狭窄患者,围术期需要维持心率、血压平稳、合理的血管扩张药和正性肌力药物选用,IABP的积极使用,完备的体外循环和急救药的准备,防治患者围术期冠状动脉痉挛和心肌梗死。     

Intraoperative epicardial coronary artery imaging: rationale,methods, and applications

Epicardial coronary imaging using high frequency (7-12 MHz) ultrasound probes could aid the surgeon performing coronary artery bypass procedures by localizing the coronary artery segments underneath epicardial fat, identifying the site of coronary stenosis to be bypassed, evaluating the integrity of distal coronary artery, assessing the efficacy of anastomosis, and detecting anastomotic complications. While an ideal coronary imaging probe is yet to be developed, early clinical experience with vascular imaging probes applied on the coronary vessels suggests that epicardial coronary artery imaging could enhance the optimum performance of coronary interventions. Fabrication of a flexible high frequency probe that could be applied not only on the arteries on the anterior surface of the heart but also on the lateral and posterior surfaces could facilitate development of newer surgical procedures as well.     

Comparison of angioplasty and bypass surgery in multivessel coronary artery disease

The role of coronary angioplasty in the treatment of patient with multivessel coronary artery disease has not been fully established. We compared immediate and 1-year follow-up results in 60 patients undergoing coronary angioplasty for multivessel coronary disease in 1982 with 41 patients anatomically suitable for angioplasty but who underwent elective coronary bypass surgery during the same time period. Baseline variables were similar in both groups except for number of vessels diseased which was higher in the surgical group. Angioplasty was initially successful in 70% of cases. There were no deaths. Mean initial hospital days were lower in the angioplasty group. At follow-up there were no significant differences in survival, functional class, occurrence of subsequent myocardial infarction or use of cardiac medications. However, 33% of the successfully dilated patients required either repeat dilatation or subsequent bypass surgery because of restenosis or inadequate initial revascularization. The statistical power of the study was limited due to the small sample sizes. While demonstrating that angioplasty can be successfully performed in patients with multivessel disease, definitive conclusions about the comparability of the two treatments are hampered by possible selection bias and small patient numbers. This issue could be better addressed by a multicenter prospective randomized trial.