Aspirin, heparin, or both to treat acute unstable angina

We tested the usefulness of aspirin (325 mg twice daily), heparin (1000 units per hour by intravenous infusion), and a combination of the two in the early management of acute unstable angina pectoris in a double-blind, randomized, placebo-controlled trial involving 479 patients. The patients entered the study as soon as possible after hospital admission (at a mean [+/- SD] of 7.9 +/- 8.0 hours after the last episode of pain), and the study was ended after 6 +/- 3 days, when definitive therapy had been selected. Major end points--refractory angina, myocardial infarction, and death--occurred in 23, 12, and 1.7 percent of the 118 patients receiving placebo, respectively. Heparin was associated with a decrease in the occurrence of refractory angina (P = 0.002). The incidence of myocardial infarction was significantly reduced in the groups receiving aspirin (3 percent; P = 0.01), heparin (0.8 percent; P less than 0.001), and aspirin plus heparin (1.6 percent, P = 0.003), and no deaths occurred in these groups. There were too few deaths overall to permit evaluation of the effect of treatment on this end point. The combination of aspirin and heparin had no greater protective effect than heparin alone but was associated with slightly more serious bleeding (3.3 vs. 1.7 percent). We conclude that in the acute phase of unstable angina, either aspirin or heparin treatment is associated with a reduced incidence of myocardial infarction, and there is a trend favoring heparin over aspirin. Heparin treatment is also associated with a reduced incidence of refractory angina.     

Ten-year survival after coronary bypass surgery for unstable angina

We have assessed the long-term results of coronary bypass surgery performed for unstable angina in 1282 patients from 1970 to 1982. The operative mortality was 1.8 per cent; in the first 4 years it was 2.5 per cent, and in the last 8 1/2 years it was 1.7 per cent. Using actuarial techniques, we determined that the 5-year and 10-year survival rates (mean +/- S.E.) were 92 +/- 1 per cent and 83 +/- 2 per cent, respectively, for the whole group. For patients with "normal" left ventricular function, they were 92 +/- 2 per cent and 86 +/- 3 per cent, and for patients with "abnormal" left ventricular function 91 +/- 2 per cent and 79 +/- 4 per cent (P = 0.14). No significant differences were observed in the long-term survival for any of the three clinical subgroups of patients with unstable angina--angina at rest, angina after recovery from acute myocardial infarction, and progressive angina of recent onset (P = 0.49). The reoperation rates at 5 and 10 years were 6 +/- per cent and 17 +/- 3 per cent. Currently, 61 per cent of the survivors have no angina; angina occurs on severe exertion in 20 per cent, on ordinary exertion in 14 per cent, and on mild exertion in 5 per cent. We conclude that coronary bypass surgery is an effective form of therapy (for up to 10 years) in patients with unstable angina.     

Atherosclerosis and unstable angina in Bernard-Soulier syndrome.

Platelets and von Willebrand factor play pathogenetic roles in atherosclerosis and acute coronary artery ischemic syndromes. Patients with Bernard-Soulier Syndrome are deficient in several platelet membrane glycoproteins, including glycoprotein Ib (GpIb). Glycoprotein Ib is the primary platelet receptor for von Willebrand factor and plays a critical role in the initiation of thrombus formation. Glycoprotein Ib, but also GpIIb/IIIa, mediates the adhesion of platelets to damaged endothelium, particularly at the high shear stresses found in small or diseased arteries. A patient with Bernard-Soulier syndrome is described who developed coronary artery atherosclerosis and unstable angina requiring coronary artery bypass grafting. The implications of this experiment in nature on the contribution of platelets and platelet GpIb and GpIIb/IIIa receptors to the development of atherosclerosis and unstable angina are discussed.     

Actuality in the treatment of unstable angina pectoris

In an attempt to relieve ischaemic symptoms and to prevent progression to myocardial infarction, coronary angioplasty was attempted in 236 multivessel coronary heart disease patients with unstable angina, refractory to medical treatment including oral Ca2+ antagonists, beta blockers and nitroglycerin drugs. Unstable angina was defined as ischaemic chest pain at rest lasting for at least 20 min, accompanied by reversible ST-T changes. The initial angioplasty success rate was 87% (205/236 cases). Vessel occlusion necessitating urgent bypass surgery occurred in five patients (2.1%). There was evidence of myocardial infarction in eight patients (3.4%). There were seven deaths (2.9%) related to the procedure. 191 of the 205 successfully dilated patients were followed up for 14 months on the average. Late mortality occurred in 4.2% (8/191), late nonfatal infarction in 2.6%, 127 patients remained asymptomatic and 11 were considered to be disabling angina (New York Heart Association classification III or IV). Recurrent angina rate with progression in ischaemic disease (restenosis and native vessel stenosis) occurred in 30%. For this reason, repeated angioplasty and elective bypass surgery were performed in 48 and 14 cases, respectively. These results support the growing evidence that angioplasty as an emergency procedure in multivessel disease patients with unstable angina pectoris refractory to intensive medical treatment can restore coronary blood flow with an acceptable risk and a good initial and short-term success rate.     

The prognostic value of serum troponin T in unstable angina.

BACKGROUND. Cardiac troponin T is a regulatory contractile protein not normally found in blood. Its detection in the circulation has been shown to be a sensitive and specific marker for myocardial cell damage. We used a newly developed enzyme immunoassay for troponin T to determine whether its presence in the serum of patients with unstable angina was a prognostic indicator. METHODS. We screened 109 patients with unstable angina (25 with accelerated or subacute angina and 84 with acute angina at rest) for serum creatine kinase activity, creatine kinase isoenzyme MB activity, and troponin T every eight hours for two days after admission to the hospital. The outcomes of interest during the hospitalization were death and myocardial infarction. RESULTS. Troponin T was detected (range, 0.20 to 3.64 micrograms per liter; mean, 0.78; median, 0.50) in the serum of 33 of the 84 patients (39 percent) with acute angina at rest. Only three of these patients had elevated creatine kinase MB activity (two were positive for troponin T, and one was negative). Of the 33 patients who were positive for troponin T, 10 (30 percent) had myocardial infarction (3 after coronary-artery bypass surgery), and 5 of these died during hospitalization. In contrast, only 1 of the 51 patients with angina at rest who were negative for troponin T had an acute myocardial infarction (P less than 0.001), and this patient died (P = 0.03). Thus, 10 of the 11 patients with myocardial infarctions had detectable levels of troponin T; only 1 had elevated creatine kinase MB activity. Troponin T was not detected in any of the 25 patients with accelerated or subacute angina, and none of these patients died. CONCLUSIONS. Cardiac troponin T in serum appears to be a more sensitive indicator of myocardial-cell injury than serum creatine kinase MB activity, and its detection in the circulation may be a useful prognostic indicator in patients with unstable angina.     

经皮冠状动脉介入术对不稳定型心绞痛患者QT离散度的影响

目的 探讨经皮冠状动脉介入术（PCI）治疗不稳定型心绞痛（UA）对QT离散度（QTd）的影响。方法 58例经皮冠状动脉介入术治疗不稳定型心绞痛及54例对照组在术前24h，术后6、24h和1周分别同步记录12导联心电图，测量QTd及QTcd。结果 治疗组支架置入术后QTd、QTcd早期（6h）即有明显改善，对照组冠造前后QTd、QTcd无显著改善。结论 经皮冠状动脉介入术可显著改善不稳定型心绞痛患者术后的QT离散度。     

Emergency coronary angioplasty in refractory unstable angina

We performed percutaneous transluminal coronary angioplasty as an emergency procedure in 60 patients with unstable angina pectoris that was refractory to treatment with maximally tolerated doses of beta-blockers, calcium antagonists, and intravenous nitroglycerin. The initial success rate for angioplasty was 93 per cent (56 patients). There were no deaths related to the procedure, although total occlusion occurred in four patients. Despite emergency bypass grafting, all four sustained a myocardial infarction. All the patients were followed for at least six months. Late cardiac death occurred in one patient, whereas eight had recurrent angina pectoris. There was no progression to myocardial infarction. The restenosis rate was 28 per cent (13 of 46) in the patients with initially successful coronary angioplasty who had repeat angiography. Improved cardiac functional status after sustained successful coronary angioplasty was demonstrated by an almost normal capacity on bicycle exercise testing and the absence of ischemia during thallium isotope studies in 80 per cent. We conclude that emergency percutaneous transluminal coronary angioplasty may be useful for the treatment of selected patients with unstable angina pectoris who are unresponsive to intensive pharmacologic treatment.     

Denial and medical outcome in unstable angina

Denial may be adaptive during hospitalization for acute coronary disease. We studied the impact of denial in 48 patients referred to a tertiary care center for treatment of unstable angina. Using the Hackett-Cassem Denial Scale, we divided the group into 25 high deniers and 23 low deniers. The two groups were comparable in baseline demographic and social data, coronary risk factors, cardiac history, medical treatment, vital signs, and cardiac catheterization results (number of diseased vessels and ejection fraction). Compared to low deniers, high deniers had half as many episodes of angina during hospitalization (1.3 vs. 2.5; p less than 0.03, t = 2.2, df = 46) and were more likely to reach medical stabilization, i.e., pain free for 36 hr (92% vs. 65%, p less than 0.03, Fisher exact probability test). Intravenous nitroglycerin drips were also required less often in high deniers (32% vs. 78%, p = 0.002, Fisher exact). Two myocardial infarctions and one death occurred, all in low deniers. We conclude that denial independently predicts better medical outcome during acute hospitalization for unstable angina.     

高龄不稳定心绞痛患者两种治疗方法的预后比较

目的评价急诊冠状动脉介入（PCI）和单纯药物治疗高龄不稳定型心绞痛（UA）患者的近期与远期疗效。 方法经冠状动脉造影证实存在冠状动脉病变、年龄≥75岁的UA患者191例分别行PCI和单纯药物治疗（药物治疗组）,两组的平均年龄、心绞痛类型、伴发疾病差异均无统计学意义,PCI组的双支冠状动脉病变较药物治疗组多,临床观察分析两组的近期和远期疗效。 结果从近期疗效看,PCI组无猝死和院内急性心肌梗死的发生,但药物治疗组有6例院内猝死发生,差异有统计学意义（P〈0．05）。从远期疗效看,药物治疗组有8例心肌梗死、27例心因性死亡和19例再次PCI或冠状动脉旁路移植手术（CABG）者,而PCI组分别为2、8和8例,两组比较差异均有统计学意义（χ^2=15．7304、6．8385,P〈0．001、〈0．05）：PCI组有23例心绞痛复发者,药物治疗组有28例,两组之间差异无统计学意义（χ^2=1．6766,P〉0．05）。药物治疗组左心功能不全和双支冠状动脉病变患者出现心因性死亡者、高脂血症患者心绞痛复发及糖尿病患者、双支冠状动脉病变患者需再次PCI或CABG者均多于PCI组（均P〈0．05）;3支冠状动脉病变者再次PCI或CABG者少于PCI组（P〈0．05）。 结论PCI可明显改善高龄不稳定心绞痛患者的近期和远期疗效。     

Ultrastructural studies of unstable angina in living man

Nineteen patients with refractory unstable angina who were undergoing aortocoronary bypass were studied to assess the extent of platelet aggregation present in the microvasculature. Ultrastructural findings on the morphology of cardiac muscle and microvasculature were correlated with the findings on coronary angiograms and thallium scans. There were no significant correlations. The presence of platelet aggregates was identified in four biopsies, two of which had thrombus by angiographic criteria. Biopsy in areas with thallium defects revealed an increased prevalence of white blood cells without acute myocardial infarction. This study confirms the presence of platelet aggregates in patients with unstable angina, albeit at a reduced frequency when compared with autopsy studies.     

Coronary angioscopy in patients with unstable angina pectoris

To visualize intracoronary lesions in patients with different clinical expressions of coronary disease, we performed coronary angioscopy during coronary-artery bypass surgery in 10 patients with unstable angina and 10 patients with stable coronary disease. We examined a total of 32 vessels, using flexible fiberoptic angioscopes. Twenty-two vessels had no acute intimal lesion; three had complex plaques, six had thrombi, and one had both. Coronary angiography correctly identified the absence of complex plaque and thrombus in 22 vessels, but it detected only one of four complex plaques and one of seven thrombi. On angioscopy, none of the 17 arteries in the patients with stable coronary disease had either a complex plaque or thrombus. In the "offending" arteries of the patients with unstable angina, all three patients with accelerated angina had complex plaques and all seven with angina at rest had thrombi. We conclude that angioscopy frequently reveals complex plaques or thrombi not detected by coronary angiography. Our observations suggest that anginal syndromes that are refractory to medical treatment can be caused by unstable pathologic processes in the intima. Ulceration of plaques may increase the frequency and severity of effort angina, and the subsequent development of partially occlusive thrombi may cause unstable rest angina.     

Denial predicts favorable outcome in unstable angina pectoris

Denial may be prognostically favorable in patients with acute myocardial infarction. We analyzed the significance of denial in 26 patients referred to a tertiary care center for advanced therapy of unstable angina. Group A comprised 14 patients characterized as deniers on the Hackett--Cassem Denial Scale. Group B comprised 12 nondeniers. There were no differences between groups in multiple baseline social and demographic characteristics, cardiac history, or risk factors. Similarly, there were no differences in the number of diseased vessels or left ventricular function in those patients catheterized (11 Group A patients, 9 Group B patients). Group B, however, had a longer hospitalization until medically stabilized (pain-free for 36 hr) than Group A (5.9 +/- 3.6 days vs. 3.0 +/- 1.6 days; p = 0.02) despite similar treatment regimens. There were no significant differences in incidence of myocardial infarction or need for surgery. There were two deaths--both in Group B patients. We conclude that denial independently predicts rapid medical stabilization in unstable angina patients. Whether it predicts better longterm outcome requires further study.