Percutaneous transluminal coronary angioplasty of one vessel for refractory unstable angina pectoris: efficacy in single and multivessel disease

Coronary Angioplasty in Patients with Unstable Angina, with Special Reference to Preceding Treatment with Antithrombin III and Heparin

Seventy-nine patients undergoing percutane ous transluminal coronary angioplasty (PTCA) for unsta ble angina were analyzed with respect to preceding an tithrombin treatment; group I comprised patients (n = 26) without antecedent antithrombin therapy; group II, pa tients (n = 30) with heparin infusion for ≥24 h, and group III patients (n = 23) with ongoing heparin infusion and given antithrombin III concentrate immediately before the procedure because of plasma antithrombin III <85%. Immediate results were 89% (70 of 79) angiographic suc cess, five (6%) subacute occlusions (two subsequent non-Q wave infarctions), no emergency coronary artery bypass grafting (CABG), and no immediate mortality. There were no differences between the groups. From dis charge to 4 months, one patient died, one had a nonfatal infarction, and 24 (30%) had repeated PTCA or CABG. The cumulative 4-month event rate was 11 of 26 (42%) in group I, 10 of 30 (33%) in group II, and 7 of 23 (30%) in group III (NS). During PTCA, heparin bolus administra tion was guided by activated clotting time (ACT), aiming at>300 s. Baseline ACT was significantly less in patients not treated with heparin (129 ± 34 s in group I vs. 179 ± 38 and 162 ± 29 s in groups II and III, respectively; p < 0.05), but during the procedure, patients from all groups required the same amount of heparin (13,900 ± 4,800, 13,000 ± 6,800, and 13,000 ± 5,700 IU, respectively; NS) to reach similar maximum ACT levels (334 ± 36, 312 ± 32, and 319 ± 44 s, respectively; NS). Patients receiving warfarin ( n = 8) responded with a higher ACT (456 ± 110 s; p < 0.05) on lower doses of heparin (10,000 ± 3,800 IU). In conclusion, patients with unstable angina receiv ing individualized antithrombotic therapy can be success fully treated with PTCA, with an acute complication rate and long-term results comparable with those expected in patients undergoing elective procedures. The value of an tithrombin III substitution must be evaluated in random ized trials. Preprocedural heparin infusion does not re duce the need of extra heparin during the procedure. Key Words: Antithrombin III—Heparin—PTCA (percutane ous transluminal coronary angioplasty)—Unstable angina pectoris.

Visualized plaque debris as a cause of distal embolization after percutaneous coronary intervention in patient with unstable angina

Procedural complications of percutaneous transluminal coronary angioplasty for unstable angina are higher than for stable angina. We report a case in which coronary angioscopy proved the dislodgment of a large plaque fragment after Cutting Balloon angioplasty and confirmed our suspicion that plaque fragmentation can cause distal embolization.

Management of high-risk subsets in unstable angina

This article focuses on the optimal treatment of postinfarction, refractory, or recurrent angina based on the results of recent clinical trials. Many of our recommendations hold true for the general management of unstable angina, but special considerations for the high-risk subsets are emphasized. Specifically, we discuss acute medical management and suggest that an early aggressive strategy that leads to early coronary angiography with the goal of revascularization when feasible best serves this subset. A special emphasis on the emerging role of glycoprotein IIb-IIIa antagonists is made because the important role of platelets in coronary thrombosis has dominated recent views on the pathophysiology of unstable angina.

Percutaneous transluminal coronary angioplasty in refractory unstable angina pectoris: are new devices useful?

This study was undertaken to assess if the introduction of new angioplasty devices (autoperfusion balloon catheters, stent and atherectomy) could ameliorate early and late results of prompt percutaneous transluminal coronary angioplasty (PTCA) in patients with refractory unstable angina. From January 1993 to June 1995, 59 of 278 patients (14 female, 45 male; mean age: 61 +/- 10 years; range: 38-78) admitted to our Coronary Care Unit with the diagnosis of unstable angina had more than one episode of chest pain at rest with dynamic electrocardiographic ST-T changes and without signs of cardiac necrosis while on medical therapy including oxygen, aspirin, heparin, nitroglycerin and either a beta-blocker or a calcium-antagonist. Coronary angiography was performed within 48 h from the last ischemic attack and a culprilesion technically suitable for PTCA was identified. PTCA was performed in 73 lesions. Elective stent implantation was considered for 16 type B or C lesions in 14 patients. The procedure was initially successful in 52/59 patients (88%), uncomplicated unsuccessful in 4/59 (7%) and complicated in 3/59 (5%). Elective stent insertions were all successful (16/16, 100%). All successfully treated patients were followed up for a mean of 12 +/- 7 months (range: 6-27): 2/52 patients (3.8%) suffered from non-transmural myocardial infarction, 14/52 (26.9%) had a recurrence of angina and 2/52 (3.8%), asymptomatic, had a positive stress test. We conclude that prompt PTCA in refractory unstable angina using 1990s 'state of the art' equipment compares favorably to previous study and that stent delivery might become the elective treatment of complex lesions in this subset of patients.

Effect of the increasing use of coronary angioplasty on outcome at one year in patients with unstable angina

OBJECTIVE

To determine whether the increasing use of percutaneous transluminal angioplasty in patients with unstable angina has reduced the need for bypass surgery and whether this change in the choice of treatment affected the outcome at one year in patients with unstable angina who were admitted to hospital in two different periods of time.

DESIGN

Retrospective analysis of consecutive patients with unstable angina (angina at rest with ST-T changes during pain) who underwent coronary arteriography in two different periods of time.

PATIENTS

158 patients were admitted to hospital between January 1988 and June 1989 (group 1) and 140 patients admitted between January 1992 and June 1993 (group 2).

RESULTS

Coronary angioplasty procedures nearly doubled from 29% in group 1 to 56% in group 2 whereas bypass surgery decreased from 36% in group 1 to 23% in group 2 (P < 0.01). Coronary angioplasty increased and bypass surgery decreased in patients with one vessel disease (P < 0.01), two vessel disease (P < 0.05), and three vessel disease (P < 0.01). Coronary angioplasty also increased and bypass surgery decreased in refractory angina and in patients with ejection fraction < 0.50 (both P < 0.05). At 1-year follow up, 14 patients in group 1 (9%) and 10 in group 2 (7%) either died or had myocardial infarction (P = NS). Revascularisation procedures were needed in 16 group 1 patients (10%) and 27 group 2 patients (19%, P < 0.05).

CONCLUSIONS

Coronary angioplasty became more widely used in patients with unstable angina. This reduced the need for bypass surgery in patients with multivessel disease, refractory angina, and depressed left ventricular function. This change in treatment did not affect 1-year mortality or the myocardial infarction rate. More patients in the more recent group in which angioplasty was the preferred treatment required a further revascularisation procedure than in the earlier group in which bypass grafting was more often used as the initial treatment.

Outcome of percutaneous transluminal coronary angioplasty in subsets of unstable angina pectoris

OBJECTIVES

The purpose of this study was to characterize the outcome of coronary angioplasty according to the various presentations of unstable angina pectoris.

BACKGROUND

Although unstable angina is a mosaic of clinical manifestations, a comprehensive analysis of short- and long-term outcome of coronary angioplasty in subsets of unstable angina is not available.

METHODS

Data from 15 clinical centers for the 857 patients with unstable angina in the 1985-1986 National Heart, Lung, and Blood Institute percutaneous transluminal coronary angioplasty registry were analyzed. Five-year follow-up was available in > 96.5%. Patients were first classified as those with (679 [79%]) or without (178 [21%]) rest angina. Patients were also allocated to five mutually exclusive categories of decreasing unstable angina severity: postinfarction angina, acute coronary insufficiency, plain rest angina, accelerating angina and new onset angina.

RESULTS

The group with rest angina had more older patients (p < 0.01) and women (p < 0.001), and a greater proportion had a previous myocardial infarction (p < 0.001) and a left ventricular ejection fraction < or = 50% (p < 0.01) than did the group without rest angina. Angiographic characteristics were nearly the same, whereas procedural characteristics and outcome were the same for both categories. At 5-year follow-up, there was a higher crude mortality rate in patients with than without rest angina (p < 0.05). Resolution into five subsets yielded additional information. Women were more represented only in the acute coronary insufficiency and plain rest angina subsets (p < 0.001). Patients with angina after myocardial infarction had the second shortest history of angina (p < 0.001), the highest percent of smokers (p < 0.01) and, with those with acute coronary insufficiency, the highest incidence of congestive heart failure (p < 0.05) and an ejection fraction < or = 50% (p < 0.001). They had the highest percent of totally occluded arteries, coronary thrombus and collateral blood flow received but also the lowest rate of severe stenoses (p < 0.001 for all). Patients with new onset angina had the highest prevalence of single-vessel disease (p < 0.05), critical and complex stenoses (p < 0.001) and no coronary angioplasty-related deaths. The crude 5-year mortality rate was higher for both postinfarction and acute insufficiency groups (p < 0.05) than for the other subsets. After adjustments for risk factors, no significant differences in adverse event rates remained among the different unstable angina subgroups.

CONCLUSIONS

Analysis of the diverse clinical presentations of unstable angina supports underlying pathogenetic differences. Coronary angioplasty is safe and effective in all subsets of unstable angina. Long-term survival is good in general but is related to the baseline status of left ventricular function.

Aggressive clinical pattern of angina at restenosis following coronary angioplasty in unstable angina

The frequency, clinical pattern, and timing of recurrent angina following successful single-lesion percutaneous transluminal coronary angioplasty (PTCA) was assessed in a consecutive group of 104 patients with stable angina and in 85 with unstable angina. In addition, the relationship between lesion morphology and angiographic features and the pattern of recurrent angina was determined. Restenosis, defined as recurrence of symptoms with > 50% stenosis at the site of PTCA, occurred in 25 (24%) of the stable group and in 23 (27%) of the unstable group (p = NS). The pattern of angina at repeat presentation was aggressive in nature in 8% of the stable group and in 48% of the unstable group (p = 0.002). The time interval between the recurrence of symptoms and repeat coronary angiogram or PTCA was longer in the nonaggressive group than in the aggressive group, 16 +/- 12.1 and 5 +/- 6.8 weeks, respectively (p < 0.003). The key factors predicting the recurrent angina pattern identified by multiple logistic regression analysis were the angina status pre-PTCA (p = 0.001) and the presence of double-vessel disease (p = 0.01). An aggressive pattern of angina at the time of restenosis is frequent in patients with unstable angina at the time of PTCA, and close post-PTCA surveillance is necessary in these patients.

Salvage angioplasty: an alternative to high risk surgery for unstable angina?

This prospective, Human Subjects Committee and Ethics Committee approved investigation was performed to determine if coronary angioplasty (PTCA) might be a reasonable alternative revascularization method for unstable angina patients thought to be at high risk for operative (CABG) mortality. Between March 1990 and October 1991, thirty-four consecutive patients with medically refractory rest angina were deamed to have high risk of surgical mortality and underwent PTCA without surgical backup. Predicted operative mortality was calculated for each patient based upon the VA Surgical Risk Assessment model. Angioplasty of 52 vessels was attempted. Reduction in lumenal narrowing to < 50% and improved angiographic flow was obtained in 47 vessels. There were four complicating infarctions. One death occurred in the lab, and three patients with unsuccessful angioplasty died within 30 days of pump failure. Relief of angina occurred in 30/34. Thirty patients were discharged home. In follow-up from 1 to 12 months, there have been 2 late sudden deaths at 4 months and 9 months, 1 death from lung cancer; 4 patients have stable exertional angina; 2 are awaiting heart transplant but are pain free, and one patient who had PTCA during cardiogenic shock from acute myocardial infarction had elective coronary artery bypass surgery. There have been no late myocardial infarctions. The observed angioplasty 30-day mortality of 11.8% (95% confidence limit 1% to 22.6%) compares favorably with the predicted operative mortality of 23.8% for this group. This prospective but non-randomized series supports the concept that balloon angioplasty may be a reasonable alternative to surgical intervention in some patients with unstable angina and high risk for surgery. A prospective randomized trial is warranted.

Percutaneous transluminal coronary angioplasty for unstable angina

Coronary angioplasty is an effective treatment for patients with angina at rest, either refractory or initially stabilized but returning despite pharmacologic treatment, and with early postinfarction angina. The procedure has a high initial success rate, but there is an increased risk of major complications resulting from a higher incidence of acute closure, which may be related to preexisting thrombus. Resolution of this problem may be achieved by the use of more potent antiplatelet treatment, pretreatment with thrombolytic agents, or treatment that can be applied locally (e.g., laser energy, atherectomy) at the site of the unstable plaque. Results in this study have been obtained from selected groups of patients: those with predominantly single-vessel disease and well-preserved left ventricular function. It remains to be determined whether the same benefits can be achieved in patients with multivessel disease or in those who have severely reduced left ventricular function.

Short and long term outcome of percutaneous transluminal coronary angioplasty in unstable versus stable angina pectoris: a report of the 1985-1986 NHLBI PTCA Registry

In a cohort of 1,720 consecutive patients from the National Heart, Lung, and Blood Institute, Percutaneous Transluminal Coronary Angioplasty (PTCA) Registry (August 1985-May 1986), we compared 768 patients (45%) with stable angina and 952 patients (55%) with unstable angina pectoris. Unstable angina patients exhibited at least one of the following characteristics: new onset angina, rapidly progressing angina, angina at rest, angina refractory to medication, variant angina, acute coronary insufficiency, or angina recurring shortly after an acute myocardial infarct. The distribution of single- and multi-vessel disease was similar among stable and unstable angina patients; multi-vessel disease predominated. Average severity of stenosis and incidence of tubular and diffuse stenosis morphology were higher among patients with unstable angina (both p less than 0.001). Patient success rates were similar in stable and unstable patients. However, on a per lesion basis, overall angiographic success rate and average reduction of severity of stenosis in successfully dilated lesions were significantly higher among patients with unstable angina (both p less than 0.001). Incidence of major patient complications (p less than 0.01) and of emergency coronary bypass surgery (p less than 0.05) were also higher in patients with unstable angina but consistent with their more precarious clinical condition and stenosis morphology. During a two year follow-up, the cumulative distributions of death, myocardial infarct, repeat PTCA, and coronary bypass surgery were not significantly different in patients with stable angina compared to patients with unstable angina. Comparison of the current PTCA Registry cohort with the cases reported in the 1979-1982 Registry revealed a 19% higher success rate for both stable and unstable angina patients. Major complication rates decreased between time periods for stable but not for unstable angina patients. Incidence of emergency bypass surgery decreased more for stable than for unstable angina patients. Coronary angioplasty is indicated in properly selected patients with unstable angina and both single- and multi-vessel coronary disease.

Percutaneous coronary angioplasty in 1,001 multivessel coronary disease patients: an analysis of different patient subsets

The prospectively collected data of 1,001 multivessel coronary disease patients who underwent percutaneous transluminal angioplasty (PTCA) was analyzed after categorization into single vessel angioplasty (SVA; group I) and multiple vessel angioplasty (MVA; group II) PTCA groups, which were each compartmentalized into "simple" (group A) and "complex" (group B) cohorts. Patients were assigned to the SVA or MVA group according to the physician's pre-PTCA assessment of how many lesions would be attempted (intention to treat) and not the number of lesions actually attempted. A "simple" patient was more likely than a "complex" patient to be clinically improved after PTCA whether or not the patient had a single dilatation (90% vs 78%; P less than 0.05) or multiple dilatations (97% vs 94%; P<0.05). Similarly, a lesion(s) was more likely to be successfully dilated in the "simple" than in the "complex" group (SVA: 90% vs 82%, P less than 0.05; MVA: 97% vs 91%, P<0.05). In addition, occluded vessels in the MVA group were more likely to be recanalized than in the SVA group (73% vs 44%, P less than 0.05). Group I-A patients had a significantly increased (10%) incidence of emergency bypass surgery. Follow-up, at 84 months, showed that "simple" cohorts had a better survival than the "complex" cohorts (MVA: 95% vs 71%, P less than 0.05; SVA: 90% vs 72%, P less than 0.05); and, nearly two thirds of all successful PTCA patients were angina free.(ABSTRACT TRUNCATED AT 250 WORDS)

Unstable angina pectoris

The pathophysiology of unstable angina has been better elucidated in the past five years and has led to more rational therapy. Coronary arteries in patients with unstable angina have atherosclerotic plaques which are often complex and are the site of platelet activation and fibrin deposition. Nitrates, one of the oldest therapies, are efficacious and act not only by dilating coronary vessels but by reducing preload and afterload. Beta blockers have a salutary effect by decreasing myocardial oxygen demand. Calcium channel blockers attenuate smooth muscle contraction and thereby act to decrease coronary artery spasm. Beta blockers and calcium channel blockers are equally efficacious in unstable angina. The antiplatelet agent, aspirin, has been shown to reduce fatal or non-fatal myocardial infarction and probably overall mortality. The use of heparin acutely for unstable angina has been demonstrated to decrease refractory angina and myocardial infarction, and acutely is probably better than aspirin. For patients with reduced ejection fractions (0.30-0.49), a prospective randomized trial has shown that coronary artery bypass graft surgery offers an improved three-year survival compared with medical therapy; however, surgery does not prevent myocardial infarction. Percutaneous transluminal coronary angioplasty may be a reasonable therapeutic alternative for some patients with single-vessel disease who are refractory to medical therapy but there are as yet no controlled trials of this question. To date a clinical benefit from thrombolytic therapy has not been demonstrated.

Percutaneous transluminal coronary angioplasty for rest angina pectoris requiring intravenous nitroglycerin and intraaortic balloon counterpulsation

In selected patients with medically refractory rest angina, percutaneous transluminal coronary angioplasty (PTCA) might be a reasonable alternative to coronary artery bypass graft surgery. Between January 1987 and November 1989, 1 operator at a Veterans Administration center performed PTCA on 73 vessels in 56 patients with rest angina of sufficient severity to require intravenous nitroglycerin in all 56 and intraaortic balloon counter-pulsation (IABP) in 18. Of the 56 patients, 17 (30%) had 1-vessel disease, 14 (25%) had 2-vessel disease and 25 (45%) had 3-vessel disease; 14 (25%) had greater than or equal to 1 prior bypass surgery, 35 (62.5%) were within 30 days of an acute infarction, 12 (21%) had left ventricular ejection fraction less than 0.50 and 7 (12.5%) were greater than 70 years of age. PTCA was successful in 61 (84%) vessels and 47 (84%) patients (greater than or equal to 1 vessel plus relief of angina). During index hospitalization, there were 2 deaths (3.6%), 4 myocardial infarctions (7.2%), 4 emergent bypass surgeries (7.2%) and 1 semiemergent bypass (1.8%) for technically unsuccessful PTCA. In follow-up from 3 to 36 months, there has been 1 additional myocardial infarction (1.8%), 1 late death (1.8%), 2 repeat PTCAs (3.6%), 6 crossovers to bypass (10.7%) and 38 patients (68%) have remained cardiac-event free. Although this angioplasty cohort is small and selected, these data raise the possibility that a prospective randomized comparison of PTCA versus bypass surgery might be feasible and appropriate in a subset of unstable angina patients who require intravenous nitroglycerin or IABP.

Short-term and long-term benefits of coronary angioplasty in unstable angina pectoris

Primary coronary angioplasty was attempted in 288 patients (206 men and 82 women) who presented with stable (50%) or unstable (50%) angina pectoris. The success rates of angioplasty and the subsequent revascularization requirements in these two angina categories were compared during a one year prospective follow-up. The site and distribution of coronary artery stenoses did not differ between the categories. Three hundred and five dilatations were attempted (149 in 144 patients with unstable angina and 156 in 144 patients with stable angina). Of these procedures, 265 (87%) were technically successful--133 (89%) in 128 patients with unstable angina and 132 (85%) in 120 patients with stable angina. Lower success rates were achieved in 29 attempted dilatations of vessels with chronic total occlusion (19 successful [66%], P = 0.002) and in 19 patients who presented with unstable angina after recent (within two weeks) infarction (10 patients with successful angioplasty, [53%], P less than 0.0001). Subsequent revascularization requirements after an initially successful angioplasty in 57 patients were greater in unstable (36 patients) than in stable angina (21 patients; P = 0.05) and reflected the greater frequency of repeat angioplasty in patients with unstable angina (22 patients) compared with those with stable angina (10 patients; P = 0.04) among patients with recurrent symptoms. At one year, 245 patients (85%)-121 treated for unstable angina and 124 treated for stable angina--experienced no angina during normal daily activities. We conclude that a primary angioplasty success rate of 89% can be achieved in patients with unstable angina pectoris but this rate is significantly lower in patients presenting after recent infarction. Repeat angioplasty for recurrent symptoms after a successful primary procedure is required more frequently in patients presenting with unstable angina.

Coronary angioplasty in patients with unstable angina pectoris: is there a role for thrombolysis?

Management of unstable angina has evolved progressively, and coronary angioplasty has recently been shown to be an effective treatment strategy for unstable angina. However, the procedure-related major complication rate is higher when compared with that for angioplasty in stable angina. The underlying pathophysiology may explain this higher complication rate. Rupture of an atherosclerotic plaque associated with thrombus formation is frequent in the pathogenesis of unstable angina. These processes lead to a critical reduction in myocardial blood supply, and coronary angioplasty may effectively interrupt this process. In contrast, coronary angioplasty itself may cause further injury of the already ulcerated intima, have the potential to intensify the ongoing thrombogenic process and lead to an increased frequency of abrupt closure of the artery during the procedure. Therefore, intracoronary streptokinase was used in the procedure in those patients with abrupt closure of the artery immediately after dilation to attempt to improve the immediate result. Coronary angioplasty was attempted in 200 consecutive patients with unstable angina. Initial success in crossing the obstructed artery was achieved in 196 patients; however, an abrupt closure immediately after dilation occurred in 21 of these patients. Of these 21 patients, 12 were also treated with intracoronary streptokinase, and successful dilation was achieved in 9 patients without evidence of necrosis or the need for emergency bypass surgery. Of the remaining nine patients, four successfully underwent redilation with a larger-sized balloon, four underwent urgent surgery (one death postoperatively) and one was treated conventionally. Final success was achieved in 188 patients (94%) without death, the need for emergency surgery or evidence of myocardial necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)