Delayed coronary occlusion following primary successful angioplasty: Management and outcome

Summary The treatment of delayed coronary occlusion after primary successful percutaneous transluminal coronary angioplasty (PTCA) is more difficult because surgical standby is often not available. The purpose of this study was to assess the therapeutic approaches and outcome of patients with delayed coronary occlusion from 30 to 180 minutes after successful PTCA. A delayed occlusion occurred in 18 (0.9%) (61±11 years; malen=14, femalen=4) out of 2065 consecutive patients after PTCA. In 11 patients the dilated stenoses were located in the left descending artery, while seven patients had the stenosis in the right coronary artery. Twelve patients had unstable or postinfarction angina. The time interval between completion of PTCA and the onset of chest pain was 64±39 minutes. Immediate i.v. nitroglycerin resulted in no relief of the symptoms in any patient. One patient was operated upon at once, and one was given i.v. thrombolysis resulting in pain relief and reversal of ECG changes. The remaining 16 patients returned initially to the catheterization laboratory, where the occluded vessels were opened by mechanical recanalization. Three of them remained in stable condition. Due to impending reocclusion surgery was necessary in four patients and thrombolysis was performed in nine. After thrombolysis the vessel remained open in four patients. The other five needed bypass surgery on the day of PTCA. Myocardial infarction developed in nine patients (maximal CK 673±488 units/l). In conclusion, delayed occlusion after successful PTCA is a rare complication occurring primarily in patients with unstable angina. Mechanical recanalization opened the occluded vessel in most patients, and myocardial infarction was prevented in 50%.Abbreviations PTCA percutaneous transluminal coronary angioplasty - CK creatine kinase - ECG electrocardiogramm - SD standard deviation     

Percutaneous transluminal coronary angioplasty of focal coronary lesions after cardiac transplantation

Summary Transplant coronary artery disease is the greatest impediment to long-term survival beyond the first year after cardiac transplantation. Transplant coronary artery disease shows a heterogeneous angiographic appearance, but focal stenoses can occur alone or at least predominate. Based on an angiographic indication 35 critical focal lesions causing narrowing by 75% or more were treated by PTCA during 23 procedures in seven patients 18–84 months after cardiac transplantation. Three patients each underwent only one procedure and four underwent repeated procedures [2, 3, 4 and 11, respectively]. Primary success was achieved without any complication in 35 of 35 lesions (100%). The mean degree of stenosis was reduced from 86±9% to 28±17% (P<0.001). The rate of restenosis was 18/29 (62%) at a mean of 4 months after angioplasty. Four patients are alive and free of adverse effects (symptoms, myocardial infarction, repeated percutaneous transluminal coronary angioplasty, retransplantation) 16±10 months after their last angioplasty. One patient underwent a successful second heart transplantation 26 months after the first angioplasty. Two patients died, 1 and 31 months after the last angioplasty. In conclusion, percutaneous transluminal coronary angioplasty can be performed safely with an excellent primary success rate in critical focal transplant coronary artery disease. The rate of restenosis is higher than in native coronary artery disease. Long-term follow-up depends on the individually variable accelerated nature of graft atherosclerosis.Abbreviations PTCA percutaneous transluminal coronary angioplasty - TxCAD transplant coronary artery disease - HTX heart transplantation - LAD left anterior decending artery - CFX circumflex artery - RCA right coronary artery     

Technical achievement: transthoracic Doppler echocardiography can be used to detect LAD restenosis after coronary angioplasty.

We investigated the capability of transthoracic Doppler echocardiography (TTE) to detect and quantify the severity of restenosis in the left anterior descending coronary artery (LAD) after percutaneous transluminal coronary angioplasty (PTCA). We studied 10 consecutive patients assigned for quantitative coronary angiography (qCA) due to a recurrent angina pectoris after PTCA of the LAD. The LAD was visualized by TTE, and the presence of local turbulence and an increase in the blood flow velocity was regarded to indicate coronary stenosis. To assess the severity of the stenosis, the increase of blood flow velocity was measured. Angiography showed stenoses of various degrees (27-100%) in all patients. All stenoses were detectable using TTE. Moreover, the ratio of maximal blood flow velocity at the site of stenosis to the pre-stenotic blood flow velocity (M/P-ratio) correlated significantly with the reduction of the luminal diameter of LAD (r = 0.85, P < 0.003). A M/P-ratio higher than 3.0 predicted a diameter reduction of 50% or higher with sensitivity and specificity of 100% in patients with a subtotal stenosis (n = 9). Our results indicate that stenoses in the LAD could be found and the severity of the stenoses could be quantified reliably with TTE. This approach is totally non-invasive and less expensive than coronary angiography and can be used clinically in clarifying restenosis after coronary angioplasty.     

A comparison of angioplasty with medical therapy in the treatment of single-vessel coronary artery disease. Veterans Affairs ACME Investigators.

BACKGROUND. Despite the widespread use of percutaneous transluminal coronary angioplasty (PTCA), only a few prospective trials have assessed its efficacy. We compared the effects of PTCA with those of medical therapy on angina and exercise tolerance in patients with stable single-vessel coronary artery disease. METHODS. Patients with 70 to 99 percent stenosis of one epicardial coronary artery and with exercise-induced myocardial ischemia were randomly assigned either to undergo PTCA or to receive medical therapy and were evaluated monthly. The patients assigned to PTCA were urged to have repeat angioplasty if their symptoms suggested restenosis. After six months, all the patients had repeat exercise testing and coronary angiography. RESULTS. A total of 107 patients were randomly assigned to medical therapy and 105 to PTCA. PTCA was clinically successful in 80 of the 100 patients who actually had the procedure, with an initial reduction in mean percent stenosis from 76 to 36 percent. Two patients in the PTCA group required emergency coronary-artery bypass surgery. By six months after the procedure, 16 patients had had repeat PTCA. Myocardial infarction occurred in five patients assigned to PTCA and in three patients assigned to medical therapy. At six months 64 percent of the patients in the PTCA group (61 of 96) were free of angina, as compared with 46 percent of the medically treated patients (47 of 102; P less than 0.01). The patients in the PTCA group were able to increase their total duration of exercise more than the medical patients (2.1 vs. 0.5 minutes, P less than 0.0001) and were able to exercise longer without angina on treadmill testing (P less than 0.01). CONCLUSIONS. For patients with single-vessel coronary artery disease, PTCA offers earlier and more complete relief of angina than medical therapy and is associated with better performance on the exercise test. However, PTCA initially costs more than medical treatment and is associated with a higher frequency of complications.     

Percutaneous transluminal coronary angioplasty without thrombolytic therapy in acute myocardial infarction

Percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) was performed in 42 patients (37 males, 5 females, average age 53 years). Recanalization of the stenosed or occluded infarction-related coronary artery was achieved within the first 14 to 50 min from the start of catheterization in 95% of cases. Three patients were transferred for emergency coronary bypass graft surgery (CABG) because of major multiple coronary lesions, immediately after angiographically successful PTCA. One of the patients died in cardiogenic shock. Four patients died between days 5 to 15 of hospitalization. Repeat coronary angiography was done in 27 of the 37 survivors at a mean interval of 2.5 months after AMI. Total reocclusion was found in 6 patients. The recanalized coronary artery had prevented its patency in 78% of the cases; restenosis was found in 5 patients, and was successfully dealt with renewed angioplasty in 3 patients. While the ejection fraction (EF) had remained largely unchanged, there was some improving tendency of left ventricular segmental kinetics, particularly in case of anterior wall infarction. PTCA without thrombolytic therapy seems to provide an effective and relatively prompt recanalizing procedure in the complex management of AMI.     

Multiresolution wavelet analysis of the body surface ECG before and after angioplasty

Electrocardiographic recordings of patients with coronary artery stenosis, made before and after angioplasty, were analyzed by the multiresolution wavelet transform (MRWT) technique. The MRWT decomposes the signal of interest into its coarse and detail components at successively finer scales. MRWT was carried out on different leads in order to compare the P-QRS-T complex from recordings made before with those made after percutaneous transluminal coronary angioplasty (PTCA). ECG signals before and after successful PTCA procedures show distinctive changes at certain scales, thus helping to identify whether the procedure has been successful. In six patients who underwent right coronary artery PTCA, varying levels of reperfusion were achieved, and the changes in the detail components of ECG were shown to correlate with the successful reperfusion. The detail components at scales 5 and 6, corresponding approximately to the frequencies in the range of 2.3–8.3 Hz, are shown to be the most sensitive to ischemia-reperfusion changes (p<0.05). The same conclusion was reached by synthesizing the post-PTCA signals from pre-PTCA signals with the help of these detail components. For on-line monitoring a vector plot, analogous to vector cardiogram, of the two most sensitive MRWT detail components is proposed. Thus, multiresolution analysis of ECG may be useful as a monitoring and diagnostic tool during angioplasty procedures.     

T lymphocyte activation and restenosis after percutaneous transluminal coronary angioplasty.

We investigated the relation between the activation of T lymphocytes and the occurrence of restenosis after percutaneous transluminal coronary angioplasty (PTCA) in 10 stable angina patients. Recent studies have suggested that PTCA causes an inflammatory response, which may affect restenosis after angioplasty. Soluble interleukin-2 receptor (sIL-2R) is a useful marker to evaluate the activation of T lymphocytes. sIL-2R was measured before and 2 h after successful PTCA, and 3-month follow-up coronary angiography was done to observe restenosis. Four of 10 patients showed restenosis. The restenosis group of 4 patients had a higher level of sIL-2R after PTCA than the no-restenosis group of 6 patients (495 vs. 274 U/ml, p < 0.01). This study suggests that sIL-2R may offer prognostic information after elective PTCA and identify a subgroup of patients at high risk for clinical restenosis in a few months.     

Catheter dilatation of coronary artery stenosis. 2 years' experience

We report our experiences with the first 40 patients treated by percutaneous transluminal coronary angioplasty (PTCA) over the past two years. The technique was successful in 25 patients (63%) with 28 coronary stenoses, reducing the degree of stenosis from a mean of 81 to 25% (p less than 0.001) and the coronary pressure gradient from 70 to 26 mm Hg (p less than 0.001). Because of reduction of coronary blood flow with evolving myocardial infarction an emergency aortocoronary bypass surgery was necessary in two patients (5%). An additional patient suffered a myocardial infarction (2.5%). Within a follow-up observation of 6 months, restenoses occurred in 7 patients (33%); 5 of them were treated with bypass surgery and one was redilated successfully. Our first experiences with PTCA are similar to the results of other institutions.     

The role of balloon angioplasty in the management of coronary artery disease

PTCA is a new technique for the treatment of certain patients with coronary artery disease. It involves dilatation of stenotic segments of artery using a balloon catheter, and is carried out in cardiac catheterization laboratories. If successful, the need for coronary bypass surgery may be removed, although some patients with initially successful PTCA will come to surgery eventually. Successful PTCA is associated with relief of angina, improved angiographic appearances and coronary perfusion. The primary success rate is between 65% and 80%, and the restenosis rate approximately 25%. 80% of patients will be angina free one year after PTCA. In this paper the indications, contraindications, technology, results and complications are discussed.     

Recanalization of chronic coronary occlusions

Recanalization of occluded coronary arteries is the aim of percutaneous interventions with acute myocardial infarction. Moreover, chronic coronary occlusion is a common finding during diagnostic coronary angiography and is often a contributing factor in the choice of revascularisation by surgery rather than by percutaneous coronary interventions (PCI). An occluded coronary artery with some degree of collateral supply is functionally comparable to a severe coronary stenosis. Therefore, recanalization of chronic occluded coronary arteries results in less angina and often in improvement of left ventricular function. Success is limited in particular in longer lasting occlusions. Characterization of lesions, where recanalization can performed successfully is warranted. We correlated primary success rates of attempted coronary recanalizations with localisation of lesions and procedural characteristics. We analyzed records of 124 consecutive patients, who underwent attempted coronary recanalization of chronically occluded coronary arteries at our institution in 1998. Revascularisation was successful in 84 (64 male, 20 female) of 124 (92 male, 32 female) patients. Therefore, success rate was 67.7% (69.9% in men, 62.5% in women, p = 0.42). Target vessel was the left anterior descending artery (LAD) in 49 cases. Success rate in the LAD did not differ significantly from that in "non-LAD"-vessels (65.3% versus 69.3%; p = 0.35). Successful recanalizations were performed using only one guide-wire in 77.3%. More than one guide-wires were used during procedures without success in 44.5% and exceeded use in successful interventions (p < 0.05). Procedures, failing to be successful after an attempt with a first guide-wire, could be performed successfully using at least a second wire in 50%. Coronary stenting after recanalization has been performed in 84.4% in the LAD and in 59.7% in non-LAD vessels (p < 0.01). Success rate of attempted recanalizations of chronic occluded coronary arteries in unselected patients is high. Most procedures can be performed successfully using only one guidewire. Additional use of other wires can increase success rates in procedures with primary failure to pass the occlusion. Stenting has been performed in three out of four patients with successful recanalization of chronically occluded coronary arteries.     

Dosierung der intrakoronaren Urokinase-Infusion beim akuten Myokardinfarkt

Summary In 11 patients with acute myocardial infarction (mean age 52±6 years) coronary angiography was performed 4.5±3.6 h after the onset of symptoms. The infarct-related artery was in 7 cases the right coronary artery and in 4 cases the left anterior descending branch of the left coronary artery. The infarct-related artery showed total or subtotal occlusion and no perfusion (Thrombolysis in Myocardial Infarction trial (TIMI) grade 0 or 1). In 7 cases Urokinase was infused intracoronarily at a dosage of 250 000 IU over 30 min, but in only 1 case partial reperfusion was achieved. However, all patients treated with 500 000 IU Urokinase over 30 min or 1 Mill IU over 60 min had successful reperfusion (TIMI grade 2 or 3). Thus, it appears that 500 000 IU up to 1 Mill IU of Urokinase over a period of 30 to 60 min is adequate for intracoronary thrombolysis in patients with acute myocardial infarction.

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Abkürzungsverzeichnis TIMI Thrombolysis in Myocardial Infarction trial - PTCA Perkutane transluminale Koronarangioplastie - RCA rechte Koronararterie - RIVA Ramus interventrikularis anterior - IE Internationale Einheiten - min Minuten     

Psychologic predictors of psychosocial and medical outcomes in patients undergoing coronary angioplasty

The relationship between psychologic variables (the match between repressive style and level of cardiac information, and anxiety level) and medical complications, re-stenosis (renarrowing), and psychosocial adjustment was studied in 97 patients undergoing percutaneous transluminal coronary angioplasty (PTCA) for treatment of narrowed coronary arteries. Three major findings emerged for outcomes measured 6 months after PTCA: repressors with a high level of cardiac information (coping style-information level mismatch) and no history of heart attack were at higher risk for late medical complications (p less than 0.001); sensitizers with a low level of cardiac information (coping style-information level mismatch) and whose PTCA was only moderately successful were at higher risk for re-stenosis of the artery previously widened during PTCA (p less than 0.01); and patients who were more anxious during hospitalization had poorer social functioning and more mood disturbance 6 months after PTCA (p less than 0.05). Thus, psychologic, information, and medical factors are important in predicting 6-month outcomes in patients undergoing PTCA.     

Aspirin and dipyridamole in the prevention of restenosis after percutaneous transluminal coronary angioplasty

To examine the role of antiplatelet therapy in the prevention of arterial restenosis after percutaneous transluminal coronary angioplasty (PTCA), we conducted a randomized, double-blind, placebo-controlled study in 376 patients. The active treatment consisted of an oral aspirin-dipyridamole combination (330 mg-75 mg) given three times daily, beginning 24 hours before PTCA. Eight hours before PTCA, the oral dipyridamole was replaced with intravenous dipyridamole at a dosage of 10 mg per hour for 24 hours, and oral aspirin was continued. Sixteen hours after PTCA, the initial combination was reinstituted. Treatment was continued in patients with a successfully dilated vessel until follow-up angiography four to seven months after PTCA--or earlier, if symptoms dictated. Of 249 patients who underwent follow-up angiography, 37.7 percent of patients receiving the active drug had restenosis in at least one segment, as compared with 38.6 percent of patients taking placebo (P not significant). The number of stenotic segments was virtually the same in the two groups. Among the 376 randomized patients, there were 16 periprocedural Q-wave myocardial infarctions--13 in the placebo group and 3 in the active-drug group (6.9 percent vs. 1.6 percent, P = 0.0113). Although the use of this antiplatelet regimen before and after PTCA did not reduce the six-month rate of restenosis after successful coronary angioplasty, it markedly reduced the incidence of transmural myocardial infarction during or soon after PTCA. Thus, the short-term use of antiplatelet agents in relation to PTCA can be recommended.     

冠状动脉内放射治疗防止血管成形术后再狭窄的研究进展

再狭窄已经成为经皮冠状动脉腔内成形术(ＰＴＣＡ)广泛应用的最大障碍 ,约 4 0 %～ 60 %的患者在成功的完成ＰＴＣＡ术之后数月内发生再狭窄[1] 。再狭窄的机制非常复杂 ,目前多认为包括以下几方面 :术后血管弹性回缩 ;血管的重塑、平滑肌细胞迁移、增殖、细胞外基质形成新生内膜 ;局部血栓的形成与机化 ;许多细胞因子和生长因子的分泌参与再狭窄的过程[2 ,3] 。针对再狭窄的发生机制 ,许多研究试图通过各种药物进行预防 ,包括肝素和血小板ＧＰＩＩｂ -ＩＩＩａ受体拮抗剂在内的所有药物在临床实践中并未明显降低再狭窄率。支架置入术能够减…     

Coronary balloon angioplasty: a technique that is here to stay

In this article, developments in the technique of percutaneous transluminal coronary angioplasty (PTCA) since its introduction in 1977 as well as current trends and likely future directions of the technique are outlined. Over the last 6 or 7 years, there has been a dramatic widening of the applications PTCA to include patients with complex anatomic lesions and adverse clinical features. Despite the large percentage of such difficult cases currently presenting for PTCA, an initial success rate in excess of 90% is achieved. Increased operator experience and continuing refinements in angioplasty technology are important factors in this continuing success of PTCA. Early restenosis remains the major drawback of the technique; this complication is usually treated by repeat PTCA. Available information indicates that the long-term outcome of patients after successful PTCA is excellent, with a low incidence of late restenosis and progression of disease. The relative efficacy of PTCA and coronary bypass surgery in patients with multivessel disease is, at present, uncertain.     

Microalbuminuria is no risk factor for restenosis following percutaneous transluminal coronary angioplasty

Summary Microalbuminuria is known to be associated with an increased risk for cardiovascular disease. It is detectable in acute myocardial infarction and could therefore also be a risk factor for reocclusion after percutaneous transluminal coronary angioplasty (PTCA). In our study follow-up coronary angiography was performed in 50 consecutive patients with a mean age of 56 years (38–70) on average 14 months after successful PTCA. Restenosis was defined as a decrease in diameter of 25% or more of the original result and one of at least 50% in vessel diameter. In the restenosis group there were 23 patients, and 27 showed no restenosis. The family history and anamnestic risk profile, results of the initially performed coronary angiography, and laboratory risk factors were comparable in the two groups. Median microalbumin was 11.2 mg/g creatinine in those with restenosis and 9.8 mg/g creatinine in those without. Using a cutoff of 10.0 mg/g creatinine, 12 of 23 patients with restenosis (52%) and 10 of 27 patients without (37%) were positive for microalbuminuria (NS). The incidence of microalbuminuria was higher in both groups compared to historical controls. Thus, in the restenosis group the incidence of microalbuminuria tended to be higher than in the nonrestenosis group, but since this difference did not reach statistical significance, it cannot be used to predict the risk of reocclusion after PTCA.Abbreviations PTCA percutaneous transluminal coronary angioplasty - MA microalbuminuria - R restenosis group - NR group without restensosis     

Overcommitment predicts restenosis after coronary angioplasty in cardiac patients

The objective of this study is to examine the role of a particular stress-enhancing psychosocial risk factor, termed overcommitment, in predicting restenosis after successful percutaneous transluminal coronary angioplasty (PTCA). Overcommitment defines a personal pattern of coping with demands characterized by excessive striving in combination with a strong desire of being approved and esteemed. One hundred six consecutive male patients with coronary artery disease who underwent PTCA were followed over a mean of 12 months. The restenosis rate as defined by quantitative angiography was 34%. Multivariate analysis revealed independent effects of high density lipoprotein cholesterol (odds ratio [OR] 3.19), age (OR 3.43), and overcommitment (OR 2.86) on risk of restenosis. In conclusion, a stress-enhancing psychosocial person characteristic termed overcommitment acts as an independent predictor of coronary restenosis after PTCA. As overcommitment is subject to cognitive-behavioral intervention, results have implications for a more comprehensive approach to secondary prevention in cardiac patients. This research was supported by the German Research Foundation (DFG-SFB 242/D18). We thank Dr. Myriam Valk-Draad for her collaboration.     

Exercise thallium-201 scintigraphy in the localization of myocardial ischaemia

We performed a retrospective study in order to study the ability of thallium-201 exercise scintigraphy to detect and to localize coronary artery perfusion defects (in comparison with a recent coronary angiogram). We studied 81 patients (67 males); their average age was 52.3 years (men 50.5 and women 54.1 years). They performed a pulse-conducted cycle exercise test, and 2 min before end of exercise 75 MBq of thallium-201 was infused intravenously, and tomographic images were reconstructed by using a Siemens-Rota SPECT gamma camera immediately and 4 h after exercise. The thallium-201 uptake defects were attributed to different coronary arteries, and the results were compared with a coronary angiogram made afterwards in 48 patients. The groups of one-, two- and three-vessel disease were 27, 21, and 21 patients, and only 12 patients did not have significant (over 50%) stenoses. The latter had the highest ejection fraction and working capacity. Sensitivity of thallium-201 exercise scintigraphy was 65%, whereas that of exercise ECG was 41% in patients with a low ejection fraction, while in the whole material the sensitivity of thallium-201 scintigraphy was 91% and that of exercise ECG was 54%. A stenosis in the right coronary artery was best localized by the thallium-201 scintigram (86% correctly); a stenosis in the left anterior descending artery was localized correctly in 75% of the cases, but a stenosis in left circumflex artery was localized correctly only in 44%. We conclude that exercise thallium-201 scintigraphy is a useful method not only in detecting but also in localizing coronary artery disease.     

The impact of the preoperative severity of target-vessel stenosis on the short-term patency of radial artery grafts

The fate of a grafted radial artery remains unknown. The purpose of this study was to determine whether the preoperative severity of stenosis of the target vessel influence short-term patency of radial artery (RA) grafts used as coronary artery bypass conduits. In 54 patients who had coronary artery bypass grafting (CABG) with RA grafts, RA patency was determined with multi-slice computed tomography (MSCT) 1 year after CABG. These patients were divided into three groups on the basis of the percentage of the target vessel stenosis: mild (< 60%, n=17), moderate (60% to 79%, n=19), and severe (>/= 80%, n=18). MSCT was also performed 1 week later to exclude early occlusion of RA grafts. In 3 patients, the MSCT failed to adequately discriminate the status of the RA graft due to poor image resolution. The overall incidence of RA occlusion was 23.5% (12 of 51) at 1 year in the entire population. The mild stenosis, moderate stenosis and severe stenosis group showed an occlusion rate of 50% (8 of 16), 23.5% (4 of 17) and 0% (0 of 18), respectively. The severe stenosis group had significantly lower rate of RA graft occlusion compared to the mild stenosis group (p < 0.001) and moderate stenosis group (p < 0.05). No difference in occlusion between grafts used for the different coronary artery branches could be demonstrated. Preoperative severity of the target coronary artery significantly affected the short-term RA grafts patency. Correct indication is the key factor for short-term RA patency.     

冠脉成形术缺血性刺激前后血清IL-6、TNF-α水平的变化

目的:冠脉成形术(PTCA)引起的炎症反应始于术后早期。白细胞介素6(IL-6)、肿瘤坏死因子α(TNF-α)是主要的炎性细胞因子。本实验拟通过对比有或没有侧支循环病人PTCA前后IL-6、TNF-α水平的变化,探讨PTCA引起早期炎性反应的机制。方法:参照Leaman冠脉积分系统,对PTCA球囊阻断引起的缺血强度进行量化。计算正常对照组与冠心病组PTCA手术前后的IL-6、TNF-α水平变化,并进行相关性分析。结果:缺血性剌激前IL-6和TNF-α分别为(9.592±1.847)ng/L和(26.959±1.967)ng/L。在剌激后4h分别为(27.423±1.882)ng/L和(78.542±1.573)ng/L,呈显著差异。结论:IL-6、TNF-α是反映PTCA术后早期炎性反应的敏感指标。缺血积分可作为反映PTCA术中缺血/再灌注损伤程度的量化指标。侧支循环可减轻PTCA术后早期炎症反应。