Coronary angioplasty in patients aged 70 and over. Immediate results and later outcome

One hundred and ninety one consecutive patients over 70 years of age (127 men and 64 women, average age 75.6 years) underwent percutaneous transluminal coronary angioplasty (PTCA) between January 1986 and February 1989. One hundred and sixty patients had severe angina (20 Class III and 140 Class IV), 72 patients had previous myocardial infarction, 36 of which were recent (less than 1 month), and 6 patients had previously undergone coronary bypass surgery. The coronary lesions affected one vessel in 67 patients and more than one vessel in 124 patients. The left ventricular ejection fraction was less than 50% in 15 patients. Angioplasty was attempted on 245 lesions (228 stenoses and 17 occlusions): 1 lesion in 141 patients, 2 lesions in 46 patients, 3 lesions in 4 patients, with a primary success rate of 81% in stenotic and 41% in occluded arteries. There were 9 deaths (4.7%) 6 of which occurred in patients with multivessel disease and unstable angina; there were 6 Q-wave infarctions (3.1%), 8 non Q-wave infarctions (4.2%) and 3 emergency coronary bypass operations (1.6%). The first 123 patients of this series were followed up for an average of 18.8 months (7 to 37 months). Follow-up of the 100 patients successfully dilated (4 lost to follow-up) showed that 55 remained improved (53 asymptomatic), 25 had recurrent angina after the initial improvement due to restenosis in 19, progression of coronary athero-sclerosis in 3, restenosis and an evolution of coronary atherosclerosis in 1 and a lesion which had been neglected in 2 cases.(ABSTRACT TRUNCATED AT 250 WORDS)     

Triple vessel coronary angioplasty: acute outcome and long-term results

Triple vessel coronary angioplasty, defined as angioplasty of one or more lesions in each of the three major coronary arteries (left anterior descending, left circumflex, right coronary artery) was performed in 50 (11%) of 469 patients who had angioplasty of multiple vessels. There were 32 men and 18 women with a mean age of 56 years. All 50 patients had severe three vessel coronary disease and represent approximately 5% of patients with three vessel disease who had revascularization in this institution; 8 (16%) had previous coronary bypass surgery, and 23 (46%) had previous myocardial infarction. Unstable angina was present in 33 patients (66%) and 96% had Canadian Heart Association class III or IV angina; mean left ventricular ejection fraction was 57 +/- 11%. Angioplasty was performed in 176 vessels (3.5 vessels per patient, range 3 to 6) and in 250 lesions (5 lesions per patient, range 3 to 9); angiographic success was achieved in 240 lesions (96%) and 166 vessels (94%). Success in all vessels attempted was achieved in 40 (80%) of the 50 patients. Clinical success (angiographic success associated with clinical improvement) was obtained in all 50 patients in whom triple vessel angioplasty was performed; none of them required urgent bypass surgery and 5 patients (10%) had a non-Q wave myocardial infarction. In four other patients triple vessel angioplasty was planned but not performed because of failure to dilate the primary vessel; urgent bypass surgery was required in one of these, who developed a Q wave infarction. Thus, overall clinical success in 54 patients was 93%; the incidence rate of myocardial infarction was 11%, and that of urgent surgery 1.8%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Initial management and long-term clinical outcome of restenosis after initially successful percutaneous transluminal coronary angioplasty.

Restenosis remains a critical limitation after percutaneous transluminal coronary angioplasty (PTCA). The clinical experience with restenosis was reviewed in 1,490 patients who had restenosis of at least 1 site within 1 year of their PTCA. The source of data was the clinical database at Emory University. Patients who had previous coronary bypass surgery or PTCA and patients who underwent PTCA in the setting of acute myocardial infarction were excluded. When restenosis was angiographically documented, 363 were treated medically, 1,051 with repeat PTCA, and 76 with coronary bypass surgery. In the repeat PTCA group there were 778 patients who originally had 1-vessel disease and 273 with multiple vessel disease. Re-dilatation of restenotic sites was performed in 95%. Angiographic success of all lesions dilated was achieved in 99%. Coronary bypass surgery was required in 2.5% of patients with restenosis first treated with repeat PTCA. One patient with multiple vessel disease died. Coronary bypass surgery was performed in fewer patients aged greater than or equal to 65 years, but more patients with multiple vessel disease. Two (2.6%) of the coronary bypass surgery patients had Q-wave myocardial infarction and there were no deaths. In the PTCA group, 5-year actuarial survival was 95%, and cardiac survival 96%. Freedom from cardiac events or further revascularization procedures was 51% at 5 years. Patients treated with PTCA and medically treated patients had similar cardiac survival rates. The most important correlates of cardiac survival were age and the presence of diabetes mellitus. At 5 years, cardiac survival without diabetes was 97 and 83% with diabetes (p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Percutaneous transluminal coronary angioplasty in evolving acute myocardial infarction

In 29 patients with evolving acute myocardial infarction, acute reperfusion of the infarct-related coronary artery was attempted using percutaneous transluminal coronary angioplasty (PTCA). Before PTCA, angiography showed 23 totally occluded and 6 severely stenotic infarct-related coronary arteries. PTCA was initially successful in 25 of 29 patients (86%). Reocclusion occurred in 4 patients within 12 hours after successful PTCA and was associated with new electrocardiographic changes or recurrence of symptoms. In 17 patients the infarct-related coronary artery remained patent at early follow-up; late stenosis occurred in 4 patients. Recurrence of stenosis was accompanied by development of angina. No clinical or angiographic features distinguished those with ultimate vessel patency, occlusion or recurrence of stenosis. On follow-up, ventricular function appeared better preserved or improved in those with a patent infarct-related coronary artery than in those with an occluded infarct-related coronary artery. Further studies are warranted to compare PTCA and streptokinase as primary reperfusion modalities in evolving acute myocardial infarction.     

Complications of emergency coronary angioplasty for acute myocardial infarction]

To assess the incidence and consequences of complications occurring during emergency percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI), we studied 347 patients who underwent PTCA within 24 hours after the onset of AMI. Acute occlusion occurred in 29 patients (8.4%), of whom 16 patients underwent successful repeat PTCA. All of them survived until hospital discharge. The in-hospital reocclusion rates of these 16 patients were comparable to those of patients who had not experienced acute occlusion (18.8 vs 12.8%, ns). In the remaining 13 patients, reperfusion were not successful after acute occlusion, and 6 died. Side branch occlusion occurred in 21 patients (6.1%). Left circumflex artery occlusion occurring during PTCA for the proximal left anterior descending artery was fatal in 3 patients. Right ventricular branch occlusion during PTCA for the middle of the right coronary artery resulted in intractable right ventricular infarction in one patient, and he died. Among 14 patients who underwent repeat angiography, 13 had a patent side branch which had been occluded during PTCA. One patient had coronary rupture and died. During PTCA of the proximal left anterior descending artery, acute occlusion of the artery without reperfusion or occlusion of the left circumflex artery was often fatal. However, the prognosis of acute occlusion was relatively good, if repeat PTCA was successful and most of the occluded side branches remained patent in the chronic state.     

Mechanism of clinical onset and outcome of coronary disease before 40 years of age. 148 cases

This study reviewed the clinical histories of 148 coronary patients aged 34 +/- 5 years (20-40 years) documented in the same cardiology unit. Myocardial infarction was the presenting condition in 114 patients (77%): inaugural 65%, with prodrome 7%, asymptomatic 4%. The presentation was angina pectoris in 32 patients (22%): effort angina 15%, unstable angina 7%. Two patients had other symptoms (1%). The coronary lesions were significant (greater than 50%) in 112 patients (77%) which included 41% single vessel diseases and 36% multiple vessel diseases. The coronary lesions were insignificant in 10 patients (7%) and absent in 21 (15%) (33% under and 11% over 30 years of age). After an average follow-up of 48 months (range 1 to 10 years), 20 of the 32 patients presenting with angina developed myocardial infarction and 6 had episodes of unstable angina (65% in the first year following diagnosis). Six patients had no serious coronary events, but thereafter, 3 died. Fifteen patients (47%) are asymptomatic (including 8 after coronary bypass surgery). Ten patients are symptomatic. Of the 114 patients with inaugural myocardial infarction, 3 have died, 67 (58%) are symptomatic; the average number of risk factors per patient was related to age and to the degree of coronary artery disease. The left ventricular ejection fraction was significantly higher in asymptomatic patients than in those who had presented a coronary event after myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)     

Safety and efficacy of percutaneous transluminal coronary angioplasty in patients with left ventricular dysfunction.

The risks and long-term outcome after 845 elective percutaneous transluminal coronary angioplasties (PTCA) in patients with left ventricular (LV) dysfunction (ejection fraction less than or equal to 40%) were examined. Procedural results were compared with 8,117 consecutive procedures in patients with ejection fractions greater than 40%. The patients with LV dysfunction were older (63 vs 60 years, p less than 0.01), had a greater incidence of prior myocardial infarction (84 vs 45%, p less than 0.001), prior bypass surgery (39 vs 21%, p less than 0.001), 3-vessel disease (62 vs 33%, p less than 0.001), and class IV angina (48 vs 41%, p less than 0.01) than the control group. Angiographic success was lower (93 vs 95%, p less than 0.01), and overall procedural mortality was increased ( 4 vs 1%, p less than 0.001) in the study group. Emergency surgery rates were identical (2%). No significant difference was found in rates of nonfatal Q-wave myocardial infarction (2 vs 1%). At mean follow-up of 33.5 months, 15% of the patients with LV dysfunction required late bypass surgery, 27% underwent repeat PTCA, and 59% were angina free. Actuarial survival at 1 and 4 years was 87 and 69%, respectively. Cox regression analysis identified 3-vessel disease, age greater than or equal to 70 years, class IV angina and incomplete revascularization as correlates of long-term mortality. These data suggest that PTCA may be an effective treatment for coronary artery disease in patients with LV dysfunction.     

Predictors of adverse outcome 10 years after coronary angioplasty

To determine which factors before percutaneous transluminal coronary angioplasty (PTCA) predict long-term outcome, we evaluated the clinical follow-up data from 535 patients 10 years after single-vessel PTCA. Events were defined as death, myocardial infarction, bypass surgery or repeat PTCA. During the follow-up period 79 patients (15%) died, 59 patients (11%) suffered a myocardial infarction, 107 patients (20%) had coronary artery bypass surgery and 141 patients (26%) underwent a redilatation. To determine the predictors of 10-year follow-up, 12 patient-related and 9 lesion parameters were analyzed by logistic regression analysis. Mortality was independently increased in patients with diabetes, with multi-vessel disease, after a previous myocardial infarction and in smokers. The presence of multi-vessel disease, symptoms of a higher angina class and younger age increased the risk for undergoing bypass surgery. In the statistical model with lesion parameters, the risk of bypass surgery was decreased if the stenosis was located in the distal segment of the coronary vessel and by a higher minimal luminal diameter before PTCA. CONCLUSION: Logistic regression analysis identified multi-vessel disease, diabetes, smoking and a previous myocardial infarction as independent clinical predictors of an adverse outcome 10 years after coronary angioplasty. Lesion parameters before PTCA seem to be less important with regard to the long-term outcome after PTCA.     

Results of percutaneous transluminal coronary angioplasty for angina pectoris early after acute myocardial infarction

Between May 1980 and July 1985, 70 patients underwent percutaneous transluminal coronary angioplasty (PTCA) for angina occurring 24 hours after and within 30 days of acute myocardial infarction (32 with Q-wave infarction and 38 with non-Q-wave infarction). One-vessel disease was present in 42 (60%) and multivessel in 28 (40%); the mean ejection fraction was 0.56 (greater than or equal to 0.50 in 77% of patients). PTCA was successful in 56 patients (80%) and after introduction of steerable dilating systems in February 1983 this rate became 86%. The success rate for complete occlusions was 76%. The interval from myocardial infarction to PTCA was similar in patients with successful dilation (12.7 +/- 8.1 days) and those without (13.4 +/- 8.0 days). PTCA failed in 14 patients (20%); 8 underwent emergency coronary artery bypass for acute occlusion and 4 of 6 patients whose lesions could not be crossed had elective bypass surgery. There was 1 operative death. No patient sustained a Q-wave infarction. Three patients had non-Q-wave infarctions after technically successful PTCAs. Mean follow-up was 27 months (6 to 67 months). Of the 56 patients successfully dilated, 14 (25%) had 15 cardiac events during follow-up: death (1), non-Q-wave infarction (2), repeat PTCA (7), coronary bypass (4) and recurrence of severe angina (1). The cumulative mortality was 3% and the reinfarction rate was 7% (no Q-wave reinfarctions). Forty-two (60%) of the 70 patients were free of complicating events acutely and during follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)     

Surgical treatment of acute myocardial infarction

In 1989 the following indications for surgical treatment of acute myocardial infarction are: (1) acute evolving myocardial infarction less than 6 h from onset, in patients in whom percutaneous transluminal coronary angioplasty (PTCA) or streptokinase (SK), depending on the coronary anatomy, has been unsuccessful; if single vessel disease, coronary artery bypass grafting (CABG) is unlikely; if multiple vessel disease, CABG is preferable to SK/PTCA unless a very major 'culprit' lesion can be identified with certainty; (2) postinfarction angina hours to days after a transmural myocardial infarction unyielding to maximal medical therapy and in patients with a coronary artery obstruction not amenable to PTCA; (3) occlusion of a coronary artery during cardiac catheterization that cannot be fixed by PTCA and/or SK; (4) occlusion of a coronary artery during PTCA causing hemodynamic obstruction and a threatened myocardium subtended by the obstructed coronary artery; (5) balloon-dependent patients in cardiogenic shock without mechanical defects who have adequate residual left ventricular function as determined by regional wall motion studies; (6) ventricular septal defect secondary to myocardial infarction unless there is terminal organ damage; (7) mitral valve replacement with coronary bypass for acute papillary muscle rupture; (8) semi-emergency cardiac transplantation, either with or without a mechanical bridge to transplant in young individuals (less than 50 years) who have suffered massive destruction of left ventricular myocardium by an acute coronary occlusion with or without recurring ventricular tachyarrhythmias. Ejection fraction in this clinical category is always under 0.20 and usually under 0.15.     

Short-, medium-, and long-term follow-up after percutaneous transluminal coronary angioplasty for stable and unstable angina pectoris

The first 840 consecutive patients who underwent percutaneous transluminal coronary angioplasty (PTCA) performed in the same institution were retrospectively assessed at an average follow-up period of 25 months after the initial procedure. The study population consisted of 506 patients with stable angina pectoris (group 1) and 334 patients with unstable angina pectoris (group 2). Clinical end points were death, nonfatal myocardial infarction, recurrent angina pectoris necessitating bypass surgery or repeat PTCA, and event-free survival. The two groups were comparable with respect to age, sex, previous myocardial infarction, ejection fraction, and number of diseased vessels. PTCA was successful in 83.0% of group 1 and 87.1% of group 2. Follow-up rates were expressed as events per attempted PTCA in a patient group. No difference in survival was observed between the two groups, the mortality rate being approximately 2.8% at 25 months. In the group with stable angina pectoris there was a lower incidence of nonfatal myocardial infarction within the first 24 hours after angioplasty; 4.3% vs 9.0% (p less than 0.01). During long-term follow-up the increase in the incidence of nonfatal myocardial infarction was similar, resulting in an overall long-term follow-up infarction rate of 8.3% and 14.2%, respectively (p less than 0.01). A higher event-free survival was observed in group 1 within 24 hours after PTCA: 93.7% vs 84.2% (p less than 0.01). During subsequent follow-up the difference in event-free survival between the two groups was no longer significant: 68.5% vs 61.2%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Complete Myocardial Revascularization by Single Session Triple Vessel Percutaneous Coronary Angioplasty and Provisional Stenting

Background: Although availability of stents has made percutaneous transluminal coronary angioplasty (PTCA) safer, single vessel angioplasty still represents 90% of procedures performed today. We report our initial experience with single session triple vessel angioplasty, using stents as needed to improve suboptimal balloon results. Patients: Fourteen patients (12 men, 85%), aged 67 ± 19 years were treated. All had triple vessel disease and angina. Mean left ventricular ejection fraction was 61%± 8%. Results: PTCA was attempted in all three coronaries or one of their major branches during the same procedure. Seventeen target lesions were in the left anterior descending coronary artery, 2 in a diagonal branch, 11 in the left circumflex, 2 in a marginal branch, 13 in the right coronary artery, 3 in the posterior descending, and 1 a saphenous vein graft. PTCA of 3.5 ± 0.7 sites/procedure was attempted. The success rate was 13 (93%) of 14 patients and 47 (96%) of 49 lesions. Thirty-four (69%) lesions were treated by implantation of one or several stents, and 10 (71%) of 14 patients received at least one stent. Hospital stay duration was 4 ± 2 days. One patient required repeat PTCA to treat subacute stent thrombosis 2 days after the procedure (creatine kinase [CK] peak < 2 times upper limit of normal). There were no in-hospital deaths, Q-wave infarction, or need for coronary artery bypass grafting (CABC). After a median follow-up period of 24 months (range 3–102), one (7%) patient had died of a noncardiac cause, three (21 %) had required repeat PTCA for restenosis in previously dilated lesions, and none had suffered a myocardial infarction. At follow-up, the median angina class was I (range I-II). Conclusion: For selected patients with three vessel disease, complete revascularization by single session PTCA and provisional stenting as needed is feasible, and is associated with a low rate of short- and long-term complications when successfully performed.     

Late reassessment of percutaneous transluminal coronary angioplasty results: clinical, exercise and angiographic follow-up

One hundred and forty-five patients underwent percutaneous transluminal coronary angioplasty (PTCA) in the authors' hospital between 1981 and 1983. Four have since died and all but one of the remainder were accounted for at follow-up 41 +/- 12 months later. Recurrence of angina was present in 28% of patients having successful PTCA versus 33% of patients with surgery for failed PTCA. Use of antianginal drugs and return to work was similar in the two groups. Mean treadmill time, peak heart rate, incidence of treadmill angina and exercise thallium-201 defects were not different in the two groups. Late follow-up coronary angiography in 60 patients who had successful PTCA showed a significant decrease in mean stenosis of the dilated segment from 31 to 23%. Of 25 patients who had late angiography after failed PTCA, three had satisfactory patency of the dilated segment. New significant coronary stenosis was seen in only 17% of patients not having coronary bypass surgery.     

Clinical characteristics of unstable angina in 162 consecutive cases

We surveyed the clinical characteristics, treatment, and prognosis of 162 patients with unstable angina, who were admitted to our center between 1985 and 1987. There were 112 males and 50 females, with a mean age of 65 years. The clinical characteristics according to the American Heart Association classification were new angina of effort in 21%, changing pattern in 61%, and new angina at rest in 18% of the patients. ECG recordings during attacks of angina were obtained in 70%, and ST elevation was detected in 11%, ST depression in 54%, and T wave abnormality in 5%. Coronary arteriography performed in 42% of the patients revealed single vessel lesion in 21%, two vessel lesion in 10%, three vessel lesion in 5%, and left main trunk lesion in 3% of the patients. Seventy-seven percent of the patients were controlled by medical therapy, including nitrates, calcium antagonists, and, in some cases, beta blockades. Three percent of the patients were controlled with intra aortic balloon pumping in addition to medical therapy. Coronary artery bypass graft surgery (CABG) was performed in 6% of the patients. Since 1987, percutaneous transluminal angioplasty (PTCA) was introduced in our center and PTCA was performed in 9 patients (6%). Restenosis of the dilated portions of the coronary artery was observed and PTCA was again performed in 2 of 9 patients (22%). All patients who received CABG or PTCA survived and have been free from angina or myocardial infarction. Non-fatal myocardial infarction occurred in 10 cases (5.6%) and fatal infarction occurred in one patient (0.6%).     

Emergency percutaneous transluminal coronary angioplasty for acute myocardial infarction in patients 70 years of age and older

Direct percutaneous transluminal coronary angioplasty (PTCA) was performed as the primary means of establishing reperfusion during acute myocardial infarction in 105 elderly patients (mean age +/- standard deviation 75 +/- 4 years) at a mean of 5.5 +/- 4.0 hours from symptom onset. Fifty-two patients (50%) had anterior infarctions, 70 (67%) had significant narrowing in greater than 1 vessel, and 12 (11%) were in cardiogenic shock. Primary success was achieved in 91% of the infarct-related arteries. Four patients with failed PTCA underwent emergency bypass surgery; 10 had early symptomatic reocclusion of the dilated vessel. There was 1 death acutely in the catheterization laboratory. The overall in-hospital mortality was 18%. Three-vessel coronary artery disease and cardiogenic shock on presentation were the strongest predictors of in-hospital death. Global ejection fraction improved from 54 +/- 13 to 61 +/- 15% (p less than 0.001). The 1- and 5-year survival rates, including in-hospital deaths, were 73 and 67%, respectively. It is concluded that direct PTCA is an effective means of salvaging ischemic myocardium during acute myocardial infarction in the elderly patient. It is associated with a high success rate and low complication rate. The short- and long-term survival in this high-risk group of patients are improved compared with survival rates in historical controls.     

Intravenous streptokinase during acute myocardial infarction. A prospective open study

To evaluate the efficacy of intravenous streptokinase in acute myocardial infarction (AMI) 108 patients received a high-dose (1.5 million units), short-term infusion (60 minutes) within 6 hours after onset of symptoms, followed by anticoagulation. Before discharge a submaximal exercise test and a coronary arteriography were performed in 100 surviving patients. Sixty-seven patients had a patent infarct-related vessel. Clinical reocclusion occurred in 21 patients. Left ventricular function was slightly, but not significantly, better in patients with patent infarct-related vessels: ejection fraction 59.5 +/- 13% versus 57.4 +/- 13%. Additional procedures were performed in 20 patients: percutaneous transluminal coronary angioplasty (PTCA) in 8 and coronary artery bypass surgery (CABG) in 12. The results indicate that streptokinase applicated during a 6 hour-time window is a potent thrombolytic agent in acute myocardial infarction with limited effect on global left ventricular function. Pre-discharge evaluation is necessary to screen patients for residual ischemia.     

High dose intravenous streptokinase in acute myocardial infarction--short and long term prognosis.

Streptokinase (1 million international units) was given intravenously over 30 or 60 minutes to 50 patients four hours or less after the onset of acute myocardial infarction. All were aged less than or equal to 70 years and had 4 mm or greater ST segment elevation in anterior or inferior leads. Rapid (mean 95 min) ST segment resolution, which was taken to indicate reperfusion of the myocardium, occurred in 36 (72%) patients. In these 36 the average time from onset of symptoms to peak creatine kinase, creatine kinase MB, and myoglobin was 9.45 hours, whereas it was 17 hours in the 14 patients in whom indirect criteria did not indicate reperfusion. Reperfusion arrhythmias were invariably present and ventricular tachycardia developed in five patients and ventricular fibrillation in two. The infarct related artery was seen to be open in 28 (70%) of the 40 patients who had delayed coronary arteriography. The frequency of patency in the infarct related artery was no different in patients given streptokinase less than 2 hours or between 2-4 hours from onset of symptoms nor did it differ when streptokinase was infused over 30 or 60 minutes. Mean left ventricular ejection fraction was 57% in those with a patient infarct related artery and 48% in those with an occluded vessel. Eight patients subsequently underwent elective percutaneous transluminal coronary angioplasty after successful thrombolysis and six had coronary artery bypass grafting. There were nine in-hospital reocclusions of the infarct related coronary arteries. Two bleeding episodes occurred; one required transfusion. Five of the 50 patients died in hospital. All of them had had an anterior myocardial infarction; four had bifascicular block and one had right bundle branch block. During follow up, four patients died, two suddenly and two from reinfarction. During follow up (mean 15 months) the frequency of reinfarction, dyspnoea, and angina was low and there was no difference in the proportions of patients returning to work between those with an open infarct related artery and those with a closed infarct related artery. Intravenous administration of high dose streptokinase to selected patients during the acute phase of myocardial infarction is a safe, effective, and practical method of thrombolysis. It must, however, be followed by coronary arteriography to select those patients in whom percutaneous transluminal coronary angioplasty or coronary artery bypass grafting will be helpful.     

Factors determining improvement in left ventricular function after reperfusion therapy for acute myocardial infarction: primacy of baseline ejection fraction

Improvement in left ventricular ejection fraction is a measure of salvage of ischemic myocardium after reperfusion therapy for acute myocardial infarction. The degree of improvement in left ventricular ejection fraction may be influenced by many factors. Therefore, 137 patients in whom paired radionuclide angiograms were obtained within 24 h of acute infarction and before hospital discharge were retrospectively evaluated to determine which factors most affect improvement in ejection fraction. Only baseline ejection fraction correlated significantly with improvement in ejection fraction by both univariate analysis (ejection fraction as a continuous variable; p less than 0.001; ejection fraction as a categorical variable, less than or equal to 45% versus greater than 45%, p less than 0.0001) and multivariate analysis (p less than 0.0001). Reperfusion status (patent versus occluded infarct artery) and extent of coronary artery disease (one, two or three vessel) were significant factors by multivariate but not by univariate analysis. Location of infarction, treatment modality and time to treatment did not correlate with change in ejection fraction by either statistical technique. Thus, of those factors tested, baseline left ventricular ejection fraction is the most potent predictor of improvement in ventricular function after acute infarction. Knowledge of baseline ejection fraction may be helpful in deciding whether to treat some patients with equivocal indications or contraindications for reperfusion therapy. Clinical trials of reperfusion strategies should stratify patients on the basis of baseline ejection fraction if ejection fraction is to be used as an end point for myocardial salvage.     

High dose intravenous streptokinase in acute myocardial infarction--short and long term prognosis

Streptokinase (1 million international units) was given intravenously over 30 or 60 minutes to 50 patients four hours or less after the onset of acute myocardial infarction. All were aged less than or equal to 70 years and had 4 mm or greater ST segment elevation in anterior or inferior leads. Rapid (mean 95 min) ST segment resolution, which was taken to indicate reperfusion of the myocardium, occurred in 36 (72%) patients. In these 36 the average time from onset of symptoms to peak creatine kinase, creatine kinase MB, and myoglobin was 9.45 hours, whereas it was 17 hours in the 14 patients in whom indirect criteria did not indicate reperfusion. Reperfusion arrhythmias were invariably present and ventricular tachycardia developed in five patients and ventricular fibrillation in two. The infarct related artery was seen to be open in 28 (70%) of the 40 patients who had delayed coronary arteriography. The frequency of patency in the infarct related artery was no different in patients given streptokinase less than 2 hours or between 2-4 hours from onset of symptoms nor did it differ when streptokinase was infused over 30 or 60 minutes. Mean left ventricular ejection fraction was 57% in those with a patient infarct related artery and 48% in those with an occluded vessel. Eight patients subsequently underwent elective percutaneous transluminal coronary angioplasty after successful thrombolysis and six had coronary artery bypass grafting. There were nine in-hospital reocclusions of the infarct related coronary arteries. Two bleeding episodes occurred; one required transfusion. Five of the 50 patients died in hospital. All of them had had an anterior myocardial infarction; four had bifascicular block and one had right bundle branch block. During follow up, four patients died, two suddenly and two from reinfarction. During follow up (mean 15 months) the frequency of reinfarction, dyspnoea, and angina was low and there was no difference in the proportions of patients returning to work between those with an open infarct related artery and those with a closed infarct related artery. Intravenous administration of high dose streptokinase to selected patients during the acute phase of myocardial infarction is a safe, effective, and practical method of thrombolysis. It must, however, be followed by coronary arteriography to select those patients in whom percutaneous transluminal coronary angioplasty or coronary artery bypass grafting will be helpful.     

Acute myocardial infarction late after coronary artery bypass grafting: angiographic findings and results of an invasive approach]

Patients who have undergone coronary artery bypass grafting may develop acute myocardial infarction late after surgery. It is not exactly known in these patients whether acute infarction is predominantly caused by occlusion of bypass or native vessels. Also, there is no systematic and prospective data available with respect to an invasive, revascularizing therapeutic approach. Therefore, acute coronary angiograms were obtained in 21 consecutive patients with acute infarctions and remote bypass grafting to elucidate mechanisms causing myocardial infarction in these patients, and to assess results of catheter-based recanalization.Infarction was causes by acute graft occlusion in 12/21 patients. Fibrinolysis and/or PTCA of grafts was successful in 6/8 attempts, direct PTCA of a native vessel was effective in 1/2 patients, 1 patient underwent emergency re-CABG, and another patient was treated noninvasively. Occlusion of native, ungrafted vessel caused infarction in 9 patients. Direct PTCA of native vessels was effective in 6/7 of those patients, 1 patient had re-CABG, and another patients was treated non-invasively. Together, catheter-based recanalization was obtained in 13/17 attempts. Thirty-day and 1 year mortality (after discharge) was 5% (1/21 patients) and 12%, respectively. Predischarge ejection fraction was 46%.In conclusion, acute occlusion of bypass grafts is responsible for about half of all cases of myocardial infarction in patients late after surgery. Direct angiography and individually tailored catheter-based recanalization in patients with acute myocardial infarction late after surgery yield promising results.