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.     

Comparative efficacy of primary angioplasty with stent implantation and thrombolysis in restoring basal coronary artery flow in acute ST segment elevation myocardial infarction: quantitative assessment using the corrected TIMI frame count

Following thrombolysis and primary percutaneous transluminal coronary angioplasty (PTCA) for acute ST segment elevation myocardial infarction, basal flow in the culprit artery is known to influence prognosis. The purpose of this study was to determine if differences exist in basal flow in culprit and nonculprit coronary arteries in patients with acute ST segment elevation myocardial infarction who were treated with thrombolysis or primary PTCA with stent implantation. Twenty patients were randomized to thrombolysis (with recombinant tissue plasminogen activator) and 24 to primary PTCA with stent implantation within 3 hours of onset of acute ST segment elevation myocardial infarction. Coronary angiography was performed 90-120 minutes after thrombolysis or immediately after PTCA with stent implantation and again at 18-36 hours after intervention in both groups. Patients who failed to achieve thrombolysis in myocardial infarction (TIMI) grade 2 or 3 flow were excluded. The corrected TIMI frame count was used as the index of basal coronary artery flow. Early after intervention the mean corrected TIMI frame count in the culprit coronary artery was significantly lower in the primary PTCA with stent group (27.4 +/- 7.7 frames) than in the thrombolysis group (39.8 +/- 10 frames, p < 0.001). Eight thrombolysis patients (40%) and 20 primary PTCA patients (83%, p < 0.01) achieved TIMI grade 3 flow early after intervention. By 18-36 hours after intervention there were no significant differences in the mean correct TIMI frame count between the thrombolysis and primary PTCA with stent groups. There were no significant differences in the mean corrected TIMI frame count between these two groups in the nonculprit coronary artery, either early after intervention or at 18-36 hours. In successfully reperfused coronary arteries following acute ST segment elevation myocardial infarction, primary angioplasty with stent implantation reestablished TIMI grade 2 or 3 flow faster and more effectively than thrombolysis did.     

Assessment of residual coronary arterial stenosis after thrombolytic therapy during acute myocardial infarction

Maximal myocardial salvage appears to be related to the severity of residual coronary arterial stenosis after thrombolysis. The degree of residual infarct vessel stenosis was assessed in 119 consecutive patients with patent arteries who received streptokinase during acute myocardial infarction. After administration of streptokinase, 99 of 119 patients (83%) had a residual stenosis 70% or more in diameter. Assuming that a residual diameter stenosis of at least 70% is flow limiting, the feasibility for percutaneous transluminal coronary angioplasty (PTCA) was determined by the following criteria: length less than 10 mm, no significant distal narrowing or left main stenosis, and an adequate-sized distal artery. In 81 of 99 patients (82%), arterial anatomy was suitable for PTCA. Thus, after therapy with streptokinase for acute myocardial infarction, most patients have a significant infarct arterial residual stenosis and are candidates for PTCA.     

Angioplasty in total coronary arterial occlusion

Percutaneous transluminal coronary angioplasty (PTCA) was attempted in 67 patients with total coronary arterial occlusion but without associated acute transmural infarction. No patient received concomitant streptokinase therapy. The duration of occlusion was one week or less in 22 patients, one week to one month in 24 patients, one to three months in 13 patients, and more than three months in eight patients. The occluded vessel was the left anterior descending artery in 38 (57%), the right coronary artery in 22 (33%), and the circumflex coronary artery in seven (10%). A steerable system was used in 29 patients whereas a fixed guide wire system was used in 38. Dilation was successful in 44 patients (66%). When a steerable system was used, PTCA was successful in 76% of the patients, compared with 58% when a nonsteerable system was used. The average size of stenosis after dilation was 32%. In the patients with a recent occlusion (one week or less in duration), PTCA was successful in 82%, which was significantly better than in patients with an older occlusion (greater than 12 weeks), in whom dilation was successful in only 25% (p less than 0.01). In patients with an occlusion of one to three months, PTCA was successful in 65%. During a mean follow-up of 1.6 years in the 44 patients with successful dilation, 37 were asymptomatic without angina, although five had required repeat dilation or coronary bypass surgery. In selected patients with symptomatic coronary artery disease and recent coronary occlusion but without associated myocardial infarction, PTCA alone is an effective means of restoring flow. After successful dilation, the majority of patients remain asymptomatic.     

Chest pain after coronary interventional procedures

Chest pain following successful percutaneous coronary interventions is a common problem. Although the development of chest pain after coronary interventions may be of benign character, it is disturbing to patients, relatives and hospital staff. Such pain may be indicative of acute coronary artery closure, coronary artery spasm or myocardial infarction, but may also simply reflect local coronary artery trauma. The distinction between these causes of chest pain is crucial in selecting optimal care. Management of these patients may involve repeat coronary angiography and additional intervention. Commonly, repeat coronary angiography following percutaneous transluminal coronary angioplasty (PTCA) in patients with chest pain demonstrates widely patent lesion sites suggesting that the pain was due to coronary artery spasm, coronary arterial wall stretching or was of non-cardiac origin. As reported by the National Heart, Lung and Blood Institute PTCA Registry, 4.6% of patients after angioplasty have coronary occlusions, 4.8% suffer a myocardial infarction, and 4.2% have coronary spasm. The frequency of chest pain after new device coronary interventions (atherectomy and stenting) seems to be even higher. However, only the minority of patients with post-procedural chest pain have indeed an ischemic event. Therefore, the vast majority of patients have recurrent chest pain without any signs of ischemia. There is some evidence that non-ischemic chest pain after coronary interventions is more common after stent implantation as compared to PTCA (41% vs. 12%). This may be due to the continuous stretching of the arterial wall by the stent as the elastic recoil occurring after PTCA is minimized. In conclusion, chest pain after coronary interventional procedures may potentially be hazardous when due to myocardial ischemia. However, especially after coronary stent placement, cardiologists must consider "stretch pain" due to the overdilation and stretching of the artery caused by the stent in the differential diagnosis. Clinically, it is, therefore, important to recognize that in addition to ischemia-related chest pain other types of chest pain do exist with cardiac origin.     

Reperfusion through balloon catheter to minimize myocardial infarction during the interval between failed percutaneous transluminal coronary angioplasty and emergency coronary artery bypass grafting

Summary A 65-year-old man was admitted with chest pain. A diagnosis of spastic angina was made because of symptoms of recurrent anginal attacks associated with ST-segment elevations in the electrocardiogram. A selective coronary arteriogram revealed a 90% diameter narrowing of the proximal left anterior descending coronary artery (LAD). No angiographically visible collaterals from the right coronary artery to the LAD were observed. The ventriculogram showed normal contraction of the left ventricle with an ejection fraction of 65%. Percutaneous transluminal coronary angioplasty (PTCA) failed resulting in total occlusion of the stenosis. Repeat PTCA at a higher pressure and of longer duration failed to redilate the artery. Reperfusion with the blood from the femoral artery through the balloon catheter, which was used for the PTCA, was carried out until coronary artery bypass grafting (CABG). Blood flow rate of perfusion was approximately 25 ml/min. Reperfusion through the balloon catheter reduced chest pain and ST-segment elevations in the electrocardiogram. The patient tolerated the operative procedure well and his post-operative course was uncomplicated. The interval between the acute occlusion and revascularization by CABG was approximately 4 1/4 h. The ventriculogram taken 56 days after the CABG demonstrated normal contraction of the anterior wall of the left ventricle with an ejection fraction of 63%. Abnormal Q waves did not appear in precordial leads of the electrocardiogram after the surgery. The thallium scintigram showed no perfusion defects.In conclusion, this case suggested that autologous blood reperfusion through balloon cathether would be worth attempting in some cases for minimization of myocardial infarction during the interval between failed PTCA and emergency CABG.     

Spontaneous coronary artery dissection--a case report and review of the literature

Spontaneous coronary artery dissection remains an extremely rare cause of myocardial ischemia and infarction. The clinical picture of spontaneous coronary dissection is often sudden cardiac death or fatal myocardial infarction. This report describes a previously healthy woman who developed spontaneous coronary artery dissection. She presented with sudden onset of chest pain and was found to have evidence of acute inferior wall myocardial infarction. She received streptokinase immediately after admission to the coronary care unit. Coronary angiographic studies revealed a linear dissection involving the proximal and mid segments of the right coronary artery.     

Angioplasty in total coronary artery occlusion

Percutaneous transluminal coronary angioplasty was attempted without streptokinase in 24 patients with total coronary artery occlusion but without acute transmural myocardial infarction. The maximal duration of occlusion was estimated to be 1 week or less in 10 patients, more than 1 to 4 weeks in 6, more than 4 to 12 weeks in 3 and more than 12 weeks in 5. Dilation of the occluded artery was attempted in the left anterior descending coronary artery in 17 patients, in the right coronary artery in 4 and in the circumflex coronary artery in 3. Angioplasty was successful in 13 patients (54%): left anterior descending coronary artery in 59%, right coronary artery in 50% and circumflex coronary artery in 33%. In patients with successful dilation, there was a mean decrease in coronary artery stenosis from 100 to 23%. In the 19 patients whose occlusion was estimated to be of 12 weeks' duration or less, angioplasty was successful in 68%. In the five patients whose occlusion was estimated to be of more than 12 weeks' duration, dilation was not successful in any (p = 0.006). It is concluded that in selected patients with symptomatic coronary artery disease and recent coronary artery occlusion without associated acute myocardial infarction, percutaneous transluminal coronary angioplasty alone may be effective in restoring patency.     

Acute closure during coronary excimer laser angioplasty and conventional balloon dilatation: a comparison of management outcome and prediction

Of 523 consecutive patients undergoing elective percutaneoustransluminal coronary angioplasty (PTCA) and 83 patients treatedwith coronary excimer laser angioplasty (ELCA), 17 (3.3%) hadin-laboratory occlusion following PTCA and 25 (30%)followingELCA; they were enrolled into a prospective study. Successfulmanagement (reopened vessel, patency at repeat angiography within24 h, no death, no myocardial infarction (MI), no emergencybypass surgery) including repeat lasing, subsequent PTCA, useof intracoronary nitroglycerin or streptokinase was achievedin 24 (96%) of the 25 patients with acute occlusion during ELCA.An anterior MI occurred in one patient of the laser group. Repeatballoon dilatation was successfully performed in seven of the17 patients (41%) with acute closure during PTCA. Among the10 patients with persistent occlusion after PTCA, five developeda limited myocardial infarction (35%). One patient requiredemergency CABG, and died peri-operatively. Severe spasm priorto occlusion defined by a new coronary flow depression withoutevidence of dissection or thrombus showed a significant positiveassociation with acute occlusion during ELCA (P =0.0008). Thus, in contrast to occlusion during PTCA, subsequent balloondilatation was successfully performed in the majority of patientswith acute occlusion during ELCA, implying that different underlyingmechanisms are responsible for this complication. In this limitedpatient group, occlusion after excimer laser angioplasty wasmuch more frequent than closure during PTCA, but was infrequentlyassociated with major events such as myocardial infarction ordeath.     

Acute coronary artery occlusion during and after percutaneous transluminal coronary angioplasty. Frequency, prediction, clinical course, management, and follow-up

BACKGROUND. Acute coronary artery occlusion after percutaneous transluminal coronary angioplasty (PTCA) continues to remain a serious complication despite significant improvement in operator performance and technological advancements. This retrospective study was performed to ascertain the frequency, predictive variables, management, and outcome of acute coronary artery occlusion. METHODS AND RESULTS. The study was based on data from 1,423 consecutive patients who underwent an elective coronary angioplasty between January 1986 and December 1988. Acute coronary artery occlusion occurred in 104 patients (7.3%). Acute occlusion developed during the dilatation procedure in 80 patients (5.6%) and within 24 hours after the procedure in 24 patients (1.7%). Four clinical and 14 angiographic variables predictive for acute coronary artery occlusion were analyzed in these 104 patients with a complicated procedure and were compared with those in 104 representative patients with successful attempts. Multivariate analysis found three independent predictive variables: unstable angina, multivessel disease, and complex lesions. The overall clinical outcome after management of acute coronary artery occlusion including immediate repeat dilatation (95 patients), use of intracoronary streptokinase (34 patients), or autoperfusion catheter (12 patients) was successful (reduction of lumen diameter to less than 50%, no death, no myocardial infarction [MI], and no emergency surgery) in 42 patients (40%), was a failure without major complication in four patients (4%), and was a failure with major complication (death, MI, and emergency surgery) in 58 patients (56%). The overall mortality rate was 6% (six patients), the overall MI rate was 36% (37 patients), and emergency bypass surgery was required in 30% of patients (31 patients). At 6 months' follow-up of 42 patients with successful management, recurrent angina pectoris due to restenosis occurred in 10 patients (24%), and a late MI occurred in one patient (3%). At 6 months' follow-up of 56 survivors with unsuccessful management (development of MI or need for emergency bypass surgery), recurrent angina occurred in nine patients (16%), and cardiac death in two patients (4%). However, the majority of patients in both groups were either symptom free or had mild angina pectoris. CONCLUSION. Acute coronary artery occlusion during PTCA is often unpredictable, but its frequency is higher in patients with unstable angina, multivessel disease, and complex lesions. Despite immediate redilatation, use of intracoronary streptokinase, and emergency bypass surgery, PTCA is associated with a high mortality and morbidity.     

Wellens' syndrome and other electrocardiographic changes in a patient with a left anterior descending artery subocclusion associated with a left main coronary artery subocclusion

Changing axis deviation has been reported also during atrial fibrillation or atrial flutter. Changing axis deviation has been also reported during acute myocardial infarction associated with atrial fibrillation too or at the end of atrial fibrillation during acute myocardial infarction. Patients with unstable angina have a higher incidence of left main coronary artery (LMCA) and proximal left anterior descending (LAD) coronary artery disease compared to patients with stable angina pectoris. In 1982, Wellens and colleagues described two electrocardiographic patterns that were predictive of critical narrowing of the proximal LAD artery, and were subsequently termed Wellens' syndrome. The criteria were: a) prior history of chest pain, b) little or no cardiac enzyme elevation, c) no pathologic precordial ST segment elevation, d) no loss of precordial R waves, and e) biphasic T waves in leads V2 and V3, or asymmetric, often deeply inverted T waves in leads V2 and V3. The ECG changes are best recognized outside the episode of anginal pain. Lead aVR and lead v1 ST segment elevation, during chest pain, has been reported in patients with LMCA disease with ST segment depression in leads V3, V4 and V5 (with maximal depression in V4).We present a case of changing axis deviation in a 37-year-old Italian man with a LAD coronary artery subocclusion associated with a LMCA subocclusion. This case focuses attention on the importance of the recognition of the patterns suspected for LAD coronary artery disease or for LMCA disease.     

Use of tissue plasminogen activator in the coronary care unit for acute closure after coronary angioplasty

Coronary angioplasty in a patient ten days following myocardial infarction was complicated by repeated thrombotic occlusion requiring intracoronary streptokinase. Recurrence of chest pain and ST elevations after transfer to the coronary care unit was successfully managed with intravenous tissue plasminogen activator without returning the patient to the catheterization laboratory.     

胸部钝性外伤性急性心肌梗塞2例报告及文献复习

本文报告2例青年于胸部钝性外伤后出现心肌异常Q波和损伤性ST段抬高，其心电图和心肌酶学的演变与典型的急性心肌梗塞（AMI）相同。胸部钝性外伤致AMI的主要机理为冠状动脉内膜扯裂、内膜下出血、血栓形成以及粥样斑块扯裂而导致冠状动脉阻塞，受累最多的是左前降支。由于常伴体表、心脏或其它脏器的挫伤或损伤，全身抗凝或静脉溶栓治疗通常为禁忌。如病人条件允许，可施行冠脉搭桥、PTCA或冠状动脉内溶栓等治疗。     

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.     

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.     

Early occlusion following successful coronary angioplasty: clinical and angiographic observations

To assess clinical and angiographic features of early occlusion after percutaneous transluminal coronary angioplasty (PTCA), 25 successful PTCA procedures (3%) with early occlusion were analyzed from a PTCA population of 917. Twenty patients (80%) had unstable angina, while 12 (48%) had a recent (less than 1 mo) myocardial infarction subtended by the PTCA vessel. All patients received a calcium blocker, aspirin, dipyridamole, and heparin prior to PTCA. In 20 of 25 patients (80%), occlusion occurred in the catheterization laboratory, while five occurred out of laboratory, three within 5 hours and 1 each within 24 and 48 hours. Angiographic features before PTCA included complex lesions (hazy, stained, or ulcerated) in 12 (48%) and intracoronary filling defects in eight patients (32%). Post-PTCA intracoronary filling defects were present in 17 dilated stenoses (68%). Compared to a consecutive control population of 100 patients with similar demographics but without acute occlusion, the frequency of unstable angina, acute myocardial infarction, and filling defects was greater in patients with early occlusion (P less than .001 for all). Intracoronary nitroglycerin was utilized in all patients with reopening in only one (4%), while bypass surgery was performed in five (20%). Intravenous streptokinase was administered to two patients with reperfusion in one. Immediate repeat PTCA was successful in 15 of 17 patients (88%). In summary, recent unstable angina, myocardial infarction, complex lesions or intracoronary filling defects before and particularly after PTCA all suggest an association of clot with early occlusion. Immediate repeat PTCA is frequently successful.     

Role of coronary spasm in the genesis of myocardial infarction: Study of a case treated by isosorbide dinitrate in situ then by transluminal angioplasty

We report the observation of a 62-year-old patient who was admitted for unstable angina. A prolonged chest pain (more than two hours) with a major electrocardiographic lesion in the posterior leads needed an urgent coronary arteriography in order to attempt a recanalization. Antecedents of arteriopathy of the lower limbs with aortobifemoral bypass required an axillary artery right side approach. A selective right coronary opacification showed complete occlusion at the junction of segments 1 and 2. An intracoronary injection of isosorbide dinitrate relieved a coronary spasm and allowed a complete visualization of the right coronary artery. This appeared to be very atherosclerotic with several severe narrowings, and a subocclusive lesion at the site of the initial occlusion. Percutaneous transluminal coronary angioplasties (PTCA) were performed and led to a real ‘restructuring’ of the right coronary artery. The clinical outcome was excellent without recurrent angina pectoris. An angiographic control performed 6 months after PTCA demonstrated the persistence of the coronary recanalization and an evident improvement of the segmental contractility. This report emphasizes the role of coronary spasm in the genesis of my-cardial infarction and shows that PTCA may be performed as a first approach at the acute phase of myocardial infarction; to our knowledge it is the first PTCA performed by an axillary approach at the acute stage of myocardial infarction.     

Changes in high-frequency QRS components are more sensitive than ST-segment deviation for detecting acute coronary artery occlusion

OBJECTIVES: This study describes changes in high-frequency QRS components (HF-QRS) during percutaneous transluminal coronary angioplasty (PTCA) and compares the ability of these changes in HF-QRS and ST-segment deviation in the standard 12-lead electrocardiogram (ECG) to detect acute coronary artery occlusion. BACKGROUND: Previous studies have shown decreased HF-QRS in the frequency range of 150-250 Hz during acute myocardial ischemia. It would be important to know whether the high-frequency analysis could add information to that available from the ST segments in the standard ECG. METHODS: The study population consisted of 52 patients undergoing prolonged balloon occlusion during PTCA. Signal-averaged electrocardiograms (SAECG) were recorded prior to and during the balloon inflation. The HF-QRS were determined within a bandwidth of 150-250 Hz in the preinflation and inflation SAECGs. The ST-segment deviation during inflation was determined in the standard frequency range. RESULTS: The sensitivity for detecting acute coronary artery occlusion was 88% using the high-frequency method. In 71% of the patients there was ST elevation during inflation. If both ST elevation and depression were considered, the sensitivity was 79%. The sensitivity was significantly higher using the high-frequency method, p<0.002, compared with the assessment of ST elevation. CONCLUSIONS: Acute coronary artery occlusion is detected with higher sensitivity using high-frequency QRS analysis compared with conventional assessment of ST segments. This result suggests that analysis of HF-QRS could provide an adjunctive tool with high sensitivity for detecting acute myocardial ischemia.     

Retrograde lysis of coronary artery thrombus by coronary venous streptokinase administration

This study examined whether an occlusive thrombus within a coronary artery can be lysed by streptokinase retroperfusion into the associated regional coronary vein. Experimental coronary artery thrombosis was induced in 15 closed chest dogs by placing a small copper coil at a proximal site of the left anterior descending coronary artery. Total thrombotic obstruction of this artery was verified within 10 to 60 minutes (38.0 +/- 15.8, mean +/- standard deviation) and streptokinase was administered within 94.0 +/- 17.4 minutes from coil insertion at an average rate of 42 IU/kg per minute by one of three modes: 1) intermittent 10 minute direct coronary venous retroinfusion (five dogs); 2) continuous infusion into the pumping circuit of synchronized phased retroperfusion of the great cardiac vein with arterial blood (five dogs); and 3) for comparison, streptokinase administered intravenously (five dogs). The intracoronary thrombus was fully lysed and anterograde reperfusion established within 51.0 +/- 18.7 minutes by intermittent streptokinase retroinfusion, and in 50.0 +/- 6.1 minutes by streptokinase supplemented synchronized retroperfusion (50.5 +/- 13.2 minutes for pooled retrograde coronary venous delivery). Lysis was also induced by systemic streptokinase, but the time to lysis was significantly longer and more variable (131.6 +/- 60.6 minutes) than with retrograde administration (p less than 0.01). The retroperfusion modality appears the preferable technique because it provides early thrombolysis and, at the same time, improves cardiac function and maintains myocardial viability of the jeopardized ischemic zone pending achievement of full reflow. Thus, streptokinase retroperfusion, if promptly instituted, may be a useful complemental nonsurgical treatment of evolving acute myocardial infarction after thrombotic coronary artery occlusion.     

Evaluation of clinical criteria of coronary artery recanalization in acute myocardial infarction

Clinical features of recanalization of infarct-related coronary artery during thrombolytic therapy or emergency PTCA and their correlation with immediate coronary angiography were analysed in 23 patients with acute myocardial infarction (AMI) to evaluate the predictive value of clinical criteria of reperfusion. The coronary angiography was performed before treatment and every 15 to 30 minutes during intravenous (rt-PA) or intracoronary (UK or SK) thrombolysis. Reperfusion was achieved in 16 cases by thrombolysis and in 4 cases by PTCA. The results revealed that in patients with reperfusion chest pain was relieved rapidly at least 70% in a period of 30 minutes, the ST segments fell by 50% or more from their elevated levels during a period of 30 minutes. Transient "paradoxical" increase of ST segment elevation followed by rapid falling was observed in 4 patients. This phenomenon was considered as a reliable marker of reperfusion. The changes in cardiac rhythm and conduction were noticed in 90% of the patients with reperfusion, among them accelerated idioventricular rhythm and disappearance of new-onset AVB and intraventricular conduction defects were useful bedside evidences of reperfusion, and transient significant sinus bradycardia or AVB with or without transient hypotension were useful markers of reperfusion in inferior myocardial infarction. When these clinical criteria were separately used as predictor of infarct-related coronary artery recanalization, the specificity was about 70% to 80%. Using the presence of all 3 criteria, the specificity and predictive value increased to 100% and the sensitivity was 70.6%. The time interval between onset of symptoms and peak CK and CK-MB were significantly shorter in patients with reperfusion than in those without persistent reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)