The efficacy and limitation of rescue coronary angioplasty for acute myocardial infarction]

Eighty one patients with acute transmural anterior myocardial infarction admitted to our hospital, from January, 1987 to February, 1991, were included in the present study. In 62 cases, reperfusion therapy was performed within 12 hours from the onset of chest pain. Forty nine patients underwent intracoronary thrombolysis, and in 16 patients (group RA) with failed thrombolysis (TIMI less than or equal to 1) percutaneous transluminal coronary angioplasty (PTCA) was performed as a "rescue" procedure. We studied the efficacy and limitation of rescue PTCA compared with direct PTCA (group DA, n = 13), intracoronary thrombolysis (group CT, n = 33) and conservative therapy without the above interventions (group N, n = 19). Initial reperfusion rate of intracoronary thrombolysis was 53% which was lower than group RA (88%) and group DA (100%) (p less than 0.05, p less than 0.01, respectively). Residual stenosis of infarct-related artery in the chronic phase (mean 28 +/- 7 days after initial intervention) in group CT was higher than group RA and group DA (p less than 0.01, p less than 0.01, respectively). LVEDVI in intervention groups (group CT, group RA, and group DA) were similar and significantly smaller than group N (p less than 0.05, p less than 0.05, and p less than 0.01, respectively). Ejection Fraction (EF) in intervention groups were significantly higher than group N. Regional wall motion of infarcted area in group CT and group DA were significantly better than group N (p less than 0.01, p less than 0.01, respectively). However, RWM in group RA was not significantly different compared with group N.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of transmural myocardial perfusion by ultra-harmonic myocardial contrast echocardiography in reperfused acute myocardial infarction.

BACKGROUND: The transmural distribution of myocardial perfusion is important for predicting the contractile reverse of an infarcted wall in reperfused acute myocardial infarction (AMI). Evaluating transmural myocardial perfusion by myocardial contrast echocardiography (MCE) could predict the long-term recovery of left ventricular (LV) function. METHODS AND RESULTS: The study group comprised 20 consecutive patients with a first-episode anterior AMI with total occlusion of the proximal left anterior descending artery, who underwent successful percutaneous coronary intervention within 24 h of onset. MCE was performed on the 15th day after the onset, using ultraharmonic gray-scale imaging with intermittent end-systolic triggering every 4 beats or every 6 beats. Regions of interest were placed over both the endocardial and epicardial region at the mid-septal level. Regional wall motion (RWM) of the infarcted anterior wall and global LV function were assessed by 2-dimensional echocardiography and left ventriculography in both the acute and chronic phase. The transmural distribution of myocardial perfusion by MCE demonstrated a significant relation with RWM score index (r = 0.75, p = 0.0004). Recovery of RWM and LV ejection fraction (LVEF) at 6 months after reperfusion was significantly greater in the group with good perfusion of the epicardium according to MCE than in the poor perfusion group [RWM (SD/cord); -1.23+/-0.91 vs -3.51+/-0.84, p = 0.001, LVEF (%); 63.8+/-10.4 vs 47.0+/-3.4, p = 0.04]. CONCLUSIONS: Assessing the transmural distribution of myocardial perfusion by MCE can predict the long-term recovery of LV function after a reperfused AMI.     

Management and outcomes of patients transferred for rescue coronary angioplasty in acute myocardial infarction.

BACKGROUND: Rescue coronary angioplasty (PTCA), though recommended by the guidelines, is not regularly performed after failed lysis in patients with ST-elevation acute myocardial infarction (AMI), and data from large contemporary studies are not available. The outcomes of a recent series of consecutive patients in our Center are presented. METHODS: Between August 2000 and November 2003, 270 patients with AMI < 12 hours were referred to our cath lab for emergency PTCA: 117 (43%) for rescue PTCA after failed lysis, and 153 for primary or facilitated PTCA. The baseline, procedural and outcome data of all patients were prospectively collected, analyzed on an "intention-to-treat" basis and compared. Cineangiographic data were reviewed by three angiographers who were unaware of the clinical data. RESULTS: No significant differences were found between rescue PTCA and primary/facilitated PTCA patients as to: age, female gender, diabetes, hypertension, previous AMI, time from pain onset to the first emergency room admission, heart rate at admission, systolic blood pressure, number of leads with ST-segment elevation, total ST-segment deviation, collateral flow to the infarct-related artery, initial TIMI 2-3 flow, and three-vessel disease. Patients with rescue PTCA, as compared to primary/facilitated PTCA, had a longer time from pain onset to the cath lab (336 +/- 196 vs 229 +/- 155 min, p = 0.0001) and more frequently had an anterior AMI (52 vs 38%, p = 0.027), a higher Killip class (1.5 +/- 0.98 vs 1.26 +/- 0.7, p = 0.02), shock (11 vs 5%, p = 0.073), and intra-aortic balloon pump use (17 vs 8%, p = 0.048); fewer patients were in Killip class 1 (74 vs 85%, p = 0.043). PTCA was performed immediately in 78 vs 95% of patients (p = 0.0001); 8 vs 3 patients had PTCA of the infarct-related artery and 8 vs 1 had bypass surgery later during hospitalization. Patients with rescue PTCA, as compared to primary/facilitated PTCA, had a final TIMI 3 flow in 62 vs 76% of cases (p = 0.017), > or = 70% ST-segment resolution in 36 vs 50% (p = 0.086), and both of the latter in 24 vs 45% (p = 0.006); the overall hospital mortality was 12 vs 6.5%, and 5.8 vs 3.4% when patients in shock on admission were not considered; reinfarction and stroke occurred in 0.9 vs 1.3% and in 2.6 vs 0% of the patients respectively. CONCLUSIONS: Due to referral, rescue PTCA patients were admitted to the cath lab later after the onset of infarction, and had a higher risk profile, as compared to primary/facilitated PTCA patients; both recanalization and reperfusion were less satisfactory, as were the outcomes. Thrombolysis is often ineffective but, as long as it remains a widespread treatment, efforts should be made to improve reperfusion and survival in these patients, possibly by an earlier referral for rescue PTCA.     

Changes in Left Ventricular Function After Coronary Recanalization by Percutaneous Transluminal Coronary Angioplasty (PTCA)

Forty-six patients (21 with stable angina and 25 with chronic myocardial infarction, 37 men) with a total chronic proximal coronary occlusion and collateral vessels to the distal part of the occluded artery (30 LAD, 10 RCA and 6 CX properly distributed in both groups) were studied angiographically before and 2 to 8 months (mean 6) after balloon angioplasty. The patients were divided in six subgroups: A) Angina pectoris no matter the result of recanalization (n = 21); B) Myocardial infarction no matter the result of recanalization (n = 25); C) Angina pectoris with successful recanalization and open coronary (O.C.) > 50% at follow-up (n = 13); D) Angina pectoris with unsuccessful recanalization and/or restenosis or closed coronary (C.C.) at follow-up (n = 8); E) Myocardial infarction with successful recanalization and O.C. > 50% at follow-up (n = 8); F) Myocardial infarction with unsuccessful recanalization and/or restenosis or C.C. at follow-up (n = 17). No subgroup showed statistical differences (p > 0.05) in LVEDP before (B) and at follow-up (FU). On the other hand, several measurements were statistically different in the subgroup A at B and at FU: Ejection fraction (EF) [57.3 +/- 12.3 and 64.2 +/- 19.4%; p = 0.02]; Regional wall motion (RWM) measured in the region of the affected coronary [18.7 +/- 9.6 and 23.6 +/- 11.8%; p = 0.05]; Minimal wall motion (MWM) measured in the site of lesser parietal movement [14.3 +/- 13.1 and 25.8 +/- 26.2%; p = 0.02]. In the subgroup C the following differences were observed: EF [58.4 +/- 12.3 and 69.0 +/- 12.4%; p = 0.003]; RWM [16.3 +/- 8.4 and 25.4 +/- 8.2%; p = 0.005]; MWM [14.7 +/- 15.1 and 27.9 +/- 18.0%; p = 0.0001]. In the other considered subgroups we did not reach significant differences (p > 0.05) in these measurements. We conclude that recanalization of a chronic coronary occlusion improves left ventricular contractile function in the presence of viable myocardium and that MSF is the most sensitive among the studied variables to separate anginal patients from the patients without viable myocardium after successful recanalization.     

Efficacy of low-dose mutant tissue-type plasminogen activator followed by planned rescue percutaneous transluminal coronary angioplasty as reperfusion therapy for acute myocardial infarction

OBJECTIVES: The efficacy of injection of a low-dose mutant tissue-type plasminogen activator (mt-PA), monteplase, followed by planned rescue percutaneous transluminal coronary angioplasty (PTCA) was compared with that of primary PTCA. METHODS: A total of 164 patients with acute myocardial infarction within 12 hr from onset were randomly assigned to a treatment with 80 x 10(4) U bolus of monteplase (Group M) or no administration (Group P) by the envelope method, followed by immediate angiography with angioplasty in patients with Thombolysis in Myocardial Infarction (TIMI) flow grade 0, 1 or 2. RESULTS: There were no differences in baseline characteristics between the two groups. Initial angiography showed a higher reperfusion rate (TIMI 2 + 3: 21% + 38% vs 13% + 9%, p < 0.001) and the median time to TIMI 3 was shorter (63 vs 78 min, p < 0.005) in Group M than in Group P, but the final TIMI 3 rate was similar (93% vs 96%). Peak creatine kinase was lower, and predischarge left ventricular ejection fraction measured in 70% of all patients was higher (59 +/- 9% vs 54 +/- 14%, p = 0.02) in Group M than in Group P. Recurrent ischemia with ST elevation occurred in three patients in Group M, but death, re-acute myocardial infarction or stroke did not occur in either group and the rate of bleeding complication was similar (4.9% vs 3.7%). PTCA was performed less frequently in Group M, but medical expenses were comparable in both groups. CONCLUSIONS: Low-dose mt-PA followed by rescue PTCA is effective for early recanalization and preservation of left ventricular function without increases in bleeding complications or medical expenses. These results suggest that low-dose mt-PA should be given to all patients with acute myocardial infarction who are scheduled to undergo primary PTCA.     

Rescue angioplasty during myocardial infarction has a beneficial effect on mortality: a tenable hypothesis.

HYPOTHESIS: Rescue percutaneous transluminal coronary angioplasty (PTCA) reduces mortality during myocardial infarction. OBJECTIVE: To determine if PTCA after failed thrombolytic therapy results in reduced mortality. DESIGN: Twenty-eight patients with a persistently occluded infarct artery following thrombolytic therapy more than 3 h after symptom onset were randomized to rescue PTCA (n = 16) or conservative treatment (n = 12) as part of a prospective randomized trial of reperfusion therapy during myocardial infarction in 184 patients. Hospital mortality was assessed in these groups as well as in the 177 patients with known infarct artery status after initial attempts at reperfusion. MAIN RESULTS: There was one death among the 16 patients in the rescue PTCA group versus four deaths in the 12 patients treated conservatively (P = 0.13). Moreover, the death in the rescue PTCA group occurred in one of three patients in whom the procedure failed. Mortality in the entire study group was 10.3% (19 of 184); 4.2% (six of 142) in patients in whom patency was achieved after thrombolysis and/or PTCA and 34.3% (12 of 35) in those in whom reperfusion was not achieved (P less than 0.001). In patients with anterior myocardial infarction, mortality was 6.7% (four of 60) in those with reperfusion and 47.1% (eight of 17) in those with a persistently occluded artery (P less than 0.001). In patients with inferior myocardial infarction, 2.4% (two of 82) with reperfusion and 22.2% (four of 18) with a persistently occluded artery died (P less than 0.01). CONCLUSIONS: Although the number of patients in the randomized groups was small, the trend toward a lower mortality after rescue PTCA supports the hypothesis that rescue PTCA may be beneficial. The mortality results in relation to presence or absence of reperfusion from the entire study population underscores the importance of achieving patency during myocardial infarction.     

Comparison of left ventricular function and contractile reserve after successful recanalization by thrombolysis versus rescue percutaneous transluminal coronary angioplasty for acute myocardial infarction

To determine how coronary reperfusion affects rest and exercise ventricular function after acute myocardial infarction (AMI), 63 patients with a patent infarct artery after intravenous thrombolytic therapy (lysis) were compared with 27 patients who failed thrombolysis but had successful acute recanalization by percutaneous transluminal coronary angioplasty (PTCA) as a "rescue" procedure. Contrast ventriculography was performed acutely and on day 7. Resting radionuclide ventriculography was performed at 24 hours and repeated with exercise on day 30. There were no differences in global ejection fraction (EF) between the 2 groups during acute contrast ventriculography. However, by 24 hours, the EF had deteriorated in the rescue group (40 +/- 17 vs 49 +/- 11% in the lysis group, p less than or equal to 0.05). No improvement occurred in either group on day 7. By day 30, an improvement in resting radionuclide EF 5.9 +/- 1.9% occurred in rescue patients and the difference between rescue and lysis groups was no longer significant (46 +/- 14 vs 50 +/- 11%, p = 0.12). A normal (greater than or equal to 5%) increase in EF with exercise occurred in 64%, with either normal or exercise-enhanced regional wall motion present in 67% of patients. A significant increase in EF occurred within the rescue group, from 46 +/- 14% at rest to 50 +/- 15% at peak exercise (p less than or equal to 0.0005). The EF increased with exercise from 50 +/- 11 to 58 +/- 15% in the lysis group (p less than or equal to 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Percutaneous transluminal coronary angioplasty for treatment of acute myocardial infarction: comparison with percutaneous transluminal coronary recanalization

Percutaneous transluminal coronary angioplasty (PTCA) was evaluated as a means of reperfusion of the infarct-related coronary artery, and the results were compared with those of percutaneous transluminal coronary recanalization (PTCR). There were no difference in sex, age, infarct location and time from the onset to start of treatment between 135 patients with evolving acute myocardial infarction treated with PTCA (PTCA group) and 113 patients treated with PTCR alone (PTCR group). Fifty-nine patients in the PTCA group underwent PTCA following PTCR; the remaining 76 patients were without prior PTCR. Successful PTCA, defined as a 20% or more reduction in percent luminal stenosis diameter, was achieved in 123 (90%) of the 135 patients in the PTCA group. The reperfusion rate was 93% in the PTCA group and 77% in the PTCR group (p less than 0.01). Residual stenosis immediately after the treatment was 30 +/- 13% in the PTCA group and 70 +/- 16% in the PTCR group (p less than 0.01). In the PTCA group, three cases developed serious complications which were associated with angioplasty: coronary perforation, side branch occlusion resulting in cardiogenic shock and exacerbation of cardiogenic shock. The latter two patients died, however, there was no difference in hospital mortality rate: 6% in the PTCA group versus 11% in the PTCR group. At follow-up angiography performed four weeks after admission, reocclusion of the successfully recanalized arteries was observed in 3% of the PTCA group and in 14% of the PTCR group (p less than 0.01). Regional wall motion was evaluated by left ventriculography using a wall motion score system which consisted of six grades; from normal counted as 0, to dyskinesis counted as 5. There was no difference in the wall motion score between the successful PTCA group and the successful PTCR group (2.6 +/- 1.4 versus 2.8 +/- 1.4), but the scores of both groups were better than those of the non-recanalized group (3.4 +/- 1.0: p less than 0.01). In conclusion, PTCA and PTCR have the same effect on hospital mortality rate and regional wall motion, but PTCA has a higher reperfusion rate and a lower reocclusion rate than does PTCR. Although PTCA has a potential disadvantage inducing serious complications, it appears to be a useful treatment for acute myocardial infarction.     

Clinical significance of acute-phase brain natriuretic peptide in acute myocardial infarction treated with direct coronary angioplasty

OBJECTIVES: To investigate the relationship between brain natriuretic peptide (BNP) plasma concentration levels and the clinical course, mortality and success of left ventricular remodeling by direct percutaneous coronary intervention (PCI) in patients with acute myocardial infarction. METHODS: One hundred thirty consecutive first-acute myocardial infarction patients were successfully reperfused by direct PCI. BNP plasma concentration levels were assessed at 24 hr from onset, and patients were divided into the high (> or = 290 pg/ml) plasma BNP group (H-BNP group; n = 65) or low (< 290 pg/ml) plasma BNP subset (L-BNP group; n = 65). Left ventriculography was performed in both the acute (following reperfusion therapy) and chronic (20 +/- 8 days after onset) stages to evaluate left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume index (LVEDVI) and regional wall motion (RWM). Differences between the parameters at the two stages (chronic stage--acute stage) were expressed as delta LVEF, delta LVEDVI, and delta RWM. RESULTS: There were significantly more major complications in the H-BNP group than in the L-BNP group. There was significantly higher mortality in the H-BNP group (p < 0.01). Multivariate analysis identified only BNP plasma concentration as an independent predictor of mortality (p < 0.05). There were no significant differences in left ventricular function in the acute stage between the groups, but LVEF, LVEDVI, and RWM were all significantly worse in the chronic stage in the H-BNP group compared with the L-BNP group. Moreover, delta LVEF (p < 0.001), delta LVEDVI (p < 0.05), and delta RWM (p < 0.01) were also significantly worse in the H-BNP group. CONCLUSIONS: Early-phase BNP plasma concentrations after successful PCI in patients with acute myocardial infarction may be correlated closely with major complications, and may be of prognostic importance. BNP plasma concentration may also be an indicator of left ventricular remodelling.     

Efficacy of percutaneous transluminal coronary angioplasty in patients with acute myocardial infarction--comparison with intracoronary thrombolysis

We retrospectively compared the efficacy of percutaneous transluminal coronary angioplasty (PTCA) and intracoronary thrombolysis (ICT) in patients with acute myocardial infarction (AMI). The ICT group consisted of 62 consecutive patients who underwent ICT before the introduction of PTCA for AMI and who were considered to be candidates for PTCA based on review of their cine-films. The PTCA group consisted of 92 consecutive patients who underwent PTCA thereafter. The reperfusion rate was significantly higher in the PTCA group than in the ICT group (92.4% vs 71.4%, p less than 0.01) and the residual stenosis was significantly lower in the former. Furthermore, the incidences of reinfarction and post-infarction angina were significantly lower in the former than in the latter (3.3% vs 12.9%, p less than 0.05 and 6.5% vs 29.0%, p less than 0.001 respectively). Although the degree of improvement in left ventricular function was influenced by the result of reperfusion, it was not affected by the reperfusion method. Therefore, PTCA did not improve left ventricular function more than ICT unless ICT alone failed to achieve reperfusion.     

Persistent ST-segment elevation after primary stenting for acute myocardial infarction: its relation to left ventricular recovery

BACKGROUND: Early restoration of coronary artery patency in acute myocardial infarction (AMI) has been linked to improvement in survival. However, early recanalization of an occluded epicardial coronary artery by either thrombolytic agents or percutaneous transluminal coronary angioplasty (PTCA) does not necessarily lead to left ventricular (LV) function recovery. HYPOTHESIS: The aim of this study was to evaluate the relation between persistent ST elevation shortly after primary stenting for acute myocardial infarction (AMI) and LV recovery. METHODS: Thirty-one patients with primary stenting for AMI were prospectively enrolled. To evaluate the extent of microvascular injury, serial ST-segment analysis on a 12-lead electrocardiogram recording just before and at the end of the coronary intervention was performed. Persistent ST-segment elevation (Persistent Group, n = 11) was defined as > or = 50% of peak ST elevation and resolution (Resolution Group, n = 20) was defined as < 50% of peak ST elevation. Echocardiography was performed on Day 1 and 3 months after primary stenting. RESULTS: At 3 months, infarct zone wall-motion score index (WMSI, 2.1 +/- 0.6 vs. 2.7 +/- 0.3, p < 0.05) was smaller in the Resolution Group than in the Persistent Group, whereas wall motion recovery index (RI, 0.4 +/- 0.3 vs. 0.1 +/- 0.2, p < 0.05) and ejection fraction (58 +/- 5 vs. 43 +/- 10%, p < 0.05) were larger in the Resolution Group than in the Persistent Group. The extent of persistent ST elevation (% ST) shortly after successful recanalization of the infarct-related artery was significantly related to RI at 3 months (r = -0.4, p < 0.05). However, time to reperfusion was not related to RI at 3 months. There was also significant correlation between corrected TIMI frame count and %ST (r = 0.4, p < 0.05). CONCLUSIONS: Persistent ST-segment elevation shortly after successful recanalization (> or = 50% of the peak value), as a marker of impaired microvascular reperfusion, predicts poor LV recovery 3 months after primary stenting for AMI.     

Course and prognostic implications of QT interval and QT interval variability after primary coronary angioplasty in acute myocardial infarction

OBJECTIVES: The aim of this study was to determine the influence of early reperfusion on the course of QT interval and QT interval variability in patients undergoing primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) and its prognostic implications on major arrhythmic events during one-year follow-up. BACKGROUND: Although early coronary artery recanalization by primary angioplasty is an established therapy in AMI, a substantial number of patients is still threatened by malignant arrhythmias even after early successful reperfusion, which may be caused by an inhomogeneity of ventricular repolarization despite reperfusion. METHOD: Temporal fluctuations of ventricular repolarization were studied prospectively in 97 consecutive patients with a first AMI by measurements of QT interval and QT interval variability during and after successful PTCA (Thrombolysis in Myocardial Infarction flow grades 2 and 3). Continuous beat-to-beat QT interval measurement was performed from 24-h Holter monitoring, which was initiated at admission before PTCA. RESULTS: Reperfusion caused a significant continuous increase of mean RR interval (738 +/- 98 to 808.5 +/- 121 ms; p < 0.001) and a significant decrease of parameters of QT interval (QTc: 440 +/- 32 to 416.5 +/- 37ms; p < 0.001) and QT interval variability (QTcSD: 27.5 +/- 3 to 24.9 +/- 6 ms; p < 0.001) in the majority of patients. However, in patients with major arrhythmic events at the one-year follow-up (sudden cardiac death, ventricular fibrillation or sustained ventricular tachycardia, n = 15), parameters of QT interval remained unaltered after successful reperfusion (QTc: 447.3 +/- 41 to 432.9 +/- 45 ms, p = NS; QTcSD: 35.1 +/- 13.4 to 29.0 +/- 9.1 ms, p = NS). CONCLUSIONS: Reduction of QT interval and QT interval variability after timely reperfusion of the infarct-related artery may be a previously unreported beneficial mechanism of primary PTCA in AMI, indicating successful reperfusion.     

Experimental study on myocardial salvage by coronary thrombolysis and mechanical recanalization

Salvage of the ischemic myocardium by coronary thrombolysis and mechanical recanalization (simulated angioplasty) was studied in a canine experimental model of acute myocardial infarction induced by coronary occlusive thrombus at the left anterior descending coronary artery. Forty-four open-chest dogs divided into three groups were studied. Group I (n = 15, control group) was observed for 6 hours following the onset of infarct. In group II (n = 14, thrombolysis group), thrombolysis was obtained by intravenous administration of urokinase 2 hours after the onset of infarct. In group III (n = 15, mechanical recanalization group), simulated angioplasty was performed 2 hours after infarct. Coronary reperfusion was continued for 4 hours in groups II and III. The areas of left ventricular risk and infarct were measured by double staining methods with Evans blue dye and triphenyl tetrazolium hydrochloride. There were no significant differences in control blood flow and risk area in the three groups. Myocardial infarct area/risk area was 65 +/- 3% in group I, 45 +/- 1% in group II, and 35 +/- 2% in group III (group I vs II, p less than 0.001; group II vs III, p less than 0.001). Restored coronary blood flow in the left anterior descending artery was 8 +/- 1 ml/min in group II and 14 +/- 1 ml/min in group III (p less than 0.001). The data suggest that coronary mechanical recanalization is more effective than thrombolysis in salvaging the ischemic myocardium in the early phase of myocardial infarction, most probably because coronary blood flow is better restored by mechanical recanalization.     

Improvement of chronic regionally impaired myocardial function immediately after coronary angioplasty]

The effect of PTCA on chronically impaired, regional wall motion was studied in 40 patients with stable angina and stenoses in the left anterior descending artery. Left-ventricular angiograms were obtained before, 15 min after PTCA and, additionally, in eight patients 15 +/- 5 weeks after PTCA. Left-ventricular ejection fraction and regional myocardial function were assessed by the centerline method. Patients with no (n = 18) or non-Q-wave (n = 12) infarction were compared to patients with Q-wave infarction (n = 10). After PTCA, ejection fraction increased from 54 +/- 8% to 59 +/- 8% (p less than 0.05) and regional function improved significantly (maximal standard deviation before PTCA: 2.8 +/- 0.8; after PTCA: 1.9 +/- 0.9- segments below the first standard deviation before PTCA: 31 +/- 16; after PTCA: 19 +/- 17). The improvements were found in patients with no or non-Q-wave infarction. The benefit on regional function was unchanged at follow-up. Conclusions: PTCA reduced chronic regional myocardial dysfunction in 78% of the patients with stable angina within 15 min. Reversible myocardial dysfunction is most likely related to hibernating myocardium.     

Postinfarctional remodeling: increased dye intensity in the myocardial risk area after angioplasty of infarct-related coronary artery is associated with reduction of ventricular volumes

OBJECTIVES: We sought to evaluate if angiographic dye videointensity of the risk area during percutaneous transluminal coronary angioplasty (PTCA) of the infarct-related artery (IRA) relates to remodeling. BACKGROUND: Poor reflow after myocardial infarction (MI) predicts worse ventricular remodeling. METHODS: Fifty-three patients with a first anterior MI and isolated disease of the left anterior descending (LAD), who underwent "primary" (n = 14), "rescue" (n = 7) or "late" (after 10 +/- 4 days, n = 32) PTCA, were retrospectively selected. In 10 patients prospectively collected, we assessed Doppler flow velocities and Doppler flow reserve (DFR), relating them to the videointensity technique. Coronary stenosis and TIMI flow were determined, and echocardiographic volumes (end-diastolic and end-systolic volume indexes) and regional asynergy were computed before hospital discharge (baseline) and at six months. Assuming higher peak videointensity reflects greater myocardial blood volume, a 1- to 5-point (poor-optimal) perfusion scale was devised. RESULTS: The correlation of Doppler peak velocity and DFR with videointensity was significant (r = 0.58, p = 0.007 and r = 0.71, p < 0.001, respectively). Patients were subdivided into group A (increased videointensity post-PTCA > or = 1.5 points, n = 29) and group B (unchanged videointensity, n = 24). Analysis of variance showed a time-group interaction for end-diastolic volume index (-4.6 +/- 23% vs. +22 +/- 22%, p = 0.003) and end-systolic volume index (-3.05 +/- 11.1% vs. +4.1 +/- 12.5%, p = 0.027). There was no interaction for changes in LAD stenosis (p = 0.39) and TIMI flow after PTCA (p = 0.27), or regional asynergy at six months (p = 0.31). CONCLUSIONS: Angiographic dye videointensity in the risk area correlates with Doppler peak velocity and DFR, and its increase after PTCA of IRA has a limiting effect on ventricular volumes, independent of coronary stenosis resolution, changes in Thrombolysis In Myocardial Infarction (TIMI) flow or extent of regional asynergy.     

Value of percutaneous transluminal coronary angioplasty after unsuccessful intravenous streptokinase therapy in acute myocardial infarction

The effect of sequential high-dose intravenous streptokinase (SK) (1.5 million units) followed by emergency percutaneous transluminal coronary angioplasty (PTCA) on preserving left ventricular function was assessed prospectively in 34 patients with acute myocardial infarction (AMI). Intravenous SK therapy was initiated 2.6 +/- 1.3 hours (mean +/- standard deviation) after the onset of chest pain. Urgent coronary angiography showed persistent total occlusion in 13 patients, significant diameter stenosis (70 to 99%) in 18 patients and a widely patent artery (less than 50% stenosis) in 3 patients. Emergency PTCA was performed in 29 patients 5.0 +/- 2.1 hours after symptom onset. Successful recanalization was achieved in 33 of the 34 patients (97%) treated with sequential therapy. Repeat contrast ventriculograms recorded 7 to 10 days after intervention in 23 patients showed that the left ventricular ejection fraction increased from 53 +/- 12% to 59 +/- 13% (area-length method, p less than 0.002). Regional wall motion of the infarcted segments improved from -2.7 +/- 1.1 to -1.5 +/- 1.7 SD/chord (centerline method, p less than 0.003). In the subgroup of patients with an occluded artery on initial angiography (group A, n = 10), both global left ventricular ejection fraction (49 +/- 12% vs 59 +/- 12%, p less than 0.002) and regional wall motion (-3.2 +/- 1.0 vs -1.9 +/- 1.7 SD/chord, p less than 0.002) improved significantly. In contrast, no significant improvement was seen in patients with a patent artery on initial angiography (n = 13). Thus, sequential intravenous SK and emergency PTCA is efficacious in achieving coronary reperfusion and in improving both global and regional left ventricular function.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intraaortic balloon pumping as the postangioplasty strategy in acute myocardial infarction.

To assess the usefulness of intraaortic balloon pumping (IABP) in acute myocardial infarction (AMI), 114 patients with anterior AMI undergoing emergency percutaneous transluminal coronary angioplasty (PTCA) for total occlusion of the left anterior descending artery were studied. After successful PTCA 66 patients were treated with conventional therapy (group I), and 48 patients were treated with IABP for 25 +/- 8 hours (group II). The reocclusion rate was significantly lower in group II (2.4% vs 17.7% p less than 0.05). An increase in ejection fraction in group II compared with group I was marginally significant (4.5 +/- 12.2% vs 9.2 +/- 13.0%, p = 0.08). Vascular complications occurred in two patients, but there were no deaths from IABP. These results suggest that after successful PTCA for acute myocardial infarction, IABP prevents reocclusion and may add strength to reperfusion in the improvement of left ventricular function.     

Polymorphonuclear neutrophils in myocardial ischemia and reperfusion injury. Influence of coronary intervention?

Circulating polymorphonuclear neutrophils (PMNs) are known to contribute to the pathophysiology of myocardial ischemia and reperfusion injury. The present study was designed to examine whether the duration of ischemia in myocardial infarction, the type of coronary intervention (angioplasty vs. angioplasty plus stenting) and duration of the procedure itself modulate the inflammatory responses of PMNs. METHODS AND RESULTS: In patients with acute myocardial infarction (AMI; n = 20) neutrophil beta-2-integrin Mac-1 (CD11b/CD18) and L-selectin (CD62L) were determined at different time points before and after PTCA or PTCA plus stenting. After PTCA alone but not after PTCA plus stenting a significant rise in Mac-1 (136 +/- 43%) was demonstrated. This elevation decreased after 60 minutes if the duration of the recanalization procedure was shorter than 30 minutes but remained elevated after longer interventions. After delayed intervention a significant and more pronounced increase of Mac-1 (142 +/- 37%) was observed, while early intervention prevented this increase. After PTCA alone or delayed intervention a significant shedding of L-selectin (77 +/- 20%; 77 +/- 23%) was demonstrated. Early intervention or PTCA plus stenting caused no significant changes in L-selectin. CONCLUSIONS: It is concluded that PMN activation is attenuated by early and short intervention as well as by stenting. Induction of PMN activation might contribute to the superior outcome following stenting and early intervention compared to conventional PTCA in particular when performed delayed.     

Clinical significance of pressure measurement in the infarct-related coronary artery in acute myocardial infarction: evaluation of variables predicting recovery of left ventricular function in the convalescent stage

Early reperfusion and good antegrade flow are essential in restoring better regional left ventricular function in acute myocardial infarction, but they do not always correlate with the extent of recovery. This study evaluated coronary circulation using the new "pressure wire" technique to measure the direct pressure of the coronary circulation including antegrade and collateral flow before and after reperfusion in patients with acute myocardial infarction, and to clarify the influence of these variables on recovery of left ventricular function in the convalescent stage. Fifty six consecutive patients with first acute myocardial infarction underwent percutaneous transluminal coronary angioplasty(PTCA) for totally occluded or severely narrowed infarct-related lesion and evaluation of coronary circulation using pressure wire. Left ventriculography was analyzed at 1 month after the onset in 41 patients. Treatment variables including reperfusion time, reperfusion modality, Thrombolysis in Myocardial Infarction(TIMI) grade after PTCA, and pressure wire variables were compared with parameters of left ventricular function. Reperfusion time was not related to regional wall motion evaluated by the SD chord of left ventriculography in the infarcted zone. Pressure wire measurements showed a correlation between fractional flow reserve measured after PTCA and infarcted regional wall motion(r = 0.558, p < 0.01). Patients with infarct-related lesion in the right coronary artery showed the magnitude of left ventricular regional wall motion was related to fractional collateral flow reserve(maxQc/Qn) during PTCA(r = 0.768, p < 0.05), but no such relationship was observed in patients with infarct-related lesion in the left anterior descending artery. Fractional flow reserve measured after PTCA varied widely in patients with the same TIMI flow grade, so did not vary with it. The pressure wire technique enables assessment of the collateral circulation distal to infarct-related lesion quantitatively before reperfusion in patients with acute myocardial infarction. The fractional flow reserve derived by coronary pressure after reperfusion was significantly related to the recovery of regional wall motion in the infarcted area in the convalescent stage. The fractional flow reserve after reperfusion with PTCA is a better parameter than TIMI flow grade for predicting recovery of regional left ventricular function after myocardial infarction.     

Serial assessment of right ventricular function in the acute and convalescent stages after successful reperfusion: relationship to infarct-related coronary artery

OBJECTIVES: To elucidate the relationship between the infarct-related coronary artery and the right ventricular function before and after successful recanalization. METHODS: Hemodynamics and right ventricular function were measured using a REF-1 thermodilution catheter before and shortly after recanalization and during the convalescent stage in 35 patients, 17 with anteroseptal and 18 with inferior acute myocardial infarction. RESULTS: Pulmonary arterial pressure significantly decreased in both anteroseptal and inferior myocardial infarction patients after recanalization. Right ventricular volume index in patients with anteroseptal myocardial infarction increased after recanalization, but again decreased during convalescence. The right ventricle became enlarged in patients with inferior myocardial infarction to maintain the right ventricular stroke volume constant. Right ventricular ejection fraction (RVEF) did not significantly change in patients with inferior myocardial infarction during convalescence (38 +/- 13%, 38 +/- 13%, 46 +/- 9%), whereas RVEF in patients with anteroseptal myocardial infarction temporarily decreased after recanalization, and then increased during convalescence (37 +/- 10%, 31 +/- 12%, 41 +/- 7%). Patients with inferior myocardial infarction were divided into two groups, patients with increased RVEF (n = 6) and decreased RVEF (n = 12) shortly after recanalization. Patients with increased RVEF showed significantly improved RVEF during convalescence (49 +/- 7% vs 37 +/- 6%, p < 0.05). The increase in RVEF shortly after recanalization in patients with inferior myocardial infarction was an independent factor for predicting RVEF during convalescence. CONCLUSIONS: Patients with anteroseptal myocardial infarction showed a different pattern of change in the right ventricular function during the acute and convalescent stages. An early change in RVEF in patients with inferior myocardial infarction can predict RVEF in the convalescent stage.