The relationship between periprocedural myocardial infarction and subsequent target vessel revascularization following percutaneous coronary revascularization: insights from the EPIC trial. Evaluation of IIb/IIIa platelet receptor antagonist 7E3 in Preventing Ischemic Complications.
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OBJECTIVES: We sought to determine whether periprocedural myocardial infarction complicating percutaneous coronary revascularization is associated with subsequent clinical restenosis, as judged by the need for target vessel revascularization. BACKGROUND: Although myocardial enzyme elevation following angioplasty is associated with increased late mortality, its effect on subsequent clinical restenosis, as assessed by the need for late target vessel revascularization (TVR), is unknown. METHODS: Serial myocardial enzyme determinations were performed on 2,099 patients who underwent angioplasty or atherectomy in the Evaluation of IIb/IIIa platelet receptor antagonist 7E3 in Preventing Ischemic Complications (EPIC) trial. Thirty-day survivors were prospectively followed for three years for adverse clinical events including death and need for TVR. RESULTS: Within the study population, periprocedural creatine kinase (CK) elevation was a predictor of late mortality. Among patients with elevated CK, however, a paradoxical decrease in the need for late TVR was present. This relationship became progressively more profound as the magnitude of CK release increased. Late TVR occurred in 29.8% of patients with no CK elevation, 24.8% with CK elevation to >3 times normal, and 16.9% with >10 times elevation (hazard ratio 0.51, 95% CI 0.29, 0.91). CONCLUSIONS: In the EPIC study, patients with periprocedural MI were less likely to develop clinical restenosis as measured by the need for TVR. Mechanistically, although it is unlikely that CK elevation prevents vascular renarrowing per se, myocardial necrosis impairs the clinical manifestation of restenosis, thereby reducing the need for ischemia-driven TVR. This novel finding 1) highlights the potential discordance between angiographic and clinical measures of restenosis, and 2) has implications for clinical trials, as therapies that reduce periprocedural MI may be associated with a perceived excess of restenosis when measured by the need for TVR. (+info)
Intravenous nicorandil can preserve microvascular integrity and myocardial viability in patients with reperfused anterior wall myocardial infarction.
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OBJECTIVES: We assessed whether the intravenous administration of nicorandil, an adenosine triphosphate (ATP)-sensitive K+ channel opener, exerts beneficial effect on microvascular function and functional and clinical outcomes in patients with acute myocardial infarction (AMI). BACKGROUND: Experimental studies documented that ATP-sensitive K+ channel opener exerts cardioprotection after prolonged ischemia. METHODS: We randomly divided 81 patients with a first anterior AMI into two groups, nicorandil (n = 40) and control groups (n = 41). All patients received successful coronary angioplasty within 12 h after the symptom onset and underwent myocardial contrast echcardiography (MCE) with the intracoronary injection of sonicated microbubbles. In the nicorandil group, we injected 4 mg of nicorandil followed by the infusion at 6 mg/h for 24 h and by oral nicorandil (15 mg/day). RESULTS: The improvement in regional left ventricular function, wall motion score and regional wall motion was significantly better in the nicorandil group then in the control group. Intractable congestive heart failure, malignant ventricular arrhythmia and pericardial effusion were more frequently found in the control group than in the nicorandil group (15% vs. 37%, 5% vs. 20% and 8% vs. 37%, p < 0.05, respectively). The frequency of sizable MCE no reflow phenomenon was significantly lower in the nicorandil group than in the control group (15% vs. 33%, p < 0.05). CONCLUSIONS: Intravenous nicorandil in conjunction with coronary angioplasty is associated with better functional and clinical outcomes compared to angioplasty alone in patients with an anterior AMI. Myocardial contrast echocardiography findings imply that an improvement in microvascular function with nicorandil may be attributable to this better outcome. (+info)
Effects of pacing-induced and balloon coronary occlusion ischemia on left atrial function in patients with coronary artery disease.
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OBJECTIVES: The aim of this study was to compare left atrial (LA) function in 16 patients with distal left anterior descending (LAD) and in 16 patients with proximal left circumflex (LCx) coronary artery stenosis at rest and immediately after pacing-induced tachycardia (LAD-pacing [P] and LCx-P) or coronary occlusion (LAD-CO and LCx-CO). BACKGROUND: During left ventricular (LV) ischemia, compensatory augmentation of LA contraction enhances LV filling and performance. The left atrium is supplied predominantly by branches arising from the LCx. Therefore, we hypothesized that one mechanism for the loss of atrial contraction may be ischemic LA dysfunction. METHODS: Left ventricular and LA pressure-area relations were derived from simultaneous double-tip micromanometer pressure recordings and automatic boundary detection echocardiograms. RESULTS: Immediately after pacing or after coronary occlusion, LV end-diastolic pressure, LV relaxation, LA mean pressure and LV stiffness significantly increased in all patients. However, the area of the A loop of the LA pressure-area relation, representing the LA pump function, significantly decreased in groups LCx-P and LCx-CO (from 14+/-3 to 9+/-2, and from 16+/-4 to 9+/-2 mm Hg.cm2, respectively, p < 0.05), whereas it increased in groups LAD-P and LAD-CO (from 12+/-3 to 54+/-10, and from 16+/-3 to 49+/-8 mm Hg.cm2, respectively, p < 0.001). CONCLUSIONS: In patients with LAD stenosis, LV supply or demand ischemia is associated with enhanced LA pump function. However, in patients with proximal LCx stenosis who develop the same type and degree of ischemia, LA branches might have been affected, rendering the LA ischemic and unable to increase its booster pump function. (+info)
Prognostic value of dobutamine stress echocardiography in predicting cardiac events in patients with known or suspected coronary artery disease.
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OBJECTIVES: The study sought to determine the utility of dobutamine stress echocardiography (DSE) in predicting cardiac events in the year after testing. BACKGROUND: Increasingly, DSE has been applied to risk stratification of patients. METHODS: Medical records of 1,183 consecutive patients who underwent DSE were reviewed. The cardiac events that occurred during the 12 months after DSE were tabulated: myocardial infarction (MI), cardiac death, percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass surgery (CABG). Patient exclusions included organ transplant receipt or evaluation, recent PTCA, noncardiac death, and lack of follow-up. A positive stress echocardiogram (SE) was defined as new or worsened wall-motion abnormalities (WMAs) consistent with ischemia during DSE. Classification and regression tree (CART) analysis identified variables that best predicted future cardiac events. RESULTS: The average age was 68+/-12 years, with 338 women and 220 men. The overall cardiac event rate was 34% if SE was positive, and 10% if it was negative. The event rates for MI and death were 10% and 8%, respectively, if SE was positive, and 3% and 3%, respectively, if SE was negative. If an ischemic electrocardiogram (ECG) and a positive SE were present, the overall event rate was 42%, versus a 7% rate when ECG and SE were negative for ischemia. Rest WMA was the most useful variable in predicting future cardiac events using CART: 25% of patients with and 6% without a rest WMA had an event. Other important variables were a dobutamine EF <52.5%, a positive SE, an ischemic ECG response, history of hypertension and age. CONCLUSIONS: A positive SE provides useful prognostic information that is enhanced by also considering rest-wall motion, stress ECG response, and dobutamine EF. (+info)
Percutaneous transluminal coronary angioplasty, alone or in combination with urokinase therapy, during acute myocardial infarction.
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To investigate the effect of pre-treatment of a thrombus with a low dose of urokinase on establishing patency in a persistent infarct-related artery (IRA) during direct percutaneous coronary angioplasty (PTCA), the frequency of acute restenosis during direct PTCA, alone, or in combination with the intracoronary administration of urokinase, was examined in a consecutive nonrandomized series of patients with acute myocardial infarction (AMI). Two hundred and seventy-two successful PTCA patients (residual stenosis <50%) were divided into 2 groups: 88 patients received pre-treatment with intracoronary urokinase following PTCA (combination group); 184 received only direct PTCA without thrombolytic therapy (PTCA group). In the present study, after achievement of a residual stenosis of less than 50%, IRA was visualized every 15 min to assess the frequency of acute restenosis, which was defined as an acute progression of IRA with more than 75% restenosis after initially successful PTCA. In the patients with a large coronary thrombus, the frequency (times) of acute restenosis was significantly lower in the combination group than in the PTCA group (0.98+/-0.19 vs 2.92+/-0.32, p<0.0001). On the other hand, in the patients with a small coronary thrombus, the frequency of acute restenosis showed no difference in either group. The present study indicates that in patients with AMI, PTCA combined with pre-treatment of a low dose of urokinase is much more effective than PTCA alone, especially for those patients who have a large coronary thrombus. (+info)
Primary percutaneous transluminal coronary angioplasty performed for acute myocardial infarction in a patient with idiopathic thrombocytopenic purpura.
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A 72-year-old female with idiopathic thrombocytopenic purpura (ITP) complained of severe chest pain. Electrocardiography showed ST-segment depression and negative T wave in I, aVL and V4-6. Following a diagnosis of acute myocardial infarction (AMI), urgent coronary angiography revealed 99% organic stenosis with delayed flow in the proximal segment and 50% in the middle segment of the left anterior descending artery (LAD). Subsequently, percutaneous transluminal coronary angioplasty (PTCA) for the stenosis in the proximal LAD was performed. In the coronary care unit, her blood pressure dropped. Hematomas around the puncture sites were observed and the platelet count was 28,000/mm3. After transfusion, electrocardiography revealed ST-segment elevation in I, aVL and V1-6. Urgent recatheterization disclosed total occlusion in the middle segment of the LAD. Subsequently, PTCA was performed successfully. Then, intravenous immunoglobulin increased the platelet count and the bleeding tendency disappeared. A case of AMI with ITP is rare. The present case suggests that primary PTCA can be a useful therapeutic strategy, but careful attention must be paid to hemostasis and to managing the platelet count. (+info)
Long-term prognosis in achieving a 'stent'like' result from balloon angioplasty: 8 years' clinical outcome.
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This study evaluated the long-term prognosis of optimal 'stent-like' results, suboptimal results and failure of balloon angioplasty. The clinical data of 108 patients were examined during 8 years following balloon angioplasty. Based on the angiographic results, the patients were divided into 3 groups: Group A (n=59), <25% residual stenosis (ie, optimal stent-like result); Group B (n=43), 26-50% residual stenosis or large dissection (ie, suboptimal result); and Group C (n=6), >50% residual stenosis or stenosis could not be crossed (ie, failed angioplasty). Restenosis occurred in 20 of 43 patients (46.5%) in Group B, but only in 18 of 59 patients (30.4%) in Group A. Achieving stent-like results following balloon angioplasty significantly reduced the incidence of restenosis. Kaplan-Meier curves at 8 years demonstrated a survival rate without serious cardiac events of 83% in patients with stent-like results compared with 58% in those with suboptimal results and 17% in those with failed balloon angioplasty. In conclusion, the major finding of this study is that achieving stent-like results following balloon angioplasty reduces the incidence of restenosis, and 8-year survival without serious cardiac events after balloon angioplasty is significantly better in patients who have a stent-like result. (+info)
Detecting myocardial salvage after primary PTCA: early myocardial contrast echocardiography versus delayed sestamibi perfusion imaging.
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The extent of myocardial salvage after primary percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction (AMI) is variable and cannot be predicted on the basis of either vessel patency or early regional wall motion assessment. The aim of this study was to evaluate the reliability of microvascular integrity, as shown by myocardial contrast echocardiography (MCE), as an indicator of tissue salvage and a predictor of late functional recovery, and to compare MCE with the quantification of tracer activity in sestamibi perfusion imaging. METHODS: Twenty-six patients with AMI who received successful treatment with primary PTCA were examined with MCE during cardiac catheterization immediately before and after vessel recanalization. Myocardial contrast effect was scored as 0 (absent), 0.5 (partial) or 1 (normal). Wall motion was assessed by two-dimensional echocardiography on admission and 1 mo later with a 16-segment model and 4-point score. Resting sestamibi SPECT was collected within 1 wk after AMI. The risk area was defined by MCE as the sum of the segments with no perfusion (score 0) before PTCA. Myocardial viability was defined by MCE as an increase in contrast score in the same segments after PTCA and by sestamibi SPECT as a preserved tracer activity (>60% of peak activity). The functional recovery after 1 mo detected by two-dimensional echocardiography was the reference standard for viability. RESULTS: A total of 50 segments showed perfusion defects before PTCA (risk area). Immediately after PTCA, the MCE score increased in 44 of 50 segments, whereas sestamibi SPECT showed preserved activity in 22 of 50 segments. After 1 mo, the wall motion score decreased in 22 of 50 segments (viable segments) and was unchanged in the remaining 28 segments. Thus, MCE showed a sensitivity of 91% and a specificity of 14% in detecting viable myocardium, whereas sestamibi SPECT showed a lower sensitivity (68%) but a significantly higher specificity (75%; P < 0.00001). The positive predictive values were 45% and 68% for MCE and SPECT (P < 0.005), respectively, and the negative predictive values were 67% and 71%, respectively. On a patient basis, SPECT was more specific (79% versus 21%; P < 0.01) and showed a higher overall predictive accuracy (88% versus 50%; P < 0.01) than MCE. CONCLUSION: The demonstration of microvascular integrity by MCE performed immediately after primary PTCA has a limited diagnostic value in predicting salvaged myocardium. Conversely, tracer activity quantification in resting sestamibi SPECT performed in a later stage is confirmed to be a reliable approach for recognizing myocardial stunning and predicting functional recovery. (+info)