Implications for patient triage from survival and left ventricular functional recovery analyses in 500 patients treated with coronary angioplasty for acute myocardial infarction

The in-hospital course of 500 consecutive patients treated with coronary angioplasty for acute myocardial infarction was reviewed in relation to their clinical and angiographic presentation and angioplasty outcome to determine which patients benefit most from successful angioplasty in this setting. Patient age was 56 +/- 11 years (mean +/- SD) and 78% were men; 46% had anterior myocardial infarction, 49% received concomitant intravenous thrombolytic therapy, left ventricular ejection fraction was 47 +/- 11% and median time to angioplasty was 4.7 h (range 1 to 24). Angioplasty was successful in 78% of patients and partially successful in 7% of patients; the overall in-hospital mortality rate was 10.2%. Multivariate analysis found six independent correlates (p less than 0.05) of in-hospital mortality: left ventricular ejection fraction less than or equal to 30%, lack of postangioplasty infarct artery patency, age greater than 65 years, recurrent ischemia after successful angioplasty, emergency bypass surgery and arterial pressure on admission to the catheterization laboratory less than 100 mm Hg. After consideration of these predictors of survival in multivariate analyses, angioplasty success still was independently correlated with improved in-hospital survival for patients with cardiogenic shock (p = 0.002) and anterior myocardial infarction (p = 0.007). A trend toward an independent beneficial effect of successful angioplasty on survival was also noted in patients with inferior wall infarction and precordial ST segment depression (p = 0.063) and for all patients who were hypotensive on admission to the catheterization laboratory, regardless of the infarct site (p = 0.057).(ABSTRACT TRUNCATED AT 250 WORDS)     

Prognostic significance of location and type of myocardial infarction: independent adverse outcome associated with anterior location

To determine the relative prognostic significance of location (anterior or inferior) and type (Q wave or non-Q wave) of infarction, the hospital course and follow-up outcome (mean duration 30.8 months) of 471 patients with a first infarction were analyzed. Analyses were performed grouping the patients according to infarct location (anterior, n = 253; inferior, n = 218), infarct type (Q wave, n = 323; non-Q wave, n = 148), and both location and type (inferior non-Q wave, n = 85; inferior Q wave, n = 133; anterior non-Q wave, n = 63; and anterior Q wave, n = 190). Patients with anterior infarction had a substantially worse in-hospital and follow-up clinical course compared with those with inferior infarction, evidenced by a larger infarct size (21.2 versus 14.9 g Eq/m2 creatine kinase, MB fraction [MB CK], p less than 0.001), lower admission left ventricular ejection fraction (38.1 versus 55.3%, p less than 0.001) and higher incidence of heart failure (40.7 versus 14.7%, p less than 0.001), serious ventricular ectopic activity (70.2 versus 58.9%, p less than 0.05), in-hospital death (11.9 versus 2.8%, p less than 0.001) and total cumulative cardiac mortality (27 versus 11%, p less than 0.001). Patients with Q wave infarction similarly experienced a worse in-hospital course compared with patients with non-Q wave infarction, evidenced by a larger infarct size (20.7 versus 12.7 MB CK g Eq/m2, p less than 0.001), lower admission left ventricular ejection fraction (43.7 versus 50.6%, p less than 0.001), and a higher incidence of heart failure (31.9 versus 21.6%, p less than 0.05) and in-hospital death (9.3 versus 4.1% p less than 0.05). However, there was no increased rate of reinfarction or mortality in hospital survivors with non-Q wave infarction compared with those with Q wave infarction, and total cardiac mortality was similar (16 versus 21%, p = NS). To evaluate the role of infarct location and type independent of infarct size, patients were grouped according to quartile of infarct size, and outcome was reanalyzed within each group. Patients with anterior infarction demonstrated a lower left ventricular ejection fraction on admission and after 10 days than did patients with inferior infarction, even after adjustment for infarct size, as well as a higher incidence of congestive heart failure and cumulative cardiac mortality.(ABSTRACT TRUNCATED AT 400 WORDS)     

Coronary angioplasty as primary therapy for acute myocardial infarction 6 to 48 hours after symptom onset: report of an initial experience

Recent randomized trials in acute myocardial infarction suggest that infarct size reduction need not be achieved for intravenous streptokinase to improve patient survival. If this is the case, attempts to achieve late revascularization may be justified. To assess the results of late primary coronary angioplasty performed in the setting of acute myocardial infarction, the clinical and angiographic data as well as hospital outcome of 139 consecutive patients treated with coronary angioplasty without prior thrombolytic therapy 6 to 48 h after the onset of chest pain (late group) were compared with those of 117 patients treated with primary angioplasty less than 6 h after the onset of chest pain (early group); time to angioplasty was assessed as a covariate of survival. In the 139 patients treated greater than or equal to 6 h after the onset of chest pain, the mean age (+/- SD) was 57 +/- 12 years and the median time to angioplasty was 15 h; 61% had multivessel disease, 14% were in cardiogenic shock and the mean left ventricular ejection fraction was 44 +/- 12%. Angioplasty was successful (final diameter stenosis less than 70% and Thrombolysis in Myocardial Infarction [TIMI] flow grade greater than or equal to 2) in 78% of patients. Successful angioplasty was associated with a 5.5% in-hospital mortality rate, whereas unsuccessful angioplasty was associated with a 43% hospital mortality rate (p less than 0.001). Multivariate testing in all patients identified four independent predictors of in-hospital death: cardiogenic shock (p less than 0.001), unsuccessful angioplasty (p = 0.001), ejection fraction less than or equal to 30% (p = 0.002) and patient age (p = 0.004).(ABSTRACT TRUNCATED AT 250 WORDS)     

Right ventricular involvement in myocardial infarction and cardiogenic shock

CONTEXT: Right ventricular involvement in acute myocardial infarction and cardiogenic shock has received little attention by clinicians and researchers, although its pathophysiology, clinical presentation, and natural history are distinctly different from those of left ventricular infarction and associated cardiogenic shock. Right ventricular shock has important therapeutic implications for the management of patients, which need to be recognised. STARTING POINT: Investigators at the SHOCK Registry (Alice Jacobs and colleagues, J Am Coll Cardiol 2003; 341: 1273-79) evaluated 49 patients with cardiogenic shock predominantly due to right ventricular infarction and compared them with 884 patients with cardiogenic shock and predominantly left ventricular failure. Perhaps surprisingly, these investigators found that the in-hospital mortality of patients with right ventricular shock was not significantly lower than that of patients with left ventricular shock (53% vs 61%, p=0.296), despite the fact that patients with right ventricular shock were younger, with a lower prevalence of previous infarctions, fewer anterior infarct locations, and less multivessel disease. There was a shorter median time between index infarction and diagnosis of shock in patients with right ventricular shock. In multivariate analysis, right ventricular shock was not an independent predictor of lower in-hospital mortality. WHERE NEXT? The unexpectedly high mortality of patients with cardiogenic shock due to predominantly right ventricular infarction challenges the general notion that right ventricular involvement in myocardial infarction has only little relevance for patient's outcome. Therefore, more attention should be given to the detection of right ventricular involvement in acute myocardial infarction and particularly in cardiogenic shock. If right ventricular shock is diagnosed, urgent reperfusion of the infarct related artery and appropriate circulatory support are required.     

Late clinical outcome in patients with early ventricular fibrillation after myocardial infarction

Whether ventricular fibrillation occurring within 48 h after acute myocardial infarction is associated with particular clinical features and poor prognosis, especially in patients with anterior myocardial infarction, is still debated. Therefore, clinical variables and in-hospital and 1 year mortality rates were analyzed in 2,088 patients, aged 18 to 95 years (mean +/- SD 64 +/- 12), admitted to the hospital with acute myocardial infarction between 1979 and mid 1984. One hundred forty-seven patients (7%) had at least one episode of ventricular fibrillation occurring within 48 h of hospital admission. Of these, 25% died during their initial hospitalization compared with 13% of patients without early ventricular fibrillation (p less than 0.001). In greater than 50% of patients with early ventricular fibrillation, the immediate cause of death was left ventricular failure or cardiogenic shock. In contrast, the 1 year mortality rate after hospital discharge was not significantly greater in patients with than in those without early ventricular fibrillation (15 versus 11%, respectively), particularly in the subgroup of patients with anterior myocardial infarction in which the mortality rate tended to be lower in patients with early ventricular fibrillation (8 versus 14%, respectively). Similar mortality results were found when only primary (not associated with left ventricular failure) ventricular fibrillation was analyzed. The left ventricular ejection fraction and the incidence of complex ventricular arrhythmias from 24 h ambulatory electrocardiographic monitoring obtained at hospital discharge were not different in survivors with or without early ventricular fibrillation (0.45 +/- 0.13 versus 0.49 +/- 0.14 and 41 versus 41%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

Coronary perfusion during acute myocardial infarction with a combined therapy of coronary angioplasty and high-dose intravenous streptokinase

Two hundred and sixteen patients with acute myocardial infarction were treated with immediate infusion of high-dose (1.5 million units) intravenous streptokinase followed by emergency coronary angioplasty. The infarct lesion was crossed and dilated in 99% and persistent coronary perfusion after the procedure was achieved in 90% (including 3% with significant residual stenosis). Total in-hospital mortality was 12%. Multivariable analysis showed a higher hospital mortality with cardiogenic shock (41% vs 5% without shock), older age, lower left ventricular ejection fraction, and female sex. Final patency of the infarct-related vessel was determined by follow-up in-hospital cardiac catheterization. Coronary reocclusion occurred in 11% (symptomatic in 7%, treated with emergency angioplasty or bypass surgery; silent in 4%, treated medically). Of the surviving patients with successful initial establishment of infarct vessel patency, 94% were discharged from the hospital with an open infarct artery or a bypass graft to the infarct vessel. There was significant improvement in both ejection fraction (44% to 49%; p less than .0001) and regional wall motion in the infarct zone (-3.0 SD to -2.4 SD; p less than .0001) among patients with persistent coronary perfusion and insignificant residual stenosis at the time of the follow-up cardiac catheterization. Thus, a treatment strategy for acute myocardial infarction that includes immediate administration of streptokinase followed by emergency coronary angioplasty, and coronary bypass surgery when necessary, results in a high rate of early and sustained patency of the infarct-related vessel.     

Prophylactic intraaortic balloon pumping preserves left ventricular systolic function in acute anterior myocardial infarction without cardiogenic shock

OBJECTIVES: Left ventricular function and prognosis were evaluated in patients with acute myocardial infarction who underwent primary percutaneous coronary intervention supported by intraaortic balloon pumping. METHODS: Fifty-eight consecutive patients with first acute myocardial infarction were treated between July 1999 and April 2006. Twenty-five had cardiogenic shock on admission, whereas 33 did not. Patients with anterior acute myocardial infarction without cardiogenic shock were divided into the prophylactic intraaortic balloon pumping group (Group 1; n=17) and the rescue intraaortic balloon pumping group (Group 2; n=9). RESULTS: Thirty-day in-hospital mortality was 52% in cardiogenic shock patients, and 3% in non-shock patients. Baseline characteristics of non-shock anterior acute myocardial infarction were similar including Thrombolysis in Myocardial Infarction (TIMI) risk scores (5.1 and 5.0) in the two groups. However, average left ventricular ejection fraction in the convalescent stage was superior in Group 1 (48.7% vs. 37.8%, p = 0.03). Thirty-day in-hospital mortality was 0% in Group 1 and 11% in Group 2 (p = 0.34). Cox's hazard ratio in Group 2 to Group 1 was 2.38 (95% confidence intrerval; 0.84-11.1, p = 0.09) in terms of the subsequent major cardiac events. CONCLUSIONS: Prophylactic use of intraaortic balloon pumping starting prior to primary percutaneous coronary intervention preserves the convalescent left ventricular systolic function in patients with high risk for anticipated cardiac events after anterior acute myocardial infarction without cardiogenic shock.     

Relationship between serum total cholesterol, infarct size, and early clinical outcome following acute myocardial infarction.

Strategies designed to decrease coronary heart disease (CHD) associated morbidity and mortality have focused primarily on established risk factors, including hypercholesterolemia, systemic hypertension, and cigarette smoking. Indeed, primary and secondary intervention trials have provided evidence for cholesterol lowering as an efficient method of CHD risk reduction. To test the hypothesis that serum total cholesterol influences the clinical outcome following acute myocardial infarction, infarct size, left ventricular ejection fraction, infarct-related vessel patency, and in-hospital cardiac events were determined in 106 consecutive patients given thrombolytic therapy within 5 h of symptom onset. Cumulative 48-hour creatine kinase (CK) release, peak CK, and calculated infarct size did not differ significantly between patients with an admitting serum total cholesterol level less than 200 mg/dl (group 1) and those with a cholesterol level greater than 250 mg/dl (group 2). Total cholesterol did not correlate with either cumulative CK release, peak CK, infarct size, vessel patency, or left ventricular ejection fraction. The vessel patency correlated inversely with cumulative CK release (r = -0.27; p = 0.03) and directly with left ventricular ejection fraction (r = 0.24; p = 0.03). The incidence of in-hospital cardiac events including recurrent infarction, congestive heart failure, and death was 6.9, 13.9, and 2.6%, respectively, and did not differ significantly between patient groups. Thus, although serum total cholesterol has been shown to influence CHD incidence, morbidity, and overall mortality, the findings of our study suggest that it does not impact directly on infarct size, left ventricular function, or in-hospital clinical outcome among patients sustaining acute myocardial infarction.     

Timing and mechanism of in-hospital and late death after primary coronary angioplasty during acute myocardial infarction

The effect of early myocardial reperfusion on patterns of death after acute myocardial infarction (AMI) is unknown. Thus, the mechanism and timing of in-hospital and late deaths among a group of 614 patients treated with coronary angioplasty without antecedent thrombolytic therapy for AMI were determined. Death occurred in 49 patients (8%) before hospital discharge. Four patients died in the catheterization laboratory. Death was due to cardiogenic shock in 22 patients, acute vessel reclosure in 5 patients, was sudden in 8 patients and followed elective coronary artery bypass surgery in 8 patients. Cardiac rupture was observed in only 2 patients after failed infarct angioplasty, and did not occur among the 574 patients with successful infarct reperfusion. Intracranial hemorrhage did not occur. Multivariate predictors of in-hospital death included failed infarct angioplasty, cardiogenic shock, 3-vessel coronary artery disease and age greater than or equal to 70 years. During a follow-up period of 32 +/- 21 months (range 1 to 87), 55 patients died. The cause of death was cardiac in 36 patients, including an arrhythmic death in 23 patients and was due to circulatory failure in 13 others. One patient died of reinfarction due to late reclosure of the infarct artery. Actuarial survival curves demonstrated overall survival after hospital discharge of 95 and 87% at 1 and 4 years, respectively. Freedom from cardiac death at 1 and 4 years was 96 and 92%. Multivariate predictors of late death included 3-vessel disease, a baseline ejection fraction of less than or equal to 40%, age greater than 70 years and female gender.(ABSTRACT TRUNCATED AT 250 WORDS)     

Left ventricular function in acute myocardial infarction: assessment by nuclear angiography

Left ventricular function was assessed in 38 patients two to six days after acute myocardial infarction using nuclear angiocardiography and the following parameters were measured: Left ventricular end-diastolic (LVEDV) and end-systolic volumes (LVESV), ejection fraction (LVEF), indices of left ventricular filling and emptying, right ventricular ejection fraction and ejection rate. Their clinical significance was assessed by their relationship to the patients site and size of infarction, functional capacity, morbidity and mortality. The most sensitive indices of depressed left ventricular function were the EF and ESV. Thus, function was preserved in patients with a small inferior infarction (LVEF = 0.57 +/- 0.07, LVESV = 69 +/- 14 ml) and in Killip Class I (LVEF = 0.48 +/- 0.13, LVESV = 80 +/- 20 ml). Function was disturbed most in patients with extensive anterior infarction (LVEF = 0.18 +/- 0.12, LVESV = 131 +/- 46 ml), Killip Class IV (LVEF = 0.13 +/- 0.07, LVESV = 160 +/- 35 ml), cardiogenic shock (LVEF = 0.14 +/- 0.07, LVESV = 160 +/- 35 ml), pulmonary edema (LVEF = 0.11 +/- 0.06, LVESV = 166 +/- 25 ml) and pulmonary capillary wedge pressure greater than 20 mm Hg (LVEF = 0.14 +/- 0.07, LVESV = 160 +/- 33 ml). Previous infarction was associated with LV dilatation and a greater LVEDV. A lower ejection fraction signified a large infarct and poor left ventricular function. If the ejection fraction was less than 0.15, the patients were unlikely to leave the hospital alive, or if less than 0.25, they were left with poor residual ventricular function and either had significant cardiac failure or high late mortality. Nuclear angiocardiography was a simple method of predicting the clinical pattern and prognosis in each patient and emphasized the importance of limiting infarct size in acute myocardial infarction.     

Mortality prognostic factors of cardiogenic shock complicating an acute myocardial infarction and treated by percutaneous coronary intervention

OBJECTIVE: To determine the in-hospital prognosis and late outcome of cardiogenic shock complicating acute myocardial infarction treated by early (< 24 hours) percutaneous coronary intervention (PCI). METHODS: Retrospective monocentric study of a consecutive cohort of patients undergoing early PCI (< 24 heures) for cardiogenic shock complicating acute myocardial infarction from 1994 to 2004. RESULTS: The cohort included 175 patients (mean age = 65 +/- 14 years, 68% male). A successful PCI was obtained in 69% of patients. The in-hospital mortality was 43%. Independent risk factors associated with an increased mortality were: absence of TIMI three flow (P < 0.0001), absence of smoking (P < 0.009) and the need for mechanical ventilation (P < 0.002). Nor stent use or anti GP IIb/IIa infusions were predictors of a better outcome. At hospital discharge, mean left ventricular ejection fraction (LVEF) was 38 +/- 12%. Kaplan-Meier estimate of survival was 63% for in-hospital survivors (maximum follow-up = 9 years). Independent predictors of an impaired long-term outcome were: a LVEF < 0.3 (P < 0.028) and 3-vessel disease on coronary angiography (P < 0.004). CONCLUSION: In-hospital mortality of patients suffering cardiogenic shock complicating acute myocardial infarction and treated by PCI remains high despite PCI improvement. The long-term survival appears, however, to be better than that of patients with coronary artery disease and low LVEF.     

Six-year survival after coronary thrombolysis and early revascularization for acute myocardial infarction.

Six-year follow-up was conducted in a consecutive series of 192 patients receiving thrombolytic therapy for acute myocardial infarction (AMI) with ST-segment elevation. Cardiac catheterization was performed within a day, and patients with an open infarct artery routinely had early revascularization: 99 (67%) underwent coronary bypass surgery and 18 (12%) coronary angioplasty. With this treatment strategy, 6-year cardiac mortality was 14.5%, 6% (12 patients) in hospital and 9% (16 patients) for survivors of hospitalization. Multivariate analysis showed that predictors of cardiac death among survivors of hospitalization were a closed infarct artery at catheterization (p less than 0.01), diabetes (p less than 0.01) and anterior myocardial infarction (p = 0.01). A subset of 146 patients underwent radionuclide angiography before hospital discharge; for them, predictors of mortality were a closed infarct artery at catheterization (p less than 0.01), anterior wall AMI (p = 0.02), and Killip class III to IV on admission (p less than 0.06). Left ventricular ejection fraction was not a significant predictor of mortality for this subset of patients.     

Results of primary angioplasty for acute myocardial infarction in patients with multivessel coronary artery disease

The influence of multivessel coronary artery disease on the outcome of reperfusion therapy for myocardial infarction has not been fully characterized. Direct coronary angioplasty without antecedent thrombolytic therapy was performed during evolving myocardial infarction in 285 patients with multivessel coronary artery disease at 5.2 +/- 4.2 h after the onset of chest pain. Two vessel disease was present in 163 patients (57%) and three vessel disease in 122 (43%). An anterior infarct was present in 123 patients (43%), cardiogenic shock in 33 (12%) and age greater than or equal to 70 years in 59 (21%). Angioplasty of the infarct-related vessel was successful in 256 patients (90%), including 92% with two vessel and 88% with three vessel disease (p = NS). Emergency bypass surgery was needed in six patients (2%). In-hospital death occurred in 33 patients (12%), including 13 with two vessel and 20 with three vessel disease (p less than 0.05). The mortality rate was only 4% in the subgroup of 101 patients who met entry criteria for thrombolytic trials. The in-hospital mortality rate was 45% in patients in shock and 7% in patients not in shock (p less than 0.01). Logistic regression analysis identified shock and age greater than or equal to 70 years as independently associated with in-hospital death. In 135 patients who underwent predischarge left ventriculography, global ejection fraction increased from 50% to 57% (p less than 0.001) and regional wall motion in the infarct zone improved in 59% of patients. Follow-up data were available in 251 patients (99%) at a mean of 35 +/- 19 months.(ABSTRACT TRUNCATED AT 250 WORDS)     

Benefit of coronary reperfusion before intervention on outcomes after primary angioplasty for acute myocardial infarction

Primary percutaneous transluminal coronary angioplasty has become the preferred reperfusion strategy for acute myocardial infarction in most institutions with interventional facilities and experienced operators. The benefit of establishing coronary reperfusion, with or without pharmacologic therapy, before primary angioplasty has not been established. Consecutive patients (n = 1,490) with acute myocardial infarction treated with aspirin and heparin followed by primary percutaneous transluminal coronary angioplasty were followed for 13 years. Follow-up angiography was obtained in 737 patients at 7.7 months. Thrombolysis In Myocardial Infarction (TIMI) 2 to 3 flow in the infarct artery at initial angiography was present in 18.3% of patients, and TIMI 0 to 1 flow in 81.7% of patients. Baseline variables were similar between the 2 groups, except patients with initial TIMI 2 to 3 flow had significantly less cardiogenic shock (1.7% vs 9.4%, p <0.0001) and a lower incidence of depressed ejection fraction <40% (12.6% vs 19.9%, p = 0.007). Procedural success was better in patients with initial TIMI 2 to 3 flow (97.4% vs 93.8%, p = 0.02), and catheterization laboratory events were less frequent. Patients with initial TIMI 2 to 3 flow had lower peak creatine kinase values (1,328 vs 2,790 IU/L, p <0.0001), higher acute ejection fraction (54.3% vs 51.6%, p = 0.05), higher late ejection fraction (59.2% vs 54.9%, p = 0.004), and lower 30-day mortality (4.8% vs 8.9%, p = 0.02). These data indicate that when reperfusion occurs before primary angioplasty, outcomes are strikingly better with less cardiogenic shock, improved procedural outcomes, smaller infarct size, better preservation of left ventricular function, and reduced mortality. This should encourage new strategies to establish reperfusion before "primary" angioplasty with "catheterization laboratory friendly" platelet inhibitors and/or low-dose thrombolytic drugs.     

Prognostic implications of an early peak in plasma MB creatine kinase in patients with acute myocardial infarction

To determine the prognostic implications of an early peak in plasma MB creatine kinase (MB CK) in patients with acute myocardial infarction who were not treated with an acute intervention, 342 patients with myocardial infarction confirmed by MB CK were retrospectively studied. The patients were classified into those with an early peak MB CK (less than or equal to 15 hours after the onset of symptoms, n = 84) and those with a late peak MB CK (greater than 15 hours after the onset of symptoms, n = 258). Patients with an early peak MB CK were slightly older, were more frequently female and had a higher incidence of prior myocardial infarction, congestive heart failure and arrhythmias compared with patients with a late peak MB CK. Patients with an early peak MB CK more frequently presented with ST segment depression (23 versus 11%, p less than 0.01), with anterior location of ischemia or infarction (71 versus 52%, p less than 0.01) and with a lower mean left ventricular ejection fraction (41.4 versus 47.4%, p less than 0.01). Despite more extensive left ventricular dysfunction at initial presentation, patients with an early peak MB CK had a smaller mean MB CK infarct size index (12.6 versus 18.9 g-Eq/m2, p less than 0.01), with no difference in the incidence of in-hospital complications, including death. The early left ventricular dysfunction improved in the patients with an early peak MB CK, evidenced by a 4.5% increase in ejection fraction from admission to 10 days after infarction, whereas the ejection fraction did not improve in patients with a late peak MB CK. However, the patients with an early peaking MB CK had myocardium in jeopardy as reflected by a higher incidence of ST segment depression and a decrement in the global left ventricular ejection fraction with exercise. The 4 year life table estimate for the rate of recurrent myocardial infarction after hospital discharge was higher in patients with an early peak MB CK (33 versus 22%, p less than 0.05), with an even more striking difference in the 4 year estimate for the rate of fatal recurrent infarction (20 versus 8%, p less than 0.001). The 4 year mortality estimate was markedly higher in hospital survivors with an early peak MB CK than in those with a late peak (47 versus 19%, p less than 0.0001) and, even after adjustment for differences in baseline characteristics, the residual excess mortality in those with an early peak was still significant (p less than 0.02).(ABSTRACT TRUNCATED AT 400 WORDS)     

Determinants of in-hospital death in left main coronary artery myocardial infarction complicated by cardiogenic shock

BACKGROUND: Acute myocardial infarction (AMI) due to left main coronary artery disease is associated with significantly elevated morbidity and mortality. The aim of this study was to identify the predictors of in-hospital death from left main AMI complicated by cardiogenic shock. METHODS: Clinical record review identified a total of 25 cases of left main AMI with cardiogenic shock. Patients' background characteristics, laboratory data, and angiographic findings were analyzed according to the in-hospital mortality. RESULTS: In this patient subset, in-hospital mortality (60%) was associated with a history of hypertension (p=0.02) and a higher heart rate (p=0.02). Furthermore, in-hospital mortality was also associated with a complete right bundle branch block (CRBBB) pattern in the admission ECG (p=0.01) and low HCO(3)(-) (p=0.0004). In stepwise logistic regression analysis, a CRBBB pattern (OR 48.59, 95% CI 1.34-1768.10, p=0.03) and low HCO(3)(-) (OR 0.62, 95% CI 0.40-0.94, p=0.02) were found to be independent predictors of mortality. CONCLUSIONS: Left main AMI with cardiogenic shock was associated with high in-hospital mortality. A CRBBB pattern in the ECG on admission and a low HCO(3)(-) concentration were significant independent predictors of in-hospital death.     

Differences in left ventricular function between anterior and inferior myocardial infarction of equivalent enzymatic size

The reasons for the poorer prognosis of anterior versus inferior myocardial infarction of equivalent enzymatic size remain uncertain. We investigated whether there are differences in left ventricular function between patients with anterior and inferior infarctions of equivalent enzymatic size to account for their differing outcomes. Clinical, serum enzyme, and electrocardiographic data were prospectively recorded in a consecutive series of patients less than 70 years of age with their first myocardial infarction. At 29 +/- 6 days following infarction, ejection fraction and left ventricular wall motion were assessed by gated heart scintigraphy and functional capacity by treadmill exercise testing in 19 patients with anterior and in 23 patients with inferior myocardial infarction. Peak creatine kinase and QRS scores were used to estimate total infarct size and left ventricular infarct size respectively. The anterior infarcts were of similar size to the inferior infarcts as determined by peak creatine kinase (1444 [mean] +/- 1161 [SD] U/L versus 1484 [mean] +/- 1182 [SD] U/L, respectively, P = 0.91) and peak aspartate transaminases (174 +/- 112 U/L versus 164 +/- 102 U/L, P = 0.78). The anterior myocardial infarct group had a greater percentage of the left ventricle infarcted on QRS scoring than the inferior infarct group (25.9 +/- 14.4% versus 11.1 +/- 6.0% respectively, P = 0.0004), lower global left ventricular ejection fraction (45.8 +/- 16% versus 54.6 +/- 9.2%, P = 0.04) and greater left ventricular regional wall abnormality. A significant negative correlation existed between left ventricular ejection fraction and peak creatine kinase for both groups, but was more marked with anterior infarction (r = -0.78, P less than 0.01) compared with inferior infarction (r = -0.49, P less than 0.05). Exercise-induced ST segment elevation was more frequent in the anterior than the inferior infarct group (59% versus 18%, P less than 0.02). However, both infarct locations had similar exercise tolerance, exercise-induced angina and ST segment depression. Despite equivalence of infarct size of the two infarct locations on enzyme testing, anterior infarction was associated with greater abnormality of left ventricular function with lower resting global left ventricular ejection fraction; greater resting left ventricular regional wall abnormality and greater exercise-induced ST segment elevation. These differences probably contribute to the poorer prognosis of patients with anterior infarction compared to those with inferior infarction of equivalent enzymatic size, given the previously well-documented prognostic importance of left ventricular function.     

Outcomes according to presentation with versus without cardiogenic shock in patients with left main coronary artery stenosis and acute myocardial infarction

This study is aimed at evaluating 1-year clinical outcomes and their predictors in patients with unprotected left main coronary artery (ULMCA)-related acute myocardial infarction (AMI). In total 248 patients diagnosed with AMI involving the ULMCA as the culprit vessel and registered in the Korean Acute Myocardial Infarction database were enrolled in this study. Patients were divided according to the absence (shock-, n = 206) or presence (shock+, n = 42) of cardiogenic shock at initial presentation. Independent risk factors of in-hospital cardiac death associated with ULMCA-related AMI were elucidated by multivariate regression analysis. In-hospital mortality rates were 8.7% in the shock- group and 47.6% in the shock+ group (p = 0.001). During 1-year follow-up after discharge, major adverse cardiac events developed in 16.3% of patients in the shock- group and 18.2% of patients in the shock+ group (p = 0.828); cardiac death, MI, and ischemia-driven target vessel revascularization were similar between the 2 groups at 1 year. On multivariate analysis, initial shock presentation (odds ratio 8.9, confidence interval 4.1 to 19.2, p = 0.004) and left ventricular ejection fraction <30% (odds ratio 7.6, confidence interval 2.7 to 21.1, p = 0.001) were independent risk factors of in-hospital cardiac death associated with ULMCA-related AMI. In conclusion, almost 1/2 of patients with ULMCA-related AMI presenting with cardiogenic shock had a fatal in-hospital outcome compared to <10% of those without cardiogenic shock; however, clinical outcomes after survival of the in-hospital period were not different between these groups.     

Cystatin C as prognostic biomarker in ST-segment elevation acute myocardial infarction

Cystatin C is a marker of renal dysfunction, and preliminary studies have suggested it might have a role as a prognostic marker in patients with coronary artery disease. The aim of the present study was to evaluate the usefulness of cystatin C for risk stratification of patients with ST-segment elevation myocardial infarction, regarding in-hospital and long-term outcomes. We included 153 consecutive patients with ST-segment elevation myocardial infarction treated by primary angioplasty. The baseline cystatin C level was measured at coronary angiography. The in-hospital outcome was determined as progression to cardiogenic shock or in-hospital death, and the long-term outcome was assessed, considering the following end points: (1) death and (2) death or reinfarction. Of the 153 patients evaluated (age 61 ± 12 years; 75.6% men), 15 (14.4%) progressed to cardiogenic shock and 4 (2.7%) died during hospitalization. The patients who progressed to cardiogenic shock or died during hospitalization had significantly greater cystatin C levels (1.02 ± 0.44 vs 0.69 ± 0.24 mg/L; p = 0.001). Long-term follow-up was available for 130 patients (583 ± 163 days). Among them, 11 patients died and 7 had reinfarction. A high baseline cystatin C level was associated with an increased risk of death (hazard ratio 8.5; p = 0.009) and death or reinfarction (hazard ratio 3.89; p = 0.021). Furthermore, only high baseline cystatin C levels and left ventricular ejection fraction ≤40% were independent predictors of the long-term risk of death, with synergistic interaction between the 2. In conclusion, cystatin C is a new biomarker with significant added prognostic value for patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention, predicting both short- and long-term outcomes.     

Factors that predict improvement in left ventricular ejection fraction after coronary angioplasty for acute myocardial infarction

Acute and follow-up angiograms were analyzed in 75 patients with acute myocardial infarction treated with emergency coronary angioplasty to determine factors that might predict improvement in left ventricular ejection fraction. Ejection fraction improved 8.4 +/- 8.2% in 60 patients who maintained patent infarct vessels at follow-up angiography, compared with -4.1 +/- 6.0% in 15 patients who developed reocclusion (p less than .001). In patients with patent infarct vessels, univariate analysis revealed the following significant predictors of improvement in ejection fraction: initial ejection fraction (r = -.38, p less than .003) subtotal vs total stenosis (12.9 +/- 9.3% vs 6.9 +/- 7.3%, p less than .02), infarct vessel (left anterior descending 11.0 +/- 8.4%, right 6.8 +/- 6.4%, circumflex 2.6 +/- 7.5%, p less than .02), and time to follow-up study (less than or equal to 15 days vs greater than 15 days) (4.8 +/- 5.8% vs 9.8 +/- 8.6%, p less than .03). Reperfusion time (less than or equal to 2 hr vs greater than 2 hr) predicted improvement when subtotal stenoses and stuttering infarctions were excluded (10.6 +/- 7.0% vs 4.9 +/- 6.9, p less than .03). Multivariate analysis showed initial ejection fraction and subtotal vs total stenosis to be independent predictors. Patients with anterior infarctions, low initial ejection fractions, and subtotal stenoses or reperfusion times less than or equal to 2 hr are likely to benefit most from coronary angioplasty for acute myocardial infarction.