Interventional procedures in acute myocardial infarction.

Acute myocardial infarction (AMI) is a leading cause of death in the western world. Primary percutaneous intervention (PCI) has emerged as an effective therapy that may improve survival and decrease morbidity in patients with AMI. Our article discusses the advantages of PCI over thrombolytic therapy and reviews currently available techniques. Rescue angioplasty, adjunctive pharmacologic therapies, economic and feasibility considerations are also discussed. Emerging therapies are also addressed. Evidence supports the first-line use of PCI for AMI. Furthermore, primary PCI appears superior to thrombolytic therapy for AMI in many patient populations, especially the elderly, patients with prior coronary artery bypass surgery, patients with congestive heart failure and in patients with cardiogenic shock. Advancements in equipment and techniques and emerging adjunctive therapies will continue to enhance this therapy and improve its efficacy.

Predictive value of the Killip classification in patients undergoing primary percutaneous coronary intervention for acute myocardial infarction.

The predictive value of Killip classification of acute myocardial infarction (AMI) in patients undergoing percutaneous coronary intervention (PCI) is not well established. We performed a pooled analysis of 2,654 patients with AMI enrolled in 3 primary angioplasty trials. Of these, 2,305 patients were class I, 302 were class II, and 47 were class III (class IV patients were excluded). Univariate and multivariate analyses were performed to determine if Killip class at admission was a predictor of in-hospital and 6-month mortality. Higher Killip classification was associated with greater in-hospital (2.4%, 7%, and 19% for class I, II, and III, respectively) and 6-month mortality (4%, 10%, and 28% for class I, II, and III, respectively). Higher Killip class was associated with increased age (p <0.001), history of diabetes (p <0.02), lower systolic blood pressure and higher heart rate at presentation (p <0.0001 for both), more 3-vessel disease (p <0.001), lower left ventricular ejection fraction (p <0.0001), and higher peak creatine phosphokinase (p <0.0001). With each increasing Killip class, there was an increased need for an intra-aortic balloon counterpulsation (p <0.001) and greater incidence of renal failure (p <0.001), major arrhythmia (p <0.001), and major bleeding (p <0.001). After controlling for potential confounding variables, Killip classification remained a multivariate predictor of mortality at both time end points. Killip classification at hospital admission remains a simple and useful independent predictor of in-hospital and 6-month mortality in patients with AMI who are undergoing primary PCI.

Interventional procedures in acute myocardial infarction.

BACKGROUND: Acute myocardial infarction (MI) remains a leading cause of death in the United States. There is evidence that primary (direct) percutaneous intervention (PCI) may improve survival and reduce morbidity in patients with acute MI. METHODS: We present a concise, comprehensive, evidence-based literature review of modern techniques of primary PCI in patients with acute MI. A comparison to thrombolytic therapy, especially in selected patient subgroups is made. Rescue angioplasty is also addressed. Adjunctive pharmacology, economic implications, and feasibility of implementation are discussed. A brief discussion of experimental therapies is included. RESULTS: Primary PCI is an acceptable alternative to thrombolytic therapy in patients with acute MI and may result in superior outcomes in select patient populations, especially the elderly, patients with prior coronary artery bypass surgery, those with congestive heart failure, and those in cardiogenic shock. CONCLUSIONS: Clinical trials support the use of primary PCI as first-line therapy for acute myocardial infarction. Patients in whom thrombolytic therapy is contraindicated or known to have reduced efficacy are also excellent candidates for this therapy. Ongoing advancements in equipment and adjunctive therapies continue to enhance delivery of this treatment as well as improve patient outcome.

Angiographic and clinical characteristics associated with increased in-hospital mortality in elderly patients with acute myocardial infarction undergoing percutaneous intervention (a pooled analysis of the primary angioplasty in myocardial infarction trials).

Advanced age is associated with increased mortality in acute myocardial infarction (AMI) but the mechanism remains unclear. We performed a pooled analysis of 3,032 patients from the Primary Angioplasty in Myocardial Infarction (PAMI)-2, Stent-PAMI, and PAMI-No Surgery On Site trials to determine which clinical, hemodynamic, and angiographic characteristics in the elderly were associated with in-hospital death. There were 452 patients aged >/=75 years and 2,580 patients aged <75 years. Older patients had a lower number of risk factors for coronary artery disease but more comorbidities. Acute catheterization demonstrated more 3-vessel disease, higher left ventricular (LV) end-diastolic pressure, lower LV ejection fraction, and higher initial rates of Thrombolysis In Myocardial Infarction (TIMI) trial 2 or 3 flow. Elderly patients were equally likely to undergo percutaneous intervention but had a lower procedural success rate and lower rates of final TIMI 3 flow, and older patients were more likely to have post-AMI complications. In-hospital mortality was 10.2% and 1.8%, respectively (p = 0.001). Cardiac and noncardiac mortality was higher in elderly patients, and no significant differences in causes of death were identified. Multivariate analysis revealed that the strongest predictors of death were age >/=75 years, lower LV ejection fraction, lower final TIMI flow, higher Killip class, need for an intra-aortic balloon pump (IABP), and post-AMI stroke/transient ischemic attack, or significant arrhythmia. Despite avoiding thrombolysis, elderly patients remain at increased risk of bleeding, stroke, and other post-AMI complications, and death. Cardiac risk factor analysis and acute catheterization offer prognostic information but do not completely explain the mechanism of increased in-hospital mortality in the elderly.

Variation of flow propagation velocity with age.

Flow propagation velocity is a new color Doppler M-mode measurement of left ventricular filling characteristics. This study was designed to establish normal values for this measurement in healthy individuals and to compare these findings with pulsed Doppler transmitral velocities. Complete M-mode, two-dimensional, and Doppler echocardiographic studies were performed on 64 volunteers between 21 and 79 years of age. Significant negative correlations (p < 0.001) with age were noted for flow propagation velocity (r = -0.59), peak early diastolic filling velocity (r = -0.65), and peak early diastolic filling/peak atrial filling ratio (r = -0.80). Positive correlations (p < 0.001) with age were observed for peak atrial filling velocity (r = 0.50) and atrial filling velocity integral (r = 0.71). Flow propagation velocity decreased by 44% between the youngest and oldest age groups. We conclude that flow propagation velocity is influenced by age and that it compares favorably with transmitral Doppler indices of left ventricular filling in this regard. These age-related alterations are present in healthy individuals, in the absence of any apparent cardiovascular disease.