Late reperfusion (6-24 hours after onset) improves left ventricular function in patients with acute myocardial infarction.

The TAMI-6 trial has demonstrated that coronary reperfusion >6h after onset (ie, late reperfusion) in patients with acute myocardial infarction (AMI) does not improve left ventricular (LV) function during the chronic phase of infarction. However, the low patency rate (only 60%) of the infarct-related artery (IRA) during the chronic phase in the TAMI-6 trial raises a new hypothesis that late reperfusion with a higher patency rate may improve LV function during the chronic phase. Forty-four patients with AMI, who were admitted to hospital 6-24h after the symptom onset and in whom emergency coronary angiography revealed a total occlusion of the IRA, were randomly assigned to either the late reperfusion group (n=22) or the non-reperfusion group (n=22). The initial success rate of reperfusion therapy in the late reperfusion group was 86% and the chronic patency rate of the IRA was 91%. The improvements in ejection fraction and chord shortening in the infarct region from the acute phase to the chronic phase were significantly greater in the late reperfusion group than in the non-reperfusion group. Late reperfusion with a high patency rate of the IRA significantly improves LV global and regional function in patients with AMI.

Is inflammation related to the clinical severity of unstable angina?

The present study determined the white blood cell (WBC) count and the serum C-reactive protein (CRP) level in 27 patients with coronary spastic angina, 16 with Braunwald class IB unstable angina (UA) and 13 with Braunwald class IIIB. The relationship between the clinical presentation of UA and the requirement for emergency percutaneous transluminal coronary angioplasty (PTCA) was examined, and in patients with medically refractory angina, the determining factor among the clinical manifestations of angina was also investigated. In the acute phase, the WBC count and the serum CRP level were significantly higher in patients with Braunwald class IIIB than in those with coronary spastic angina or Braunwald class IB UA (p<0.001). In the Braunwald class IIIB group, a significantly higher rate of patients required emergency PTCA than that of the coronary spastic angina group (p<0.01). Patients with medically refractory angina had a significantly higher WBC count and higher serum CRP level on admission, and the WBC count on admission was independently associated with medically refractory angina by multivariate analysis (p<0.05). Inflammation may play a major pathological role in the rapid development of acute coronary syndrome.

Appropriate indications for the use of a percutaneous cardiopulmonary support system in cases with cardiogenic shock complicating acute myocardial infarction.

Percutaneous cardiopulmonary support (PCPS) is now available for hemodynamic support in patients with cardiogenic shock, but there are no guidelines for its use. The present study determined the appropriate indications for the use of the PCPS in patients with cardiogenic shock complicating acute myocardial infarction (AMI). Sixty-four consecutive patients with cardiogenic shock complicating AMI had hemodynamic support with an intraaortic balloon pump (IABP; n=38) and/or PCPS (n=26). The shock score (0-15) was calculated immediately before starting these support systems to quantify the severity of shock. Multivariate logistic regression analysis determined the clinical factors affecting in-hospital mortality. The relationship between in-hospital prognosis and the shock score was also examined in the 2 groups. The most significant factor related to the in-hospital prognosis was the shock score (p=0.0007; OR 2.16, 95% CI: 1.37-3.39). Another related factor was revascularization; however, this relationship did not reach statistical significance (p=0.069; OR 0.06). Among the 13 cases whose shock score was 4-8 (moderate shock), 5 survived in the PCPS group, but only 1 of 19 patients survived in the IABP group (p<0.05). None of the patients in either group whose shock score was more than 9 survived. The severity of shock is the most reliable independent predictor of in-hospital mortality in patients with cardiogenic shock complicating AMI. Using PCPS in patients with moderate cardiogenic shock may improve their in-hospital survival, but it must be used before the shock becomes severe.

Usefulness of serum troponin T levels on day three or four in predicting survival after acute myocardial infarction.

The appearance of serum troponin T (tn-T) on day 1 after acute myocardial infarction (AMI) strongly depends on coronary reperfusion. In contrast, the kinetics of tn-T release after day 1 after AMI are unaffected by the reperfusion status, and reflect the degradation of myofilaments in irreversibly damaged cells. However, it is not known whether serum tn-T levels after day 1 after AMI can be used to predict the long-term outcome. The purpose of this study was to elucidate the prognostic value of determining the tn-T level on day 3 or 4 after AMI. Serum tn-T levels on day 3 or 4 after AMI were measured in 121 patients (92 men and 29 women, mean age 65 years). Mean follow-up period was 526 days. There were 12 deaths (9 cardiac and 3 noncardiac) during the follow-up period. By Kaplan-Meier analysis, patients with tn-T levels higher than the median level (6.9 ng/ml) had a significantly higher mortality rate than those with submedian levels (p <0.01). By multivariate Cox proportional-hazards regression analysis, the serum tn-T level was an independent predictor of the long-term outcome after AMI (p <0.01). Futhermore, in patients with a first AMI, the serum tn-T level exhibited a significant negative linear correlation with left ventricular ejection fraction assessed 4 weeks after AMI (r = -0.48, p <0.001). Increased serum tn-T levels on day 3 or 4 after AMI are a powerful noninvasive predictor of poor long-term prognosis, reflecting residual left ventricular function after AMI.

Initial experience with nifekalant hydrochloride (MS-551), a novel class III antiarrhythmic agent, in patients with acute extensive infarction and severe ventricular dysfunction.

Nifekalant hydrocholoride, a novel class III antiarrhythmic agent, was used as the treatment in 4 patients with extensive anterior infarction and severe ventricular dysfunction. The malignant ventricular tachyarrhythmia was effectively suppressed at a relatively low dose, without compromising the hemodynamics, indicating that this potent K+ channel blocker has therapeutic potential for acute myocardial infarction.

Terminally alkylated heparin. 2. Potent antiproliferative agent for vascular smooth muscle cells.

The antiproliferative activity of alkylated heparin, in which the terminal end of heparin is derivatized with an alkyl group (butyl, octyl, lauryl, stearyl), was examined using vascular smooth muscle cells. The proliferation of cells, which were growth-arrested prior to addition of heparin, was inhibited in proportion to both increase in the chain length of the alkyl group of alkylated heparin and alkylated heparin concentration in the serum-containing medium. The antiproliferative activity of stearyl group derivatized heparin was significantly stronger than that of nonmodified heparin. Little proliferation was observed at high dose (500 microg/mL). Confocal laser scanning microscopic observation indicated that alkylated heparin was accumulated on the cell membranes at an early incubation time, followed by homogeneous distribution of intracellular space. The therapeutic potential of alkylated heparin for preventing restenosis after balloon angioplasty is discussed.

Dexamethasone-induced cardiogenic shock rescued by percutaneous cardiopulmonary support (PCPS) in a patient with pheochromocytoma.

A 52-year-old man with pheochromocytoma had cardiogenic shock and was rescued using a percutaneous cardio pulmonary supporting system. After recovery, diagnostic tests including metaiodobenzylguanidine scintigraphy and computed tomography, revealed the pheochromocytoma which was confirmed by histology. It was postulated that the acute episode was induced by intra-joint dexamethasone, which increased the production of epinephrine and augmented the sensitivity of cardiomyocytes for catecholamine, thereby inducing the cardiomyopathy.

Circulating hepatocyte growth factor as a marker of thrombus formation in unstable angina pectoris.

A new enzyme-linked immunosorbent assay can detect 10 pg/ml of human hepatocyte growth factor (HGF). Circulating HGF was significantly higher in patients with unstable angina (296+/-184 pg/ml, mean+/-SD, n=36) than in healthy volunteers (201+/-64 pg/ml, n=250, p<0.0001). Individual concentrations exceeded the mean control value +2 SD (329 pg/ml) in 12 of the 36 (33%) patients with unstable angina. The present study indicates that this new, sensitive HGF assay can successfully detect thrombosis in patients with unstable angina.

Esophageal perforation associated with profound shock successfully managed with hemodynamic assistance using percutaneous cardiopulmonary support.

A 51-year-old man was admitted to our hospital with complaints of severe chest pain, nausea, and vomiting. These symptoms had progressed rapidly and he was in shock. It was necessary to make a correct diagnosis as early as possible. However, the hemodynamic condition of the patient deteriorated rapidly before a definitive diagnosis could be established in spite of conventional therapies. Under hemodynamic assistance with percutaneous cardiopulmonary support (PCPS), a final diagnosis of esophageal perforation was made by esophagography. Our report illustrates a new application of PCPS for highly selected cases of noncardiogenic shock as a "bridge" until an accurate diagnosis is made and a specific treatment is applied.

Abnormal glucose tolerance, not small vessel diameter, is a determinant of long-term prognosis in patients treated with balloon coronary angioplasty.

AIMS: We sought to find out what factors are important for long-term prognosis, the small vessel itself or abnormal glucose tolerance, in patients treated with coronary angioplasty. BACKGROUND: Patients with coronary artery disease with diabetes mellitus often show diffuse and small coronary artery narrowing. Impaired glucose tolerance has also been reported to be a risk factor for cardiovascular disease. METHODS: Among 584 patients who underwent first elective balloon coronary angioplasty, diabetes mellitus and impaired glucose tolerance were present in 197 patients. Large and small vessels were defined by reference vessel diameter before coronary angioplasty as either larger or smaller than 2.5 mm. Patients were categorized into the following four groups: 175 patients with normal glucose tolerance and reference diameter <2.5 mm (group SN), 212 patients with normal glucose tolerance and reference diameter greater than or = 2.5 mm (group LN), 101 patients with abnormal glucose tolerance and reference diameter <2.5 mm (group SD), and 96 patients with abnormal glucose tolerance and reference diameter greater than or = 2.5 mm (Group LD). The cardiac events were compared for a period of 8 years after coronary angioplasty among the four groups. RESULTS: There was no difference in the percentage diameter stenosis immediately after coronary angioplasty among the four groups. However, group SD showed unfavourable prognosis despite similar minimal lumen diameter after coronary angioplasty compared with group SN. Event-free survival curve of group LD showed a sudden drop approximately 5 years after the coronary angioplasty. In multivariate analysis, the cardiac events were associated with the presence or absence of abnormal glucose tolerance. Furthermore, patients with bad glycaemic control (HbA1c>6.0%) at index coronary angioplasty showed worse event free survival than those with good glycaemic control. CONCLUSIONS: An important determinant for long-term prognosis after coronary angioplasty is a presence of abnormal glucose tolerance per se and not small vessel diameter.

[Risk factors and physical activity levels at the onset of acute myocardial infarction in young men].

OBJECTIVES: The pathogenesis and triggering factors of acute myocardial infarction in young men remain unknown. To clarify the pathogenesis of acute myocardial infarction in young Japanese men, we compared the clinical features of patients with acute myocardial infarction in 2 age groups in Japan. METHODS: There were 37 male patients aged < 40 years (Young group; mean age 36 +/- 4 years, range 23-39 years) among 2,879 patients with acute myocardial infarction admitted to the coronary care unit of the National Cardiovascular Center, Japan, from 1977 through 1996. The clinical features of this group were compared with those of 110 consecutive male patients with acute myocardial infarction aged > or = 65 years (Old group; mean age 72 +/- 6 years, range 65-96 years) admitted in 1993-1994. Demographic features, physical activity levels at or within 2 hours before the onset of acute myocardial infarction, and coronary angiographic findings were analyzed. RESULTS: Compared with the Old group, the Young group had lower incidences of hypertension (p < 0.01) and diabetes mellitus (p < 0.01), a higher incidence of smoking (p < 0.01), higher levels of total cholesterol (p < 0.05) and body mass index (p < 0.05), and a lower level of high-density lipopotein (HDL)-cholesterol (p < 0.01). Also, the Young group had a higher prevalence of 0-1 vessel disease than the Old group (72% vs 35%, p < 0.01). The physical activity level was significantly higher in the Young group than in the Old group (2.6 +/- 2.2 vs 1.8 +/- 1.1 METs, p < 0.01). Furthermore, patients with multivessel disease in the Young group had a higher incidence of hypertension, a higher level of total cholesterol and a lower level of HDL-cholesterol (all p < 0.05), whereas those with 0-1 vessel disease had a higher incidence of heavy smoking (73% vs 50%, p = 0.1) and a tendency to higher physical activity level at the onset (2.7 +/- 2.2 vs 2.4 +/- 2.3, NS). CONCLUSIONS: Young male patients with acute myocardial infarction may be characterized by 2 distinctive patterns: one associated with smoking and a higher physical activity level at the onset of acute myocardial infarction with 0-1 vessel disease and the other with hypertension and hypercholesterolemia with multivessel disease.

Enhanced secretion of cardiac hepatocyte growth factor from an infarct region is associated with less severe ventricular enlargement and improved cardiac function.

OBJECTIVES: We hypothesized that the hepatocyte growth factor (HGF) may play a cardioprotective role in human myocardial infarction (MI). BACKGROUND: The HGF is a novel, multifunctional growth factor implicated in wound healing, angiogenesis and promotion of cell survival. Recent animal studies have demonstrated the existence of an HGF system in the heart, where it is activated in response to myocardial ischemia and reperfusion. METHODS: We studied 40 patients with acute myocardial infarction (AMI), who underwent coronary reperfusion therapy upon admission. Approximately four weeks later, left ventricular (LV) catheterization was repeated to determine the LV ejection fraction (EF), end-diastolic volume index (EDVI) and pressure (EDP). The levels of HGF and brain natriuretic peptide (BNP) were measured by collecting blood samples from cardiac veins draining the infarcted region (MI region) and those draining the noninfarcted region (non-MI region). The ratio of the HGF level in the MI region to that in the non-MI region (= MI/non-MI ratio) was calculated in each patient as an index of the MI-related HGF secretion. The MI/non-MI ratio for BNP was also calculated. RESULTS: The MI/non-MI ratio for HGF correlated inversely with LVEDP (r = -0.644, p < 0.0001) and LVEDVI (r = -0.843, p < 0.0001) and positively with LVEF (r = 0.763, p < 0.0001). These correlations were completely opposite in direction from those for BNP and LVEDP (r = 0.678, p < 0.0001), LVEDVI (r = 0.783, p < 0.0001) and LVEF (r = -0.805, p < 0.0001). These findings indicate that cardiac HGF acts in contrast to BNP, a biochemical marker for the development of LV remodeling. CONCLUSIONS: Enhanced secretion of cardiac HGF from the MI region is associated with an attenuation of ventricular enlargement and an improvement in cardiac function. The HGF system may modulate the process of ventricular remodeling and thus have important clinical implications.