Incidence of immunoglobulin G antibodies to Chlamydia pneumoniae in acute myocardial infarction patients.

BACKGROUND: Recent studies have suggested a possible association between Chlamydia pneumoniae infection and coronary heart disease. OBJECTIVES: To determine titers of antibodies to C. pneumoniae in patients with acute myocardial infarction compared with titers in several control groups. METHODS: This prospective case-control study investigated 209 individuals. We assessed the serum IgG antibody titers to C. pneumoniae in 57 consecutive patients admitted with AMI to our intensive coronary care unit during a 4 month period. A serum sample was drawn upon admission and after 6 weeks. Results were compared with those of four control groups: a) patients admitted with community-acquired pneumonia (n = 18), b) patients with community-acquired urinary tract infection (n = 42), c) patients with angiographically normal coronary artery disease (n = 44), and d) patients with stable coronary artery disease (n = 48). Serum immunoglobulin G antibody titers to C. pneumoniae were determined using standard micro-immunofluorescence technology. RESULTS: Of 57 patients with AMI, 32 (56%) had a high IgG titer to C. pneumoniae (> or = 1:256) on the initial test, which remained unchanged (62%) after 6 weeks. The percentage of patients with high titers was significantly lower in the control groups: 5 of 18 patients (28%) in the pneumonia group (P < 0.01), 11 of 42 (26%) in the urinary tract infection group (P < 0.01), 11 of 44 (25%) with normal coronary arteries (P < 0.01), and 17 of 48 (35%) with stable chronic ischemic heart disease (P < 0.05). CONCLUSION: The detection of high titers of IgG antibodies to C. pneumonia in many patients with AMI, compared to control groups, suggests that chronic Chlamydia pneumoniae infection plays a role in the pathogenesis of atherosclerosis and acute ischemic events.

Treatment and outcome of patients with acute myocardial infarction and prior cerebrovascular events in the thrombolytic era: the Israeli Thrombolytic National Survey.

BACKGROUND: Patients with a history of stroke presenting with acute myocardial infarction (MI) are often excluded from thrombolytic therapy owing to fear of intracranial hemorrhage. Few data, however, are available on the risks vs the benefits of thrombolysis in patients with an acute MI and a prior cerebrovascular event (PCE). METHODS: Data were derived from 2 nationwide surveys of 2012 consecutive patients with acute MI admitted to all 25 coronary care units in Israel during 1992 and 1994. Thrombolytic therapy was given to patients with a PCE at the discretion of the treating physicians. Outcomes were compared between patients with an acute MI with and without a PCE and between patients with a PCE treated with or excluded from thrombolysis. RESULTS: Patients with a PCE (n = 115 [6%]) were older, with higher rates of atherosclerotic risk factors and in-hospital complications than their counterparts without a prior event (n = 1897). They were treated less often with thrombolysis or mechanical reperfusion. The 1-year mortality rates were higher among patients with a PCE (28% vs 19%, P<.01), but not after multivariate adjustments for clinical characteristics (adjusted hazard ratio, 1.08; 95% confidence interval, 0.75-1.55). Patients with an acute MI and a PCE who were treated with thrombolysis (n = 29 [25%]) were compared with 46 patients found ineligible for thrombolysis primarily because of their PCE. The timing of the PCE was comparable in both groups (one fifth in the preceding year), while prior transient ischemic attacks were more prevalent among patients who had undergone thrombolysis. The patients who were treated with thrombolysis (n = 29) were older, had a higher rate of anterior infarction, and, while in the hospital, received aspirin, anticoagulants, and beta-blockers more often than their counterparts (n= 46). In-hospital intracranial hemorrhage did not occur in either group. The 1-year mortality rates were 2-fold higher among patients who had not undergone thrombolysis compared with those who had (33% vs 18%; adjusted hazard ratio, 2.44; 95% confidence interval, 0.78-7.64). CONCLUSIONS: These findings, derived from 2 nationwide surveys of consecutive patients with acute MI, suggest that patients with PCEs have an adverse outcome attributed to their older age and less favorable risk profile. Thrombolytic therapy, however, based on our preliminary data, may be beneficial in selected patients with an acute MI with a nonrecent PCE.

Smoking and prognosis after acute myocardial infarction in the thrombolytic era (Israeli Thrombolytic National Survey).

OBJECTIVES: This study sought to compare the relation between smoking and the 30-day and 6-month outcome after acute myocardial infarction in an Israeli nationwide survey. BACKGROUND: Studies before and during the thrombolytic era reported similar or lower early mortality after acute myocardial infarction in smokers than in nonsmokers. This finding is intriguing and may be misleading because numerous epidemiologic studies have clearly shown that smoking is an independent risk factor for atherosclerosis, myocardial infarction and death. METHODS: The study cohort comprised 999 consecutive patients with an acute myocardial infarction from a prospective nationwide survey conducted during January and February 1994 in all coronary care units operating in Israel. The prognosis of 367 patients (37%) who were smokers (current smokers and those who smoked up to 1 month before admission) was compared with that of 632 nonsmokers (past smokers or those who never smoked). RESULTS: Smokers were on average 10 years younger and were more frequently men and patients with a family history of coronary heart disease and inferior infarction and less frequently patients with a previous infarction or a history of angina, hypertension and diabetes than nonsmokers. Smokers also had a lower incidence of congestive heart failure on admission or during the hospital period. Thrombolytic therapy (49% vs. 40%, p < 0.01) and aspirin (89% vs. 80%, p < 0.001) were administered more frequently in smokers than nonsmokers. The crude 30-day (6.0% vs. 15.7%) and cumulative 6-month (7.9% vs. 21.5%) mortality rates were significantly lower (p < 0.0001 for both) in smokers than nonsmokers, respectively. However, after adjustment for age, baseline characteristics, thrombolytic therapy and invasive coronary procedures, the lower 30-day (odds ratio [OR] 0.75, 95% confidence interval [CI] 0.43 to 1.29, p = 0.30) and 6-month (hazard ratio 0.84, 95% CI 0.54 to 1.30, p = 0.42) mortality rates in smokers and nonsmokers were not significantly different. The model had a power of 0.80 for OR 0.50, with alpha 0.1. CONCLUSIONS: In our nationwide survey, the seemingly better prognosis of smokers early after acute myocardial infarction was no longer evident after adjustment for baseline and clinical variables and may be explained by their younger age and a more favorable risk profile. Smokers develop acute myocardial infarction a decade earlier than nonsmokers. Efforts to lower the prevalence of smoking should continue.

Asymptomatic hyperglycemia in coronary heart disease: frequency and associated lipid and lipoprotein levels in the bezafibrate infarction prevention (BIP) register. The BIP Study Group.

BACKGROUND: The lipid profile of patients with type-II diabetes is characterized by low levels of high-density lipoprotein cholesterol, hypertriglyceridemia, and increased levels of lipoprotein (a), all of which may affect the prognosis in patients with atherosclerotic cardiovascular disease. This study aimed to assess the prevalence of asymptomatic hyperglycemia and the associated lipid profile in a large group of patients with documented coronary heart disease. METHODS: From February 1990 to October 1992, 14,326 patients aged 45-74 years with documented coronary heart disease (a history of myocardial infarction or angina pectoris) were screened for inclusion in a secondary prevention study using bezafibrate retard. All screened patients underwent a medical examination and a blood test after fasting for 14 h. Asymptomatic hyperglycemia was defined as a fasting blood glucose level of 140 mg/dl or above in patients with no previous history of diabetes mellitus. RESULTS: The prevalence of asymptomatic hyperglycemia was 4%, with no differences between the sexes or age groups. Total cholesterol and triglyceride levels were significantly higher and the high-density lipoprotein cholesterol level significantly lower in asymptomatic hyperglycemic than in normoglycemic patients. After multiple adjustments, the relative risk of death was 1.75 and 1.71 in patients with diabetes or asymptomatic hyperglycemia compared with those with no glycemic disorders. CONCLUSION: Asymptomatic hyperglycemia was detected in 4% of patients with ischemic heart disease. The lipid profile in these 4% resembles that of patients with confirmed diabetes, and their morbidity and mortality may therefore be higher than that of normoglycemic patients. Repeated assessment of glucose levels in patients with coronary heart disease is mandatory.

A prospective randomized trial of intravenous magnesium versus intravenous propranolol in acute myocardial infarction.

A total of 266 patients entered into a study comparing the effect of intravenous magnesium and propranolol following acute myocardial infarction. Of these, 97 were able to receive either drug and were therefore randomized into the magnesium (n = 51) or propranolol group (n = 46). 88 patients were unable to receive propranolol and formed a third group (NR) while a further 81 patients could not receive either drug and formed a fourth group (N). The study showed that intravenous magnesium was as effective in preventing potentially lethal arrhythmias as propranolol and could be given to some 70 per cent of such patients whereas propranolol could only be given to 36 per cent.

Long-term follow-up after acute myocardial infarction in patients randomized to treatment with intravenous magnesium or intravenous propranolol in the acute phase.

Ninety-five patients with acute myocardial infarction were followed up for 6 months to 3 years (mean 25.4 months) in a preliminary study to compare the effects of intravenous magnesium (49 patients) with that of intravenous propranolol (44 patients) given immediately after admission to the intensive care unit. There were four cardiac deaths in the propranolol group and no deaths in the magnesium group (P < 0.046) and 27 per cent of patients who received propranolol subsequently developed cardiac failure as opposed to 12 per cent of those who had received magnesium (P < 0.04). Intravenous magnesium given in the early stages of myocardial infarction reduces the subsequent cardiac death rate possibly by reducing infarct size.

Progression and regression of coronary artery disease in one year. Quantitative angiographic assessment in patients with stable angina pectoris.

The rate of progression of coronary artery stenoses (CAS) is not clear. Spontaneous regression may also occur. Seventy-one CAS in 25 patients who were enrolled in a study of the effects of chromium on CAS were analysed. Coronary angiography was performed in multiple views and patients randomised to chromium or placebo treatment. Videodensitometric quantitative analysis was performed using a Vanguard XR70 Analyzer. After 1 year all patients were recatheterised. Corresponding frames from identical views were analysed. CAS were assessed with the observers blinded to the initial study results. No differences were found between chromium or placebo and the results have been combined. There was no overall progression of CAS as assessed by % area stenosis (p = 0.65), % diameter stenosis (p = 0.19), stenotic area (p = 0.87), or stenotic diameter (p = 0.99). However, 20% of individual lesions progressed, while 10% regressed, and 70% remained the same. These changes must be taken into account in studies of interventions which may modify the course of coronary atherosclerosis, and if coronary by-pass surgery is to be performed with a 1 year delay after angiography.

Reproducibility of measurements of coronary narrowings by videodensitometry and by digital calipers.

Computer-assisted videodensitometry has been shown to be a reliable and reproducible method of measuring absolute and relative coronary narrowings. Using a commercially available analyzer (Vanguard XR70) we confirmed intra- and interobserver reproducibilities in 34 narrowings in 9 patients. Analyses were performed on normal area and diameter, stenotic area and diameter, percent area stenosis and percent diameter stenosis. For all 6 analyses, excellent intra- and interobserver correlations were found (r = 0.93-0.98), with slopes close to 1 and intercepts close to zero. Caliper measurements (Mitutoyo Digimatic) of the same lesions by the same observers showed good inter- and intraobserver reproducibility for percent diameter stenosis (r = 0.90 and 0.86), with mean interobserver difference of 1.67 +/- (SD) 6.4% and intraobserver difference of 2.97 +/- (SD) 7.9%. However, less good correlations were found between caliper and videodensitometric measurements of percent diameter stenosis; r = 0.61 and 0.76 for the two observers. These data suggest that videodensitometry is a highly reproducible quantitative angiographic method, suitable for documenting changes in the severity of coronary artery lesions, both spontaneous or related to interventions. Caliper measurements do not provide the same degree of accuracy, but they have acceptable reproducibility in measuring diameter stenosis. As such, they are also suitable for assessing changes in severity of coronary artery lesions in individual patients.

Use of pulmonary artery catheters in patients with acute myocardial infarction. Analysis of experience in 5,841 patients in the SPRINT Registry. SPRINT Study Group.

This study analyzes the use of PAC in a registry comprising 5,841 hospitalized patients with AMI. A total of 371 patients received PAC. In-hospital mortality was higher in patients with CHF who received PAC, while there was no difference in patients with cardiogenic shock or persistent hypotension. Mortality in patients receiving PAC was higher irrespective of the presence or absence of "pump failure." A separate analysis of discharge summaries of 364 patients with CHF showed that PAC was used more frequently in sicker patients and that when severity of CHF was assessed, no difference in mortality was found in patients with mild or moderate CHF. We conclude that while a higher in-hospital mortality is found in patients receiving PAC, this excess is likely related to difference in severity of CHF, which had not been assessed in every individual. It is unlikely that PAC increases mortality.

Platelet adenylate cyclase and phospholipase C activity in posttraumatic stress disorder.

Adenylate cyclase and phospholipase C activity were examined in platelet membranes obtained from 19 male subjects with combat-related posttraumatic stress disorder (PTSD) and 35 age- and gender-matched healthy controls. Basal and forskolin-stimulated adenylate cyclase activity were significantly lower in the PTSD group whereas aluminum chloride plus sodium fluoride (AlCl3/NaF)- and prostaglandin E1 (PGE1)-stimulated responses were normal. There was no difference in phospholipase C activity between the two groups. The lower basal and forskolin-stimulated adenylate cyclase responses replicate a previous report and suggest that PTSD may be associated with an abnormality of the catalytic subunit of the receptor-adenylate cyclase complex.

Continuous intravenous infusion of magnesium sulfate after acute myocardial infarction.

Two hundred and fifty patients admitted with acute myocardial infarction were treated with a continuous infusion of magnesium sulfate for 24 h (a total of 46 mmol of elemental magnesium). Only 1 patient had ventricular fibrillation; no patient had sustained ventricular tachycardia requiring cardioversion. Twenty-five patients had short runs of non-sustained ventricular tachycardia and did not need cardioversion. In 6 further patients, the infusion had to be discontinued because of a drop in blood pressure. The in-hospital mortality for the group was 3.4%.

Reproducibility of measurements of coronary narrowings by videodensitometry: unreliability of single view measurements.

Computer-assisted videodensitometry has been shown to be a reliable and reproducible method of measuring absolute and relative coronary narrowings. Using a commercially available analyzer (Vanguard XR70) we confirmed the intra- and interobserver reproducibilities in 34 narrowings in 9 patients. Analyses were performed on normal area and diameter, stenotic area and diameter, percent area stenosis and percent diameter stenosis. For all 6 analyses, excellent intra- and interobserver correlations were found (r = 0.93-0.98), with slopes close to 1 and intercepts close to zero. In a separate study of 16 lesions in 11 patients, each lesion was analyzed in both the RAO and LAO planes. Correlation between the measurements was reasonable with r = 0.76 for the stenotic area and r = 0.75 for the absolute diameter stenosis. However, with suboptimal slopes (0.54 and 0.63 respectively), actual differences between measurements in the two planes were often unacceptably large. These data suggest that videodensitometry is a highly reproducible quantitative angiographic method; however, single view analyses are inadequate for comparative studies.

Acquired obstruction of the ventricular septal defect in tetralogy of Fallot.

The interventricular septal defect in patients with tetralogy of Fallot is, in most cases, a nonrestrictive malalignment type of defect. Rare examples of a restrictive defect have been described. We report a case of tetralogy of Fallot with pulmonic atresia in which the interventricular septal defect was found to be nonrestrictive at birth. The obstruction of the defect developed gradually, until, at the age of 6 years, a gradient of 55 mm Hg across the defect was found at repeat cardiac catheterization. Echocardiography proved that the acquired obstruction was due to excessive tricuspid valve tissue, while Doppler studies suggested a similar gradient between the right ventricle and the ascending aorta. This rare case should alert the clinician to the possibility of an acquired obstruction of the ventricular septal defect, with suprasystemic right ventricular pressure, in cases of tetralogy of Fallot, even if an early study suggested a nonobstructive defect. The diagnosis of this situation is of importance because of the poor prognosis which it carries.

Effects of enalapril on lymphocyte sodium, potassium, magnesium and calcium levels in patients with severe congestive heart failure.

Fifteen patients (median age 73 years) with severe congestive heart failure were treated with Enalapril for a total of 12 weeks with a significant improvement in their right atrial pressures and in their functional state. Renal function, serum potassium, magnesium and calcium levels were unchanged. Lymphocyte sodium, potassium and calcium levels were generally lower than control values throughout the study but these differences were only statistically significant early in the study. Lymphocyte magnesium levels were unchanged. These findings are in contrast to those previously reported in the literature for such patients treated with conventional diuretics.

Magnesium in the prevention of lethal arrhythmias in acute myocardial infarction.

Seven of 48 patients (14.6%) with acute myocardial infarction who were given 2.4 g of magnesium sulfate as a single intravenous dose had potentially lethal arrhythmias during the first 24 hours after admission, whereas 16 (34.8%) of 46 patients receiving placebo had similar arrhythmias. In addition, 14 of these 16 patients in the placebo group had their first arrhythmia (in the intensive coronary-care unit) within two hours after the start of the study, whereas in the magnesium-treated group, there were no such arrhythmias until some four hours later. The higher the lymphocyte potassium concentration, the greater the reduction in the incidence of arrhythmias. Serum magnesium levels increased by 16.5% and lymphocyte magnesium concentrations by 72% in the magnesium treated group. Intravenous magnesium reduces the incidence of serious arrhythmias after acute myocardial infarction.

Intracellular cations and diuretic therapy following acute myocardial infarction.

In a controlled, prospective, randomized study of the effects of diuretic therapy on serum, lymphocyte, and erythrocyte potassium, magnesium, and calcium concentrations, 155 patients were followed up for six months after experiencing acute myocardial infarction. Of these, 48 patients received furosemide and potassium; 37 patients received hydrochlorothiazide and amiloride hydrochloride; and 70 patients did not require diuretics. Lymphocyte and erythrocyte cation concentrations were all statistically significantly lower in the furosemide-treated patients when compared with the patients in the nondiuretic-therapy group or the hydrochlorothiazide-amiloride-treated group, with no change in serum levels. Since the combination of low intracellular potassium and magnesium concentrations in patients with recent myocardial infarction may be of importance in the cause of arrhythmias, we suggest that potassium- (and magnesium-) sparing diuretics be used in the treatment of patients, when necessary, unless their diuretic needs cannot be met by such agents.

Anomalous origin of the left coronary artery from the pulmonary artery: new electrocardiographic, echocardiographic and surgical observations.

The case of a two year old girl with anomalous origin of the left coronary artery from the pulmonary artery is described. She was never in heart failure but had cardiomegaly and anginal pain. The ECG showed a typical infarct pattern with left ventricular hypertrophy. An unusual finding was a prolonged QTc of 0.52. During cardiac catheterization and twice 24 hours later she developed ventricular fibrillation treated with electroshock and prevented later with propranolol. The QTc returned to normal after surgery. Echocardiography showed diastolic flutter and early systolic closure of the pulmonary valve. This disappeared after surgical correction. Transverse 2D echo of the aortic root showed a large right coronary artery which decreased in size after surgery. The left coronary artery was not seen on echocardiography. At cardiac catheterization the diagnosis of an anomalous origin of the left coronary artery from the pulmonary artery was established, with a large shunt to the pulmonary artery through the anomalous artery. Mild pulmonary hypertension and mild mitral regurgitation were present. At surgery, since direct implantation was technically impossible, the left coronary artery was successfully connected to the aorta via a 6 mm expanded Poly-Tetra-Fluoro-Ethylene (P.T.F.E.) graft.