Acute myocardial infarction in young adults: prognostic role of angiotensin-converting enzyme, angiotensin II type I receptor, apolipoprotein E, endothelial constitutive nitric oxide synthase, and glycoprotein IIIa genetic polymorphisms at medium-term follow-up.

BACKGROUND: A number of reports have investigated the association between various gene polymorphisms and the phenotypic expression of myocardial infarction. No investigations have evaluated the prognostic role of genetic factors in young people with premature coronary disease. The aim of this study was to investigate the influence of genetic factors compared with that of conventional risk factors on follow-up events in a population of Italian young adults with myocardial infarction. METHODS AND RESULTS: The study population consisted of 106 young patients (mean age 40 +/- 4 years, range 23 to 45 years) with diagnosis of acute myocardial infarction. Clinical and genetic data from the group of patients with events during follow-up were compared with those from patients without events. The following genetic polymorphisms were tested: angiotensin I converting enzyme, angiotensin II type I receptor, apolipoprotein E (ApoE), endothelial constitutive nitric oxide synthase, and platelet glycoprotein IIIa. Coronary angiography was performed in 94 patients. Coronary angiography showed coronary artery disease in 93% of patients. During follow-up (46 +/- 12 months, range 25 to 72) the overall combined end points (cardiac death, myocardial infarction, and revascularization procedures) accounted for 21 events. Family history of coronary artery disease, smoking, stenosis of the left anterior descending artery at coronary angiography, and ApoE polymorphism (presence of epsilon4 allele) were significantly more prevalent (univariate analysis) in the group of patients with events. Logistic multivariate analysis showed that ApoE polymorphism (P =. 004, odds ratio [OR] 6.8, 95% confidence interval [CI] 2 to 22), family history (P =.005, OR 8.3, 95% CI 2 to 35), smoking after acute myocardial infarction (P =.008, OR 10.9, 95% CI 2 to 62), and left anterior descending coronary artery disease (P =.02. OR 6.6, 95% CI 1.3 to 33) were independent predictors of adverse events. CONCLUSIONS: Myocardial infarction at a young age is commonly characterized by evidence of multiple cardiovascular risk factors and by a favorable prognosis in short- and medium-term follow-up. Evidence of significant disease at coronary angiography suggests the presence of a premature atherosclerotic process. ApoE polymorphism (presence of epsilon4 allele) appears to be a strong independent predictor of adverse events, suggesting a remarkable influence in the accelerated coronary disease.

Subacute left ventricular free-wall rupture in early course of acute myocardial infarction. Clinical report of two cases and review of the literature.

Left ventricular free wall rupture (LVFWR) may complicate an acute myocardial infarction (AMI); its frequency ranges from 1 to 6 percent. In the era of coronary care units, LVFWR is the second cause of in-hospital death, after pump failure. The subacute presentation accounts for 2-3 percent of total hospital admissions for AMI. Heart rupture may not be suddenly fatal and sometimes there is enough time for surgical repair. Electromechanical dissociation is neither the only nor the main clinical presentation. More subtle symptoms occurring hours or days before the final event include unexplained hypotension and transient bradycardia and some ECG features such as persistent ST-segment elevation with T-waves failing to invert in the same leads. On echocardiographic subcostal view, pericardial effusion of more than 5-10 mm, with echo-dense masses overlying the heart independently of cardiac tamponade, is highly suggestive of heart rupture. If pericardiocentesis yields hemorrhagic fluid, surgical intervention is mandatory, providing both diagnostic confirmation and definitive treatment. Medical management strategies (prolonged bed rest, beta-blockade therapy) are still experimental but could become suitable for particular subsets of patients (elderly patients and patients at a high surgical risk). We report two cases of subacute LVFWR and review the currently available literature.

Lack of relationship between the P1A1/P1A2 polymorphism of platelet glycoprotein IIIa and premature myocardial infarction.

BACKGROUND: The P1A1/P1A2 polymorphism of the platelet glycoprotein IIIa has been variably associated with an increased risk of coronary thrombosis. MATERIALS: We investigated the linkage between the P1A1/P1A2 polymorphism and the risk of myocardial infarction in 98 patients who suffered their first myocardial infarction at the age of 45 years or less and 98 well-matched control subjects without coronary artery disease. Lipid parameters were measured using conventional methods of clinical chemistry; P1A genotypes were determined by polymerase chain reaction and restriction enzyme digestion. RESULTS: There was no significant difference in the prevalence of P1A2-positive genotypes (either P1A1/P1A2 or P1A2/P1A2) between patients and control subjects (chi 2 = 0.66, d.f. = 1, P = 0.41). CONCLUSIONS: These results suggest that the P1A2 polymorphism of the platelet glycoprotein IIIa does not contribute to the genetic susceptibility to premature myocardial infarction.

Fixed subaortic stenosis associated with hypertrophic cardiomyopathy: report of a rare familial occurrence.

INTRODUCTION: Fixed subaortic stenosis is considered to be an acquired condition. It is often associated with congenital heart disease, creating a turbulence in the left ventricle outflow tract. Familial forms of fixed subaortic stenosis are very unusual. We report a remarkable familial cluster in which fixed subaortic stenosis is associated with hypertrophic cardiomyopathy. METHODS: Fourteen relatives of a patient affected with hypertrophic cardiomyopathy and fixed subaortic stenosis underwent cardiological examination, electrocardiogram and echo-doppler study. RESULTS: Two of the proband's sisters showed an association between asymmetrical hypertrophic cardiomyopathy and fixed subaortic stenosis. The brother presented a subaortic ridge and concentric left ventricular hypertrophy. The other members of the family (another brother and the third-generation relatives) were unaffected. CONCLUSIONS: While the association between fixed subaortic stenosis and hypertrophic cardiomyopathy has commonly been reported, there is little in the literature to suggest the family-related nature of this association. The familial occurrence of this association reveals genetic transmission, with a recessive autosomal pattern of inheritance. This finding goes against the usual autosomal dominant pattern of inheritance in hypertrophic cardiomyopathy. Familial studies of FSS are needed in order to gain a better understanding of the genetic background of these patients.

Ischemic chest pain and global T-wave inversion in women with normal coronary angiograms.

Patients presenting with ischemic chest pain and electrocardiographic evidence of global T-wave inversion are most frequently women with intact left ventricular function and no critical stenosis of major coronary vessels. Hence, this syndrome has a good immediate and long-term prognosis.

New diagnostic criteria for infective endocarditis. A study of sensitivity and specificity.

OBJECTIVE: The purpose of this study was to determine the sensitivity and specificity of new criteria proposed by Duke University for case definition of infective endocarditis as compared to the previously accepted Von Reyn criteria. PATIENTS: A total of 143 consecutive suspected cases of infective endocarditis in 137 febrile patients were included. Of these, 69 had infective endocarditis, pathologically proven in 28, but with only a clinical diagnosis in 41. In the remaining 74 cases, the diagnosis of infective endocarditis was rejected after a follow-up of at least 3 months. RESULTS: The sensitivity of Duke's criteria was significantly higher, both when patients with possible infective endocarditis were considered as true-positive (definition 1; 100% vs 69%, P < 0.001) and when possible cases were considered as rejected (definition 2; 76% vs 51%, P < 0.01). Specificity was very high with both criteria: 92% Von Reyn vs 88% Duke (ns) with definition 1 and 99% Von Reyn vs 97% Duke (ns) with definition 2. The overall accuracy of the Duke criteria in the entire population was significantly higher with both definitions (0.94 vs 0.81 definition 1, P < 0.001; 0.87 vs 0.75, P = 0.015 definition 2). CONCLUSION: Duke's criteria for defining infective endocarditis has been shown to be more sensitive than previously adopted criteria, while maintaining a high degree of specificity. Therefore, they must be accepted as a substitute for previous criteria.

[Differences in pharmacologic treatment after acute myocardial infarction. The role of treatment effectiveness]. / Differenze nel trattamento farmacologico dopo infarto miocardico acuto. Ruolo dell'efficacia dei trattamenti.

BACKGROUND: Despite growing interest concerning the prescription of different drugs in different clinical settings, no explanatory variables have been determined. The aim of this study was to verify if there are any differences in drug prescription at the time of hospital release following myocardial infarction and if any of these differences can be explained by scientific evidence concerning treatment efficacy. METHODS: All drugs prescribed to 430 patients discharged from three different cardiology departments after acute myocardial infarction were analyzed. Based on current scientific evidence, it has been, ascertained that aspirin, beta-blockers and ACE-inhibitors can be prescribed unless contraindicate whereas anticoagulants, nitrates and calcium antagonists should be prescribed only in specific clinical conditions. The odd ratio of prescription of each drug among the three cardiology departments was calculated and adjusted for any clinical and test result variables that can specifically affect drug prescription. RESULTS: Different clinical characteristics of the patients discharged from the three cardiology departments are the following: mean age ranges from 60 to 66 years (p < 0.001), the incidence of non-Q myocardial infarction ranges from 23 to 45% (p < 0.001), post infarction angina ranges from 6 to 15% (p = 0.016), left ventricular failure ranges from 6 to 13% (p = 0.003) and arrhythmia ranges from 5 to 18% (p = 0.007). The adjusted odd ratio for clinical and test results variables showed that prescriptions were similar for ACE-inhibitors (odd ratio 1.3; 95% confidence interval from 0.6 to 3.2), aspirin (OR 2.2; 95% confidence interval from 0.8 to 5.5), beta-blockers (OR 2.2, 95% confidence interval from 0.9 to 5.5) and oral anticoagulants (1.6; 95% confidence interval from 0.6 to 4.5). Instead, there is a statistically significant difference in the prescription of nitrates (OR 4.4; 95% confidence interval from 1.6 to 12.3) and of calcium antagonists (OR 5.4%, 95% confidence interval from 1.0 to 12.5). CONCLUSIONS: Evidence based drug efficacy after acute myocardial infarction seems to establish a uniform pattern of drug prescription in different cardiology departments.

Diagnostic value of echocardiography in infective endocarditis: a probabilistic approach.

The high sensitivity and specificity of echocardiography in the diagnosis of infective endocarditis have been well established for a number of years. However, little is known yet about the incremental value of this technique over the clinical and serological findings already available in subsets of patients presenting different initial probabilities in infective endocarditis. In this report, sensitivity and specificity of echocardiography were calculated in 173 consecutive patients with suspected infective endocarditis who underwent echocardiography within 5 days following admission. The echocardiogram was considered positive when Duke major criteria were fulfilled. Infective endocarditis was diagnosed in 88 patients, while other illnesses in the remaining 85. The diagnoses were confirmed retrospectively with a follow-up done after at least 3 months, at surgery or during autopsy. Sensitivity and specificity of the echocardiography in this population were 85 and 97% respectively. The initial probabilities of infective endocarditis in patients with different clinical presentations were taken from a thorough review of the literature available in English and from personal research. The positive predictive value of echocardiography is already high or very high even at low or very low levels of initial probability, and this has a strong impact on clinical decisions. In these situations and with intermediate probabilities, a negative echocardiogram would theoretically rule out the disease. However, this result, if considered alone, calls for a careful reassessment of the entire clinical context. As with any other test, when the initial probabilities of infective endocarditis are highest, the incremental value of echocardiography is poor.

[Female sex is not an independent risk factor in mortality during myocardial revascularization]. / Il sesso femminile non rappresenta un fattore di rischio indipendente di mortalità negli interventi di rivascolarizzazione miocardica.

To assess if female sex is an independent risk factor for perioperatory mortality and morbidity, we have evaluated 971 consecutive patients (16% women) undergoing coronary artery bypass graft surgery at the Cardiovascular Disease Institution of the University of Turin from 1988 to 1990. In this study at baseline women were older and more likely to have diabetes, lower ventricular score and body surface area than men. As compared to men, women underwent surgery with delay: the surgical mortality rate and prevalence of arrhythmias were higher, and the size of the left anterior descending was smaller. At univariate analysis perioperative risk factors were as follows: age, diabetes, clinical instability, low body surface area, perioperatory infarction, postoperative infections, extracorporeal circulation time and left coronary size. At multivariate analysis only diabetes, left ventricular score, left anterior descending coronary size and emergency surgery were independent risk factors while sex, age and body surface area were not predictors of perioperatory mortality and morbidity. It is concluded that gender is not the cause of worse outcome in women.

Heart rate variability in the early hours of an acute myocardial infarction.

The occurrence of an autonomic disturbance early in acute myocardial infarction (AMI) has been reported: signs of sympathetic activation were mainly observed in relation to an anterior localization, whereas signs of vagal overactivity were more frequent in inferior wall AMI. Information is limited in relation to the persistence of these alterations during the early hours of AMI. We studied 33 patients with an AMI within 188 +/- 16 minutes from the onset of symptoms and 1 week after hospital admission. From a 20-minute Holter recording, we computed with autoregressive methodology, time and frequency domain indexes of heart rate variability. At admission, patients with an anterior wall AMI exhibited a smaller RR variance (593 +/- 121 ms2) than did those with an inferior wall AMI (1,122 +/- 191 ms2). In both groups the spectral profile was characterized by a predominant (73 +/- 4 and 61 +/- 4 normalized units) low frequency and by a small (13 +/- 2 and 22 +/- 3 normalized units) high-frequency component, indicating the presence of a sympathetic excitation and of a diminished vagal modulation. Although signs of sympathetic activation were more evident in patients with anterior wall AMI, no evidence of a vagal hyperactivity was observed in patients with inferior wall AMI. In the latter group, we noticed 1 week after the acute event an increase in the low-frequency component, which reached the values observed in patients with anterior wall AMI. Thrombolysis did not affect heart rate variability parameters. Thus, this study suggests the presence of an autonomic disturbance characterized by signs of sympathetic excitation and of a reduced vagal modulation, which was more evident in patients with an anterior localization early after AMI.