Annabella Braschi

Influence of climatic variables on acute myocardial infarction hospital admissions

BACKGROUND Seasonal peaks in acute myocardial infarction (AMI) incidence have been widely reported. Weather has been postulated to be one of the elements at the basis of this association. The aim of our study was to determine the influence of seasonal variations and weather on AMI hospital admissions. METHODS We correlated the daily number of AMI cases admitted to a western Sicily hospital over twelve years and weather conditions on a day-to-day basis. Information on temperature, humidity, wind force and direction, precipitation, sunny hours and atmospheric pressure was obtained from the local Birgi Air Force base. A total of 3918 consecutive patients were admitted with AMI over the period 1987-1998 (2822 men, 1096 women; M/F: 2,58). RESULTS AND CONCLUSIONS A seasonal variation was found with a significant winter peak. The results of multivariate Poisson analysis show in both sexes a significant association as regards the incidence relative ratio between the daily number of AMI hospital admission and minimal daily temperature and maximal daily humidity. The incidence relative ratios (95% confidence intervals) were, in males, 0.95 (0.92-0.98) (p<0.001) as regards minimal temperature and 0.97 (0.94-0.99) (p=0.017) as regards maximal humidity. The corresponding values in females were respectively 0.91 (0.86-0.95) (p<0.001) and 0.94 (0.90-0.98) (p=0.009). Environmental temperature, and also humidity, may play an important role in the pathogenesis of AMI. These data may help in understanding the mechanisms whereby AMI events are triggered and in organizing better the assistance to ischemic patients throughout the year.

Effects of Nebivolol versus Carvedilol on Left Ventricular Function in Patients with Chronic Heart Failure and Reduced Left Ventricular Systolic Function

Backgroundβ-Adrenoceptor antagonist (β-blocker) therapy results in a significant improvement in left ventricular (LV) systolic function and prognosis in patients with chronic heart failure. Both carvedilol and nebivolol produce hemodynamic and clinical benefits in chronic heart failure, but it is unknown whether their peculiar pharmacologic properties produce different effects on LV function.ObjectiveTo assess the effects on LV function of nebivolol compared with carvedilol in patients with chronic heart failure and reduced LV systolic function.MethodsSeventy patients with a LV ejection fraction ≤40% and in New York Heart Association (NYHA) functional class II or III were randomly assigned to receive carvedilol or nebivolol therapy for 6 months. At baseline and after 6 months of treatment, all patients were assessed clinically and by biochemical and hematological investigation, ECG, 24-hour Holter monitoring, echocardiogram, measurement of ventilatory function, and a 6-minute walk test.ResultsCompared with baseline values LV end-systolic volume decreased and LV ejection fraction increased in both the carvedilol (from 79 ± 38mL to 73 ± 43mL and from 33% ± 6% to 37% ± 11%) and the nebivolol group (from 72 ± 35mL to 66 ± 32mL and from 34% ± 7% to 38% ± 10%), although the between-group differences were not statistically significant. ECG data showed a decrease in resting HR in both groups (from 83 ± 20 bpm to 66 ± 11 bpm for carvedilol and from 81 ± 15 bpm to 65 ± 11 bpm for nebivolol; p < 0.001 vs baseline for both groups) but no difference in the PQ, QRS, and QT intervals. Hematologic (in particular, N-terminal pro-brain natriuretic peptide), Holter monitoring (with the exception of HR), and respiratory functional data did not show any significant variation in either group after 6 months’ therapy. SBP and DBP decreased in both groups. A small reduction in mean NYHA functional class from baseline was seen in both groups (from 2.5 ± 0.5 to 2.2 ± 0.5 for carvedilol [p < 0.05] and from 2.3 ± 0.4 to 2.2 ± 0.5 for nebivolol [not significant]). The 6-minute walk test showed a trend toward an increase in the walking distance in both groups. During 6 months of treatment no significant differences in adverse events were observed between the groups.ConclusionNebivolol is as effective as carvedilol in patients with symptomatic chronic heart failure and reduced LV systolic function.

Effects of ambient temperature, humidity, and other meteorological variables on hospital admissions for angina pectoris

Background: Seasonal peaks in cardiovascular disease incidence have been widely reported, suggesting weather has a role. Design The aim of our study was to determine the influence of climatic variables on angina pectoris hospital admissions. Methods: We correlated the daily number of angina cases admitted to a western Sicilian hospital over a period of 12 years and local weather conditions (temperature, humidity, wind force and direction, precipitation, sunny hours and atmospheric pressure) on a day-to-day basis. A total of 2459 consecutive patients were admitted over the period 1987–1998 (1562 men, 867 women; M/F – 1:8). Results: A seasonal variation was found with a noticeable winter peak. The results of Multivariate Poisson analysis showed a significant association between the daily number of angina hospital admission, temperature, and humidity. Significant incidence relative ratios (95% confidence intervals/measure unit) were, in males, 0.988 (0.980–0.996) (p = 0.004) for minimal temperature, 0.990 (0.984–0.996) (p = 0.001) for maximal humidity, and 1.002 (1.000–1.004) (p = 0.045) for minimal humidity. The corresponding values in females were 0.973 (0.951–0.995) (p < 0.017) for maximal temperature and 1.024 (1.001–1.048) (p = 0.037) for minimal temperature. Conclusions: Environmental temperature and humidity may play an important role in the pathogenesis of angina, although it seems different according to the gender. These data may help to understand the mechanisms that trigger ischemic events and to better organize hospital assistance throughout the year.

Novel Electrocardiographic Parameters of Altered Repolarization in Uncomplicated Overweight and Obesity

In addition to well‐known electrocardiographic measurements, as QT, QT dispersion, and QT apex dispersion, new parameters such as Tpeak‐Tend, Tpeak‐Tend dispersion, and Tpeak‐Tend/QT ratio have been recently introduced as indexes of increased arrhythmic risk. The aim of the present study was to test, in overweight and obese subjects not affected by conditions of comorbidity, the aforementioned markers of ventricular repolarization. We studied 60 athletic subjects with normal body weight (21 females and 39 males, BMI between 19 and 24, mean BMI 22.0 ± 2.0 kg/m2, aged 14–64 years, mean age 32 ± 13.59) and 60 sedentary and overweight/obese subjects (34 overweight and 26 obese, 22 females, and 38 males, BMI between 26 and 55, mean BMI 30.7 ± 5.7 kg/m2, aged 14–64, mean age 38 ± 14.49). Each subject underwent anthropometric measurements and a 12‐lead electrocardiogram, from which the following different parameters were calculated: QT, corrected QT, QT dispersion, QT apex dispersion, Tpeak‐Tend, Tpeak‐Tend dispersion and Tpeak‐Tend/QT ratio were calculated. The aforementioned repolarization markers resulted, respectively: 340.2 ± 25.1, 373.8 ± 25.9, 29 ± 16.2, 23.5 ± 14.6, 87.3 ± 12.8, 26.5 ± 16.8, and 0.22 ± 0.03 ms in control subjects and 362.5 ± 28.5, 397.4 ± 35.4, 34.5 ± 16.8, 30.7 ± 16.3, 90.5 ± 15.2, 27 ± 17.1, and 0.22 ± 0.04 ms in overweight/obese subjects. Neither uncomplicated obesity nor overweight were associated with a statistically significant difference in QT dispersion, QT apex dispersion, Tpeak‐Tend, Tpeak‐Tend dispersion, and Tpeak‐Tend/QT ratio; QT and corrected QT were the only parameters that showed statistically significant variations between normal weight and overweight/obese subjects.

Behavior of repolarization variables during exercise test in the athlete's heart.

Background: T peak–T end, QT peak/QT ratio and T peak–T end/QT ratio are markers able to test myocardial repolarization homogeneity, their increase has been related to a higher risk of ventricular tachyarrhythmias. These parameters have not yet been studied in left ventricular hypertrophy due to training. Aim of the research was to test the behavior of these variables in the athletes heart during exercise.

Age- and sex-based reference ranges for non-invasive ventricular repolarisation parameters

Some electrocardiographic parameters are able to assess indirectly ventricular repolarisation homogeneity. It is consequently essential to discriminate between normal and abnormal values in clinical decision‐making. Considering there is still not a consensus about normal cut‐off values, the aim of this study was to document reference intervals in all age groups of a healthy population, providing for age‐ and sex‐percentile tables, which can be used easily and quickly in clinical practice.

INTRAHOSPITAL COMPLICATIONS OF ACUTE MYOCARDIAL INFARCTION IN HYPERTENSIVE PATIENTS. A RETROSPECTIVE CASE-CONTROL STUDY: P1.221

Recent clinical trials described in AMI a poorer in-hospital prognosis of hypertensives (H) in comparison to normotensives (NT) due to more prevalent ischaemic, arrhythmic, and functional complications. However, H pts are more often of female sex and advanced age than NT ones, and the negative prognostic impact of these factors is well known. Aim of the present study was to evaluate the clinical patterns concomitant diseases and risk factors, and the in-hospital complications in H pts with AMI. From our database of 3924 patients consecutively admitted to our I.C.C.U., over the period 1987–1998, we selected 791 pts with history hypertension, 433 males and 358 females, mean age 69,1 6 9,3 years. As control group we evaluated 791 NT pts coupled for sex and age. It was not found any significant difference between controls and H, as regards the site of AMI, but the last group had a significantly (p , 0,01) higher number of ST depression at the entry (65.2 vs 42.3%) and of non Q wave AMI (83.5 vs 37.8%), as well as of previous AMI (32.1 vs 23.5%), diabetes (7.8 vs 5.2%), renal failure (4.4 vs 1.2%), peripheral arterial disease (2.7 vs 1.1%), dyslipidemia (33.3 vs 21.8%), CVD (3.9 vs 1.6%) and chronic obstructive lung disease (8.6 vs 4.4%). As regards in-hospital complications, H pts showed a significantly higher prevalence of post-AMI angina (9.9 vs 7.6%, p , 0.05), silent myocardial ischemia (1.4 vs 0.6%, p , 0.01) and paroxysmal AF (7.1 vs 3.8%, p , 0.01) as well as a significantly lower prevalence of deaths (5.2 vs 13.7%, p,0.01), cardiogenic shock (2.9 vs 8.6%, p ,0.01), A-V block (3.3 vs 5.1%, p , 0.05) and VT and VF (3.2 vs 4.5%, p , 0,05). No significant difference has been found in LV failure, reinfarction, endoventricular thrombosis, pericarditis or concomitant stroke between the 2 groups. We conclude that H patients with AMI, when excluding confounding factors such as sex and age, show a better in-hospital prognosis than NT perhaps due to a less severe extension of the infarctual area and to the different pathophysiological pattern.