Residual congestion and long-term prognosis in acutely decompensated heart failure patients.

AIMS: Recent studies have established the role of residual congestion evaluated by lung ultrasound in estimating short-term risk of readmission or death in patients admitted for heart failure (HF) decompensation. However, if lung ultrasounds maintain a prognostic role of in long-term survival is still unknown. Aim of our study was to evaluate if residual congestion could predict all-cause mortality during 4 year follow up in a cohort of unselected patients admitted for acute decompensated HF. METHODS: One-hundred fifty patients were enrolled. The anterolateral chest was scanned to evaluate the presence of B-lines. A sonographic score was calculated attributing 1 to each positive sector (≥ 3 B-lines). Clinical, biochemical and echocardiographic data were recorded. A Cox proportional hazard regression analysis was performed to evaluate the association between variables and 4-year survival. RESULTS: During the follow-up, 86 patients (58%) died. Univariate analysis showed a significant correlation between the sonographic score at discharge and events occurrence at long term follow up (HR 1.21; CI 1.11-1.31; p < 0.001) suggesting that, on average, the increase of 1 point in the sonographic score was associated with an increase of approximately 20% in the risk of death. CONCLUSIONS: Our results suggest the role of LUS in the identification of more congested HF patients, that will be at risk for worse long term outcome.

Lung ultrasonography in pulmonary tuberculosis: A pilot study on diagnostic accuracy in a high-risk population.

OBJECTIVES: The validity of lung ultrasound (LUS) in the diagnosis of interstitial or focal lung pathologies is well documented, we assessed its accuracy in the diagnosis of pulmonary tuberculosis (PTB). METHODS: Sonographic signs suggestive of PTB and their diagnostic accuracy were evaluated in patients admitted with clinical suspicion of PTB. Consolidations, subpleural nodules, pleural thickenings or irregularities and pleural effusion were assessed. LUS signs significantly associated with PTB in the univariate analysis (p < .05) were entered in a multivariate logistic regression model. RESULTS: PTB was confirmed in 51 out of 102 patients. Multiple consolidations (OR 3.54, 95%CI 1.43-8.78), apical consolidations (OR 9.65, 95%CI 3.02-30.78), superior quadrant consolidations (OR 4.01, 95%CI 1.76-9.14), and subpleural nodules (OR 5.29, 95%CI 2.27-12.33) were significantly associated with PTB diagnosis. Apical consolidation (OR 9.67, 95%CI 2.81-33.25, p 0.003) and subpleural nodules (OR 5.30, 95%CI 2.08-13.52, p 0.005) retained a significant association in a multivariate model, with an overall accuracy of 0.799. CONCLUSIONS: Our data suggest a possible role of LUS in the diagnosis of PTB, a high burden pathological condition for which the delay in diagnosis still represents a critical point in the control of the disease.

Chagas disease knocks on our door: a cross-sectional study among Latin American immigrants in Milan, Italy.

OBJECTIVES: We aimed to assess the prevalence and risk factors for Chagas disease (CD) in Latin American immigrants and to evaluate the accuracy of diagnostic tests. Moreover, we offered to all positive subjects a complete free-of-charge clinical/instrumental evaluation as well as benznidazole treatment in order to stage the disease and verify drug tolerability. METHODS: A cross-sectional survey of CD among Latin Americans living in Milan and its metropolitan area was conducted between July 2013 and July 2014. Blood samples were tested for serologic evidence of CD together with a questionnaire covering demographic and clinical-epidemiological information. RESULTS: Forty-eight (9.6%) of the 501 tested subjects were conclusively diagnosed as having CD. The highest prevalence of CD was among those from Bolivia (43/169, 25.4%) and El Salvador (4/68, 5.9%). Older age (adjusted odds ratio (aOR)] 1.05, p =0.004), a Bolivian origin (aOR 8.80; p =0.003), being born in the department of Santa Cruz (aOR 3.72, p =0.047), having lived in mud houses (aOR 2.68; p =0.019), and having an affected relative (aOR 12.77, p =0.001) were independently associated with CD. The ARCHITECT Chagas test showed the highest sensitivity (100%) and specificity (99.8%). Twenty-nine of the subjects with CD (60.4%) underwent disease staging, 10 of whom (35.7%) showed cardiac and/or digestive involvement. Benznidazole treatment was associated with high frequency of adverse reactions (19/27, 70.4%) and permanent discontinuation (8/27, 29.6%). CONCLUSIONS: CD is highly prevalent among Bolivians and Salvadorans living in Milan. Regions with a large Latin American immigrant population should implement programmes of active detection and treatment.

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.

Effects of beta blockers (atenolol or metoprolol) on heart rate variability after acute myocardial infarction.

This study analyzed, with spectral techniques, the effects of atenolol or metoprolol on RR interval variability in 20 patients 4 weeks after the first uncomplicated myocardial infarction. Beta blocker-induced bradycardia was associated with a significant increase in the average 24-hour values of RR variance (from 13,886 +/- 1,479 to 16,728 +/- 1,891 ms2) and of the normalized power of the high-frequency component (from 22 +/- 1 to 28 +/- 2 normalized units), whereas the low-frequency component was greatly reduced (from 60 +/- 3 to 50 +/- 3 normalized units). When considering day and nighttime separately, the effects of both drugs were more pronounced in the daytime. In addition, a marked attenuation was observed in the circadian variation of the low-frequency component after beta blockade. As a result, the early morning increase of the spectral index of sympathetic modulation was no longer detectable. These results indicate that beta-blocker administration has important effects on RR interval variability and on its spectral components. The observed reduction in signs of sympathetic activation and the increase in vagal tone after beta blockade help to explain the beneficial effects of these drugs after myocardial infarction. However, the potential clinical relevance of the increase in RR variance remains to be established.

Beta-blocking effect of propafenone based on spectral analysis of heart rate variability.

RR variability was analyzed in 15 patients with ventricular arrhythmias to evaluate whether the antiarrhythmic action of propafenone is associated with alteration of neural control mechanisms. Before drug administration, spectral analysis of RR variability was characterized by 2 major components at low and high frequency, which are considered to reflect sympathetic and parasympathetic modulation of the heart period. After propafenone (600 to 900 mg/day), there was a marked reduction in RR variance (826 +/- 184 to 412 +/- 77 ms2; p < 0.05), although the mean RR interval was unchanged. The drug significantly reduced the low-frequency component (52 +/- 6 to 28 +/- 4 nu) and augmented the high-frequency component (39 +/- 6 to 55 +/- 5 nu). As a result, the low-/high-frequency ratio (an index of sympathovagal balance) decreased from 2.0 +/- 0.4 to 0.6 +/- 0.1. A positive correlation between serum levels and drug-induced changes in the low-frequency component was also observed. Furthermore, the increase in the low-frequency component induced by tilt (53 +/- 5 to 79 +/- 3 nu) was markedly attenuated after drug administration (27 +/- 5 to 54 +/- 7 nu). Thus, propafenone administration is associated with changes in spectral components that are consistent with a beta-blocking effect of the drug.

Linear and nonlinear dynamics of heart rate variability after acute myocardial infarction with normal and reduced left ventricular ejection fraction.

We analyzed heart rate variability (HRV) in 2 groups of patients after acute myocardial infarction with normal and reduced ejection fraction (EF) by considering both the power of the 2 major harmonic components at low and high frequency and 2 indexes of nonlinear dynamics, namely the 1/f slope and the correlation dimension D2. HRV of patients with a reduced EF was characterized by a diminished RR variance as well as a different distribution of the residual power in all frequency ranges, with lower values of the low-frequency component expressed in both absolute and normalized units, and of the low- to high-frequency ratio. In these patients we also observed a steeper slope of the negative regression line between power and frequency in the very low frequency range. The presence of a smaller fractal dimension was suggested by a lower D2. Thus, in patients after acute myocardial infarction with a reduced EF, the reduction in HRV is associated with a different distribution of the residual power in the entire frequency range, which suggests a diminished responsiveness of sinus node to neural modulatory inputs.

Spectral analysis of short term R-Tapex interval variability during sinus rhythm and fixed atrial rate.

Analysis of heart rate variability has been proven useful in stratifying post myocardial patients at risk and in evaluating autonomic dysfunction. Recently augmented inter-lead variability of the QT interval has been associated with increased mortality as a result of arrhythmia and proposed as a marker of dispersion of ventricular repolarization. As the duration of the QT interval is largely dependent upon the length of the preceding cardiac cycle it is tempting to analyse whether neural mechanisms might also directly exert additional modulation. Using autoregressive algorithms we therefore analysed RR and R-Tapex interval variabilities in 15 normal subjects during sinus rhythm and in six patients with a fixed atrial rate. In controls mean R-Tapex interval and variance measured on the vector magnitude were, respectively, 245 +/- 6 ms and 5.1 +/- 0.7 ms2. Spectral analysis of R-Tapex indicated the presence of two spectral components which corresponded to the low and high frequency components of heart rate variability. In R-Tapex variability, high frequency (44 +/- 4 nu) was predominant over low frequency (29 +/- 4 nu). During controlled respiration, a manoeuvre associated with enhanced vagal modulation of sinus node, there was a further increase in high frequency (58 +/- 4 nu) whereas during tilt the low frequency component of R-Tapex variability became predominant (57 +/- 6 nu). In patients with a fixed atrial rate, variance was extremely low (3 +/- 0.9 ms2) and only a respiration-related high frequency component was recognizable in spectral analysis of RR and R-Tapex variabilities. This component was likely to depend upon mechanically induced changes in cardiac vector orientation. These data indicate that during sinus rhythm short-term R-Tapex interval variability is characterized by the same rhythmical components present in RR variability. However, the presence of a very low variance and of only a high frequency component in patients in whom the physiological variability of sinus node is abolished by atrial pacing. suggests that neural modulatory mechanisms do not exert a direct effect on the length of the R-Tapex interval.

Evidence of functional alterations in sympathetic activity after myocardial infarction.

To assess whether the presence of areas of efferent sympathetic denervation might contribute to alterations in sympathetic and vagal neural regulatory activities observed after myocardial infarction, we attempted to correlate the changes in the spectral components of RR variability with the I-123 MIBG and Thallium-201 uptake defects. Ten patients with first and uncomplicated myocardial infarction were studied. Thallium-201 and I-123 MIBG scintigraphy as well as spectral analysis of heart rate variability were performed 7 days, 4, 12 and 30 months after the acute event. Regional abnormalities in I-123 MIBG uptake were more extensive than the perfusion defects indicated by Thallium-201 images and remained constant throughout the entire period of observation. In the early post-infarction period, spectral analysis of RR variability was characterized by a predominant LF (74 +/- 6 nu) and a smaller HF (16 +/- 3 nu) component indicating a sympathetic predominance. Thereafter, we observed a progressive reduction in LF and a gradual increase in HF which were consistent with a normalization of sympatho-vagal balance. These data indicate that after a myocardial infarction, the presence and persistence of areas of sympathetic functional denervation do not seem to play a major role in determining the changes in sympathetic and vagal neural regulatory activities directed to the heart.