193 research outputs found

    Transcranial direct current stimulation improves the QT variability index and autonomic cardiac control in healthy subjects older than 60 years

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    Background: Noninvasive brain stimulation technique is an interesting tool to investigate the causal relation between cortical functioning and autonomic nervous system (ANS) responses. Objective: The objective of this report is to evaluate whether anodal transcranial direct current stimulation (tDCS) over the temporal cortex influences short-period temporal ventricular repolarization dispersion and cardiovascular ANS control in elderly subjects. Subjects and methods: In 50 healthy subjects (29 subjects younger than 60 years and 21 subjects older than 60 years) matched for gender, short-period RR and systolic blood pressure spectral variability, QT variability index (QTVI), and noninvasive hemodynamic data were obtained during anodal tDCS or sham stimulation. Results: In the older group, the QTVI, low-frequency (LF) power expressed in normalized units, the ratio between LF and high-frequency (HF) power, and systemic peripheral resistances decreased, whereas HF power expressed in normalized units and α HF power increased during the active compared to the sham condition (P,0.05). Conclusion: In healthy subjects older than 60 years, tDCS elicits cardiovascular and autonomic changes. Particularly, it improves temporal ventricular repolarization dispersion, reduces sinus sympathetic activity and systemic peripheral resistance, and increases vagal sinus activity and baroreflex sensitivity

    Possible predicative role of electrical risk score on transcatheter aortic valve replacement outcomes in older patients. preliminary data

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    Background:Transcatheter aortic valve replacement (TAVR) is an effective procedure capable to change the natural history of the degenerative aortic valve stenosis. Despite the TAVR, the patients with advanced valve disease and severe myocardial damage (low flow, gradient and ejection fraction)show high mortality level. Aim of this study was toevaluate the predicative power of a noninvasive and inexpensive test obtained by means of a simple standard 12-leads electrocardiogram,known as the Electrical Risk Score (ERS). Methods: ERS was composed by seven simple ECG markers: heart rate (>75 bpm); QRS duration (>110 ms), left ventricular hypertrophy (Sokolow-Lyon criteria), delayed QRS transition zone (≥ V4), frontal QRS-T angle (>90°), long QTBazett (>450 ms for men and >460 in women) or JTBazett(330 ms for men and > 340 ms for women);long T peak to T end interval (Tp-e)( >89 ms). An ERS ≥ 4was considered high risk for all-cause or cardiovascular mortality.We calculated retrospectively the pre-procedure ERS in 40 TAVR patients after one year of follow-up. Results: In the follow up the all-cause and cardiovascular mortality were respectively 25% and 15%.None of survivors reported ERS ≥ 4,moreover, the ERS was the strongest predictor of all-cause (odd ratio 3.73, 95% CI: 1.44-9.66, p<0.05) or cardiovascular (odd ratio 3.95, 95% CI: 1.09-14.27, p<0.05) mortality.ROC curves showed that ERS had the widest significant sensitivity-specificity area under the curve (auc) predicting all-cause (auc: 0.855, p<0.05) or cardiovascular mortality (auc: 0.908, p<0.05). Conclusions:In this pivotal study, ERS resulted an useful tool to stratify the risk of mortality in one-year follow-up TAVR patients. Obviously, it is necessary to confirm these data in large prospective studies

    Arrhythmic risk in elderly patients candidates to transcatheter aortic valve replacement. predicative role of repolarization temporal dispersion

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    Degenerative aortic valve stenosis (AS) is associated to ventricular arrhythmias and sudden cardiac death, as well as mental stress in specific patients. In such a context, substrate, autonomic imbalance as well as repolarization dispersion abnormalities play an undoubted role. Aim of the study was to evaluate the increase of premature ventricular contractions (PVC) and complex ventricular arrhythmias during mental stress in elderly patients candidate to the transcatheter aortic valve replacement (TAVR). In eighty-one elderly patients with AS we calculated several short-period RRand QT-derived variables at rest, during controlled breathing and during mild mental stress, the latter being represented by a mini-mental state evaluation (MMSE). All the myocardial repolarization dispersion markers worsened during mental stress (p &lt; 0.05). Furthermore, during MMSE, low frequency component of the RR variability increased significantly both as absolute power (LFRR) and normalized units (LFRRNU) (p &lt; 0.05) as well as the low-high frequency ratio (LFRR/HFRR) (p &lt; 0.05). Eventually, twenty-four (30%) and twelve (15%) patients increased significantly PVC and, respectively, complex ventricular arrhythmias during the MMSE administration. At multivariate logistic regression analysis, the standard deviation of QTend (QTesd), obtained at rest, was predictive of increased PVC (odd ratio: 1.54, 95% CI 1.14–2.08; p = 0.005) and complex ventricular arrhythmias (odd ratio: 2.31, 95% CI 1.40–3.83; p = 0.001) during MMSE. The QTesd showed the widest sensitive-specificity area under the curve for the increase of PVC (AUC: 0.699, 95% CI: 0.576–0.822, p &lt; 0.05) and complex ventricular arrhythmias (AUC: 0.801, 95% CI: 0.648–0.954, p &lt; 0.05). In elderly with AS ventricular arrhythmias worsened during a simple cognitive assessment, this events being a possible further burden on the outcome of TAVR. QTesd might be useful to identify those patients with the highest risk of ventricular arrhythmias. Whether the TAVR could led to a QTesd reduction and, hence, to a reductionof thearrhythmicburdenin thissettingofpatients isworthytobe investigated

    time and frequency domain analysis of beat to beat p wave duration pr interval and rr interval can predict asystole as form of syncope during head up tilt

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    To seek possible differences in short-period temporal RR interval, P-wave and PR interval dispersion and spectral coherence in patients with a head-up tilt test positive for vasovagal syncope with or without prolonged asystole, severe symptoms and at high risk of trauma. We retrospectively reviewed 5 min ECG and blood pressure recordings obtained at baseline, at rest and during head-up tilt in 40 patients diagnosed as having recurrent vasovagal syncope confirmed at a head-up tilt test. We analysed autoregressive spectral power for all the ECG-derived variables, focusing on temporal P-wave and PR interval dispersion indexes as well as their spectral coherence calculated on the same 5 min recordings at rest and during tilt. ECG recordings obtained during tilt before syncope showed significantly lower P → PR spectral coherence and higher RR standard deviations in patients with tilt-induced asystole than in those without (0.567 ± 0.097 versus 0.670 ± 0.127, p: 0.010 and 84 ± 36 versus 46 ± 22 ms2, p < 0.0001). Differences in the RR standard deviations persisted also on the last hundred beats (−100) (113 ± 54 versus 34 ± 17 ms2, p < 0.0001). Multiple regression analysis identified a significantly negative association between the maximum RR intervals and P → PR coherence at rest (β: −0.3, p < 0.05) and positive association with RR−100 standard deviation during tilt-induced syncope (β: 0.621, p < 0.001). P → PR spectral coherence could be used to assess the risk of prolonged asystole in patients with tilt-induced vasovagal syncope as well as as a possible surrogate for tilt-testing during these patients' follow-up

    Oscillatory behavior of P wave duration and PR interval in experimental congestive heart failure: a preliminary study

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    Objective: The relationship between the autonomic nervous system (ANS) modulation of the sinus node and heart rate variability has been extensively investigated. The current study sought to evaluate, in an animal experimental model of pacing-induced tachycardia congestive heart failure (CHF), a possible ANS influence on the P wave duration and PR interval oscillations. Approach: Short-term (5 min) time and frequency domain analysis has been obtained in six dogs for the following electrocardiographic intervals: P wave duration (P), from the onset to peak of P wave (P p), from the onset of P wave to the q onset (PR) and from the end of P wave to the onset of q wave (P e R). Direct vagal nerve activity (VNA), stellate ganglion nerve activity (SGNA) and electrocardiogram (ECG) intervals have been evaluated contextually by implantation of three bipolar recording leads. Main results: At the baseline, multiple regression analysis pointed out that VNA was strongly positively associated with the standard deviation of PP and P e R intervals (r 2:0.997, p < 0.05). The same variable was also positively associated with high-frequency (HF) of P expressed in normalized units, of P p, and of P e R (b: 0.001) (r 2: 0.993; p < 0.05). During CHF, most of the time and frequency domain variability significantly decreased from 20% to 50% in comparison to the baseline values (p < 0.05) and SGNA correlated inversely with the low frequency (LF) obtained from P e R (p < 0.05) and PR (p < 0.05) (r 2:0.899, p < 0.05). LF components, expressed in absolute and normalized power, obtained from all studied intervals, were reduced significantly during CHF. Any difference between the RR and PP spectral components was observed. Significance: The data showed a significant relationship between ANS and atrial ECG variables, independent of the cycle duration. In particular, the oscillations were vagal mediated at the baseline, while sympathetic mediated during CHF. Whereas P wave variability might have a clinical utility in CHF management, it needs to be addressed in specific studies

    QT interval variability in body surface ECG: measurement, physiological basis, and clinical value: position statement and consensus guidance endorsed by the European Heart Rhythm Association jointly with the ESCWorking Group on Cardiac Cellular Electrophysiology

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    This consensus guideline discusses the electrocardiographic phenomenon of beat-to-beat QT interval variability (QTV) on surface electrocardiograms. The text covers measurement principles, physiological basis, and clinical value of QTV. Technical considerations include QT interval measurement and the relation between QTV and heart rate variability. Research frontiers of QTV include understanding of QTV physiology, systematic evaluation of the link between QTV and direct measures of neural activity, modelling of the QTV dependence on the variability of other physiological variables, distinction between QTV and general T wave shape variability, and assessing of the QTV utility for guiding therapy. Increased QTV appears to be a risk marker of arrhythmic and cardiovascular death. It remains to be established whether it can guide therapy alone or in combination with other risk factors. QT interval variability has a possible role in non-invasive assessment of tonic sympathetic activity

    Electrocardiographic and other noninvasive hemodynamic markers in decompensated CHF patients

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    cutely decompensated chronic heart failure (adCHF) is among the most important causes of in-hospital mortality. R-wave peak time (RpT) or delayed intrinsicoid deflection was proposed as a risk marker of sudden cardiac death and heart failure decompensation. Authors want to verify if QR interval or RpT, obtained from 12-lead standard ECG and during 5-min ECG recordings (II lead), could be useful to identify adCHF. At hospital admission, patients underwent 5-min ECG recordings, obtaining mean and standard deviation (SD) of the following ECG intervals: QR, QRS, QT, JT, and T peak–T end (Te). The RpT from a standard ECG was calculated. Patients were grouped by the age-stratified Januzzi NT-proBNP cut-off. A total of 140 patients with suspected adCHF were enrolled: 87 (mean age 83 ± 10, M/F 38/49) with and 53 (mean age: 83 ± 9, M/F: 23/30) without adCHF. V5-, V6- (p &lt; 0.05) RpT, and QRSD, QRSSD, QTSD, JTSD, and TeSD p &lt; 0.001 were significantly higher in the adCHF group. Multivariable logistic regression analysis demonstrated that the mean of QT (p &lt; 0.05) and Te (p &lt; 0.05) were the most reliable markers of in-hospital mortality. V6 RpT was directly related to NT-proBNP (r: 0.26, p &lt; 0.001) and inversely related to a left ventricular ejection fraction (r: 0.38, p &lt; 0.001). The intrinsicoid deflection time (obtained from V5-6 and QRSD) could be used as a possible marker of adCHF

    Gefitinib in Non Small Cell Lung Cancer

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    Gefitinib is an oral, reversible, tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) that plays a key role in the biology of non small cell lung cancer (NSCLC). Phase I studies indicated that the recommended dose of gefitinib was 250 mg/day. Rash, diarrhea, and nausea were the most common adverse events. The positive results obtained in early phase 2 clinical trials with gefitinib were not confirmed in large phase 3 trials in unselected patients with advanced NSCLC. The subsequent discovery that the presence of somatic mutations in the kinase domain of EGFR strongly correlates with increased responsiveness to EGFR tyrosine kinase inhibitors prompted phase 2 and 3 trials with gefitinib in the first line-treatment of EGFR-mutated NSCLC. The results of these trials have demonstrated the efficacy of gefitinib that can be now considered as the standard first-line treatment of patients with advanced NSCLC harbouring activating EGFR mutations

    Sex Differences in Repolarization Markers: Telemonitoring for Chronic Heart Failure Patients

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    Unlabelled: Aging and chronic heart failure (CHF) are responsible for the temporal inhomogeneity of the electrocardiogram (ECG) repolarization phase. Recently, some short period repolarization-dispersion parameters have been proposed as markers of acute decompensation and of mortality risk in CHF patients. Some important differences in repolarization between sexes are known, but their impact on ECG markers remains unstudied. The aim of this study was to evaluate possible differences between men and women in ECG repolarization markers for the telemonitoring of CHF patients. Method: 5 min ECG recordings were collected to assess the mean and standard deviation (SD) of the following variables: QT end (QTe), QT peak (QTp), and T peak to T end (Te) in 215 decompensated CHF (age range: from 49 to 103 years). Thirty-day mortality and high levels of NT-pro BNP (&lt;75 percentile) were considered markers of decompensated CHF. Results: A total of 34 patients (16%) died during the 30-day follow-up, without differences between sexes. Women showed a more preserved ejection fraction and higher LDL and total cholesterol levels. Among female patients, implantable cardioverter devices, statins, and antiplatelet agents were less used. Data for Te mean showed increased values among deceased men and women compared to survival, but TeSD was shown to be the most reliable marker for CHF reacutization in both sexes. Conclusion: TeSD could be considered a risk factor for CHF worsening and complications for female and male patients, but different cut offs should be taken into account. (ClinicalTrials.gov number, NCT04127162.)
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