Low-voltage Pattern Research Articles

The Most Predictive Red Flags for Suspecting Cardiac Amyloidosis in Patients with Heart Failure with Preserved Ejection Fraction.

Cardiac amyloidosis (CA) is a cardiomyopathy characterized by amyloid infiltration in the myocardium. Transthyretin cardiac amyloidosis (TTR-CA), commonly presenting as heart failure with preserved ejection fraction (HFpEF), was the focus of our study, which aimed to identify red flags that heighten suspicion of CA in HFpEF patients. We prospectively included patients diagnosed with HFpEF. All patients were assessed for TTR-CA red flag features, cardiac and extra-cardiac, as outlined in the 'Diagnosis and Treatment of Cardiac Amyloidosis: A Position Statement of the European Society of Cardiology.' Technetium-99m pyrophosphate (99mTc-PYP) cardiac scintigraphy was performed in 167 HFpEF patients suspected of having TTR-CA. Patients testing positive and negative for TTR-CA were compared based on these red flag features. Out of 167 HFpEF patients, 19 (11.3%) were diagnosed with TTR-CA. In the TTR-CA group, 17 (89.5%) patients were 65 years or older. The presence of three or more red flags differentiated the TTR-CA positive and negative groups (P = 0.040). Features such as low voltage and pseudo infarct patterns were more prevalent in the TTR-CA group (P < 0.001 and P < 0.048, respectively). Left ventricular global longitudinal strain (LV-GLS) was lower in the TTR-CA positive group (P < 0.001). Multivariate analysis identified four variables-older age, pseudo infarct pattern, low/decreased QRS voltage, and LV-GLS-as strong, independent predictors of TTR-CA, with significant odds ratios (ORs) of 7.8, 6.8, 16.9, and 1.2, respectively. In this study, TTR-CA etiology occurs in approximately one in every ten HFpEF patients. The presence of three or more red flags increases the likelihood of TTR-CA. Older age, pseudo infarct pattern, low/decreased QRS voltage, and reduced LV-GLS are the most significant red flags indicating TTR-CA in HFpEF patients.

Postdevelopment Performance and Validation of the Artificial Intelligence-Enhanced Electrocardiogram for Detection of Cardiac Amyloidosis

BackgroundWe have previously applied artificial intelligence (AI) to an electrocardiogram (ECG) to detect cardiac amyloidosis (CA). ObjectivesIn this validation study, the authors observe the postdevelopment performance of the AI-enhanced ECG to detect CA with respect to multiple potential confounders. MethodsAmyloid patients diagnosed after algorithm development (June 2019-January 2022) with a 12-lead ECG were identified (n = 440) and were required to have CA. A 15:1 age- and sex-matched control group was identified (n = 6,600). Area under the receiver operating characteristic (AUC) was determined for the cohort and subgroups. ResultsThe average age was 70.4 ± 10.3 years, 25.0% were female, and most patients were White (91.3%). In this validation, the AI-ECG for amyloidosis had an AUC of 0.84 (95% CI: 0.82-0.86) for the overall cohort and between amyloid subtypes, which is a slight decrease from the original study (AUC 0.91). White, Black, and patients of “other” races had similar algorithm performance (AUC >0.81) with a decreased performance for Hispanic patients (AUC 0.66). Algorithm performance shift over time was not observed. Low ECG voltage and infarct pattern exhibited high AUC (>0.90), while left ventricular hypertrophy and left bundle branch block demonstrated lesser performance (AUC 0.75 and 0.76, respectively). ConclusionsThe AI-ECG for the detection of CA maintained an overall strong performance with respect to patient age, sex, race, and amyloid subtype. Lower performance was noted in left bundle branch block, left ventricular hypertrophy, and ethnically diverse populations emphasizing the need for subgroup-specific validation efforts.

Electrocardiographic features and need for pacemaker in cardiac amyloidosis: Analysis of 58 cases

AimAmyloidosis is a disease in which amyloid fibrils can be deposited in different cardiac structures, and several electrocardiographic abnormalities can be produced by this phenomenon. The objective of this study was to describe the most common basal electrocardiographic alterations in patients diagnosed with cardiac amyloidosis (CA) and to determine if these abnormalities have an impact on the need of pacemaker. MethodsThis retrospective study included patients who had an established diagnosis of CA [light-chain cardiac amyloidosis (LA-CA) or transthyretin cardiac amyloidosis (TTR-CA)] between January 2013 and March 2021. The baseline heart rate, the percentage of patients with a pseudo-infarct pattern, low-voltage pattern or cardiac conduction disturbances, and the impact of these factors on the need of pacemaker were analysed. ResultsFifty-eight patients with CA (20 with LA-CA and 38 with TTR-CA) were included, and the majority were male (69.0%). Twenty-one patients had atrial fibrillation (AF) at diagnosis. Thirty-five patients had a pseudo-infarct pattern, 35% had a low-voltage pattern, and 22% had criteria for ventricular hypertrophy. Two hirds had a conduction disorder: 18 patients with first degree atrioventricular block, 12 right bundle branch block, 3 left bundle branch block and 25 with a branch hemiblock. There were no differences between LA-CA and TTR-CA. Patients with TTR-CA had a greater need for pacemakers in the follow-up (39 ± 40 meses). Bundle branch block was a predictor of the need for a permanent pacemaker (HR 23.43, 4.09–134.09, IC 95%, p = 0.01). ConclusionsElectrocardiographic abnormalities in patients diagnosed wich CA are heterogeneus. Most frecuent is the presence of conduction disorders, the pseudoinfarction pattern, followed by the low voltage pattern. Patients with any bundle branch block at the baseline electrocardiogram need more frecuent to require a pacemaker during follow-up, especially in TTR-CA.

Clinical Profile and Prognosis of Hereditary Transthyretin Amyloid Cardiomyopathy: A Single-Center Study in South China.

BackgroundHereditary transthyretin amyloid cardiomyopathy (ATTR-CM) is a genotypically heterogeneous disorder with a poor prognosis. There is limited literature describing the variants responsible for ATTRv in areas outside the United State, the United Kingdom and Europe. This study was performed to describe the clinical characteristics and genotypic profiles of this disease in South China.MethodsThis was a single-center retrospective study that evaluated 29 patients with a confirmed diagnosis of hereditary transthyretin amyloid cardiomyopathy enrolled from January 2016 to November 2021.Results93.1% patients were male and the median age of symptom onset was 53 (46, 62.5) years old. The initial manifestations of ATTR-CM were cardiovascular symptoms (55.2%), neuropathy (41.4%) and vitreous opacity (3.4%). Phenotypes at diagnosis were mixed (82.8%), predominant cardiac (6.9%), neurological (6.9%) and ophthalmic (3.4%). Poor R-wave progression (41%), pseudo-infarct (31%) and low-voltage (31%) patterns were common findings on electrocardiogram. Unexplained increased wall thickness was observed in all 29 patients, with mean septal and posterior wall thicknesses of 14.25 ± 6.26 mm and 15.34 ± 2.84 mm, respectively. Diastolic dysfunction was also seen in all 29 patients, and 17 (58%) had a restrictive fill pattern at diagnosis. Nine different missense mutations of the TTR gene were found in 29 patients from 23 families, with c.349G>T (p.Ala117Ser) the most common mutation. The median survival time after diagnosis was 47.6 (95% CI 37.9-57.4) months, with 1, 3 and 5-year survival rates of 91.2%, 74% and 38% respectively. Patients with advanced heart failure (National Amyloidosis Staging stage II/III) had worse survival than stage I [Breslow (Generalized Wilcoxon), χ2 = 4.693, P = 0.03)].ConclusionsATTR amyloidosis genotypes and phenotypes are highly heterogeneous. Advanced heart failure predicts a poor prognosis. Understanding the different clinical profiles of ATTR cardiac amyloidosis with different genotype is important to its early recognition.

Effect of doxapram on the electrical activity of the diaphragm waveform pattern of preterm infants.

This study aimed to evaluate the change in the waveform pattern of the electrical activity of the diaphragm (Edi) following the administration of doxapram in extremely preterm infants ventilated with neurally adjusted ventilatory assist (NAVA). We conducted this retrospective cohort study in our neonatal intensive care unit between November 2019 and September 2021. The study participants were extremely preterm infants under the gestational age of 28 weeks who were ventilated with NAVA and administered doxapram. We collected the data of the Edi waveform pattern and calculated the proportion. To analyze the change in the proportion of the Edi waveform pattern, we compared the proportion of the data for 1 h before and after doxapram administration. Ten extremely preterm infants were included. Almost all the patients' respiratory condition improved after doxapram administration. The ventilatory parameters-Edi peak, Edi minimum, peak inspiratory pressure, time in backup ventilation, and number of switches to backup ventilation-did not change significantly. However, the proportion of phasic pattern significantly increased (before: 46% vs. after: 72%; p < 0.05), whereas the central apnea pattern significantly decreased after doxapram administration (before: 31% vs. after: 8.3%; p < 0.05). The proportion of irregular low-voltage patterns tended to decrease, albeit with no significant changes. Our results indicated that the proportion of Edi waveform patterns changed following doxapram administration. Edi waveform pattern analysis could be a sensitive indicator of effect with other intervention for respiratory conditions.

Alteraciones electrocardiográficas y necesidad de marcapasos en amiloidosis cardiaca: análisis de 58 casos

AimAmyloidosis is a disease in which amyloid fibrils can be deposited in different cardiac structures, and several electrocardiographic abnormalities can be produced by this phenomenon. The objective of this study was to describe the most common basal electrocardiographic alterations in patients diagnosed with cardiac amyloidosis (CA) and to determine if these abnormalities have an impact on the need of pacemaker. MethodsThis retrospective study included patients who had an established diagnosis of CA [light-chain cardiac amyloidosis (LA-CA) or transthyretin cardiac amyloidosis (TTR-CA)] between January 2013 and March 2021. The baseline heart rate, the percentage of patients with a pseudo-infarct pattern, low-voltage pattern or cardiac conductions disturbances, and the impact of these factors on the need of pacemaker were analysed. ResultsFifty-eight patients with CA (20 with LA-CA and 38 with TTR-CA) were included, and the majority were male (69.0%). Twenty-one patients had atrial fibrillation (AF) at diagnosis. Thirty-five patients had a pseudo-infarct pattern, 35% had a low-voltage pattern, and 22% had criteria for ventricular hypertrophy. Two hirds had a conduction disorder: 18 patients with first degree atrioventricular block, 12 right bundle branch block, 3 left bundle branch block and 25 with a branch hemiblock. There were no differences between LA-CA and TTR-CA. Patients with TTR-CA had a greater need for pacemakers in the folow-up (39±40 meses). Bundle branch block was a predictor of the need for a permanent pacemaker (HR: 23.43; CI 95%: 4.09.134.09; P=.01). ConclusionsElectrocardiographic abnormalities in patients diagnosed wich CA are heterogeneus. Most frecuent is the presence of conduction disorders, the pseudoinfarction pattern, followed by the low voltage pattern. Patients with any bundle branch block at the baseline electrocardiogram need more frecuent to require a pacemaker during follow-up, especially in TTR-CA.

Use of lung ultrasound and and aEEG patterns to predict the need for mechanical ventilation and the readiness for extubation in neonates with respiratory distress

Objective. The aim of the study was to establish if lung ultrasound findings could anticipate the need for intubation and mechanical ventilation in neonates with respiratory distress and if lung ultrasound and aEEG criteria could be used in appreciation of the readiness for extubation of the neonatal patients resulting in a decrease of the rate of extubation failure. Material and method. There were analyzed the cases of 50 late preterm and early term neonates presenting with respiratory distress. Lung ultrasound was performed during the first 4 hours after delivery in all the neonates and then as clinically indicated in the case of ventilated patients. A lung ultrasound was performed in all the ventilated patients before extubation. 12 of the 25 ventilated patients were also monitored by aEEG. The decisions regarding the intubation and mechanical ventilation and the moment of extubation of the patients were taken by the clinicians in accordance with the local and international guidelines. The extubation failure was defined as the need to re-intubate the patient in the first 24 hours after the extubation. The lung ultrasound pattern was considered as normal if the image was consisting of A lines with rare B lines or ”double lung point” as in the case of the delayed absorption of fetal lung fluid and abnormal in the case of “white lung” appearance (coalescent B lines) or an image of consolidation. A normal aEEG was defined as the presence of a continuous normal voltage pattern with sleep-wake cycles present and an abnormal aEEG as either discontinuous normal voltage, burst-suppression, low voltage or flat background patterns. The lung ultrasound patterns in the first hours of life were compared between patients that needed intubation and those that did not need mechanical ventilation. The lung ultrasound and aEEG patterns before extubation were compared between the patients that did not need re-intubation and those with extubation failure. Results. An abnormal image on lung ultrasound was significantly associated with the risk of intubation (p &lt; 0.001) (sensitivity 84%, specificity 100%, positive predictive value 100% and negative predictive value 86.2%) An abnormal lung ultrasound pattern before extubation was associated with a significant risk of extubation failure (p &lt; 0.049) (sensitivity 75%, specificity 85%, positive predictive value 50%, negative predictive value 94.7%). In the case of the subset of patients in which aEEG was performed, an abnormal aEEG pattern was significantly associated with extubation failure (p &lt; 0.034) (sensitivity 100%, specificity 88%, positive predictive value 75%, negative predictive value 100%). In the case of association of the two parameters (lung ultrasound and aEEG pattern) there was again a statistically significant association between the abnormal patterns and extubation failure. Conclusions. An abnormal lung ultrasound during the first hours of life is a strong predictor for the need of intubation and mechanical ventilation in the neonates with respiratory distress. The normal lung ultrasound pattern just before extubation is predictive of a good evolution without the need for re-intubation of the patient. A normal aEEG pattern at the same time is associated also with a decreased risk of extubation failure.

Retrospective Analysis of EEG in Patients With COVID-19: EEG Recording in Acute and Follow-up Phases.

Background. Interest in electroencephalographic (EEG) coronavirus disease 2019 (COVID-19) findings has been growing, especially in the search for a specific-features EEG of encephalopathy. Methods. We made a retrospective analysis of 29 EEGs recorded in 15 patients with COVID-19 and neurological symptoms. We classified the EEGs as “Acute EEG” and “follow-up EEG.” We did a statistical analysis between voltage and respiratory status of the patient, stay or not in the intensive care unit (ICU), days of stay in the ICU, sedative drugs, pharmacological treatment, type of symptoms predominating, and outcome. Results. We found EEG abnormalities in all patients studied. We observed the amplitude of background <20 µV at 93% of “acute EEG,” versus only 21.4% of “follow-up EEG.” The average voltage went from 12.33 ± 5.09 µV in the acute EEGs to 32.8 ± 20.13 µV in the follow-up EEGs. A total of 60% of acute EEGs showed an intermittent focal rhythmic. We have not found a statistically significant association between voltage of acute EEG and nonneurological clinical status (including respiratory) that may interfere with the EEG findings. Conclusions. Nonspecific diffuse slowing EEG pattern in COVID-19 is the most common finding reported, but we found in addition to that, as a distinctive finding, low voltage EEG, that could explain the low prevalence of epileptic activity published in these patients. A metabolic/hypoxic mechanism seems unlikely on the basis of our EEG findings. This pattern in other etiologies is reminiscent of severe encephalopathy states associated with poor prognosis. However, an unreactive low voltage pattern in COVID-19 patients is not necessarily related to poor prognosis.

Cardiac manifestations and prognostic implications of hereditary transthyretin amyloidosis associated with transthyretin Ala97Ser

The cardiac manifestations of late-onset hereditary transthyretin amyloidosis with p.A97S variant have not been extensively studied, and the prognostic factors remain unclear. The clinical profile, echocardiography, and ECG of patients diagnosed with ATTR p.A97S polyneuropathy between 2000 and 2016 were retrospectively collected. 67 patients with ATTR p.A97S were collected. A total of 82% of patients met the criteria for left ventricular (LV) hypertrophy. Reduced global longitudinal strain (GLS) was noted in 42.1% of patients, and 14% of patients had a relative apical sparing pattern. A low voltage pattern in the ECG was observed in 31.3% of patients, while 64.2% presented with a pseudoinfarction pattern. End-systolic LV inner dimension (HR: 2.25 (95% CI: 1.01-5.01), p=0.048), reduced GLS (HR: 5.26 (1.08-25.0), p=0.039), relative apical longitudinal strain (RALS>1, HR: 8.57 (1.69-43.3), p=0.009), increased E/A ratio (HR: 6.51 (1.17-36.4), p=0.033), and increased QRS duration (HR: 1.02 (1.00-1.04), p=0.05) were correlated with reduced survival in univariate analysis. Multivariate analysis revealed reduced RALS was significantly correlated with reduced survival (HR: 13.00 (1.81-93.45), p=0.011). Our findings reveal that ATTR p.A97S is a cardiomyopathy as well as a polyneuropathic syndrome. Routine use of more contemporary echocardiographic techniques are recommended to identify cardiac amyloidosis and provide prognostic information.

Pseudo-sawtooth pattern on amplitude-integrated electroencephalography in neonatal hypoxic-ischemic encephalopathy.

The objective of this study was to describe a novel amplitude-integrated electroencephalography (aEEG) pattern in infants with hypoxic-ischemic encephalopathy (HIE) and to assess the clinical significance. The aEEG traces of infants with HIE who were treated with therapeutic hypothermia (TH) from 2012 to 2017 were analyzed. A pseudo-sawtooth (PST) pattern was defined as a periodic increase of the upper and/or lower margin of the trace on aEEG without showing seizure activities on conventional EEG (CEEG). Of the 46 infants, 6 (13%) had the PST pattern. The PST pattern appeared following a flat trace or a continuous low-voltage pattern and was followed by a burst-suppression pattern. On CEEG, the PST pattern consists of alternating cycles of low-voltage irregular activities and almost flat tracing. The PST pattern was associated with neuroimaging abnormalities and with various degrees of neurodevelopmental outcomes. Positive predictive values of the PST or worse pattern for adverse outcomes were high at 12 h after birth. A novel aEEG background pattern in infants with HIE was reported. The PST pattern likely indicates a suppressed background pattern and may be linked to unfavorable outcomes. Further multicenter validation study is needed to clarify its clinical significance.

Simplified apical four-chamber view evaluation of relative apical sparing of longitudinal strain in diagnosing AL amyloid cardiomyopathy.

To assess the diagnostic utility of a simplified approach to relative apical sparing of longitudinal strain (RAS LS) using only an apical four-chamber view (A4C) in patients with AL amyloid cardiomyopathy (ALAC). We retrospectively evaluated echocardiographic recordings of 20 patients with ALAC, 20 patients with Fabry disease-related cardiomyopathy (FD), and 20 patients with concentric hypertensive left ventricular hypertrophy (HLVH) matched for mean LV mean thickness. Peak segmental LS values of the interventricular septum and lateral LV wall were measured in the A4C using two-dimensional speckle-tracking echocardiography. RAS LS was calculated as average apical LS/(average basal LS+average midventricular LS). Relative apical sparing of longitudinal strain values in patients with ALAC (1.23±0.64) were significantly higher than those in FD patients (0.75±0.19, P<0.05) as well as in individuals with HLVH (0.75±0.23, P<0.05), but with a significant overlap. The optimal RAS LS value differentiating ALAC from FD and HLVH with 70% sensitivity and 75% specificity was 0.88 (AUC 0.79). In multivariate modeling, RAS LS was significantly additive to traditional predictors of ALAC (low QRS voltage and pseudoinfarct ECG patterns, pericardial effusion, E/e' ratio, E-wave deceleration time; P<0.05 for all models). Simplified RAS LS evaluation represents an attractive approach for diagnostics of ALAC. However, because of considerable overlap with other disorders with hypertrophic phenotype, the analysis of RAS LS in the A4C should be combined with other traditional echocardiographic and ECG predictors in differentiating ALAC from other forms of concentric LV wall thickening.

Automated EEG background analysis to identify neonates with hypoxic-ischemic encephalopathy treated with hypothermia at risk for adverse outcome: A pilot study

BackgroundTo improve the objective assessment of continuous video-EEG (cEEG) monitoring of neonatal brain function, the aim was to relate automated derived amplitude and duration parameters of the suppressed periods in the EEG background (dynamic Interburst Interval = dIBIs) after neonatal hypoxic-ischemic encephalopathy (HIE) to favourable or adverse neurodevelopmental outcome.MethodsNineteen neonates (gestational age 36–41 weeks) with HIE underwent therapeutic hypothermia and had cEEG-monitoring. EEGs were retrospectively analyzed with a previously developed algorithm to detect the dynamic Interburst Intervals. Median duration and amplitude of the dIBIs were calculated at 1 h-intervals. Sensitivity and specificity of automated EEG background grading for favorable and adverse outcomes were assessed at 6 h-intervals.ResultsDynamic IBI values reached the best prognostic value between 18 and 24 h (AUC of 0.93). EEGs with dIBI amplitude ≥15 μV and duration <10 s had a specificity of 100% at 6–12 h for favorable outcome but decreased subsequently to 67% at 25–42 h. Suppressed EEGs with dIBI amplitude <15 μV and duration >10 s were specific for adverse outcome (89–100%) at 18–24 h (n = 10). Extremely low voltage and invariant EEG patterns were indicative of adverse outcome at all time points.ConclusionsAutomated analysis of the suppressed periods in EEG of neonates with HIE undergoing TH provides objective and early prognostic information. This objective tool can be used in a multimodal strategy for outcome assessment. Implementation of this method can facilitate clinical practice, improve risk stratification and aid therapeutic decision-making. A multicenter trial with a quantifiable outcome measure is warranted to confirm the predictive value of this method in a more heterogeneous dataset.

Usefulness of early electroencephalography (EEG) in acute central nervous system (CNS) complications of children treated for oncohematological disorders

Objective: To investigate the impact of early EEG in the diagnosis, management and prognosis of acute CNS complications in children treated for oncohematological disorders. Methods: We considered patients treated (chemotherapy and/or bone marrow transplantation) in our Department from 2007 to 2014. Inclusion criteria were: age <18 years; acute CNS complication defined as focal neurological signs and/or motor seizures and/or altered mental status; video-EEG recorded within 48 hours from onset. We retrospectively and blindly reviewed the EEGs to evaluate pattern and location of EEG abnormalities as well as their impact in diagnosis, management and prognosis. Results: Forty-one out of 443 patients presented acute CNS complications (9,3%). Thirty-six patients (24 transplanted) met the inclusion criteria. 32/36 EEGs showed abnormalities. Ictal EEG activity was observed in 5 patients (3 nonconvulsive status epilepticus, 1 nonconvulsive focal seizure and 1 burst suppression); all the nonconvulsive seizures were associated with Posterior Reversible Encephalopathy Syndrome (PRES) and required intravenous antiepileptic therapy. Twenty-seven EEGs displayed non ictal patterns: slowing in 24 (66,7%), periodic lateralized epileptiform discharges (PLEDs) in 7 (19,4%), low voltage in 5 (13,9%). Slowing was observed in children with PRES, infectious encephalitis and disease progression, PLEDs were detected only in children with PRES while low voltage pattern was found mainly in cerebral haemorrhages (3/5 patients). Mortality rate was 27,8% and low voltage pattern was associated with negative outcome. Conclusion: Our results show that EEG is a helpful tool in the diagnosis and management of CNS complications in children treated for oncohematological disorders: in particular EEG allowed us to promptly diagnose and treat nonconvulsive seizures, otherwise missed. Based on our experience, we suggest that EEG should be considered early in the diagnostic work-up of these children.

Early amplitude-integrated electroencephalography for monitoring neonates at high risk for brain injury

ObjectiveThis study aimed to correlate amplitude-integrated electroencephalography findings with early outcomes, measured by mortality and neuroimaging findings, in a prospective cohort of infants at high risk for brain injury in this center in Brazil. MethodsThis blinded prospective cohort study evaluated 23 preterm infants below 31 weeks of gestational age and 17 infants diagnosed with hypoxic-ischemic encephalopathy secondary to perinatal asphyxia, with gestational age greater than 36 weeks, monitored with amplitude-integrated electroencephalography in a public tertiary center from February 2014 to January 2015. Background activity (classified as continuous, discontinuous high-voltage, discontinuous low-voltage, burst-suppression, continuous low-voltage, or flat trace), presence of sleep-wake cycling, and presence of seizures were evaluated. Cranial ultrasonography in preterm infants and cranial magnetic resonance imaging in infants with hypoxic-ischemic encephalopathy were performed. ResultsIn the preterm group, pathological trace or discontinuous low-voltage pattern (p=0.03) and absence of sleep-wake cycling (p=0.019) were associated with mortality and brain injury assessed by cranial ultrasonography. In patients with hypoxic-ischemic encephalopathy, seizure patterns on amplitude-integrated electroencephalography traces were associated with mortality or brain lesion in cranial magnetic resonance imaging (p=0.005). ConclusionThis study supports previous results and demonstrates the utility of amplitude-integrated electroencephalography for monitoring brain function and predicting early outcome in the studied groups of infants at high risk for brain injury.

Abstract 11686: Pericellular Amyloid Infiltration in Biopsy-proven Cardiac Amyloidosis

Background: Cardiac amyloidosis is a rare disease characterized by the myocardial infiltration of amyloid. There are several histopathological patterns of amyloid accumulation, of which pericellular amyloid pattern is classified when amyloid is observed around each cardiomyocyte in endomyocardial biopsy. However, the relationship between pericellular amyloid deposition pattern and clinical characteristics has not yet been investigated. Objective: We retrospectively investigated endomyocardial biopsy-proven cardiac amyloidosis with pericellular amyloid deposition. Methods: Thirty cardiac amyloidosis patients in our institution were included. Results: Thirteen patients (43%) were pathologically classified into pericellular amyloid deposition. In the baseline characteristics, the patients with pericellular deposition had significantly lower age (69 ± 9 vs. 75 ± 6 years, p = 0.032) and higher brain natriuretic peptide levels (681 ± 516 vs. 267 ± 393 pg/ml, p = 0.003), compared with those without pericellular deposition. Electrocardiographic findings revealed that patients with pericellular amyloid deposition had significantly higher incidence of low voltage (46 vs. 12%, p = 0.045) and pseudoinfarction pattern (46 vs. 6%, p = 0.015), compared with patients without pericellular deposition. Echocardiography revealed that patients with pericellular deposition had significantly decreased deceleration time (152 ± 49 vs. 191 ± 50 ms, p = 0.049). Hemodynamic findings did not show significant difference between groups. High-sensitivity cardiac troponin-T levels were also analyzed in 14 cardiac amyloidosis patients without ischemic heart disease. Patients with pericellular amyloid deposition had significantly higher high-sensitivity cardiac troponin-T levels, compared with patients without pericellular deposition (0.128 ± 0.07 vs. 0.046 ± 0.03 pg/ml, p = 0.016). Conclusion: Pericellular amyloid deposition pattern was associated with electrocardiographic abnormalities, diastolic dysfunction, and ongoing myocardial damage. Our data suggest direct amyloid infiltration around the cardiomyocytes may cause myocardial damage, providing possible pathophysiological implication of the failing heart in cardiac amyloidosis.

Low-voltage pattern and absence of sleep-wake cycles are associated with severe hemorrhage and death in very preterm infants.

Amplitude integrated electroencephalogaphy (aEEG) is becoming an important tool for the assessment of cerebral activity in preterm newborns. Describing the relationship between early aEEG patterns and intraventricular hemorrhage (IVH) can improve our knowledge of neurological injury in the preterm newborn. The aim of this prospective study was to identify early changes in the aEEG in premature newborns that could be associated to severe neurological lesion/death. Preterm newborns with a birth weight ≤1,500 g and/or 32 weeks of gestation were included. aEEG monitoring was performed during the first 72 h of life. A qualitative analysis of the aEEG recordings was performed, based on continuity, sleep-wake cycles (SWCs), inferior lower margin amplitude (LMA), and bandwidth (BW). Key outcomes were severe IVH and/or death. Ninety-two subjects were included (mean gestational age 28 weeks). In 28.6 % of subjects with HIV III/IHP, a low-voltage pattern was observed. A statistically significant relationship was found between low-voltage tracings and death and neurological lesion/death. Absent SWCs during the first 72 h were also related to death. Early aEEG patterns can be predictive of neurological outcome in the preterm newborn. Low-voltage tracing and absence of SWCs are associated with severe neurological lesions/death.

Skeletal scintigraphy indicates disease severity of cardiac involvement in patients with senile systemic amyloidosis

BackgroundSenile systemic amyloidosis (SSA) is a common aging phenomenon in the elderly population. Nevertheless, pre-mortem diagnosis of SSA is rare. Thus, data on clinical characterization and disease severity are limited. Methods36 consecutive SSA patients (71.6 [64.7–82.7]years) were evaluated by electrocardiography, echocardiography, laboratory tests, and 99mTechnetium-3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) scintigraphy (n=20). ResultsIn addition to cardiac involvement, amyloid deposition was found in rectum (n=6), peripheral nerves (n=2), and urinary bladder (n=2). Five patients showed low voltage pattern. Thickness of interventricular septum (IVS) was 20 [12–27]mm. LV longitudinal function was diminished (TDI-s 5 [3–11] cm/s; MAPSE 6.5 [2.5–19]mm; TAPSE 12.5 [2–24]mm). LV systolic function (LV-EF<45%) was markedly decreased in 19 patients. Plasma levels of troponin T (0.05 [0.01–0.23]µg/L) and NT-proBNP (4318 [205–16597]ng/L) were elevated. 99mTc-DPD heart retention was 7.8 [2.4–11.0]% and correlated with MAPSE (ρ=−0.716; p=0.0018), TAPSE (ρ=−0.491; p<0.05), and IVS (ρ=0.556; p=0.0153). Heart-to-body ratio correlated with MAPSE (ρ=−0.771; p=0.0018), IVS (ρ=0.603; p=0.0086).Twelve patients died during follow-up of 27.4 [0.1–106.2]months. Exclusively 99mTc-DPD heart retention, diastolic dysfunction and in trend MAPSE were associated with patient's outcome. Interestingly, risk predictors that were well established in patients with AL amyloidosis were not predictive for survival in patients with SSA. ConclusionsThis study gave first evidence that 99mTc-DPD HR may be capable to display the extent of cardiac amyloid deposition. Moreover, this study suggested that 99mTc-DPD HR, diastolic dysfunction and in trend MAPSE are associated with poor outcome. Nevertheless, these findings need to be established in a larger prospective trial.

Video-EEG monitoring in newborns with hypoxic-ischemic encephalopathy treated with hypothermia

Therapeutic hypothermia (TH) is becoming standard of care in newborns with hypoxic-ischemic encephalopathy (HIE). The prognostic value of the EEG and the incidence of seizures during TH are uncertain. To describe evolution of EEG background and incidence of seizures during TH, and to identify EEG patterns predictive for MRI brain injury. A total of 41 newborns with HIE underwent TH. Continuous video-EEG was performed during hypothermia and rewarming. EEG background and seizures were reported in a standardized manner. Newborns underwent MRI after rewarming. Sensitivity and specificity of EEG background for moderate to severe MRI brain injury was assessed at 6-hour intervals during TH and rewarming. EEG background improved in 49%, remained the same in 38%, and worsened in 13%. A normal EEG had a specificity of 100% upon initiation of monitoring and 93% at later time points. Burst suppression and extremely low voltage patterns held the greatest prognostic value only after 24 hours of monitoring, with a specificity of 81% at the beginning of cooling and 100% at later time points. A discontinuous pattern was not associated with adverse outcome in most patients (73%). Electrographic seizures occurred in 34% (14/41), and 10% (4/41) developed status epilepticus. Seizures had a clinical correlate in 57% (8/14) and were subclinical in 43% (6/14). Continuous video-EEG monitoring in newborns with HIE undergoing TH provides prognostic information about early MRI outcome and accurately identifies electrographic seizures, nearly half of which are subclinical.

554 Correlation Between Amplitude- Integrated Eeg (AEEG) and General Movements (GMS) in Preterm Infants

Since today the correlation between background cerebral electrical activity at aEEG and brain injury in preterm is unknown. The aim of the present study is to correlate the background activity at aEEG to the patterns of General Movements at writhing age and to avaluate if aEEG is predictive for cerebral palsy. Methods: 17 preterms between 27 and 31 weeks of gestational age with normal head ultrasound were included. The aEEG were recorded during the first 24 hours of life for 60 minutes. The averaged signals were analysed off-line. Background activity was classified into three patterns categories: discontinous low-voltage pattern (minimal amplitude < 3µV), discontinous high voltage pattern (minimal amplitude between 3 and 5 µV) and continous pattern. General movements were performed during the first 24 hours of life and weekly during writhing age. Results: A background low-voltage pattern correlates positively with Cramped Synchronized General Movements (R: 0.74, p = 0.004), on the other way a high voltage pattern and a continous pattern correlates with normal General Movements (R: 0.67, p=0.006). Conclusions: A discontinous low voltage pattern at aEEG in preterm could be expression of cerebral injury and/or altered maturation. In fact this aEEG pattern highly correlates with pathological Cramped Synchronized General Movements leading to the hypotesis of a similar strong correlation between discontinous low voltage pattern and cerebral palsy in this range of gestational age.

Design and Analysis of CMOS-Controlled Tunable Photodetectors for Multiwavelength Discrimination

In this paper, a metal-semiconductor-metal (MSM) based photodetector for multiple wavelength discrimination is fully introduced and analyzed. Its spectral response is programmable electrically through a set of low-voltage binary patterns that can be generated from CMOS circuits. Consequently, the wavelength reconfiguration time of the detector is set primarily by the electronics switching time, which is on the order of nanoseconds. Additionally, the spectral response of the detector can be arbitrarily shaped for any specific system need based on algorithms we introduce here. The nanosecond wavelength reconfigurability feature of the detector offers flexibility for designing high-efficiency wavelength reconfigurable optical networks.