In Graves' disease, thyroid autoantibodies and ultrasound features correlate with distinctive histological features

PURPOSE

Laboratory, imaging, and pathological features of Graves' disease (GD), although well characterized, have been barely correlated each other. Aim of the study was to link laboratory and ultrasound characteristics of GD with its pathological features.

METHODS

We correlated laboratory and ultrasound data at the time of diagnosis in 28 consecutive GD patients who underwent thyroidectomy with their pathological features, i.e., lymphocytic infiltration and follicular hyperplasia (both classified as mild or severe).

RESULTS

Thyroid volume correlated positively with the levels of FT4 (P = 0.002, r² = 0.42), FT3 (P = 0.011, r² = 0.22), autoantibodies to thyroglobulin (TgAbs) (P = 0.016, r² = 0.32), autoantibodies to thyroid peroxidase (TPOAbs) (P = 0.011, r² = 0.34) and the extent of lymphocytic infiltration (P = 0.006 comparing mild to severe lymphocytic infiltration) but not with the levels of autoantibodies to the thyrotropin receptor (TRAbs) and to follicular hyperplasia. Compared to subjects with mild lymphocytic infiltration, those with severe lymphocytic infiltration showed higher levels of TgAbs (316 vs 0.0 IU/mL, P < 0.0001) and TPOAbs (295 IU/mL vs 14 IU/mL, P < 0.0001) and similar levels of TRAbs (7.5 vs 13 IU/mL, P = 0.68). Compared to patients with mild, those with severe follicular hyperplasia had similar levels of TgAbs (76 vs 30 IU/mL, P = 0.31) and TPOAbs (251 IU/mL vs 45 IU/mL, P = 0.26) but higher levels of TRAbs (39 vs 7.2 IU/mL, P < 0.001).

CONCLUSION

In GD, TgAbs and TPOAbs levels correlate with the extent of lymphocytic infiltration, TRAbs levels with the degree of follicular hyperplasia. Thyroid volume, the main factor influencing the severity of hyperthyroidism, is related to lymphocytic infiltration and not to follicular hyperplasia.

Observation of Rayleigh-Lamb waves generated by the 2022 Hunga-Tonga volcanic eruption with the POLA detectors at Ny-Ålesund

The eruption of the Hunga-Tonga volcano in the South Pacific Ocean on January 15, 2022, at about 4:15 UTC, generated a violent explosion, which created atmospheric pressure disturbances in the form of Rayleigh-Lamb waves detected all over the globe. Here we discuss the observation of the Hunga-Tonga shock-wave performed at the Ny-Ålesund Research Station on the Spitsbergen island, by the detectors of the PolarquEEEst experiment and their ancillary sensors. Online pressure data as well as the results of dedicated offline analysis are presented and discussed in details. Results include wave arrival times, wave amplitude measurements and wave velocity calculation. We observed five passages of the shock wave with a significance larger than 3 [Formula: see text] and an amplitude up to 1 hPa. The average propagation velocity resulted to be (308 ± 0.6) m/s. Possible effects of the atmospheric pressure variation associated with the shock-wave multiple passages on the cosmic-ray rate at ground level are also investigated. We did not find any significant evidence of this effect.

A multicentric observational study of patients affected by advanced heart failure with implantable cardioverter defibrillator and left ventricular assist devices

Funding Acknowledgements

Type of funding sources: None.

Background

Left ventricular assist device (LVAD) implantation is increasingly used in patients with end-stage heart failure. Most patients already have an implantable defibrillator (ICD) at the time of L-VAD implantation. Studies on this patient population are limited by the small sample size and the short duration of follow-up.

Purpose

The aim of this study was to retrospectively describe the real-world management of patients implanted with both ICD and LVAD. The main objective was to evaluate the incidence and predictors of appropriate and inappropriate therapies of the ICD and the incidence and predictors of ICD related complications.

Methods

212 patients were enrolled in four Centers in the period between July 2006 and November 2020. The inclusion criteria were age&gt; 18 years, advanced heart failure, patients with ICD and concomitant or subsequent continuous flow LVAD implantation. ICD therapy was defined as antitachycardia pacing therapy or shock.

The data available at the last visit with a median follow up of 21 months were analyzed.

Outcome predictors were assessed by univariate logistic regression and the variables of interest included in a multivariate model.

Results

The rate of appropriate ICD therapies was 29.7%, while the incidence of inappropriate therapies was 10.4%; in the multivariate analysis the presence of a zone therapy with low detection rate (VT zone with median detection rate of 164.5 bpm) was found to be an independent predictor of the composite of appropriate and inappropriate therapies (OR = 19.05; CI = 2.19-165.21; p = 0.007). Interference between ICD and LVAD occurred in 7.5% of cases; the incidence of infectious complications related to the ICD was 7.1% and bleeding complications of 5.2%; in the multivariate analysis, ICD generator replacement was an independent predictor of total complications related to the ICD (interference, infectious and bleeding; OR = 4.45; IC = 1.60-12.36; p = 0.004). 103 patients had CRT defibrillator (48,6%). At follow up there was no statistically significant difference in the incidence of appropriate therapies between those who had CRT-on (n=74) and those who had CRT-off (n=29; p = 0.61).

Conclusions

Patients with LVAD implanted with an ICD experience a high rate of appropriate and inappropriate ICD therapies. An active VT zone at low heart rate was found to be an independent predictor of ICD therapies. Of more, ICD generator replacement was found to be an independent predictor of total complications related to the ICD. Our findings suggest the importance of tailoring device programming in order to minimize the incidence of ICD therapies, thus sparing the need for generator replacement in this population.

Temporal trend of QRS voltage amplitude on surface sensing in patients with arrhythmogenic cardiomyopathy implanted with a subcutaneous ICD

Funding Acknowledgements

Type of funding sources: None.

Introduction

Previous studies have reported a significant decrease in ventricular sensing amplitude during follow-up in patients with arrhythmogenic cardiomyopathy (ACM) implanted with trans-venous implantable cardioverter defibrillator (ICD). No data are yet available on sensing amplitudes values over time for subcutaneous ICD (S-ICD). Low QRS voltage on surface ECG is one of the diagnostic clues in ACM. This, together with the progressive nature of the disease and the not-negligible incidence of inappropriate shocks due to oversensing, raise safety concerns on the use of S-ICD in this population.

Aim

The aim of this study was to evaluate the trend of QRS amplitude on subcutaneous ECG (S-ECG) over time in patients with ACM implanted with S-ICD.

Methods

We conducted a retrospective analysis on a cohort of consecutive patients with ACM implanted with S-ICD in two tertiary centers, prospectively enrolled in the home-monitoring program. The S-ECGs recorded by the S-ICD at the time of first and last data transmission were analyzed. The voltage amplitude was estimated for each QRS complex available, and the values obtained were compared between the two time points (i.e. baseline and last follow-up available). The primary endpoint of our study was the proportion of patients in which the decrease of QRS amplitude during follow-up was statistically significant.

Results

Eleven patients (1 female, 9%) were enrolled in this study. The mean age was 43±10 years. An exclusive right ventricular involvement was reported in 5 patients (46%), 2 patients (18%) had an exclusive left ventricular, and 4 (36%) a biventricular involvement. Three patients (27%) were implanted in secondary prevention. During a median follow-up of 9 months (IQR 6-17), 6 patients (55%, 95%CI 24-84%) experienced a statistically significant reduction in the S-ECG QRS amplitude (Figure A). Considering these 6 patients, the mean absolute reduction was -0.46±0.32 mV corresponding to a relative reduction of -19%±11%. Moreover, we found a statistically significant correlation between follow-up duration and QRS amplitude relative reduction (r=-0.89, p=0.018, Figure B). No patients experienced inappropriate shocks.

Conclusions

In a cohort of ACM patients implanted with S-ICD the majority of patients experienced a significant reduction in the amplitude of QRS voltage during follow-up, confirming a potential safety concern on the use of S-ICD in this population. Further studies are needed to investigate this issue.

Feasibility of an automatic ultrasonographic image acquisition system associated with an artificial intelligence algorithm for real-time monitoring of cardiac motion during cardiac radio-ablation

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): This publication is part of a project that has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 954783.

Background

Stereotactic arrhythmia radio-ablation (STAR) is a promising strategy for the non-invasive treatment of ventricular arrhythmias (VA). The management of the cardio-respiratory motion of the target and the reduction of the uncertainties related to patients’ positioning are two of the main challenges that STAR has to overcome. A prototype of a system was developed that can automatically acquire and interpret echocardiographic images using an artificial intelligence (AI) algorithm to calculate cardiac displacement in real-time.

Purpose

To evaluate the feasibility of this automatic acquisition system in patients with a history of VA.

Methods

We conducted a single center, feasibility study enrolling consecutive patients with a history of VA. Echocardiographic images were automatically acquired from the parasternal and apical views with a dedicated probe. The system was designed to hold the probe fixed to the chest in the supine position during both free-breathing and short expiratory breath-hold sequences, to simulate STAR treatment. The primary endpoint was the percentage of patients reaching a score ≥2 in a multi-parametric assessment evaluating the quality of automatically acquired images in terms of: A - allowing a proper identification of the cardiac cycle phase using the AI algorithm, B - allowing a correct measurement of the heart displacement by the AI algorithm, C - ability to visually distinguish typical cardiac structures, and D - stability of the image throughout the respiration cycle. Moreover, we investigated the potential impact of clinical and demographic characteristics on achieving the primary outcome.

Results

From May to September 2021, we enrolled 24 patients (63±14 years, 21% females). All of them had a history of VA and 21 (88%) had an ICD. Eight patients (33%) had coronary artery disease, 12 (50%) had non-ischemic cardiomyopathy, and 3 had idiopathic VA. Parasternal as well as apical images were obtained from all patients except from one, in whom parasternal view could not be collected due to the patient’s inability to maintain the supine position. The primary outcome was achieved in 23 patients (96%) for the apical view, in 20 patients (87%) for the parasternal view, and in all patients in at least one of the two views. The images quality was maximal (i.e. score=4) in at least one of the two windows in 19 patients (79%). Atrial fibrillation arrhythmia was the only clinical characteristics associated with a poor score outcome in both imaging windows (apical p=0,022, parasternal p=0,014).

Conclusion

An automatic ultrasonographic image acquisition system associated with an AI algorithm is feasible for real-time monitoring of cardiac motion in patients with a history of VA. The possibility of real-time, non-invasive monitoring of cardiac position would lead to a significant improvement in the quality and safety of STAR treatment, particularly in case of treatment with heavy particles such as protons and carbon ions.

P27 MONOMORPHIC VENTRICULAR TACHYCARDIA INDUCED BY BLUNT CHEST TRAUMA IN A YOUNG MAN WITHOUT STRUCTURAL HEART DISEASE: A CASE REPORT

Introduction

Life–threatening ventricular arrhythmias secondary to chest trauma without structural cardiac damage (i.e. commotio cordis [CC]) are a rare but dramatic cause of sudden cardiac death. We present a case of fast ventricular tachycardia (VT) induced by blunt chest trauma in a healthy man during sports activity.

Case Presentation

A 22–year–old man, competitive soccer player, was admitted to our hospital for VT. A few hours before admission, after a heavy ball impact in the chest during a soccer match, he suddenly reported fast and regular palpitation with lightheadedness and dyspnea, without loss of consciousness. The emergency medical service was activated, and the evaluation revealed a hemodynamically tolerated monomorphic VT with a rate of almost 285 bpm (Fig.A). Amiodaron infusion was ineffective and sinus rhythm (SR) was restored by electrical cardioversion. At the time of admission, he was asymptomatic. Familiar history, past medical history and physical examination were unremarkable. ECG revealed regular SR, with minimal right bundle branch conduction delay (Fig.B). Blood samples showed normal blood cells count, electrolyte concentrations and liver, kidney, and thyroid function; seriate high sensitivity troponin I determinations were negative. Echocardiography and cardiac magnetic resonance showed normal findings. Computed tomography angiography excluded coronary anomalies. Exercise test revealed no signs of cardiac ischemia and no effort–induced arrhythmias. The fluoroscopy–free unipolar and bipolar voltage maps showed normal electrograms throughout the right ventricle (Fig.C). No sustained arrhythmias were induced by programmed ventricular stimulation. The patient was then discharged with the indication to cardiology follow–up and the advice to avoid contact sports activities.

Discussion

VT is a rare presentation of CC. It has been proposed that CC occurs when a chest strike timed at the upstroke of the T–wave causes both ventricular depolarization trigger and altered dispersion of repolarization, mainly via activation of KATP channels. In the absence of structural heart disease (SHD), the usual presenting rhythm is ventricular fibrillation and there are no accepted mechanisms to explain monomorphic VT in this context. Some authors reported monomorphic VT after chest trauma as the first manifestation of arrhythmogenic cardiomyopathy. Therefore, a careful follow–up will be needed to exclude future development of SHD in this patient.

P31 PERCUTANEOUS LEFT STELLATE GANGLION BLOCK AS PRE–TREATMENT STRATEGY FOR HIGH–RISK PATIENTS WHO ARE CANDIDATES FOR INVASIVE PROCEDURES POTENTIALLY ASSOCIATED WITH ADRENERGIC STIMULATION: AN HYPOTHESIS–GENERATING CASE REPORT

Introduction

Percutaneous left stellate ganglion block (PLSGB) has been reported as a safety and effective procedure for the management of refractory arrhythmic storm (AS). In this report we present a case of a man with refractory AS effectively treated with PLSGB, subsequently candidate for an invasive procedure potentially associated with adrenergic stimulation and propose the use of this technique as pre–treatment strategy in this clinical setting.

Case presentation

A 57–year–old man was admitted to our hospital for AS. Past medical history revealed that two years earlier he had been treated with primary percutaneous coronary intervention for ST–segment elevation myocardial infarction. Four months before admission he underwent coronary artery bypass graft surgery with concomitant mechanical mitral valve replacement, closure of an interventricular defect and, considering the severe left ventricular disfunction, he was implanted with an automatic defibrillator in primary prevention. At the time of admission, he was treated with lidocaine infusion with remission of arrhythmic events. Comprehensive diagnostic workup revealed no overt triggers for AS. Five days after admission, the patient experienced recurrence of ventricular arrhythmias (VA), refractory to amiodarone, lidocaine, and magnesium infusion, increased pacing rate, and sedation with dexmedetomidine. PLSGB was then attempted with the injection of lidocaine and ropivacaine using an anatomical approach with complete remission of arrhythmic events. After a week free from VAs, a new AS was observed and PLSGB was repeated using the same modality with complete arrhythmic resolution. Considering the advanced heart failure, the patient was candidate to heart transplantation (HT) and, before undergoing gastro– and colonoscopy required for inclusion in the HT program, with the aim to reduce the risk of VA recurrences triggered by potential adrenergic stimulation, we pre–treated the patient with PLSGB using only ropivacaine, with successful induction of temporary Horner syndrome (Fig. A). The endoscopy procedures were performed successfully with no VA events and the patient was then discharged waiting for HT.

Conclusion

We propose the use of PLSGB as a pre–treatment strategy for patients at high–risk of VAs who are candidates for invasive procedures potentially associated with adrenergic stimulation. This report could be hypotheses–generating for further studies on this topic.

P9 TEMPORAL TREND OF QRS VOLTAGE AMPLITUDE ON SURFACE SENSING IN PATIENTS WITH ARRHYTHMOGENIC CARDIOMYOPATHY IMPLANTED WITH A SUBCUTANEOUS ICD

Introduction

Previous studies have reported a significant decrease in ventricular sensing amplitude during follow–up in patients with arrhythmogenic cardiomyopathy (ACM) implanted with trans–venous implantable cardioverter defibrillator (ICD). No data are yet available on sensing amplitude values over time for subcutaneous ICD (S–ICD). Low QRS voltage on surface ECG is one of the diagnostic clues in ACM. This, together with the progressive nature of the disease and the not–negligible incidence of inappropriate shocks due to oversensing, raise safety concerns on the use of S–ICD in this population. The aim of this study was to evaluate the trend of QRS amplitude on subcutaneous ECG (S–ECG) over time in patients with ACM implanted with S–ICD.

Methods

We conducted a retrospective analysis on a cohort of consecutive patients with ACM implanted with S–ICD in two Italian tertiary centers, prospectively enrolled in the home–monitoring program. The S–ECGs recorded at the time of first and last data transmission were analyzed. The voltage amplitude was estimated for each QRS complex available, and the values obtained were compared between the two time points (i.e. baseline and last follow–up available). The primary endpoint of our study was the proportion of patients in which the decrease of QRS amplitude during follow–up was statistically significant.

Results

Eleven patients (1 female, 9%) were enrolled in this study. The mean age was 43±10 years. An exclusive right ventricular involvement was reported in 5 patients (46%), 2 patients (18%) had an exclusive left ventricular, and 4 (36%) a biventricular involvement. Three patients (27%) were implanted in secondary prevention. During a median follow–up of 9 months (IQR 6–17), 6 patients (55%, 95%CI 24–84%) experienced a statistically significant reduction in the S–ECG QRS amplitude (Fig. A). Considering these 6 patients, the mean absolute reduction was –0.46±0.32 mV corresponding to a relative reduction of –19%±11%. Moreover, we found a statistically significant correlation between follow–up duration and QRS amplitude relative reduction (r=–0.89, p = 0.018, Fig. B). No patients experienced inappropriate shocks.

Conclusions

In a cohort of ACM patients implanted with S–ICD the majority of patients experienced a significant reduction in the amplitude of QRS voltage during follow–up, confirming a potential safety concern on the use of S–ICD in this population. Further studies are needed to investigate this issue.

Prognostic impact of achieving LDL cholesterol guidelines-recommended target in secondary prevention: a real-world study

Background

Lipid management plays a key role in secondary prevention after acute coronary syndrome. The 2019 European Society of Cardiology guidelines recommend a more ambitious target than the previous guidelines version (i.e., to achieve LDL cholesterol [LDL-C] &lt;55 mg/dL, and to reduce it ≥50% form baseline vs LDL-C&lt;70 mg/dl or reduced ≥50% form baseline). Currently, data on the reduction of cardiovascular events in patients achieving the 2019 goals in a real-world population are missing.

Purpose

The aim of this study was to determine the risk of major adverse cardiovascular events (MACE) during follow-up in post myocardial infarction (PMI) patients according to the achievement of the guidelines-recommended goals in terms of LDL-C reduction.

Methods

We conducted a retrospective analysis of a monocentric observational registry prospectively enrolling patients admitted to our hospital for ST segment elevation myocardial infarction and followed-up in our dedicated PMI ambulatory. The analysis considered the patients enrolled between January 2011 and February 2019. Demographical and clinical data were extracted from a dedicated digital database, and the clinical events occurred during follow-up were obtained by telephone interviews or clinical records. We considered a combined endpoint of MACE defined as all-cause death, non-fatal MI, non-fatal stroke and unplanned revascularization. LDL-C was collected at baseline and at 1, 6 and 12 months after the event. The lower value collected at follow-up was used to define the achievement of the target goals. We conducted a Kaplan-Meier analysis and log-rank test comparing patients who achieved LDL-C &lt;55 mg/dL and ≤50% from baseline (group 2019) vs those with LDL-C &lt;70 mg/dL or ≤50% from baseline (group 2016). Continue variable are presented as median (interquartile range).

Results

A total of 1201 patients (23% female) were included in our analysis. Median age was 63 (54–72) years, 56% had hypertension, 17% diabetes, and 38% were smoker. Baseline LDL-C was 123 (97–148) mg/dL, the median LDL-C at follow-up was 63 (52–78) mg/dL, significantly reduced from baseline (P&lt;0.0001). Between 6 and 12 months 83% of patients were treated with statin therapy alone (73% high intensity), and 17% with the addition of ezetimibe. The 2016 target was achieved in 828 patients (69%), while 270 patients (22.5%) obtained also the 2019 target. Median follow-up was 60 (40–77) months. The net incidence of MACE was 12.9% in group 2019 vs 23.7% in group 2016 (HR 0.61; 95% CI 0.42–0.88; P log-rank=0.0087; Number Needed to Treat=9; see Figure).

Conclusion

Our data from a real-world cohort of PMI patients emphasize the importance of achieving the guideline-recommended secondary prevention goals of LDL-C&lt;55 mg/dl and ≤50% from baseline in order to reduce MACE.

Funding Acknowledgement

Type of funding sources: None.

Is colchicine safe for cardiovascular indications?

Background

Colchicine has an emerging role in the cardiovascular field (e.g. acute and chronic coronary syndromes, pericarditis, atrial fibrillation), although, concerns for side effects, especially gastrointestinal, may limit its prescription.

Aims

We aimed at evaluating reported side effects of colchicine for cardiovascular indications.

Methods

We performed a meta-analysis of published randomized controlled trials on colchicine for the treatment of cardiovascular diseases. Random-effects meta-analysis was used to assess the risk of adverse events and drug withdrawal. Publication bias was assessed using the Egger test, and meta-regression was performed to assess sources of heterogeneity.

Results

Among 14 188 patients, 7136 patients received colchicine while the other 7052 received placebo. The occurrence of any adverse event with colchicine was reported in 15.3 vs. 13.9% patients [relative risk (RR) 1.26, 95% confidence interval (CI) 0.96–1.64, P=0.09, see figure]. Gastrointestinal events were reported in 16.1 vs. 12.2% (RR 2.16, 95% CI 1.50–3.12, P&lt;0.001), while diarrhoea was reported in 12.5 vs. 8.1% (RR 2.77, 95% CI 1.55–4.94, P&lt;0.001). The risk of gastrointestinal events increased with daily dose and shorter treatment duration. Myalgias were observed in 21 vs. 18% patients (RR 1.16, 95% CI 1.02–1.32, P=0.03). Other adverse events such as myotoxicity, hepatic adverse events, hematologic adverse events, cutaneous adverse events, infection or death were not increased by colchicine treatment. Colchicine discontinuation was reported in 4.8 vs. 3.4% patients (RR 1.54, 95% CI 1.20–1.99, P&lt;0.001).

Conclusions

Colchicine is associated with increased risk of gastrointestinal events and myalgias, but not of other adverse events. The risk of gastrointestinal events may be avoided with lower dose (0.5 mg/daily) and is inversely related to treatment duration, possibly due to early drug discontinuation or drug tolerance.

Funding Acknowledgement

Type of funding sources: None.

Reported muscle symptoms during statin treatment amongst Italian dyslipidaemic patients in the real-life setting: the PROSISA Study

AIM

Statin-associated muscle symptoms (SAMS) are a major determinant of poor treatment adherence and/or discontinuation, but a definitive diagnosis of SAMS is challenging. The PROSISA study was an observational retrospective study aimed to assess the prevalence of reported SAMS in a cohort of dyslipidaemic patients.

METHODS

Demographic/anamnestic data, biochemical values and occurrence of SAMS were collected by 23 Italian Lipid Clinics. Adjusted logistic regression was performed to estimate odds ratio (OR) and 95% confidence intervals for association between probability of reporting SAMS and several factors.

RESULTS

Analyses were carried out on 16 717 statin-treated patients (mean ± SD, age 60.5 ± 12.0 years; 52.1% men). During statin therapy, 9.6% (N = 1599) of patients reported SAMS. Women and physically active subjects were more likely to report SAMS (OR 1.23 [1.10-1.37] and OR 1.35 [1.14-1.60], respectively), whist age ≥ 65 (OR 0.79 [0.70-0.89]), presence of type 2 diabetes mellitus (OR 0.62 [0.51-0.74]), use of concomitant nonstatin lipid-lowering drugs (OR 0.87 [0.76-0.99]), use of high-intensity statins (OR 0.79 [0.69-0.90]) and use of potential interacting drugs (OR 0.63 [0.48-0.84]) were associated with lower probability of reporting SAMS. Amongst patients reporting SAMS, 82.2% underwent dechallenge (treatment interruption) and/or rechallenge (change or restart of statin therapy), with reappearance of muscular symptoms in 38.4% (3.01% of the whole cohort).

CONCLUSIONS

The reported prevalence of SAMS was 9.6% of the whole PROSISA cohort, but only a third of patients still reported SAMS after dechallenge/rechallenge. These results emphasize the need for a better management of SAMS to implement a more accurate diagnosis and treatment re-evaluation.

Probing anharmonic phonons by quantum correlators: A path integral approach

We devise an efficient scheme to determine vibrational properties from Path Integral Molecular Dynamics (PIMD) simulations. The method is based on zero-time Kubo-transformed correlation functions and captures the anharmonicity of the potential due to both temperature and quantum effects. Using analytical derivations and numerical calculations on toy-model potentials, we show that two different estimators built upon PIMD correlation functions fully characterize the phonon spectra and the anharmonicity strength. The first estimator is associated with the force-force quantum correlators and, in the weak anharmonic regime, yields reliable zero-point motion frequencies and thermodynamic properties of the quantum system. The second one is instead connected to displacement-displacement correlators and accurately probes the lowest-energy phonon excitations, regardless of the anharmonicity strength of the system. We also prove that the use of generalized eigenvalue equations, in place of the standard normal mode equations, leads to a significant speed-up in the PIMD phonon calculations, both in terms of faster convergence rate and smaller time step bias. Within this framework, using ab initio PIMD simulations, we compute phonon dispersions of diamond and of the high-pressure I4₁/amd phase of atomic hydrogen. We find that in the latter case, the anharmonicity is stronger than previously estimated and yields a sizeable red-shift in the vibrational spectrum of atomic hydrogen.

Catheter ablation versus antiarrhythmic drugs as first-line therapy for symptomatic atrial fibrillation: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

In patients with symptomatic atrial fibrillation (AF), current international guidelines favor the use of antiarrhythmic drugs (AAD) as initial therapy for the maintenance of sinus rhythm. Previous studies have compared catheter ablation for pulmonary vein isolation versus AAD in this clinical scenario but the best first-line therapeutic option in patients with symptomatic AF candidates for rhythm control strategy remains an open issue.

Aim

To compare efficacy and safety of catheter ablation versus AAD as first-line therapy in patients with symptomatic AF.

Methods

We searched electronic databases for randomized controlled trials (RCTs) comparing catheter ablation versus AAD as first-line therapy for symptomatic AF. The primary efficacy outcome was any recurrence of atrial tachyarrhythmias. The secondary efficacy outcomes were symptomatic arrhythmic recurrences. The safety outcomes were serious adverse events related to the therapeutic regimen. Outcome events were defined according to the definition used in each original study. The effect size was estimated using a random-effect model as risk ratio (RR) and relative 95% confidence interval (CI) with the statistical software Review Manager 5.3.

Results

Five RCTs counting 997 patients (503 treated with catheter ablation and 494 with AAD) were included in the analysis. Mean age was 57 ± 3 years, 30% were female. Mean left ventricle ejection fraction was 60%±4% and mean left atrial diameter was 40 mm ± 1 mm. At baseline 52% of patients were treated with a beta-blocker and 11% with a calcium channel blocker. In the catheter ablation group 258 patients (51%) underwent cryoablation and 245 (49%) radiofrequency ablation. Median follow-up was 12 months (IQR 12-24 months). Patients treated with catheter ablation had statistically significant lower risk of atrial tachyarrhythmias recurrences (RR 0.59; 95%CI 0.45-0.76; p &lt; 0.0001 – Figure A) and of symptomatic arrhythmia recurrences (RR 0.45; 95%CI 0.25-0.80; p = 0.007 – Figure B) compared with those treated with AAD. The risk of serious adverse events related to the therapeutic regimen did not differ significantly between patients undergoing catheter ablations and those treated with AAD (RR 0.85; 95%CI 0.45-1.59 – Figure C).

Conclusions

In patients with symptomatic AF, catheter ablation as first-line therapy is associated with a reduced risk of atrial tachyarrhythmias recurrences compared with AAD, without statistically significant differences in the risk of serious adverse events related to the treatment. Abstract Figure.

Primary percutaneous coronary intervention in nonagenarian patients

Background

Given the continuous increase in life expectancy, elderly patients with ST segment elevation myocardial infarction (STEMI) are becoming a growing proportion of those referred for primary percutaneous coronary intervention (pPCI). However, this population is usually excluded from randomized trials and limited data are available to guide clinical decisions. The aim of this study-level meta-analysis was to describe and analyze the determinants of outcomes in this population.

Methods

We searched the literature for studies reporting ischemic and hemorrhagic outcomes and/or mortality in nonagenarian patients undergoing pPCI. An analysis of the heterogeneity between studies in outcome reports was performed with I2 test. A univariate meta-regression analysis was conducted to explore the relationship between outcomes of interest and classic cardiovascular risk factors, gender, previous myocardial infarction (MI), MI location, PCI characteristics, hemodynamic instability, vascular access, intra-aortic balloon pump (IABP) and Glycoprotein IIb/IIIa inhibitor (GPI) use.

Results

Overall, 15 observational studies met our inclusion criteria, with a total of 6787 patients; mean age was 92.4 and 35% were male.

The incidence of in-hospital death was 21.3%, 1.4% of our population suffered an in-hospital ischemic stroke and 11.1% faced acute renal failure; in-hospital major bleedings affected 1.7% of the population, but blood-transfusion was needed in 6.9%. Long-term mortality rate was 21.5%.

Killip III-IV at admission was related with increased in-hospital mortality (β: 0.2%; p: 0.041), but lower incidence of ARF (β: −0.6%; p: 0.004). Angiographic success was associated with a lower incidence of long-term all-cause mortality (β: −1.7%; p: 0.017) and higher incidence of ARF (β: 1.7%, p&lt;0.001). A higher number of coronary stents implanted was associated with a lower incidence of long-term all-cause mortality (β: −73%; p: 0.01). A higher long-term all-cause mortality was related with male gender (β: 0.9%; p: 0.027) and previous MI (β: 1.5%; p: 0.007). Diabetes was associated with a lower incidence of long-term all-cause mortality (β: −0.8%; p: 0.014) despite a higher incidence of in-hospital blood transfusion (β: 0.5%, p: 0.05), while a history of MI (β: 0.1%; p: 0.049), as well as the use of GPI (β: 0.04) was related with a higher incidence of in-hospital major bleeding. The use of IABP was related with a lower incidence of long-term all-cause death (β: 6.5%; p&lt;0.001) and in-hospital major bleeding (β: −0.4%; p: 0.038).

Discussion

Our meta-analysis, pooling the largest cohort of nonagenarians undergoing pPCI confirms the feasibility of urgent percutaneous coronary intervention also in this frail population. In particular, although angiographic success increased the incidence of in-hospital ARF, it was associated with a higher long-term survival underling the pivotal role of myocardial reperfusion.

Funding Acknowledgement

Type of funding source: None

D-dimer for the prediction of left atrial appendage thrombosis: daydream or reality? A meta-analysis

Introduction

Left atrial appendage thrombosis (LAAT) is a dangerous condition that mainly affects patients with atrial fibrillation (AF) or those with mitral stenosis (MS), increasing their risk of stroke. Transesophageal echocardiography (TEE) is the gold standard for the diagnosis of LAAT but some technical issues and the suboptimal sensitivity in identifying small thrombi, especially within a side lobe, can limit its clinical usefulness. Reliable non-invasive diagnostic methods could be useful in clinical practice. D-dimer, a fibrin degradation product already commonly used in the diagnostic work-up of conditions such as venous thromboembolism, may have a role as a non-invasive marker of LAAT.

Purpose

To evaluate the diagnostic performance of D-dimer for the detection of LAAT in patients with AF and/or MS, using TEE as the reference standard.

Methods

We searched the literature for studies that evaluated the ability of D-dimer to predict LAAT. For each study a 2x2 table of D-dimer positivity and LAAT presence was constructed. Sensitivity, specificity, positive predictive value and negative predictive value were calculated. Considering the different diagnostic thresholds used in the included studies, the overall sensitivity and specificity were calculated using a hierarchal summary receiver operating characteristic (HSROC) model and a SROC curve was generated.

Results

6 studies, evaluating 1380 patients of whom 154 had LAAT, were included in the analysis. The prevalence of LAAT in the studies ranged from 9% to 26%, with a median of 12%. The mean age was 60±13 years, 63% were male. The mean left atrial diameter was 43±3 mm. The D-dimer diagnostic threshold ranged from 200 mcg/l to 1150 mcg/l. The overall sensitivity calculated with the HSROC model was 85%±28% and the overall specificity was 82%±29%. The negative predictive value was 98%. Figure 1 shows the summary ROC curve: individual studies are depicted by a clear circle; the red circle marks the pooled sensitivity and specificity across the 6 studies. The red dot-dashed-curve marks the boundary of the 95% credible region for the pooled estimates of sensitivity and specificity.

Conclusions

Our analysis shows that D-dimer has a good diagnostic performance with a very high negative predictive value for LAAT and therefore it might be of clinical aid for ruling out the presence of LAAT in patients with AF and/or MS. Further studies are needed to determine the best diagnostic threshold.

Figure 1

Funding Acknowledgement

Type of funding source: None

P569Efficacy and safety of direct Xa oral inhibitors versus warfarin in patients with atrial fibrillation and cancer: a meta-analysis of randomized controlled trials

Background

Patients with cancer are at higher risk of atrial fibrillation (AF) compared with the general population. Furthermore, cancer per se and anti-cancer treatments have been associated with thromboembolic complications and increased bleeding risk. Considering that only 12% of cancer patients can achieve a stable International Normalized Ratio target and the frequent need for invasive procedures, warfarin is not an ideal option. Direct oral anticoagulants may theoretically represent a valid alternative although their use in this population has been scarcely investigated.

Purpose

To compare efficacy and safety of direct oral Xa inhibitors (DOXaI) versus warfarin in patients with atrial fibrillation and cancer.

Methods

We searched electronic databases for randomized controlled trials (RCTs) that analyzed the use of DOXaI versus warfarin in patients with AF and cancer. The primary efficacy outcome was stroke or systemic embolism (SE). The secondary efficacy outcomes were ischemic stroke, myocardial infarction and all-cause death. The primary safety outcome was major bleeding; secondary safety outcomes were major or clinically relevant non-major bleeding, intracranial bleeding and any bleeding. The net clinical benefit was estimated as the composite of the two primary outcomes. A sensitivity analysis was performed to better define the incidence of these outcomes in patients with active cancer. The statistical software ProMeta 3 was used to estimate the risk ratio with a random-effect model.

Results

3 RCTs counting a total of 3029 cancer patients (1682 on DOXaI and 1347 on warfarin), 1354  of whom with active cancer (856 on DOXaI and 502 on warfarin), were included in the analysis. Mean age was 75.6 ± 1.2 years, and 32% were female. Mean follow-up period was 2.2 ± 0.6 years. The most common cancer sites were prostate (23%), gastrointestinal tract (22.2%), breast (12.1%) and genitourinary tract (10.6%). The mean CHADS2 score was 2.9 ± 0.6 and the mean HAS-BLED score was 2.6 ± 0.4.

There were no significant differences in the risk of stroke or SE (RR 0.76; 95% CI 0.52-1.10) as well as for all the other secondary efficacy outcomes. DOXaI significantly reduced the incidence of major bleeding in the overall cancer population (RR 0.79; 95% CI 0.63-0.99; p = 0.039); this finding was consistent also in patients with active cancer (RR 0.79; 95% CI 0.59-1.05) although the effect was not statistically significant.  DOXaI also significantly reduced intracranial bleeding in overall cancer population (RR 0.12; 95% CI 0.02-0.63; p = 0.013) and any bleeding in active cancer patients (RR 0.87; 95% CI 0.77-0.98; p = 0.026). Furthermore, DOXaI significantly reduced the composite endpoints of major bleeding and stroke or SE in overall cancer population (RR 0.78; 95% CI 0.64-0.94; p = 0.008).

Conclusions

Our metanalysis shows that, in patients with atrial fibrillation and cancer, DOXaI are safer and have a similar efficacy compared with warfarin.

Abstract Figure. Primary efficacy and safety outcomes

P1915Time to freeze - An updated meta-analysis on the efficacy and safety of cryoballoon versus radiofrequency ablation for atrial fibrillation

Background and aim

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Its efficacy to prevent recurrent arrhythmias in patients nonresponsive to antiarrhythmic drugs is proven. This procedure has a higher efficacy rate in patients with paroxysmal AF (PAF) compared with persistent AF (sustained AF - SAF). Radiofrequency (RF) ablation represents a standard of care for PVI, while, cryoballoon (CB) ablation has emerged as a valid alternative therapy. The aim of the present meta-analysis was to explore the comparative efficacy, and safety of CB compared with RF ablation for AF.

Methods

We searched PubMed and EMBASE for studies that investigated the comparative efficacy and safety of CB versus RF ablation for AF. The efficacy outcome was AF recurrence after the procedure. The safety outcomes were: incidence of pericardial effusion or cardiac tamponade, permanent phrenic nerve palsy, transient phrenic nerve palsy, vascular complications and major bleedings. The performance outcomes were: procedural time and fluoroscopy time. Random-effects Risk Ratios (RRs) were estimated using a DerSimonian-Laird model. Two subgroup sensitivity analyses were performed to stratify the result on the efficacy outcome according to type of AF (PAF versus SAF) and study design (randomized clinical trial (RCT) versus observational study (OS)).

Results

12 RCT and 34 OS were included in the analysis (n=13103). Mean follow-up was 14±6 months. 37 studies included only patients with PAF, while, 2 studies included only patients with SAF and the remaining 7 studies included both patients with SAF or PAF. Overall, CB ablation reduced the incidence of AF recurrence compared with RF ablation (RR 0.85; 95% CI 0.77–0.95; P=0.002 - Figure). However, this reduction was not consistent in the RCT subgroup (RR 0.90; 95% CI 0.72–1.13) and it was marginally non-significant in the SAF subgroup (RR 0.76; 95% CI 0.57–1.01). Regarding the safety outcomes, although CB had a significantly higher rate of transient nerve palsy compared with RF procedure (RR 7.46; 95% CI 4.67–11.90) this difference became non-significant when considering permanent phrenic nerve palsy (RR 1.24; 95% CI 0.66–2.34). Moreover, CB was related to a lower incidence of pericardial effusion or cardiac tamponade compared with RF (RR 0.51; 95% CI 0.37–0.69) and there was no significant difference in vascular complications or major bleedings between the two strategies. Focusing on performance outcomes, CB ablation had a shorter procedural time compared with RF (mean difference −20 minutes; 95% CI −30 to −10; P<0.001); whereas, there was no significant difference in fluoroscopy time between the two.

CB vs. RF in preventing AF recurrence

Conclusions

This large study level meta-analysis demonstrates that CB is at least as effective as RF ablation in preventing arrhythmic recurrence both in patients with PAF and SAF. Moreover, our study suggests that CB has a safer profile and shorter procedural time compared with RF ablation.

A gas chromatography-mass spectrometry untargeted metabolomics approach to discriminate Fiore Sardo cheese produced from raw or thermized ovine milk

Thermization is a sub-pasteurization heat treatment of cheese milk (at 57-68°C for 15-30 s) aimed to reduce the number of undesirable microbial contaminants with reduced heat damage to the indigenous milk enzymes. In this work, the effects of milk thermization on the compositional parameters, proteolysis indices, free fatty acid levels, and low molecular weight metabolite profiles of ovine cheese were studied. Cheese samples at different ripening stages and produced in 2 different periods of the year were analyzed. While the effects of milk thermization on cheese macro-compositional parameters and free fatty acid levels were not evident due to the predominant effects of milk seasonality and cheese ripening stage, the gas chromatography-mass spectrometry based metabolomics approach of ovine cheese produced from raw and thermized milk highlighted strong differences at the metabolite level. Discriminant analysis applied to gas chromatography-mass spectrometry data provided an excellent classification model where cheese samples were correctly classified as produced from raw or thermized milk. The metabolites that mostly changed due to the thermization process belonged to the classes of free amino acids and saccharides. Gas chromatography-mass spectrometry-based metabolomics has proven to be a valid tool to study the effect of mild heat treatments on the polar metabolite profile in ovine cheese.

Statin use and risk of new-onset diabetes: A meta-analysis of observational studies

BACKGROUND AND AIMS

Meta-analyses of randomized control trials investigating the association between incident diabetes and statin use showed an increased risk of new-onset diabetes (NOD) from 9% to 13% associated with statins. However, short follow-up period, unpowered sample size, and lack of pre-specified diagnostic criteria for diabetes detection could be responsible of an underestimation of this risk. We conducted a meta-analysis of published observational studies to evaluate the association between statins use and risk of NOD.

METHODS AND RESULTS

PubMed, EMBASE and MEDLINE databases were searched from inception to June 30, 2016 for cohort and case-control studies with risk of NOD in users vs nonusers, on ≥1000 subjects followed-up for ≥1 year. Two review authors assessed study eligibility and risk of bias and undertook data extraction independently. Pooled estimates were calculated by a random-effects model and between-study heterogeneity was tested and measured by I² index. Furthermore, stratified analyses and the evaluation of publication bias were performed. Finally, the meta-analysis included 20 studies, 18 cohort and 2 case-control studies. Overall, NOD risk was higher in statin users than nonusers (RR 1.44; 95% CI 1.31-1.58). High between-study heterogeneity (I² = 97%) was found. Estimates for all single statins showed a class effect, from rosuvastatin (RR 1.61; 1.30-1.98) to simvastatin (RR 1.38; 1.19-1.61).

CONCLUSIONS

The present meta-analysis confirms and reinforces the evidence of a diabetogenic effect by statins utilization. These observations confirm the need of a rigorous monitoring of patients taking statins, in particular pre-diabetic patients or patients presenting with established risk factors for diabetes.

Pentraxin 3 (PTX3) plasma levels and carotid intima media thickness progression in the general population

BACKGROUND AND AIM

Pentraxin 3 (PTX3) is an essential component of the humoral arm of innate immunity and, like C-reactive protein, is independently associated with the risk of developing vascular events. Aim of this study was to investigate, in two large population-based surveys, the Bruneck Study and the PLIC Study, whether PTX3 plasma levels predict the progression of common carotid artery intima-media thickness (CCA-IMT), a surrogate marker of atherosclerosis, in the general population during 5 or 6 years of follow-up.

RESULTS

In the Bruneck Study, PTX3 plasma levels did not predict a faster progression of CCA-IMT either in the carotid artery or in the femoral artery. This finding was confirmed in the PLIC Study where subjects within the highest tertile of PTX3 did not show an increased progression of CCA-IMT. PTX3 plasma levels were also not associated with the fastest maximum IMT progression. In summary, in more than 2400 subjects from the general population, PTX3 plasma level is neither an independent predictor of progression of subclinical atherosclerosis in different arterial territories, including carotid and femoral arteries nor of incident cardiovascular events.

CONCLUSION

These findings support the relevance of investigating the predictive value of PTX3 plasma levels only in specific settings, like overt CVD, heart failure or acute myocardial infarction.

Large temperature dependence of the number of carriers in co-doped BaFe(2)As(2)

Using angle-resolved photoemission spectroscopy, we study the evolution of the number of carriers in Ba(Fe(1-x)Co(x))(2)As(2) as a function of Co content and temperature. We show that there is a k-dependent energy shift compared to density functional calculations, which is large below 100 K at low Co contents and reduces the volume of hole and electron pockets by a factor 2. This k shift becomes negligible at high Co content and could be due to interband charge or spin fluctuations. We further reveal that the bands shift with temperature, changing significantly the number of carriers they contain (up to 50%). We explain this evolution by thermal excitations of carriers among the narrow bands, possibly combined with a temperature evolution of the k-dependent fluctuations.

Low-energy models for correlated materials: bandwidth renormalization from Coulombic screening

We provide a prescription for constructing Hamiltonians representing the low-energy physics of correlated electron materials with dynamically screened Coulomb interactions. The key feature is a renormalization of the hopping and hybridization parameters by the processes that lead to the dynamical screening. The renormalization is shown to be non-negligible for various classes of correlated electron materials. The bandwidth reduction effect is necessary for connecting models to materials behavior and for making quantitative predictions for low-energy properties of solids.

How many patients need statin treatment in a low-cardiovascular-risk country? Low-density lipoprotein-cholesterol target and distance from target distribution in an Italian cohort

BACKGROUND AND AIM

To assess cardiovascular risk distribution, distribution of individual low-density lipoprotein (LDL)-cholesterol target and distance of LDL cholesterol from the target in a representative sample of the Italian population.

METHODS AND RESULTS

Cross-sectional, population-based study of a representative sample of the Italian adult population, comprising 5458 individuals (from 40 to 79 years of age, both sexes) from general practices in Italy. Of the subjects, 65.2% were in the low-cardiovascular-risk class, whereas 10.5%, 18.3% and 6.0% had moderate, high, and very high cardiovascular risk profiles, respectively; 8.2% of the subjects were treated with statins at enrolment. Of the cohort, 68.3% displayed LDL-cholesterol values below their LDL target, as calculated according to their individual risk profile. Among the 31.7% 'not at target', 42.3% were ≤ 15%, 44.3% were between 15% and 40% and 13.4% were >40% over their LDL target.

CONCLUSIONS

About two-thirds of adults in a low-cardiovascular-risk country, such as Italy, have LDL-cholesterol levels 'at target', as defined in current guidelines. Accordingly, the remaining subjects require a lifestyle or pharmacological intervention to reach their target; 24% of the total cohort, in detail, need to be treated with a statin (or to continue the prescribed statin treatment) to reach the proper LDL target. This type of data analysis might help to optimise resource allocation in preventive medicine.

Toll-like receptor signaling in amyotrophic lateral sclerosis spinal cord tissue

Increasing evidence indicates that inflammatory responses could play a critical role in the pathogenesis of motor neuron injury in amyotrophic lateral sclerosis (ALS). Recent findings have underlined the role of Toll-like receptors (TLRs) and the receptor for advanced glycation endproducts (RAGE) in the regulation of both innate and adaptive immunity in different pathologies associated with neuroinflammation. In the present study we investigated the expression and cellular distribution of TLR2, TLR4, RAGE and their endogenous ligand high mobility group box 1 (HMGB1) in the spinal cord of control (n=6) and sporadic ALS (n=12) patients. The immunohistochemical analysis of TLR2, TLR4 and RAGE showed increased expression in reactive glial cells in both gray (ventral horn) and white matter of ALS spinal cord. TLR2 was predominantly detected in cells of the microglia/macrophage lineage, whereas the TLR4 and RAGE was strongly expressed in astrocytes. Real-time quantitative PCR analysis confirmed the increased expression of both TLR2 and TLR4 and HMGB1 mRNA level in ALS patients. In ALS spinal cord, HMGB1 signal is increased in the cytoplasm of reactive glia, indicating a possible release of this molecule from glial cells. Our findings show increased expression of TLR2, TLR4, RAGE and HMGB1 in reactive glia in human ALS spinal cord, suggesting activation of the TLR/RAGE signaling pathways. The activation of these pathways may contribute to the progression of inflammation, resulting in motor neuron injury. In this context, future studies, using animal models, will be important to achieve a better understanding of these signaling pathways in ALS in view of the development of new therapeutic strategies.

Genetics of acute lung injury: past, present and future

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are major health problems worldwide. Critical care physicians have long recognized that there are patients who progress poorly despite therapy while others do unexpectedly better than it might be predicted. It is now well accepted that these responses might be related to variations in the genome. However, little is known about the genes that are responsible for susceptibility and outcome in ALI and ARDS. The search for genetic variants determining susceptibility and predicting outcome is still a developing field. The identification of important associations between genotype and clinical outcomes will have an impact on the development of more efficient genotype- or phenotype-guided therapies for patients with ALI/ARDS. Using this point of view, we will discuss some of the advances in genetic association studies in relation to the occurrence and severity of ALI/ARDS. In addition, we will also discuss the strategic and medical implications of using genetic testing to detect or predict the occurrence and prognosis of ALI/ARDS.

Issues affecting molecular staging in the management of patients with melanoma

Prediction of metastatic potential remains one of the main goals to be pursued in order to better assess the risk subgroups of patients with melanoma. Detection of occult melanoma cells in peripheral blood (circulating metastatic cells [CMC]) or in sentinel lymph nodes (sentinel node metastatic cells [SNMC]), could significantly contribute to better predict survival in melanoma patients. An overview of the numerous published studies indicate the existence of several drawbacks about either the reliability of the approaches for identification of occult melanoma cells or the clinical value of CMC and SNMC as prognostic factors among melanoma patients. In this sense, characterization of the molecular mechanisms involved in development and progression of melanoma (referred to as melanomagenesis) could contribute to better classify the different subsets of melanoma patients. Increasing evidence suggest that melanoma develops as a result of accumulated abnormalities in genetic pathways within the melanocytic lineage. The different molecular mechanisms may have separate roles or cooperate during all evolutionary phases of melanocytic tumourigenesis, generating different subsets of melanoma patients with distinct aggressiveness, clinical behaviour, and response to therapy. All these features associated with either the dissemination of occult metastatic cells or the melanomagenesis might be useful to adequately manage the melanoma patients with different prognosis as well as to better address the different melanoma subsets toward more appropriate therapeutic approaches.

Molecular alterations at chromosome 9p21 in melanocytic naevi and melanoma

BACKGROUND

The chromosome 9p21 and its CDKN locus, with the p16 tumour suppressor gene (CDKN2A), are recognized as the genomic regions involved in the pathogenesis of melanoma.

OBJECTIVES

To elucidate further the role of such regions during the different phases of melanocytic tumorigenesis.

METHODS

Tissue sections from naevi, primary and metastatic melanomas were investigated by fluorescence in situ hybridization for allelic loss at the 9p21 chromosome and by immunochemistry for p16CDKN2A expression.

RESULTS

Dysplastic naevi and primary or secondary melanomas were found to carry hemizygous deletions within the entire 9p21 region at similar frequencies (varying from 55% to 62%). Allelic deletion spanning the CDKN locus was observed at significantly increased rates moving from early (7%) to advanced (28%) primary melanomas and to secondary melanoma lesions (37%) (P=0.018). Also, inactivation of the p16 gene (CDKN2A) was absent in naevi and present at steadily increasing rates moving from primary melanomas (7% early lesions to 17% advanced lesions) to melanoma metastases (62%) (P=0.004).

CONCLUSIONS

Our findings indicate that, in a model of sequential accumulation of genetic alterations, 9p21 deletions may play a role in melanocytic transformation and tumour initiation whereas rearrangements at the CDKN locus, and p16 gene (CDKN2A) inactivation may contribute to tumour progression.

Mitochondrial DNA assessment in adipocytes and peripheral blood mononuclear cells of HIV-infected patients with lipodystrophy according to a validated case definition

BACKGROUND

Several studies have compared mitochondrial DNA (mtDNA) content in tissue from HIV-1-infected patients on highly active antiretroviral therapy with and without evidence of lipodystrophy, the diagnosis of which was based on subjective clinical assessment.

OBJECTIVES

The aim of this study was to assess the utility of mtDNA quantification as a marker of HIV-associated lipodystrophy as diagnosed using a published validated case definition.

METHODS

We assessed mtDNA content in adipocytes from both thigh and lumbar subcutaneous adipose tissue (n=19), and in peripheral blood mononuclear cells (PBMC) (n=26), obtained from 26 HIV-1-infected patients classified as having lipodystrophy (n=17) or not having lipodystrophy (n=9) according to the validated definition derived from the Lipodystrophy Case Definition Study.

RESULTS

The adipocyte and PBMC mtDNA contents did not significantly differ between patients with and without lipodystrophy. Lipodystrophy patients had been treated for significantly longer times, especially with dideoxynucleoside analogues. In both groups, the thigh adipocyte mtDNA content was significantly greater than that of the lumbar region. When all patients were considered together, a statistically significant negative correlation was found between thigh adipocyte mtDNA content and stavudine treatment duration.

CONCLUSIONS

Longer exposure to dideoxynucleoside analogues was associated with lipodystrophy, and longer exposure to stavudine was correlated with lower mtDNA content in thigh adipocytes. However, a single measurement of adipocyte mtDNA content in this limited sample of patients could not distinguish between patients with and without clinical lipodystrophy. The observed variation in mtDNA content between different subcutaneous adipose tissue depots argues for harmonization of future studies regarding which depot to biopsy.

Serial RT-PCR detection of circulating tumour cells as a marker of disease progression in patients with malignant melanoma

18009

Background: Detection of circulating malignant cells (CMCs) through a reverse transcriptase-polymerase chain reaction (RT-PCR) assay seems to be a demonstration of systemic disease. We here evaluated the prognostic role of RT-PCR assays in serially-taken peripheral blood samples from patients with malignant melanoma (MM). Methods: One hundred forty-nine melanoma patients with disease stage ranging from I to III were consecutively collected in 1997. A multi-marker RT-PCR assay was used on peripheral blood samples obtained at time of diagnosis and every 6 months during the first two years of follow-up (total: 5 samples). Univariate and multivariate analyses were performed after 83 months of median follow-up. Results: Detection of at least one circulating mRNA marker was considered a signal of the presence of CMC (referred to as PCR-positive assay). A significant correlation was found between the rate of recurrences and the increasing number of PCR-positive assays (P = 0.007). Presence of CMC in a high number (≥2) of analysed blood samples was significantly correlated with a poor clinical outcome (disease-free survival: P = 0.019; overall survival: P = 0.034). Multivariate analysis revealed that presence of a PCR-positive status does play a role as independent prognostic factors for overall survival in melanoma patients, adding precision to the predictive power of the disease stage. Conclusions: Our findings indicated that serial RT-PCR assay may identify a high risk subset of melanoma patients with occult cancer cells constantly detected in blood circulation. Prolonged presence of CMCs seems to act as a surrogate marker of disease progression or a sign of more aggressive disease.

No significant financial relationships to disclose.

Greater and more rapid depletion of mitochondrial DNA in blood of patients treated with dual (zidovudine+didanosine or zidovudine+zalcitabine) vs. single (zidovudine) nucleoside reverse transcriptase inhibitors

BACKGROUND

Most toxicities associated with nucleoside analogue reverse transcriptase inhibitors (NRTIs) are thought to result from mitochondrial toxicity. These toxicities include peripheral neuropathy, pancreatitis, lactic acidosis, and peripheral lipoatrophy. Unfortunately, there are no validated laboratory markers for clinically assessing, let alone predicting, the onset of mitochondrial toxicity associated with NRTI therapy.

OBJECTIVES

To provide preliminary evidence of the potential clinical utility of an assay which has been developed for quantifying mitochondrial DNA (mtDNA) in clinical samples from HIV-infected patients.

METHODS

A single-tube duplex real-time DNA-nucleic acid sequence-based amplification (NASBA) assay (Mitox, Primagen, Amsterdam, the Netherlands) was used to quantify mtDNA in cryopreserved peripheral blood mononuclear cells (PBMC) obtained from HIV-1-infected patients during their prior participation in a randomized placebo-controlled trial comparing zidovudine (ZDV) monotherapy with combinations of ZDV plus either dideoxycytidine (ddC) or didanosine (ddI) (the Delta trial). Patients were antiretroviral naïve prior to entering the trial. Samples obtained during the initial 48 weeks of treatment were tested.

RESULTS

A significant decline of mtDNA, both in an intent-to-treat and in an as-treated analysis, was observed in patients treated with ZDV+ddC and ZDV+ddI, but not with ZDV alone, consistent with the results expected from the degree of mtDNA depletion described for each of these drugs in vitro.

CONCLUSIONS

This single-tube duplex real-time DNA-NASBA assay was shown to measure mtDNA accurately in PBMC. Treatment with a combination of two NRTIs was associated with greater reductions in mtDNA than obtained for ZDV monotherapy. The relevance of these results in predicting treatment toxicity requires further evaluation.