House-resting Anopheles mosquitoes are targeted for vector control interventions; however, without proper species identification, the importance of these Anopheles to malaria transmission is unknown. ...Anopheles longipalpis, a non-vector species, has been found in significant numbers resting indoors in houses in southern Zambia, potentially impacting on the utilization of scarce resources for vector control. The identification of An. longipalpis is currently based on classical morphology using minor characteristics in the adult stage and major ones in the larval stage. The close similarity to the major malaria vector An. funestus led to investigations into the development of a molecular assay for identification of An. longipalpis. Molecular analysis of An. longipalpis from South Africa and Zambia revealed marked differences in size and nucleotide sequence in the second internal transcribed spacer (ITS2) region of ribosomal DNA between these two populations, leading to the conclusion that more than one species was being analysed. Phylogenetic analysis showed the Zambian samples aligned with An. funestus, An. vaneedeni and An. parensis, whereas the South African sample aligned with An. leesoni, a species that is considered to be more closely related to the Asian An. minimus subgroup than to the African An. funestus subgroup. Species-specific primers were designed to be used in a multiplex PCR assay to distinguish between these two cryptic species and members of the An. funestus subgroup for which there is already a multiplex PCR assay.
Abstract Background Catheter ablation (CA) with pulmonary vein isolation (PVI) is an optimal treatment option in patients with paroxysmal atrial fibrillation (AF). PVI alone in patients with ...persistent AF has proved to have suboptimal results. Ablation of additional atrial structures, such as posterior wall (PW) and left atrial appendage has been investigated as a tool to improve procedural efficacy. Recently very high-power short-duration (vHPSD) ablation was developed to allow rapid PVI, limiting complication through the maximization of resistive heating, and minimization of conductive heating. Objectives Compare PVI plus PWI using vHPSD versus standard-power (SP) ablation index-guided CA among consecutive patients with persistent AF Methods Forty consecutive patients underwent PVI plus PW isolation using vHPSD, compared to 40 controls underwent standard power (SP) PVI plus PW isolation. The primary efficacy endpoint outcome was recurrence of atrial tachyarrhythmias after a 3-month blanking period. The primary safety outcome was a composite of major complications within 30 days of CA. Results Treated patients have a median age of 62.8±9 years, 68 (85%) are male. Median left atrial volume is 42.4 (36-50) ml/m2. 61 (78.8%) patients had never undergone catheter ablation before. There are no statistically significant differences between groups. PW isolation was obtained more commonly in the vHPSD compared to the SP group (98% vs. 75%, p=0.007), despite shorter procedure and fluoroscopy times (p<0.001). Survival free from recurrent atrial tachyarrhythmias at 18 months was 68% in the vHPSD and 47% in SP groups, respectively (log-rank p=0.071), without major adverse events. The vHPSD approach was significantly associated with reduced risk of recurrent AF at multivariable analysis (HR, 0.39, p=0.030). Conclusions The results show feasibility and safety of posterior wall vHPSD ablation for persistent AF using this new temperature-controlled catheter without intraprocedural and periprocedural major complications at follow-up. vHPSD ablation for PW isolation may be more effective in term of atrial tachyarrhythmias recurrences with a trend for superior efficacy. However, this remains a single center experience in a small group of patients. Comparative trials involving greater number of patients with long-term follow-up are necessary to definitive results.
Abstract Background Pulsed Field ablation (PFA) has recently emerged as a treatment strategy for patients with atrial fibrillation (AF) and early studies showed promising procedural data and durable ...pulmonary vein isolation (PVI). However, Very High-Power Short-Duration ablation (VHPSD) has previously reported good efficiency and mid-term outcomes, and only a few works compared these two procedures, especially in patients with persistent AF. Objective Our aim is to compare these different modalities of transcatheter ablation in patients with persistent AF, focusing mainly on some procedural aspects, safety and efficacy. Methods We performed a retrospective observational study enrolling all consecutive patients with persistent AF from September 2021 to May 2023 undergoing transcatheter ablation with PFA or VHPSD. In the first group, PVI was achieved by 2kV pulses with eight applications to each vein using both catheter configurations, while isolation of the posterior wall of the left atrium was achieved by applications through the only "flower" configuration; additional lesions were then added at the operator's discretion. In the second group, PVI was achieved by delivering 90W radiofrequency pulses for 4 seconds in the posterior portions of the left atrium and 50W pulses in the anterior region of the pulmonary veins; additional lesions were occasionally applied. All patients received general anaesthesia or deep sedation with fentanyl and dexmedetomidine. Results A total of 79 patients were included, n = 24 (30%) in the PFA group and N = 55 (70%) in the VHPSD one: early persistent AF (n= 2 8,3%; N = 7 12,7%), persistent AF (n= 17 70,8%; N = 36 65,5%), long-standing persistent AF (n= 5 20,8%; N = 12 21,8%). The two populations showed similar clinical features: CHA2DS2-VASc (median value 3 0-6 in PFA vs 2 0-6 in VHPSD, p = 0,10), indexed left atrial volume (mean value 42,6 ml/m² in PFA vs 42,4 ml/m² in VHPSD, p = 0,07) and EF (mean value 55,4% in PFA vs 54,8% in VHPSD, p = 0,33). PVI was successfully achieved in all patients. Nevertheless, the PFA group was associated with shorter procedural duration (92,1 ± 36,9 vs 134,2 ± 36,1 minutes, p = 0,00001) but longer fluoroscopy time (25,5 ± 9,3 vs 17,4 ± 11,5 minutes, p = 0,001); it also showed a lower rate of minor complications (n = 1 4,2% vs N = 3 5,5%, p = 0,057), even though serious complications were not observed in either group. After a median follow-up of 14 (9-26) months, n = 19 79.2% in the PFA and N = 43 78.2% in the VHPSD population were free of any atrial arrhythmia (p = 0,92). Conclusion PFA allows faster procedures, representing a major advantage for the operator and the patient, who is at lower risk of peri-procedural complications. On the other hand, VHPSD correlates with shorter fluoroscopy times, reducing exposure to ionizing radiation. Finally, the two procedures show similar mid-term efficacy in terms of recurrence-free time.
Abstract Background Pulsed Field Ablation (PFA) is an innovative technology to perform atrial fibrillation (AF) catheter ablation. No form of thermal energy is used, but an irreversible ...electroporation mechanism that causes selective cardiomyocytes death, sparing the cells of adjacent tissues. There are few data in the literature about peri-procedural trend of myocardium-necrosis laboratory data in patients undergoing PFA versus those with radiofrequency (RF). Purpose Compare the short-term safety and the peri-procedural trend of myocardium-necrosis laboratory data in patients undergoing PFA with those undergoing standard-power (40W) RF catheter ablation. Methods 50 patients undergoing paroxysmal AF catheter ablation with pulmonary veins isolation were retrospectively enrolled, 25 treated with PFA and 25 with RF (matched for age, sex, BMI, left atrium size). The PFA protocol involved four two-second deliveries with the penta-spline catheter in the "basket" and in the "flower" configuration; about RF ablation, circular lesions were carried out at the antrum of each pulmonary vein. All patients underwent serial blood samples including troponin I (TnI, n.v. 0-50 ng/L) and CKMB (n.v 0-5 ng/mL) at time 0 and at 3, 24 and 48 post-procedure hours. Complication were evaluated at pre-discharge visit and at 3-month follow-up. Results The clinical and echocardiographic patient’s characteristics are summarized in Table 1. The TnI and CKMB baseline values were within normal range for all patients, both those treated with PFA and those treated with RF, and there were no statistically significant differences between the two group. Regarding the TnI and CKMB values temporal increase, a statistically significant increase was observed in patients treated with PFA (Table 2). The TnI percentage decrease over the 48 hours in RF-treated patients, although not statistically significant, is slower compared to patients treated with PFA. This data could be explained by considering that PFA causes acute damage (myocardiocytes necrosis by electroporation) with less inflammation and a less progressive nature, while RF causes damage with greater irritation and progression (coagulative necrosis) that may result in myocardial necrosis even in the subsequent hours. Despite evidence of greater myocardial necrosis, there were not procedural complications in those treated with PFA. Therefore, the TnI increase is indicative of selective myocardial damage, likely more antral. Conclusion The increase of myocardio-necrosis laboratory data appears to be higher using PFA compared to RF, and it is not associated with greater adverse events. The trend of the myocardio-necrosis laboratory data shows different reduction curves between PFA and RF, probably related to different ablation power source; these data will need to be re-analysed with a greater number of cases.Table 1Table 2
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
The recent introduction of Omnipolar Technology (OT) has the potential to improve ventricular substrate characterization. ...In fact, the amplitude of omnipolar electrograms is less dependent of the propagation direction of the recorded wavefront than that of bipolar electrograms, potentially increasing the sensitivity for the detection of viable myocardium by electroanatomical voltage mapping (EVM).
Purpose
To assess the presence and extension of dense scar regions and low-voltage areas in omnipolar voltage (OV) maps of the left ventricle (LV) as compared to standard bipolar endocardial maps and cardiac magnetic resonance (CMR)-derived pixel signal intensity (PSI) maps, among patients undergoing EVM-guided endomyocardial biopsy (EMB).
Methods
The study included 10 patients undergoing LV substrate mapping and EVM-guided EMB at our institution using the Advisor HD Grid mapping catheter. Before the procedure, contrast enhanced-CMR was obtained for each patient and PSI maps were derived from late gadolinium enhancement sequences with the ADAS-VT software. Scar core and border zone areas were measured in PSI endocardial (10-40% of wall thickness) maps and compared to dense scar regions (<0.5 mV) and low-voltage areas (0.5-1.5 mV) measured by standard bipolar endocardial mapping and OV endocardial mapping, respectively. Continuous variables were checked for normality with the Shapiro-Wilk test, and are reported as mean±standard deviation or median 1st-3rd quartile, as appropriate. Statistical comparisons among the three types of mapping (PSI mapping, standard bipolar, and OV) were performed with Friedman test with post-hoc sign test, as appropriate. P values<0.05 were considered statistically significant, and all analyses were performed with the software RStudio.
Results
The indication for EVM-guided EMB was a clinical suspicion of arrhythmogenic or inflammatory cardiomyopathy in all cases. Dense scar regions and low voltage areas detected by OV (dense scar: 2.2 1.2-6.9 cm2; low voltage areas: 8±3.8 cm2) and standard bipolar mapping (dense scar: 3.4 2.3-9.6 cm2; low voltage areas: 8.4±4 cm2) were similar to scar core and border zone areas shown by PSI maps (scar core: 1.60.6-2.9 cm2; border zone: 3.93.7-7.6 cm2; all p=NS). However, dense scar regions were less widespread with OV mapping that with standard bipolar mapping (Friedman test p=0.07; adjusted p=0.006, Figure). The diagnostic yield of EMB measured 80%, whereas mean procedural and fluoroscopy times were 136±30 min and 11±4 min, respectively.
Conclusion
OV mapping allowed a refinement of endocardial substrate maps of the LV as compared to standard bipolar mapping, by reducing the dependency of electrogram amplitude on the direction of propagation, thus allowing the detection of viable myocardium even in bipolar scar regions. Therefore, OV mapping may soon become a preferred approach for EVM-guided EMB.
Abstract
Funding Acknowledgements
No funding
Introduction
Multiple left ventricular pacing strategies have been suggested for improving response to cardiac resynchronization therapy (CRT). However, ...these programming strategies can be obtained by accepting configurations with high pacing threshold and accelerated battery drain. We assessed the feasibility of predefined pacing programming protocols and we evaluated their impact on device longevity and their cost-impact.
Methods
We estimated battery longevity in 167 CRT-D (RESONATE, Boston Scientific) patients based on measured pacing parameters and according to multiple programming strategies: single-site pacing associated with lowest threshold, non-apical location, longest interventricular delay, pacing from two electrodes. To determine the economic impact of each programming strategy, we applied the results of a published model-based cost analysis to a 15-year time-horizon.
Results
Selecting the electrode with the lowest threshold resulted in a median device longevity of 11.5 years. Non-apical pacing and interventricular delay maximization were feasible in most patients (99% non-apical pacing, 65% RV-to-LV interval >80ms), and were obtained at the price of a few months of battery life. Device longevity of >10 years was preserved in 87% of cases of non-apical pacing and in 77% on pacing at the longest interventricular delay. The mean reduction in battery life when the second electrode was activated was 1.5 years. Single-site pacing strategies increased the therapy cost by 4-6%, and multi-site pacing by 12-13%, in comparison with the best-case scenario.
Conclusions
Modern CRT-D systems ensure effective pacing and allow multiple optimization strategies for maximizing service life or for enhancing effectiveness. Single- or multi-site pacing strategies can be implemented without compromising device service life and at an acceptable increase in therapy cost.
Abstract Figure. Image1
Emerging evidence suggests that severe form of coronavirus disease 2019 (COVID-19) is mediated, in part, by a hypercoagulable state characterized by micro- and macro-vascular thrombotic angiopathy. ...Although venous thrombotic events in COVID-19 patients have been well described, data on arterial thrombosis (AT) in these patients is still limited. We, therefore, conducted a rapid systematic review of current scientific literature to identify and consolidate evidence of AT in COVID-19 patients.
A systematic search of literature was conducted between November 1, 2019, and June 9, 2020, on PubMed and China National Knowledge Infrastructure to identify potentially eligible studies.
A total of 27 studies (5 cohort, 5 case series, and 17 case reports) describing arterial thrombotic events in 90 COVID-19 patients were included. The pooled incidence of AT in severe/critically ill intensive care unit-admitted COVID-19 patients across the 5 cohort studies was 4.4% (95% confidence interval 2.8-6.4). Most of the patients were male, elderly, and had comorbidities. AT was symptomatic in >95% of these patients and involved multiple arteries in approximately 18% of patients. The anatomical distribution of arterial thrombotic events was wide, occurring in limb arteries (39%), cerebral arteries (24%), great vessels (aorta, common iliac, common carotid, and brachiocephalic trunk; 19%), coronary arteries (9%), and superior mesenteric artery (8%). The mortality rate in these patients is approximately 20%.
AT occurs in approximately 4% of critically ill COVID-19 patients. It often presents symptomatically and can affect multiple arteries. Further investigation of the underlying mechanism of AT in COVID-19 would be needed to clarify possible therapeutic targets.
PDF
