Initial clinical experience with the novel POLARx FIT cryoballoon system for pulmonary vein isolation in patients with atrial fibrillation.

Background: The POLARx FIT system (Boston Scientific, MA, USA) is a novel cryoballoon (CB) ablation technology in which the balloon diameter can be expanded from 28 to 31 mm. The aim of this study was to compare the benefits and safety of the new POLARx FIT system to those of the existing POLARx system currently in use for pulmonary vein (PV) isolation (PVI) in patients with atrial fibrillation. Methods: The first 70 consecutive patients who underwent CB-based PVI with the POLARx FIT system were retrospectively compared with 200 consecutive patients treated with the POLARx system at Sakakibara Heart Institute from October 2021 to May 2023. Results: The POLARx FIT system yielded a higher mean ± standard deviation nadir temperature in the right inferior PV (-59.2 ± 5.29 °C vs. - 62.0 ± 5.08 °C, p = 0.006), but this required a balloon size reduction to 28 mm in 30 % of cases. No significant differences were detected in the time to isolation and thaw time of any PV between the two groups. After the CB-based PVI procedure, no residual PV carina potentials were observed with the POLARx FIT system, whereas 4/20 were with the POLARx system (p = 0.04). Conclusions: The POLARx FIT system had comparable effectiveness and safety to the basic POLARx system. This technology may improve the ablation area, including the PV carina. However, the 31-mm balloon alone was not sufficient to isolate certain PVs.

Phrenic nerve injury after atrial fibrillation ablation: different recovery courses among cryoballoon, laser balloon, and radiofrequency ablation.

BACKGROUND: Phrenic nerve injury (PNI) is one of the common complications in atrial fibrillation (AF) ablation, which often recovers spontaneously. However, the course of its recovery has not been examined fully, especially in regard to the different ablation methods. We sought to compare the recovery course of PNI in cryoballoon, laser balloon, and radiofrequency ablation. METHODS: This multicenter retrospective study analyzed 355 patients who suffered from PNI during AF ablation. PNI occurred during cryoballoon ablation (CB group) and laser balloon ablation (LB group) for a pulmonary vein isolation in 288 and 20 patients, and radiofrequency ablation for a superior vena cava (SVC) isolation (RF-SVC group) in 47 patients, respectively RESULTS: There was a significant difference in the estimated probability of PNI recovery after the procedure between the methods (p = 0.01). PNI recovered significantly earlier in the CB group, especially within 24 h and 3 months post-procedure (the percentage of the recovery within 24 h and 3 months: 49.7% and 71.5% in the CB group, 15.0% and 22.2% in the LB group, and 23.4% and 41.9% in the RF-SVC group, respectively). Persistent PNI after 12 months was observed in only seven patients in the CB group, one in the LB group, and four in the RF-SVC group, respectively. CONCLUSION: PNI rarely persists over 12 months after AF ablation; however, there is a difference in the timing of its recovery. PNI recovers quicker with cryoballoon ablation than with laser balloon ablation or radiofrequency ablation of the SVC.

Associations between fluid overload and outcomes in critically ill patients with acute kidney injury: a retrospective observational study.

Increased fluid overload (FO) is associated with poor outcomes in critically ill patients, especially in acute kidney injury (AKI). However, the exact timing from when FO influences outcomes remains unclear. We retrospectively screened intensive care unit (ICU) admitted patients with AKI between January 2011 and December 2015. Logistic or linear regression analyses were performed to determine when hourly %FO was significant on 90-day in-hospital mortality (primary outcome) or ventilator-free days (VFDs). In total, 1120 patients were enrolled in this study. Univariate analysis showed that a higher %FO was significantly associated with higher mortality from the first hour of ICU admission (odds ratio 1.34, 95% confidence interval 1.15-1.56, P < 0.001), whereas multivariate analysis adjusted with age, sex, APACHE II score, and sepsis etiology showed the association was significant from the 27th hour. Both univariate and multivariate analyses showed that a higher %FO was significantly associated with shorter VFDs from the 1st hour. The significant associations were retained during all following observation periods after they showed significance. In patients with AKI, a higher %FO was associated with higher mortality and shorter VFDs from the early phase after ICU admission. FO should be administered with a physiological target or goal in place from the initial phase of critical illness.

Ultrasound assessment is useful for evaluating balloon volume of resuscitative endovascular balloon occlusion of the aorta.

BACKGROUND: Endovascular balloon occlusion of the aorta (EBOA) increases proximal arterial pressure but may also induce life-threatening ischemic complications. Although partial REBOA (P-REBOA) mitigates distal ischemia, it requires invasive monitoring of femoral artery pressure for titration. In this study, we aimed to titrate P-REBOA to prevent high-degree P-REBOA using ultrasound assessment of femoral arterial flow. METHODS: Proximal (carotid) and distal (femoral) arterial pressures were recorded, and perfusion velocity of distal arterial pressures was measured by pulse wave Doppler. Systolic and diastolic peak velocities were measured among all ten pigs. Total REBOA was defined as a cessation of distal pulse pressure, and maximum balloon volume was documented. The balloon volume (BV) was titrated at 20% increments of maximum capacity to adjust the degree of P-REBOA. The distal/proximal arterial pressure gradient and the perfusion velocity of distal arterial pressures were recorded. RESULTS: Proximal blood pressure increased with increasing BV. Distal pressure decreased with increasing BV, and distal pressure sharply decreased by > 80% of BV. Both systolic and diastolic velocities of the distal arterial pressure decreased with increasing BV. Diastolic velocity could not be recorded when the BV of REBOA was > 80%. CONCLUSION: The diastolic peak velocity in the femoral artery disappeared when %BV was > 80%. Evaluation of the femoral artery pressure by pulse wave Doppler may predict the degree of P-REBOA without invasive arterial monitoring.

Prehospital stroke-scale machine-learning model predicts the need for surgical intervention.

While the development of prehospital diagnosis scales has been reported in various regions, we have also developed a scale to predict stroke type using machine learning. In the present study, we aimed to assess for the first time a scale that predicts the need for surgical intervention across stroke types, including subarachnoid haemorrhage and intracerebral haemorrhage. A multicentre retrospective study was conducted within a secondary medical care area. Twenty-three items, including vitals and neurological symptoms, were analysed in adult patients suspected of having a stroke by paramedics. The primary outcome was a binary classification model for predicting surgical intervention based on eXtreme Gradient Boosting (XGBoost). Of the 1143 patients enrolled, 765 (70%) were used as the training cohort, and 378 (30%) were used as the test cohort. The XGBoost model predicted stroke requiring surgical intervention with high accuracy in the test cohort, with an area under the receiver operating characteristic curve of 0.802 (sensitivity 0.748, specificity 0.853). We found that simple survey items, such as the level of consciousness, vital signs, sudden headache, and speech abnormalities were the most significant variables for accurate prediction. This algorithm can be useful for prehospital stroke management, which is crucial for better patient outcomes.

Spatial relationship of localized sources of persistent atrial fibrillation identified by a unipolar-based automated algorithm to complex fractionated atrial electrocardiograms and atrial low voltage areas.

INTRODUCTION: Spatial characteristics of localized sources of persistent atrial fibrillation (AF) identified by unipolar-based panoramic mapping software (CARTOFINDER) remain unclear. We evaluated spatial characteristics of bi-atrial AF localized sources in relation to complex fractionated atrial electrocardiograms (CFAEs) and atrial low voltage area (LVAs) (≤0.35 mV during AF). METHODS AND RESULTS: Twenty consecutive patients with persistent AF underwent bi-atrial voltage, CFAE, and CARTOFINDER mapping before the beginning of ablation (18 [90%] patients, initial procedure; 2 [10%] patients, repeat procedure). CFAEs were recorded using the interval confidence level (ICL) mode and defined as sites with a confidence level of ≥80% of maximal ICL number. We elucidated the following: (1) differences in the rate of AF localized sources and CFAEs inside or outside the atrial LVAs; (2) distribution of AF localized sources and CFAEs; and (3) distance between the closest points of AF localized sources and CFAEs. A total of 270 AF localized sources and 486 CFAEs were identified in 20 patients. AF localized sources were confirmed more often outside atrial LVAs than CFAEs (71% vs. 46% outside LVA, p < .001). AF localized sources and CFAEs were diffusely distributed without any tendency in bi-atria. Mean distance between closest AF localized sources and CFAEs was 22 ± 8 mm. CONCLUSION: AF localized sources identified by CARTOFINDER are different therapeutic targets as compared to CFAEs and could be confirmed both inside and outside atrial LVAs.

Prehospital diagnostic algorithm for acute coronary syndrome using machine learning: a prospective observational study.

Rapid and precise prehospital recognition of acute coronary syndrome (ACS) is key to improving clinical outcomes. The aim of this study was to investigate a predictive power for predicting ACS using the machine learning-based prehospital algorithm. We conducted a multicenter observational prospective study that included 10 participating facilities in an urban area of Japan. The data from consecutive adult patients, identified by emergency medical service personnel with suspected ACS, were analyzed. In this study, we used nested cross-validation to evaluate the predictive performance of the model. The primary outcomes were binary classification models for ACS prediction based on the nine machine learning algorithms. The voting classifier model for ACS using 43 features had the highest area under the receiver operating curve (AUC) (0.861 [95% CI 0.775-0.832]) in the test score. After validating the accuracy of the model using the external cohort, we repeated the analysis with a limited number of selected features. The performance of the algorithms using 17 features remained high AUC (voting classifier, 0.864 [95% CI 0.830-0.898], support vector machine (radial basis function), 0.864 [95% CI 0.829-0.887]) in the test score. We found that the machine learning-based prehospital algorithms showed a high predictive power for predicting ACS.

Posterior reversible encephalopathy syndrome (PRES) of the isolated brainstem.

A 71-year-old man had disordered consciousness whose Glasgow Coma Scale was E4V1M5. His blood pressure was high, but there was no abnormality in the cerebrospinal fluid examination. The MRI finding reveals a high-intensity area at the pons without the blood flow interruption. Thus, he has diagnosed with brainstem PRES.

A prehospital diagnostic algorithm for strokes using machine learning: a prospective observational study.

High precision is optimal in prehospital diagnostic algorithms for strokes and large vessel occlusions. We hypothesized that prehospital diagnostic algorithms for strokes and their subcategories using machine learning could have high predictive value. Consecutive adult patients with suspected stroke as per emergency medical service personnel were enrolled in a prospective multicenter observational study in 12 hospitals in Japan. Five diagnostic algorithms using machine learning, including logistic regression, random forest, support vector machine, and eXtreme Gradient Boosting, were evaluated for stroke and subcategories including acute ischemic stroke with/without large vessel occlusions, intracranial hemorrhage, and subarachnoid hemorrhage. Of the 1446 patients in the analysis, 1156 (80%) were randomly included in the training (derivation) cohort and cohorts, and 290 (20%) were included in the test (validation) cohort. In the diagnostic algorithms for strokes using eXtreme Gradient Boosting had the highest diagnostic value (test data, area under the receiver operating curve 0.980). In the diagnostic algorithms for the subcategories using eXtreme Gradient Boosting had a high predictive value (test data, area under the receiver operating curve, acute ischemic stroke with/without large vessel occlusions 0.898/0.882, intracranial hemorrhage 0.866, subarachnoid hemorrhage 0.926). Prehospital diagnostic algorithms using machine learning had high predictive value for strokes and their subcategories.

Urinary Liver-Type Fatty Acid-Binding Protein Level as a Predictive Biomarker of Acute Kidney Injury in Patients with Acute Decompensated Heart Failure.

BACKGROUND: There are no biological markers to predict the onset of acute kidney injury (AKI) in patients with acute decompensated heart failure (ADHF). Liver-type fatty acid-binding protein (L-FABP) levels are markedly upregulated in the proximal tubules after renal ischemia. We investigated whether urinary L-FABP is a suitable marker to predict AKI in ADHF patients. METHODS: We examined 281 consecutive patients with ADHF. Serum creatinine (Cr) and L-FABP levels were measured at admission and 24 and 48 h after admission. RESULTS: AKI developed in 104 patients (37%). Urinary L-FABP levels at admission were significantly higher in patients with AKI than in those without (33.0 vs. 5.2 µg/g Cr; p < 0.001). Multivariate analysis showed that baseline urinary L-FABP level was an independent predictor of AKI in ADHF patients (odds ratio 1.08, 95% confidence interval 1.05-1.12; p < 0.001). Receiver operating characteristic analysis showed that baseline urinary L-FABP level exhibited 94.2% sensitivity and 87.0% specificity at a cutoff value of 12.5 µg/g Cr. CONCLUSIONS: Urinary L-FABP level is useful for predicting the onset of AKI in patients with ADHF. The results of our study could help clinicians diagnose AKI in ADHF patients earlier, leading to possible improvements in the treatment of this group of patients.

The Efficacy of Isochronal 3D Mapping-Based Ablation of Ventricular Arrhythmia.

Treatment of ventricular arrhythmias (VAs) commonly involves ablating sites showing electrograms with the earliest activity relative to the VA, but there is no threshold value for prematurity guaranteeing success. Ablation of sites with great prematurity can still result in failure.We hypothesized that isochronal map area (ISCA), derived from isochrones indicating electrogram prematurity, could help identify ablation targets in VA patients, as well as predict outcome. Specifically, we hypothesized that smaller ICSA for a given prematurity value would indicate a shallower arrhythmogenic focus leading to a higher likelihood of successful ablation.We studied ICSA in 29 patients (12 males, 57 [17-65] years old) undergoing VA ablation. The VAs originated from the right and left ventricles in 11 and 18 patients, respectively. The earliest activation site of the VAs, ECG morphology of sinus beats and premature ventricular complexes (PVCs), and ISCA of activation preceding PVCs were evaluated.RF ablation at the site showing earliest prematurity resulted in VA elimination in 21 patients (success group). The 5-ms ISCA was smaller in the success group than in the failure group (0.2 [0.1-0.6] versus 1.0 [0.8-1.5] cm2, respectively; P < 0.01). No significant difference was noted in prematurity itself (36 [30-45] versus 30 [29-33] ms, respectively; P = 0.07). The cut-off value of the 5 ms ISCA for successful RF ablation was 0.7 cm2 with 87.5% sensitivity and 85.6% specificity.Isochrones of activity preceding PVCs appear to contain information beyond prematurity values and may help dictate suitable areas for successful ablation of VAs.

Empiric Antibiotic Therapy for Severe Sepsis and Septic Shock.

BACKGROUND: A retrospective study was conducted to investigate the validity and the effectiveness of early empiric antibiotic and de-escalation therapy for the treatment of severe sepsis and septic shock patients in the intensive care unit (ICU). METHODS: Patients admitted to the ICU at Chiba University Hospital from January 1, 2010, to December 31, 2012, for the treatment of severe sepsis or septic shock were selected for analysis. RESULTS: One-hundred and ten patients were enrolled for the analysis. Carbapenems were selected most frequently (57.3%), followed by cephalosporins (22.7%), and penicillins (21.8%). Empiric antibiotic therapy was appropriate for 85 (77.3%) patients. Mortality rates for patients with inappropriate empiric therapy was 36.8%, whereas mortality rates for patients with appropriate empiric therapy was 17.5%. Among the patients with appropriate empiric antibiotic administration, de-escalation was associated with lower mortality rates of 5.0% for severe sepsis and 9.7% for septic shock patients. The mortality rates for the no de-escalation group were 19.0% and 35.7%, respectively. CONCLUSION: Empiric antibiotic therapy was acceptable for severe sepsis and septic shock patients treated in the ICU. The appropriate selection of empiric antibiotics was related to a greater rate of de-escalation and better survival. The risk of multi-drug-resistant bacterial infections was not as high as expected, but will need further attention in the future.

Intrahospital transport of mechanically ventilated intensive care patients using new equipment attached to a transfer board.

Aim: Multiple lines and tubes often complicate bed transfer in critically ill patients. To solve this problem, the authors developed medical equipment attached to a transfer board ("transfer board tree") that integrates the patient, transfer board, and medical equipment. The objective of this study was to evaluate the efficiency and safety of the transfer board tree. Methods: Forty mechanically ventilated patients (20 transfer board tree, 20 conventional) in the intensive care unit who were transported for computed tomography were enrolled. Transfer times and adverse events were recorded. Results: Transfer board tree patients had significantly shorter transfer times. There were two adverse events only in the conventional group. Conclusions: The transfer board tree enables rapid intrahospital transport of intensive care patients with sufficient monitoring.

Gram-scale synthesis of nickel(II) norcorrole: the smallest antiaromatic porphyrinoid.

Small is beautiful: A ring-contracted sister of porphyrin, norcorrole, has been synthesized efficiently as a stable molecule by a nickel-templated strategy. The norcorrole complex is stable but exhibits a distinct antiaromatic character according to the Hückel rule. Oxidation of the norcorrole complex provides an aromatic oxacorrole complex.

Synthesis of nickel(II) azacorroles by Pd-catalyzed amination of α,α'-dichlorodipyrrin Ni(II) complex and their properties.

Synthesis of nickel(II) complexes of meso-aryl-substituted azacorroles was performed by Buchwald-Hartwig amination of a dipyrrin Ni(II) complex with benzylamine through C-N and C-C coupling. The highly planar structure of Ni(II) azacorroles was elucidated by X-ray diffraction analysis. (1)H NMR analysis and nucleus independent chemical shift (NICS) calculation on Ni(II) azacorrole revealed its distinct aromaticity with [17]triaza-annulene 18π conjugation. In addition, acylation of azacorrole selectively afforded N- and C-acylated azacorroles depending on the reaction conditions, showing the dual reactivity of azacorroles.

Facile synthesis of biphenyl-fused BODIPY and its property.

A biphenyl-fused BODIPY was synthesized through a facile oxidative cyclization of peripheral aryl-substituents at the ß-position of the BODIPY unit. The extended π-system of the fused BODIPY induces near-infrared (NIR) absorption and strong π-π interactions in the solid state. These features are beneficial for the application of the dye as a functional material. The biphenyl-fused BODIPY dye was demonstrated to exhibit photocurrent conversion ability on the basis of its n-type semiconducting property.

Synthesis of directly connected BODIPY oligomers through Suzuki-Miyaura coupling.

Treatment of a meso-arylboron dipyrrin (BODIPY) with NBS provides mono- and dibrominated BODIPYs at the 2- and 6-positions in excellent yields with high regioselectivity. Brominated products can be employed as a nice building block for the synthesis of a variety of BODIPY derivatives through Suzuki-Miyaura coupling. Because of a lack of substituents at the 1,3,5,7-positions, a directly ß-ß-linked BODIPY dimer exhibits a completely coplanar conformation of BODIPY units, offering effective π-conjugation.