Preclose Versus Postclose Using Suture-Mediated Vascular Closure System for Catheter Ablation With Femoral Vein Access.

BACKGROUND: Differences in the efficacy and safety between the preclose and postclose suture-mediated vascular closure systems for femoral vein access have not been adequately studied. OBJECTIVES: This study aimed to evaluate the efficacy and safety of these 2 suturing techniques in femoral vein access. METHODS: Patients subjected to elective catheter ablation via the femoral vein using a sheath of 8- to 13-F inner diameter (n = 282) were randomized to the preclose or postclose groups for the single-suture technique using ProGlide/ProStyle (Abbott Vascular). Duplex ultrasound was performed on days 1 and 90 after the procedure to evaluate vascular complications. The primary efficacy endpoint was rebleeding requiring recompression, and the primary safety endpoint was any major complication occurring within 90 days. The secondary efficacy endpoints included time to hemostasis and time to ambulation, and the secondary safety endpoint was any minor complication occurring within 90 days. RESULTS: The preclose group demonstrated a significantly lower rebleeding rate (5 of 141 [3.5%] vs 15 of 141 [10.6%]; P = 0.03) and shorter time to hemostasis (254.0 ± 120.4 seconds vs 299.8 ± 208.2 seconds; P = 0.02) compared with the postclose group. Five patients in each group were lost to follow-up at 90 days. Incidence of major complications were similar in both groups (1 of 136 [0.7%]; P = 1.00), whereas minor complications were observed in 18 of 136 (13.2%) and 21 of 136 (15.4%) patients in the preclose and postclose groups, respectively, without a significant difference (P = 0.73). CONCLUSIONS: In femoral vein access using the single-suture technique with ProGlide/ProStyle, the preclose technique presented a higher hemostasis rate than the postclose technique, without compromising safety.

Detection of Epicardial Connection Through Intercaval Bundle Involving Right Pulmonary Veins After Ipsilateral Circumferential Ablation by Intra-Atrial Activation Sequence Pacing From the Right Pulmonary Vein.

BACKGROUND: An epicardial connection (EC) through the intercaval bundle (EC-ICB) between the right pulmonary vein (RPV) and right atrium (RA) is one of the reasons for the need for carina ablation for PV isolation and may reduce the acute and chronic success of PV isolation. We evaluated the intra-atrial activation sequence during RPV pacing after failure of ipsilateral RPV isolation and sought to identify specific conduction patterns in the presence of EC-ICB. METHODS AND RESULTS: This study included 223 consecutive patients who underwent initial catheter ablation of atrial fibrillation. If the RPV was not isolated using circumferential ablation or reconnected during the waiting period, an exit map was created during mid-RPV carina pacing. If the earliest site on the exit map was the RA, the patient was classified into the EC-ICB group. The exit map, intra-atrial activation sequence, and RPV-high RA time were evaluated. First-pass isolation of the RPV was not achieved in 36 patients (16.1%), and 22 patients (9.9%) showed reconnection. Twelve and 28 patients were classified into the EC-ICB and non-EC-ICB groups, respectively, after excluding those with multiple ablation lesion sets or incomplete mapping. The intra-atrial activation sequence showed different patterns between the 2 groups. The RPV-high RA time was significantly shorter in the EC-ICB than in the non-EC-ICB group (69.2±15.2 versus 148.6±51.2 ms; P<0.001), and RPV-high RA time<89.0 ms was highly predictive of the existence of an EC-ICB (sensitivity, 91.7%; specificity, 89.3%). CONCLUSIONS: An EC-ICB can be effectively detected by intra-atrial sequencing during RPV pacing, and an RPV-high RA time of <89.0 ms was highly predictive.

Configuration of the neoaortic root after chimney reconstruction in the Norwood procedure.

OBJECTIVES: After staged reconstruction for hypoplastic left heart syndrome, the neoaortic root tends to dilate, and the incidence of significant neoaortic valve insufficiency increases with time. This study aimed to evaluate the mid-term outcomes of the neoaortic root geometries and valve function after chimney reconstruction in the Norwood procedure. METHODS: Between 2013 and 2021, 20 consecutive patients who underwent chimney reconstruction during the Norwood procedure for hypoplastic left heart syndrome and its variants in our institution were enrolled. The actual diameters of the following points were measured, and Z-scores were calculated based on the normal aortic root geometries using the long axis view of echocardiography at the pre-Norwood stage and the lateral view of angiography at pre-Glenn, pre-Fontan, post-Fontan and follow-up (age 5-6 years) stages: neoaortic valve annulus; sinus of Valsalva; sinotubular junction; and ascending aorta just proximal to the anastomosis to the aortic arch. The degree of neoaortic valve regurgitation was evaluated by echocardiography at each stage. RESULTS: The median follow-up period was 3.9 years. Neoaortic roots after chimney reconstruction were spared from progressive dilation over time. With growth, the conical configuration of the neoaortic roots was preserved without geometrical distortion. The Z-scores of the annulus, sinus of Valsalva, sinotubular junction and ascending aorta ranged roughly from 4 to 6, 4 to 6, 2 to 4 and 0 to 2, respectively. All neoaortic valves at each stage had mild or no regurgitation. CONCLUSIONS: Chimney reconstruction prevented neoaortic root dilation and avoided significant neoaortic valve regurgitation in the mid-term. These neoaortic dimensions with smooth flow profiles in the neoaorta after chimney reconstruction may have contributed to the current results. Further studies are needed to clarify the long-term outcomes.

Efficacy of High-Density Three-Dimensional Mapping for Verapamil-Sensitive Left Posterior Fascicular Ventricular Tachycardia in Pediatric Patients.

In verapamil-sensitive left posterior fascicular ventricular tachycardia (LPF-VT), radiofrequency catheter ablation (RFA) is performed targeting mid-to-late diastolic potential (P1) and presystolic potential (P2) during tachycardia. This study included four patients who had undergone electrophysiological study (EPS) and pediatric patients with verapamil-sensitive LPF-VT who had undergone RFA using high-density three-dimensional (3D) mapping. The included patients were 11-14 years old. During EPS, right bundle branch block and superior configuration VT were induced in all patients. VT mapping was performed via the transseptal approach. P1 and P2 during VT were recorded in three of the four patients. All patients initially underwent RFA via the transseptal approach. In three patients, P1 during VT was targeted, and VT was terminated. The lesion size indices in which VT was terminated were 4.6, 4.6, and 4.7. For one patient whose P1 could not be recorded, linear ablation was performed perpendicularly in the area where P2 was recorded during VT. Among the three patients in whom VT was terminated, linear ablation was performed in two to eliminate the ventricular echo beats. In all patients, VT became uninducible in the acute phase and had not recurred 8-24 months after RFA. High-density 3D mapping with an HD Grid Mapping Catheter allows recording of P1 and P2 during VT and may improve the success rate of RFA in pediatric patients with verapamil-sensitive LPF-VT.

Genetic and chemical targeting of the ATPase complex TIP48 and 49 impairs acute myeloid leukemia.

The chromatin-associated AAA+ ATPases Tip48 and Tip49 are the core components of various complexes implicated in diverse nuclear events such as DNA repair and gene regulation. Although they are frequently overexpressed in many human cancers, their functional significance remains unclear. Here, we show that loss of Tip49 triggered p53-dependent apoptosis and inhibited leukemia development in vivo. To examine the impact of chemical inhibition of this complex on leukemia, we have developed the novel compound DS-4950, which interferes with the ATPase activity of the Tip48/49. Administration of DS-4950 was well-tolerated in healthy mice, and the drug effectively reduced tumor burden and improved survival. We also provide evidence that the dependency on Tip48/49 is widely conserved in non-hematologic malignancies with wild type p53. These results demonstrated that the Tip48/49 ATPases are functionally necessary and therapeutically targetable for the treatment of human cancers.

Calmodulinopathy in Japanese Children　- Their Cardiac Phenotypes Are Severe and Show Early Onset in Fetal Life and Infancy.

BACKGROUND: Cardiac calmodulinopathy, characterized by a life-threatening arrhythmia and sudden death in the young, is extremely rare and caused by genes encoding calmodulin, namely calmodulin 1 (CALM1), CALM2, and CALM3.Methods and Results: We screened 195 symptomatic children (age 0-12 years) who were suspected of inherited arrhythmias for 48 candidate genes, using a next-generation sequencer. Ten probands were identified as carrying variants in any of CALM1-3 (5%; median age 5 years), who were initially diagnosed with long QT syndrome (LQTS; n=5), catecholaminergic polymorphic ventricular tachycardia (CPVT; n=3), and overlap syndrome (n=2). Two probands harbored a CALM1 variant and 8 probands harbored 6 CALM2 variants. There were 4 clinical phenotypes: (1) documented lethal arrhythmic events (LAEs): 4 carriers of N98S in CALM1 or CALM2; (2) suspected LAEs: CALM2 p.D96G and D132G carriers experienced syncope and transient cardiopulmonary arrest under emotional stimulation; (3) critical cardiac complication: CALM2 p.D96V and p.E141K carriers showed severe cardiac dysfunction with QTc prolongation; and (4) neurological and developmental disorders: 2 carriers of CALM2 p.E46K showed cardiac phenotypes of CPVT. Beta-blocker therapy was effective in all cases except cardiac dysfunction, especially in combination with flecainide (CPVT-like phenotype) and mexiletine (LQTS-like). CONCLUSIONS: Calmodulinopathy patients presented severe cardiac features, and their onset of LAEs was earlier in life, requiring diagnosis and treatment at the earliest age possible.

Clinical significance of serum cytokine profiles for differentiating between Kawasaki disease and its mimickers.

OBJECTIVES: To investigate the clinical significance of serum cytokine profiles for differentiating between Kawasaki disease (KD) and its mimickers. METHODS: Patients with KD, including complete KD, KD shock syndrome (KDSS), and KD with macrophage activation syndrome (KD-MAS), and its mimickers, including multisystem inflammatory syndrome in children, toxic shock syndrome, and Yersinia pseudotuberculosis infection, were enrolled. Serum levels of interleukin (IL)-6, soluble tumor necrosis factor receptor type II (sTNF-RII), IL-10, IL-18, and chemokine (C-X-C motif) ligand 9 (CXCL9) were measured using enzyme-linked immunosorbent assay and compared them with clinical manifestations. RESULTS: Serum IL-6, sTNF-RII, and IL-10 levels were significantly elevated in patients with KDSS. Serum IL-18 levels were substantially elevated in patients with KD-MAS. Patients with KD-MAS and KD mimickers had significantly elevated serum CXCL9 levels compared with those with complete KD. Area under the receiver operating characteristic curve analysis showed that serum IL-6 was the most useful for differentiating KDSS from the others, IL-18 and CXCL9 for KD-MAS from complete KD, and CXCL9 for KD mimickers from complete KD and KD-MAS. CONCLUSION: Serum cytokine profiles may be useful for differentiating between KD and its mimickers.

A new predictor of the optimal pulmonary artery reconstruction method during the arterial switch operation.

OBJECTIVES: The aim of this study was to more accurately predict the optimal pulmonary artery (PA) reconstruction procedure (Lecompte manoeuvre or original Jatene procedure) during the arterial switch operation, we focused on the horizontal sectioning (HS) angle between the left hilum PA and the great arteries using preoperative computed tomography imaging. METHODS: We defined the HS angle α (ß) as the angle between the tangential line from the posterior (anterior) wall of the left PA at the hilum to the left anterior (right posterior) surface of the main PA and the tangential line from the left surface of the ascending aorta to the left anterior (right posterior) surface of the main PA. We identified 14 consecutive patients diagnosed with transposition of the great arteries or transposition of the great artery-type double-outlet right ventricle who underwent preoperative computed tomography imaging. The original Jatene or Lecompte procedure was used for 9 (OJ group) and 5 (L group) patients. Relationships of the great arteries of the OJ and L groups were side by side in 8 and 2 patients, oblique in 1 and 1 patient and anteroposterior in 0 and 2 patients, respectively. RESULTS: In the OJ group, ß was greater than α in all patients. The median α/ß value was 0.618. In group L, α was greater than ß in all patients. The median α/ß was 1.307. Left PA stenosis caused by stretching was not observed in the L group. Coronary obstruction was not identified in the OJ group. Left PA stenosis behind the neo-ascending aorta was observed in 1 patient in the OJ group and required reoperation. CONCLUSIONS: The HS angle may be a useful predictor of optimal intraoperative PA reconstruction during arterial switch operation, especially for side-by-side or oblique relationships.

Drug-Facilitated Crystallization of Spray-Dried CD-MOFs with Tunable Morphology, Porosity, And Dissolution Profile.

Metal-organic frameworks (MOFs) with versatile functionalities have applications in environmental science, sensor separation, catalysis, and drug delivery. In particular, MOFs used in drug delivery should be biodegradable and easy to control. In this study, spray-dried cyclodextrin-based MOFs (CD-MOFs) with tunable crystallinity, porosity, and dissolution properties were fabricated. The spray-drying precursor properties, such as ethanol volume ratio, incubation time, and precursor concentration, were optimized for controlled crystallization. On the basis of the morphology, X-ray diffraction peak intensity, and specific surface areas of the spray-dried CD-MOF products, they were categorized as amorphous, partially crystalline, and highly crystalline. An active pharmaceutical ingredient ketoconazole (KCZ) was introduced into the precursor to prepare KCZ-containing CD-MOFs. The surface areas of these products were greater by 3-fold (292 m2/g) than that of the plain CD-MOF (94.1 m2/g) prepared using the same parameters. The presence of KCZ in the hydrophobic cavity between the two γ-CD molecules was correlated to the CD-MOF crystal growth. Additionally, CD-MOF particles exhibited different dissolution behaviors on the basis of the position of KCZ in the MOF. These spray-dried CD-MOFs with tunable morphology, specific surface area, and dissolution could have potential applications in various fields.

Prediction of atrioventricular conduction disturbance after ablation of persistent atrial fibrillation.

The prevalence of atrioventricular conduction disturbance (AVCD) in patients with persistent atrial fibrillation (AF) has not yet been fully investigated. We sought to identify the predictors of AVCD in patients with AF by analyzing the relationship between pre-ablation heart rate during AF and the PR interval in sinus rhythm after ablation. We analyzed pre-ablation 24-h Holter electrocardiogram (ECG) and 12 lead ECG 12 months after ablation of 121 consecutive patients with persistent AF who underwent their first ablation procedure and maintained sinus rhythm at 12 months. AVCD was defined as a first-degree atrioventricular block (AVB), second-degree AVB, high-degree AVB, or third-degree AVB observed on ECG at 12 months after ablation. Seventeen out of 121 patients (14.0%) had AVCD at 12 months. In the group with AVCD, total heartbeat (THB) and maximum heart rate (Max HR) were significantly lower, and the prevalence of concomitant Cavo-tricuspid isthmus-dependent atrial flutter before ablation and the appearance of macro reentrant atrial tachycardia (AT) during the procedure were significantly higher than those in the group without AVCD. Multiple regression analysis revealed that maximum HR and macro reentrant AT were significant predictors of AVCD. Receiver operating characteristic curve analysis revealed that Max HR of <165.0 bpm predicts AVCD with a sensitivity of 76.47% and a specificity of 74.00%. In patients with persistent AF, low Max HR and the presence of macro reentrant AT during the ablation procedure were predictors of AVCD.

Ablation index-guided high-power vs. moderate-power cavotricuspid isthmus ablation.

Ablation index (AI)-guided ablation is useful for pulmonary vein isolation (PVI) and cavotricuspid isthmus (CTI) ablation. However, the impact of radiofrequency (RF) application power on CTI ablation with a fixed target AI remains unclear. One-hundred-thirty drug-refractory atrial fibrillation and/or atrial flutter patients who underwent AI-guided CTI ablation with or without PVI between July 2020 and August 2021 were randomly assigned to high-power (45 W) and moderate-power (35 W) groups. We performed CTI ablation with the same target AI value in both groups: 500 for the anterior 1/3 segments and 450 for the posterior 2/3 segments. In total, first-pass conduction block of the CTI was obtained in 111 patients (85.4%), with 7 patients (5.4%) showing CTI reconnection. The rate of first-pass conduction block was significantly higher in the 45 W group (61/65, 93.8%) than in the 35 W group (50/65, 76.9%, P = 0.01). CTI ablation and CTI fluoroscopy time were significantly shorter in the 45 W group than in the 35 W group (CTI ablation time: 192.3 ± 84.8 vs. 319.8 ± 171.4 s, P < 0.0001; CTI fluoroscopy time: 125.2 ± 122.4 vs. 171.2 ± 124.0 s, P = 0.039). Although there was no significant difference, steam pops were identified in two patients from the 45 W group at the anterior segment of the CTI. The 45 W ablation strategy was faster and provided a higher probability of first-pass conduction block than the 35 W ablation strategy for CTI ablation with a fixed AI target.

Sternocleidomastoid Muscle Thickness Correlates with Exercise Tolerance in Patients with COPD.

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) have difficulties inhaling as the diaphragm becomes flattened and weakened due to lung hyperinflation. This weakened respiratory function is compensated for by the increased activity of the accessory respiratory muscles, such as the sternocleidomastoid muscle (SCM). OBJECTIVES: This study aimed to evaluate the difference in the SCM thickening fraction (SCM TF) of each respiratory phase (end-expiration, resting inspiration, and end-inspiration), as measured using ultrasonography (US), between patients with COPD and control subjects. We also evaluate the correlation between the SCM TF of each respiratory phase and exercise tolerance in patients with COPD. METHODS: Patients with COPD (n = 44) and age-matched controls (n = 20) underwent US for determination of the SCM TF. Ventilation parameters, including the peak oxygen uptake (peak VO2) and the change in the inspiratory capacity, were measured during cardiopulmonary exercise testing. The SCM thickness and TF was measured during end-expiration, resting breathing, and end-inspiration. RESULTS: The SCM was significantly thinner in patients with COPD than in controls at end-expiration. The increase in the SCM TF from end-expiration to end-inspiration in patients with COPD did not differ significantly from that in control subjects. In contrast, the SCM TF from end-expiration to resting inspiration was significantly greater in patients with COPD than in control subjects. The peak VO2 was strongly positively correlated with the SCM TF from end-expiration to end-inspiration in patients with COPD (r = 0.71, p < 0.01). CONCLUSIONS: The SCM may be thinner in patients with COPD than in controls. The SCM TF may also be associated with exercise tolerance.

One-year-old boy with refractory Listeria monocytogenes meningitis due to persistent hypercytokinemia.

We had a case of Listeria monocytogenes (LM) meningitis complicated with hypercytokinemia and hemophagocytic lymphohistiocytosis in a healthy 22-month-old boy. He was admitted to our hospital with a fever, vomiting, mild consciousness disturbances, and extraocular muscle paralysis. Magnetic resonance imaging (MRI) revealed bilateral deep white matter lesions. After receiving ampicillin, meropenem, and gentamicin, his cerebrospinal fluid (CSF) culture results turned negative on the third day of hospitalization. However, the fever intermittently persisted, and it took approximately 40 days to completely resolve. During this period, various inflammatory cytokine levels, particularly neopterin, in the blood and CSF remained elevated. Therefore, long-term administration of corticosteroids in addition to antibiotics was required. The use of dexamethasone appeared to be effective for neurological disorders such as consciousness disturbance and extraocular muscle paralysis associated with abnormal brain MRI findings. LM meningitis may present with encephalopathy and persistent fever due to hypercytokinemia. In such cases, corticosteroid therapy should be considered.

Ultra-high-density three-dimensional mapping system and radiofrequency catheter ablation for intra-atrial reentrant tachycardia in a patient with atriopulmonary connection Fontan.

A 33-year-old man, who had undergone atriopulmonary connection Fontan procedure (AP Fontan) for double outlet right ventricle, suffered from heart failure due to atrial tachycardia at 27 years old. Atrial tachycardia was suppressed after amiodarone administration. At 32 years old, atrial tachycardia recurred, and short palpitations gradually increased. Cardiac computed tomography showed that coronary sinus (CS) was perfused into the pulmonary venous atrium, and catheter insertion to CS from the systemic venous atrium was impossible. We performed an electrophysiology study (EPS) and radiofrequency catheter ablation (RFCA) under local anesthesia. An esophageal electrode catheter was inserted as a potential reference for ultra-high density three-dimensional (3D) mapping system. Two types of atrial tachycardia were induced by EPS. Ultra-high-density 3D mapping system revealed an intra-atrial reentrant pattern around the scar area on the lower right atrium in both atrial tachycardias; therefore, we diagnosed intra-atrial reentrant tachycardia (IART). The low voltage area and inferior vena cava during IART were ablated linearly, and IART was terminated.In conclusion, a CS electrode catheter cannot be inserted in a patient with AP Fontan, and ultra-high-density 3D mapping using the esophageal electrode catheter as a potential reference enables accurate and rapid mapping and is very effective for RFCA. Learning objective: The incidence of intra-atrial reentrant tachycardia (IART) is high in patients with late after Fontan procedure, and the treatment may be difficult. Ultra-high-density three-dimensional mapping can perform accurate mapping of IART and rapid detection of low voltage areas effective for radiofrequency catheter ablation. An esophageal electrode catheter can be the reference potential for accurate activation mapping in Fontan patients where coronary sinus electrode catheter insertion may be impossible from a systemic venous atrium.

The efficacy of pacemaker implantation for extracardiac total cavopulmonary connection in a pediatric patient with bradycardia-tachycardia syndrome.

A 9-year-old boy, diagnosed with double outlet right ventricle after birth, suffered sinus node dysfunction and non-sustained junctional tachycardia after an extracardiac total cavopulmonary connection (TCPC). Spontaneous atrial tachycardia appeared 3 years after an extracardiac TCPC. Sotalol was administered but the bradycardia was obvious. It was difficult to increase sotalol and atrial tachycardia was uncontrollable. Atrial tachycardia continued with symptoms; direct current (DC) cardioversion was frequently required. Five years after extracardiac TCPC, we implanted a pacemaker with atrial antitachycardia pacing (ATP) using epicardial leads. On day 2 post operation, wide QRS tachycardia appeared. Due to decreased blood pressure, DC cardioversion was immediately performed, but it recurred from atrial premature contraction. We judged this was atrial tachycardia with 1:1 atrioventricular conduction based on an intracardiac electrogram and it was terminated by burst atrial pacing from the pacemaker. After changing atrial pacing rate to 150 ppm, atrial tachycardia could be suppressed. Due to atrial pacing and increasing sotalol gradually, junctional tachycardia terminated spontaneously, and atrial tachycardia was not induced after pacemaker implantation. In conclusion, implantation of a pacemaker with ATP and intensification of antiarrhythmic drugs is an effective treatment strategy for pediatric patients with bradycardia-tachycardia syndrome after extracardiac TCPC. .

Expanded Polytetrafluoroethylene Conduits With Bulging Sinuses and a Fan-Shaped Valve in Right Ventricular Outflow Tract Reconstruction.

We developed a handmade expanded polytetrafluoroethylene (ePTFE) pulmonary valvular conduit (PVC) with bulging sinuses and a fan-shaped ePTFE valve for right ventricular outflow tract (RVOT) reconstruction. We aimed to investigate the results of this device in this multicenter study. From 2001 to 2020, 1776 patients underwent RVOT reconstruction using ePTFE PVCs at 65 institutions in Japan. The median age and body weight were 4.1 years (range, 3 days to 67.1 years) and 13.3 (range, 1.8-91.3) kg, respectively. The median PVC size was 18 (range, 8-24) mm. The median Z-value of the ePTFE PVC was 1.1 (range, -3.8 to 5.0). The ePTFE PVC conditions were investigated by cardiac echocardiography and catheterization. The median follow-up period was 3.3 years (range, 0 day to 16.2 years). There were only 9 cases (0.5%) with PVC-related unknown deaths. Reintervention was performed in 283 patients (15.9%), and 190 patients (10.7%) required explantation. Freedom from reintervention and explantation at 5/10 years were 86.7/61.5% and 93.0/69.1%, respectively. At the latest echocardiography, PVC regurgitation grade was better than mild in 88.4% patients. The average peak RVOT gradient was 15.7 ± 15.9 mm Hg at the latest cardiac catheterization. ePTFE PVC infection was detected in only 8 patients (0.5%). Relative stenosis due to somatic growth was the most common cause of PVC explantation. The performance of ePTFE in terms of durability, valvular performance, and the resistance against infection is considerable and may replace conventional prosthetic materials. Further improvement of the ePTFE membrane is essential to prevent valvular dysfunction.

Diaphragmatic excursion is correlated with the improvement in exercise tolerance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease.

BACKGROUND: In patients with chronic obstructive pulmonary disease (COPD), the maximum level of diaphragm excursion (DEmax) is correlated with dynamic lung hyperinflation and exercise tolerance. This study aimed to elucidate the utility of DEmax to predict the improvement in exercise tolerance after pulmonary rehabilitation (PR) in patients with COPD. METHODS: This was a prospective cohort study. Of the 62 patients with stable COPD who participated in the outpatient PR programme from April 2018 to February 2021, 50 completed the programme. Six-minute walk distance (6MWD) was performed to evaluate exercise tolerance, and ultrasonography was performed to measure DEmax. Responders to PR in exercise capacity were defined as patients who demonstrated an increase of > 30 m in 6MWD. The receiver operating characteristic (ROC) curve was used to determine the cut-off point of DEmax to predict responses to PR. RESULTS: Baseline levels of forced expiratory volume in 1 s, 6MWD, maximum inspiratory pressure, DEmax and quadriceps muscle strength were significantly higher, and peak dyspnoea of modified Borg (mBorg) scale score was lower in responders (n = 30) than in non-responders (n = 20) to PR (p < 0.01). In multivariate analysis, DEmax was significantly correlated with an increase of > 30 m in 6MWD. The area under the ROC curve of DEmax to predict responders was 0.915, with a sensitivity and specificity of 83% and 95%, respectively, at a cut-off value of 44.9 mm of DEmax. CONCLUSION: DEmax could adequately predict the improvement in exercise tolerance after PR in patients with COPD.

Ascending aortic extension to enlarge the retroaortic space in children after the Norwood procedure.

Left pulmonary artery stenosis is a well-recognized complication following the Norwood procedure. We herein report two cases in which ascending aortic extension was performed to enlarge the retroaortic space in children with left pulmonary artery stenosis after the Norwood procedure. We used graft interposition in the ascending aorta to increase the retroaortic apace and concomitantly performed extended left pulmonary artery reconstruction. This procedure obtains a more balanced distribution of the pulmonary blood flow, which is crucial to achieve good Fontan circulation.