Dietary Iron Restriction Protects against Aneurysm Rupture in a Mouse Model of Intracranial Aneurysm.

INTRODUCTION: Iron accumulation in vessel walls induces oxidative stress and inflammation, which can cause cerebrovascular damage, vascular wall degeneration, and intracranial aneurysmal formation, growth, and rupture. Subarachnoid hemorrhage from intracranial aneurysm rupture results in significant morbidity and mortality. This study used a mouse model of intracranial aneurysm to evaluate the effect of dietary iron restriction on aneurysm formation and rupture. METHODS: Intracranial aneurysms were induced using deoxycorticosterone acetate-salt-induced hypertension and a single injection of elastase into the cerebrospinal fluid of the basal cistern. Mice were fed an iron-restricted diet (n = 23) or a normal diet (n = 25). Aneurysm rupture was detected by neurological symptoms, while the presence of intracranial aneurysm with subarachnoid hemorrhage was confirmed by post-mortem examination. RESULTS: The aneurysmal rupture rate was significantly lower in iron-restricted diet mice (37%) compared with normal diet mice (76%; p < 0.05). Serum oxidative stress, iron accumulation, macrophage infiltration, and 8-hydroxy-2'-deoxyguanosine in the vascular wall were lower in iron-restricted diet mice (p < 0.01). The areas of iron positivity were similar to the areas of CD68 positivity and 8-hydroxy-2'-deoxyguanosine in both normal diet and iron-restricted diet mouse aneurysms. CONCLUSIONS: These findings suggest that iron is involved in intracranial aneurysm rupture via vascular inflammation and oxidative stress. Dietary iron restriction may have a promising role in preventing intracranial aneurysm rupture.

Effects of volatile anesthetics on circadian rhythm in mice: a comparative study of sevoflurane, desflurane, and isoflurane.

PURPOSE: Volatile anesthetics affect the circadian rhythm of mammals, although the effects of different types of anesthetics are unclear. Here, we anesthetized mice using several volatile anesthetics at two different times during the day. Our objective was to compare the effects of these anesthetics on circadian rhythm. METHODS: Male adult C57BL/6 J mice were divided into eight groups (n = 8 each) based on the anesthetic (sevoflurane, desflurane, isoflurane, or no anesthesia) and anesthesia time (Zeitgeber time [ZT] 6-12 or ZT18-24). Mice were anesthetized for 6 h using a 0.5 minimum alveolar concentration (MAC) dose under constant dark conditions. The difference between the start of the active phase before and after anesthesia was measured as a phase shift. Clock genes were measured by polymerase chain reaction in suprachiasmatic nucleus (SCN) samples removed from mouse brain after anesthesia (n = 8-9 each). RESULTS: Phase shift after anesthesia at ZT6-12 using sevoflurane (- 0.49 h) was smaller compared with desflurane (- 1.1 h) and isoflurane (- 1.4 h) (p < 0.05). Clock mRNA (ZT6-12, p < 0.05) and Per2 mRNA (ZT18-24, p < 0.05) expression were different between the groups after anesthesia. CONCLUSION: 0.5 MAC sevoflurane anesthesia administered during the late inactive to early active phase has less impact on the phase shift of circadian rhythm than desflurane and isoflurane. This may be due to differences in the effects of volatile anesthetics on the expression of clock genes in the SCN, the master clock of the circadian rhythm.

Association between remimazolam and postoperative delirium in older adults undergoing elective cardiovascular surgery: a prospective cohort study.

PURPOSE: Postoperative delirium is one of the most common complications after cardiovascular surgery in older adults. Benzodiazepines are a reported risk factor for delirium; however, there are no studies investigating remimazolam, a novel anesthetic agent. Therefore, we prospectively investigated the effect of remimazolam on postoperative delirium. METHODS: We included elective cardiovascular surgery patients aged ≥ 65 years at Hamamatsu University Hospital between August 2020 and February 2022. Patients who received general anesthesia with remimazolam were compared with those who received other anesthetics (control group). The primary outcome was delirium within 5 days after surgery. Secondary outcomes were delirium during intensive care unit stay and hospitalization, total duration of delirium, subsyndromal delirium, and differences in the Mini-Mental State Examination scores from preoperative to postoperative days 2 and 5. To adjust for differences in the groups' baseline covariates, we used stabilized inverse probability weighting as the primary analysis and propensity score matching as the sensitivity analysis. RESULTS: We enrolled 200 patients; 78 in the remimazolam group and 122 in the control group. After stabilized inverse probability weighting, 30.3% of the remimazolam group patients and 26.6% of the control group patients developed delirium within 5 days (risk difference, 3.8%; 95% confidence interval -11.5% to 19.1%; p = 0.63). The secondary outcomes did not differ significantly between the groups, and the sensitivity analysis results were similar to those for the primary analysis. CONCLUSION: Remimazolam was not significantly associated with postoperative delirium when compared with other anesthetic agents.

Mortality, Recurrent Thromboembolism and Major Bleeding in Cancer-Associated and Non-Cancer Pulmonary Embolism Patients Treated With Direct Oral Anticoagulants.

BACKGROUND: Pulmonary embolism (PE) is a potentially fatal form of venous thromboembolism (VTE). This study compares the mortality, incidence of recurrent VTE, and incidence of major bleeding between non-cancer and cancer-associated PE patients treated with direct oral anticoagulants (DOACs).Methods and Results:This was a retrospective, observational, single-center study involving 130 consecutive patients (87 with active cancer; 43 without cancer) who received DOAC treatment for PE between January 2016 and December 2019. Kaplan-Meier analysis showed significantly higher mortality in cancer-associated PE patients than in non-cancer patients (35/87 [40%] vs. 1/43 [2%], P<0.001, log-rank test, HR 18.6 [95% CI: 2.5-136.0]). In contrast, the cumulative incidences of recurrent VTE and major bleeding were comparable between the 2 groups. Among the cancer-associated PE patients, the incidence for the composite outcome of recurrent VTE or major bleeding was significantly higher in patients undergoing chemotherapy than in those not undergoing chemotherapy (9/37 [24%] vs. 2/50 [4%], P=0.004, log-rank test, HR 6.9 [95% CI: 1.5-32.0]). CONCLUSIONS: Although cancer-associated PE patients treated with DOACs showed higher mortality compared with non-cancer patients, presumably because of the presence of cancer, the risk of recurrent VTE or major bleeding was comparable between the 2 groups. Thus, DOAC is an important treatment option for cancer-associated PE, although underlying cancer-related risks (e.g., chemotherapy) remain.

Genetic diversity of enterovirus G detected in faecal samples of wild boars in Japan: identification of novel genotypes carrying a papain-like cysteine protease sequence.

The genetic diversity of enterovirus G (EV-G) was investigated in the wild-boar population in Japan. EV-G-specific reverse transcription PCR demonstrated 30 (37.5 %) positives out of 80 faecal samples. Of these, viral protein 1 (VP1) fragments of 20 samples were classified into G1 (3 samples), G4 (1 sample), G6 (2 samples), G8 (4 samples), G11 (1 sample), G12 (7 samples), G14 (1 sample) and G17 (1 sample), among which 11 samples had a papain-like cysteine protease (PL-CP) sequence, believed to be the first discoveries in G1 (2 samples) or G17 (1 sample) wild-boar EV-Gs, and in G8 (2 samples) or G12 (6 samples) EV-Gs from any animals. Sequences of the non-structural protein regions were similar among EV-Gs possessing the PL-CP sequence (PL-CP EV-Gs) regardless of genotype or origin, suggesting the existence of a common ancestor for these strains. Interestingly, for the two G8 and two G12 samples, the genome sequences contained two versions, with or without the PL-CP sequence, together with the homologous 2C/PL-CP and PL-CP/3A junction sequences, which may explain how the recombination and deletion of the PL-CP sequences occured in the PL-CP EV-G genomes. These findings shed light on the genetic plasticity and evolution of EV-G.

Multiple genotypes of enterovirus G carrying a papain-like cysteine protease (PL-CP) sequence circulating on two pig farms in Japan: first identification of enterovirus G10 carrying a PL-CP sequence.

Two and three genotypes of enterovirus G (EV-G) carrying a papain-like cysteine protease (PL-CP) sequence were detected on two pig farms and classified into genotypes G1 and G10, and G1, G8, and G17, respectively, based on VP1 sequences. A G10 EV-G virus bearing a PL-CP sequence was detected for the first time. Phylogenetic analysis of the P2 and P3 regions grouped the viruses by farm with high sequence similarity. Furthermore, clear recombination break points were detected in the 2A region, suggesting that PL-CP EV-G-containing strains gained sequence diversity through recombination events among the multiple circulating EV-G genotypes on the farms.

Complete genome sequencing and genetic analysis of a Japanese porcine torovirus strain detected in swine feces.

We sequenced the complete genome of a porcine torovirus (PToV) strain from Japan for the first time. Whole-genome analysis revealed that this strain (Iba/2018) has a mosaic sequence composed of at least three genome backgrounds, related to US, Chinese and German PToV strains. Clear recombination breakpoints were detected in the M and HE coding regions. A similarity plot and structural analysis demonstrated that the HE coding region exhibits the highest diversity, and the most sequence variation was found in the lectin domain. PToVs were divided into two lineages in the HE region, whereas clear lineages were not found in other regions.

Single-center prognostic validation of the risk assessment of the 2015 ESC/ERS guidelines in patients with pulmonary arterial hypertension in Japan.

The 2015 European Society of Cardiology/European Respiratory Society guidelines for the diagnosis and treatment of pulmonary hypertension include a multidimensional risk assessment for patients with pulmonary arterial hypertension (PAH). However, prognostic validations of this risk assessment are limited, especially outside Europe. Here, we validated the risk assessment strategy in PAH patients in our institution in Japan. Eighty consecutive PAH patients who underwent right heart catheterization between November 2006 and December 2018 were analyzed. Patients were classified as low, intermediate, or high risk by using a simplified version of the risk assessment that included seven variables: World Health Organization functional class, 6-min walking distance, peak oxygen consumption, brain natriuretic peptide, right atrial pressure, mixed venous oxygen saturation, and cardiac index. The high-risk group showed significantly higher mortality than the low- or intermediate-risk group at baseline (P < 0.001 for both comparisons), and the mortalities in the intermediate- and low-risk groups were both low (P = 0.989). At follow-up, patients who improved to or maintained a low-risk status showed better survival than those who did not (P = 0.041). Our data suggest that this risk assessment can predict higher mortality risk and long-term survival in PAH patients in Japan.

Safety and Efficacy of Long-Term Use of Tolvaptan in Patients With Heart Failure and Chronic Kidney Disease.

BACKGROUND: We assessed the long-term safety and efficacy of tolvaptan in 102 patients with heart failure (HF) and chronic kidney disease (CKD). Median follow-up duration was 1.6 years (1.0-4.4 years).Methods and Results:One patient discontinued tolvaptan because of hypernatremia. There were no changes in renal function or electrolytes during the 1-year follow-up. The cardiac-related death-free or HF-related hospitalization-free survival rate was significantly higher in patients receiving tolvaptan than in propensity score-matched patients who did not receive tolvaptan. CONCLUSIONS: In patients with HF and CKD, long-term administration of tolvaptan was well-tolerated, relatively safe and effective, suggesting its utility for long-term management of these conditions.

Activation of PPARγ at an Early Stage of Differentiation Enhances Adipocyte Differentiation of MEFs Derived from Type II Diabetic TSOD Mice and Alters Lipid Droplet Morphology.

Type 2 diabetic Tsumura, Suzuki, obese, diabetes (TSOD) mice gradually gain weight as compared to corresponding Tsumura, Suzuki, non-obesity (TSNO) control mice, and develop insulin resistance. Although development of type 2 diabetes mellitus is associated with dysfunction of adipocytes, little is known about the properties of adipocytes from TSOD mice. Therefore, we attempted to remove intracorporeal factors and elucidate inherent properties of adipocytes of TSOD mice using adipocytes differentiated from mouse embryonic fibroblasts (MEFs) in vitro. Here, we show that MEFs of TSOD have low potency for differentiation into adipocytes. The percentage of Oil red O-stained cells and levels of adipogenic markers in cells differentiated from MEFs of TSOD are lower than those in cells differentiated from MEFs of TSNO. We further show that treatment with an agonist of peroxisome proliferator-activated receptor-γ (PPARγ) (rosiglitazone) at an early stage of differentiation increases the percentage of Oil red O-stained cells in TSOD-MEFs differentiated into adipocytes. Moreover, the lipid droplet size in those adipocytes is larger than that in the adipocytes differentiated from MEFs of TSNO. Although persistent treatment of MEFs of TSOD with rosiglitazone during differentiation increases the percentage of Oil red O-stained cells, the lipid droplet size in adipocytes treated as such does not reach the size of those treated in early stage only. Thus, activation of PPARγ by its agonist at an early stage of differentiation compensates for the low potency toward adipogenic differentiation of, and accelerates formation of enlarged lipid droplets in adipocytes derived from, MEFs of TSOD mice.

Lipoprotein(a) levels predict adverse vascular events after acute myocardial infarction.

Lipoprotein(a) [Lp(a)], which is genetically determined, has been reported as an independent risk factor for atherosclerotic vascular disease. However, the prognostic value of Lp(a) for secondary vascular events in patients after coronary artery disease has not been fully elucidated. This 3-year observational study included a total of 176 patients with ST-elevated myocardial infarction (STEMI), whose Lp(a) levels were measured within 24 h after primary percutaneous coronary intervention. We divided enrolled patients into two groups according to Lp(a) level and investigated the association between Lp(a) and the incidence of major adverse cardiac and cerebrovascular events (MACCE). A Kaplan-Meier analysis demonstrated that patients with higher Lp(a) levels had a higher incidence of MACCE than those with lower Lp(a) levels (log-rank P = 0.034). A multivariate Cox regression analysis revealed that Lp(a) levels were independently correlated with the occurrence of MACCE after adjusting for other classical risk factors of atherosclerotic vascular diseases (hazard ratio 1.030, 95 % confidence interval: 1.011-1.048, P = 0.002). In receiver-operating curve analysis, the cutoff value to maximize the predictive power of Lp(a) was 19.0 mg/dl (area under the curve = 0.674, sensitivity 69.2 %, specificity 62.0 %). Evaluation of Lp(a) in addition to the established coronary risk factors improved their predictive value for the occurrence of MACCE. In conclusion, Lp(a) levels at admission independently predict secondary vascular events in patients with STEMI. Lp(a) might provide useful information for the development of secondary prevention strategies in patients with myocardial infarction.

Clinical benefit of tolvaptan in patients with acute decompensated heart failure and chronic kidney disease.

Tolvaptan, a vasopressin type 2 receptor antagonist, has an aquaretic effect without affecting renal function. The effects of long-term tolvaptan administration in heart failure patients with renal dysfunction have not been clarified. Here, we assessed the clinical benefit of tolvaptan during a 6-month follow-up in acute decompensated heart failure (ADHF) patients with severe chronic kidney disease (CKD; estimated glomerular filtration rate (eGFR) <45 mL/min/1.73 m(2)). We compared 33 patients with ADHF and severe CKD who were administered tolvaptan in addition to loop diuretics (TLV group), with 36 patients with ADHF and severe CKD who were administered high-dose loop diuretics (≥40 mg) alone (LD group). Alterations in serum creatinine and eGFR levels from the time of hospital discharge to 6-month follow-up were significantly different between the groups, with those in the TLV group being more favorable. Furthermore, Kaplan-Meier analysis revealed that rehospitalization for heart failure (HF) was significantly lower in the TLV group compared with the LD group. In ADHF patients with severe CKD, tolvaptan use for 6 months reduced worsening of renal function and rehospitalization rates for HF when compared with conventional diuretic therapy. In conclusion, tolvaptan could be a safe and effective agent for long-term management of HF and CKD.

Generation of broadband terahertz vortex beams.

We propose and demonstrate a method for generating broadband terahertz (THz) vortex beams. We convert a THz radially polarized beam into a THz vortex beam via achromatic polarization optical elements for THz waves and characterize the topological charge of the generated vortex beam by measuring the spatial distribution of the phase of the THz wave at its focal plane. For example, a uniform topological charge of +1 is achieved over a wide frequency range. We also demonstrate that the sign of the topological charge can be easily controlled. By utilizing the orbital angular momentum of the beam, these results open new THz wave technologies for sensing, manipulation, and telecommunication.

Split-based elevational localization of photoacoustic guidewire tip by 1D array probe using spatial impulse response.

Objective. Photoacoustic emitters on the tip of a therapeutic device have been intensively studied for echo-guided intervention purposes. In this study, a novel method for localizing the guidewire tip emitter in the elevation direction using a 1D array probe is proposed to resolve the issue of the tip potentially deviating from the ultrasound-imaged plane.Approach. Our method uses the 'interference split' that appears when the emitter is off-plane. Here, a point source from the emitter splits into two points in images. Based on the split, 'split-based elevation localization (SEL)' is introduced to estimate the absolute elevation position of the emitter. Additionally, 'Signed SEL' incorporates an asymmetric feature into the 1D probe to obtain the sign of the elevation localization. An attenuative coupler is attached to the half side of the probe to control the interference split. In SEL and Signed SEL, we propose a modeled split matching (MSM) algorithm to localize the tip position. MSM performs pattern matching of a measured split waveform with modeled split waveforms corresponding to all emitter positions in a region of interest. The modeled waveforms are precalculated using the spatial impulse response. The proposed method is numerically and experimentally validated.Main results. Numerical simulations for time-domain wave propagation clearly demonstrated the interference split phenomena. In the experimental validation with a vessel-mimicking phantom, the proposed methods successfully estimated the elevation positions,yb.SEL exhibited a root-mean-squared error (RMSE) of 2.0 mm for the range of 0 mm ≤yb≤ 30 mm, while Signed SEL estimated the absolute position with an RMSE of 2.4 mm and the sign with an accuracy of 80.8% for the range of -30 mm ≤yb≤ 30 mm.Significance.These results suggest that the proposed method could provide approximate tip positions and help sonographers track it by fanning the probe.

Clinical usefulness of endothelial progenitor cells in predicting the efficacy of riociguat in chronic thromboembolic pulmonary hypertension.

Endothelial dysfunction is important in the pathology of pulmonary hypertension, and circulating endothelial progenitor cells (EPCs) have been studied to evaluate endothelial dysfunction. In patients with chronic thromboembolic pulmonary hypertension (CTEPH), riociguat reportedly increases the number of circulating EPCs. However, the relationship between EPC numbers at baseline and changes in clinical parameters after riociguat administration has not been fully elucidated. Here, we evaluated 27 treatment-naïve patients with CTEPH and analyzed the relationships between EPC number at diagnosis and clinical variables (age, hemodynamics, atrial blood gas parameters, brain natriuretic peptide, and exercise tolerance) before and after riociguat initiation. EPCs were defined as CD45dim CD34+ CD133+ cells and measured by flow cytometry. A low number of circulating EPCs at diagnosis was significantly correlated with increased reductions in mean pulmonary arterial pressure (mPAP) (correlation coefficient = 0.535, P = 0.004) and right atrial pressure (correlation coefficient = 0.618, P = 0.001) upon riociguat treatment. We then divided the study population into two groups according to the mPAP change: a weak-response group (a decrease in mPAP of 4 mmHg or less) and a strong-response group (a decrease in mPAP of more than 4 mmHg). The number of EPCs at diagnosis was significantly lower in the strong-response group than in the weak-response group (P = 0.022), but there were no significant differences in other clinical variables or in medication profiles. In conclusion, circulating EPC numbers could be a potential predictor of the therapeutic effect of riociguat in CTEPH patients.

Tarsal tunnel syndrome in hemodialysis patients: a case series.

BACKGROUND: The purpose of our study was to investigate tarsal tunnel syndrome (TTS) arising in patients who have undergone maintenance dialysis at our facility and to evaluate the frequency, pathological characteristics, and diagnosis of TTS. METHODS: We evaluated 1011 patients (mean age 65.1 years) undergoing maintenance dialysis from 2000 to 2006 at our hospital. In patients diagnosed with TTS, we examined clinical symptoms and imaging findings. In addition, we evaluated intraoperative findings in patients who had undergone surgery. A follow-up study was conducted for at least 1 year. RESULTS: Five patients (7 ankles) (mean age 57.8 years) were diagnosed as have TTS, with a mean dialysis duration of 23.4 years (range, 7-30 years). With conservative treatment consisting of rest and a steroid injection, 4 ankles showed improvement. Surgery was performed on 3 ankles. Amyloidoma, nodular tumor fragile deposits in the soft tissue or thecal surface, proliferation of the synovial tendon sheath, and thickened joint capsule were recognized in 3 ankles, and a concomitant ganglion was recognized in 1 ankle. Histologically, the deposition of hyaline material was recognized in all tissues, including the walls of the ganglion or joint capsule, by staining to a pale red color using Congo red stain. An immunohistochemical study indicated positive staining by ß-2 microglobulin staining. The flexor retinaculum was thin in all cases, with retinaculum-like thickness not found in carpal tunnel syndrome. CONCLUSIONS: We believe that the occurrence of TTS in dialysis patients was 0.5%, with a tendency to be more prevalent among patients undergoing maintenance dialysis for 5 or more years. The pathological process of TTS may be different from that of carpal tunnel syndrome. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Novel recombinant porcine enterovirus G viruses lacking structural proteins are maintained in pig farms in Japan.

Type 1 recombinant enterovirus G (EV-G), which carries the papain-like cysteine protease (PLCP) gene of torovirus between its 2C/3A regions, and type 2 recombinant EV-G, which carries the torovirus PLCP gene with its flanking regions having non-EV-G sequences in place of the viral structural genes, have been detected in pig farms in several countries. In a previous study, we collected 222 fecal samples from 77 pig farms from 2104 to 2016 and detected one type 2 recombinant EV-G genome by metagenomics sequencing. In this study, we reanalyzed the metagenomic data and detected 11 type 2 recombinant EV-G genomes. In addition, we discovered new type 2 recombinant EV-G genomes of the two strains from two pig farms samples in 2018 and 2019. Thus, we identified the genomes of 13 novel type 2 recombinant EV-Gs isolated from several pig farms in Japan. Type 2 recombinant EV-G has previously been detected only in neonatal piglets. The present findings suggest that type 2 recombinant EV-G replicates in weaning piglets and sows. The detection of type 1 recombinant EV-Gs and type 2 recombinant EV-Gs at 3-year and 2-year intervals, respectively, from the same pig farm suggests that the viruses were persistently infecting or circulating in these farms.

Terahertz vector beam generation using segmented nonlinear optical crystals with threefold rotational symmetry.

We propose and demonstrate a simple method for cylindrical vector beam generation in the terahertz frequency region using optical rectification in segmented nonlinear crystals with threefold rotational symmetry. We used segmented GaP(111) plates to generate the terahertz cylindrical vector beam, and obtained clear evidence of the beam generation with a terahertz camera. By this method, a broadband terahertz cylindrical vector beam can be generated, and the radial and azimuth modes can be easily switched. We also report on the direct observation of the longitudinal electric field components at the focal point using a terahertz time-domain spectroscopy technique.

Label-free enzymatic reaction monitoring in water-in-oil microdroplets using ultra-broadband multiplex coherent anti-Stokes Raman scattering spectroscopy.

We propose a system for monitoring an enzymatic reaction, i.e., dehydrogenation of ethanol catalyzed by alcohol dehydrogenase, in microdroplets using ultra-broadband multiplex coherent anti-Stokes Raman scattering (CARS) spectroscopy. The reaction solution was encapsulated in water-in-oil microdroplets with diameters of 50 µm. The reaction was monitored by measuring the concentration of coenzymes from the CARS spectrum obtained in one-second exposure time. The results obtained using our system was consistent with those of the conventional fluorescence measurement system and indicate the potential of CARS spectroscopy for droplet-based high-throughput screening of enzymes.

Usefulness of a refined computed tomography imaging method to assess the prevalence of residual pulmonary thrombi in patients 1 year after acute pulmonary embolism: The Nagoya PE study.

BACKGROUND: Post-pulmonary embolism (PE) syndrome is an important clinical condition that can affect the long-term prognosis after acute PE. OBJECTIVE: We aimed to evaluate the prevalence of residual pulmonary thrombi and the thrombotic burden 1 year after acute PE, by using our refined computed tomography (CT) imaging method. PATIENTS/METHODS: In this prospective study, patients diagnosed with acute PE were recruited and examinations were conducted at 1 month, 6 months, and 1 year. Especially at 1 year, patients were evaluated multifacetedly, including by laboratory tests, quality-of-life, 6-min walking test, and enhanced CT. RESULTS: Fifty-two patients were enrolled. Two patients (3.8%) developed chronic thromboembolic pulmonary hypertension. A total of 43 patients completed evaluation at 1 year, among whom (74%) had residual thrombi, with a median modified CT obstruction index (mCTOI) of 10.7%. In multivariate analysis, residual thrombi at 1 month was the only factor significantly related to residual thrombi at 1 year (odds ratio, 103.4; 95% confidence interval, 4.2-2542.1). The tricuspid regurgitation pressure gradient ≥60 mmHg and left ventricular end-diastolic dimension at diagnosis were significantly related to mCTOI at 1 year (ß = 0.367, P = .003; and ß = -0.435, P = .001, respectively). CONCLUSIONS: Using our improved CT imaging protocol, we found a high prevalence of residual thrombi 1 year after acute PE. Furthermore, right ventricular overload was related to the thrombotic burden. The long-term treatment strategy of acute PE could be modified to include precise CT imaging.