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Objective: To explore the accuracy and efficiency of a novel 3D-printed emulation localization model of small pulmonary nodules in lung surgery. Methods: From April 2020 to April 2021, a total of 66 patients were selected in the study, who underwent localization and resection of pulmonary nodules with video-assisted thoracoscopic surgery (VATS) guided by the 3D-printed emulation localization model at Department of Thoracic Surgery, West China Hospital of Sichuan University. There were 13 males and 53 females, aged from 25 to 79 (52.7±11.4) years. Of all patients, 24 (36.4%) had single pulmonary nodule, and 42 (63.6%) had synchronous multiple pulmonary nodules. The chest high-resolution CT image data were utilized for digital reconstruction and 3D printing to make a tailored life-size emulation pulmonary nodules localization model, which was used to navigate real-time intraoperative localization of nodules. Clinical data including operative parameters, localization information, resection types and pathological findings of nodules were analyzed. The pulmonary nodules that doctors planned to resect were categorized into two categories:major nodules and additional nodules, according to their presence of invasion and radiological risk factors. The accuracy of localization and resection efficiency of nodules were evaluated in accordance with the categories of the nodules respectively. Results: On the basis of preoperative evaluation, there were 71 major nodules with median maximal diameter of 0.9 (0.6-1.3) cm, and 77 additional nodules with median maximal diameter of 0.5 (0.4-0.7) cm. All patients underwent VATS surgery, 52 of them (78.8%) were treated with uniportal VATS and 14 (21.2%) with triportal VATS. Among the patients with single nodule, 18 segmentectomies and 6 wedge resections were performed; whereas among the patients with multiple nodules, 5 segmentectomies, 14 wedge resections, and 23 combined pulmonary resections (including 2 cases of lobectomy+segmentectomy, 7 cases of lobectomy+wedge resections, and 14 cases of segmentectomy+wedge resections) were achieved. The median operative time was 93 (45-240) min, and the median resection time for all nodules was 51.4 (6.7-147.0) min. All major nodules were successfully resected and visibly dissected after removal, and all additional nodules were successfully resected with 85.7%(66/77) nodules visibly dissected. The accuracy rate of localization of both types of nodules was 100%. All major nodules were malignant, and the malignancy rate of additional nodules was 21.2%(14/66). Conclusion: This novel 3D-printed emulation localization model of small pulmonary nodules proved to be a non-invasive, accurate and efficient technique. Not only that, it has a unique advantage in localization of synchronous multiple pulmonary nodules.

Objective: To present the surgical technique of endoscope assisted arthroplasty for total hip replacement via minimum invasive direct anterior approach and analyze its early clinical outcome. Methods: From November 2019 to May 2020, endoscopic total hip arthroplasty via direct anterior approach was performed on 30 patients (32 hips), including 12 males (13 hips) and 18 females (19hips), in the Department of Orthopedics of Fujian Provincial Hospital. The average age of patients was (63±14) years (ranged 32-87 years). The average body mass index (BMI) of the patients was (26.9±4.5) kg/m 2 . There were 12 cases whose BMI was higher than 28.0 kg/m 2 and the maximum BMI was 35.2 kg/m 2 . The surgery was performed on supine position using a 5-6 cm proximal transverse incision and a distal selective percutaneous puncture incision to perform the acetabulum preparation and the prosthesis implantation with the novel designed split tool under the monitoring of endoscope; the lift-top tractor system was used to raise the femur in the transverse incision for femoral side preparation and prosthesis implantation. Relevant data such as the perioperative status, operation time, postoperative pain score assessed with visual analogue score (VAS), prosthesis position, joint function, lateral femoral cutaneous nerve function and patient satisfaction were recorded to analyze the short-term efficacy. Results: The average length of incision of the 30 cases(32 hips)was (5.9±0.4) cm. All patients in this study had I/A wound healing with no perioperative complications such as infection, poor wound healing and fractures of the proximal femur. The average operation time was (65±14) min, and the average amount of blood loss was (136±56) ml. The average acetabular abduction angle and acetabular antegrade inclinations was 41.4°±3.6° and 16.0°±5.3°, respectively. The resting-state VAS of pain at 6 h and 24 h after operation were all ≤2, and there was no significant difference between the VAS scores after exercise and the VAS scores at the resting state (both P >0.05). There was no statistically significant difference between the VAS scores at the same state at different times (both>0.05). The weight-bearing exercise was applied in all patients within 12 h after surgery. The length of postoperative hospital stays varied from 1 to 3 days((2.0±0.9) days). At the 6th-month follow-up, the Harris score of the hip was 94.7±3.0, which significantly improved when compared with that before the operation (35.5±8.1)( P <0.01). No sensory abnormalities were observed. The satisfaction score of the patients was 9.3±0.5 (full score set to 10). Conclusions: The efficacy and safety of the endoscope assisted total hip arthroplasty for total hip replacement is acceptable. This procedure can help to reduce the compression of the muscles by the retractor in the conventional operation. It can be applied to obese and muscular patients.

Objective: To investigate appropriate protocol of treatment modulation for seasonal allergic rhinitis (AR) patients, in order to promote the implementation of personalized medicine. Methods: Total of 124 AR patients allergic to cypress pollens were recruited from January to February 2020 in Department of Allergy in Peking Union Medical College Hospital, 43 males and 81 females with an average age of (41±9) years. The patients were divided into two groups with block randomization method. In the first group, treatment was modulated every two days according to the average daily rhinoconjunctivitis symptom score of the last two days (short-term symptom-score group); while in the second group, therapy regimen was adjusted every week based on the Allergic Rhinitis Control Test (ARCT) score of the last week (long-term ARCT group). The treatment level was up-regulated when the cypress pollen count increased and stayed at a high level (step-up pharmacotherapy stage); and treatment was down-regulated while the pollen count decreased (step-down pharmacotherapy stage). Daily symptom scores, medicine scores, and ARCT scores of the two groups were recorded and compared. Results: During the whole cypress pollen season, the daily rhinoconjunctivitis symptom score of short-term symptom-score group was significantly lower than that in long-term ARCT group(2.4±1.0 vs 2.7±1.0, P <0.01), and the difference between the two groups was more pronounced in the step-up pharmacotherapy stage than that in the step-down pharmacotherapy stage, while there was no statistical difference between the daily medicine scores of the two groups ( P >0.05). During the pollen rising period, the ARCT score of short-term symptom-score group was significantly better than that of long-term ARCT group (21(19, 22) vs 20 (17, 21), P =0.049); while in the pollen peak period and decreasing period, the ARCT scores of the two groups showed no statistical difference ( P >0.05). The proportion of incompliance with doctor's advice was higher in long-term ARCT group compared to that in short-term symptom-score group (30.1% vs 6.7%, P <0.001). Conclusion: The protocol of treatment modulation for seasonal AR patients allergic to pollens should be developed flexibly according to the variation trend of pollen allergen exposure, so as to implement the idea of personalized medicine.

Objective: To set up a prediction scoring system for the hypoxemia in infants with Pierre Robin sequence after weaning and evaluate its clinical value. Methods: Data of consecutive patients from November 2016 to June 2019, who underwent mandibular distraction osteogenesis in Guangzhou Women and Children's Medical Center, were retrospectively analyzed ( n= 148). All the cases were divided into two groups according to the appearance of hypoxemia after weaning. They were randomly divided into the derivation cohorc (2/3, n= 100) and the validation cohort (1/3, n= 48). Single factor and multiple logistic regression analysis were used to select the independent risk factors related to hypoxemia and establish a prediction model. A prediction scoring system was developed in accordance with assigning of the value of each variable β in the model. Internal verification of scoring system by validation population. Data of consecutive patients from July 2019 to November 2019, who underwent mandibular distraction osteogenesis, were prospectively analyzed ( n= 26). The diagnostic accuracy were conducted to evaluate the clinical value of the scoring system. Results: The logistic regression demonstrated that age at operation, pulmonary infection and the length of distraction less than 5 mm at weaning were the independent risk factors for hypoxemia. The P value of logistic regression model in Hosmer and Lemeshow goodness of fit test was 0.848, and a prediction scoring system was established accordingly. The area under the ROC curve of the scoring system was 0.890, and the optimum critical value was 53. The sensitivity, specificity, accuracy of the model were 78.6%(11/14),86.1%(74/86), 85.0%(85/100) respectively. The predictive effectiveness of the scoring system in the retrospective validation population was similar to that in the modeling population. 26 patients were included in the prospective analysis. The area under ROC curve of the scoring system was 0.870. The sensitivity, specificity and accuracy were 80.0%(5/6),95.0%(20/21), 96.1%(25/26) respectively. Conclusion: The prediction scoring system established in the study are efficacious for the hypoxemia in infants with Pierre Robin sequence after weaning.

Objective: To explored the clinical effects of different methods of the proximal fusion for long segmental lumbar vertebrae fusion in treatment of degenerative lumbar scoliosis(DLS). Methods: From January 2007 to March 2014 fifty-five cases of DLS treated by the posterior proximal fusion of long segmental lumbar vertebrae fusion were analyzed in Department of Orthopaedics, Shanghai general Hospital of Nanjing Medical University (35)HuaiAn The First Hospital Affiliated to Nanjing Medical University(20). According to various upper instrumented vertebra(UIV) the patients were divided into Group A(upper horizontal vertebra, UHV, n =17), Group B (upper natural vertebra, UNV n =18 ), and Group C(upper end vertebra, UEV, n =20). The VAS, ODI, spinal balance parameters and postoperative complications in each group were assessed. Results: Except for 1 case death of serious lung infection in early postoperative, 54 cases were received 2-4 years follow-up. No statistical differences in improvements and fusion rates were found among 3 groups ( P >0.05). The improvements of the coronal Cobb's angle in the A group were significantly more than the C group (75.8%±12.8%, 69.6%±11.8%, 63.4%±15.3%, P <0.05). The incidences of early postoperative complications in A group were the highest, next in B group, and lowest C group (52.9%, 22.0%, 15.0%, P <0.05). The incidences of proximal ASD in the C group were significantly more than the A group (12.5%, 22.2%, 50.0%, P =0.045). Conclusion: UHV, UNV and UEV had similar clinical outcomes for treatment of degenerative lumbar scoliosis in short term. Correction of the coronal deformity of UHV was superior to UEV. UEV was beneficial to reduce early complications, but more likely to happen proximal adjacent segment degeneration in the long run.

Objective: To compare the clinical efficacies of two different procedures in the treatment of degenerative lumbar scoliosis., Methods: From August 2008 to August 2011, 28 patients of lumbar degenerative scoliosis were divided into one group (n = 14) undergoing modified transforaminal lumbar interbody fusion (TLIF) instrumented surgery and another group (n = 14) undergoing posterolateral fusion (PLF) instrumented surgery. There were 12 males and 16 females with a mean age of 66.2 years (range: 54-79). The operative durations and bleeding volumes of two groups were recorded. The post-operative efficacy was evaluated with VAS (visual analogue scale) for low back pain, ODI (Oswestry disability index), Cobb' angle and lumbar lordosis angle on plain film., Results: The mean follow-up period was 25.9 months. The operative duration was 192.0 ± 44.7 min in modified TLIF group versus 163.0 ± 39.0 min in PLF group. The bleeding volume was 718.0 ± 197.2 ml in modified TLIF group versus 546.0 ± 226.6 ml in PLF group. All operated lumbar intervertebral achieved bony fusion in modified TLIF group by the last follow-up. Two cases had no bony fusion and there was one case of pseudarthrosis in PLF group. Significant differences existed between two groups in pre-operative and post-operative values of VAS, ODI, Cobb' s angle and lumbar lordosis angle (P < 0.05). There were significant differences between two groups in the values of pre-operative and post-operative VAS and lumbar lordosis angle (P < 0.05) but not in the values of pre-operative and post-operative ODI and Cobb' s angle (P > 0.05)., Conclusion: As an alternative, safe and effective procedure, modified TLIF instrumented is superior to PLF instrumented in the treatment of lumbar degenerative scoliosis.

Objective: The study of blood flow improvement of local estrogen on the low genitourinary tract and its safety., Methods: The color Doppler flow imaging technique was employed to observe the flow spectrum of genitourinary tract. During the period of February 2007 to December 2010, there were 78 cases of postmenopausal females on local estrogen. The Doppler parameters included vaginal wall, urethra resistance index (RI) and systolic/diastolic ratio and others. And the lower genital urinary tract symptoms, such as sexual satisfaction, vulvovaginitis, urinary frequency, nocturia and other improvements, as well as adverse drug reactions before treatment and after 1 month, 3 months were recorded and analyzed., Results: The results before treatment and after 1 month, 3 months, vaginal wall artery RI were 0.9 ± 0.2, 0.6 ± 0.2 and 0.7 ± 0.3; S/D 8.6 ± 3.7, 6.0 ± 2.9 and 6.4 ± 2.1; urethral artery RI 0.7 ± 0.2, 0.6 ± 0.2 and 0.6 ± 0.2, S/D 6.6 ± 1.9, 3.5 ± 0.7 and 3.4 ± 0.5 respectively. When the pre- and post-treatment indices were compared, the differences were statistically significant (P < 0.01). After using local estrogen in postmenopausal women, the resistance of lower genital urinary tract vasodilation decreased. Sexual satisfaction increased while the morbidities of vulvovaginitis, urinary frequency and nocturia decreased. The difference was statistically significant (P < 0.01)., Conclusion: Postmenopausal females on topical estrogen may promote the blood circulation of lower genitourinary tract, red.

Objective: To explore the effect of different doses of dexmedetomidine on the sedation of recovery period and the postoperative early pain scores in pediatric patients undergoing cleft lip and palate repair., Methods: A total of 100 American Society of Anesthesiologists (ASA) I-II pediatric patients undergoing cleft lip and palate repair were randomly divided into 5 groups (D1, D2, D3, D4 and C, n = 20 each). Groups D1-D4 received a continuous pump infusion of dexmedetomidine at 0.25, 0.5, 0.75, 1.0 µg × kg(-1)× h(-1) respectively for 1 h before the completion of operation. Then an intravenous injection of 1 µg/kg was prescribed over 10 min as a loading dose. Group C, taken as control, received an equal volume of normal saline. Propofol 2 mg/kg was added for the occurrence of emergence agitation. Mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), partial pressure of end-tidal carbon dioxide (P(ET)CO(2)), Riker sedation-agitation scale, times of additional propofol requirements, times of additional artificial ventilation, extubation time, discharge time, side effects and face, legs, activity, cry and consolability (FLACC) scale were observed and recorded., Results: The Riker sedation-agitation scale were 5.3 ± 0.9, 4.3 ± 0.8, 3.5 ± 0.8, 2.6 ± 0.6 and 6.1 ± 0.7, times of additional propofol requirements were 4.7 ± 1.7, 2.5 ± 1.4, 0.8 ± 0.9, 0.1 ± 0.4 and 5.7 ± 0.7 in groups D1, D2, D3, D4 and C respectively. In short, group D4 ≈ group D3 < group D2 < group D1 < group C (P < 0.05). As compared with group D4, the extubation time and discharge time significantly increased in groups D1, D2, D3 and C (P < 0.05). The FLACC scales in groups D2, D3 and D4 were lower than those in groups D1 and C. Side effects: 2 cases developed sinus bradycardia in group D4 and heart rate returned to normal after treatment., Conclusion: At a load dosage of 1 µg/kg and a maintenance dosage of 0.75 µg × kg(-1)× h(-1), dexmedetomidine shows excellent effects on the recovery period of cleft lip and palate repairing in pediatric patients. The FLACC scale decreases with fewer side effects, but extubation time and discharge time increase.

Objective: To explore the pathogenic mechanism, operative techniques and therapeutic efficacy of lumbar degenerative scoliosis., Methods: A retrospective analysis was performed for 32 patients (14 males and 18 females with a mean age of 67.4 years old) with degenerative lumbar scoliosis undergoing posterior decompression and fusion with pedicle screw system from January 2007 to March 2010. The post-operative outcomes were radiologically evaluated with Oswestry disability index (ODI), Cobb' angle and lumbar lordosis angle., Results: All patients received a mean follow-up of 28.5 months (range: 12 - 50). All lumbar joints achieved bony fusion at Month 6 post-operation. No complications occurred due to instrumentation. There was no pseudoarthrosis. The significant differences of ODI existed between pre-operation and post-operation [(60 ± 11)% vs (21 ± 6)%, P < 0.01], Cobb' angle [(28 ± 9)° vs (13 ± 5)°, P < 0.01] and lumbar lordosis angle [(41 ± 12)° vs (20 ± 10)°, P < 0.01]., Conclusion: Individualized operations should be performed for degenerative lumbar scoliosis patients. Proper lumbar decompression and the reconstruction of coronal and sagittal balances may relieve symptoms and improve the quality of life.

Objective: To summarize the experience of hepatectomy in patients with hepatocellular carcinoma fulfilling the Milan criteria and analyze the clinicopathological factors for patient survival and tumor recurrence., Methods: The clinicopathological data of 104 patients with early-stage hepatocellular carcinoma fulfilling the Milan criteria and underwent hepatectomy at Peking Union Medical College Hospital between April 2003 and June 2009 were retrospectively analyzed., Results: The median follow-up was 24 months. There were 54 recurrent cases. The 1-, 3- and 5-year cumulative disease-free survival rate were 63.0%, 32.6% and 22.4% respectively. Neither univariate analysis nor multivariate analysis indicated any factor significantly correlated with recurrence (P>0.05). The cumulative overall survival rate at 1, 3 and 5 years were 88.8%, 68.1% and 68.1% respectively. Univariate analysis revealed that blood transfusion (P=0.000), involvement of hepatic capsule (P=0.000) and postoperative transarterial chemotherapy (P=0.049) were significantly correlated with survival. And multivariate analysis indicated that blood transfusion (P=0.001) and involvement of hepatic capsule (P=0.000) were independent prognostic factors for survival., Conclusion: For the patients with early-stage hepatocellular carcinoma and compensated liver function fulfilling the Milan criteria, hepatectomy serves as the preferred treatment strategy.

Objective: To review the clinical data of a group of patients with multi-level lumbar spine fractures treated with TSRH-3D pedicle screw system and to investigate the effect and post-operative efficacy of this technique., Methods: Eighteen patients diagnosed as multi-level lumbar spine fracture were treated with TSRH-3D pedicle screw system. The operations were performed at 4 hours to 2 days after injury and the follow-up period was 15-32 months (mean: 23 months). The X-ray and CT scan were taken both preoperatively and postoperatively., Results: (1) Twelve patients became injured from height falling (67%), 5 from traffic accident (28%) and 1 from crush (5%). (2) The improvement rate of spine motion, back pain and lower extremity pain was 67%, 94% and 78% respectively. (3) Compared with preoperative status, the height of anterior border of vertebra improved by 59.2%, lost by an average of 5.2% (P < 0.01) and the Cobb angle was corrected by 19.5 degrees , lost an average of 5.4 degrees ., Conclusion: It is feasible to treat the multi-level lumbar spine fractures with TSRH-3D pedicle screw system. And the outcome of reduction and fixation is satisfactory. This technique is excellent at improving the height of injury vertebra, physiological curvature and neural function. It also can relieve lumbocrural pain with a definite postoperative efficacy.

Objective: To explore the effects of systemic glucocorticoid treatment on tuberculous pleural effusion., Methods: Ninety Wistar rats were intrapleurally injected with 0.03 mg of standard human Mycobacterium tuberculosis to establish models of tuberculous pleural effusions and then were randomly divided into 2 equal groups both without anti-tuberculosis treatment: glucocorticoids group (GG) undergoing intramuscular injection of 0.3 mg triamcinolone acetonide in the right thigh 24 h after intrapleural injection, and control group (CG) received nothing as control. 8, 24, 32, and 48 hours, and 3, 5, 7, 10, and 15 days after intramuscular injection 5 rats from each group were killed. The thorax was opened, the amount of pleural effusion (PE) was recorded, and the pleural cavity, histopathology of pleura and lung parenchyma were examined. The white blood cell (WBC) count and differential leukocyte count, and levels of total protein (TP), glucose (GLU), and lactic dehydrogenase (LDH) in the PE were determined. Bioassays were used to detect the PE levels of soluble intercellular adhesion molecule-1 (sICAM-1), transforming growth factor beta1 (TGF-beta1), and interferon gamma (IFN-gamma)., Results: The PE volumes of GG 8 - 48 h after the intramuscular injection were significantly lower than those of CG (P < 0.05, P < 0.01), and PE completely disappeared on day 3. The WBC in PE 24 - 48 h after and the percentages of neutrophils 8 - 48 h after the intramuscular injection of GG were all significant lower than those of CG (all P < 0.01). The TP levels 32 and 48 h after the intramuscular injection of GG were both significantly higher than those of CG (both P < 0.01). The LDH level of GG within 24 h after the intramuscular injection was significantly lower than that of CG (P < 0.01). Both the sICAM-1 and TGF-beta1 levels of GG were higher 8 h after the intramuscular injection, but lower 48 h after the intramuscular injection than those of CG (both P < 0.01). The IFN-gamma levels 8 - 48 h after the intramuscular injection of GG were all higher than those of CC (all P < 0.01). The IFN-gamma/TGF-beta1 ratios at different time points of GG were all higher than those of CG, and there were significant differences in those 8 - 48 h after the intramuscular injection between these 2 groups (all P < 0.01). Pathologically, the mean thickness of pleura in GG was significantly less than that in CG. Congestion and edema in subpleural and pulmonary interstitium were less in GG than in CG., Conclusion: Early use of glucocorticoids helps reduce the inflammatory response in pleural cavity in tuberculous pleurisy accelerate the absorption of pleural effusion and decrease the thickness of pleura.

Objective: To evaluate the curative effects of transcatheter closure on perimembranous ventricular septal defects (PMVSDs) using unbalanced Amplatzer asymmetric ventricular septal defect occluder (AAVSDO)., Methods: The data of 68 patients of PMVSDs with a diameter of 6.7 mm (3 to 12 mm) and the diameter of ventricular septal rim below the aortic valve of 2.7 +/- 1.1 mm (1-5 mm), 27 males and 41 females, aged 15.6 +/- 11.5 (1.5-44), weighing 42.8 +/- 15.2 kg (10-72 kg), treated with AAVSDO, the diameter of which was 1-2 mm larger than the largest diameter of the defects determined by angled left ventriculography, from September 2002 to January 2005 were prospectively analyzed. The patients were followed up for 221 +/- 130 days (90 to 750 days)., Results: Seventy-one procedures were performed. The device was implanted successfully in 65 of the 68 patients (95.6%). The selected device diameter was 8.4 mm (4 to 14 mm). Device was lost in one patient during the procedure, which was successfully managed by recapturing the device with a snare device and redeploying it. During the procedure, transient complete left bundle branch block and right bundle branch block occurred in 6 and 5 patients respectively. On follow-up evaluation, transient junctional rhythm occurred in one patient, and accelerated ventricular rhythm in 1. After deployment of the device, the immediate complete closure rate was 43% (28/68), increased to 81.5% (53/68) on the day next to the procedure, and reached 100% 6 months after. One patient adopted surgical reparation because hemolysis occurred after the device implanted. The hospitalization time was 4.5 +/- 3.6 days (2-8 days). The X-ray exposure time was 14.8 +/- 10.7 min (6-48 min). The procedure time 72.6 +/- 38.7 min (35-186 min). One patient was diagnosed as with deep vein thrombosis because of right leg swelling at the seventh day after the procedure. The symptoms disappeared after anticoagulation treatment with low molecule weight heparin. During the scheduled long-term follow-up all patients were doing well. No episode of endocarditis, procedure-related death, or wire disruption was recorded., Conclusion: The initial and long-term follow-up results of transcatheter closure of PMVSDs are promising with high success and occlusion rates. Transcatheter closure of PMVSDs using AAVSDO appears to be the first line choice for suitable patients with such defects.

Objective: To explore the mechanism of the left cardiac sympathetic denervation (LCSD) surgery to reduce the incidence of cardiac events for long QT syndrome (LQTS) patients., Methods: 12 LQTS patients were selected to do exercise test (ET) to mimic sympathetic activation. The dynamic alterations on ECG during exercise and recovery phases (Rec) were observed and the exercise test characteristics for LQTS patients before and after surgery were summarized and compared., Results: The QTc at resting was shortened from 0.54 s +/- 0.04 s to 0.50 s +/- 0.04 s, P = 0.026, while the maximum heart rate during exercise decreased from 141 beat/min +/- 18 beat/min to 124 beat/min +/- 14 beat/min, P = 0.003. QTc was shortened during exercise, however, it was prolonged during the early recovery phase (before ET 0.54 s +/- 0.02 s, ET 10 min 0.46 s +/- 0.02 s, Rec 4 min 0.55 s +/- 0.03 s); LCSD could reduce such abrupt alteration of QTc during early recovery phase (after surgery: before ET 0.53 s +/- 0.03 s, ET 10 min 0.48 s +/- 0.03 s, Rec 4 min 0.53 s +/- 0.05 s). QT/RR interval slope, representing the adaptation response of QT interval to heart rate, became steeper after exercise (from 0.61 +/- 0.06 to 0.71 +/- 0.07 after exercise, P < 0.01). LCSD made the slopes become less steep both before exercise (from 0.61 +/- 0.06 before surgery to 0.55 +/- 0.07 after surgery, P = 0.013) and after exercise (from 0.71 +/- 0.07 before surgery to 0.66 +/- 0.06 after surgery, P = 0.018). Notched T wave alterations occurred in 7 patients at the end of exercise and/or during early recovery phase before surgery, and LCSD diminished such alteration in 4 patients., Conclusion: The slope between QT and RR both the pre-exercise and post-exercise slopes, interval becomes less steep after LCSD, which suggests that exaggerated delay in repolarization with decreasing heart rate for LQTS patients is improved by LCSD. This may be one of the mechanisms of LCSD efficacy for treating LQTS patients. Exercise test is one of tools to evaluate the effect of LCSD on LQTS patients.