Objective: To examine the clinical efficacy of myectomy guided by personalized three-dimensional reconstruction and printing for patients with obstructive hypertrophic cardiomyopathy. Methods: The clinical data of 28 patients with obstructive hypertrophic cardiomyopathy, who underwent septal myectomy guided by personalized three-dimensional reconstruction and printing in the Department of Cardiaovascular Surgery, Guangdong Provincial People's Hospital from May 2020 to December 2021, were retrospectively analyzed. There were 14 males and 14 females, aging (51.1±14.0) years (range: 18 to 72 years). Enhanced cardiac computed tomography images were imported into Mimics software for preoperative three-dimensional reconstruction. The direction of the short axial plane of each segment was marked perpendicularly to the interventricular septum on the long axial plane of the digital cardiac model, then the thickness was measured on each short axial plane. A figurative digital model was used to determine the extent of resection and to visualize mitral valve and papillary muscle abnormalities. Correlation between the length, width, thickness, and volume of the predicted resected myocardium and those of the surgically resected myocardium was assessed by Pearson correlation analysis or Spearman correlation analysis. The accuracy of detecting mitral valve and papillary muscle abnormalities of transthoracic echocardiography and three-dimensional reconstruction was also compared. Results: There was no death or serious complications like permanent pacemaker implantation, re-sternotomy for bleeding, low cardiac output syndrome, stroke, or multiple organ dysfunction syndromes in the whole group. Namely, the obstruction of the left ventricular outflow tract was effectively relieved. The systolic anterior motion of the anterior mitral valve leaflet was absent in all patients after myectomy. The length, width, and thickness of the predicted resected myocardium by three-dimensional reconstruction were significantly positively correlated with the length (R=0.65, 95%CI: 0.37 to 0.82, P<0.01), width (R=0.39, 95%CI: 0.02 to 0.67, P<0.01), and thickness (R=0.82, 95%CI: 0.65 to 0.92, P<0.01) of the surgically resected myocardium, while the relation of the volume of the predicted resected myocardium and the volume of the surgically resected myocardium was a strong positive correlation (R=0.88, 95%CI: 0.76 to 0.94, P<0.01). Importantly, the interventricular septal myocardial thickness measured by preoperative transthoracic echocardiography showed a moderate positive correlation with the volume of surgically resected myocardium (R=0.52, 95%CI: 0.19 to 0.75, P<0.01). During a follow-up of (14.4±6.8) months (range: 3 to 22 months), no death occurred, and 1 patient was readmitted for endocardial radiofrequency ablation due to atrial fibrillation. Conclusion: Personalized three-dimensional reconstruction and printing can not only visualize the intracardiac structure but also guide septal myectomy by predicting the thickness, volume, and extent of resected myocardium to achieve ideal resection.
Female ; Humans ; Male ; Cardiomyopathy, Hypertrophic/diagnosis* ; Imaging, Three-Dimensional ; Printing, Three-Dimensional ; Retrospective Studies ; Treatment Outcome ; Ventricular Septum ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged

Septal reduction therapies, which include septal myectomy and alcohol septal ablation and so on, are the current treatment strategies for patients with obstructive hypertrophic cardiomyopathy and drug-refractory symptoms. With the deepening of theoretical understanding and the rapid development of interventional therapies, some researchers have tried to perform transcatheter mitral valve edge-to-edge repair to treat high-risk patients with hypertrophic cardiomyopathy, including obstructive and non-obstructive. The reported results are relatively satisfactory, but many urgent problems need to be solved, such as the lack of data on animal experiments and large cohort studies, and the unknown medium- and long-term outcomes. However, transcatheter mitral valve edge-to-edge repair brings new ideas for the diagnosis and treatment of patients with hypertrophic cardiomyopathy. On one hand, it can be used as a monotherapy, on the other hand, it can be combined with novel molecular targeted drug therapy or emerging minimally invasive surgical procedures targeting hypertrophic ventricular septum, which deserves our further attention and exploratory research.
Humans ; Treatment Outcome ; Cardiomyopathy, Hypertrophic/surgery* ; Mitral Valve/surgery* ; Ventricular Septum/surgery* ; Hypertrophy

Objectives: To examine the short-term and mid-term effects of surgical treatment of obstructive hypertrophic cardiomyopathy (HCM) in one center. Methods: The perioperative data and short-term follow-up outcomes of 421 patients with obstructive HCM who received surgical treatment at Department of Cardiac Surgery, Zhongshan Hospital, Fudan University from January 2017 to December 2021 were analyzed retrospectively. There were 207 males and 214 females, aged (56.5±11.7) years (range: 19 to 78 years). Preoperative New York Heart Association (NYHA) classification included 45 cases of class Ⅱ, 328 cases in class Ⅲ, and 48 cases in class Ⅳ. Fifty-eight patients were diagnosed with latent obstructive HCM and 257 patients had moderate or more mitral regurgitation with 56 patients suffering from intrinsic mitral valve diseases. All procedures were completed by a multidisciplinary team, including professional echocardiologists involving in preoperative planning for proper mitral valve management strategies and intraoperative monitoring. A total of 338 patients underwent septal myectomy alone, and 59 patients underwent mitral valve surgery along with myectomy. A single transaortic approach was used in 355 patients, and a right atrial-atrial septal/atrial sulcus approach was used in 51 other patients. Long-handled minimally invasive surgical instruments were used for the procedures. Student t test, Wilcoxon rank sum test, χ² test or Fisher exact test were used to compare the data before and after surgery. Results: The aortic cross-clamping time of septal myectomy alone was (34.3±8.5) minutes (range: 21 to 94 minutes). Eighteen patients had intraoperative adverse events and underwent immediate reoperation, including residual obstruction (10 patients), left ventricular free wall rupture (4 patients), ventricular septal perforation (3 patients), and aortic valve perforation (1 patient). Four patients died during hospitalization, and 11 patients developed complete atrioventricular block requiring permanent pacemaker implantation. After discharge, 384 (92.1%) patients received a follow-up visit with a median duration of 9 months. All follow-up patients survived with significantly improved NYHA classifications: 216 patients in class Ⅰ and 168 patients in class Ⅱ (χ²=662.73, P<0.01 as compared to baseline). At 6 months after surgery, follow-up echocardiography showed that the thickness of the ventricular septum ((13.6±2.5) mm vs. (18.2±3.0) mm, t=23.51, P<0.01) and the peak left ventricular outflow tract gradient ((12.0±6.3) mmHg vs. (93.4±19.8) mmHg, 1 mmHg=0.133 kPa, t=78.29, P<0.01) were both significantly lower than baseline values. Conclusion: The construction of the surgical team (including echocardiography experts), proper mitral valve management strategies, identification and management of sub-mitral-valve abnormalities, and application of long-handled minimally invasive surgical instruments are important for the successful implementation of septal myectomy with satisfactory short-and medium-term outcomes.
Male ; Female ; Humans ; Retrospective Studies ; Atrial Fibrillation ; Treatment Outcome ; Cardiomyopathy, Hypertrophic/surgery* ; Mitral Valve Insufficiency/surgery* ; Ventricular Septum

Objective: To examine the short-term curative effect with minimally invasive right infra-axillary thoracotomy for transaortic modified Morrow procedure. Methods: The clinical data of 60 patients who underwent video-assisted thoracoscopic transaortic modified Morrow procedure from August 2021 to August 2022 at Department of Cardiovascular Surgery, Zhejiang Provincial People's Hospital were retrospectively analyzed. There were 31 males and 29 females, with the age (M (IQR)) of 54.0(22.3) years (range: 15 to 71 years). The echocardiography confirmed the diagnosis of moderate mitral regurgitation in 30 patients, and severe mitral regurgitation in 13 patients. Systolic anterior motion (SAM) was present preoperatively in 54 patients. All 60 patients underwent transaortic modified Morrow procedure through a right infra-axillary thoracotomy using femorofemoral cardiopulmonary bypass. Surgical procedures mainly included transverse aortic incision, exposure of left ventricular outflow tract (LVOT), septal myectomy, and correction of the abnormal mitral valve and subvalvular structures. Results: All 60 patients underwent the programmatic procedures successfully without conversion to full sternotomy. The cardiopulmonary bypass time was (142.0±32.1) minutes (range: 89 to 240 minutes), while the cross-clamp time was (95.0±23.5) minutes (range: 50 to 162 minutes). The patients had a postoperative peak LVOT gradient of 7.0 (5.0) mmHg (range: 0 to 38 mmHg) (1 mmHg=0.133 kPa). A total of 57 patients were extubated on the operating table. The drainage volume in the first 24 h was (175.9±57.0) ml (range: 60 to 327 ml). The length of intensive care unit stay was 21.0 (5.8)h (range: 8 to 120 h) and postoperative hospital stay was 8 (5) days (range: 5 to 19 days). The postoperative septal thickness was 11 (2) mm (range: 8 to 14 mm). All patients had no iatrogenic ventricular septal perforation or postoperative residual SAM. The patients were followed up for 4 (9) months (range: 1 to 15 months), and none of them needed cardiac surgery again due to valve dysfunction or increased peak LVOT gradient during follow-up. Conclusion: Using a video-assisted thoracoscopic transaortic modified Morrow procedure through a right infra-axillary minithoracotomy can provide good visualization of the LVOT and hypertrophic ventricular septum, ensure optimal exposure of the mitral valve in the presence of complex mitral subvalvular structures, so that allows satisfactory short-term surgical results.
Male ; Female ; Humans ; Mitral Valve Insufficiency/surgery* ; Thoracotomy ; Retrospective Studies ; Cardiomyopathy, Hypertrophic/surgery* ; Ventricular Septum/surgery* ; Treatment Outcome ; Minimally Invasive Surgical Procedures/methods*

Objective: To examine the early effect of thoracoscopic trans-mitral myectomy for hypertrophic cardiomyopathy patients with left midventricular obstruction. Methods: From April 2020 to July 2021, 10 hypertrophic cardiomyopathy patients with left midventricular obstruction underwent thoracoscopic trans-mitral myectomy at Guangdong Provincial People's Hospital. The whole group of patients consisted of 7 males and 3 females aged (52.0±16.4) years (range: 18 to 68 years). The EuroSCORE Ⅱ predicted mortality rate was 1.78% (1.20%) (M(IQR)) (range: 0.96% to 4.86%). The clinical data were collected and analyzed retrospectively to evaluate the clinical efficacy by comparing preoperative and postoperative echocardiographic parameters using paired t-test, paired Wilcoxon test or Fisher exact test, including left ventricular outflow tract peak pressure gradient, maximum interventricular septum thickness, systolic anterior motion of the anterior mitral leaflet and so on. The safety was determined by summarizing the incidence of perioperative and follow-up complications. Results: All the procedures successed with no conversion to median sternotomy, septal defect, ventricular rupture. There was no in-hospital 30-day death, neither serious complications like permanent pacemaker implantation, re-sternotomy for bleeding, low cardiac output syndrome, stroke, or multiple organ dysfunction syndrome. The left ventricular outflow tract obstruction was effectively relieved in all patients expect a patient developed residual obstruction. Compared with that of pre-operation, the thickness of the interventricular septum was significantly reduced from (22.1±4.0) mm to (10.3±1.7) mm (t=10.693, P<0.01), while the left ventricular outflow tract peak pressure gradient was significantly reduced from (81.7±21.1) mmHg to 12.3 (11.5) mmHg (Z=-2.805, P<0.01) (1 mmHg=0.133 kPa). Conclusion: Thoracoscopic trans-mitral myectomy is an effective and safe procedure for hypertrophic cardiomyopathy patients with left midventricular obstruction.
Male ; Female ; Humans ; Retrospective Studies ; Echocardiography ; Treatment Outcome ; Cardiomyopathy, Hypertrophic/complications* ; Ventricular Septum

Objective: Explore the relationship between tip of the left bundle branch pacing lead and anatomic location of left bundle branch as well as the mechanism of left bundle branch current of injury. To clarify the clinical value of left bundle branch current of injury during operation. Methods: The pacing leads were implanted in the hearts of two living swines. Intraoperative electrophysiological study confirmed that the left bundle branch or only the deep left ventricular septum was captured at low output. Immediately after operation, the gross specimen of swine hearts was stained with iodine to observe the gross distribution of His-purkinje conduction system on the left ventricular endocardium and its relationship with the leads. Subsequently, the swine hearts were fixed with formalin solution, and the pacing leads were removed after the positions were marked. The swine hearts were then sectioned and stained with Masson and Goldner trichrome, and the relationship between the anatomic location of the conduction system and the tip of the lead was observed under a light microscope. Results: After iodine staining of the specimen, the His-purkinje conduction system was observed with the naked eye in a net-like distribution, and the lead tip was screwed deeply and fixed in the left bundle branch area of the left ventricular subendocardium in the ventricular septum. Masson and Goldner trichrome staining showed that left bundle branch pacing lead directly passed through the left bundle branch when there was left bundle branch potential with left bundle branch current of injury, while it was not directly contact the left bundle branch when there was left bundle branch potential without left bundle branch current of injury. Conclusion: The left bundle branch current of injury observed on intracardiac electrocardiogram during His-purkinje conduction system pacing suggests that the pacing lead directly contacted the conduction bundle or its branches, therefore, the captured threshold was relatively low. Left bundle branch current of injury can be used as an important anatomic and electrophysiological evidence of left bundle branch capture.
Animals ; Swine ; Bundle of His/physiology* ; Ventricular Septum ; Cardiac Pacing, Artificial ; Heart Conduction System ; Electrocardiography ; Iodine

Objective: Explore the relationship between tip of the left bundle branch pacing lead and anatomic location of left bundle branch as well as the mechanism of left bundle branch current of injury. To clarify the clinical value of left bundle branch current of injury during operation. Methods: The pacing leads were implanted in the hearts of two living swines. Intraoperative electrophysiological study confirmed that the left bundle branch or only the deep left ventricular septum was captured at low output. Immediately after operation, the gross specimen of swine hearts was stained with iodine to observe the gross distribution of His-purkinje conduction system on the left ventricular endocardium and its relationship with the leads. Subsequently, the swine hearts were fixed with formalin solution, and the pacing leads were removed after the positions were marked. The swine hearts were then sectioned and stained with Masson and Goldner trichrome, and the relationship between the anatomic location of the conduction system and the tip of the lead was observed under a light microscope. Results: After iodine staining of the specimen, the His-purkinje conduction system was observed with the naked eye in a net-like distribution, and the lead tip was screwed deeply and fixed in the left bundle branch area of the left ventricular subendocardium in the ventricular septum. Masson and Goldner trichrome staining showed that left bundle branch pacing lead directly passed through the left bundle branch when there was left bundle branch potential with left bundle branch current of injury, while it was not directly contact the left bundle branch when there was left bundle branch potential without left bundle branch current of injury. Conclusion: The left bundle branch current of injury observed on intracardiac electrocardiogram during His-purkinje conduction system pacing suggests that the pacing lead directly contacted the conduction bundle or its branches, therefore, the captured threshold was relatively low. Left bundle branch current of injury can be used as an important anatomic and electrophysiological evidence of left bundle branch capture.
Animals ; Swine ; Bundle of His/physiology* ; Ventricular Septum ; Cardiac Pacing, Artificial ; Heart Conduction System ; Electrocardiography ; Iodine

Objective: To explore the safety and feasibility of stereotactic radiation therapy (SBRT) strategy for irradiating porcine ventricular septum, see if can provide a preliminary experimental evidence for clinical SBRT in patients with hypertrophic obstructive cardiomyopathy (HOCM). Methods: Five male pigs (39-49 kg, 6 months old) were used in this study. Pigs were irradiated at doses of 25 Gy (n=2) or 40 Gy (n=3). Delineation of the target volume was achieved under the guidance of 3-dimensional CT image reconstruction, and SBRT was then performed on defined target volume of porcine ventricular septum. Blood biomarkers, electrocardiogram and echocardiography parameters were monitored before and after SBRT. Pathological examination (HE staining, Masson staining) was performed on the target and non-target myocardium at 6 months post SBRT. Results: SBRT was successful and all animals survived to the designed study endpoint (6 months) after SBRT. Serum cardiac troponin T (cTnT) level was significantly higher than the baseline level at 1 day post SBRT, and reduced at 1 week after SBRT, but was still higher than the baseline level(P<0.05). Serum N-terminal pro-B type natriuretic peptide (NT-proBNP) was also significantly increased at 1 day post SBRT (P<0.05) and returned to baseline level at 1 week post SBRT. The serum NT-proBNP level was (249±78), (594±37) and (234±46) pg/ml, respectively, and the cTnT was (14±7), (240±40) and (46±34) pg/ml, respectively at baseline, 1 day and 1 week after SBRT in the 40 Gy dose group. The serum NT-proBNP level was (184±20), (451±49) and (209±36) pg/ml, respectively, the cTnT values ​​were (9±1), (176±29) and (89±27) pg/ml, respectively at baseline, 1 day and 1 week after SBRT in the 25 Gy dose group. Both NT-proBNP and cTnT values tended to be higher post SBRT in the 40 Gy dose group as compared with the 25 Gy dose group, but the difference was not statistically significant (P>0.05). The left ventricular ejection fraction and the left ventricular end-diastolic diameter remained unchanged before and after SBRT (P>0.05). The interventricular septum thickness showed a decreasing trend at 6 months after SBRT, but the difference was not statistically significant ((9.54±0.24) mm vs. (9.82±8.00) mm, P>0.05). The flow velocity of the left ventricular outflow tract, and the valve function and morphology were not affected by SBRT. At 6 months after SBRT, HE staining revealed necrosis in the irradiated target area of ​​the myocardium in the 40 Gy dose group and the 25 Gy dose group, and the degree of necrosis in the irradiated interventricular septum was more obvious in the 40 Gy dose group as compared with the 25 Gy group. The combined histological analysis of the two groups showed that the necrotic area of ​​the irradiated target area accounted for (26±9)% of the entire interventricular septum area, which was higher than that of the non-irradiated area (0) (P<0.05). There was no damage or necrosis of myocardial tissue outside the target irradiation area in both groups. The results of Masson staining showed that the percentage area of myocardial fibrosis was significantly higher in the irradiated target area than non-irradiated area ((12.6±5.3)% vs. (2.5±0.8)%, P<0.05). Conclusion: SBRT is safe and feasible for irradiating porcine ventricular septum.
Animals ; Feasibility Studies ; Male ; Necrosis ; Radiosurgery/methods* ; Stroke Volume ; Swine ; Ventricular Function, Left ; Ventricular Septum

OBJECTIVES: To compare the left ventricular systolic function between the 1eft bundle branch pacing (LBBP) and right ventricular septum pacing (RVSP) in patients with pacemaker dependence by three-dimensional speckle tracking imaging (3D-STI). METHODS: A total of 65 patients with atrioventricular block (AVB) (Mobitz type II second-degree AVB, high-degree AVB, or third-degree AVB), who underwent permanent cardiac pacing implantation including 32 patients receiving LBBP (LBBP group) and 33 patients receiving RVSP (RVSP group) from June 2018 to June 2019,were enrolled in this study. These patients met the following inclusion criterion: pre-operative left ventricular ejection fraction (LVEF)>50% and ventricular pacing rate>40% at 6-month programming follow-up; and the patients underwent echocardiography at pre-operation and 6 months after operation. The 3D-STI was used to obtain global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and global area strain (GAS). RESULTS: All the patients in the LBBP group and the RVSP group had normal LVEF, there was no significant difference between the 2 group ( CONCLUSIONS For patients with pacemaker dependence and normal LVEF at pre-operation, the cardiac function in the LBBP group is not significantly better than that in the RVSP group in short term follow-up. But in terms of physiologic pacing and long-term cardiac function protection, the 1eft bundle branch pacing is an optimal pacing mode.
Bundle of His ; Cardiac Pacing, Artificial ; Humans ; Pacemaker, Artificial ; Stroke Volume ; Ventricular Function, Left ; Ventricular Septum/diagnostic imaging*

Objectives: To explore the impact of strength sport on heart structure by echocardiography (ECHO) and cardiac resonance imaging (CMR). Methods: This is a case control study. A total of 14 male weightlifter athletes who underwent physical examination in Peking University Third Hospital from January 16, 2019 to November 1, 2019 were included in this study. Fourteen age-matched healthy Chinese men served as the control group. ECHO and CMR were used to detect the heart structure and function of the participants. Results: The age of athlete group was (21±3) years, and the training time was (9±4) years. The weekly exercise time of athlete group was more than 15 hours, while that of control group was less than 3 hours. ECHO-derived interventricular septal (IVS) thickness value ((9.3±1.3) mm vs. (8.1±0.5) mm, P=0.006) and CMR-derived IVS value ((11.0±1.5) mm vs. (10.0±0.5) mm, P=0.003) was both significantly higher in the athlete group than in the control group. For the athlete group, the indicators of left ventricular volume measured by ECHO (left ventricular end diastolic volume (LVEDV), left ventricular end diastolic volume index (LVEDVI), left ventricular end systolic volume, left ventricular end systolic volume index) and IVS thickness were significantly lower than those measured by CMR (all P<0.05). Left ventricular ejection fraction ((67.0±3.8)% vs. (59.0±3.9)%, P<0.001) and left ventricular global longitudinal strain ((19.3±2.9)% vs. (11.2±1.2)%, P<0.001) values measured by ECHO were significantly higher than those measured by CMR. There was no significant difference in the proportion of subjects with the left ventricular end diastolic diameter, LVEDV and LVEDVI above the upper limit of normal as measured by ECHOs and CMR (all P>0.05). IVS values measured by ECHO were all within the normal range, and CMR showed that 9 (9/14) weightlifter athletes had IVS>11 mm with a maximum thickness of 13.8 mm, which occurred in the inferoseptum. Conclusion: Weightlifter sport could result in thickening of the left ventricular inferoseptum, and CMR is superior to ECHO in detecting the thickening of the left ventricular wall, which serves as a helpful tool for sports medicine supervision.
Adolescent ; Adult ; Athletes ; Case-Control Studies ; China ; Echocardiography ; Humans ; Magnetic Resonance Imaging ; Male ; Stroke Volume ; Ventricular Function, Left ; Ventricular Septum ; Young Adult