Thoracic and cardiovascular surgeries in Japan during 2019

Committee for Scientific Affairs, The Japanese Association for Thoracic Surgery · Kenji Minatoya · Yukio Sato · Yasushi Toh · Tomonobu Abe · Shunsuke Endo · Yasutaka Hirata · Michiko Ishida · Hisashi Iwata · Takashi Kamei · Nobuyoshi Kawaharada · Shunsuke Kawamoto · Kohji Kohno · Hiraku Kumamaru · Goro Matsumiya · Noboru Motomura · Rie Nakahara · Morihito Okada · Hisashi Saji · Aya Saito · Hideyuki Shimizu · Kenji Suzuki · Hirofumi Takemura · Tsuyoshi Taketani · Hiroya Takeuchi · Wataru Tatsuishi · Hiroyuki Yamamoto · Takushi Yasuda · Masayuki Watanabe · Naoki Yoshimura · Masanori Tsuchida · Yoshiki Sawa

Since 1986, the Japanese Association for Thoracic Surgery has conducted annual thoracic surgery surveys throughout Japan to determine statistics on the number of procedures performed by surgical categories.Herein, we summarize the results of the association's annual thoracic surgery surveys in 2019.We regret that, for various reasons, this report has been delayed to 2023.
Adhering to the norm thus far, thoracic surgery had been classified into three categories, including cardiovascular, general thoracic, and esophageal surgeries, with patient data for each group being examined and analyzed.We honor and value all members' continued professional support and contributions.
Incidence of hospital mortality was included in the survey to determine nationwide status, which has contributed to Japanese surgeons' understanding of the present status of thoracic surgery in Japan while helping in surgical outcome improvements by enabling comparisons between their work and that of others.This approach has enabled the association to gain a better understanding of present problems and prospects, which is reflected in its activities and member education.
The 30-day mortality (also known as operative mortality) is defined as death within 30 days of surgery, regardless of the patient's geographic location, including post-discharge from the hospital.Hospital mortality is defined as death within any time interval following surgery among patients yet to be discharged from the hospital.
Transfer to a nursing home or a rehabilitation unit is considered hospital discharge unless the patient subsequently dies of complications from surgery, while hospitalto-hospital transfer during esophageal surgery is not considered a form of discharge.In contrast, hospital-to-hospital transfer 30 days following cardiovascular and general thoracic surgeries are considered discharge given that National Clinical Database (NCD)-related data were used in these categories.

Survey abstract
All data on cardiovascular, general thoracic, and esophageal surgeries were obtained from the NCD.In 2018, the data collection method for general thoracic and esophageal surgeries had been modified from self-reports using questionnaire sheets following each institution belonging to the Japanese Association for Thoracic Surgery to an automatic package downloaded from the NCD in Japan.
The data collection related to cardiovascular surgery (initially self-reported using questionnaire sheets in each participating institution up to 2014) changed to downloading an automatic package from the Japanese Cardiovascular Surgery Database (JCVSD), which is a cardiovascular subsection of the NCD in 2015.

Final report: 2019 (A) Cardiovascular surgery
We are extremely pleased with the cooperation of our colleagues (members) in completing the cardiovascular surgery survey, which has undoubtedly improved the quality of this annual report.We are truly grateful for the significant efforts made by all participants within each participating institution in completing the JCVSD/NCD.
Figure 1 illustrates the development of cardiovascular surgery in Japan over the past 33 years.Aneurysm surgery includes only surgeries for thoracic and thoracoabdominal aortic aneurysms.Extra-anatomic bypass surgery for thoracic aneurysm and pacemaker implantation have been excluded from the survey since 2015.Assist device implantations were not included in the total number of surgical procedures but were included in the survey.
A total of 70,769 cardiovascular surgeries, including 84 heart transplants, had been performed in 2019, with a 0.32% increase compared to that in 2018 (n=70,537).
Among the 9006 procedures for congenital heart disease conducted in 2019, 6890 were open-heart surgeries, with an overall hospital mortality rate of 1.7%.The number of surgeries for neonates and infants in 2019 did not significantly differ compared to that in 2009; however, hospital mortality improved from 10.7% to 7.1% for neonates and from 3.7% to 2.1% for infants.In 2019, atrial septal defect was the most common disease (1449 cases) as previously reported, with patients aged≥18 years accounting for 60.2% of atrial septal defect surgery.Ventricular septal defect (perimembranous/muscular), which had been the most common disease in 2015 and 2016, was the second most common disease (1072 cases).
Valvular heart disease procedures, excluding transcatheter procedures, were slightly performed more than that in the previous year.Moreover, isolated aortic valve replacement/repair with/without coronary artery bypass grafting (CABG) (n=10,268) was 3.0% lower than that in the previous year (n=10,584) but 0.5% higher than that 5 years ago (n=10,219), despite the rapid utilization of transcatheter aortic valve replacement (n=8664 in 2019).Isolated mitral valve replacement/repairs with/without CABG (n=5239) was 7.0% higher than that in the previous year (n=4898) and 8.0% higher than that 5 years ago (n= 4851).Aortic and mitral valve replacement with bioprosthesis were performed in 11,207 and 2987 cases, respectively.The rate at which bioprosthesis was used had dramatically increased from 30% in the early 2000s [4,5] to 83.0% and 73.0% in 2019 for aortic and mitral positions, respectively.Additionally, CABG was performed concurrently in 16.5% of all valvular procedures (17.2% in 2009 [2] and 17.3% in 2014 [3]).Valve repair was common in mitral and tricuspid valve positions (7632 and 6154 cases, respectively) but less common in aortic valve positions (257 patients, only 1.9% of all aortic valve procedures).Mitral valve repair accounted for 70.9% of all mitral valve procedures.Hospital mortality rates for single valve replacement for aortic and mitral positions were 2.9% and 6.4%, respectively, but only 1.2% for mitral valve repair.Moreover, hospital mortality rates for redo valve surgery for the aortic and mitral positions were 6.7% and 6.1%, respectively.Finally, overall hospital mortality rates did not significantly improve over the past 10 years (4.0% in 2009 [2], 3.1% in 2014 [3], and 3.3% in 2019).
Isolated CABG had been performed in 11,307 cases, accounting for only 68.3% of the procedures performed 10 years ago (n=16,536) [2].Of the aforementioned cases, 6509 (57.6%) underwent off-pump CABG, with a success rate of 97.8%.The percentage of planned off-pump CABG in 2019 was similar to that in 2018 when it fell below 60% for the first time since 2004 [4].Hospital mortality associated with primary elective CABG procedures among 9218 cases accounted for 1.6%, which is slightly higher than that in 2009 (1.2%) [2].Hospital mortality for primary emergency CABG among 1667 cases remained high (8.0%).The percentage of conversion from off-pump to on-pump CABG or on-pump beating-heart CABG was 2.2% among the primary elective CABG cases, with a hospital mortality rate of 8.9%.Patients with end-stage renal failure on dialysis had higher hospital mortality rates than overall mortality, regardless of surgical procedure (on-pump arrest, onpump beating, and off-pump).This study excluded concomitant CABGs alongside other major procedures under ? ? ?
?        Arrhythmia management was primarily performed as concomitant procedures in 6880 cases, with a hospital mortality rate of 3.2%.Pacemaker and implantable cardioverter-defibrillator implantation were not included in this category.
In 2019, 22,708 procedures for thoracic and thoracoabdominal aortae diseases were performed, among which aortic dissection and non-dissection accounted for 10,847 and 11,861, respectively.The number of surgeries for aortic dissection this year was 3.8% higher than that in the preceding year (n=10,453).Hospital mortality rates for the 6347 Stanford type A acute aortic dissections remained high (10.4%).The number of procedures for non-dissected aneurysms decreased by 1.2%, with a hospital mortality rate of 5.7% for all aneurysms and 4.2% and 19.7% for unruptured and ruptured aneurysms, respectively.Thoracic endovascular aortic repair (TEVAR) has been performed for aortic diseases at an increasing rate.Stent graft placement was performed in 4356 patients with aortic dissection, including 2387 TEVARs and 1969 open stent graftings.Moreover, 1470 and 267 cases underwent TEVAR and open stent grafting for type B chronic aortic dissection, accounting for 61.6% and 13.6% of the total number of cases, respectively.Hospital mortality rates associated with simple TEVAR for type B aortic dissection were 8.0% and 2.1% for acute and chronic cases, respectively.Stent graft placement was performed in 5087 patients with non-dissected aortic aneurysms, among which 4072 were TEVARs (an 11.8% increase compared to that in 2018, n=3641) and 1499 were open stent graftings (a 3.7% increase compared to that in 2018, n=1446).Hospital mortality rates were 3.7% and 18.7% for TEVARs and 5.8% and 15.2% for open stenting in unruptured and ruptured aneurysms, respectively.

(B) General thoracic surgery
The 2019 survey of general thoracic surgeries comprised 679 surgical units, with bulk data submitted via a web- based collection system established by the NCD [1].General thoracic surgery departments reported 91,626 procedures in 2019 (Table 7), which is 2.2 times more than that in 2000 and approximately 14,500 more procedures than that in 2014 (Fig. 2).In 2019, 48,052 procedures for primary lung cancer had been performed which continued to increase annually.Accordingly, the number of procedures in 2019 was 2.6 times higher than that in 2000, with lung cancer procedures accounting for 52% of all general thoracic surgeries.
Information about the number of video-assisted thoracoscopic surgery (VATS), which is defined as surgical procedures using a skin incision less than 8 cm including a mini-thoracotomy (hybrid) approach, have been available since the 2015 annual report.Tables 8, 9, 11, 14, 15, 16, 18, 19, 20, 21, 22, and 24, 25, 26 present the number of VATS procedures for benign pulmonary tumors, primary lung cancer, metastatic pulmonary tumor, chest wall tumor, mediastinal tumor, thymectomy for myasthenia gravis, nonneoplastic disease, empyema, descending necrotizing mediastinitis, bullous diseases, diaphragmatic hernia, chest trauma and the total number of VATS procedures in 2019, respectively.
A total of 2543 procedures for benign pulmonary tumors had been conducted in 2019 (Table 8).Hamartomas were the most frequent benign pulmonary tumors diagnosed, with 2437 patients (96%) undergoing VATS.
Tables 9 and 10 show additional information on primary malignant pulmonary tumors.Accordingly, the most frequently diagnosed lung cancer subtype was adenocarcinoma (71% of all lung cancers), followed by squamous cell carcinoma (18%).Sublobar resection was performed in 13,999 lung cancer cases (29% of all cases) and lobectomy in 33,455 cases (70% of all cases).Sleeve lobectomy was performed in 483 cases, while pneumonectomy was required in 278 cases (0.6% of all cases).VATS lobectomy was performed in 25,487 cases of lung cancer (76% of all lobectomy cases).Patients aged≥80 years who underwent lung cancer surgery accounted for 6739 (14%).Among  those who died within 30 days postoperatively, 107 and 66 died before and after hospital discharge, respectively.Overall, 173 patients died within 30 days postoperatively (30-day mortality rate, 0.4%), while 238 died before discharge (hospital mortality rate, 0.5%).Moreover, 30-day mortality rates according to the procedure were 0.1%, 0.3%, and 1.4% for segmentectomy, lobectomy, and pneumonectomy, respectively.Interstitial pneumonia had been the leading cause of death after lung cancer surgery, followed by pneumonia, respiratory failure, and cardiovascular events.
Table 11 shows the procedures for metastatic pulmonary tumors, of which 9329 were performed in 2019.Among such procedures, the most frequent primary tumor was colorectal cancer (51% of all cases).
A total of 117 procedures for tracheal tumors, including 60, 30, and 27 cases of primary malignant, metastatic, and benign tracheal tumors, respectively, were performed in  12).Overall, 682 pleural tumors had been diagnosed in 2019 (Table 13), with diffuse malignant pleural mesothelioma as the most frequent histologic diagnosis.Total pleurectomy was performed in 140 cases and extrapleural pneumonectomy in 43 cases.The 30-day mortality rate was 0% and 2.3% after total pleurectomy and extrapleural pneumonectomy, respectively, both of which had better outcomes than previously reported.
In 2019, 5,881 mediastinal tumors were resected, which is 10% higher compared to that in the previous year (Table 15).Thymic epithelial tumors, including 2280 thymomas, 351 thymic carcinomas, and 44 thymic carcinoids, were the most frequently diagnosed mediastinal tumor subtype in 2019.
A total of 499 patients underwent thymectomy for myasthenia gravis (Table 16), among which 337 procedures were associated with thymoma.
Overall, 23,717 patients underwent procedures for nonneoplastic disease.Accordingly, 2358 patients underwent lung resection for inflammatory lung diseases (Tables 17,  18), among which 475 and 336 patients were associated with mycobacterial and fungal infections, respectively.Procedures for inflammatory nodules were performed in cases where lung cancer was suspected preoperatively (928 cases, 39%).A total of 3298 procedures were performed for empyema (Table 19), among which 2597 (77%) were acute and 701 were chronic.Further, bronchopleural fistulas developed in 478 and 320 patients with acute and chronic empyema, respectively.The hospital mortality rate was 13% among patients with acute empyema with fistula.
Further, 93 operations were performed for descending necrotizing mediastinitis (Table 20), with a hospital mortality rate of 4.3%.
A total of 394 procedures were conducted for bullous diseases (Table 21), while only 13 patients underwent lung volume reduction surgery.
A total of 15,082 procedures were performed for pneumothorax (Table 22).Among the 11,200 procedures for spontaneous pneumothorax, 2762 (25%) were bullectomies alone, while 7714 (69%) required additional procedures, such as coverage with artificial material, as well as parietal pleurectomy.A total of 3,882 procedures for secondary pneumothorax were performed, with chronic obstructive pulmonary disease (COPD) being the most prevalent associated disease (2693 cases, 69%).The hospital mortality rate for secondary pneumothorax associated with COPD was 1.7%.
The 2019 survey reported 208 procedures for chest wall deformity (Table 23).However, this may have been underestimated because the Nuss procedure for pectus excavatum was more likely performed in pediatric surgery centers not associated with the Japanese Association for Thoracic Surgery.
Surgical treatment for diaphragmatic hernia was performed in 36 patients (Table 24).This figure may have been underestimated because procedures may have been classified as gastrointestinal surgery.The survey reported 469 procedures for chest trauma, excluding iatrogenic injuries (Table 25), with a hospital mortality rate of 5.5%.
With fistula 320 16 ( Without fistula 342 Sleeve resection with reconstruction 37 0 A total of 92 lung transplantations were performed in 2019 (Table 27), among which 80 and 12 were from braindead and living-related donors, respectively.
The number of VATS procedures has continued to increase annually, ultimately reaching 77,059 (84% of all general thoracic surgeries) in 2019 (Table 28).

(C) Esophageal surgery
In 2018, the data collection method for esophageal surgery had been modified from self-reports using questionnaire sheets following each institution belonging to the Japanese Association for Thoracic Surgery to an automatic package downloaded from the NCD in Japan.Consequently, the registry excluded data for non-surgical cases with esophageal diseases.Furthermore, data regarding the histological classification of malignant tumors, multiple primary cancers, and mortality rates for cases with combined resection of other organs could not be registered because they were not included in the NCD.Instead, detailed data regarding postoperative surgical and non-surgical complications were collected from the NCD.Moreover, data regarding surgeries for corrosive esophageal strictures and salvage surgeries for esophageal cancer had been exceptionally registered by participating institutions.
Thoracoscopic and/or laparoscopic esophagectomy was utilized in 1843 (76.8%) and 2687 (71.4%) patients with superficial and advanced cancer, respectively.Patients who underwent thoracoscopic and/or laparoscopic surgery (minimally invasive esophagectomy: MIE) for superficial or advanced cancer have been increasing, whereas that of open surgery, especially for advanced cancer, has been decreasing annually (Fig. 4).Mediastinoscopic esophagectomy was performed for 126 (5.3%) and 112 (3.0%) patients with superficial and advanced esophageal cancer, respectively.Robot-assisted esophagectomy was performed for 295 (12.3%) and 374 (9.9%) patients with superficial and advanced esophageal cancer, respectively.Patients who underwent robot-assisted surgery are increasing for both superficial and advancer esophageal cancers compared to that in 2018 (6.8% and 4.2% in 2018, respectively).Hospital mortality rates within 30 days after thoracoscopic and/or laparoscopic esophagectomy were 0.3% and 1.0% for patients with superficial and advanced cancer, respectively (Table 35).Detailed data collection regarding postoperative surgical and non-surgical complications was initiated in 2018.Overall, 1346 (21.8%) of 6161 patients developed grade III or higher complications based on the Clavien-Dindo classification in 2019.Among surgical complications, anastomotic leakage and recurrent nerve palsy occurred in 14.0% and 14.3% of the patients who underwent right transthoracic esophagectomy, in 12.3% and 14.6% of those who underwent robot-assisted esophagectomy, and in 19.7% and 24.8% of those who underwent mediastinoscopic esophagectomy, respectively.Among non-surgical postoperative complications, pneumonia occurred in 14.5% of the patients, 4.4% of whom underwent unplanned intubation.The possible advantage in postoperative pneumonia in patients with mediastinoscopic esophagectomy in 2018 was not observed this year.Postoperative pulmonary embolism occurred in 0.9% of the patients.These complication rates, including the others, were similar to those in 2018.
We aim to continue our efforts in collecting comprehensive survey data through more active collaboration with the Japan Esophageal Society and other related institutions.

( 2 )
Ischemic heart disease (total, (A) ?(B) ; 12,603) (A) Isolated CABG (total; (a)?(b); 11307) (a-1) On-pump arrest CABG (total;2491) % mortality LMT includes LMT alone or LMT with other branch diseases CABG coronary artery bypass grafting; 1VD one-vessel disease; 2VD two-vessel disease; 3VD three-vessel disease; LMT left main trunk; SVG saphenous vein graft (a-2) On-pump beating CABG (total;2% mortality LMT includes LMT alone or LMT with other branch diseases CABG coronary artery bypass grafting; 1VD one-vessel disease; 2VD two-vessel disease; 3VD three-vessel disease; LMT left main trunk; SVG saphenous vein graftTable 2 Off-pump CABG (total;6509) (Including cases of planned off-pump CABG in which, during surgery, the change is made to an on-pump CABG or on-pump beating-heart procedure) % mortality LMT includes LMT alone or LMT with other branch diseases CABG coronary artery bypass grafting; 1VD one-vessel disease; 2VD two-vessel disease; 3VD three-vessel disease; LMT left main trunk; SVG saphenous vein graft (c) Cases of conversion, during surgery, from off-pump CABG to on-pump CABG or on-pump beating-heart CABG (these cases are also included in category (b)) % mortality CABG coronary artery bypass grafting % mortality CPB cardiopulmonary bypass (3) Operation for arrhythmia (total;6880 % mortality WPW Wolff-Parkinson-White syndrome; IHD ischemic heart disease Except for 247 isolated cases, all remaining 6633 cases are doubly allocated, one for this subgroup and the other for the subgroup corresponding to the concomitant operations (6) HOCM and DCM (total; 278% mortality HOCM hypertrophic obstructive cardiomyopathy; DCM dilated cardiomyopathy; AVR aortic valve replacement; MVR mitral valve replacement; MVP mitral valve repair; CABG coronary artery bypass graftingTable 2 % mortality AVR aortic valve replacement; MVR mitral valve replacement; CABG coronary artery bypass grafting (7) Other open-heart operation (total; % mortality Ao aorta; AVP aortic valve repair; AVR aortic valve replacement; MVP mitral valve repair; MVR mitral valve replacement; CABG coronary artery bypass grafting; TEVAR thoracic endovascular aortic (aneurysm) repair Acute, within 2 weeks from the onsetTable 3

Table 8
Benign pulmonary tumor

Table 9
Primary malignant pulmonary tumor

Table 26
summarizes the procedures for other diseases, including 110 and 118 cases of arteriovenous malformation and pulmonary sequestration, respectively.

Table 28
Video-assisted thoracic surgery

Table 32
Operation of lung cancer invading the chest wall of the apex

Table 33
Distribution of number of esophageal operations in 2019 in each institution