Longitudinal valvotomy of anterior leaflet for endoscopic transmitral myectomy for hypertrophic obstructive cardiomyopathy.

Transmitral myectomy for hypertrophic obstructive cardiomyopathy is compatible with minimally invasive surgery compared with traditional transaortic access. It has often been performed in conjunction with mitral valve replacement or temporary detachment of the anterior leaflet from its annulus. We present a novel approach: longitudinal incision at the midline of the anterior mitral leaflet for septal myectomy. The procedure is ideally conducted endoscopically or robotically through the right chest. Cardiopulmonary bypass is established in the usual manner. After cardioplegic arrest, the mitral valve is exposed, and the anterior mitral leaflet is incised longitudinally at the midline. Both parts of the leaflet are tentatively fixed to the atrial wall with sutures to keep them open. Using the look-up mode of a 30° scope, the right cusp of the aortic valve is observed. Myectomy is initiated close to the aortic annulus using the pure-cut mode of electrocautery and scissors, then extended apically as necessary. After myectomy, the anterior leaflet is reapproximated with interrupted sutures. This technique is simpler than the detachment of the anterior leaflet and does not require patch materials that could lead to durability issues for the reconstruction of the anterior leaflet.

Administration of anti-inflammatory M2 macrophages suppresses progression of angiotensin II-induced aortic aneurysm in mice.

Aortic aneurysm (AA) is a vascular disorder characterized pathologically by inflammatory cell invasion and extracellular matrix (ECM) degradation. It is known that regulation of the balance between pro-inflammatory M1 macrophages (M1Ms) and anti-inflammatory M2 macrophages (M2Ms) plays a pivotal role in AA stabilization. We investigated the effects of M2M administration in an apolipoprotein E-deficient (apoE-/-) mouse model in which AA was induced by angiotensin II (ATII) infusion. Mice received intraperitoneal administration of 1 million M2Ms 4 weeks after ATII infusion. Compared with a control group that was administered saline, the M2M group exhibited reduced AA expansion; decreased expression levels of interleukin (IL)-1ß, IL-6, tumor necrosis factor-α (TNF-α), and monocyte chemoattractant protein-1 (MCP-1); and a lower M1M/M2M ratio. Moreover, the M2M group exhibited upregulation of anti-inflammatory factors, including IL-4 and IL-10. PKH26-labeled M2Ms accounted for 6.5% of cells in the aneurysmal site and co-expressed CD206. Taken together, intraperitoneal administration of M2Ms inhibited AA expansion by reducing the inflammatory reaction via regulating the M1M/M2M ratio. This study shows that M2M administration might be useful for the treatment of AA.

Albuminuria Predicts Short-Term Worsening Renal Function After Transcatheter Aortic Valve Replacement.

Albuminuria is a major risk factor of cardiovascular events, however, the impact of albuminuria on clinical outcomes of patients undergoing transcatheter aortic valve replacement (TAVR) has not been fully investigated. This retrospective study included 206 patients who underwent TAVR for severe aortic stenosis. Patients were divided into two groups according to the preoperative urinary albumin-to-creatinine ratio (ACR): high (ACR ≥ 30 mg/g) and low (ACR < 30 mg/g). The incidence of 1-month worsening renal function (WRF), defined as a decrease in estimated glomerular filtration rate (eGFR) ≥10% from baseline after TAVR, was investigated. Patients with high ACR had acute kidney injury (8.5% vs. 1.0%, p = 0.01) and 1-month WRF (29.2% vs. 12.0%, p = 0.002) more frequently than those with low ACR. High ACR was independently associated with 1-month WRF (odds ratio, 3.72; 95% confidence interval, 1.72-8.08; p < 0.001). Albuminuria can be a useful predictor of deterioration of renal function at various time points after TAVR.

[Mitral and Aortic Valve Replacement and Tricuspid Valve Repair in a Patient with Metal Allergy].

We report a 63-year-old woman came to our hospital with exertional dyspnea, palpitations, and abdominal distention. Echocardiography showed mitral, aortic, and tricuspid valve insufficiency, for which surgery was indicated. Twenty-six years ago, during dental therapy, she was diagnosed with metal allergy. A patch test demonstrated allergic reactions to manganese, chromium, and zinc. The patient underwent mitral and aortic valve replacement with the On-X prosthetic heart valve, which is primarily made of titanium and devoid of the allergens. She also underwent tricuspid valve repair with a Contour 3D annuloplasty ring, which is made of titanium alloy. She manifested no allergic symptoms three years after surgery. This case elucidates the importance of history taking regarding metal allergy and identification of allergens by patch testing in patients undergoing cardiac surgery involving metal device implantation.

Use of a cutting stapler to excise a left atrial appendage in minimally invasive cardiac surgery.

PURPOSE: A cutting stapler is a well-established instrument in many surgical fields. However, its efficacy and safety have not been proven yet in resecting a left atrial appendage (LAA) in minimally invasive cardiac surgery (MICS). METHODS: A cutting stapler was used to resect the LAA in 98 consecutive patients who underwent MICS. Of these, 26 patients underwent aortic valve replacement, 72 mitral valve repair/replacement, 25 tricuspid annuloplasty, 7 closure of atrial septal defect, and 26 the Maze procedure (contains overlapping). The ascending aorta was elevated using a retractor, and a 12-mm shaft motor-driven cutting stapler was inserted through the transverse sinus. As a control group, 150 patients who underwent suture resection/closure of the LAA either from inside or outside were compared. RESULTS: There was one mortality in each group. They were not related to the LAA resection/closure. In the suture group, the LAA suture was taken down in one patient because of a suspected obstruction of the circumflex artery, and two patients had re-exploration for bleeding from the LAA. In the stapler group, there was no complication related with the LAA. The rate of complication did not reach a statistical difference. CONCLUSION: A cutting stapler is considered to be a useful instrument to resect the LAA in MICS.

[Totally Endoscopic Aortic Valve Replacement Using the Three-dimensional Endoscope].

Totally endoscopic aortic valve replacement (TE-AVR) is still challenging, and few series report exist even today. In 2015, we started to use three-dimensional (3D) endoscope and we also introduced TE-AVR. Patient is placed in the partial left lateral position. The main wound is created in right antero-lateral 4th intercostal space through 4 cm skin incision. No rib spreader is used. 3D endoscope is inserted on the mid-axillary line. A 5 mm trocar was inserted in the 3rd intercostal space, thus creating 3-port setting similarly to that for endoscopic mitral valve surgery. All sutures are tied using a knot-pusher. We have performed 106 cases of TE-AVR. Compared with transaxillary AVR, there were no significant differences between the 2 groups in the hospital deaths or MACCE. Postoperative hospital stays became shorter in totally endoscopic group. In conclusion, TE-AVR was possible through 3 ports created in the right antero-lateral chest similarly to the endoscopic mitral valve surgery. Transaxillary approach seemed to be suitable for the TE-AVR. By adopting common approach for both mitral valve surgery and aortic valve surgery, endoscopic double valve surgery could be performed seamlessly.

Totally endoscopic aortic valve replacement via an anterolateral approach using a standard prosthesis.

OBJECTIVES: Totally endoscopic aortic valve replacement (AVR) is still a challenging operation, and only a few series reports exist in the literature. The purposes of this study were to establish a method for endoscopic AVR and evaluate its initial results. METHODS: A total of 47 patients (median age 76 years, 17 men) underwent endoscopic AVR. The main wound was created in the right anterolateral 4th intercostal space through a 4-cm skin incision. No rib spreader was used. A 3-dimensional endoscope was inserted at the midaxillary line. A 5.5-mm trocar was inserted in the 3rd intercostal space, thus creating a 3-port setting similar to that used for endoscopic mitral valve surgery. A standard prosthesis was used, and the sutures were tied using a knot pusher. Results were compared with those of 157 patients who underwent right transaxillary AVR with direct vision plus endoscopic assist. RESULTS: Patient backgrounds did not differ significantly between the 2 groups. No deaths occurred in the entire series. There was no conversion to thoracotomy or sternotomy in the endoscopic AVR group. The complication rate did not differ significantly between the 2 groups. The total operating time was significantly shorter in endoscopic AVR (188-206 min); the cardiopulmonary bypass time (130-128 min) and the cross-clamp time (90-95 min) did not differ significantly (median, endoscopic AVR, right transaxillary AVR). Two patients underwent endoscopic double-valve (aortic and mitral) surgery under the same conditions. CONCLUSIONS: Endoscopic AVR was possible through 3 ports created in the right anterolateral chest, similar to the procedure for endoscopic mitral valve surgery. By adopting a common approach for both the aortic and the mitral valve operations, endoscopic double-valve surgery can be performed seamlessly.

Three-port totally endoscopic repair vs conventional median sternotomy for atrial septal defect.

PURPOSES: We assessed the validity of three-port totally endoscopic repair (3PTER) for atrial septal defect (ASD). METHODS: Between February, 2000 and November, 2017, 151 patients underwent surgery for ASD. Forty-seven patients underwent 3PTER as minimally invasive cardiac surgery (MICS) and 104 patients underwent conventional median sternotomy (CMS). Propensity matching yielded 94 matched patients (47 vs 47). We compared the early results between the groups. The 3PTER technique was performed with the patient in the partial left lateral position, under cardio-pulmonary bypass (CPB) established through a groin incision. The three ports consisted of a main incision (3 cm), a trocar for the left-handed instrument, and a camera port in right antero-lateral chest. RESULTS: MICS needed longer cross clamp and CPB times (57, 48-86 vs 24, 16-30 min, p < 0.01 and 115, 106-131 vs 53, 43-80 min, p < 0.01, respectively)*, although the operation time and hospital stay were significantly shorter (180, 159-203 vs 190, 161-225 min, p = 0.024 and 6.0, 6-8 vs 15, 13-19 days, p < 0.01, respectively)*. The intra-operative and postoperative bleeding were significantly less in MICS than CMS (20, 5-40 vs 225, 130-287.5 p < 0.01 and 200, 145-290 vs 340, 250-535 ml, p < 0.01, respectively)*. *: median, 25th-75th percentile. CONCLUSION: Irrespective of the longer CPB and cross-clamp time than for CMS, MICS had a shorter operation time, less bleeding, and resulted in quicker recovery. The 3PTER was safe and cosmetically excellent.

Trans-right axillary aortic valve replacement: propensity-matched comparison with standard sternotomy approach.

OBJECTIVES: We developed trans-right axillary aortic valve replacement (TAX-AVR) as a more cosmetically superior approach to minimally invasive AVR. We herein retrospectively compared the safety and invasiveness between TAX-AVR and conventional AVR (C-AVR). METHODS: TAX-AVR was performed under femorofemoral cardiopulmonary bypass. Creation of a small right axillary vertical skin incision was followed by anterolateral intercostal thoracotomy. AVR was performed using long-shafted minimally invasive instruments, a knot pusher and endoscopic assistance. From January 2007 to June 2016, 112 patients underwent TAX-AVR and 183 controls underwent first-time, isolated non-emergency C-AVR. The factors used to calculate the European System for Cardiac Operative Risk Evaluation score and Society of Thoracic Surgeons score were adopted for propensity matching. Early mortality and major adverse cardiac and cerebral events were compared. The procedural time, postoperative intensive care unit stay and hospital stay were compared as markers of invasiveness. RESULTS: Propensity matching generated 108 matched pairs with similar backgrounds. Thirty-day mortality occurred in 0 and 1 patient in the TAX-AVR and C-AVR groups, respectively. The major adverse cardiac and cerebral events rates were not significantly different between the groups. The average aortic clamp time was longer (100 vs 94 min), but the intensive care unit stay (1.2 vs 1.8 days) and hospital stay (10.0 vs 12.5 days) were shorter in the TAX-AVR group. Postoperative blood loss, transfusion and atrial fibrillation were lower in the TAX-AVR group. The average prosthesis size was 22 mm in both groups. CONCLUSIONS: TAX-AVR is as safe as C-AVR and less invasive in terms of a shorter recovery period.

Long-term patency of on- and off-pump coronary artery bypass grafting with bilateral internal thoracic arteries: the significance of late string sign development in the off-pump technique.

OBJECTIVES: This study aimed to examine the effect of off-pump coronary artery bypass grafting (CABG) in patients who underwent revascularization with bilateral internal thoracic arteries (ITAs). METHODS: Between January 2000 and December 2014, 499 patients underwent isolated CABG with bilateral ITAs for complete revascularization of the left coronary system at our institution. On-pump CABG was performed in 137 patients, and off-pump CABG was performed in 362 patients. We retrospectively compared the clinical outcomes and patency of the ITAs. RESULTS: The off-pump group showed less respiratory failure and required a shorter postoperative stay than the on-pump group. The survival probability, freedom from cardiac events and early graft patency were similar in both groups. Five-year patency of the ITA anastomosed to the left anterior descending artery was significantly greater in the on-pump group than in the off-pump group (98.8% vs 91.2%, P = 0.010). The incidence of string change in the off-pump group was higher than that in the on-pump group (P = 0.017). There was no significant difference between the groups in the 5-year patency of the ITA anastomosed to the left circumflex artery (on-pump group: 93.8%, off-pump group: 91.8%; P = 0.46). CONCLUSIONS: The early graft patency and the late patency of the ITA anastomosed to the left circumflex artery between the groups were similar, implying an equivalent quality of anastomoses. However, the patency of the ITA anastomosed to the left anterior descending artery in the off-pump group showed late deterioration, mainly because of string sign development.

Three-port (one incision plus two-port) endoscopic mitral valve surgery without robotic assistance.

OBJECTIVES: Totally endoscopic minimally invasive mitral valve surgery (MIMVS) is technically demanding and often performed with robotic assistance. We hypothesized that three-port video-assisted thoracic surgery (VATS) would facilitate endoscopic MIMVS and evaluated its feasibility and safety. METHODS: From October 2010 to June 2016, we performed first-time MIMVS in 250 consecutive patients (122 male), with median age of 65 years (54-73 years, 25-75 percentile). The thoracic access ports comprised one small (3-5 cm) thoracotomy without a rib spreader plus two trocars (one for the endoscope and one for left-handed instruments), thus establishing triangular three-port VATS. Cannulas, an aortic clamp, and a left atrial retractor were inserted through the thoracotomy, and right-handed instruments were inserted through the remaining space. Cardiopulmonary bypass was established through a groin incision. RESULTS: The etiology of the mitral valve lesion was myxomatous degeneration in 70% of patients, rheumatic disease in 9%, infectious endocarditis in 6%, and other conditions in 15%. Mitral valve repair was performed in 233 patients and replacement in 27. Two patients underwent conversion to replacement after attempted repair. Forty-nine patients underwent tricuspid annuloplasty, and 45 underwent the Maze procedure. One in-hospital death occurred within 30 days. Two patients developed stroke, three underwent re-exploration for bleeding, one developed low output syndrome, and one required new haemodialysis. The aortic clamp, bypass, and total operation times were 119 (94-149), 166 (134-200) and 237 (204-285) min, respectively, median (25-75%). The 5-year survival and reoperation-free rates were 98.3% ± 0.9% and 96.9% ± 1.2%, respectively. CONCLUSIONS: Three-port endoscopic MIMVS appears reproducible and safe.

Effect of modified proximal anastomosis of the free right internal thoracic artery: piggyback and foldback techniques.

OBJECTIVES: Few studies have reported the free right internal thoracic artery (RITA) being used in an aorto-coronary fashion. This study aimed to evaluate the free RITA with modified proximal anastomosis in an aorto-coronary fashion. METHODS: Between January 2000 and December 2012, 282 patients underwent coronary artery bypass grafting with bilateral internal thoracic arteries for complete revascularization of the left coronary system at our institution. The left internal thoracic artery (LITA) was anastomosed to the left anterior descending artery (LAD) and the RITA was anastomosed to the left circumflex branches (LCX). The RITA was used as a free graft in 213 patients (free group) and as an in situ graft in 69 patients (in situ group). Proximal anastomosis of the free RITA onto the ascending aorta was performed in two different ways. We compared early and late results and graft patency of the free RITA with those of the in situ RITA retrospectively. RESULTS: The numbers of anastomoses per patient and anastomoses of the RITA were larger in the free group than in the in situ group (P < 0.01). There was no significant difference in postoperative survival between the groups (free group: 93.3% vs in situ group: 90.0%, P = 0.82). The 5-year patency of the free RITA was higher than that of the in situ RITA (97.0 vs 80.3%, P = 0.01). The 5-year patency of the free RITA was comparable with that of the in situ LITA anastomosed to the LAD (97.0 vs 92.9%, P = 0.28). CONCLUSIONS: The free RITA anastomosed to the LCX might have better late patency than the in situ RITA. The free RITA with modified proximal anastomosis in an aorto-coronary fashion enables complete revascularization of the left coronary system with the in situ LITA to the LAD.

Mitral valve plasty for a hammock mitral valve in an adult patient.

A 50-year old woman presented with arterial thrombosis in the right leg. Echocardiography revealed a mobile left atrial thrombus and severe mitral stenosis. She underwent a left atrial thrombectomy, the maze procedure and mitral valve plasty. Anterior and posterior mitral leaflets arose directly from the anterior papillary muscle, and from the posterior papillary muscle intervened by short chordae. This suggested a hammock mitral valve. A posterior papillary muscle division and commissurotomy were performed. The anterior leaflet was divided off the anterior papillary muscle, then extended by a triangular-shaped autologous pericardial patch and apically reattached. The postoperative mean pressure gradient of the mitral valve was 2.2 mmHg, and there was no regurgitation. The patient was in NYHA Class 1 and in sinus rhythm, 14 months after the operation.

[Reoperative cardiac surgery after previous coronary artery bypass grafting].

Reoperative cardiac surgery after coronary artery bypass grafting( CABG) has been increasing. We reviewed 25 cases of reoperative cardiac surgery after CABG. Re-CABG was not included in this study. The patients consisted of 15 men and 10 women. The mean patient age was 74.4±6.3 years old. The reoperations were performed 6.3±5.1 years after CABG. They consisted of 7 aortic valve surgeries, 2 double valve surgeries, 12 mitral valve surgeries, and 4 total arch replacements. Resternotomy was performed in 20 cases, while right thoracotomy was performed in 5 cases. Internal thoracic artery( ITA)grafts had been used in 24 cases, and 22 of them were patent. Fifteen operations were performed under cardioplegic arrest with the patent ITA graft clamped from the left pleural space, while 5 operations were performed under perfused ventricular fibrillation with hypothermia. No differences were observed between the 2 groups in terms of cardiopulmonary bypass (CPB) time and peak creatine kinase MB (CK-MB). Operative mortality was 4% (1/25). To clamp left internal thoracic artery (LITA) graft from the left pleural space is easy and safe. In case clamping the patent graft is difficult, perfused ventricular fibrillation with hypothermia is a useful alternative.

Seamless reconstruction of mitral leaflet and chordae with one piece of pericardium.

OBJECTIVES: Mitral valve repair is challenging when enough pliable mitral leaflets and chordae are not left intact because of extensive infective endocarditis or chronic sclerotic degeneration. For those cases, we developed a simple method to reconstruct defective leaflets and chordae en bloc with a piece of pericardium, and the mid-term results were evaluated. METHODS: From January 2009 to November 2013, 25 patients with the mean age of 63 (range 20-88) years underwent this operation. The causes of mitral regurgitation were infective endocarditis in 8, sclerotic degeneration in 8, leaflet dehiscence of previous repair in 2, mitral annular calcification in 3, rheumatic in 2 and congenital in 2. After complete debridement of infected or consolidated tissue, we reconstructed defective mitral leaflets and chordae en bloc with a piece of glutaraldehyde-treated autologous pericardium. To substitute posterior leaflet and chordae, the pericardium was trimmed into a narrow pentagonal shape. The pointed end was attached directly to the corresponding papillary muscle, basal side edges to remnant leaflets on both sides, and the base to the annulus. For anterior leaflet, the pericardium was trimmed into a triangular shape if the lesion was confined in the left or right half or into a double-triangle shape if the lesion involved whole anterior leaflet. The summit of triangle was fixed to corresponding papillary muscle, and the base to remnant anterior leaflet, thus reconstructing coaptation zone and chordae seamlessly. RESULTS: There was no hospital death, and mitral regurgitation at discharge was none or trivial in all patients. During 1-59 months (mean 12.7) of complete follow-up, death, infection or hemolysis was not observed. In one patient, mitral regurgitation recurred 8 months postoperatively because the fixation suture of the pericardium to the papillary muscle broke. The valve was re-repaired with re-attaching the leg of the pericardium. Regurgitation was less than moderate in all other patients. One patient with rheumatic lesion who underwent anterior leaflet repair and Maze operation suffered minor stroke 1 month postoperatively but fully recovered. CONCLUSIONS: Seamless reconstruction of leaflets and chordae with pericardium seemed promising to repair extensively destructed mitral valve.

[Ascending aorta replacement late after aortic valve replacement].

Replacement of the asceding aorta is indicated in patients undergoing aortic valve replacement( AVR), if the diameter of the ascending aorta is greater than 5.0 cm. If the diameter of the asceding aorta is from 4.0 to 5.0 cm, it was arguable whether replacement of the ascending aorta should be performed. Nine patients who underwent reoperative ascending aorta replacement after AVR were reviewed retrospectively. Reoperation on the asending aorta replacement was performed 11.8±7.2 years (range 1y5m~23y3m) after AVR. Mean patient age was 69.9±6.3 (range 60~81). In 2 cases, reoperations were performed early year after AVR. Although ascending aorta was dilated at the 1st operation, replacement wasn't performed for the age and minimally invasive cardiac surgery (MICS). In 3 cases, reoperations were performed more than 10 years later. On these cases, ascending aorta aneurysm and dissection occurred with no pain and were pointed out by computed tomography(CT) or ultrasonic cardiogram(UCG). We think that patients with dilatation of the ascending aorta should undergo AVR and aorta replacement at the 1st operation regardness of age. It is important that patients who underwent AVR should undergo a regular checkup on the ascending aorta.