1.Experimental Study of the Dynamic Fontan Operation with an Electrical Preconditioned Skeletal Muscle Ventricle for the Univentricular Heart.
Yoko Matsumura ; Kiyozo Morita ; Katsushi Kinouchi
Japanese Journal of Cardiovascular Surgery 2003;32(2):64-68
We have studied potential for pulmonary circulational assist by the dynamic Fontan model with a skeletal muscle ventricle (SMV) constructed using the latissimus dorsi muscles of 5 dogs. After 2 weeks of vascular delay, the SMV was electrically preconditioned for 8 weeks. Under cardiopulmonary bypass (CPB), the right heart (RV) bypass model was established with the SMV anastomosed between the right atrium and pulmonary trunk. The SMV was paced at a burst frequency of 25Hz, 60/min, with an asynchronization ratio. The aortic pressure (AoP), pulmonary arterial pressure (PAP), central venous pressure (CVP), and pulmonary flow (PAF) were measured. Just after on-SMV, PAP and PAF increased, CVP decreased. CVP decreased from 17±1.4mmHg to 13.5±0.7mmHg (p<0.05). PAP increased from 20±2.8/19±1.6mmHg (non-pulsatile flow) to 37.5±4.9/18±2.1mmHg (pulsatile flow). After CPB, pulmonary vascular resistance (Rp) showed 5.9±1.5 Wood units corresponding to a high risk factor for the Fontan procedure. On this Rp, under off-SMV the CVP was 18mmHg and severe RV failure was recognized as PAF was 35% of the preoperative value. Under on-SMV, CVP decreased and PAF was almost the same as the preoperative value. On physiological CVP, an RV bypass model with intrathoracic SMV maintained PAF at the preoperative value under high Rp. We concluded that this model may be a viable surgical option for univentricular heart with high Rp, which may not be Fontan candidates.
2.New Staged Repair of Neonatal Tetralogy of Fallot with Severe Absent Pulmonary Valve Syndrome
Hiroo Kinami ; Kiyozo Morita ; Yoshihiro Ko ; Gen Shinohara ; Kazuhiro Hashimoto
Japanese Journal of Cardiovascular Surgery 2015;44(2):97-102
Primary repair of the tetralogy of Fallot with absent pulmonary valve syndrome (TOF/APV) is associated with high mortality rates of 17-33%, especially in neonates. Our standard strategy involves a staged repair with a first palliation, performed during the neonatal period, that includes main pulmonary septation with an ePTFE patch, pulmonary arterioplasty for reduction of vascular dilation, and a modified Blalock-Taussig shunt. We performed successful repairs on two neonates with TOF/APV, one symptomatic and the other non-symptomatic, with this strategy. Case 1 : A 7-day-old boy had TOF/APV, with progressively worsening respiratory distress. His left bronchi, superior vena cava and left atrium were compressed by a dilated pulmonary artery, which was repaired by emergency surgery. Decreasing the diameter of the pulmonary artery (PA index from 2,550 to 525) relieved the compressed organs. Case 2 : A 16-day-old boy with TOF/APV with a main pulmonary artery that increased in diameter from 8 to 17 mm in the course of a single day. He was treated in the same fashion as Case 1. At 1 year of age, an intracardiac repair with tricuspid anuuloplasty was performed successfully. This strategy is much safer than a primary repair and is a good choice for neonatal repair of TOF/APV.
3.Mid-Term Pulmonary Homograft Function for Right Ventricular Outflow Tract Reconstruction in the Ross Procedure.
Koji Nomura ; Hiromi Kurosawa ; Kiyozo Morita ; Hirokuni Naganuma ; Katsushi Kinouchi
Japanese Journal of Cardiovascular Surgery 2002;31(6):385-387
Fourteen patients (mean age 17.2 years, range 2 to 39 years) undergoing right ventricular outflow tract reconstruction for a Ross operation were studied between 1998 and 2000. Ten of 14 patients underwent Ross procedures and 4 received Ross-Konno procedures. Echocardiographic examination of the pulmonary homograf t was performed after surgery. The mean follow-up period was 23.1 months, ranging from 14 to 33 months. Mean peak velocity and peak gradient were 1.6±0.4m/s and 11.9±5.2mmHg, respectively. Three patients in whom echocardiography revealed a peak pulmonary gradient of 20mmHg or more were retrospectively analyzed with each catheterization data. All patients had no more than 10mmHg at the distal end of the homograft with no evidence of deformity or shrinkage. Only one patient had a trivial homograft valve regurgitation, however, no patient had more than mild pulmonary regurgitation. Patient age, donor age, and preservation period did not reveal any significant risk factor for homograft stenosis. Pulmonary homograft appears to be an excellent substitute for right ventricular outflow tract reconstruction during the mid-term postoperative period.
4.Surgical Reconstruction with Autologous Tissue in a Case of Isolated Unilateral Absence of the Right Pulmonary Artery
Yoshimasa Uno ; Kiyozo Morita ; Masahito Yamashiro ; Gen Shinohara ; Hiroshi Kagawa ; Kazuhiro Hashimoto
Japanese Journal of Cardiovascular Surgery 2009;38(2):156-159
Isolated unilateral absence of the right pulmonary artery without any intracardiac anomaly is a rare congenital cardiovascular disorder. We performed a successful surgical reconstruction with autologous tissue of this anomaly. The patient was a 1-month-old boy who had been transferred to our center at 3 days of age because of tachypnea and heart murmur. Multi-detector CT and radial angiography imaging revealed isolated unilateral absence of the right pulmonary artery and left patent ductus arteriosus. Conservative treatment did not help his progressive heart failure and pulmonary hypertension due to an acute increase of pulmonary blood flow. Therefore surgical correction was determined to avoid the worsening of those symptoms. Under cardiopulmonary bypass, the right pulmonary artery branching off from the brachiocephalic artery was removed and anastomosed to the main pulmonary artery with an autologous pericardium roll. Symptoms improved postoperatively and he was discharged in good condition on the 21st of postoperative day. Cardiac catheterization, 3 months later, showed excellent results.
5.A Case of a Coronary Arteriovenous Fistula Associated with a Right Single Coronary Artery
Katsushi Kinouchi ; Hiromi Kurosawa ; Kiyozo Morita ; Koji Nomura ; Hirokuni Naganuma ; Youkou Matsumura
Japanese Journal of Cardiovascular Surgery 2004;33(4):252-254
A 3-year-old girl was given a diagnosis of coronary arteriovenous fistula associated with a single right coronary artery on cardiac catheterization. The left coronary artery arose from the proximal part of the right coronary artery. The dilated left coronary artery ran in front of the right ventricular outflow tract and then divided into the left anterior descending branch and the left circumflex artery. A coronary arteriovenous fistula was in the left main coronary artery and opened into the right ventricular outflow tract. Under cardiopulmonary bypass and cardiac arrest, a transverse incision was made at the right ventricular outflow tract 1cm below the dilated vessel and the 5-mm oval-shaped orifice of the fistula was identified. This fistula was closed with a pledgetted mattress suture reinforced with over-and-over suture. Catheterization 8 months after surgery demonstrated no residual shunt and she has been doing well.
6.A Case of Mycotic Aneurysm of the Pulmonary Artery with Pulmonary Artery Fistula following Pulmonary Artery Banding
Yoshihiro Ko ; Kiyozo Morita ; Yoko Matsumura ; Katsushi Kinouchi ; Ken Nakamura ; Kazuhiro Hashimoto
Japanese Journal of Cardiovascular Surgery 2006;35(5):292-294
A 9-month-old boy who had been given a diagnosis of double outlet right ventricle (DORY), partial anomalous pulmonary venous return (PAPVR), ventricular septal defect (VSD), pulmonary hypertension (PH) and polysplenia with azygos connection, underwent pulmonary artery banding at the age of 6 months. At 2 months after surgery, a chest computed tomogram revealed a main pulmonary artery aneurysm and a main pulmonary artery-right pulmonary artery fistula caused by bacterial endocarditis due to a methicillin-resistant Staphylococcus epidermidis. We performed pulmonary arterioplasty and re-pulmonary artery banding for acute aggravation of cardiac insufficiency and obtained good results. This is an extremely rare case that was treated infectious pulmonary artery aneurysm and fistula after pulmonary artery banding.
7.Surgical Management of Perivalvular Leakage after Mitral Valve Replacement
Yoshimasa Sakamoto ; Kazuhiro Hashimoto ; Hiroshi Okuyama ; Shinichi Ishii ; Shingo Taguchi ; Takahiro Inoue ; Hiroshi Kagawa ; Kazuhiro Yamamoto ; Kiyozo Morita ; Ryuichi Nagahori
Japanese Journal of Cardiovascular Surgery 2008;37(1):13-16
Perivalvular leakage (PVL) is one of the serious complications of mitral valve replacement. Between 1991 and 2006, 9 patients with mitral PVL underwent reoperation. All of them had severe hemolytic anemia before surgery. The serum lactate dehydrogenase (LDH) level decreased from 2,366±780 IU/l to 599±426 IU/l after surgery. The site of PVL was accurately defined in 7 patients by echocardiography. PVL occurred around the posterior annulus in 3 patients, anterior annulus in 2, anterolateral commissure in 1, and posteromedial commissure in 1. The most frequent cause of PVL was annular calcification in 5 patients. Infection was only noted in 1 patient. In 4 patients, the prosthesis was replaced, while the leak was repaired in 5 patients. There was one operative death, due to multiple organ failure, and 4 late deaths. The cause of late death was cerebral infarction in 1 patient, subarachnoid hemorrhage in 1, sudden death in 1, and congestive heart failure (due to persistent PVL) in 1. Reoperation for PVL due to extensive annular calcification is associated with a high mortality rate and high recurrence rate, making this procedure both challenging and frustrating for surgeons.
8.Sutureless Repair of Pulmonary Venous Obstruction after Repair of Total Anomalous Pulmonary Venous Connection (1a+2a)
Katsushi Kinouchi ; Kiyozo Morita ; Kazuhiro Hashimoto ; Koji Nomura ; Yoshimasa Uno ; Youkou Matsumura ; Ken Nakamura ; Takayuki Abe ; Hiroshi Kagawa ; Tooru Sakuma
Japanese Journal of Cardiovascular Surgery 2006;35(6):328-332
Pulmonary venous obstruction (PVO) after repair of total anomalous pulmonary venous connection remains a significant problem. Once it occurs, it not infrequently recurs. A 14-month-old boy with recurrent pulmonary venous obstruction after repair of mixed type total anomalous pulmonary venous connection was successfully treated by the method of sutureless in situ pericardial repair and anastomosis of the left pulmonary vein to the left atrial appendage. His postoperative course was uneventful. Cardiac catheterization at 2 years and 9 months after the re-redo operation showed successful relief of PVO with marked reduction of pulmonary hypertension. In addition, multidetector computed tomography (MDCT) performed 3 years and 1 month after the operation showed no pulmonary vein obstruction.
9.Subcutaneous Self-Injection Therapy of Heparin for a Case of Ebstein Disease with Artificial Valve and Warfarin-Induced Skin Ulcer
Yoshimasa UNO ; Kiyozo MORITA ; Gen SHINOHARA ; Takashi KUNIHARA
Japanese Journal of Cardiovascular Surgery 2020;49(4):188-191
We report a successful conversion of anti-coagulant therapy from warfarin to heparin for a case of mechanical heart valve and warfarin-induced skin ulcer. A 57-year-old female who was diagnosed with Ebstein disease and underwent mechanical valve replacement suffered from a recurring and resistant leg skin ulcer. Nine years after the induction of warfarin, her right leg skin ulcer occurred suddenly and worsened gradually. No dermatological treatment could cure it and three auto-skin transplantations were performed in the past four years. The definitive cause of the ulcer could not be diagnosed by any laboratory study or image inspection. Further, after every transplant surgery, the resumption of warfarin had made her ulcer recur and worsen. Therefore, we finally came to think of this disease as the warfarin-induced skin ulcer. To avoid warfarin, subcutaneous self-injection therapy of Heparin-Ca was applied as her anti-coagulation after the 4th transplant surgery. The patient was discharged from hospital on post-operative day 78 with a good condition of the transplanted skin graft and right leg. An adequate level of APTT could be maintained with injections of 10,000 units of Heparin-Ca twice a day and data on D Dimer and cardiac echography show no thromboembolism at the out-patient visits. The result of auto-skin transplantation is also a good course under this therapy. As we have very few reports concerning heparin self-injection therapy for artificial valves, it is very important that careful observation should be continued.
10.A Case of Successful Valve Repair in Traumatic Aortic Regurgitation Associated with the Dilated Aortic Annulus
Satoshi ARIMURA ; Mitsutaka NAKAO ; Naritomo NISHIOKA ; Yohkoh MATSUMURA ; Michio YOSHITAKE ; Ryuichi NAGAHORI ; Ko BANDO ; Kiyozo MORITA ; Takashi KUNIHARA
Japanese Journal of Cardiovascular Surgery 2020;49(6):358-361
Here, we present a case of successful aortic valve repair of traumatic aortic regurgitation (AR). A man in his early twenties had a chest blunt trauma due to a bicycle accident 6 years earlier and suffered sternum fracture. He recovered without cardiovascular complications. Three months previously, a new diastolic murmur was detected on medical checkup. Transthoracic echocardiography (TTE) showed severe AR, and the left ventricular end-diastolic-/end-systolic dimension was 69/51 mm. Transesophageal echocardiography showed severe AR with perforation of the non-coronary cusp and dilatation of the aortic annulus (29.6 mm). Aortic valve repair was performed with an autologous pericardial patch and external suture annuloplasty. Postoperative TTE showed normal aortic valve function with trivial AR. He was discharged on postoperative day 11. Three months later, TTE showed trivial AR along with a reduced left ventricular dimension and improved left ventricular ejection fraction.