Conduction disorders after perimembranous ventricular septal defect closure: continuous versus interrupted suturing techniques

OBJECTIVES

The aim of this study was to investigate postoperative conduction disorder differences between continuous and interrupted suturing techniques for the closure of perimembranous outlet-type ventricular septal defects (VSDs) in both tetralogy of Fallot (ToF) and isolated VSD cases.

METHODS

Patients aged 4 years or younger who underwent VSD closure for ToF (n = 112) or isolated perimembranous outlet-type VSD (n = 73) from April 2010 to December 2018 at 3 centres were reviewed. Patients either received continuous suturing for ToF (C-ToF, n = 58) or isolated VSD (C-VSD, n = 50), or interrupted suturing for ToF (I-ToF, n = 54) or isolated VSD (I-VSD, n = 23). Cohorts did not differ in preoperative characteristics. Postoperative conduction disorder differences upon discharge and postoperative year 1 (POY1) were evaluated by electrocardiography.

RESULTS

The C-ToF group showed significantly shorter PQ intervals (124.0 vs 133.5 ms; P = 0.042 upon discharge, 125.3 vs 133.5 ms; P = 0.045 at POY1) and QRS durations (98.0 vs 106.2 ms; P = 0.031 upon discharge, 97.3 vs 102.5 ms; P = 0.040 at POY1) than the I-ToF group. Right bundle branch block incidence was significantly lower in the C-ToF versus I-ToF groups (56.8 vs 75.9; P = 0.045 upon discharge, 56.8 vs 75.9; P = 0.045 at POY1). Heart rates were significantly lower in the C-ToF versus I-ToF groups at POY1 (109.2 vs 119.3 bpm; P < 0.001). No parameters significantly differed between C-VSD and I-VSD groups. Multivariable analyses confirmed the group (C-ToF versus I-ToF) as a significant covariate in postoperative heart rate, PQ interval, QRS duration and right bundle branch block outcomes at POY1 (P = 0.013, 0.027, 0.013 and 0.014, respectively).

CONCLUSIONS

A continuous suturing technique for the closure of outlet-type VSD in ToF could reduce the incidence of postoperative right bundle branch block, shorten the PQ interval and lower heart rate.

SUBJECT COLLECTION

110, 138, 139.

Architecture matters: Tissue preservation strategies for tetralogy of Fallot repair

BACKGROUND

Great variability exists in repair strategies for the tetralogy of Fallot. While transannular patching, as introduced by Kirklin, was a breakthrough for primary repair, pulmonary regurgitation and a need for reoperation have led to the development of methods that preserve the natural morphology of the right ventricular outflow tract.

METHODS

State-of-the-art details of tetralogy of Fallot repair are explained from the standpoint of architectural preservation, especially with regard to sparing native tissue such as the annulus, valve, or infundibulum. Particular attention is given to the latest technical details of each approach, benefits and disadvantages, and any long-term data available.

RESULTS

The choice of procedure is complex and unique to each case as transannular patching alone may carry long-term pulmonary risks. Modifications that spare the annulus, valves, or infundibulum may thus be essential as preservation of natural morphology has resulted in excellent mid-term results.

CONCLUSIONS

The complexity of tetralogy of Fallot repair demands constant attention to clinical presentation and vigilance against long-term sequelae. Techniques will continue to improve over time as long-term data guides the refinement of these innovative surgical methods.

Slit Orifice Aortic Cusp Extension Technique for Small Bicuspid Valves

We describe a modification to the aortic cusp extension technique that eliminates aortic regurgitation in pediatric small bicuspid valves. This simple and reproducible cusp extension technique secures coaptation and commissure suspension of the reconstructed aortic valve and may act as a bridge option for forthcoming reoperations.

A Case of a Figure of Eight Atrial Tachycardia after a Pulmonary Vein Antrum Isolation of Atrial Fibrillation

A 66-year-old female, whom received a pulmonary vein (PV) isolation (PVAI) with linear ablation of the carina lines between the superior and inferior PVs of both the right and left PVs for atrial fibrillation (AF), was admitted to receive a radiofrequency catheter ablation (RFCA) of symptomatic drug-refractory atrial tachycardia (AT). The EnSite^TM analysis by the Advisor^TM HD Grid catheter during the AT could easily detect that the carina between the right superior and inferior PVs exhibited a low voltage area (< 0.5 mV), in addition to the fact that the electrical activation turned around the right PVs in a figure 8, even though mapping was performed during AT. This AT was steadily terminated, after commencing the radiofrequency energy delivery to the carina of the right PVs.

Mid-Term Outcomes of a Modification of Extended Aortic Arch Anastomosis with Pulmonary Artery Banding in Single Ventricle Neonates with Hypoplastic Transverse Arch

PURPOSE

There is less certainty regarding the best strategy for treating neonates with functional single ventricle (SV) and hypoplastic aortic arch. We have applied a modified extended aortic arch anastomosis (EAAA) and main pulmonary artery banding (PAB) as an initial palliation in neonates with transverse arch hypoplasia and assessed the mid-term outcomes.

METHODS

In total, 10 neonates with functional SV and extensive hypoplasia or interruption of the arch underwent a modified EAAA (extended arch anastomosis with a subclavian flap) concomitant with main PAB through a thoracotomy without cardiopulmonary bypass. Patient age and weight ranged from 4 to 14 days and 2.3 to 3.8 kg, respectively.

RESULTS

There were no hospital deaths although there were two late deaths. Gradients across the arch were 0 to 7 mmHg at postoperative day 1 and no arch reoperations were required. Two patients required balloon aortoplasty. Nine underwent bidirectional cavopulmonary shunt and two of them needed concomitant Damus-Kaye-Stansel (DKS) anastomosis. Six have completed Fontan.

CONCLUSION

Our modification of EAAA with main PAB for SV neonates may benefit a certain population with transverse arch hypoplasia as an option to be considered. Patients with the potential for developing outflow obstruction may be best managed with an initial DKS-type palliation.

Gastrointestinal bleeding associated with antithrombotic therapy in the elderly in Japan

BACKGROUND/AIMS

We summarize data of patients with gastrointestinal bleeding (GIB) and discuss the relationship between antithrombotic drug use and age in patients with GIB.

METHODOLOGY

One-hundred and twenty patients with GIB were divided into two groups according to age (=75 years old and <75 years old). The causes and clinical outcome of each group were compared.

RESULTS

Forty-two patients received antithrombotic therapy. The main antithrombotic drugs were low dose aspirin (38 patients), ticlopidine (5 patients) and warfarin (3 patients). Compared with younger GIB patients, elderly patients had more coexisting illness and antithrombotic drugs. In patients taking antithrombotic drugs, upper GIB is more frequent than those not taking antithrombotic drugs (p<0.05) and antithrombotic drugs were the risk for GIB from erosive lesions of the esophagus or stomach. In the lower gastrointestinal tract, there was no difference of incidence related to antithrombotic use. The initial endoscopic hemostasis was performed in 14 patients. Eight varices patients received endoscopic vanding and 6 of 43 gastroduodenal ulcer patients had mechanical clip hemostasis.

CONCLUSIONS

From our findings, antithrombotic drugs were considered to be a risk for GIB. It might be important to prevent or minimize GIB in elderly patients prescribed antithrombotic drugs.

Gastrointestinal bleeding and blood transfusion in the elderly in Japan

BACKGROUND/AIMS

The incidence of gastrointestinal bleeding (GIB) increases with age and blood transfusion is frequently given for the management of GIB. In this report, we summarized our data of the patients with GIB and discussed the relationship between blood transfusion and age in patients with GIB.

METHODOLOGY

The patients were divided into two groups according to age, following elderly (≥75 years old) and younger (<75 years old) group. The causes and clinical outcome (blood transfusions, management) of each group were compared.

RESULTS

One-hundred and twenty patients with GIB were hospitalized (59 men, 61 women) with a mean age of 72.0±15.8 years (range 16-96 years old). Thirty-one patients (25.8%) received blood transfusion. The mean pre-transfusion hemoglobin was 6.4±1.2g/dL (elderly 6.3±1.4, younger 6.6±1.0g/dL) and the mean amount of blood transfusion was 2.8±1.6U (elderly 3.2±1.8, younger 2.3±0.9U). The elderly patients using antithrombotic drugs need greater amounts of blood transfusion than younger patients using antithrombotic drugs. The hemoglobin level of the elder patients without antithrombotic drugs was significantly lower than that of younger patients without antithrombotic drugs.

CONCLUSIONS

Our data suggest that our blood transfusion strategy seems to be in tolerance level with restrictive blood transfusion strategy.

Intraoperative saline injection leak test--a simple method to assess mitral valve repair when a simultaneous aortotomy does not allow pressurization of the left ventricle

We describe a simple, safe and reliable intraoperative saline injection leak test for accomplishing and testing the efficacy of mitral valve repair when a simultaneous aortotomy is present.

[A case of intracardiac repair for anatomically corrected malposition of the great arteries (S, D, L)]

A 5-year-old boy with anatomically corrected malposition of the great arteries (Van Praah's {S, D, L} arrangement type) associated with ventricular septal defect (malalignment conus type) and pulmonary stenosis underwent a biventricular repair. Subpulmonary stenosis was repaired by muscle resection of narrowing muscular subpulmonary conus through the right ventricle. The postoperative catheterization showed that the pressure ratio of right ventricle/left ventricle was 0.4. There was no complication during follow-up period of 6 years.

[A surgical case of supravalvular aortic stenosis with severe hypoplastic ascending aorta (diffuse type) in Williams-Beuren syndrome]

We report a six-year-old boy who underwent ascending aortic reconstruction for supravalvular aortic stenosis of diffuse type associated with Williams-Beuren syndrome. The diagnosis was first made at the age of six months. Because of progressive left ventricular hypertrophy, cardiac catheterization was performed at the age of five years and showed left ventricular pressure of 200 mmHg, the ascending aortic pressure of 202 mmHg, the descending aortic pressure of 115 mmHg, and left ventricular end-diastolic volume of 33.5 ml (90% of normal). Whole ascending aorta except sinus Valsalva was severely hypoplastic, so called diffuse type of supravalvular aortic stenosis. The ascending aorta was only 6.3 mm in diameter, whereas the diameter of the aortic annulus was 20.6 mm. The ascending aortic reconstruction of Doty's type was performed from the aortic root to the distal aortic arch with a equine pericardium reinforced by Dacron velour using selective perfusion to the right bracheocepharic artery, the left common carotid artery and the right femoral artery to avoid circulatory arrest. Postoperative course was uneventful and post operative catheterization revealed left ventricular pressure of 128 mmHg, the ascending aortic pressure of 126 mmHg and the descending aortic pressure of 90 mmHg. Mild residual pressure gradient was probably due to hypoplastic descending aorta. In conclusion, patch aortic reconstruction for ascending aorta under selective cerebral perfusion for a six-year old boy can be performed without postoperative neurological complication.

[Surgical treatment of double outlet left ventricle]

Double outlet left ventricle (DOLV) is an uncommon congenital cardiac defect which was first reported by Sakakibara and associates. We studied anatomical aspects relevant to surgical repair in our 4 cases and additional 28 cases which had been reported on the literatures. The locations of ventricular septal defect (VSD) were subaortic in 20 cases, subpulmonary in 7, doubly-committed in 2 and unknown in 2. The positions of the aorta relative to the pulmonary artery were right or left anterior oblique in 11 cases, right or left side-by-side in 9, right or left posterior oblique in 10 and unknown in 3. The definitive surgery included Rastelli type operation in 18 cases, right ventricular outflow tract repair with closure of VSD in 6, intraventricular conduit repair in 4 and Fontan type operation in 4. In regard to the selection of the procedure, the size of right ventricle, the presence of pulmonary stenosis, the location of VSD and the relationship of the great arteries are very important. Although most of the patients underwent the Rastelli type operation, the right ventricular outflow tract reconstruction or intraventricular conduit repair could be adopted particularly in patients with posterior oblique position of the aorta relative to the pulmonary artery or subpulmonary VSD.

[A successful Konno's operation for subaortic stenosis progressed after total correction of partial atrioventricular septal defect associated with polysplenia]

Konno's operation was successfully performed on a small infant, weighing 3.8 kg. She underwent pulmonary artery banding on the 29th day of life under the diagnosis of partial atrioventricular septal defect with a small left ventricle, associated with polysplenia. Intracardiac repair was subsequently performed on the 45th day of life, which included atrial partition and mitral valvuloplasty. Eleven months after the second operation, wedge resection on the narrow subaortic fibrous lesion was done concomitant with mitral revalvuloplasty. However, repeated echocardiac study disclosed progression of subaortic stenosis. Cardiac catheterization performed at 2 years of age showed the pressure gradinet of 90 mmHg between the aorta and the LV. The aortic annulus and the subaortic lesion measured 10 mm and 4 mm in diameter respectively. Severe subaortic stenosis was created by protrusion of abnormal mitral tissue to the LV outflow, in addition by secondary circumferential fibrous tissue growth and hypertrophy of the ventricular septum. Konno's operation using on 18A Carbomedics valve was chosen for the certain relief of the subaortic stenosis. Although the operation required extensive ventriculotomy and septostomy because of the small aortic annulus, the postoperative course was uneventful. Two months after the operation echocardiography showed good LV function and low RV pressure of about 40 mmHg.

[Repair of D-transposition of the great arteries associated with double aortic arch]

We report a case of D-transposition of the great arteries associated with double aortic arch. An aortic root angiogram revealed that the left-sided aortic arch was anterior and smaller than the right one and the descending thoracic aorta located on the left side of the spine. Balloon atrial septostomy was performed at one day of age. The patient underwent a simultaneous arterial switch procedure and division of the vascular ring at the isthmus of the left aortic arch through a median sternotomy incision at the age of 16 days. There was persistent postoperative difficulty in weaning the patient from the ventilator. Magnetic resonance images showed re-formation of pseudovascular ring by the connective tissue grown around the divided arch. At the age of 23 days, resection of the remnant of left aortic arch including the left subclavian artery and the diverticulum concomitant with vascular suspension procedure was performed through a left lateral thoracotomy. The patient was subsequently extubated without difficulty and was discharged from the hospital. It is though that a vascular suspension procedure and resection of the subclavian artery are necessary to avoid respiratory obstruction when the great arteries are in an anteroposterior position and Lecompte procedure is performed.

[Right atrial flap method for repair of partial anomalous pulmonary venous drainage into the high superior vena cava--case report]

We report an alternative method of repairing partial anomalous pulmonary venous return (PAPVR) wherein anomalous veins drain into the high portion of superior vena cava (SVC). A six year old girl, weighing 19 kg underwent cardiac catheterization for cardiomegaly. The study showed sinus venous defect and pulmonary veins anomalously drained from the right upper and middle lobe into the high SVC. Under cardiopulmonary bypass with aortic and bicaval direct cannulation, a 2-cm-wide pedicled flap made from the middle part of the right atrium (RA), was pulled into the SVC. The atrial flap divided the SVC from the ostium of the uppermost pulmonary vein (PV) to the ASD. This posterior tunnel drained anomalous PV blood into the left atrium. Postoperative echocardiogram and magnetic resonance imaging showed adequate space in the SVC and the PV channel. The patient maintained normal sinus rhythm after surgery. The advantage of this method is to minimize the risk of injuring the sinus node or sinus node artery, and to easily reconstruct both the SVC and PV channel without using prosthetic materials, even in patients with small RA.

[Surgical treatment for tetralogy of Fallot with pulmonary atresia right ventricular outflow tract reconstruction with autologous pulmonary tissue and concomitant extensive pulmonary angioplasty]

Eight consecutive patients with tetralogy of Fallot associated with pulmonary atresia successfully underwent corrective surgery without using an extracardiac conduit at a mean age of 2 years 4 months. Each of these patients had undergone a classical or modified Blalock-Taussig shunt at a mean age of 55 days. In 6 cases, central PA was fully mobilized and pulled forward. An autologous flap was made from the rudimentary PA trunk or right PA, then it was anastomosed to the endocardium of RV infundibulum as a posterior wall of the outflow tract. In 7 cases, concomitant extensive pulmonary angioplasty was performed on stenotic and under-developed lesions which were caused by tissue contraction of the PDA. During follow up period from 11 to 25 months, all patients have remained in good condition without restenosis of the RVOT. The mean pressure ratio of RV over LV measured 0.42 in 5 patients who underwent catheterization after operation. We conclude that these procedures are useful for early corrective surgery of tetralogy of Fallot with pulmonary atresia.

[Intermittent mini-dose vancomycin intravenous administration and closed continuous irrigation technique applied to mediastinitis caused by MRSA following mitral valve replacement]

Mediastinitis caused by MRSA (Methicillin-Resistant Staphylococcus aureus) remains an intractable infection producing high mortality even in these days of advanced chemotherapy. The authors report a case of mediastinitis due to MRSA complicated with acute renal failure following mitral valve replacement. The patient's mediastinum had been thoroughly cleaned with physiological saline solution with 0.2% povidone iodine, and underwent a chemotherapy regimen of mini-dose vancomycin. The patient made favorable progress and recovered completely. Our patient's progress confirmed that when chemotherapy using vancomycin is administered in a patient whose condition is complicated with acute renal failure, closely monitoring the vancomycin serum concentration is essential. Intermittent mini-dose intravenous administration is sufficient to maintain an effective vancomycin serum concentration. In our case, vancomycin serum concentration measured before and at completion of dialysis revealed no appreciable decline.

Left-sided unilateral pulmonary edema in postinfarction ventricular septal rupture

Unilateral pulmonary edema (UPE) is an unusual clinical condition occurring in left heart failure (LHF). Normally, cardiogenic UPE is more pronounced on the right side when no right pulmonary artery obstructive lesion exists. In contrast, we present a rare case of left-sided UPE due to ventricular septal rupture (VSR) complicated by acute myocardial infarction. Although the precise mechanism of unilateral presentation is not clear, such a left-sided unilateral manifestation is extremely rare in LHF. This is believed to be the first reported case of left-sided UPE with postinfarction VSR.