Complete Closure Of Defect Research Articles

Plicated Patch Repair for Acquired Gerbode Defect Involving the Tricuspid Valve

Gerbode's defect, a left ventricular-to-right atrial communication, with involvement of the tricuspid valve acquired after bacterial endocarditis can be challenging to repair. We report a modified technique for a shunt closure and reconstruction of the tricuspid valve using a plicated bovine pericardial patch. Combining such a repair with a left ventricular patch resulted in a complete defect closure and competent tricuspid valve without regurgitation.

A randomized clinical trial of autologous platelet‐rich plasma in the treatment of mandibular degree II furcation defects

A combined technique using a platelet-rich plasma (PRP)/bovine porous bone mineral/guided tissue regeneration membrane was found to be an effective modality for the treatment of mandibular grade II furcation defects. To elucidate the role played by each component, the present randomized, double-blind study is designed to evaluate the effectiveness of autologous PRP alone in the treatment of mandibular degree II furcation defects compared with open flap debridement (OFD). Using a split-mouth design, 40 mandibular degree II furcation defects were treated either with autologous PRP or OFD. Plaque index, sulcus bleeding index, vertical probing depth, relative vertical and horizontal clinical attachment level and gingival marginal level were recorded at baseline and 6 months post-operatively. Vertical and horizontal defect depths were also recorded using spiral computed tomography. A statistically significant difference was observed in all the clinical and radiographic parameters at the sites treated with PRP as compared with those with OFD. However, all the furcation defects retained their degree II status. Despite a significant improvement, lack of complete closure of furcation defects implies a limited role of autologous PRP as a regenerative material in the treatment of furcation defects, necessitating further long-term studies.

Transcatheter Closure of Secundum Atrial Septal Defects in the Elderly

Background and Objectives: With the exception of bicuspid aortic valves, atrial septal defects (ASDs) are the most common congenital heart lesions found in adults. A mortality and morbidity benefit has clearly been demonstrated in the treatment of this lesion in younger patients. However, the benefits of ASD closure are less well defined in the elderly. We report our experience with transcatheter ASD closure and detail its impact on functional status and right ventricular remodeling as indicators of right heart failure in patients greater than 60 years of age. Subjects and Methods: Fifty-five patients (median age 70 years) underwent ASD closure at a single center during an eight-year period. Data were collected and analyzed retrospectively. Results: Transcatheter closure was successful in all patients. No major complications occurred during the periprocedural or follow-up periods. Complete defect closure was documented in 97% of patients during follow-up. All patients improved by at least one New York Heart Association (NYHA) functional class. Following ASD closure, no patient was in NYHA III or IV. The median right-ventricular end-diastolic diameter decreased from 39 mm to 26.6 mm (p<0.001). Conclusion: Atrial septal defect closure is safe and effective in elderly patients. Our data and prior published data consistently demonstrate that even patients greater than 60 years of age experience improvement in functional status and right ventricular remodeling. Therefore, patient age should not influence the decision of whether an ASD should be closed. (Korean Circ J 2009;39:47-51)

蝶形骨洞に進展したクモ膜嚢胞例

Arachnoid cysts are commom intracranial lesions; however, their extension to the paranasal sinus is rare. Here we report a case of arachnoid cyst extending to the sphenoid sinus. Imaging examinations indicated an epidermoid cyst. We then performed endoscopic transsphenoidal surgery for partial resection of the cyst or formation of a drainage route. Opening the cyst wall resulted in a massive CSF leak, indicating an arachnoid cyst. Management of CSF leakage requires complete closure of the defect in the skull base using a fat graft and a pedicle mucosal flap elevated from the nasal septum. An arachnoid cyst should be included in the differential diagnosis of intracranial cystic lesions extending to the paranasal sinuses.

The cuticular purse string suture: a modified purse string suture for the partial closure of round postoperative wounds

The purse string suture can be used to provide primary closure for small skin defects or as a partial closure for larger round wounds. The size of the defect is reduced secondary to the tension placed on the suture, which uniformly advances the skin from the entire periphery of the wound. We reviewed retrospectively the features of 98 consecutive patients for whom a total of 100 cuticular purse string sutures were used to partially close their postoperative surgical defects. The location and types of the tumors removed were also summarized. Postoperative wounds were created following Mohs' micrographic excision of nonmelanoma skin cancer (basal cell carcinoma, 44; squamous cell carcinoma, 25), wide local excision of melanoma (29), or conservative excision of benign cutaneous neoplasms (two). The incidence of purse string suture for partial closure of each tumor was 4.1% for basal cell carcinoma, 7.3% for squamous cell carcinoma, and 46.3% for melanoma. The tumors were equally distributed on the trunk, head and neck, and extremities; however, purse string closures for basal cell carcinomas were more frequent on the trunk, head, and neck, relative to squamous cell carcinomas and melanomas, which were more common on the extremities. Concurrent medical problems and/or the use of an agent with anticoagulant or antiplatelet effects were noted in more than 50% of patients. Absorbable material of thicker diameter was most frequently used for the suture, and the postoperative wound area decreased by 6-90% (mean, 60%) following purse string partial closure. The suture was usually removed after 3-4 weeks. Postoperative complications occurred in six patients: allergic contact dermatitis in two, wound infection in two, exuberant granulation tissue in one, and hypertrophic scar in one. All of the wounds healed completely with either a round or linear scar. The cuticular purse string suture is a rapid and simple procedure that provides complete or partial closure of round skin defects and excellent long-term cosmetic and functional results. This closure provides uniform tension to the wound, enhances hemostasis at the tissue edge, and significantly decreases the size of the defect. Partial wound closure with the purse string suture may be advantageous following the local excision of melanoma, either as definitive surgical wound management or as a temporary partial wound closure prior to subsequent complete repair of the surgical defect. The purse string suture is also useful following nonmelanoma skin cancer removal in patients who insist on maintaining an active lifestyle in the immediate postoperative period, who are receiving one or more systemic anticoagulant and/or antiplatelet agents, and who have large surgical wounds that would require either a skin graft or a local cutaneous flap in order to close the postoperative defect.

The purse‐string suture revisited: a useful technique for the closure of cutaneous surgical wounds

The purse-string suture provides complete or partial closure of round postoperative skin defects. It is a rapid and simple procedure to perform. Tension placed on the suture uniformly advances the skin from the entire periphery of the wound, resulting in a significant reduction of the defect size and enhancement of hemostasis at the wound edge. The history, modifications of the technique, advantages, and potential complications of the purse-string suture are reviewed. It is not only useful following the removal of nonmelanoma skin cancer but also after the local excision of melanoma. In addition, this technique is especially suitable for the repair of round surgical wounds for patients who are unable to modify their active lifestyles during the week following surgery, individuals concurrently being treated with anticoagulants, antiplatelet agents or both, and people with extensive postoperative defects that would otherwise require either a skin graft or a large cutaneous flap. Typically, the site of the surgical wound following partial or complete closure with the purse-string suture demonstrates excellent long-term cosmetic and functional results.

Closure of Rabbit Calvarial Critical-Sized Defects Using Protective Composite Allogeneic and Alloplastic Bone Substitutes

This study evaluated the repair of critical-sized cranial vault defects in thirty New Zealand white rabbits using various allogeneic and alloplastic bone substitutes designed to provide mechanical protection to the brain as well as osteoinductivity. The strategies employed included demineralized bone matrix (DBM), a putty used in combination with a rigid resorbable plating system as a protective covering and calcium phosphate cement (CPC) combined with native partially purified bone morphogenetic protein (BMP). Bilateral critical-sized defects measuring 15 mm in diameter were created in the parietal bones of 30 adult male New Zealand white rabbits. They were divided into three groups with ten animals in each. Group 1 had one defect left unfilled as a control while autogenous bone was placed in the defect on the other side. In Group 2 a rigid resorbable copolymer membrane, Lactosorb (Lorenz Surgical, Jacksonville, Florida), was placed over both defects to cover them and protect the underlying tissues. The pericranial aspect of one defect was left unfilled while the other defect was filled with DBM putty. Group 3 had a CPC, Mimix (Lorenz Surgical, Jacksonville, Florida), placed into one of the defects while the defect on the other side was filled with the same CPC in combination with BMP in a concentration of 25 mg/mL. Bone healing was assessed clinically, radiographically, and histomorphometrically. All unfilled controlled defects, the defects covered with the resorbable Lactosorb membrane and those filled with calcium phosphate cement alone, healed with a fibrous scar. Defects reconstructed with DBM putty in combination with the resorbable Lactosorb membrane and calcium phosphate in combination with BMP healed with bone bridging the entire defect. This was obvious radiographically where the defects appeared completely filled with a dense radiopaque tissue. Histological analysis demonstrated that specimens where DBM putty was used in combination with the resorbable Lactosorb membrane had 67.7% new bone fill at 6 weeks and 84.0% at 12 weeks. Resorption of DBM particles was evidenced by the presence of osteoclastic activity and by the significant decrease in the size of the demineralized bone particles. In the calcium phosphate groups where BMP was added to the bioimplant there was 45.8% new bone formation at 12 weeks. The utilization of a composite consisting of DBM with resorbable Lactosorb membrane or a composite of calcium phosphate cement composite with BMP promoted complete closure of critical-sized calvarial defects in New Zealand white rabbits with viable new bone at 12 weeks. The complete bone bridging observed with these composites suggests that they could be used to enhance the protection of intracranial contents following craniofacial surgical procedures.

A Novel Endoscopic Technique to Close Large Post EMR Defects Using a Double Ring and Clips

Background and Aims: Even though EMR is proven to be a safe procedure when used to remove nonpolypoid colorectal lesions, the risks of hemorrhage and perforation increase with lesions larger than 20 mm. To prevent such complications, we have previously reported a technique to close large mucosal defect produced after an EMR using the endoloop snare and metallic clip suture method. This procedure, however, requires the use of a two-channel colonoscope, which is not always available in every endoscopy unit. We have recently developed a novel and simple technique for complete closure of large mucosal defects using a stainless double-ring device that can be used to close a large defect using a conventional one-channel colonoscope. Methods: A conventional metallic clip (Boston Scientific Co., MA, USA) is placed through one hole of this double loop shape device to the periphery of the large post-resection mucosal defect. Another clip is inserted through the remaining hole of the device and clipped in the normal mucosa approximating the margins of the defect and thus obtaining a complete closure. To prevent the closure from becoming loose, a third metallic clip is placed to reinforce the suture. Results: From August 2005 to November 2005, we performed post EMR defect closure of 6 large colorectal lesions in 6 patients (mean age: 61.8 ± 4.4 years) using the previously described technique. Lesions average size was 14.7 ± 2.2 mm (12-18 mm). Locations were ascending colon (3), descending (2) and sigmoid (1). Macroscopic type was large flat (5) and sessile (1). Histopathology of the resected specimens revealed intramucosal neoplasia (5) and submucosal invasive cancer (1). All post EMR defects were successfully closed and no complications were observed. Conclusions: With this technique, large colorectal lesions, which would be otherwise be removed surgically due to the high risk of complications, can be safely resected by EMR enabling the procedure to become a day surgery.

Self–fabricated fenestrated Amplatzer occluders for transcatheter closure of atrial septal defect in patients with left ventricular restriction: midterm results

To avoid left ventricular failure after transcatheter closure of atrial septal defects in elderly patients with restrictive left ventricular physiology, partial occlusion by fenestrated devices may be an option. If complete defect closure is not possible in these patients, significant reduction of left to right shunting usually results in clinical benefit. We report two patients in whom deterioration of left ventricular function could be avoided by implantation of self-fabricated fenestrated Amplatzer Septal Occluders (ASO) in patients with ongoing restrictive left ventricular physiology. We describe technical preparation of the standard occluder, the specific implantation technique, and the initial and the intermediate term results up to 24 months.

Kinetic Study of Early Regenerative Effects of RGTA11, a Heparan Sulfate Mimetic, in Rat Craniotomy Defects

We previously reported that RGTA, a synthetic heparan sulfate mimetic, induces almost complete closure of craniotomy defects one month after surgery in adult rats. RGTA-treated wounds showed features suggesting unusual cell and matrix interactions reminiscent of developmental events. As healing success or failure is determined shortly after wounding, we examined early events in RGTA-treated wounds. Collagen plasters soaked in a solution of RGTA11 (1.5 Microg per piece) or saline (control) were implanted in rat craniotomy defects. Seven control and seven treated rats were killed daily from days 1 to 7 after surgery. The lesions and adjacent tissues were sampled and processed for morphometry. A layer of type III collagen along the dura mater (DM) thickened up to day 5 in RGTA-treated wounds (p < 0.05 vs day 1), but became thinner in control wounds. Alkaline phosphatase-positive osteoprogenitor cells were detected on day 1 in this layer. Their number increased, and they migrated toward the mid-sagittal sinus and to connective tissue adjacent to the sinus, where they aggregated and differentiated into osteoblasts, forming bone nodules on day 6. These features were not seen in control wounds. Angiogenesis was significantly enhanced in RGTA-treated wounds, especially near the sinus. In vitro, bovine bone endothelial (BBE) cell proliferation was inhibited by RGTA11 in a concentration-dependent manner. In contrast, RGTA11 strongly enhanced the effect of fibroblast growth factor-2 on BBE cell proliferation. These results show that RGTA11, possibly by interacting with heparin-binding growth factors, elicits vascular reactions accompanying the recruitment of a large pool of committed osteoprogenitors from the DM. The DM and the sinus appear to be important centers of organization for craniotomy defect healing. RGTA probably creates an environment that starts a program of directing healing towards bone formation and defect closure.

Remmert′s flap (RF): Refined method of tongue reconstruction

Objectives: To describe the clinical research program, surgical technique, anatomical as well as histological findings and postoperative functional results in patients in whom a new neurovascular infrahyoid muscle flap (Remmert′s flap, RF) was the essential part of tongue reconstruction. Methods: RF originates from the infrahyoid muscles and was dissected during the neck dissection procedure as a uni- or bilateral flap. RF was indicated in 71 patients (14 female, 57 male). The youngest was 21, the oldest 71 years of age (mean, 52.8; median, 53; STD, 9.9 years). The majority of our patients had advanced stages of disease (T1, 1; T2, 24; T3, 28; T4, 18). Results: Tumor resection required a transmandibular (55), transpharyngeal (5), transoral (4), or a pull through (7) approach. The defect to be closed was situated in the oral tongue (3), tongue base (28), or both (40 patients). Minimal morbidity resulted in 20 patients in whom a complete defect closure was achieved with the RF. Combined procedures of defect closure (radial forarm flap with or without free fibula transfer, 37; jejunal graft, 9; upper arm flap, 4; iliac crest, 1) were indicated for the majority of patients. Speech and swallowing was restored to an acceptable rate. Preliminary experimental and histological studies revealed that innervation of RF via the deep cervical ansa is essential to prevent unintentional atrophy of the flap. Conclusions: RF serves as a reliable tool for tongue reconstruction with a minimal tendency to shrink. In combination with free vascular tissue transfer the flap is ideal to close larger defects.

MRI evaluation of patellar tendon defect after harvesting its central third

Purpose: the purpose of this study was to evaluate defect width of patellar tendon after harvest for anterior cruciate ligament reconstruction. Materials and methods: we performed MRI at various time interval after graft harvest (2–96 months) on 28 patients who had had reconstruction of the anterior cruciate ligament using mid-third patellar tendon. T1 and T2 weighted axial images were obtained to assess donor site defect of the patellar tendon. Measurement of the defect width was performed at the level of menisci on the axial images. The patients were divided into two groups according to the time interval between operation and imaging. The defect width of patients with short time interval (2–12 months) was compared to the defect width of patients with long time interval (12–96 months). Results: the average defect width of patients with short time interval was 6.4 mm and it was 2.2 mm for the patients with long time interval. Decreased defect width was obtained from MRI images in the patients with long time interval. Closed donor site defect was detected in 1 out of 14 patients with short time interval and 6 out of 14 patients with long time interval. Discussion and conclusion: these results show that there is no complete closure of donor site defect up to 1 year. However, it seems to be nearly complete closure of patellar tendon defect in the long time period.

Synergistic effect of gelatin microspheres incorporating TGF-β1 and a physical barrier for fibrous tissue infiltration on skull bone formation

The objective of this study is to examine whether or not bone formation at a skull bone defect induced by gelatin microspheres incorporating transforming growth factor (TGF)-β1 is promoted by prevention of fibrous tissues into the defect. The 6-mm diameter bone defect of rabbit skulls was applied with gelatin microspheres incorporating TGF-β1 or free TGF-β1 and physically covered by a barrier membrane. When the bone formation at the defect was assessed 6 weeks postoperatively, combinational application of gelatin microspheres incorporating 0.1 μg of TGF-β1 with the barrier membrane induced bone formation at the skull defect, in marked contrast to that of 0.1 μg of free TGF-β1 and empty gelatin microspheres. Complete defect closure was histologically observed by the newly formed bone tissue. Without the barrier membrane, gelatin microspheres incorporating TGF-β1 were less effective in inducing bone formation, whereas free TGF-β1 and empty gelatin microspheres were ineffective. The skull defect was occupied by fibrous tissue infiltrated in place of bone tissue. The bone mineral density at the skull defect applied with gelatin microspheres incorporating TGF-β1 plus the membrane was significantly higher than that of gelatin microspheres incorporating TGF-β1 alone. The present data indicated that physical protection from the soft tissue infiltration enabled gelatin microspheres incorporating TGF-β1 to synergistically enhance the osteoinductive ability at the skull defect.

Complete atrioventricular septal defect associated with tetralogy of fallot: surgical indications and results.

Complete atrioventricular septal defect (AVSD) associated with tetralogy of Fallot is a rare condition that still has problems in the postoperative period. The authors report their surgical experiences over the past 10 years. Nine children underwent total correction. The defect was repaired by the 2-patch technique and the ATrioventricular valve was reconstructed by suturing the cleft and annuloplasty. A transannular right ventricular outflow patch was used in 5 patients. All patients had Down syndrome and a free-floating superior bridging lEAflet. One patient died from cardiac failure. Although there was no reoperation or death in the late postoperative periods, mild mitral regurgitation occurred in 4 patients and there was moderate or severe pulmonary regurgitation in 2 patients. All survivors currently have no critical symptoms in their daily lives. With the standard of patient selection used, the optimal body weight was around 8 kg and PA index was 200 or more. Right ventriculotomy provided a better view for complete closure of the ventricular septal defect (VSD). In order to avoid re-regurgitation of the atrioventricular valve, the 2-patch technique is the most suitable procedure for total repair.

The ASDOS Device: Technique and Guidelines for Clinical Use

The atrial septal defect occlusion system (ASDOS) is one of the recently developed systems for nonsurgical closure of interatrial communications. The ASDOS occluder consists of two self‐opening umbrellas made of nitinol wire frame and polyurethane membrane. The unique ASDOS technique provides: (1) an “over‐the‐wire” individual umbrella manipulation within the atria; (2) several positioning and repositioning attempts; (3) simultaneous selective left atriography; (4) adjustable joining together of both umbrellas depending on the atrial septal wall thickness; (5) septal tissue immobilization in patients with septal aneurysm; and (6) controlled “over‐the‐wire” retrieval through the same 11Fr introducing venous sheath. The experimental studies showed a complete device incorporation after 3 months. The clinical experience accumulated during a 4‐year period confirmed the safety and efficacy of this system. The complete defect closure was achieved in two thirds of patients immediately after the procedure. A significant residual shunt remained in a small number of treated patients. Complications included: (1) thrombus formation around the device in some patients; (2) perforation of the atrial wall in patients with inappropriately implanted devices; and (3) an infectious endocarditis. Device frame fracture was observed in 14% of patients during a follow‐up of 250 patient‐years. There have been no late device dislodgment and no injury to the atrioventricular valves after ASDOS closure. The ratio of the diameter of the implanted umbrellas to the short atrial septal diameter ranged between 1.4‐2.2. Since it can immobilize the septum, the ASDOS proved to be especially indicated for closure of defects with aneurysm of the residual septum. In patients with a patent foramen ovale (PFO), the adjustable ASDOS umbrellas keep the valve of the oval fossa tightly closed to the secundum septum. Our experience confirms the feasibility of catheter techniques for treatment of patients with centrally situated secundum ASD or PFO.

Transcatheter occlusion of secundum atrial septal defects with the self-centering Amplatzer Septal Occluder

A new approach to transcatheter occlusion of secundum atrial septal defects uses the self-centering and repositionable `Amplatzer Septal Occluder'. This report presents our initial clinical experiences with this device, made from a 0.005-inch Nitinol mesh and polyester fabric. During a 2-year period, 98 patients (median age 6.3 years, range 1–43 years, median weight 22 kg, range 10–82 kg) with secundum atrial septal defects were evaluated for transcatheter closure of the defect using the Amplatzer Septal Occluder. The diameters of the defects measured by transesophageal echocardiography ranged from 5 to 23 mm (median 12 mm) and the stretched diameters measured by balloon catheter ranged from 7 to 28 mm (median 15 mm). Established criteria for interventional treatment were met in 98 patients and defect implantation was successful in 88 of them (89.8%). Median fluoroscopy time was 15 min (range 7–64 min) and the total procedure time was 90 min (range 55–16 min). After 24 h, colorflow Doppler examination showed complete defect closure in 72 of the 88 (82%) patients. Complete closure was demonstrated in 55 (96.5%) of 57 patients followed for at least 3 months after implantation. In all 10 patients followed for more than 1 year, no residual shunts were found. No clinical complication, fracture of the device wires, or embolization of the device has occurred.

Initial clinical results with the Amplatzer septal occluder--a self-centering double disc for occlusion of atrial septal defects

In recent years many different systems for transcatheter closure of an atrial septal defect (ASD) have been developed and tested. However, all systems presently available have some special disadvantages. The recently introduced Amplatzer Septal Occluder (ASO), though, appears promising. It is a self-expanding and self-centering double disc made from a Nitinol mesh, which is tightly woven to give mechanical strength. Both discs are separated by a connecting cylindrical portion. Its diameter may be chosen, so that it corresponds to that of the ASD. Discs of polyester patches are sewn into the retention discs as well as into the cylindrical portion of the device in order to augment thrombogenicity. After measuring the diameter of the ASD with a balloon, an appropriate ASO is selected and advanced into the left atrium through a 7 or 8 French sheath. Then the distal disc and part of the connecting cylindrical portion is developed in the left atrium and pulled against the atrial septum, so that the cylindrical portion is occluding the ASD. Thereafter, proximal disc is deployed and the delivery cable disconnected. As long as the cable is connected to the device repositioning is easily achieved by pulling the device back into the sheath. Within a time period of 4 months in 29 out of 31 patients (median age: 12.1 years, median weight: 45.0 kg) complete closure of the ASD with a mean diameter of 11.0 mm (6-20 mm) was achieved without complications, the average fluoroscopy time being 8.3 min (2.9-21.5 min). Mean Qp:Qs was 1.5 (0.9-2.2). During a mean follow-up period of 2.1 months post implantation fixed seating of the ASO without residual shunt, arrhythmias, thrombembolic events and impairment of A-V valves was observed in all patients. The Amplatzer septal occluder allows quick, safe, and complete closure of atrial septal defects without complications if one adheres to strict implantation criteria. For a final judgement, however, long-term follow-up studies are necessary.

Clinical course of isolated ventricular septal defect: an Indian experience.

To define the clinical course of ventricular septal defect, 410 consecutive patients with isolated ventricular septal defect were evaluated over a period of 13 years. Their age ranged from 12 days to 24 years at the time of first visit to the hospital. Patients with less than 2 years follow-up period were excluded. One hundred and fifty seven patients were one year of age or less. The left to right shunt size remained the same in 52.4% of cases. In 34.4% the shunt size decreased, with complete closure of ventricular septal defect in 8.8%. Closure of ventricular septal defect was observed even in patients who had initially presented with large left to right flow, and congestive heart failure in infancy. Right ventricular outflow tract obstruction developed in 8.5% of patients usually between 2 and 10 years of age. Murmur of aortic regurgitation appeared in 8.9% on follow-up. Infective endocarditis developed in 6 cases. The unfortunate complication of Eisemenger's complex was seen in 3 patients; they had not returned for follow up for a long period of time. Hence, our data show that the left to right shunt across the ventricular septal defect decreases in about one-third of patients. However, a regular follow up is essential to prevent development of Eisenmenger's complex and for early detection of other complications like aortic regurgitation and right ventricular outflow tract obstruction.

Staphylococcal infective endocarditis occurring 12 years following complete patch closure of a ventricular septal defect

Staphylococcal infective endocarditis occurring 12 years following complete patch closure of a ventricular septal defect

Spontaneous closure of ventricular septal defect in a case of double outlet right ventricle.

A 5 year old child, previously diagnosed as having tetralogy of Fallot, was admitted to hospital in severe congestive heart failure. The electrocardiogram showed left anterior hemiblock and incomplete right bundle-branch block, neither of which was previously present. The child died in intractable congestive heart failure and the necropsy showed a double outlet right ventricle with complete spontaneous closure of the subaortic ventricular septal defect by fibrous tissue. The possible mechanism involved in the production of this unusual complication of double outlet right ventricle is discussed, together with an explanation for the electrocardiographic changes.