transprosthetic Pressure Gradient after aortic Valve Replacement with Small Sized Prostheses / 대한흉부외과학회지

BACKGROUND: The prognosis after an aortic valve replacment can be affected significantly by the transprosthetic pressure gradient which is determined mainly by the size of the patients body and the prosthesis used. We analyzed the hemodynamic feature of two relatively new prosthese the ATS and the evensized Medtronic-Hall(M-H) valves by measuring the transprosthetic pressure gradient in the cases where small sizes (23mm or smaller) were used. MATERIAL AND METHOD: There were 94 patients who received whom aortic valve replacement with prosthesis smaller than 23 mm from October 1994 to June 1998. In these patients the transprosthetic pressure gradient clalculated from the pressure half time during postoperative Dopper echocardiographic examination was compared between the prostheses of different sizes. The body surface area of each patient was also taken into consideration. RESULT: The mean pressure gradient and body surface area in each group were 21.7+/-10.2 mmHg and 1.52+/-0.14m2 in ATS 19mm 11.4+/-6.5 mmHg and 1,57+/-0.20m2 in M-H 20mm 15.2+/-6.3 mmHg and 1.54+/-0.13m2 in ATS 21mm 9.3+/-2.5 mmHg and 1.63 +/-0.14m2 in M-H 22 mm and 12.9+/-5.3 mmHg and 1.69+/-0.13m2 in ATS 23mm. CONCLUSIONS: The 19mm ATS prosthesis showed significant trasprosthetic pressure gradient which is similar to the values previously reported with other bileaflet prosthesesm Close follow-up was needed in terms of exercise capacity and change in left ventiricular geometry. In patients with small aortic valve annulus the 20mm M-H valve is recomendable as an alternative to 19mm bileaflet valves because it has less pressure gradient with similar outer diameter.

Complicatons and Residual Defects After Correction of Noncomplicated Ventricular Septal Defect / 대한흉부외과학회지

BACKGROUND: The purpose of this study is to review the clinical course after the correction of noncomplicated ventricular septal defect and to analyze the morbidity and risk factors of postoperative complications and evaluate residual defect during the follow-up period. MATERIAL AND METHOD: From September 1994 to June 1998 24 patients(median age 10 months) underwent surgery under the diagnosis of ventricular septal defect. We made a retrospective review of the clinical records including the operation notes critical care unit records echocardiography results and the follow-up records. RESULT: There was no early mortality nd late mortality. There was no postoperative complete conduction block. Respiratory complication was the most common complication. The body weight age type of ventricular septal defect associated anomalies and operative procedure were not related to the incidence of complications. residual ventricular septal defects aortic valve regurgitation and tricuspid valve regurgitation were insignificant in postoperative hemodynamics, CONCLUSIONS: Correction of the noncomplicated ventricular septal defect was done without mortality and complete heart block. Aggressive preoperative medical treatment and early surgical treatment may decrease postoperative complications. Postoperative residual shunt and tricuspid regurgitation were not problematic during the follow-up.

Partial Left Ventriculectomy in the Pediatric Patient with Dilated Cardiomyopathy / 대한흉부외과학회지

Heart transplantation was planned for a 10-year old boy who had dilated cardiomyopathy with severe congestive heart failure and had been on dopamine for 1month. However, partial left ventriculectomy and mitral annuloplasty were performed instead, because there was no donor heart of the adequate size and the symptoms were aggravated. The clinical symptoms were markedly improved after the surgery. Comparing the postoperative echocardiographic results with the preoperative results, there were remarkable changes in the left ventricular ejection fraction(preoperative LV EF 17% to postoperative 3 months 29%, 6 months 35%, 1 year 36%) and the left ventricular end-diastolic dimension(preoperative 72 mm to postoperative 3 months 59 mm, 6 months 61 mm, 1 year 61 mm). Partial left ventriculectomy and mitral annuloplasty reduced the cardiac loading in the dilated cardiomyopathy. Partial left ventriculectomy and mitral annuloplasty may be considered as one of the alternative surgical metho s to carry over until a heart transplantation can be performed, especially for children.

Risk Factors of Neurologic Complications After Coronary Artery Bypass Grafting / 대한흉부외과학회지

BACKGROUND: As the early outcome after coronary artery bypass grafting(CABG) has been stabilized, neurologic complication has now become one of the most important morbidity. The aim of this study was to find out the risk factors associated with the neurologic complications after CABG. MATERIAL AND METHOD: In 351 patients who underwent CABG, the incidence and features of neurologic complications, with associated perioperative risk factors, were retrospectively reviewed. Neurologic complication was defined as a new cerebral infarction confirmed by postoperative neurologic examination and radiologic studies, or delayed recovery of consciousness and orientation for more than 24 hours after the operation. RESULT: Neurologic complications occurred in 18 patients(5.1%), of these nine(2.6%) were diagnosed as having new cerebral infarctions(stroke). Stroke was manifested as motor paralysis in four patients, mental retardation or orientation abnormality in four, and brain death in one. Statistical analysis revealed the following variables as significant risk factors for neurologic complications by both univariate and multivariate analyses: cardiopulmonary bypass longer than 180 minutes, atheroma of the ascending aorta, carotid artery stenosis detected by Duplex sonography, and past history of cerebrovascular accident or transient ischemic attack. Age over 65 years, aortic calcification detected by simple X-ray, and intraoperative myocardial infarction were significant risk factors by univariate analysis only. Neither the severity of carotid artery stenosis nor technical modifications such as cannulation of the aortic arch or single clamp technique, which were expected to affect the inciden e of neurologic complications, had significant relationship with the incidence. CONCLUSION: This study confirmed the strong association between neurologic complications after CABG and atherosclerosis of the arterial system. Therefore, to minimize the incidence of neurologic complications, systematic evaluation focused on atheroscleroti.

Minimal Skin Incision with Full Sternotomy for Congenital Heart Surgery / 대한흉부외과학회지

BACKGROUND: Although there have been few reports about minimal skin incision for the repair of congenital heart lesions, minimizing an unsightly scar is a particularly important factor in growing children. We have adopted a technique that permits standard full sternotomy, conventional open chest cardiopulmonary bypass, aortic cross-clamping, left atrial vent, and antegrade cardioplegia with minimal surgical scar. MATERIAL AND METHOD: With minimal skin incision and full sternotomy, 40 patients with congenital heart disease underwent open heart surgery from April 1997 through September 1997. Defects repaired included 30 ventricular septal defects, 4 atrial septal defects, and 1 sinus Valsalva aneurysm in 35 children(M:F=17: 18), and 3 Atrial septal defects, 1 ventricular septal defect, and 1 partial atrioventricular septal defect in 5 adults(M:F=1:4). Midline skin incision was performed from the second intercostal space to 1 or 2 cm above the xiphoid process. For full sternotomy, we used the ordinary sternal saw in sternal body, and a special saw in manubrium under the skin flap. During sternal retraction, surgical field was obtained by using two retractors in a crossed direction. RESULT: The proportion of the skin incision length to the sternal length was 63.1+/-3.9%(5.2~11cm, mean 7.3cm) in children, and 55.0+/-3.5%(10~13.5cm, mean 12cm) in adults. In every case, the aortic and venous cannulations could be done through the sternal incision without additional femoral cannulation. There was no hospital death, wound infection, skin necrosis, hematoma formation, or bleeding complication. CONCLUSION: We conclude that minimal skin incision with full sternotomy can be a safe and effective alternative method for the repair of congenital heart diseases in children and adults.

Computerized Quantative Analysis of Cornary Angiogram in Patients without Coronary Pathology / 대한흉부외과학회지

In the preoperative evaluation before coronary artery bypass surgery, review of the coronary arteriogram is the most important step. Expected "normal" lumen diameter at a given coronary anatomic location is a basis for quantative estimation of coronary disease severity that could be more useful than the traditional "percent stenosis". The distribution and number of major coronary artery branches are determinants of number of bypass grafts needed. We reviewed the coronary artery anatomy in 174 adult patients who revealed no coronary pathology in angiographic studies done from September 1994 to June 1996. Quantative analysis was done in all cases by a single person using a Computerized System (Arripro 35(r)). The results were follows; 1) The mean diametre of left main coronary artery was 4.45 mm (range 2.74~6.72). The pattern of branching was bifurcation in 67.24%, trifurcation in 28.74% and quadrifurcation in 4.02% of the patients. 2) The mean diametre of left anterior descending artery was 3.17 mm (range 2.10~5.85), 2.79 (range 1.55~5.59) and 2.17 mm (range 1.37~3.81) in the proximal, mid, and the distal portions, respectively. The number of diagonal branches of left anterior artery was from one to four (mode=2). 3) The mean diametre of proximal and distal left circumflex artery were 3.17mm (range 1.74~4.89) and 2.19 mm (range 1.21~4.46). The number of obtuse marginal branches of left circumflex artery is from one to six (mode 2). 4) The mean diametre of proximal and distal right coronary artery, the posterior descending artery and the largest posterolateral branch were mean 3.51 mm (range 2.07~5.67), 2.09 mm (range 1.42~3.60), 2.09 mm (range 1.02~3.60) and 2.30 mm (range 1.39~4.39). 5) The right coronary artery dominant was 163 cases (93.68%) of the total 174 cases. 6) The large significant acute marginal artery was visualized in more than half of the people.