Aortic Valve Replacement in the Era of Transcatheter Aortic Valve Implantation: Current Status in Korea

Background@#In the era of transcatheter aortic valve implantation, this study was conducted to investigate the current trend of aortic valve procedures in Korea and to evaluate the early and mid-term outcomes of isolated surgical aortic valve replacement (SAVR) using bioprosthetic valves in contemporary Korea. @*Methods@#Contemporary outcomes of isolated bioprosthetic SAVR in Korea were analyzed using the datasets on a multicenter basis. Patients who underwent isolated SAVR using bioprostheses from June 2015 to May 2019 were included, and those with concomitant cardiac procedures, SAVR with mechanical valve, or SAVR for infective endocarditis were excluded. A total of 456 patients from 4 large-volume centers were enrolled in this study.Median follow-up duration was 43.4 months. Early postoperative outcomes, mid-term clinical outcomes, and echocardiographic outcomes were evaluated. @*Results@#Mean age of the patients was 73.1 ± 7.3 years, and EuroSCORE II was 2.23 ± 2.09. The cardiopulmonary bypass time and aortic cross-clamp times were median 106 and 76 minutes, respectively. SAVR was performed with full median sternotomy (81.8%), right thoracotomy (14.7%), or partial sternotomy (3.5%). Operative mortality was 1.8%. The incidences of stroke and permanent pacemaker implantation were 1.1% and 1.1%, respectively. Paravalvular regurgitation ≥ mild was detected in 2.6% of the patients. Cumulative incidence of all-cause mortality at 5 years was 13.0%. Cumulative incidences of cardiovascular mortality and bioprosthetic valve dysfunction at 5 years were 7.6% and 6.8%, respectively. @*Conclusion@#The most recent data for isolated SAVR using bioprostheses in Korea resulted in excellent early and mid-term outcomes in a multicenter study.

Changes in Prevalence and Treatment Pattern of Benign Prostatic Hyperplasia in Korea / 대한배뇨장애요실금학회지

Purpose@#Benign prostatic hyperplasia (BPH) is associated with lower urinary tract symptoms and negatively affects the quality of life. We aimed to investigate the treatment pattern of BPH in South Korea. @*Methods@#Information on treatment modalities and diagnoses of BPH was obtained from the Health Insurance Review and Assessment Service-Aged Patient Sample. Data on BPH patients aged ≥60 years from 2012 to 2016 were obtained. We surveyed the treatment pattern of BPH, including the types of drugs used and surgeries performed, according to the type of institution. @*Results@#In this study, 18,260–24,657 BPH patients treated between 2012 and 2016 were included. The number of patients showed an increasing pattern, and drug therapy was the major treatment method used for BPH (98.77%). Moreover, the pattern of increased pharmacotherapy use for BPH was reinforced by the increasing number of patients. Prescription of α-blockers only was dominant in this cohort (45.7%). Transurethral resection of the prostate (TURP) was the most commonly used surgical treatment for BPH (53.6%), but it showed a decreasing pattern over time. In contrast, holmium laser enucleation of the prostate (HoLEP) showed an increase from 19.4% to 39.7%. @*Conclusions@#The most common treatment for BPH was drug therapy, predominantly only α-blocker therapy. The surgical treatment trend has changed from TURP to HoLEP.

Outcomes of emergency endovascular versus open repair for abdominal aortic aneurysm rupture

Purpose@#Ruptured abdominal aortic aneurysm (rAAA) is one of the most common aortic emergencies in vascular surgery and is associated with high operative mortality and morbidity rates despite recent treatment advances. We evaluated operative mortality risks for the outcomes of emergency endovascular aneurysm repair (eEVAR) vs. open repair in rAAA. @*Methods@#Twenty patients underwent eEVAR (n = 12) or open repair (n = 8) for rAAA between 2016 and 2020. We adopted the EVAR first strategy since 2018. Primary endpoints included in-hospital mortality and 1-year survival. The outcome variables were analyzed with Fisher exact, Mann-Whitney test, and linear by linear association. The Kaplan-Meier method was used to estimate survival. @*Results@#There were 13 males (65.0%) and the median age of the study cohort was 78.0 years (range, 49–88 years). Inhospital mortality occurred in 7 patients (35.0%); 5 (50.0%) in the early period and 2 (20.0%) in the later period of this series. According to the procedure type, 4 (50.0%) and 3 (25.0%) in-hospital mortalities occurred in the open repair and eEVAR patients, respectively. In 6 patients (50.0%), eEVAR was performed on unfavorable anatomy. The 1-year survival of eEVAR vs. open repair group was 75% ± 12.5% and 50% ± 17.7%, respectively. On univariate analysis, preoperative highrisk indices, postoperative acute renal failure requiring dialysis, pulmonary complications, and prolonged mechanical ventilation were associated with higher operative mortality. @*Conclusion@#The current data showed relatively superior outcomes with eEVAR vs. open repair for rAAA, even in some patients with unfavorable anatomy supporting the feasibility, efficacy, and safety of EVAR first strategy.

Outcomes of emergency endovascular versus open repair for abdominal aortic aneurysm rupture

Purpose@#Ruptured abdominal aortic aneurysm (rAAA) is one of the most common aortic emergencies in vascular surgery and is associated with high operative mortality and morbidity rates despite recent treatment advances. We evaluated operative mortality risks for the outcomes of emergency endovascular aneurysm repair (eEVAR) vs. open repair in rAAA. @*Methods@#Twenty patients underwent eEVAR (n = 12) or open repair (n = 8) for rAAA between 2016 and 2020. We adopted the EVAR first strategy since 2018. Primary endpoints included in-hospital mortality and 1-year survival. The outcome variables were analyzed with Fisher exact, Mann-Whitney test, and linear by linear association. The Kaplan-Meier method was used to estimate survival. @*Results@#There were 13 males (65.0%) and the median age of the study cohort was 78.0 years (range, 49–88 years). Inhospital mortality occurred in 7 patients (35.0%); 5 (50.0%) in the early period and 2 (20.0%) in the later period of this series. According to the procedure type, 4 (50.0%) and 3 (25.0%) in-hospital mortalities occurred in the open repair and eEVAR patients, respectively. In 6 patients (50.0%), eEVAR was performed on unfavorable anatomy. The 1-year survival of eEVAR vs. open repair group was 75% ± 12.5% and 50% ± 17.7%, respectively. On univariate analysis, preoperative highrisk indices, postoperative acute renal failure requiring dialysis, pulmonary complications, and prolonged mechanical ventilation were associated with higher operative mortality. @*Conclusion@#The current data showed relatively superior outcomes with eEVAR vs. open repair for rAAA, even in some patients with unfavorable anatomy supporting the feasibility, efficacy, and safety of EVAR first strategy.

Large Focal Extrapleural Hematoma of Chest Wall: A Case Report

Although hemothorax and pneumothorax are common complications seen in rib fractures, focal extrapleural hematoma is quite rare. We report a 63-year-old female patient that developed large focal extrapleural hematoma after falling off a second floor veranda. The patient had sustained 3, 4, 5th costal cartilage rib fractures and a sternum fracture. She had developed suspected empyema with loculations with small amount of hemothorax. She underwent a planned early decortication/adhesiolysis by video assisted thoracoscopic surgery at the 12th post-trauma day due to failed drainage. Unexpectedly, she had no adhesions or any significant retained hematoma mimicking a mass, but was found with the focal extrapleural chest wall hematoma. She was discharged on postoperative 46th day for other reasons and is doing fine today.

Bilateral Chylothorax Due to Blunt Spine Hyperextension Injury: A Case Report

Bilateral chylothorax due to blunt trauma is extremely rare. We report a 74-year-old patient that developed delayed bilateral chylothorax after falling off a ladder. The patient had a simple 12th rib fracture and T12 lamina fracture. All other findings seemed normal. He was sent home and on the 5th day visited our emergency center at Halla Hospital with symptoms of dyspnea and lower back pain. Computer tomography of his chest presented massive fluid collection in his right pleural cavity and moderate amounts in his left pleural cavity with 12th rib fracture and T11-12 intervertebral space widening with bilateral facet fractures. Chest tubes were placed bilaterally and chylothorax through both chest tubes was discovered. Conservative treatment for 2 weeks failed, and thus, thoracic duct ligation was done by video assisted thoracoscopic surgery. Thoracic duct embolization was not an option. Postoperatively, the patient is now doing well and happy with the results. Early surgical treatment must be considered in the old patient, whom large amounts of chylothorax are present.

Guidelines for Transcatheter Aortic Valve Replacement in Korea: Past Obstacles and Future Perspectives

BACKGROUND: Analyses of the efficacy and safety of transcatheter aortic valve replacement (TAVR) in most countries have been based on outcomes obtained in accordance with national practice guidelines and monitoring protocols. The purpose of this study is to share our experience regarding the process for establishing guidelines and monitoring protocols for the use of TAVR in Korea, in the hopes that it may be helpful to others undergoing a similar process in their own country. METHODS: The Korean guidelines for TAVR were established on June 1, 2015 in through a tri-party agreement involving the Department of Health and Welfare, the Korean Society of Thoracic and Cardiovascular Surgery and the Korean Society of Cardiology. We agreed to monitor the guidelines transparently and to exchange opinions regarding amendments or continuation of its contents after 3 years of monitoring. RESULTS: The monitoring meetings were not held as regularly as agreed, and monitoring was also made difficult by insufficient and incomplete data. Nevertheless, during the meetings, measures to improve the monitoring process were discussed, and accordingly, an agreement was made to continue the monitoring process, with the aim of completing data collection by 2018. CONCLUSION: Compliance with guidelines is critical for assessing the efficacy and safety of TAVR. Moreover, the TAVR monitoring process must be properly conducted for an accurate evaluation to be made. Any country planning to introduce TAVR may encounter difficulties with regards to the optimal initiation strategy and subsequent monitoring. Nevertheless, continued efforts should be made to persuade the government and the corresponding medical societies to facilitate the optimal application of TAVR.

Short- and Long-Term Results of Triple Valve Surgery: A Single Center Experience

Triple valve surgery is usually complex and carries a reported operative mortality of 13% and 10-yr survival of 61%. We examined surgical results based on our hospital's experience. A total of 160 consecutive patients underwent triple valve surgery from 1990 to 2006. The most common aortic and mitral valve disease was rheumatic disease (82%). The most common tricuspid valve disease was functional regurgitation (80%). Seventy-four percent of the patients were in New York Heart Association (NYHA) class III and IV. Univariate and multivariable analyses were performed to identify predictors of early and late survival. Operative mortality was 6.9% (n=11). Univariate factors associated with mortality included old age, preoperative renal failure, postoperative renal failure, pulmonary complications, and stroke. Of them, postoperative renal failure and stroke were associated with mortality on multivariable analysis. Otherwise, neither tricuspid valve replacement nor reoperation were statistically associated with late mortality. Survival at 5 and 10 yr was 87% and 84%, respectively. Ninety-two percent of the patients were in NYHA class I and II at their most recent follow-up. Ten-year freedom from prosthetic valve endocarditis was 97%; from anticoagulation-related hemorrhage, 82%; from thromboembolism, 89%; and from reoperation, 84%. Postoperative renal failure and stroke were significantly related with operative mortality. Triple valve surgery, regardless of reoperation and tricuspid valve replacement, results in acceptable long-term survival.

Hemothorax in an Uncontrolled Anticoagulated Patient: Fight or Flight?: A Case Report / 대한구급학회지

Hemothorax in a patient on anticoagulant therapy for atrial fibrillation after blunt trauma is not an uncommon event. However, massive hemothorax in such a patient with an extremely uncontrolled and high international normalized ratio (INR) may pose a serious dilemma. We report a case of a patient under anticoagulant therapy for atrial fibrillation who underwent an emergent thoracotomy for massive hemothorax with an INR of 9.57.

In Vitro Effects of Nitroglycerin, Nicardipine, Verapamil, and Papaverine on Rabbit Brachial and Celiac Arterial Tone / 대한흉부외과학회지

BACKGROUND: Vasoconstrictor-induced reduction in arterial graft diameter can cause significant flow deprivation. The aim of this study was to evaluate the effect of vasodilator pretreatment on vasoconstrictor-induced blood vessel spasm in vitro. MATERIAL AND METHOD: Rabbit brachial arteries (BA) and celiac arteries (CA) were cut into rings (3~4 mm) and suspended with a force displacement transducer (TSD 125C(R), Biopac Inc. USA) in a tissue bath filled with 5 mL modified Krebs solution bubbled with 5% CO2 and 95% O2 at 38degrees C. The rings were contracted with vasoconstrictors, and the developed tension changes were considered control values. The rings were then pretreated with 30micrometer nitroglycerin, nicardipine, verapamil, and papaverine, respectively, for 40 minutes and rinsed with the physiologic buffered salt solution three times every 15 min. The vasoconstrictor-induced tension changes after the previous procedure were considered experimental values. Data are expressed as the percentage tension induced by vasoconstrictors before and after pretreatment with vasodilators. RESULT: Nicardipine depressed vasoconstriction induced by norepinephrine, angiotensin II (AII), and U46619 in both the BA and the CA more significantly than did nitroglycerin (p<0.01) and verapamil (p<0.05). Verapamil depressed vasoconstriction induced by 5-hydroxytryptamine (5HT), AII, and U46619 in the BA and by 5HT in the CA more significantly than did nitroglycerin (p<0.01). CONCLUSION: These findings suggest that both nicardipine and verapamil effectively depressed vasoconstrictor action. Nicardipine is thought to be more effective than verapamil for the prevention of vasoconstrictor action.

The Clinical Application and Results of Palliative Damus-Kaye-Stansel Procedure / 대한흉부외과학회지

BACKGROUND: The Damus-Kaye-Stansel (DKS) procedure is a proximal MPA-ascending aorta anastomosis used to relieve systemic ventricular outflow tract obstructions (SVOTO) and pulmonary hypertension. The purpose of this study was to review the indications and outcomes of the DKS procedure, including the DKS pathway and semilunar valve function. MATERIAL AND METHOD: A retrospective review of 28 patients who underwent a DKS procedure between May 1994 and April 2006 was performed. The median age at operation was 5.3 months (13 days~38.1 months) and body weight was 5.0 kg (2.9~13.5 kg). Preoperative pressure gradients were 25.3+/-15.7 mmHg (10~60 mmHg). Eighteen patients underwent a preliminary pulmonary artery banding as an initial palliation. Preoperative main diagnoses were double outlet right ventricle in 9 patients, double inlet left ventricle with ventriculoarterial discordance in 6, another functional univentricular heart in 5, Criss-cross heart in 4, complete atrioventricular septal defect in 3, and hypoplastic left heart variant in 1. DKS techniques included end-to-side anastomosis with patch augmentation in 14 patients, classical end-to-side anastomosis in 6, Lamberti method (double-barrel) in 3, and others in 5. The bidirectional cavopulmonary shunt and Fontan procedure were concomitantly performed in 6 and 2 patients, respectively. RESULT: There were 4 hospital deaths (14.3%), and 3 late deaths (12.5%) with a follow-up duration of 62.7+/-38.9 months (3.3~128.1 months). Kaplan-Meier estimated actuarial survival was 71.9%+/-9.3% at 10 years. Multivariate analysis showed right ventricle type single ventricle (hazard ratio=13.960, p=0.004) and the DKS procedure as initial operation (hazard ratio=6.767, p=0.042) as significant mortality risk factors. Four patients underwent staged biventricular repair and 13 received Fontan completion. No SVOTO was detected after the procedure by either cardiac catheterization or echocardiography except in one patient. There was no semiulnar valve regurgitation (>Gr II) or semilunar valve-related reoperation, but one patient (3.6%) who underwent classical end-to-side anastomosis needed reoperation for pulmonary artery stenosis caused by compression of the enlarged DKS pathway. The freedom from reoperation for the DKS pathway and semilunar valve was 87.5% at 10 years after operation. CONCLUSION: The DKS procedure can improve the management of SVOTO, and facilitate the selected patients who are high risk for biventricular repair just after birth to undergo successful staged biventricular repair. Preliminary pulmonary artery banding is a safe and effective procedure that improves the likelihood of successful DKS by decreasing pulmonary vascular resistance. The long-term outcome of the DKS procedure for semilunar valve function, DKS pathway, and relief of SVOTO is satisfactory.

Small Aortic Annulus in Aortic Valve Replacement; Comparison between Aortic Annular Enlargement Group and Patient-prosthesis Mismatch Group / 대한흉부외과학회지

BACKGROUND: The effect of patient-prosthesis mismatch (PPM) on the clinical outcome following aortic valve replacement (AVR) remains controversial. This study compared the surgical outcomes of AVR between patients with a patient-prosthesis mismatch and those having undergone an aortic annular enlargement. MATERIAL AND METHOD: Six hundred and twenty seven adult patients, who underwent AVR with stented bioprosthetic or mechanical valves, between January 1996 and February 2006, were evaluated. PPM was defined as an indexed effective orifice area (iEOA) < or =0.85 cm2/m2, and severe if the iEOA < or =0.65 cm2/m2. PPM was present in 103 (16.4%, PPM group) patients, and severe in 11 (1.8%, SPPM group). During the period of the study, 21 patients underwent an AVR with annular enlargement (AE group). RESULT: The mean iEOA of the AE group was larger than that of the PPM group (0.95 vs. 0.76 cm2/m2, p=0.00). The AE group had longer CPB, ACC and operation times than the PPM group, and showed a tendency toward higher operative mortality (14.3% vs. 2.9%, p=0.06). The SPPM group had higher AV pressure gradients (peak/mean) than the AE group (72/45 mmHg vs. 38/25 mmHg, p=0.02/0.06) and suffered more AV related events (AV reoperation or severe aortic stenosis)(45.5% vs. 9.5%, p=0.03). LV masses were not regressed in the patients who experienced an AV related event. CONCLUSION: During AVR in patients with a small aortic annulus, annular enlargement should be carefully applied taking into account the high risk of operative mortality due to annular enlargement and co-morbidities of patients. Aortic annular enlargement; however, should be considered as an alternative method in patients expected to have a severe PPM after an AVR.

Low Cardiac Output Syndrome Caused by a Coronary Artery Spasm following CABG / 대한흉부외과학회지

Coronary artery spasm immediately after the coronary artery bypass graft (CABG) surgery is rare but it can cause sudden and severe hypotension or a ventricular arrhythmia. We report a case of low cardiac output syndrome caused by a right coronary artery spasm following CABG that did not show any significant stenotic lesions on preoperative coronary angiography.

Clinical Analysis of Repeated Heart Valve Replacement / 대한흉부외과학회지

BACKGROUND: There are two choices for heart valve replacement-the use of a tissue valve and the use of a mechanical valve. Using a tissue valve, additional surgery will be problematic due to valve degeneration. If the risk of additional surgery could be reduced, the tissue valve could be more widely used. Therefore, we analyzed the risk factors and mortality of patients undergoing repeated heart valve replacement and primary replacement. MATERIAL AND METHOD: We analyzed 25 consecutive patients who underwent repeated heart valve replacement and 158 patients who underwent primary heart valve replacement among 239 patients that underwent heart vale replacement in our hospital from January 1995 to December 2004. RESULT: There were no differences in age, sex, and preoperative ejection fraction between the repeated valve replacement group of patients and the primary valve replacement group of patients. In the repeated valve replacement group, the previously used artificial valves were 3 mechanical valves and 23 tissue valves. One of these cases had simultaneous replacement of the tricuspid and aortic valve with tissue valves. The mean duration after a previous operation was 92 months for the use of a mechanical valve and 160 months for the use of a tissue valve. The mean cardiopulmonary bypass time and aortic cross clamp time were 152 minutes and 108 minutes, respectively, for the repeated valve replacement group of patients and 130 minutes and 89 minutes, respectively, for the primary valve replacement group of patients. These results were statistically significant. The use of an intra aortic balloon pump (IABP) was required for 2 cases (8%) in the repeated valve replacement group of patients and 6 cases (3.8%) in the primary valve replacement group of patients. An operative death occurred in one case (4%) in the repeated valve replacement group of patients and occurred in nine cases (5.1%) in the primary valve replacement group of patients. Among postoperative complications, the need for mechanical ventilation over 48 hours was different between the two groups. The mean follow up period after surgery was 6.5+/-3.2 years. The 5-year survival of patients in the repeated valve replacement group was 74% and the 5-year survival of patients in the primary valve replacement group was 95%. CONCLUSION: The risk was slightly increased, but there was little difference in mortality between the repeated and primary heart valve replacement group of patients. Therefore, it is necessary to reconsider the issue of avoiding the use of a tissue valve due to the risk of additional surgery, and it is encouraged to use the tissue valve selectively, which has several advantages over the use of a mechanical valve. In the case of a repeated replacement, however, the mortality rate was high for a patient whose preoperative status was not poor. A proper as sessment of cardiac function and patient status is required after the primary valve replacement. Subsequently, a secondary replacement could then be considered.

Angiographic Results of Radial Artery Grafts that are Used for Myocardial Revascularization / 대한흉부외과학회지

BACKGROUND: The radial artery is gaining widespread acceptance as complementary arterial conduits for surgical myocardial revascularization, but there have been limited reports about its angiographic patency compared with that of internal thoracic artery or saphenous vein. We tried to evaluate angiographic patency of radial artery graft and to compare that of radial artery and other grafts with retrospective manner. MATERIAL AND METHOD: From January 2001 to June 2006, totally 132 patients (male 92, female 40) who underwent coronary artery bypass graft using radial artery were re-admitted to our hospital for follow up angiographic examination. Mean age was 58.2+8.87 and mean follow up duration was 32 month (2~110 month). Off pump and on pump bypass surgery were performed 74 and 58 patients respectively. Along with radial artery, left internal thoracic arteries were used in 57 cases, concomitant left internal thoracic artery and saphenous veins were used in 47 cases and bilateral internal thoracic arteries were used in 20 cases. RESULT: Totally 412 distal anastomosis were performed and 376 anastomosis remained patent (91.2%). Left internal thoracic artery showed the most excellent patency in all of the conduits (98.5%). Radial artery graft patency was 90.8% (169/186). There was no statistical difference of the patency by conduit between on-pump and off-pump group. But radial artery showed more higher patency rate (98/110, 89%) in the severe stenotic lesion that preoperatively revealed more than 90% stenosis than in the lesser severe (<90%) stenotic lesion (60/76, 78%)(p<0.005). Radial artery conduit represented the worst result when it was grafted in the right coronary system. But when it was positioned in the left heart especially diagonal or obtuse marginal area, patency was comparable with left internal thoracic artery. CONCLUSION: Radial artery graft showed good midterm patency when it was used in the severe stenotic lesion more than 90% and left coronary system. But great notice should be taken when it is grafted in the right coronary system or less severe stenotic lesion.

Short Term and Midterm Surgical Results for Infective Endocarditis: Does Wide Debridement and Reconstruction Affect the Post Operative Mortality and Morbidity? / 대한흉부외과학회지

BACKGROUND: We present here the early and midterm surgical results for infective endocarditis and we especially focus on the effect of aggressive reconstruction or root implantation after wide debridement. MATERIAL AND METHOD: Between January 1995 and Jun 2006, we enrolled 79 adult infective endocarditis patients who underwent surgical treatment. There were 63 and 16 native and prosthetic valve endocarditis cases, respectively. They included 27 cases of culture negative endocarditis. With performing valve replacement or repair, 28 of the patient underwent a more aggressive surgical option, for example, aortic root replacement or reconstruction, or heart base reconstruction etc. RESULT: There were statistical relationships between the in-hospital mortality and staphylococcal infection, urgent-based operation and operation during the active phase of endocarditis. Wide debridement and aggressive reconstruction were not related to either the post operative mortality or the early morbidity. Culture negative endocarditis was not related to the postoperative mortality and morbidity. CONCLUSION: Physicians must pay attention to patients' medical treatment during the preoperative period of the infective endocarditis. If surgery is considered for treating infective endocarditis, it should be performed before the downhill course of the disease so that the surgical outcome is improved. Wide debridement and more aggressive reconstruction are also warranted.

Proximal Coronary Artery Stenosis after Direct Coronary Artery Ostial Perfusion : Report of 3 Cases / 대한흉부외과학회지

Proximal coronary artery stenosis after direct coronary artery ostial perfusion is an infrequent but life-threatening complication. We had been experienced 3 cases of proximal coronary artery stenosis related to direct ostial perfusion since September, 2000. And now we report the cases.

Myocardial Perfusion after Transmyocardial Mechanical Revascularization in Rat Heart Transplant Model, Acute Model / 대한흉부외과학회지

BACKGROUND: Transmyocardial revascularization (TMR) in end stage ischemic heart disease results in variable clinical responses. We investigated the acute effect of early reperfusion and the angiogenesis after formation of the transmyocardial channel in a transplanted rat heart model with acute myocardial infarction. MATERIAL AND METHOD: In the 30 transplanted hearts we induced acute myocardial infarction by ligating the proximal left coronary artery and inserted a porous 22G intravenous cannula into the left ventricle. After ten minutes of reperfusion, we removed the cannula. At every stage, we recorded the heart rate, QRS size, and left coronary arterial blood flow using the electrocardiogram and Doppler. One week later the rats were sacrificed and evaluated for the patency of intramyocardial channels and the angiogenesis. RESULT: The heart rates after ligation and after cannula insertion were 239.1+/-61.7, 235.8+/-58.0 bpm respectively, and they were statistically significantly slower than that of before ligation, 277.6+/-40.3 bpm (p=0.017, p=0.007 respectively). QRS sizes before ligation, after ligation, and after cannula insertion were 3.6+/-3.3 mm, 2.8+/-3.3 mm, and 2.4+/-2.2 mm, respectively, and there was no significant difference in the three groups. Doppler findings after ligation showed that average peak and mean values of coronary perfusion were significantly decreased from 2.11+/-0.17 kHz, 1.25+/-0.22 kHz to 0.83+/-0.15 kHz, 0.38+/-0.11 kHz (p<0.05 respectively). After insertion of the porous cannula, the average peak and mean values of coronary perfusion were 0.61+/-0.05 kHz and 0.33+/-0.05 kHz respectively, but there was no statistically significant change compared to values after ligation. In all cases except one, pathologic findings showed no patent channels in the acute stage, however, one case showed the angiogenesis. CONCLUSION: We confirmed that TMR in a rat heart transplant model did not show blood flow through the channel in the acute stage. However, reperfusion effect in some cases had a potential for angiogenesis.

Colchicine Derivatives Allows Prolonged Survival of Cardiac Allograft in the Rat / 대한흉부외과학회지

BACKGROUND: Colchicine with its immunosupressive properties has been used with beneficial effects in autoimmune disease, such as Gout, etc. Whether colchicine, by virtue of the above property, could attenuate the process of cardiac allograft rejection in the rats is investigated in this report. MATERIAL AND METHOD: We compared the untreated group (Control, n=6), Cyclosporin A group (10 mg/kg, daily, n=20), and Colchicine derivative group (Colchicine 40 microgram/kg, n=20) of cardiac allografts in the rats. RESULT: In the untreated control group (n=6), all of 6 rats showed rejection within 3 weeks after cardiac allograft. In the cyclosporin A group (n=20), cyclosporin A (10 mg daily oral dose) was administered at a 10 mg daily oral dose and promoted long-term survival (over 100 days). The cyclosporin A group had one mortality at the 18th post-operative day due to infection. Furthermore, in the Colchicine derivatives group (n=20) with a daily IP (Intra Peritoneum) dose (40 ug/kg/day), we observed long-term survival.(>100 days), except for one rat that died of an anesthetic problem (respiratory failure) at the 9th post-operative day. CONCLUSION: Experiments have also been performed to evaluate whether the effect of colchicine derivatives allowed prolonged survival of cardiac allografts compared with the cyclosporin A administration group in the rats.