• Journal of Chest Surgery
• /
• v.31 no.4
• /
• pp.339-345
• /
• 1998

Arrhythmias are common after cardiac surgery and are multifactorial. Intravenous magnesium administration reduces the frequency of ventricular arrhythmias in patient with symptomatic heart failure or acute myocardial infarction. This study was designed to evaluate the role of magnesium in preventing PVCs(premature ventricular contractions) occurred frequently after coronary artery bypass graft(CABG). 50 consecutive patients were prospectively entered into a randomized trial to determine the efficacy of postoperative magnesium therapy on the incidence of cardiac arrhythmias after elective coronary artery bypass graft. The patients underwent coronary angiography, echocardiography, electrocardiography and clinical laboratory study preoperatively. Continuous electrocardiographic monitoring was done and magnesium level was checked 0, 3, 6, 12, 18, 24, 36, 48, 60 and 72 hours postoperatively. Study group of 25 patients were given 4g of magnesium continuously over the first 24 hours and then 2g/24hours from 25 to 72 hours. The clinical characteristics of both groups were similar(p<0.05). The preoperative mean serum magnesium concentration was similar in both study group, 1.59mg/dl and control group, 1.71mg/dl. The mean postoperative serum magnesium concentration in study group elevated significantly over postoperative 12hours through 36hours(p<0.05). The postoperative mean serum magnesium concentration in control group declined and remained significantly depressed over immediate postoperation through 72hours. The mean serum magnesium concentration was significantly greater in the study group compared with the control group over postoperative 3hours through 72hours(p<0.05). There was a significant decrease in the incidence of arrhythmias such as PVCs(p<0.01) which might jeopardize hemodynamics. There were no recognized adverse effects of magnesium Administration. In conclusion, prophylactic magnesium administration seems to lessen the incidence and severity of rrhythmias after coponary artery bypass graft.

• Journal of Chest Surgery
• /
• v.38 no.10 s.255
• /
• pp.680-684
• /
• 2005

Background: With the increasing age of the population, coronary artery bypass grafting in the elderly patients is becoming common. Off-pump coronary artery bypass grafting (OPCAB) has been proven to be less morbidity and to facilitate early recovery. The elderly patients may have benefits by avoiding the adverse effects of the cardiopulmonary bypass. The purpose of this study is to evaluate our results of OPCAB in elderly patients. Material and Method: A retrospective chart review was carried out for 12 patients aged over 80 years who underwent isolated OPCAB from January 2001 and March 2004. Data were collected risk factors for disease, extent of coronary disease, and in-hospital outcomes. Postoperative graft patiency was evaluated in 9 patients by multi-slice computed tomography. Result: Eleven patients had triple vessel disease or left main disease. Four patients were suffered from preoperative CVA, and 4 patients had chronic obstructive pulmonary disease. Two patients had myocardial infarction (MI), among them 1 patient was suffered from pulmonary edema after preoperative MI. There was no perioperative death, perioperative MI, and no ventricular arrhythmia. Also there was no perioperative stroke and renal failure. But there was one deep sternal infection who recovered by treating of muscle flap. Atrial fibrillation was newly developed in 1 patient, but was well controlled by medication. Mean intubation time was $15.9\pm4.4(8\~20hrs)$ hrs and mean ICU stay was $2.9\pm0.8(2\~4 days)$ days. Mean hospital day was $21.6\pm14.3(13\~56 days)$ days. Postoperative mean CK-MS was $11.3\pm14.1\;ng/mL$. Early postoperative graft patency rate was $100\%(24/24)$. Follow-up was completed in all patients. In this time, there was no patients with angina or death. Conclusion: The results of this study suggest that OPCAB reduces morbidity and favors hospital outcomes. Therefore, OPCAB is safe, reasonable and might be preferable operative strategy in elderly patients.

• Journal of Chest Surgery
• /
• v.36 no.2
• /
• pp.73-78
• /
• 2003

The Fontan operation has undergone a number of major modifications and clinical results have been improving over time. Nevertheless, during the follow-up period, life-threatening complications develop and affect the long-term outcomes. Surgical interventions for these complications are needed and are increasing. Material and Method: From April 1988 to January 2000, 16 patients underwent reoperations for complications after Fontan operation. The mean age at reoperation was 8.8 :-5.5 years. Initial Fontan operations were atriopulmonary connections in 8 and total cavopulmonary connections in 8. Total cavopulmonary connections were accomplished with intracardiac lateral tunnel in 5 and extracardiac epicardial lateral tunnel in 3. Five patients had variable sized fenestrations. The reasons for reoperations included residual shunt in 6, pulmonary venous obstruction in 3, atrial flutter in 3, atrioventricular valve regurgitation in 2, Fontan pathway stenosis in 1, and protein-losing enteropathy in 1 Result: There were 3 early and late deaths respectively Patients who had residual shunts underwent primary closure of shunt site (n=2), atrial reseptation for separation between systemic and pulmonary vein (n=2), conversion to lateral tunnel (n=1), and conversion to one and a half ventricular repair (n=1). Four patients who had stenotic lesion of pulmonary vein or Fontan pathway underwent widening of the lesion (n=3) and left pneumonectomy (n=1) In cases of atrial flutter, conversion to lateral tunnel after revision of atriopulmonary connections was performed (n=3). For the atrioventricular valve regurgitation (n=2), we performed a replacement with mechanical valve. In one patient who had developed protein-losing enteropathy, aorto-pulmonary collateral arteries were obliterated via thoracotomy. Cryoablation was performed concomitantly in 4 patients as an additional treatment modality of atrial arrhythmia. Conclusion: Complications after Fontan operation are difficult to manage and have a considerable morbidity and mortality. However, more accurate understanding of Fontan physiology and technical advancement increased the possibility of treatment for such complications as well as Fontan operation itself. Appropriate surgical treatment for these patients relieved the symptoms and improved the functional class, Although the results were not satisfactory enough in all patients.

• Journal of Chest Surgery
• /
• v.38 no.2 s.247
• /
• pp.123-131
• /
• 2005

Background: The number of elderly patients undergoing coronary artery bypass grafting (CABG) is increasing. Elderly patients are at increased risk for a variety of perioperative complications and mortality. We identified determinants of operative complications and mortality in elderly patients undergoing CABG. Material and Method: Between January 1995 and July 2003, 91 patients older than 75 years underwent isolated CABG at Asan Medical Center. There were 67 men and 24 women with mean age of $77.0\pm2.4$ years. Thirty clinical or hemodynamic variables hypothesized as predictors of operative mortality were evaluated. Result: CABG was performed under emergency conditions in 5 patients. The internal thoracic artery was used in 85 patients and 10 patients received both internal thoracic arteries. The mean number of distal anastomosis was 3.7 per patient. Operative mortality was $3.3\%$. Twenty-two patients had at least one major postoperative complication. Low cardiac output syndrome was the most common complication, followed by reoperation for bleeding, pulmonary dysfunction, perioperative myocardial infarction, stroke, acute renal failure, ventricular arrhythmia, upper gastrointestinal bleeding, infection, and delayed sternal closure. None were the predictors of mortality. Renal failure, peripheral vascular disease, emergency operation, recent myocardial infarction, congestive heart failure, New York Heart Association (HYHA) class III or IV, Canadian Cardiovascular Society (CCS) angina scale III or IV, and low left ventricle ejection fraction below $40\%$ were univariate predictors of overall complications. Actuarial probability of survival was $94.9\%,\;89.8\%,\;and\;83.5\%$ at postoperative 1, 3 and 5 years respectively. During the follow-up period $93.3\%$ of patients were in NYHA class I, or II and $91.1\%$ were free from angina. Conclusion: Although operative complication is increased, CABG can be performed with an acceptable operative mortality and excellent late results in patients older than 75 years.

• Journal of Chest Surgery
• /
• v.41 no.3
• /
• pp.329-334
• /
• 2008

Background: Percutaneous cardiopulmonary support. (PCPS) has the potential to rescue patients in cardiogenic shock who might otherwise die. PCPS has been a therapeutic option in a variety of the clinical settings such as for patients with myocardial Infarction, high-risk coronary intervention and postcardiotomy cardiogenic shock, and the PCPS device is easy to install. We report our early experience with PCPS as a life saving procedure in cardiogenic shock patients due to acute myocardial infarction. Material and Method: From January 2005 to December 2006, eight patients in cardiogenic shock with acute myocardial infarction underwent PCPS using the CAPIOX emergency bypass system($EBS^{(R)}$, Terumo, Tokyo, Japan). Uptake cannulae were inserted deep into the femoral vein up to the right atrium and return cannulae were inserted into the femoral artery with Seldinger techniques using 20 and 16-French cannulae, respectively. Simultaneously, autopriming was performed at the $EBS^{(R)}$ circuit. The $EBS^{(R)}$ flow rate was maintained between $2.5{\sim}3.0L/min/m^2$ and anticoagulation was performed using intravenous heparin with an ACT level above 200 seconds. Result: The mean age of patients was $61.1{\pm}14.2$ years (range, 39 to 77 years). Three patients were under control of the $EBS^{(R)}$ before percutaneous coronary intervention (PCI), three patients were under control of the $EBS^{(R)}$ during PCI, one patient was under control of the $EBS^{(R)}$ after PCI, and one patient was under control of the $EBS^{(R)}$ after coronary bypass surgery. The mean support time was $47.5{\pm}27.9$ hours (range, 8 to 76 hours). Five patients (62.5%) could be weaned from the $EBS^{(R)}$ after $53.6{\pm}27.2$ hours. (range, 12 to 68 hours) of support. All of the patients who could successfully be weaned from support were discharged from the hospital. There were three complications: one case of gastrointestinal bleeding and two cases of acute renal failure. Two of the three mortality cases were under cardiac arrest before $EBS^{(R)}$ support, and one patient had an intractable ventricular arrhythmia during the support. All of the discharged patients are still surviving at $16.8{\pm}3.1$ months (range, 12 to 20 months) of follow-up. Conclusion: The use of $EBS^{(R)}$ for cardiogenic shock caused by an acute myocardial infarction could rescue patients who might otherwise have died. Successfully recovered patients after $EBS^{(R)}$ treatment have survived without severe complications. More experience and additional clinical investigations are necessary to elucidate the proper installation timing and management protocol of the $EBS^{(R)}$ in the future.

• Journal of Chest Surgery
• /
• v.31 no.3
• /
• pp.233-241
• /
• 1998

To define the risk factors affecting the early major morbidity and mortality after multiple- valve operations, the preoperative, intraoperative and postoperative informations were retrospectively collected on 124 consecutive patients undergoing a multiple-valve operation between October 1985 and July 1996 at the department of Thoracic and Cardiovascular Surgery of Pusan Paik Hospital. The study population consists of 53 men and 71 women whose mean age was 37.9$\pm$11.5(mean$\pm$SD) years. Using the New York Heart Association(NYHA) classification, 41 patients(33.1%) were in functional class II, 60(48.4%) in class III, and 20(16.1%) in class IV preoperatively. Seven patients(5.6%) had undergone previous cardiac operations. Atrial fibrillations were present in 76 patients(61.3%), a history of cerebral embolism in 5(4.0%), and left atrial thrombus in 13(10.5%). The overall early mortality rate and postoperative morbidity was 8.1% and 21.8% respectively. Among the 124 cases of multiple-valve operation, there were 57(46.0%) of combined mitral valve replacement(MVR) and aortic valve replacement(AVR), 48(38.7%) of combined MVR and tricuspid annuloplasty(TVA), 12(9.7%) of combined MVR, AVR and TVA, 3(2.4%) of combined MVR and aortic valvuloplasty, 2(1.6%) of combined MVR and tricuspid valve replacement, and others. The patients were classified according to the postoperative outcomes; Group A(27 cases) included the patients who had early death or major morbidity such as low cardiac output syndrome, mediastinitis, cardiac rupture, ventricular arrhythmia, sepsis, and others; Group B(97 cases) included the patients who had the good postoperative outcomes. The patients were also classified into group of early death and survivor. In comparison of group A and group B, there were significant differences in aortic cross-clamping time(ACT, group A:153.4$\pm$42.4 minutes, group B:134.0$\pm$43.7 minutes, p=0.042), total bypass time(TBT, group A:187.4$\pm$65.5 minutes, group B:158.1$\pm$50.6 minutes, p=0.038), and NYHA functional class(I:33.3%, II:9.7%, III:20%, IV:50%, p=0.004). In comparison of early death(n=10) and survivor(n=114), there were significant differences in age(early death:45.2$\pm$8.7 years, survivor:37.2$\pm$11.6 years, p=0.036), sex(female:12.7%, male:1.9%, p=0.043), ACT(early death:167.1$\pm$38.4 minutes, survivor:135.7$\pm$43.7 minutes, p=0.030), and NYHA functional class(I:0%, II:4.9%, III:1.7%, IV:35%, p=0.001). In conclusion, the early major morbidity and mortality were influenced by the preoperative clinical status and therefore the earlier surgical intervention should be recommended whenever possible. Also, improved methods of myocardial protection and operative techniques may reduce the risk in patients with multiple-valve operation.

• Journal of Chest Surgery
• /
• v.35 no.9
• /
• pp.643-652
• /
• 2002

As the prevalence of coronay artery disease is increasing, the surgical treatment has been universalized and operative outcome has been improved. We analyzed the short and mid-term results of 292 CABGs performed in Kangdong Sacred Heart Hospital. Material and Method: From June 1994 to December 2001, 292 patients underwent coronary artery bypass grafting. There were 173 men and 119 women and their ages ranged from 39 to 84 years with a mean of $61.8{\pm}9.1$ years. We analyzed the preoperative risk factors, operative procedures and operative outcome. In addition, we analyzed the recurrence of symptoms, long-term mortality and complications via out-patient follow-up for discharged patients. Result: Preoperative clinical diagnoses were unstable angina in 137(46.9%), stable angina in 34(11.6%), acute myocardial infarction in 40(13.7%), non-Q myocardial infarction in 25(8.6%), postinfarction angina in 22(7.5%), cardiogenic shock in 30(10.3%) and PTCA failure in 4(1.4%) patients. Preoperative angiographic diagnoses were three-vessel disease in 157(53.8%), two-vessel disease in 35 (12.0%), one-vessel disease in 11(3.8%) and left main disease in 89(30.5%) patients. We used saphenous veins in 630, internal thoracic arteries in 257, radial arteries in 50, and right gastoepiploic arteries in 2 distal anastomoses. The mean number of distal anastomoses per patient was $3.2{\pm}1.0$ There were 18 concomitant procedures ; valve replacement in 8(2.7%), left main coronary artery angioplasty in 6(2.1%), patch closure of postinfarction ventricular septal defect(PMI-VSD) in 2(0.7%), replacement of ascending aorta in 1(0.3%) and coronary endarterectomy in 1(0.3%) patient. The mean ACC time was $96.6{\pm}35.3 $ minutes and the mean CPB time was $179.2{\pm}94.6$ minutes. Total early mortality was 8.6%, but it was 3.1% in elective operations. The most common cause of early mortality was low cardiac output syndrome in 6(2.1%) patients. The stastistically significant risk factors for early mortality were hypertension, old age($\geq$ 70 years), poor LV function(EF＜40%), congestive heart failure, preoperative intraaortic balloon pump, emergency operation and chronic renal failure. The most common complication was arrhythmia in 52(17.8%) patients. The mean follow-up period was $39.0{\pm}27.0$ months. Most patients were free of symptoms during follow-up. Fourteen patients(5.8 %) had recurrent symptoms and 7 patients(2.9%) died during follow-up period. Follow-up coronary angiography was performed in 13 patients with recurrent symptoms and they were managed by surgical and medical treatment according to the coronary angiographic result. Conclusion: The operative and late results of CABG in our hospital, was acceptable. However, There should be more refinement in operative technique and postoperative management to improve the results.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.1
• /
• pp.153-168
• /
• 1998

Background: The existing data indicate that obstructive sleep apnea syndrome contributes to the development of cardiovascular dysfunction such as systemic hypertension and cardiac arrhythmias, and the cardiovascular dysfunction has a major effect on high long-term mortality rate in obstructive sleep apnea syndrome patients. To a large extent the various studies have helped to clarify the pathophysiology of obstructive sleep apnea, but many basic questions still remain unanswered. Methods: In this study, the influence of obstructive sleep apnea on systemic blood pressure, cardiac rhythm and urinary catecholamines concentration was evaluated. Over-night polysomnography, 24-hour ambulatory blood pressure and ECG monitoring, and measurement of urinary catecholamines, norepinephrine (UNE) and epinephrine (UEP), during waking and sleep were undertaken in obstructive sleep apnea syndrome patients group (OSAS, n=29) and control group (Control, n=25). Results: 1) In OSAS and Control, UNE and UEP concentrations during sleep were significantly lower than during waking (P<0.01). In UNE concentrations during sleep, OSAS showed higher levels compare to Control (P<0.05). 2) In OSAS, there was a increasing tendency of the number of non-dipper of nocturnal blood pressure compare to Control (P=0.089). 3) In both group (n=54), mean systolic blood pressure during waking and sleep showed significant correlation with polysomnographic data including apnea index (AI), apnea-hypopnea index (AHI), arterial oxygen saturation nadir ($SaO_2$ nadir) and degree of oxygen desaturation (DOD). And UNE concentrations during sleep were correlated with AI, AHI, $SaO_2$ nadir, DOD and mean diastolic blood pressure during sleep. 4) In OSAS with AI>20 (n==14), there was a significant difference of heart rates before, during and after apneic events (P<0.01), and these changes of heart rates were correlated with the duration of apnea (P<0.01). The difference of heart rates between apneic and postapneic period (${\Delta}HR$) was significantly correlated with the difference of arterial oxygen saturation between before and after apneic event (${\Delta}SaO_2$) (r=0.223, P<0.001). 5) There was no significant difference in the incidence of cardiac arrhythmias between OSAS and Control In Control, the incidence of ventricular ectopy during sleep was significantly lower than during waking. But in OSAS, there was no difference between during waking and sleep. Conclusion : These results suggested that recurrent hypoxia and arousals from sleep in patients with obstructive sleep apnea syndrome may increase sympathetic nervous system activity, and recurrent hypoxia and increased sympathetic nervous system activity could contribute to the development of cardiovascular dysfunction including the changes of systemic blood pressure and cardiac function.