Long Term Results of ST-Segment Elevation Myocardial Infarction versus Non-ST-Segment Elevation Myocardial Infarction after Off-Pump Coronary Artery Bypass Grafting: Propensity Score Matching Analysis

There is no consensus as to which acute myocardial infarction subtype poses a greater risk after coronary artery bypass grafting (CABG). We compared the early and the long term results of off-pump coronary artery bypass grafting (OPCAB) between patients with STEMI (group I, n = 83), and NSTEMI (group II, n = 237). Group I had higher EuroSCORE, prevalence of emergency surgery, preoperative intra-aortic balloon pump use, preoperative emergency percutaneous transluminal coronary angioplasty, and preoperative thrombolytic use than group II. There were no significant differences in 30-day mortality and major adverse cardiac and cerebrovascular event (MACCE) between groups. Overall 8-yr survival was 93% and 87% in groups I and II, respectively. Freedom from MACCE after 8 yr was 92% and 93% in groups I and II, respectively. After propensity score matching analysis, there were no significant differences in preoperative parameters, postoperative in-hospital outcomes, and long-term clinical outcomes. Surgical results of OPCAB in patients with acute myocardial infarction show good results in terms of long-term survival and freedom from MACCE, with no significant differences in clinical outcomes between STEMI and NSTEMI groups.

Delayed Diagnosis of Cardiac Tamponade That Was Caused by Intramural Hematoma of the Ascending Aorta: A case report / 대한흉부외과학회지

Intramural hematoma of the aorta (IMH) is the precursor or a variant of a classic aortic dissection where hemorrhage occurs within the aorta wall in the absence of an initial intimal tear. IMH has a high rate of mortality and morbidity. The optimal therapy for IMH is uncertain, yet the involvement of the ascending aorta is usually considered as an indication for surgery due to the associated risk of rupture or cardiac tamponade. We report here on a case of a 71-year-old man who presented with syncope. Because of misdiagnosis, he underwent computed tomography (CT) after 5 hrs from arriving to the ER. Computed tomography of the aorta revealed intramural hematoma of the ascending aorta with cardiac tamponade. He also had vascular complications such as acute renal failure and visceral ischemia. We performed emergency graft replacement of the total arch and ascending aorta. He was discharged without complication on postoperative day 14.

Open Pulmonary Thromboembolectomy in Patients with Major Pulmonary Thromboembolism

PURPOSE: We retrospectively analyzed open pulmonary thromboembolectomy in patients with acute and chronic pulmonary thromboembolism. MATERIALS AND METHODS: Between August 1990 and May 2005, 12 consecutive patients with acute and chronic pulmonary thromboembolism underwent open pulmonary thromboembolectomy at Yonsei Cardiovascular Center. Their mean age was 47.5 years, and 7 of the patients were female. Among 12 patients, 5 had acute onset, and 7 had chronic disease, and 9 patients were associated with deep venous thrombosis. Extent of pulmonary embolism was massive in 3 patients with hemodynamic instability, and submassive in 8 patients. Preoperative echocardiogram revealed elevated right ventricular pressure in all patients, and 7 patients were in NYHA functional class III or IV. Pulmonary thromboembolectomy was performed in all patients under total circulatory arrest. RESULTS: There were 2 hospital deaths (16.7%). Among the patients who survived, mean right ventricular pressure was decreased significantly from 64.3mmHg to 34.0mmHg with improvement of NYHA functional class. CONCLUSION: Open pulmonary thromboembolectomy is thought to be an immediate and definitive treatment for massive pulmonary embolism with optimal results. Even though operative mortality is still high, early diagnosis and immediate surgical intervention in highly selective patients may improve the clinical outcome.

Clinical Outcome of Emergency Coronary Artery Bypass Grafting after Failed Percutaneous Transluminal Coronary Angioplasty / 대한흉부외과학회지

BACKGROUND: Failed percutaneous transluminal coronary angioplasty (PTCA) is occasionally required for emergency coronary artery bypass grafting (CABG). The aim of this study was to assess the outcome of patients receiving emergency CABG after failed PTCA. MATERIAL AND METHOD: Between May 1988 and May 2005, 5712 patients underwent PTCA, where 84 (1.4%) failed. 27 patients underwent emergency CABG after failed PTCA. The mean age was 63.7+/-8.9 (46~80) years, with 14 male patients (51.9%). RESULT: All patients underwent emergent surgical revascularization within 6 hours. 22 patients underwent conventional CABG and 5 underwent off-pump CABG. The causes of PTCA failure were coronary obstruction due to new thrombi formation during the procedure (n=4), coronary dissection (n=17), coronary artery rupture (n=3) and 3 due to other causes. The rate of in-hospital operative mortality after emergent operation was 18.5% (5/27). A univariate analysis revealed that patients who died more often had left anterior descending artery disease, a preprocedural shock status, postoperative use of multiple isotropics and postoperative use of intra-aortic balloon pump. The mean follow up duration was 53.6+/-63.4 months. CONCLUSION: Although PTCA is known to be life saving, there is still a high risk for morbidity and mortality following emergency CABG after failed PTCA, despite the advancement in PTCA techniques. This result will help identify and more effectively treat patients selected for PTCA when emergency CABG is required.

Mid-Term Results of Reconstruction of the Right Ventricular Outflow Tract Using Cryopreserved Homografts

PURPOSE: Homograft benefits include excellent hemodynamics, resistance to infection, decreased thromboembolic events, ease of handling, and lack of need for anticoagulation. We examined the short and mid-term results of right ventricular outflow tract (RVOT) reconstruction using cryopreserved homografts. PATIENTS AND METHODS: From May 1998 to May 2005, 20 patients (male:female=10:10) underwent RVOT reconstruction using cryopreserved homografts. The median age was 23.8 years (range, 0.9 to 43.3 years) and the median body weight was 57kg (range, 7.3 to 80kg). Eighteen patients underwent re-operation after shunt or corrective operations. Homograft failure was defined as either re-operation for homograft replacement or patient death. Homograft dysfunction was defined as grade 3 or more than 3 of graft regurgitation and more than 40mmHg of transvalvular pressure gradient under echocardiographic examination. RESULTS: No operative mortality occurred and there were three major complications. Graft failure was observed in one male patient with tetralogy of Fallot. The 8-year freedom from graft failure was 87.5+/-11.7% and the 7-year freedom from graft dysfunction was 62.3+/-17.9%. Multivariable analysis revealed that the independent factor for graft dysfunction was age less than 10 years. In the analysis according to age group, the 7-year freedom from graft dysfunction in the group of patients older than 10 years was 100% and 25.0+/-21.7% in patients age 10 or younger (p= 0.03). CONCLUSION: Right ventricular outflow reconstruction using cryopreserved homografts provided excellent short and mid-term results in most patients in this study. However, in patients younger than 10 years old, homografts for RVOT reconstruction showed a high dysfunction rate at mid-term.

The Effect of Milrinone on the Right Ventriclular Function in Patients with Reduced Right Ventricular Function Undergoing Off-pump Coronary Artery Bypass Graft Surgery

This investigation evaluated the effect of continuous milrinone infusion on right ventriclular (RV) function during off-pump coronary artery bypass graft (OPCAB) surgery in patients with reduced RV function. Fifty patients scheduled for OPCAB, with thermodilution RV ejection fraction (RVEF) <35% after anesthesia induction, were randomly allocated to either milrinone (0.5 microgram/kg/min) or control (saline) group. Hemodynamic variables and RV volumetric data measured by thermodilution method were collected as follows: after anesthesia induction (T1); 10 min after heart displacement for obtuse marginal artery anastomosis (T2); after pericardial closure (T3). Cardiac index and heart rate increased and systemic vascular resistance significantly decreased in milrinone group at T2. Initially lower RVEF of milrinone group was eventually comparable to control group after milrinone infusion. RVEF did not significantly change at T2 and T3 in both groups. RV end-diastolic volume in milrinone group consistently decreased from the baseline at T2 and T3. Continuous infusion of milrinone without a bolus demonstrated potentially beneficial effect on cardiac output and RV afterload in patients with reduced RV function during OPCAB. However, aggressive augmentation of intravascular volume seems to be necessary to maximize the effect of the milrinone in these patients.

Ten Years Experiences of ATS Mechanical Valve / 대한흉부외과학회지

BACKGROUND: This study is to evaluate the safety of ATS valve by examining the clinical results of ten-years experience. MATERIAL AND METHOD: From July 1995 to March 2005, we reviewed 305 patients with ATS valve implantation. Mean age was 49.8+/-11.7 years and 140 (45.6%) males were included. Etiologies were rheumatic diseases in 207 cases (67.4%), degenerative changes in 57 cases (18.6%), valve dysfunction in 23 cases (7.5%) and infective endocarditis in 14 cases (4.6%). AVR was performed in 72 patients (23.5%), MVR in 156 patients (50.8%), DVR (AVR+MVR) in 63 patients (20.5%) and TVR in 16 patients (5.2%). RESULT: There were 9 operative mortalities (2.9%). Follow up period was 56.5+/-34.0 (0~115) months and 96.4% patients were followed up with 9 late deaths. Five and ten years survival rates were 94.9 +/-1.3%, 91.2+/-2.3% using Kaplan-Meier's methods. Valve related event free survival rates in 5 and 10 years were 90.8+/-2.0% and 86.9+/-3.2%. There were 16 anticoagulation-related hemorrhages, 6 thromboembolisms, 3 prosthetic valve endocarditis and 1 paravalvular leakage. NYHA class improved after operation (p <0.05). Postoperative echocardiography showed significant decrease in LA size, LVEDD and LVESD (p <0.01). Patients with 19 and 21 mm valve showed significantly higher transvalvular pressure gradient in aortic position (p <0.001, p <0.001). CONCLUSION: ATS valve showed good hemodynamic results with few valve related complications and thus can be used with acceptable risk.

Effects of Preoperative Continuous Use of Aspirin and Plavix in Off-pump Coronary Artery Bypass Surgery / 대한흉부외과학회지

BACKGROUND: The benefits of preoperative use of aspirin and plavix in coronary patients have been well documented. Due to their bleeding tendency, there have been many discussions about when to stop the antiplatelet agent before operation. We evaluated the effects of preoperative continuous use of aspirin and plavix in OPCAB patients. MATERIAL AND METHOD: 123 patients underwent OPCAB from March, 2004 to Feb., 2005. We divided them into two groups; those who had continuous administration of aspirin and plavix during the preoperative period (n= 45, 36.6%) and those who discontinued them at least one day before the operation (n=78, 63.4%). We then compared the platelet count, hemoglobin/hematocrit level, graft patency, postoperative bleeding and related complications, and operation time between the two groups. The patients were also divided into long-term users (> or =1 month) and short-term users (<1 month), with the aforementioned factors equally compared. RESULT: There was no statistical difference between the two groups regarding postoperative bleeding, related complications, graft patency, operation time and mortality. Continuous users showed significantly low platelet levels on immediate post operation (p=0.02), postoperative day (POD) #1 (p=0.002) and POD #2 (p=0.021), respectively. But there was no difference on POD #7. Long-term users showed statistically significant difference in pre- and postoperative platelet count, but none in postoperative bleeding and related complications. CONCLUSION: Continuous use of aspirin and plavix did not increase postoperative bleeding or related complications. Also graft patency and mortality had no statistical differences in continuous users. We think that there is no need to stop aspirin and plavix before OPCAB.

Left Ventricular Systolic Function Improvement after Surgical Revascularization in Postinfarction Angina / 대한흉부외과학회지

BACKGROUND: Acute myocardial infarction (MI) is a life-threatening disease and surgical revascularization plays a major role in selected cases. The purpose of this study is to evaluate the left ventricular contractility improvement by examining the wall motion score index (WMSI) and left ventricular ejection fraction (LVEF) in patients who underwent surgical revascularization under diagnosis of acute MI. MATERIAL AND METHOD: From January, 2001 to December, 2004, 149 patients who underwent coronary artery bypass surgery within 2 weeks of acute MI were included. We evaluated pre- and postoperative left ventricular contractility by measuring WMSI and LVEF and examined the associating factors. RESULT: WMSI decreased from 1.54+/-4.30 to 1.43+/-0.40 (p<0.001) and LVEF increased from 48.1+/-12.2% to 49.7+/-12.3% after surgery (p=0.009). Off-pump technique, non-Q wave, anterior MI, and surgery within 7 days after MI were favorable factors for LVEF improvement (p=0.046, p=0.006, p=0.003, p= 0.005, respectively). Conversely, aforementioned factors were irrelevant with WMSI improvement. For triple vessel disease, complete revascularization was favorable factor for WMSI improvement (p<0.001). CONCLUSION: Coronary artery bypass surgery can improve WMSI and LVEF in patients with acute MI. In case of anterior MI with non-Q wave, early surgical revascularization within 7 days may be most beneficial in LVEF improvement. Regarding WMSI, complete revascularization may be essential.

Spontaneous Recovery of Renal Function after Off-pump Coronary Artery Bypass Grafting in Chronic Renal Failure Patients / 대한흉부외과학회지

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) has shown better outcome in chronic renal failure (CRF) patients by avoiding the effects of cardiopulmonary bypass. We evaluated renal function after OPCAB in CRF patients. MATERIAL AND METHOD: 656 patients underwent OPCAB between January, 2001 and December, 2004. Data were collected in 26 CRF patients (Cr>1.7 mg/dL). Preoperative/postoperative creatinine (Cr) levels, creatinine clearance and postoperative data were evaluated. We divided the patients into group 1 (Cr or =3 mg/dL). RESULT: Three patients started dialysis after surgery. Preoperative mean creatinine level (4.19+/-3.4 mg/dL) was elevated to 4.36+/-2.7 mg/dL at the third postoperative day and decreased below preoperative level at the fifth postoperative day. In group 1 (mean Cr level=1.87+/-0.25 mg/dL), Cr level reached its peak level of 2.19+/-0.52 mg/dL at the fourth postoperative day (p=0.017), with subsequent decrease. Patients without pre- or postoperative dialysis (n=15) showed peak Cr elevation on postoperative day four (p=0.017) and subsequent decrease (p=0.01). Postoperative creatinine clearance showed reverse correlation with creatinine level. CONCLUSION: Creatinine level was elevated at third/fourth postoperative day, but decreased 5 days after surgery. Thus, if urgent dialysis is not indicated, postoperative renal replacement therapy in CRF patients may be better to be considered after four days observation.

Pseudofungi Associated with a Granulomatous Response in a Lymph Node: A Case Report

. We present herein a case of pseudofungi incidentally found in the mediastinal lymph nodes of a 31-year-old woman who had a left pneumonectomy for a pulmonary blastoma. The pseudofungi were located in the subcapsular sinuses of the lymph nodes with an associated granulomatous reaction. They revealed yellowish-brown hyphae-like structures with pseudosepta and irregular branching at various angles intermingled with round yeast-like forms. These structures stained positively with periodic acid-Schiff and Gomori methenamine silver, but also stained strongly positive for Prussian blue suggesting that they contain iron. The characteristic morphological features of pseudofungi are discussed with emphasis on the features that distinguish them from true fungal organisms.

Improvement of Fontan Circulatory Failure after Conversion to Total Cavopulmonary Connection / 대한흉부외과학회지

BACKGROUND: By improving the flow pattern in Fontan circuit, total cavopulmonary connection (TCPC) could result in a better outcome than atriopulmonary connection Fontan operation. For the patients with impaired hemodynamics after atriopulmonary Fontan connection, conversion to TCPC can be expected to bring hemodynamic and functional improvement. We studied the results of the revision of the previous Fontan connection to TCPC in patients with failed Fontan circulation. MATERIAL AND METHOD: From October 1979 to June 2002, eight patients who had failed Fontan circulation, underwent revision of previous Fontan operation to TCPC at Yonsei University Hospital. Intracardiac anomalies of the patients were tricuspid atresia (n=4) and other functional single ventricles (n=4). Mean age at TCPC conversion was 14.0+/-7.0 years (range, 4.6~26.2 years) and median interval between initial Fontan operation and TCPC was 7.5 years (range, 2.4~14.3 years). All patients had various degree of symptoms and signs of right heart failure. NYHA functional class was III or IV in six patients. Paroxysmal atrial fibrillation (n=1), cyanosis (n=2), intraatrial thrombi (n=2), and protein losing enteropathy (PLE) (n=3) were also combined. The previous Fontan operation was revised to extracardiac conduit placement (n=7) and intraatrial lateral tunnel (n=1). RESULT: There was no operative death. Major morbidities included deep sternal infection (n=1), prolonged pleural effusion over two weeks (n=1), and temporary junctional tachyarrhythmia (n=1). Postoperative central venous pressure was lower than the preoperative value (17.9+/-3.5 vs. 14.9+/-1.0, p=0.049). Follow-up was complete in all patients and extended to 50.1 months (mean, 30.3+/-12.8 months). There was no late death. All patients were in NYHA class I or II. Paroxysmal supraventricular tachycardia developed in a patient who underwent conversion to intraatrial lateral tunnel procedure. PLE was recurred in two patients among three patients who had had PLE before the convertsion. There was no newly developed PLE. CONCLUSION: Hemodynamic and functional improvement could be expected for the patients with Fontan circulatory failure after atriopulmonary connection by revision of their previous circulation to TCPC. The conversion could be performed with low risk of morbidity and mortality.

Clinical Significance of the Aortic Node in Non-small Cell Lung Cancer of the Left Upper Lobe / 대한흉부외과학회지

BACKGROUND: To clarify the clinical significance of the aortic nodes in resected non-small cell lung cancer of the left upper lobe. MATERIAL AND METHOD: One hundred fifty six patients with resected non-small cell lung cancer of the left upper lobe were studied. Patients who received preoperative induction therapy, non-curative operation or defined as operative mortality were excluded from this study. RESULT: In N2 left upper lobe tumors, aortic nodes comprised 52.7% of the metastatic mediastinal lymph nodes. In single station N2 disease, a frequently metastasized station was aortic node (64.3%). 5-year actuarial survival according to the N status was 65.0% in N0, 30.4% in N1, and 17.9% in N2. There was no statistically significant difference in survival between N1 and N2 diseases (p=0.06). The patients with metastasis to aortic node alone had a comparatively good prognosis (5-year survival: 35.6%) than other N2 diseases (5-year survival: 4.6%) (p=0.01) and had a similar survival outcome as N1 diseases (p=0.97). Considering the aortic node as N1 node, 5-year survival according to the N status was 65.0% in N0, 31.2% in N1, 4.6% in N2 and significant survival difference was observed between N1 and N2 disease (p=0.00). In multivariate analysis, the male sex (hazard ratio 6.892, p=0.011) and the involvement to the aortic node alone (hazards ratio 2.799, p=0.009) were the significant factors affecting postoperative survival. CONCLUSION: According to the our data, involvement to the aortic node alone in left upper lobe tumors should be grouped with N1 disease because this combined category reflects the surgical outcome more accurately.