• Journal of Chest Surgery
• /
• v.40 no.11
• /
• pp.727-732
• /
• 2007

Background: The reciptents of aortic valve replacement or a Bentall operation usually display various degrees of mitral regurgitation. When deciding whether or not to correct the mitral regurgitation, one must consider its severity, underlying causes and operative risk. Recently, the operation method for correcting the concomitant mitral regurgitation has been done through aortic root to reduce the operation time and the cardiac trauma. We report our experiences that transaortic mitral valve commissuroplasty done with aortic valve replacement or a Bentall operation has been a simple, less invasive, effective method in the operative management of mitral valve regurgitation without significant organic changes. Material and Method: Between June 2002 and June 2005, twenty patients under-went mitral valve commissuroplasty via the aortic root with aortic valve replacement (n=14) or a Bentall operation (n=7). The mitral valve regurgitation of the patients didn't exceed a moderate (grade 2) degree and there was no significant organic disease. The preoperative diagnosis of MR was established by TTE and intraoperative TEE, and the patients were followed postoperatively by TTE. The operative technique was a simple anterolateral commissuroplasty of the mitral valve with a single mattress suture via the transaortic annular approach after excision of the aortic valve leaflets. Result: The mean patient age was 56.2 years and 65% (n=13) were male. The preoperative MR was mild (grade 1) in 9 (45%), mild to moderate in 8 (40%), and moderate (grade 2) in 3 (15%) patients. There were no operative mortalities. The MR improved in all patients (p=0.002) and the left ventricular ejection fraction (LV EF) improved in 14 (70%) patients (p=0.005). The mean cross-clamp time for the patients who under- went aortic valve replacement with transaortic mitral repair was $62.1{\pm}13.9 min$ and this was $137.5{\pm}7.2 min$ for the patients who underwent a Bentall operation with transaortic mitral repair. Conclusion: For selected patients without significant mitral organic disease, transaortic mitral valve commissuroplasty combined with aortic valve replacement or a Bentall operation may be a feasible, effective method without adding significant aortic cross clamping time and more cardiotomy.

• Journal of Chest Surgery
• /
• v.42 no.4
• /
• pp.441-446
• /
• 2009

Background: Side clamping of ascending aorta during proximal graft anastomosis in coronary bypassing surgery in-creases the risk of direct aortic injury as well as embolization of intimal atheroma. Heartstring proximal sealing system (Guidant Corporation, Santa Clara, Calif), developed to avoid aortic side clamping, may minimize risks of such complications. The aim of the current study is to compare the surgical outcomes of the two proximal anastomosis techniquesi.e., Heartstring system versus aortic side clamping in off pump coronary bypassing' surgery (OPCAB). Material and Method: From January 2003 to August 2008, 499 patients underwent OPCAB. Of them, proximal graft anastomosis was performed using Heartstring system in 182 patients (Group I) and conventional manual anastomosis in 317 patients (Group II). The two groups were compared for postoperative major complications and mortality. Result: Two groups showed similar characteristics in terms of preoperative demographic data, left ventricular ejection fraction, renal function and history of diabetes, hypertension and smoking. Although there was no inter-group difference in the history of cerebral ischemia (p=0.48), preoperative brain magnetic resonance angiography revealed greater incidence of severe carotid artery stenosis (>75% of lumen) in the Group I than in the. Group II (44.5% in the Group I and 30.0% in the Group II, p=0.003). There were no inter-group differences in postoperative mortality (p=0.40) and complications (p=0.47) including neurologic events (3 in the Group land 2 in the Group II, p=0.258). Whereas neurologic events all comprised transient ischemic attacks in the Group I, they comprised multiple embolic strokes in the Group II. One patient in the Group II experienced aortic dissection during proximal anastomosis which resulted in ascending aortic replacement. Conclusion: Although proximal anastomosis using Heartstring system did not show statistically significant benefit over aortic side clamping, the. absence of embolic stroke maybe a definite benefit which may be better defined through further studies over a larger cohort.

• Journal of Chest Surgery
• /
• v.39 no.6 s.263
• /
• pp.449-455
• /
• 2006

Background: Female sex was known to be a risk factor for mortality after coronary bypass grafting (CABG), and women showed higher in-hospital mortality than men. Material and Method: Between 1992 and 1996, 147 consecutive patients (98 men and 49 women) undergoing CABG were included in the study. Most patients had undergone CABG with left internal thoracic artery and saphenous vein under cardiopulmonary bypass. We examined the influence of gender on survival after CABG and looked for risk factors for survival. Result: There was no in-hospital mortality in women, but 3 death (3.0%) in men. During the mean follow-up period of $138.5{\pm}23.0$ months, mortality was lower in women than in men (20.4% vs 44.9%, p=0.004), and the most common cause of death in women was chronic renal failure (40%). Survival in women at 1, 5, 10, and f4 years was 100%, $98.0{\pm}2.0%,\;81.2{\pm}5.6%,\;and\;78.4{\pm}6.1%$, respectively, which was better than in men (p=0.004). Although preoperative left ventricular ejection fraction was higher in women than in men, this did not affect early and long-term survival difference between two sexes (p=0.15). Risk factor for long-term survival in women was diabetes (p=0.033) and in men number of diseased coronary artery (p=0.006). Conclusion: Long-term survival after CABG was better in women than men. Risk factor for long-term survival in women was morbid disease rather than cardiac disease.

• Journal of Chest Surgery
• /
• v.43 no.5
• /
• pp.475-481
• /
• 2010

Background: We evaluated mid-term results of mitral annuloplasty using a flexible band and a completely rigid ring for mitral valve repair in patients with degenerative mitral regurgitation (MR). Material and Method: From January 2004 to September 2008, 71 patients (M:F=36:35, $55{\pm}13$ years) underwent mitral valve repair with mitral annuloplasty for degenerative MR. Ring annuloplasty was done using a Cosgrove-Edwards flexible band (Group I, n=43) or a Carpentier-Edwards classic ring (Group II, n=28). There were no differences in preoperative characteristics of the participants. Average duration of follow-up was 36 months (range: 2~69 mos). Result: There was no in-hospital mortality. Postoperative morbidity, which included atrial fibrillation (n=7) and low cardiac output syndrome (n=5) in groups I and II were similar. There was one late death in group II. The proportion exhibiting freedom from recurrent mitral regurgitation ($\geq$moderate) at 4 years in Groups I and II were, respectively, 94.5 and 91.8%, (p=0.695). Left ventricular ejection fraction decreased in the early postoperative period ($7{\pm}2$ days) and recovered by last follow-up ($25{\pm}16$ mos; p=0.002). The pattern was similar in groups I and II (p=0.905). Re-operation was performed in 3 patients (1 in Group I and 2 in Group II, p=0.316). Four-year event-free survival (free of adverse valve-related events) was 95.2% for Group I and 92.6% for Group II; this difference was not significant, p=0.646). Conclusion: The type of technique used in mitral annuloplasty to repair the mitral valve repair after degenerative MR did not affect mid-term clinical and functional results.

• Journal of Chest Surgery
• /
• v.41 no.4
• /
• pp.439-446
• /
• 2008

Background: The aim of this study was to investigate the relationship of the left ventricular (LV) systolic function, the LV dimension and the LV mass with the QT dispersion in patients with stable angina, and we also wanted to compare this relationship between patients with and without significant coronary stenosis on coronary angiography. Material and Method: 174 patients complained of typical angina and they had no associated ST segment or cardiac enzyme abnormalities. The patients were divided into 2 groups based on the results of coronary angiography: the patients with angiographic coronary stenosis ${\geq}50%$ made up group I (n=101), and the patients with angiographic coronary stenosis <50% made up group II (n=73). An echocardiogram for assessing the LV ejection fraction (EF), the LV dimension and the LV mass and a 12.lead electrocardiogram for assessing the QT dispersion were performed before the coronary angiography. Result: The QT dispersion was significantly greater in group I than that in group II (39.8 ms vs. 33.3 ms; p<0.05). For all the patients, all the parameters of LV dimension and LV mass had statistically positive correlation to the QT dispersion, but the LV mass was the only independently significant parameter that was correlated with the increased QT dispersion (p<0.05). For group I, none of the echocardiographic parameters had significant correlation with the QT dispersion. However, the LV dimension and LV mass had significantly positive correlation with the QT dispersion, and the LV mass was also the only independently significant parameter that was correlated with increased QT dispersion in group II (p<0.05). Conclusion: Our study demonstrated a significantly positive correlation of the QT dispersion to the LV dimension and the LV mass in patients with stable angina. These findings are present only in patients without significant coronary stenosis.

• Journal of Chest Surgery
• /
• v.39 no.1 s.258
• /
• pp.28-34
• /
• 2006

Background: There has been an increase in the number of elderly patients considered for coronary artery bypass grafting (CABG). Recently, there were many satisfactory reports of coronary artery bypass grafting (CABG) in old age due to the development in operative technique and postoperative management. We evaluated operative and follow-up results of patients 70 years of age and older compared to 60 years old. Material and Method: We retrospectively studied the cases of 74 consecutive patients 70 years or older (group A) who underwent a elective CABG from January 2000 to December 2003 and compared that of relatively young age group (group B, 60-69 years old). We compared preoperative characteristics, operation technique, postoperative results that effect outcome, also we investigated late mortality and cardiac events at follow-up periods. Result: Preoperative demographic and clinical characteristics of two groups were not different, except preoperative renal dysfunction(serum creatinine: $\geq$1.4 mg/dl) (group A 17, 23$\%$ vs group B 14, 9$\%$) (p=0.024). There was no difference of the mean number of distal anastomosis and the left ventricular ejection fraction in group A decreased significantly from 53.7$\pm$13$\%$ preoperatively to 49.9$\pm$ 12$\%$ postoperatively (p=0.02), but not changed in group B. There was no difference at operative mortality rate and postoperative major morbidity rate, but wound problem of saphenous vein harvest site was significantly higher in group A than group B (6.8$\%$ vs 0.7$\%$, p=0.02). The mean follow up duration was 24.3$\pm$13 months and the cumulative survival were 95.4$\%$ at 2 year and 79.9$\%$ at 4 year in group A and 95.4$\%$ at 2 year and 90.1$\%$ at 4 year in group B (p=ns). Conclusion: We conclude that age is not a factor of determination when we decide about operation because coronary artery bypass grafting in elderly more than 70 years old can be performed with a low mortality rate and acceptable morbidity rate.

• Journal of Chest Surgery
• /
• v.37 no.8
• /
• pp.660-664
• /
• 2004

Background: Dilution of blood cardioplegia is not needed in IAWBC as it is in cold blood cardioplegia because it does not aggregate red blood cells on normal body temperature and does not compromise micro coronary circulation. This study was designed to evaluate the safety and efficacy of undiluted potassium solution in IAWBC. Material and Method: Thirty patients who underwent CABG with IAWBC were grouped into dilutedplegia (n=14) and microplegia (n=16). Potassium was delivered conventionally with 4 : 1 delivery kit in the dilutedplegia group. The undiluted potassium was directly connected on the blood of oxygenator in the microplegia group. Result: There were no differences in sex, age, left ventricular ejection fraction, number of grafts, aortic cross clamping time, and the value of perioperative myocardial enzyme between the two groups. There were no perioperative myocardial infarction and hospital mortality. The amount of crystalloid cardioplegia was 1346$\pm$597 mL in dilutedplegia (mean$\pm$standard deviation, and 28$\pm$9 mL in microplegia (p<0.0001). The hematocrit during cardiopulmonary bypass was 21$\pm$4% in dilutedplegia and 24$\pm$3% in microplegia (p>0.05). 11 patients in dilultedplegia received blood transfusion, but 4 patients in microplegia received blood transfusion (p<0.05). The amount of urine and hemofiltration during the operation were more in dilutedplegia (1250$\pm$810 mL, 1689$\pm$548 mL) than in microplegia (959$\pm$410 mL, 1461$\pm$784 mL; p<0.05). Conclusion: The undiluted potassium of IAWBC in CABG operation is a safe, effective technique for myocardial protection to prevent fluid overload, and blood transfusion. There is no need to use the delivery kit.

• 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.40 no.6 s.275
• /
• pp.407-413
• /
• 2007

Background: The brain natriuretic peptide (BNP) level has been reported in some studies to be associated with the occurrence of atrial fbrillation (AF). The aim of this study is to evaluate the potential usefulness of the BNP level as a predictor of the occurrence of postoperative (postop) AF and to assess the relationship of the BNP level with the onset of AF and the restoration of sinus rhythm. Material and Method: From January 1, 2005 to February 28, 2006, 82 patients without a history of atrial arrhythmia that had undergone cardiac surgery were enrolled in the study. Blood samples for plasma BNP were drawn daily for all these patients from the preoperative (preop) day to the 7th postop day. The patient records were reviewed and postop EKGs were checked daily for AF until the time of discharge. Result: Patients were divided into two groups based on development of postop AF. Postoperative AF developed in 26 patients (31.7%). There was no significant statistical difference in age, sex distribution, preop left ventricle ejection fraction, hypertension, left ventricular hypertrophy, or the use of beta blockers between the non-postop AF and postop AF group. More patients in the AF group had undergone valve surgery (39.3% versus 76.9%, p=0.002). The preop left atrium size was significantly larger in the AF patients ($43.8{\pm}10.3 mm$ versus $49.8{\pm}11.5 mm$, p=0.029). The preop plasma BNP levels were higher in the postop AF patients ($144.1{\pm}20.8 pg/mL$ versus $267.5{\pm}68 pg/mL$, p=0.034). In the postop AF group, the plasma BNP level was the highest on the 3rd postop day. Postop AF developed in most patients by the 3rd postop day; restored sinus rhythm developed by the 7th postop day. Conclusion: Elevated plasma BNP levels may lead to the occurrence of postop AF in patients undergoing cardiac surgery. Patients who have a high risk of postop AF should be considered for aggressive prophylactic antiarrhythmic therapy.

• Journal of Chest Surgery
• /
• v.42 no.6
• /
• pp.763-769
• /
• 2009

Background: In the majority of cases, sternal instability and wound infection concomitantly present after a cardiac operation following conventional median sternotomy, and these complications have a major influence on the postoperative course. The aim of this study is to compare the results of the different sternal wiring techniques of sternal infection. Material and Method: Between April 2004 and December 2008, 157 adult patients underwent cardiac in group A, whereas 71 patients who had undergone modified Robicsek sternal wiring were included in group B. The incidences of sternal wound complications in the two groups were assessed. Result: The mean age of the group B patients was older than that of the group A patients ($61{\pm}10$ years vs $57{\pm}13$ years). The incidence of preoperative left ventricular dysfunction (ejection fraction <30%), chronic obstructive pulmonary disease, renal failure requiring dialysis and diabetes mellitus were significantly higher in Group B, whereas the other perioperative risk factors for infection were not significantly different between the two groups. Two patients in group A experienced superficial wound infection, whereas 4 patients in group B displayed superficial wound infection, but the difference was not statistically significant (p=0.255). Yet poststernotomy deep sternal wound infection appeared in 6 patients of group A, whereas none of the patients in group B displayed this malady. Conclusion: The modified Robicsek sternal wiring technique showed greater sternal stability even for the patient with a high risk for infection, and the technique caused a lower incidence of deep sternal wound infection.