You-Sun Hong

Clinical Experiences of Cardiac Myxoma

Although cardiac myxoma is rare, it is the most common primary cardiac tumor. Seventy-four cases of cardiac myxoma that were surgically treated in our center between August 1980 and February 2005 were retrospectively reviewed. The mean patient age was 50.4 ± 15.0 (range 7-80) years, and 53 patients (71.6%) were female. The most common preoperative symptom, occurring in 44 patients, was dyspnea. The interval from onset of symptoms to surgery was 9 months. Seventy cases were located in the left atrium, 3 in the right atrium and 1 in the right ventricle. The myxoma in the right ventricle could not be resected completely, due to severe infiltration. Cardiopulmonary bypass and aortic cross clamp times were 100.4 ± 37.1 and 64.8 ± 29.8 minutes, respectively. There were no hospital deaths, and 7 patients suffered from postoperative complications including atrial fibrillation in 2 cases. During the follow up period (mean 105.7 ± 73.6 months), there was no tumor recurrence and 6 late deaths that were not related to the underlying tumor. There was no evidence of tumor growth in the cases with incomplete resection during the 14-month follow-up. In conclusion, in this study there was no recurrence of tumors after complete resection and surgical resection is considered to be the curative method of treatment for cardiac myxoma.

Comparison of Off-pump Coronary Artery Bypass Grafting With Percutaneous Coronary Intervention Versus Drug-Eluting Stents for Three-Vessel Coronary Artery Disease

BACKGROUND Drug-eluting stents (DESs) have challenged coronary bypass grafting as the gold standard for 3-vessel coronary artery disease. This study compared the clinical results between percutaneous intervention with DESs vs off-pump coronary bypass surgery (OPCAB). METHODS The study included 388 matched patients with 3-vessel coronary artery diseases who were treated either with DESs or OPCAB. We compared 30-day, 12-month, and cumulative major adverse cardiac and cerebrovascular events (MACCE) during the follow-up. RESULTS The overall follow-up was 98.5%. Follow-up duration was 621.1 +/- 259.9 days (range, 13 to 1117 days). The rates of MAACE in the DES and OPCAB group were, respectively, 1.5% at 30 days (p = 0.315) and 9.8% and 3.6% at 12 months (p = 0.015). During follow-up, five deaths occurred in the DES group and one in OPCAB group (p = 0.1). Three-year survival rate was 95.1% +/- 2.9% in DES group and 99.5% +/- 0.5% in OPCAB group (p = 0.075). Survival free from MACCE at 3 years was 73.3% +/- 5.3% in DES group and 91.3% +/- 2.9% in OPCAB group (p < 0.001). The major event for the differences between the groups was target vessel revascularization (p < 0.001): 21 DES patients (10.8%) vs 6 OPCAB patients (3.1%). CONCLUSIONS OPCAB showed better clinical outcome in 12-month and cumulative MACCE rate in 3-vessel coronary artery diseases. The major factor for the difference was target vessel revascularization. Longer follow-up is needed to clarify the differences between the two groups.

Changes in jugular bulb oxygen saturation during off‐pump coronary artery bypass graft surgery

Background:  The effect of haemodynamic derangement during coronary artery anastomosis in off‐pump coronary artery bypass surgery on cerebral blood flow has not been elucidated. Jugular bulb oxygen saturation is a useful indicator of cerebral blood flow provided that the cerebral metabolic rate is constant. This study was designed to evaluate the changes in jugular bulb oxygen saturation during off‐pump coronary artery bypass surgery.

The Haemodynamic Effects of Propranolol and Atenolol Medication on Dobutamine Infusion in Patients with Coronary Artery Obstructive Disease

We compared the haemodynamic effects of β-blockers on dobutamine infusion in 60 patients undergoing coronary artery bypass graft surgery. All patients had been taking propranolol (n = 30) or atenolol (n = 30) pre-operatively for at least 1 month. After sternotomy, dobutamine was infused at 2 μg/kg per min, and the dose increased to 4 μg/kg per min and then 8 μg/kg per min, at 15-min intervals. In both groups, dobutamine infusion did not increase the cardiac index or the heart rate, but was associated with an increase in mean arterial pressure, systemic vascular resistance index and mean pulmonary arterial pressure in a dose-dependent manner. The haemodynamic responses to dobutamine infusion were similar in the two groups. We conclude that pre-operative medication with β-blockers reduced the inotropic and chronotropic effects of dobutamine infusion. There was no difference between the modification produced by propranolol, a non-selective β -blocker, and that produced by atenolol, a selective β1-blocker, however.

Effect of angiotensin-converting enzyme inhibitors on phenylephrine responsiveness in patients with valvular heart disease

We studied patients with valvular heart disease to investigate whether chronic pre-operative treatment with angiotensin-converting enzyme (ACE) inhibitors modulates the effect of phenylephrine (PE) on anaesthesia-induced hypotension. Sixty-five patients were enrolled in the study and hypotension developed after anaesthesia in 36 (18 in the control group and 18 in the ACE inhibitor group). These patients received PE infusions, which were increased in a stepwise fashion at 10-min intervals. Increased mean arterial pressure due to PE infusion was significant only in the control group. There was no significant difference in pressor response or change in haemodynamic variables with PE infusion between the two groups. Treatment with ACE inhibitors did not increase the incidence of hypotensive episodes or significantly modify pressor response after anaesthesia in patients with valvular heart disease.

Clinical Results of Minimally Invasive Open-Heart Surgery in Patients with Mitral Valve Disease: Comparison of Parasternal and Low-Sternal Approach

Clinical results of minimally invasive mitral valve surgery were retrospectively reviewed, and two different surgical approaches were compared in this study. Between 1997 and 2004, a total of 86 patients with mitral valve disease underwent minimally invasive surgery at theYonsei University Cardiovascular Center. Age of patients averaged 41.6 ± 14.0 years and 69 patients were female. Surgical approach included lowsternal incisions with mini-sternotomy, and right parasternal or thoracotomy approach. Either direct aortic or femoral arterial and bicaval cannulations were used in all patients. Patients were divided into two groups according to the method of surgical approach (parasternal (P) vs low-sternal (L)), and the results were compared. Postoperative NYHA functional class improved to 1.1 ± 0.4 in all patients (no significant statistical difference between two groups). Mean wound length (P: 9.21 ± 1.10 vs L: 11.24 ± 0.82 cm, p<0.05), and mechanical ventilation time (P: 10.42 ± 4.36 vs L: 12.90 ± 5.00 min, p=0.04) was significantly shorter in parasternal group, and mean operation time(P:294.74 ± 59.41 vs. L:259.31 ± 54.36 min, p=0.03) was significantly shorter in low-sternal group. Mean cardiopulmonary bypass time, and aortic cross clamp time was also shorter in low-sternal group without statistical difference. There were 2 minor wound complications in all patients (p=NS), and no hospital death. Comparing the two different surgical approach of minimally invasive mitral valve surgery, parasternal approach is thought to be more beneficial in reducing postoperative scar, and intubation time.

Topical lidocaine effectively reduced the increase of systolic blood pressure after side-clamping of the aorta in off-pump cardiac surgery

Background:  Side‐clamping of the ascending aorta during off‐pump coronary artery bypass surgery (OPCAB) may be associated with a significant increase in systemic blood pressure which may rarely result in aortic dissection. We evaluated whether topical application of lidocaine on the ascending aorta could reduce the rise in systemic blood pressure during side‐clamping of the aorta in OPCAB.