Asian Cardiovascular and Thoracic Annals

The aim of this prospective randomized study was to evaluate the effect of trimetazidine and diltiazem on persistent myocardial ischemia, mostly silent myocardial ischemia, after coronary artery bypass graft surgery. Sixty patients were divided into three groups of 20 each and followed up for 12 months. Patients in all 3 groups received acetylsalicylic acid 100 mg per day, those in group 1 also had trimetazidine 60 mg per day, and those in group 2 had diltiazem 90 mg per day. Each patient had coronary angiography during the first 3 weeks after surgery, 24-hour ambulatory monitoring every month, and cardiac scintigraphy at 3 weeks, 6 months, and 12 months. Ischemic episodes had resolved at 27 weeks in group 1, at 35 weeks in group 2 and at 51 weeks in group 3 (p < 0.05). Perfusion defects had resolved in the trimetazidine group at 6 months. At 12 months, perfusion defects had resolved in the diltiazem group but not in the group receiving only acetylsalicylic acid (p < 0.05). At these doses, trimetazidine and diltiazem were effective in decreasing silent myocardial ischemia following coronary artery bypass grafting. Trimetazidine appeared to be superior to diltiazem at 6 months on 24-hour ambulatory electrocardiogram monitoring and myocardial scintigraphy.

From September 1997 to January 1998, minimally invasive harvesting of the long saphenous vein was carried out on 30 randomly selected patients undergoing coronary artery bypass grafting. Two to 4 small skin incisions were made for subcutaneous dissection of the vein. The mean ratio of skin incision length to conduit length was 0.29 ± 0.01. The mean time for conduit preparation was 55 ± 2.6 minutes. Mean hospital stay was 9.2 ± 0.2 days. Morbidity in these patients was significantly lower than that of a control group of 100 patients who underwent the conventional open technique. The method was simple and effective in providing good quality venous conduits at low cost with improved patient satisfaction.

From December 1996 to December 1997, 58 patients underwent minimally invasive cardiac surgery in our institute. The operations comprised 10 for atrial septal defect, 26 for ventricular septal defect, 15 for mitral stenosis and insufficiency, 4 for aortic valve insufficiency, 2 for left atrial myxoma, and 1 for right ventricular myxoma. There were 21 men and 37 women with a mean age of 20 years (range, 5 to 46 years) and a mean weight of 35 kg (range, 15 to 68 kg). To establish cardiopulmonary bypass, femorofemoral and superior vena caval cannulation or femoral artery and two-stage cannulation was used. Normothermia with a beating heart or moderate hypothermia with aortic cross-clamping during cardiopulmonary bypass were employed. All patients resumed sinus rhythm spontaneously, except for one who was easily defibrillated. There were no deaths or neurologic complications and no problems with the cannulation sites. We concluded that these techniques of cardiopulmonary bypass were feasible and safe.

Eighteen rabbit hearts were arrested for 3 hours with cardioplegic solution at 4°C, followed by reperfusion with oxygenated perfusion solution at 37°C for 2 hours. Six control hearts received no drug during arrest or reperfusion (group 1). Six hearts received 3 mg·L⁻¹ aminophylline during the arrest period (group 2). Six hearts received 3 mg·L⁻¹ aminophylline during the reperfusion period (group 3). Effects of aminophylline were evaluated in terms of the pressure-volume relationship, coronary flow, myocardial oxygen extraction, and lactate release before cardioplegic arrest and after 1 and 2 hours of reperfusion. End-diastolic pressure at constant volume after 2 hours of reperfusion was 19 ± 2.63 mm Hg in group 1, 14 ± 1.7 mm Hg in group 2, and 19 ± 2.55 mm Hg in group 3 (p < 0.05 for group 2 versus groups 1 and 3). End-systolic pressure at constant volume after 2 hours of reperfusion was 81 ± 3.55 mm Hg in group 1, 90 ± 2.95 mm Hg in group 2, and 84 ± 3.47 mm Hg in group 3 (p < 0.05 for group 2 versus groups 1 and 3). Oxygen extraction was significantly higher and release of lactate was significantly lower in group 2 compared to groups 1 and 3. The results indicate that aminophylline administration during cardioplegic arrest improved systolic and diastolic function and had a beneficial effect on metabolic recovery.

Cultured rat aortic endothelial cells were morphologically and immunologically characterized before incubation under anoxic conditions for 120 minutes. Cell samples were reoxygenated for 10, 30, and 60 minutes as a model of anoxia-reperfusion injury. The effects of anoxia-reoxygenation were evaluated by measurements of membrane microviscosity, intracellular Ca²⁺ content, release of ⁵¹Cr, and uptake of trypan blue. Membrane microviscosity decreased from 2.03 ± 0.17 poise before anoxia to 1.72 ± 0.22 poise after 120 minutes of anoxia, with a further decrease to 1.54 ± 0.29 poise after 60 minutes of reoxygenation. Release of ⁵¹Cr correlated negatively with the decrease in membrane microviscosity and rose from 7.14% ± 0.4% to 12.16% ± 2.79% after anoxia and to 27.17% ± 2.59% after 60 minutes of reoxygenation. Intracellular Ca²⁺ content and uptake of trypan blue showed no noticeable change during anoxia but they increased significantly during reoxygenation. Addition of fructose-1,6-diphosphate to the anoxic incubation medium partly prevented the change in microviscosity and significantly reduced the release of ⁵¹Cr and the uptake of Ca²⁺ and trypan blue. Captopril exerted similar but less potent effects to those of fructose-1,6-diphosphate.

The electromechanical effects of protamine sulfate and the calcium channel blocker verapamil on rat cardiac and skeletal muscles were studied using isolated left ventricular papillary muscle and phrenic nerve-hemidiaphragm preparations. Protamine produced significant decreases in isometric force in the cardiac tissue and contracture developed at concentrations of 40 and 80 mg·L⁻¹. Isometric force also decreased significantly with verapamil at concentrations of 0.757 and 7.57 mg·L⁻¹. Both drugs caused significant decreases in the contractile force of hemidiaphragm muscle when the tissue was stimulated indirectly. Protamine and verapamil caused the resting membrane potential and the amplitude of the action potential to decrease in cardiac tissue and overshoot failed to develop with 80 mg·L⁻¹ of protamine or 7.57 mg·L⁻¹ of verapamil. These bioelectrical changes developed in a dose-dependent manner. It was concluded that protamine had a similar effect to that of calcium channel blockers and it may act through a reduction of cellular calcium. This effect on cardiac tissue may be mediated through the sarcolemmal ion pumps or channels, leading to changes in calcium homeostasis.

Of 60 consecutive patients with double-chambered right ventricle studied prospectively during a 42-month period, 7 had coexisting double-outlet right ventricle. There were 5 males and 2 females aged 4 to 20 years old. The clinical profile was similar to that of patients with tetralogy of Fallot. Echocardiography is recommended for the diagnosis of this condition.

We reviewed our 12-year experience of surgical treatment for aortic coarctation in 86 neonates. Twenty-three patients had simple coarctation, 38 had an associated large ventricular septal defect, and 25 had complex intracardiac defects. The surgical techniques included subclavian flap angioplasty in 54 (63%), combined resection with end-to-end anastomosis augmented by a subclavian flap in 22 (26%), resection with extended end-to-end anastomosis in 7 (8%), and patch aortoplasty in 3 (3%). Five patients required additional transverse aortic arch augmentation. Hospital mortality was 14% (12/86) and was not related to the type of repair but associated pathology increased the operative risk. Late mortality was 11% (8/74) within one year of repair. Recoarctation developed in 5 patients (7%) within one year. No recoarctation was observed in the group repaired by end-to-end anastomosis augmented by a subclavian flap (p = 0.04).

The fenestrated Fontan operation is commonly performed at several centers to decrease postoperative morbidity. Ultimately, the fenestrations are closed to avoid desaturation and embolism. Closure is safely accomplished in the operating room or in the catheterization laboratory with a device. We report our experience with the Amplatzer septal occluder that was successfully used to close residual shunts and fenestrations in two patients.

From April 1993 to March 1998, 90 patients with chest injuries were retrospectively assessed for the incidence, presentation, and outcome of thoracic trauma. The majority (55.6%) were less than 40 years of age and 83 (92%) were male. The mode and extent of injury, specific intrathoracic organ injuries, associated injuries, flail chest, ventilatory requirements, management, morbidity, and mortality were analyzed. Blunt injuries were seen in 56 (62.2%) and penetrating injuries in 34 (37.7%). Multiple rib fractures with hemopneumothorax was the most frequent presentation with orthopedic and head injuries being most commonly associated. Patients with tachypnea, cyanosis, lung contusion, partial pressure of aterial oxygen less than 60 mm Hg, and those with more than 6 rib fractures most often required ventilation but the majority (54.4%) were treated with a chest drain only. Emergency or delayed thoracotomy was required in 24.4%. The mortality rate was 6.7%, mainly due to respiratory insufficiency. Subcutaneous emphysema requiring releasing incisions accounted for most of the morbidity. Mean hospital stay was 9.5 days. Chest injuries were of major concern in multisystem trauma patients and early planned management is recommended in a mostly vulnerable section of our population in an age of violence and vehicular accidents.

We describe 4 cases of aortobifemoral bypass performed using a mini-laparotomy incision (6 to 8 cm) between January 1997 and February 1998. Revascularization of the lower extremities was carried out successfully without the need to enlarge the incision. The mean aortic cross-clamp time was 12.7 ± 3.4 minutes and the mean duration of the operation was 93.7 ± 30.9 minutes. In all cases, bowel sounds appeared at 2 to 8 hours postoperatively and oral nutrition was started after 24 hours. The mean hospital stay was 4.7 days. With the advantages of short operation time, optimal aortic exposure, easy and safe aortic cross-clamping, limited postoperative pain and scar tissue, early mobilization and resumption of intestinal functions, and short hospitalization, we believe that the mini-laparotomy technique is safe and effective for aortobifemoral bypass operations.

A 4-year-old boy with moderately severe factor VIII deficiency underwent successful intracardiac repair of tetralogy of Fallot under cardiopulmonary bypass with the aid of factor VIII concentrates and aprotinin.

Delayed pseudoaneurysm of the abdominal aorta is an exceedingly rare but potentially fatal complication following blunt abdominal trauma. A 25-year-old male presented 3 months after a road traffic accident with central abdominal pain. A 4-cm pseudoaneurysm of the infrarenal aorta was detected by computed tomography. Successful surgical repair was performed with an interposition graft and reimplantation of the inferior mesenteric artery.

Rupture of an ascending aortic aneurysm is the most common cause of death in patients with Marfan syndrome, while type-A aortic dissection is the second most common fatal lesion. The aortic root dimension and the rate at which it increases are the best indications for surgical treatment. We regard aortic enlargement to 5.5 cm as the upper limit of safety and we are inclined to advocate surgery at an earlier stage in high-risk families. We report our results of the surgical management of aortic aneurysm in the two siblings; a third sibling is currently being followed medically.

A 4-month-old male infant underwent elective repair of a large subaortic ventricular septal defect. Although it was an uneventful surgical procedure, he required inotropic support during weaning from cardiopulmonary bypass. He presented with sudden-onset low cardiac output syndrome in the immediate postoperative period and could not be revived. Autopsy revealed intussusception of the left atrial appendage projecting through the mitral valve orifice.

Adenoid cystic carcinomas are rare tracheal tumors that can mimic bronchial asthma. We describe the characteristics of 2 patients with adenoid cystic carcinoma who presented with symptoms suggestive of bronchial asthma of 2 years duration. Biopsy specimens revealed that the lesions were adenoid cystic carcinoma of the trachea. Both patients underwent collar incision and median sternotomy, the tumors were resected, and the tracheas were reconstructed primarily. Postoperative radiotherapy was given. Their postoperative clinical courses were uneventful and no local recurrences were seen at the 1-year follow-up.

A case of congenital ostial stenosis of the left main coronary artery with a large short patent ductus arteriosus is described. Revascularization was performed by autologous pericardial patch angioplasty and the ductus was closed simultaneously with a fabric patch.

A 26-year-old female presented with chest pain, numbness in the legs, and electrocardiographic signs of left ventricular aneurysm and recent myocardial infarction. Transesophageal echocardiography detected a mass in each atria. Angiography demonstrated normal coronary arteries, a left ventricular aneurysm, and an apical thrombus. At surgery, myxomas were excised from both atria and the aneurysm was plicated, followed by peripheral embolectomy. The patient made a good recovery.

Tricuspid valve endocarditis usually affects drug addicts without any preexisting heart disease. We report the successful surgical management of a case of tricuspid valve endocarditis with pulmonary artery embolism arising from postpartum septicemia.

Aortic dissections in the acute phase have a dramatic outcome, especially those in the ascending and arcus segments. The fate of these dissections in the chronic phase is not well established. We describe a case treated medically for over two years and then successfully repaired surgically.

Penetrating cardiac injury has the highest mortality and morbidity rates of any organ trauma. We describe a case of cardiac injury presenting with partial pericardial tamponade, which was caused by penetration of a ballpoint pen. The injury was diagnosed by chest radiography and successfully treated in a non-cardiac setup. Urgent investigation and surgical intervention are emphasized.

A 12-year-old boy who presented with recurrent syncope was diagnosed to have a hydatid cyst of the right ventricular outflow tract. He underwent emergency surgery for cyst rupture but died due to pulmonary embolism and right heart failure.