• International Journal of Vascular Biomedical Engineering
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• 제4권1호
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• pp.9-16
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• 2006

In this article we introduce computer models that have been developed in the past to determine the concentration of metabolic gases, the oxygen and carbon dioxide, along the pulmonary circulation. The terminal concentration of these gases in the arterial blood is related with the total change of the partial pressure of the same gases in the alveoli for the time beginning with inspiration and ending with expiration. It is affected not only by the ventilation-perfusion ratio and the gas diffusion capacity of the lung membrane but also by the pulmonary defect such as shunt, dead space, diffusion impairment and ventilation-perfusion mismatch. Some pathological pulmonary symptoms such as ARDS and CDPD can be understood through the mathematical models of these pulmonary dysfunctions. Quantitative study on the blood oxygenation process using various computer models is therefore of foremost importance in order to monitor not only the pulmonary health but also the cardiac output and cell metabolism. Reviewed in this paper include the basic and advanced methods that enable numerical study on the gas exchange and on the arterial oxygenation process, which might depend on the various heart and lung physiological conditions listed above.

• Neonatal Medicine
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• 제28권1호
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• pp.1-6
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• 2021

Persistent pulmonary hypertension of the newborn (PPHN) is a consequence of the failure of a decrease in the elevated pulmonary vascular resistance after birth. Pulmonary vasodilators, including inhaled nitric oxide (iNO), have been the mainstream of targeted therapy for PPHN, but no drugs have been proven to be effective in preterm infants with PPHN. The fetus remains hemodynamically stable despite lower arterial oxygen tension and pulmonary blood flow as compared to full-term newborns. This adaptation is due to the lower oxygen requirement and high oxygen-carrying capacity of fetal circulation. The immature lungs of preterm infants are more vulnerable to reactive oxygen species, and the response of pulmonary vascular dilatation to blood oxygen tension is blunted in preterm infants. Recently, iNO has been reported to be effective in a selected group of preterm infants, such as those with prolonged preterm rupture of membrane-oligohydramnios-pulmonary hypoplasia sequence. PPHN in preterm infants, along with maximum supportive treatment based on fetal physiology and meticulous assessment of cardiovascular function, is in dire need of new treatment guidelines, including optimal dosing strategies for pulmonary vasodilators.

• Journal of Chest Surgery
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• 제24권7호
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• pp.719-724
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• 1991

A case of pulmonary atresia with intact ventricular septum was presented in a 10-month-old cyanotic female patient, which was congenitally rare. Infant with pulmonary atresia and intact ventricular septum usually require urgent surgical intervention. Angiogram showed the pulmonary atresia at the level of the pulmonary valve, the hypoplasia of tricuspid valve and atrial septal defect without patent ductus arteriosus. We performed the pericardial patch graft on the right ventricular outflow tract and pulmonary artery after ventriculotomy using pacemaker wire as electrical saw and main pulmonary arteriotomy and then modified Waterston shunt from the ascending aorta to patch on the right ventricular outflow tract without extracorporeal circulation. Patient was postoperatively good condition.

• Clinical and Experimental Pediatrics
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• 제57권10호
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• pp.461-463
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• 2014

Decreased exercise capacity after Fontan surgery is relatively common and the failure of the Fontan state gradually increases with age. However, there is no further treatment for patients with Fontan circulation. Pulmonary vasodilation therapy is an effective method to solve this problem because pulmonary vascular resistance is a major factor of the Fontan problem. Inhaled iloprost is a chemically stable prostacyclin analogue and a potent pulmonary vasodilator. We experienced two cases of Fontan patients treated with inhaled iloprost for 12 weeks. The first patient was an 18-year-old female with pulmonary atresia with an intact ventricular septum, and the second patient was a 22-year-old male with a double outlet right ventricle. Fifteen years have passed since both patients received Fontan surgery. While the pulmonary pressure was not decreased significantly, improved exercise capacity and cardiac output were observed without any major side effects in both patients. The iloprost inhalation therapy was well tolerated and effective for the symptomatic treatment of Fontan patients.

• Archives of Pharmacal Research
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• 제20권5호
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• pp.389-395
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• 1997

We investigated the interaction between nitric oxide and the renin angiotensin system in regulating isolated pulmonary arterial tension and pulmonary arterial pressure (PAP) in renal hypertensive rats (RHR) made by complete ligation of left renal artery. Losartan induced a depressor response that was smaller in RHR than in normotensive rats (NR) (3.3 and 7.0 mmHg, respectively, at 3.0 mg/kg, p<0.05), and the response was significantly reduced by $N^{G}$-nitro-Larginine methyl ester (L-NAME). Angiotensin II elevated the PAP (7.6 and 10.8 mmHg at $0.1 {\mu}g/kg$; 20.3 and 23.6 mmHg at $1.0{\mu}g/kg$, respectively) and contracted the isolated pulmonary artery ($pD_2$: 8.79 and 8.71, respectively) from both NR and RHR with similar magnitude, and these effects were significantly enhanced by L-NAME in NR, but not in RHR. Acetylcholine lowered the PAP slightly less effectively in RHR than in NR (3.8 and 6.0 mmHg at 10 .mu.g/kg, respectively) and relaxed the pulmonary artery precontracted with norepinephrine in both rats with similar magnitude ($E_max$: 60.8 and 63.6%, respectively), and the effect being completely abolished after pretreatment.with L-NAME or removal of endothelial cells. These results suggest that nitric oxide interacts with renin angiotensin system to control the pulmonary vascular tension and pulmonary arterial circulation of RHR.R.

• Tuberculosis and Respiratory Diseases
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• 제39권4호
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• pp.299-303
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• 1992

• Korean Circulation Journal
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• 제48권12호
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• pp.1135-1144
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• 2018

Background and Objectives: Mitochondria play a key role in the pathophysiology of heart failure and mitochondrial permeability transition pore (MPTP) play a critical role in cell death and a critical target for cardioprotection. The aim of this study was to evaluate the protective effects of cyclosporine A (CsA), one of MPTP blockers, and morphological changes of mitochondria and MPTP related proteins in monocrotaline (MCT) induced pulmonary arterial hypertension (PAH). Methods: Eight weeks old Sprague-Dawley rats were randomized to control, MCT (60 mg/kg) and MCT plus CsA (10 mg/kg/day) treatment groups. Four weeks later, right ventricular hypertrophy (RVH) and morphological changes of right ventricle (RV) were done. Western blot and reverse transcription polymerase chain reaction (RT-PCR) for MPTP related protein were performed. Results: In electron microscopy, CsA treatment prevented MCT-induced mitochondrial disruption of RV. RVH was significantly increased in MCT group compared to that of the controls but RVH was more increased with CsA treatment. Thickened medial wall thickness of pulmonary arteriole in PAH was not changed after CsA treatment. In western blot, caspase-3 was significantly increased in MCT group, and was attenuated in CsA treatment. There were no significant differences in voltage-dependent anion channel, adenine nucleotide translocator 1 and cyclophilin D expression in western blot and RT-PCR between the 3 groups. Conclusions: CsA reduces MCT induced RV mitochondrial damage. Although, MPTP blocking does not reverse pulmonary pathology, it may reduce RV dysfunction in PAH. The results suggest that it could serve as an adjunctive therapy to PAH treatment.

• Journal of Chest Surgery
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• 제19권4호
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• pp.726-730
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• 1986

Intralobar pulmonary sequestration is a rare congenital malformation characterized by a cystic portion of the lung that derives its arterial blood supply through aberrant vessel directly of systemic circulation. Two forms of pulmonary sequestration occur; intralobar sequestration is usually contained within the visceral pleura of a pulmonary lobe and its venous drainage to the pulmonary venous system. We presented on case of intralobar pulmonary sequestration with A-V fistula. The patient was 8 years old male and chief complaints are mild fever and exertional dyspnea. Aortogram revealed an aberrant artery originated from thoracic aorta just above the diaphragm and its vessel directly communicated pulmonary vein in sequestrated segment. At time of operation, sequestrated lobe measuring 6x5x5cm, well demarcated at the lower lobe was noted. Aberrant, measuring 1.0cm in diameter and 1cm in length and directly connected pulmonary vein. After division and ligation of the aberrant artery, only excision of sequestrated lobe was performed and complication is not during postoperative course.

• Journal of Chest Surgery
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• 제22권5호
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• pp.766-774
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• 1989

Four neonates with critical pulmonary outflow obstruction underwent emergency palliative operation between February 1988 and May 1989 at the department of Thoracic and Cardiovascular Surgery, Kyungpook National University Hospital. There were three boys and one girl, the mean age was 12.25 days [ranging from 3 days to 26 days], and the mean body weight was 3,625 gm [ranging from 3,450 gm to 4,200 gm]. Two patients had severe pulmonic valvular stenosis with intact ventricular septum, a third had pulmonary atresia with intact ventricular septum, and another had pulmonary atresia with ventricular septal defect. All were cyanotic, showed arterial desaturation with metabolic acidosis, and had congestive heart failure. To relieve the pulmonary outflow tract obstruction, we performed transventricular pulmonary valvulotomy [Brock operation] with a mosquito clamp in all cases without extracorporeal circulation. Three patients survived the operation and showed satisfactory postoperative results. The patient who had pulmonary atresia with ventricular septal defect expired 5 days after surgery. We consider transventricular pulmonary valvulotomy [Brock operation] with a mosquito clamp as one of the preferable procedures for critical pulmonary outflow obstruction in the neonatal period.

• Journal of Chest Surgery
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• 제28권12호
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• pp.1174-1177
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• 1995

We experienced one case of TAPVC patient who was 39 years old man with mild dyspnea on exertion and easy fatigability. He was the oldest patient among TAPVC which was reported in Korea. Preoperative echocardiogram, cardiac catheterization and angiogram revealed supracardiac type TAPVC drained through left innominate vein. An anastomosis between common pulmonary venous trunk and left atrium, pericardial patch closure of ASD and ligation of left vertical vein were performed with extracorporeal circulation. The postoperative course was uneventful and discharged with excellent general condition and has been well during 8 months follow-up.