Ozaki technique versus ross operation for complex aortic valve diseases in children: A retrospective cohort study.

BACKGROUND: The Ozaki technique demonstrated promising results in adults, but few studies reported on pediatric patients with limited follow-up time. This study aimed to evaluate the mid-term results of Ozaki technique compared with Ross operation for complex aortic valve (AV) diseases in children. MATERIALS AND METHODS: One hundred and seventeen children underwent either Ozaki (n = 64) or Ross (n = 53) operation from January 2017 to December 2023. The primary endpoint was incidence of moderate or severe regurgitation/stenosis (AR/AS) post procedure. RESULTS: No significant difference was observed in age (6.5±3.4 vs. 7.9±4.3 years) and weight (25.9±15.5 vs. 31.0±25.9 kgs) at surgery. The Ozaki group had significantly more patients in heart failure (20.3% vs. 1.9%, P = 0.003) before surgery and more patients needed ECMO installation (6.3% vs. 0, P = 0.125) after surgery. The Ozaki group were in worse status with more patients occurred heart failure (20.3% vs. 1.9%, P = 0.003) before surgery and needed ECMO installation (6.3% vs. 0, P = 0.125) after surgery. During follow up (20.4±17.3 vs. 22.7±22.8 months, P = 0.526), five patients (7.8%) in Ozaki group but no patients in Ross group required reoperations. The incidence of moderate or severe AR (28.1% vs. 3.1%) and AS (31.3% vs. 5.7%) were significantly higher than Ross group. Multivariate analysis identified lower age [HR:1.282 (95%CI:1.075-1.529), P = 0.006] and ECMO installation [HR:0.126 (0.018-0.887), P = 0.037] to be risk factors for moderate or severe AR, and higher aortic transvalvular gradient before discharge was confirmed as the only risk factor for moderate or severe AS (≥36 mmHg) at follow up in Ozaki group. CONCLUSION: Ozaki technique may be used as a palliative procedure for complex AV diseases in children, but its' mid-term results were not durable as Ross surgery, especially younger patients.

Biventricular function after Ebstein anomaly repair from a single-center echocardiography study.

OBJECTIVE: We aimed to examine biventricular remodeling and function after Ebstein anomaly (EbA) surgical correction using echocardiographic techniques, particularly, the relations between the biventricular changes and the EbA types. METHODS: From April 2015 to August 2022, 110 patients with EbA were included in this retrospective study based on the Carpentier classification. Echocardiography assessments during the preoperative, early, and mid-term postoperative periods were performed. RESULTS: The 54 patients with types A and B EbA were included in group 1, whereas the 56 patients with types C and D were in group 2. Seventy-eight patients underwent surgical correction of EbA. The median age at operation was 8.8 years. During the mid-term follow-up, only 9.1% of the patients had moderate or severe tricuspid regurgitation. Right ventricular (RV) systolic function worsened in group 2 at discharge (fractional area change: 27.6 ± 11.2 vs. 35.4 ± 11.5 [baseline], P < 0.05; global longitudinal strain: -10.8 ± 4.4 vs. -17.9 ± 4.7 [baseline], P = 0.0001). RV function slowly recovered at a mean of 12 months of follow-up. Regarding left ventricular (LV) and RV systolic function, no statistical difference was found between before and after surgery in group 1. CONCLUSION: A high success rate of surgical correction of EbA, with an encouraging durability of the valve, was noted. Biventricular systolic function was maintained fairly in most patients with types A and B postoperatively. A late increase in RV systolic function after an initial reduction and unchanged LV systolic function were observed in the patients with types C and D postoperatively.

Success rate of current human-derived gastric cancer organoids establishment and influencing factors: A systematic review and meta-analysis.

BACKGROUND: Human-derived gastric cancer organoids (GCOs) are widely used in gastric cancer research; however, the culture success rate is generally low. AIM: To explore the potential influencing factors, and the literature on successful culture rates of GCOs was reviewed using meta-analysis. METHODS: PubMed, Web of Science, and EMBASE were searched for studies. Two trained researchers selected the studies and extracted data. STATA 17.0 software was used for meta-analysis of the incidence of each outcome event. The adjusted Methodological Index for Non-Randomized Studies scale was used to assess the quality of the included studies. Funnel plots and Egger's test were used to detect publication bias. Subgroup analyses were conducted for sex, tissue source, histological classification, and the pathological tumor-node-metastasis (pTNM) cancer staging system. RESULTS: Eight studies with a pooled success rate of 66.6% were included. GCOs derived from women and men had success rates of 67% and 46.7%, respectively. GCOs from surgery or biopsy/endoscopic submucosal dissection showed success rates of 70.9% and 53.7%, respectively. GCOs of poorly-differentiated, moderately-differentiated and signet-ring cell cancer showed success rates of 64.6%, 31%, and 32.7%, respectively. GCOs with pTNM stages I-II and III-IV showed success rates of 38.3% and 65.2%, respectively. Y-27632 and non-Y-27632 use showed success rates of 58.2% and 70%, respectively. GCOs generated with collagenase were more successful than those constructed with Liberase TH and TrypLE (72.1% vs 71%, respectively). EDTA digestion showed a 50% lower success rate than other methods (P = 0.04). CONCLUSION: GCO establishment rate is low and varies by sex, tissue source, histological type, and pTNM stage. Omitting Y-27632, and using Liberase TH, TrypLE, or collagenase yields greater success than EDTA.

Bibliometrics analysis based on the Web of Science: Current trends and perspective of gastric organoid during 2010-2023.

BACKGROUND: Three-dimensional organoid culture systems have been established as a robust tool for elucidating mechanisms and performing drug efficacy testing. The use of gastric organoid models holds significant promise for advancing personalized medicine research. However, a comprehensive bibliometric review of this bur-geoning field has not yet been published. AIM: To analyze and understand the development, impact, and direction of gastric organoid research using bibliometric methods using data from the Web of Science Core Collection (WoSCC) database. METHODS: This analysis encompassed literature pertaining to gastric organoids published between 2010 and 2023, as indexed in the WoSCC. CiteSpace and VOSviewer were used to depict network maps illustrating collaborations among authors, institutions and keywords related to gastric organoid. Citation, co-citation, and burst analysis methodologies were applied to assess the impact and progress of research. RESULTS: A total of 656 relevant studies were evaluated. The majority of research was published in gastroenterology-focused journals. Globally, Yana Zavros, Hans Clevers, James M Wells, Sina Bartfeld, and Chen Zheng were the 5 most productive authors, while Hans Clevers, Huch Meritxell, Johan H van Es, Marc Van de Wetering, and Sato Toshiro were the foremost influential scientists in this area. Institutions from the University Medical Center Utrecht, Netherlands Institute for Developmental Biology (Utrecht), and University of Cincinnati (Cincinnati, OH, United States) made the most significant contributions. Currently, gastric organoids are used mainly in studies investigating gastric cancer (GC), Helicobacter pylori-infective gastritis, with a focus on the mechanisms of GC, and drug screening tests. CONCLUSION: Key focus areas of research using gastric organoids include unraveling disease mechanisms and enhancing drug screening techniques. Major contributions from renowned academic institutions highlight this field's dynamic growth.

Multicenter Comparison of Percutaneous and Surgical Pulmonary Valve Replacement in Large RVOT.

BACKGROUND: A percutaneous approach for pulmonary valve replacement (PVR) is a feasible alternative to surgical PVR in selected patients with severe pulmonary regurgitation after repair of tetralogy of Fallot. However, large right ventricular outflow tract (diameter ≥ 25 mm) remains challenging. METHODS: This retrospective multicenter study enrolled consecutive patients with large right ventricular outflow tract who underwent percutaneous PVR (Venus P-valve, Venus MedTech Inc, Hangzhou, China) (n = 35) or surgical PVR (homograft valve; n = 30) between May 2014 and April 2017. Patients were followed up at 1, 3, 6, and 12 months, and yearly thereafter. Main study outcomes were pulmonary valve function and right ventricular function at discharge and midterm follow-up. RESULTS: PVR was successful in all patients. Percutaneous compared with surgical PVR group had: similarly distributed baseline characteristics; shorter hospitalization, intensive care unit stay, and endotracheal intubation duration; lower cost; lower pulmonary valve gradient before discharge; lower pulmonary valve regurgitant grade (mean difference, -0.63; 95% CI -1.11 to -0.20, P = .022), pulmonary valve gradient (mean difference, -5.7 mm Hg; 95% CI -9.4 to -2.2 mm Hg, P = .005), and right ventricular end-diastolic volume index (mean difference, -9.5 mL/m2; 95% CI -16.9 to -3.1 mL/m2, P = .022); and greater right ventricular ejection fraction (mean difference, 5.4%; 95% CI 2.4%-8.3%, P = .002) at median 36 months follow-up, without deaths in either group. CONCLUSIONS: Percutaneous PVR using Venus P-valve appeared to be a safe, efficacious and minimally invasive alternative to surgical PVR in selected patients with large right ventricular outflow tract yielding better right ventricular and pulmonary valve function at midterm follow-up.

[DSAT Model on Identifying the Weak Difference Information of Corn Leaf Spectra Stressed by Heavy Metal Lead Ion].

Weak information measurement between the spectra is one of the toughest current research issues in the hyperspectral remote sensing domainTraditional measuring methods are difficult to distinguish the weak information differences. The experiment on the lead(Pb) pollution was designed based on its different concentrations, meanwhile, the hyperspectral reflectance, chlorophyll and lead ion(Pb2+) contents of corn leaves stressed by different Pb2+ concentrations were measured. However, it is difficult to distinguish the differences on weak information between the spectra and the pollution levels of corn leaves stressed by different Pb2+ concentrations because the spectral correlation coefficients have reached 0.999 according to the measured results. Due to this fact, a novel spectral similarity measuring method that is the derivative spectral angle tangent (DSAT) model, was put forward based on the spectral derivative processing, tangent function enhancement, spectral angle measurement, piecewise spectral detection and so on. In order to verify the feasibility and effectiveness of DSAT in distinguishing the differences of the similar spectra that their correlation coefficients reach 0.99, the DSAT was used to measure the weak information differences between the spectra of corn leaves stressed by different Pb2+ concentrations by the ways on detecting the whole waveforms and the sub-interval waveforms of corn leaf spectra. The experimental results showed that the relative chlorophyll concentration and Pb2+ contents of corn leaves were significantly correlated with the waveform difference information. It also proves that the DSAT model has better practicability and superiority in distinguishing the difference between the high similarity spectra.

[A New HAC Unsupervised Classifier Based on Spectral Harmonic Analysis].

Hyperspectral images classification is one of the important methods to identify image information, which has great significance for feature identification, dynamic monitoring and thematic information extraction, etc. Unsupervised classification without prior knowledge is widely used in hyperspectral image classification. This article proposes a new hyperspectral images unsupervised classification algorithm based on harmonic analysis(HA), which is called the harmonic analysis classifer (HAC). First, the HAC algorithm counts the first harmonic component and draws the histogram, so it can determine the initial feature categories and the pixel of cluster centers according to the number and location of the peak. Then, the algorithm is to map the waveform information of pixels to be classified spectrum into the feature space made up of harmonic decomposition times, amplitude and phase, and the similar features can be gotten together in the feature space, these pixels will be classified according to the principle of minimum distance. Finally, the algorithm computes the Euclidean distance of these pixels between cluster center, and merges the initial classification by setting the distance threshold. so the HAC can achieve the purpose of hyperspectral images classification. The paper collects spectral curves of two feature categories, and obtains harmonic decomposition times, amplitude and phase after harmonic analysis, the distribution of HA components in the feature space verified the correctness of the HAC. While the HAC algorithm is applied to EO-1 satellite Hyperion hyperspectral image and obtains the results of classification. Comparing with the hyperspectral image classifying results of K-MEANS, ISODATA and HAC classifiers, the HAC, as a unsupervised classification method, is confirmed to have better application on hyperspectral image classification.

[An algorithm of spectral minimum shannon entropy on extracting endmember of hyperspectral image].

It's significant to study the algorithm of endmember extraction, which is the key for pixel unmixing,in the fields of feature identification, abundance inversion, quantitative remote sensing and so on. Based on the theory of shannon entropy and Gaussian distribution function, a new algorithm, named spectral minimum shannon entropy (SMSE) method for extracting end-members of hyperspectral images, is proposed in the present paper after analyzing the characteristics of spectra of the hyperspectral images. This algorithm was applied to extract the endmembers of an AVRIRS hyperspectral image, it was found that these extracted endmember spectra have higher precision by matching with the spectral library of United States Geological Survey (USGS). At the same time, it was also found that the SMSE algorithm has better efficiency and accuracy for extracting endmember spectra through comparing and analyzing comprehensively the results of endmember extraction of the experimental data by using the methods of SMSE, pixel purity index (PPI), sequential maximum angle convex cone (SMACC) and so on. In addition, the SMACC and SMSE are used to extract the endmembers in a Hyperion hyperspectral image, and it is concluded that the results of the SMSE is better than the SMACC's. Thus, the SMSE algorithm can be thought to have a certain degree of universal applicability.

Methylenetetrahydrofolate reductase C677T gene polymorphism and essential hypertension: A meta-analysis of 10,415 subjects.

The methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism has been suggested to be associated with the risk of essential hypertension (EH), however, results remain inconclusive. To investigate this association, the present meta-analysis of 27 studies including 5,418 cases and 4,997 controls was performed. The pooled odds ratio (OR) and its corresponding 95% confidence interval were calculated using the random-effects model. A significant association between the MTHFR C677T gene polymorphism and EH was found under the allelic (OR, 1.32; 95% CI, 1.20-1.45; P=0.000), dominant (OR, 1.39; 95% CI, 1.25-1.55; P=0.000), recessive (OR, 1.38; 95% CI, 1.18-1.62; P=0.000), homozygote (OR, 1.59; 95% CI, 1.32-1.92; P=0.000), and heterozygote (OR, 1.32; 95% CI, 1.20-1.45; P=0.000) genetic models. A strong association was also revealed in subgroups, including Asian, Caucasian and Chinese. The Japanese subgroup did not show any significant association under all models. Meta-regression analyses suggested that the study design was a potential source of heterogeneity, whereas the subgroup analysis additionally indicated that the population origin may also be an explanation. Another subgroup analysis revealed that hospital-based studies have a stronger association than population-based studies, however, the former suffered a greater heterogeneity. Funnel plot and Egger's test manifested no evidence of publication bias. In conclusion, the present study supports the evidence for the association between the MTHFR C677T gene polymorphism and EH in the whole population, as well as in subgroups, such as Asian, Caucasian and Chinese. The carriers of the 677T allele are susceptible to EH.

Postoperative diaphragmatic paralysis after cardiac surgery in children: incidence, diagnosis and surgical management.

BACKGROUND: Cardiac surgery for congenital heart disease covers a wide spectrum from simple to complex cardiac and extracardiac malformations. Innovations in pediatric cardiac surgery and perioperative care over the past decades have allowed surgical correction or at least palliation in almost all complex congenital heart defects in the first years of life. Diaphragmatic paralysis (DP) due to phrenic nerve injury after congenital cardiac surgery is an important respiratory complication resulting with respiratory insufficiency, lung infections, prolonged hospital stay time and even death. METHODS: Between April 2001 and December 2010, among patients undergoing cardiac surgery for congenital heart disease, postoperative DP was diagnosed in 47/10 200 (0.46%) patients. Diaphragmatic placation was performed in 37/47 patients. DP was suspected in children who failed to wean from mechanical ventilation or in those with persistent respiratory distress when there is no cardiac cause. Decreased respiratory sounds in auscultation, paradoxical breathing during spontaneous ventilation and elevated hemidiaphragm on chest X-ray led us to use fluoroscopy, ultrasound and/or electromyogram (EMG). When chest X-rays did not have a diagnostic value in patients with persistent respiratory distress, bilateral DP was suspected and immediate fluoroscopy of EMG was performed for diagnosis. In all patients, diaphragmatic placation was performed using a thoracic approach, through the sixth or seventh intercostals space with lateral thoracotomy. RESULTS: A total of 47 patients (21 females and 26 males) with a median age of 7.21 months (range 0.27-71 months) were diagnosed DP after cardiac surgery. The incidence of DP was 0.46% after cardiac surgery. The paralysed hemidiaphragm was left side in 26/47 (55.3%), right side in 17/47 (36.2%) and bilateral in 4/47 (8.5%) cases. The assisted ventilation time after cardiac surgery was (450±216) (116-856) hours. The median time from cardiac surgery to surgical placation was (24±14) (5-56) days. No patient died in this study. The follow-up period was (26.2±16.8) months. The position of the plicated diaphragm was normal on chest X-ray, in all plicated survivors within the 1st, 6th and 12th months after discharge. CONCLUSIONS: DP caused by phrenic nerve injury during surgical intervention for congenital heart disease is an important risk factor in terms of morbidity during the postoperative period. Diaphragmatic placation appears a good option, especially in newborns and small children, to wean patients from mechanical ventilation and to prevent long-term side effects of mechanical ventilation.

Modified anastomosis for repair of supracardiac total anomalous pulmonary venous connection in infants.

Recurrent pulmonary venous obstruction after repair of total anomalous pulmonary venous connection (TAPVC) is usually restricted to the anastomosis between the pulmonary venous confluence and the left atrium. We describe a modified technique for repair of supracardiac TAPVC in infants. An L-shaped incision of left atrium is utilized and the right-sided anastomosis is enlarged by using autologous pericardium to create a large and tension-free anastomosis.

[Surgical treatment of aortico-left ventricular tunnel].

OBJECTIVE: To review 9 aortico-left ventricular tunnel (ALVT) patients in our hospital, describe the clinical features, diagnosis, treatments and follow-up. METHODS: We identified 9 patients from July 2002 to August 2008. Clinical and surgical details were reviewed. 7 patients were in NYHA class I and 2 in class III, 8 of 9 patients were diagnosed by echocardiography before operation. RESULTS: All patients underwent surgery under standard cardiopulmonary bypass. 2 with direct suture, 5 by patch closure of the aortic end and 1 by patch closure of both aortic end and left ventricular end of the AVLT. 1 underwent aortic valve replacement after incision of the ALVT. One patient died 2 month after operation because of endocarditis and acute heart failure. At follow-up (3 month to 6 years), 3 patients were in NYHA class I, 3 in Class II, 1 in class III and missed 1. No aortic regurgitation or trace in 2, little in 1, little to moderate in 2. The aortic mechanical valve is normal in 1 and paravalvular leakage in 1 patient. CONCLUSION: Aortico-left ventricular tunnel is a rare cardiac malformation with a good post-operative outcome. Surgery is an effective treatment. Long-term follow-up for post-operation is essential.

[Mid-term results of surgical treatment for aortic regurgitation with large left ventricle].

OBJECTIVE: To evaluate the recent and mid-term results of aortic valve replacement for aortic valve insufficiency with large left ventricle. METHODS: From Dec 1999 to Jan 2006, 31 patients with aorta insufficiency with the left ventricle larger than 80 mm, 30 males and 1 female, aged (36 -/+ 11), underwent aortic valve replacement and were followed up after discharge by mail and/or telephone call for (46 +/- 23) months (3-85 months), and followed up by ultrasonography for (25 +/- 24) months (3-70 months). The ultrasound cardiographic data were analyzed. Groups were divided according to heart function and LVED to analyze risk factors after operation. RESULTS: One case died before discharge from the hospital and 3 cases died during the follow-up. The left ventricular end-diastolic diameter (LVEDD) after operation was (69 +/- 11) mm, significantly smaller than that before operation [(86 +/- 8) mm, P = 0.001]. The LVEDD continued to decrease during the follow-up and became (55 +/- 10) mm. The ejection fraction early during the follow-up was (58 +/- 15), significantly higher than that before operation [(48 +/- 13)%, P = 0.001]. The heart function and LVEDD before operation had little effects on the long term mortality and left ventricle function. Conclusion The patients with aortic valve insufficiency and large left ventricle still have indication for surgical treatment and most of such patients have good results in mid-term follow-up.

[Early and middle outcomes of total arterial revascularization using exclusively internal mammary artery and radial artery].

OBJECTIVE: To evaluate the early and mid-results of the use of the radial artery alongside the internal mammary artery for complete arterial revascularization in coronary bypass surgery. METHODS: From January 1999 to January 2005, 123 patients with coronary artery disease with lesions in more than one branch (target vessel), 114 males and 9 females, aged 51.9 +/- 9.4 (32 approximately 74) underwent coronary artery surgery after the complete arterial revascularization pattern. Before the operation the left ventricular ejection fraction (EF) value ranged 30% approximately 78%, and 24 patients (21.1%) had poor ejection fraction (with the EF < 50%). Sixty-four patients (52%) had previous myocardial infarction. Four patients with unstable angina received urgent operation. 36 patients (29.3%) had disease of the left main trunk. 74% of the patients underwent off-pump bypass technique. The mean number of distal anastomoses was 2.6 +/- 0.4 per patient. 20 patients were followed up for 62 +/- 12.8 months (36 approximately 80 months). RESULTS: The early mortality was 0.8%. Postoperative complications included arterial fibrillation in seven patients (5.7%). One patient underwent IABP insertion because of low cardiac output, 3 patients were re-admitted because of heart failure, angina and arrhythmias. Three patients died of cardiac events. One patient underwent redo-CABG due to recurrent myocardial infarction and one patient underwent percutaneous coronary intervention because of stenosis of the arterial graft. CONCLUSIONS: Complete arterial revascularization using radial and mammary arteries provides excellent early results, showing a low mid-term complication rate and surgical morbidity.

Transplantation of mesenchymal stem cells from human bone marrow improves damaged heart function in rats.

BACKGROUND: Bone marrow-derived mesenchymal stem cells (MSCs) are of great therapeutic potential after myocardial ischemic injury. However, little is known about the biological characteristics of MSCs in patients with coronary artery disease and their effects on infracted myocardium. The present study evaluated the biological characteristics of MSCs from patients with coronary artery disease and their effects after being transplanted into infarcted myocardium using a rat model. METHODS: Sternal bone marrow aspirates were taken at the time of coronary artery bypass graft surgery. Mononuclear cells isolated from bone marrow were cultured based on plastic adherence. The morphology and growth characteristics of MSCs were observed in primary and successive passages. A myocardial infarction model was created in 27 adult rats. Two weeks later, animals were randomized into two groups: culture medium (group I, n=13) or MSCs (2x10(6)) from early passages labeled with BrdU (group II, n=14) were injected into the infarcted myocardium. Echocardiography, histological examination, and reverse transcription-polymerase chain reaction (RT-PCR) were performed four weeks after cell transplantation. RESULTS: Flow cytometry analyses demonstrated that adherent spindle cells from bone marrow are mesenchymal stem cells (positive for CD29 and CD44, but negative for CD34 and CD45). Growth curves showed that MSCs have great proliferative capability especially at early passages. MSCs implantation in the infarcted border zone improved left ventricular function significantly in group II compared with group I. However, despite improved left ventricular function, we did not observe significant regeneration of cardiac myocytes. Immunohistochemistry revealed only the expression of desmin in the engrafted MSCs, a marker of premature myocyte. Moreover, the improved left ventricular function in this study seemed to be secondary to the beneficial reverse remodeling induced by the increase of collagen in infarcted zone, the decrease in the adjacent myocardium, and the increase of neovascularization (capillary density: 192+/-7.8/mm2 in group II vs. 165+/-5.9/mm2 in group I, P<0.05). Reverse transcription-polymerase chain reaction (RT-PCR) results showed the expression levels of collagen I, collagen III, SDF-1 (stromal cell-derived factor-1), and VEGF (vascular endothelia growth factor) in the infarcted border zone were significantly higher in the MSCs treated group. CONCLUSIONS: The MSCs from patients with coronary artery disease have a typical phenotype with highly proliferative potential and the engrafted MSCs may regulate extracellular collagens and cytokines to prevent the ventricular scar from pathologic thinning and attenuate the contractile dysfunction of the infarcted heart.

Clinical application of bidirectional Glenn shunt with off-pump technique.

A study was conducted to evaluate the outcomes of the bidirectional Glenn shunt technique performed off-pump. Between April 1999 and April 2001, 36 patients underwent bidirectional Glenn shunt, unilateral in 28 patients and bilateral in 8 patients, without using cardiopulmonary bypass. The patients consisted of 25 males and 11 females with a mean age of 5.7 +/- 5.4 years and a mean body surface area of 0.72 +/- 0.34 m2. Preoperative percutaneous oxygen saturation was 75% +/- 7%, and pulmonary arterial pressure was 14.3 +/- 3.6 mmHg. There was no operative mortality. Chylothorax occurred in 1 patient in the early postoperative period. All the other patients were discharged without complications. Mean arterial oxygen saturation at discharge was 92.7% +/- 4.0%. This shunt technique is easy to perform and is helpful in the early management of patients with a functionally univentricular heart. However, much remains to be learned about this unusual physiological system.

[Radionuclide pulmonary perfusion imaging in evaluating pulmonary hypertension in patients with rheumatic heart disease].

OBJECTIVE: To evaluate the degree of pulmonary hypertension in patients with rheumatic heart disease using radionuclide pulmonary perfusion imaging. METHODS: The pulmonary perfusion in 25 patients with rheumatic heart disease was examined using scintigram with macroaggregates of (99m)Tc-labeled human serum albumin (PPS) before and 7 days after operation. PPS was analyzed for (1) pulmonary perfusion steady time (PT), right upper and lower lung count ratio (RULR). The results were compared with those of catheterization examination during the operation. RESULTS: The pulmonary arterial systolic pressure (PAs) and total pulmonary resistance (TPR) were (60 +/- 21) mm Hg and (421 +/- 106) dyn if PT > or = 20 seconds and RULR > or = 2; The PAs and TPR were (28 +/- 5) mm Hg and (188 +/- 28) dyn if PT < 20 seconds and RULR < 2. The PPS changed in most of the patients during early operation. CONCLUSION: The degree of injury in pulmonary vascular in patients with rheumatic heart disease could be quantitatively analysed by PPS.