Hepatic Veins ; physiopathology ; Humans ; Hypertension, Portal ; physiopathology ; Portal Pressure

PURPOSE: To verify the clinical correlation between retinopathy progression and the change of venous filling time (VFT), measured before and after panretinal photocoagulation (PRP), in proliferative diabetic retinopathy (PDR) patients. METHODS: We conducted this study on 32 patients (32 eyes) who received PRP for PDR. These patients were subdivided into two groups in accordance with the clinical course of PRP: the stabilized group in which retinal neovascularization was regressed and the progressed group in which retinal neovascularization was continued and a complication, such as vitreous hemorrhage or tractional retinal detachment, was developed within 12 months of laser treatment. Arteriovenous passage time (AVP) and VFT were measured by video fluorescein angiogram (FAG) using scanning laser ophthalmoscope (SLO) before and after PRP. VFT values were assigned by measuring by the time duration from start of venous lamina flow to the fullness of fluorescence on the vascular arch. RESULTS: In the stabilized group, AVP was decreased by 0.20+/-0.89sec and VFT was decreased by 0.30+/-1.69 sec through PRP. In the progressed group, AVP was increased in 0.12+/-1.22 sec and VFT was increased by 0.99+/-1.60 sec through PRP. In both groups, the VFT changes were significant (P=0.04) but the AVP changes were not (P=0.34). CONCLUSIONS: VFT was significantly decreased in the stabilized group and significantly increased in the progressed group after PRP. Accordingly, we suggest that VFT changes after PRP can be utilized as a prognostic indicator for evaluating clinical course of diabetic retinopathy after performing PRP and for monitoring the clinical effect of PRP.
Veins ; Time Factors ; Retinal Vessels/*physiopathology ; Regional Blood Flow ; *Light Coagulation ; Humans ; Diabetic Retinopathy/*physiopathology/*surgery

Superior vena cava (SVC) obstruction is associated with the gradual development of venous collaterals. We present a rare form of systemic-to-pulmonary subpleural collateral pathway that developed in the bridging subpleural pulmonary veins in a 54-year-old woman with complete SVC obstruction. This uncommon collateral pathway represents a rare form of acquired right-to-left shunt due to previous pleural adhesions with an increased risk of stroke due to right-to-left venous shunting, which requires lifelong anticoagulation.
*Collateral Circulation/physiology ; Female ; Humans ; Middle Aged ; Multidetector Computed Tomography ; Phlebography/methods ; Pulmonary Veins/physiopathology/*radiography ; Stroke/complications ; Superior Vena Cava Syndrome/physiopathology/*radiography ; Veins/physiopathology

OBJECTIVETo establish an animal model of congenital heart defect with decreased pulmonary blood flow for better understanding the pathophysiology of pulmonary vascular development and related regulatory mechanisms of congenital heart defect with decreased pulmonary blood flow.

METHODOne to two months old pigs were randomly divided into three groups: control group (group C, n = 6) with right chest small incisions induced transient pulmonary blood reduction; light-moderate stenosis groups (group T(1), n = 7): artificial atrial septum defect (ASD) plus controlled pulmonary artery banding to generate a systolic pressure gradient of 20 - 30 mm Hg (1 mm Hg = 0.133 kPa); severe stenosis groups (group T(2), n = 7): similar surgical procedures as group T(1), and controlled pulmonary artery banding to generate a systolic pressure gradient ≥ 30 - 50 mm Hg. 64-slice computed tomography scanning was performed at one month post operation. Arterial blood gas analysis, hemoglobin value, pulmonary vessel, ASD and banding ring diameters and trans-pulmonary artery banding pressure (Trans-PABP) were determined at two months post operation.

RESULTSOne pig died due to tracheal intubation accident in the C group, one pig died due to bowel obstruction in the T(1) group and two pigs died due to acute right heart failure and chronic heart failure respectively in T(2) group. 64-slice CT angiography results showed that aortic diameter of T(1) group was significantly lower than that of C group and banding diameter was significantly lower than aortic diameter in the T(1) and T(2) groups at one month post operation. Two months after operation, the size of ASD were (8.0 ± 0.5) mm and (8.9 ± 1.4) mm (P > 0.05) respectively in the T(1) and T(2) groups after operation. The Trans-PABP was significantly higher in the T(1) and T(2) groups than in C group (P < 0.01), and the Trans-PABP was significantly higher in the T(2) group than in T(1) group (P < 0.01). PaO2 and SaO2 in the T(1) and T(2) groups were significantly lower than those in C group.

CONCLUSIONArtificial atrial septum defect combined pulmonary artery banding procedures could be successfully used to establish model of congenital heart defect with decreased pulmonary blood flow and this model could help to understand the pathophysiology and monitor therapy efficacy for patients with congenital heart defect with decreased pulmonary blood flow.

Animals ; Disease Models, Animal ; Heart Defects, Congenital ; physiopathology ; Lung ; blood supply ; Pulmonary Artery ; physiopathology ; Pulmonary Circulation ; Pulmonary Veins ; physiopathology ; Swine

OBJECTIVESTo investigate the changes in intrahepatic portal systemic shunt flow (IHSF) and their relationship with microspheres induced acute portal hypertension.

METHODSFollowing acute intrahepatic presinusoidal obstruction by intraportal injection of 15 microm diameter microspheres in male Wistar rats, functional hepatic blood flow (FHBF) and IHSF were determined by hepatic sorbitol uptake methods. The percentage of large shunts of diameter > 15 microm were estimated by intraportal injection of 51Cr labeled 15 mum diameter microspheres.

RESULTSIn normal control rats, hepatic sorbitol uptake was 97.9%+/-0.5% and IHSF was negligible, with FHBF equaling total hepatic blood flow [(2.52 +/- 0.23) ml/min x 100 g body weight-1]. Microsphere injection decreased sorbitol uptake to 12.8% +/- 4.3% and further to 4.1% +/- 0.7% when followed by hepatic arterial ligation. In the latter two groups, IHSF (1.46 +/- 0.15 and 1.16 +/- 0.19 ml/min x 100 g body weight-1, respectively) was not significantly different from portal venous flow [(1.36 +/- 0.20) and (1.20 +/- 0.20) ml/min x 100 g body weight-1, respectively; t = 2.013 and t = 2.116]. Portal venous flow remained at 70% of basal values and portal venous pressure only increased by 50% from baseline. 51Cr labeled microsphere shunt fraction through large shunts (> 15 microm) was less than 1.0%.

CONCLUSIONIntrahepatic portasystemic shunts in the normal rat liver predominantly have diameters less than 15 microm and, when activated by intraportal injection of microspheres, they divert up to 70% of portal venous blood flow away from hepatic sinusoids and thereby they reduce acute increases in portal venous pressure.

Animals ; Hepatic Artery ; physiopathology ; Hepatic Veins ; physiopathology ; Hypertension, Portal ; chemically induced ; physiopathology ; Microspheres ; Portal Vein ; physiopathology ; Random Allocation ; Rats ; Rats, Wistar

OBJECTIVETo explore the characteristics of the portal vein hemodynamics and the correlation with the portal vein pressure.

METHODSThere were 41 cases of hepatic cirrhosis complicating portal hypertension. The liver function was graded Child-Pugh A+B in 31 cases and Child-Pugh C in 10 cases. The inner-diameter and blood stream speed of the portal vein (PV), the spleen vein (SV) and the superior mesentery vein (SMV) were measured by the color Doppler ultrasonography. The vascular acreage and blood flow volume were calculated. The portal vein pressure was directly measured during the operation. Thirty-two healthy people and 26 patients with chronic hepatitis B (CHB) served as controls in this study.

RESULTSThe inner-diameter of the three veins was obviously wider and the blood flow speed was slower in two portal hypertension groups than in CHB and normal groups (P<0.01). In Child C group, the speed was the slowest. The speed of SV and SMV in two hypertension groups did not show any significant difference (P>0.05). In Child A+B group, the blood flow volume of the three veins was larger than that in normal and CHB groups (P<0.01 or P<0.05). The volume of PV was less in Child C group than Child A+B group (P<0.01), but the volume of SV and SMV was not obviously different (P>0.05). In Child A+B group, the portal vein pressure (Ppv) had a close correlation with the portal vein width, blood flow quantitation (Qpv), and blood stream volume (Qsv) of the spleen vein.

CONCLUSIONSThe Qpv in Child A+B grade can be measured by the color Doppler ultrasonography technique, and the portal vein pressure can be monitored easily by the equation of Ppv=1.8951+0.0011Qpv.

Adult ; Blood Flow Velocity ; Female ; Hemodynamics ; Humans ; Hypertension, Portal ; physiopathology ; Male ; Mesenteric Veins ; physiopathology ; Middle Aged ; Portal Pressure ; physiology ; Portal Vein ; physiopathology ; Splenic Vein ; physiopathology ; Ultrasonography, Doppler, Color

Inter atrial block (IAB) is a prevailing cardiac conduction abnormality that is under-recognized in clinical practice. IAB has strong association with atrial arrhythmia, left atrial enlargement, and electromechanical discordance, increasing the risk of atrial fibrillation (AF) and myocardial ischemia. IAB was generally believed to be caused by impaired conduction along the Bachmann bundle (BB). However, there are three other conduction pathways, including the fibers posteriorly in the vicinity of the right pulmonary veins (VRPV), transseptal fibers in the fossa ovalis (FO), and muscular bundles on the inferior atrial surface near the coronary sinus (CS). We hypothesized that the importance of BB on IAB might have been overestimated. To test this hypothesis, various combinations of conduction pathway blocks were simulated based on a realistic human atrial model to investigate their effects on the index of clinical diagnosis standard of IAB using a simulated 12-lead electrocardiogram (ECG). Firstly, the results showed that the BB block alone could not generate typical P wave morphology of IAB, and that the combination of BB and VRPV pathway block played important roles in the occurrence of IAB. Secondly, although single FO and CS pathways play subordinate roles in inter atrial conduction, their combination with BB and VRPV block could also produce severe IAB. In summary, this simulation study has demonstrated that the combinations of different inter atrial conduction pathways, rather than BB alone, resulted in ECG morphology of IAB. Attention needs to be paid to this in future pathophysiological and clinical studies of IAB.
Adult ; Arrhythmias, Cardiac/physiopathology* ; Atrial Fibrillation/physiopathology* ; Computer Simulation ; Coronary Sinus/physiopathology* ; Electrocardiography ; Heart ; Heart Atria ; Humans ; Male ; Models, Anatomic ; Models, Cardiovascular ; Pulmonary Veins/physiopathology*

BACKGROUNDMajor atrial coronary arteries, including the sinus node artery (SNA), were commonly found in the areas involved in atrial fibrillation (AF) ablation and could cause difficulties in achieving linear block at the left atrial (LA) roof. The SNA is a major atrial coronary artery of the atrial coronary circulation. This study aimed to determine impact of the origin of SNA on recurrence of AF after pulmonary vein isolation (PVI) in patients with paroxysmal AF.

METHODSSeventy-eight patients underwent coronary angiography for suspected coronary heart disease, followed by catheter ablation for paroxysmal AF. According to the origin of SNA from angiographic findings, they were divided into right SNA group (SNA originating from the right coronary artery) and left SNA group (SNA originating from the left circumflex artery). Guided by an electroanatomic mapping system, circumferential pulmonary vein ablation (CPVA) was performed in both groups and PVI was the procedural endpoint. All patients were followed up at 1, 3, 6, 9 and 12 months post-ablation. Recurrence was defined as any episode of atrial tachyarrhythmias (ATAs), including AF, atrial flutter or atrial tachycardia, that lasted longer than 30 seconds after a blanking period of 3 months.

RESULTSThe SNA originated from the right coronary artery in 34 patients (43.6%) and the left circumflex artery in 44 patients (56.4%). Freedom from AF and antiarrhythmic drugs (AADs) at 1 year was 67.9% (53/78) for all patients. After 1 year follow-up, 79.4% (27/34) in right SNA group and 59.1% (26/44) in left SNA group (P = 0.042) were in sinus rhythm. On multivariate analysis, left atrium size (HR = 1.451, 95%CI: 1.240 - 1.697, P < 0.001) and a left SNA (HR = 6.22, 95%CI: 2.01 - 19.25, P = 0.002) were the independent predictors of AF recurrence.

CONCLUSIONSThe left SNA is more frequent in the patients with paroxysmal AF. After one year follow-up, the presence of a left SNA was identified as an independent predictor of AF recurrence after CPVA in paroxysmal AF.

Aged ; Atrial Fibrillation ; physiopathology ; surgery ; Catheter Ablation ; Coronary Vessels ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Pulmonary Veins ; surgery ; Recurrence

OBJECTIVETo observe the hemodynamic change and reperfusion injury cause by transient hepatic venous occlusion and transient hepatic inflow occlusion in rats.

METHODSThe rat liver was divided into 3 different areas: the ischemia reperfusion (IR) area: the inflow of the right superior lobe was clamped for half an hour; the non-isolated lobe congestive reperfusion (NIL-CR) area: the outflow of the right median lobe was clamped for half an hour; and the isolated lobe congestive reperfusion (IL-CR) area: the outflow of the left lobe was clamped for half an hour. The flux value and the oxygen saturation of microcirculation were monitored before at clamping for 30 minutes, and on 1 day, 3 days ,and 7 days after reperfusion. The hepatic damage and Suzuki's score were evaluated.

RESULTSAfter clamping for 30 minutes, the flux value in the IR area was significantly higher than in NIL-CR area (P<0.01) and IL-CR area (P<0.01), the oxygen saturation in the IR area was significantly higher than in NIL-CR area (P<0.01) and IL-CR area (P<0.05). Compared with IR area, both NIL-CR area and IL-CR area were found having more severe liver damage in terms of Suzuki's score in early postoperative period (at clamping for 30 minutes and on 1 day, P<0.01). However, there was no significant difference between NIL-CR area and IL-CR area in flux value, oxygen saturation, and Suzuki's score (P>0.05).

CONCLUSIONSHepatic venous occlusion can more effectively decrease the blood perfrusion and oxygen saturation; thus, compared to the IR, CR can result in more severe liver damage. The presence of normal liver tissue around the congestion area can not influence liver damage in transient hepatic venous occlusion.

Animals ; Disease Models, Animal ; Hemodynamics ; Hepatic Veins ; Liver ; physiopathology ; Male ; Microcirculation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; physiopathology

OBJECTIVEThe development status of pulmonary artery is one of the most important criteria for decision-making strategy and predicting postoperative outcome in congenital heart disease with decreased pulmonary blood flow. Currently, Nakata index and McGoon index have been used as morphologic index in evaluating the development status of pulmonary artery. Those indices have some shortcoming. It was recently found that pulmonary veins index is a more precise morphological indicator of pulmonary blood flow and development status of pulmonary vessels. This study aimed to explore an index of evaluating pulmonary blood stream and the development of pulmonary vessels, as a criterion for surgical decision-making strategy.

METHODSThe diameters of left and right pulmonary arteries and pulmonary veins were measured on DSA films in 74 patients with congenital heart disease with decreased pulmonary blood flow, The correlative analysis was done between Nakata index, McGoon index, pulmonary vein index (PVI) and postoperative outcome which were the length of stay in ICU, duration of mechanical ventilation and dose of inotropic drugs.

RESULTSExcellent correlations between the size of pulmonary veins and pulmonary arteries were found, the correlation between left pulmonary veins and distal portion of left pulmonary artery was 0.73, between left pulmonary veins and proximal portion of left pulmonary artery was 0.72, right pulmonary veins and distal portion of right pulmonary artery was 0.67, and right pulmonary veins and proximal portion of right pulmonary artery was 0.71. The length of stay in ICU, duration of mechanical ventilation and dose of inotropic drugs correlated well with PVI (r = -0.51, -0.478, and -0.693). Compared with Nakata index and McGoon index, PVI was a better criterion for evaluating the developmental status of the whole pulmonary vessels. In the right ventricular outlet reconstruction patients, the McGoon index for patients with low cardiac output syndrome (LCOS) was 1.36 +/- 0.51, and 1.97 +/- 0.58 for patients without LCOS (t = 2.347, P < 0.05), the Nakata index for patients with LCOS was 164 +/- 106 mm(2)/m(2) and 269 +/- 124 mm(2)/m(2) for patients without LCOS (t = 2.218, P < 0.05), the PVI for patients with LCOS was 152 +/- 77 mm(2)/m(2) and 273 +/- 125 mm(2)/m(2) for patients without LCOS (t = 2.936, P < 0.01), pulmonary vessel index of patients with LCOS was less than that of those without LCOS. When PVI was < or = 180 mm(2)/m(2), postoperative hemodynamics was unstable, the frequency of low cardiac output syndrome and mortality significantly increased.

CONCLUSIONSThe development of pulmonary arteries and pulmonary veins correlated with each other. PVI is a precise morphological indicator of pulmonary blood flow and development of pulmonary vessels. It is a helpful indicator to decide surgical strategy.

Adolescent ; Child ; Child, Preschool ; Female ; Heart Defects, Congenital ; physiopathology ; Hemodynamics ; Humans ; Infant ; Male ; Pulmonary Artery ; growth & development ; physiopathology ; Pulmonary Veins ; growth & development ; physiopathology