bluuebunny/crossref_metadata_2025_split huggingface dataset:
Usefulness of the Pulmonary Vein Flow Velocity-Time Profile as an Estimate of Left Atrial Storage Fraction
Authors: Arakawa Michio , Miwa Hiroshi , Noda Toshiyuki , Ito Yoshimi , Kagawa Kensaku , Nishigaki Kazuhiko , Kambara Kenjiro , Tomita Masaaki , Hirakawa Senri 
Published: July 2008

During ventricular systole, the left atrium (LA) stores a certain amount of ventricular stroke volume; this is defined as an LA storage volume. From cineangiocardiograms, an LA storage fraction is obtained as the ratio of the LA storage volume to left ventric ular stroke volume. From the pulmonary vein (PV) flow velocity-time profile, the LA storage fraction may be estimated as a ratio of the PV flow velocity-time integral during systole (Sa) to a sum of that during systole and diastole (Sa+Da), namely, Sa/(Sa+Da), provided that the PV cross-sectional area remains relatively unchanged during one cardiac cycle and that the PV flow velocity-time profile is similar in any of the PVs draining to the LA. To evaluate usefulness of Doppler echocardiographic method of estimating the LA storage fraction, the authors measured the LA storage fraction from the left upper PV flow velocity-time profile by transesophageal Doppler echocardiography and compared it with the LA storage fraction from conventional cineangiocardiographic volumes. (continued on next page) Subjects were 23 patients with a variety of cardiac diseases in normal sinus rhythm, ranging from eighteen to seventy-four years of age. The LA storage fraction was 0.58 ±0.12 (mean ±SD) from cineangiocardiography and 0.64 ±0.08 from Doppler echocar diography. Although the LA storage fraction from Doppler echocardiography was signif icantly larger than that from cineangiocardiography (P < 0.01), the correlation was good ( r=0.643). The authors conclude that the left upper PV flow velocity-time profile appears to provide a better correlation with that by cineangiography and may be used as a reliable quantitative estimate of the LA storage fraction.
Catheter-Directed Urokinase Thrombolysis: An Adjunct To PTA/Surgery for Management of Lower Extremity Thromboembolic Disease
Authors: Schilling Jolyon D. , Pond Gerald D. , Mulcahy Maureen M. , McIntyre Kenneth E. , Hunter Glenn C. , Bernhard Victor M. 
Published: July 2008

Catheter-directed thrombolysis was used either alone or as an adjunct to percutaneous transluminal angioplasty (PTA) or surgery for peripheral vascular occlusion on 112 occasions in 102 patients. Symptom duration ranged from < one to > twenty-eight days. Thrombolytic therapy using urokinase plasminogen activator thrombolysis (uPAT), including intrathrombic injection when possible, was successful (> 50% lysis) in 99 procedures (88%). Technical failure (<50% lysis) occurred in 13 procedures (12%). In 9 of the 13 failures, intrathrombic injection of urokinase was not possible, but the duration of occlusion was > twenty-eight days in all but 1. Two other failures were from embolic sources and 2 more occurred in patients with a hypercoagulable state. The uPAT was adjunctive to PTA/surgery in 56 cases (50%). PTA following uPAT was required and successfully performed in 24 of 27 cases (88.9%). Surgery followed lytic therapy in another 32 (including the 3 failed PTAs). In the remaining 56 cases (50%), no additional intervention was required. There were 20 complications (18%), minor in 16 of 20 (80%). Minor complications included small puncture site hematomas and distal embolization resolved by continued lytic therapy Four major complications occurred. One was retroperitoneal hemorrhage directly contributing to the only death in the series. The other 3 were hematuria (2) and femoral neuropathy (1). The authors conclude that catheter-directed lytic therapy alone or as an adjunct to PTA/surgery is a valuable approach to peripheral vascular thromboembolic disease. It is less likely to succeed in chronic occlusion. The incidence of complications is moderate but acceptable.
Effects of a Low-Dose Fish Oil Concentrate on Angina, Exercise Tolerance Time, Serum Triglycerides, and Platelet Function
Authors: Salachas Anastasios , Papadopoulos Constantinos , Sakadamis George , Styliadis John , Voudris Vasilis , Oakley David , Saynor Reginald 
Published: July 2008

Fish oils have shown beneficial effects on various parameters in patients with coronary artery disease (CAD). The purpose of this study was to investigate whether the same effects can be demonstrated with a low dose of fish oil concentrate (FOC). Thirty-nine patients were studied and divided into two groups. Twenty were given 10 g fish oil (group A) and 19 were given 10 g placebo Italian olive oil (group B). Weekly anginal attacks (AA), weekly glyceryl trinitrate consumption (GTN), exercise tolerance time (ETT), serum triglycerides (ST), platelet aggregation ratio (PAR), and β- thromboglobulin were measured at eight and twelve weeks after start of treatment. 1. The number of anginal attacks recorded by both groups decreased by 41% in group A reaching statistical significance (P < 0.05). No change was observed in group B. 2. GTN consumption decreased in group A (P < 0.05) with no significant change in group B (P: ns). 3. ETT increased significantly in group A eight and twelve weeks after start of treatment (20.6% P < 0.01, 22.6% P < 0.01). A smaller but insignificant increase was observed in group B (P: ns). 4. ST decreased significantly in group A by 22% eight weeks after start of treatment (P < 0.01) and to a lesser degree (11%) twelve weeks after start of treatment (P: ns). In group B, ST slightly increased (P: ns). (continued on next page) 5. No statistically significant change was observed in either group in regard to PAR and β-thromboglobulin (P: ns). These observations suggest that dietary supplementation with a low dose of FOC may have beneficial effects on the clinical status of patients with CAD. It also seems that this low dose has no impact on platelet function.
The Effect of a Cerebral Vasodilator, Vinpocetine, on Cerebral Vascular Resistance Evaluated by the Doppler Ultrasonic Technique in Patients with Cerebrovascular Diseases
Authors: Miyazaki Manabu 
Published: July 2008

Changes in cerebral vascular resistance were examined in patients with cerebral circulatory diseases by the Doppler ultrasonic technique after administration of a cerebral vasodilator, vinpocetine, for two months. Continuous index (CI) and pulsatility index (PI) of the blood flow pattern in the internal carotid artery were used as objective parameters for changes in cerebral vascular resistance. 1. The CI and PI changed significantly after administration of the drug; ie, the CI increased while the PI decreased. 2. An inverse correlation was noted between the rate of change of the CI (ΔCI) and that of the PI (ΔPI). 3. The results suggest that measurement of the CI and PI by the Doppler ultrasonic technique is useful in investigating the effect of drugs on the cerebral circulation.
Celiprolol vs Propranolol in Unstable Angina Pectoris: A Double-Blind, Randomized, Parallel-Group Study
Authors: Cleophas Ton J. , van't Leven Marjolein , Kauw Frans H. , Remmert Hendrik P. , Kuijper Aaf , Zwinderman Koos , Math D. 
Published: July 2008

Celiprolol, a novel beta blocker, may be more effective than propranolol in unstable angina pectoris because of both its beta-1-receptor selectivity and its vasodilator property In the present report 53 patients with angiographic coronary artery disease but uncom promised left ventricular function and with electrocardiographically documented recurrent angina pectoris in spite of bed rest, aspirin, and repeated sublingual adminis tration of nitroglycerin were studied. They were randomized for treatment with equipo tent doses of either the nonselective beta blocker propranolol (80 mg/day) or the selective beta blocker with beta-2-agonistic property, celiprolol (200 mg/day) during one week. Angina frequency was higher in the propranolol group (P < 0.01), whereas myocardial oxygen demand as estimated by the double product (DP = SBP x HR, systolic blood pressure x heart rate) was equally reduced by the two beta blockers. Forearm blood flow was essentially higher in the celiprolol group (P < 0.001). A stepwise logistic regres sion analysis showed that the beneficial effects of the beta blockers were largely dependent on their effect on peripheral flow, in addition to reduction of the double product. The authors conclude that (1) Both celiprolol and propranolol largely reduce angina pectoris frequency in unstable angina pectoris. (2) Celiprolol contributes to nearly complete relief in three times as many patients as propranolol; after adjustment for double product or for systolic blood pressure plus heart rate it performs even eight times better. (3) The similar effects of the two compounds on the double product and the essen tially different effects on peripheral flow support the conclusion that celiprolol exerts its beneficial effect to a large extent through its vasodilator property
Do Hydrophilic Guidewires Affect the Technical Success Rates of Percutaneous Angioplasty?
Authors: Hartnell George G. , Jones Ann M. , Murphy Paula 
Published: July 2008

To determine whether the use of hydrophilic guidewires has influenced the success of peripheral percutaneous transluminal angioplasty (PTA), the results of PTA performed before and after the introduction of such guidewires (end of 1989) were analyzed. Before hydrophilic guidewires became generally available, the technical success rates for iliac stenosis PTA were 96%, for femoral stenosis PTA 84%, and for femoral occlusion 78%. After the introduction of hydrophilic guidewires, technical success rates were 100% (NS), 97% (P=0.018), and 97% (P=0.011), respectively. A prospective study of 33 patients randomly selected for PTA of femoropopliteal occlusion using either conventional or hydrophilic guidewires was performed. In this group, the technical success rate was 14/15 in the hydrophilic group, and 18/18 in the conventional group (NS). Since the introduction of hydrophilic guidewires, the technical success rates of PTA have improved and are now approaching 100%.
Beneficial Effects of Antioxidants in Hemorrhagic Shock
Authors: Kapoor Rakesh , Prasad Kailash 
Published: July 2008

The present study was undertaken to investigate the role of endogenous hydrogen peroxide (H202) in cardiac depression and cytotoxicity during hemorrhagic shock and reinfusion. To achieve this objective, the changes in the cardiac function and contractility, plasma creatine kinase (CK) and CK-MB activity and lactate concentration, oxyradical producing activity of polymorphonuclear leukocytes (PMNL-CL), and cardiac malondi aldehyde (MDA) concentration in anesthetized dogs were determined before and during shock and reinfusion in the presence or absence of catalase (a metabolizer of H2O2). The dogs were divided into three groups randomly. Group I: sham, four hour duration; group II: two hours of shock followed by two hours of reinfusion; group III: same as group II but pretreated with catalase. Hemorrhagic shock was produced in the dogs by lowering the mean arterial pressure to 50 ±5 mm Hg by bleeding into standard blood bank bags containing 63 mL of citrate, phosphate, dextrose, and adenine (CPDA) anticoagulant for 450 mL of blood. The shock was maintained for two hours by bleeding or reinfusing the shed blood as needed.Cardiac function and contractility were depressed while plasma CK, CK-MB, and lactate increased during shock. Reinfusion after two hours of shock tended to return hemodynamic parameters and plasma lactate levels toward control values. Plasma CK and CK-MB and PMNL-CL increased further. Cardiac MDA content also increased after shock and reinfusion, suggesting oxidative damage. Pretreatment with catalase attenu ated the deleterious effects of shock and reinfusion on the cardiovascular function and contractility, and the rise in plasma CK, CK-MB, and lactate, PMNL-CL, and cardiac MDA. However, the protection with catalase was not complete. These results suggest that hydrogen peroxide (H202) may partly be involved in the deterioration of cardiovascular function and cellular injury during hemorrhagic shock and reinfusion.
Quality Assurance of High-Dose IV Heparin Treatment Exemplified by Patients Implanted with Coronary Palmaz-Schatz Stents
Authors: Haushofer Alexander , Halbmayer Walter Michael , Prachar Herbert , Fischer Michael 
Published: July 2008

The need to standardize treatment with high-dose IV standard heparin by using activated partial thromboplastin time (APTT) reagents tested for their heparin sensitivity and by establishing a standard treatment schedule led to the development of the "Lainz concept" of heparin management. The determination of heparin sensitivity of the 2 APTT reagents used (APTT Micronized Silica and APTT Actin FSL), their good agreement (r=.9977; P=.000), and their therapeutic APTT ratio of 1.5-2.5 fold of baseline APTT (therapeutic range, forty-five to seventy-five seconds) equivalent to 0.3-0.7 antifactor Xa units are presented. The "Lainz concept" was tested in 29 patients receiving high-dose heparin after coronary artery stenting. A mean dose of 1,273 U of standard heparin/hour (15.7 U/kg body weight/hour) was shown to produce APTTs in the therapeutic range. From the introduction of the "Lainz concept" 81% of the APTTs were kept within the therapeutic range by using a defined heparin-monitoring schedule based on a guideline protocol for controlling heparin treatment. Only 19% of the APTTs were below the therapeutic range. Factors underlying subtherapeutic APTTs are discussed. The reduction in the rate of subtherapeutic APTTs to less than 3% seen after the introduction of the "Lainz concept" constitutes an important contribution toward quality assurance in high-dose heparin treatment.
A Quantitative Analysis of the Structure of Right Ventricle-Pulmonary Artery Junction for Balloon Pulmonary Valvuloplasty in Children
Authors: Hwang Betau , Chen Li-Yun , Lu Jen-Her , Meng C. C. Laura 
Published: July 2008

Percutaneous balloon valvuloplasty (PBVP) was performed in 55 children, aged from four days to twelve years and nine months, with different severity of congenital pulmonary stenosis (PS). To evaluate its efficacy, a quantitative analysis of the structure of right ventricle-pulmonary artery junction was conducted. Significant reductions of peak systolic right ventricular pressure, ratio of peak right-to-left ventricular pressure, and pressure gradients between the right ventricle and pulmonary artery were obtained in 48 children who scored 3 or less (Group I) and 7 children who scored over 3 (Group II) (P<0.05). After two to forty-six months (M ± SD = 17.1 ±15.5 months) of follow-up study, the residual gradients between right ventricle and pulmonary artery over 36 mmHg were higher in children who scored over 3 than in those who scored 3 or less (71.4% vs 20.8%) (P<0.01). Repeated percutaneous balloon valvuloplasty was successfully performed in 4 children, 2 each in Group I and Group II. Surgical open pulmonary valvotomy was needed in 1 in Group II because of the dysplastic pulmonary valve and the need for repair of atrial septal defect and in 2 in Group I because of the failure to complete repeated PBVP in the catheterization laboratory or the need for repair of associated atrial septal defect.
Impaired Thermoregulation in Raynaud's Phenomenon
Authors: Greenstein D. , Gupta N.K. , Martin P. , Walker D.R. , Kester R.C. 
Published: July 2008

In an attempt to examine the role of the thermoregulatory apparatus in the etiology of Raynaud's phenomenon (RP), the authors exposed 15 women with RP and 12 controls to central body cooling and central body warming. Subjects were placed in an environ mental chamber at 25°C. Their right hand was placed in an annex of the chamber, which was insulated from the main chamber and maintained at a constant temperature of 25°C throughout the experiment. Blood flow was measured in the digits of the right hand by venous occlusion strain gauge plethysmography and skin thermometry. Body temperature was measured with an oral thermometer. The temperature of the chamber was then increased to 35°C and then reduced to 13°C for twenty-five minutes with measurements repeated. Following this period patients were rewarmed in an ambient temperature of 35°C for twenty minutes. Results: subjects with RP had significantly lower blood flow at all stages of the test; moreover, their digital rewarming response following central cooling was considerably prolonged when compared with controls. Body temperature was lower and dropped significantly more in the RP group following the cold challenge. The authors conclude that subjects with RP have an impaired thermoregulatory mechanism. This may partially explain cold sensitivity.
Endothelium-Derived Vasoactive Substances in Bartter's Syndrome
Authors: Calò Lorenzo , Cantaro Salvatore , Calabrò Alessio , Piarulli Francesco , Rizzolo Monica , Favaro Silvana , Antonello Augusto , Crepaldi Gaetano , Borsatti Arturo 
Published: July 2008

An imbalance between endothelium-derived vasoactive substances such as endothelin and endothelium-derived nitric oxide (NO) might be viewed as a possible determinant of vascular hyporeactivity. To check this possibility the authors evaluated the role of endothelin and NO in the reduced vascular reactivity of Bartter's syndrome. Plasma immunoreactive endothelin (22.07 ±7.06 vs 13.80 ±1.43 pmol/L, P < 0.011), urinary excretion of NO 2- (0.28 ±0.10 vs 0.15 ±0.02, μmol/μmol of urinary creatinine, P < 0.01) and NO3- (0.17 ±0.07 vs 0.09 ±0.02 μmol/μmol of urinary crea tinine, P < 0.011), and forearm resting blood flow (FRBF) (6.67 ±1.69 vs 4.30 ±0.38 mL/m'/100 mL, P < 0.005) were increased in patients with Bartter's syndrome in comparison with normal controls (C). No difference in postischemic maximal FBF was found (34.14 ±4.67 vs 31.35 ±2.86 mL/minute/100 mL), while patients showed a slower recovery after peak flow (PF) (77.57 ±61.35 vs 9.42 ±3.69 seconds, P < 0.013). Higher plasma endothelin supports the defect in vascular reactivity of Bartter's syndrome already shown for angiotensin II and norepinephrine and is in keeping with the altered intracellular calcium signaling previously demonstrated by the authors in this syndrome. The increased excretion of NO2- and NO3- in this syndrome, together with the higher FRBF and the slower recovery of the FBF after PF, argues in favor of an increased NO synthesis in Bartter's syndrome and of assigning it a role in the vascular hyporeactivity of Bartter's syndrome.
Myocardial Scintigraphy with 99mTc-Sestamibi in Children with Kawasaki Disease
Authors: Schillaci Orazio , Banci Maria , Scopinaro Francesco , Tavolaro Rosanna , Villotti Giuseppe , De Vincentis Giuseppe , Ventriglia Flavia , Borgia Maria Clotilde , Centi Colella Antonio , Colloridi Vincenzo 
Published: July 2008

Kawasaki disease (KD) is a systemic vasculitis syndrome of early childhood. It involves particularly the coronary arteries and may cause aneurysms and thrombotic occlusions. Echocardiography is the most useful method of detecting coronary aneurysms. Nevertheless, obstructive lesions are difficult to evaluate and often need invasive coronary angiography. An important feature of this disease is the possibility of finding coronary pathology several years after the onset. This characteristic makes KD an important cause of coronary artery disease (CAD) in young adults. Thus patients with KD and previously diseased coronary arteries should be kept under long-term control. However, coronary angiography is invasive and cannot be performed repeatedly, espe cially in young patients. As an alternative, thallium 201 scintigraphy has been employed, but its low-energy photons are suboptimal for standard gamma-camera imaging, particularly in children aged less than three years. To verify the usefulness of a noninvasive assessment of myocardial perfusion, the authors used rest and dipyridamole 99mTc-Sestamibi scan in 15 children (ranging from one to six years of age) with Kawasaki's cardiac involvement. Coronary aneurysms have been demonstrated by echocardiography in 12 patients; 8 patients were also submitted to cardiac catheterization. The sensitivity of 99mTc-Sestamibi imaging for detection of overall coronary lesions was 88% and the specificity was 93%. These data suggest that rest/dipyridamole 99mTc-Sestamibi scintigraphy is an accurate and noninvasive method for the detection and follow-up of Kawasaki's cardiac damage even in patients aged one year.
Hypertension and Peripheral Arterial Hemodynamics
Authors: Milio Glauco , Cospite Valentina , Cospite Michele 
Published: July 2008

Sixty uncomplicated hypertensive patients (30 stable and 30 borderline) were studied, by strain gauge plethysmography, in comparison with 25 normotensive subjects, in order to evaluate the arterial hemodynamics of the lower limbs in essential hypertension and to verify the different pattern in borderline and in stable hypertensives. Resting blood flow, even if slightly decreased in hypertensive groups, did not show significant differences in its mean values; peak flow, instead, was reduced proportionally to the severity of hypertension in all the hypertensive patients, but only in the stable hypertensives was it statistically significant. Minimal vascular resistance showed a similar behavior: it was significantly increased only in the stable hypertensives, whereas basal vascular resistance was raised in all hypertensive patients and also in the borderline group. Finally, the half-time and the total hyperemic response time, which indicate vascular reactivity, were significantly decreased in all the hypertensives. These results suggest that the stable hypertensive patients develop principally arterial structural changes, while the borderline hypertensive patients have only functional modi fications, such as a reduced compliance and a hyperdynamic condition.
Zero Flow Pressure in Human Coronary Circulation
Authors: Nanto Shinsuke , Masuyama Tohru , Hori Masatsugu , Shimonagata Tsuyoshi , Ohara Tomoki , Kubori Syujiro 
Published: July 2008

Coronary pressure-flow (P/F) relationship has been investigated mainly from the viewpoint of coronary resistance. However, recent experimental evidence suggests that the zero flow pressure intercept (Pzf) provides important characteristics of coronary circulation. Although Pzf is likely to provide meaningful information about characteristics of coronary circulation, no data are available about Pzf in humans. The authors attempted to determine Pzf in humans by analyzing P/F relationship during long cardiac pause. This relationship, provoked by intracoronary adenosine triphosphate (ATP) infusion, was analyzed in 9 patients (8 men, 1 woman) with coronary heart disease (ages: fifty-six ±six years). After the diagnostic cardiac catheterization, ATP, 0.6 mg/3 mL, was administrated by bolus intracoronary injection during measurements of coronary blood flow velocity. Coronary blood flow velocity in the left anterior descending artery was measured with a 0.018-inch Doppler angioplasty guide wire (FloWire, Cariometrics, Inc., Mountain View, Calif.). The dynamic P/F relationship was obtained by correlation of the instantaneous aortic pressure and flow velocity with each other at constant intervals. The least square linear regression analysis was applied to the P/F data to yield the extrapolated Pzf axis. Immediately after intracoronary injection of ATP, long pause (5320 ±1498 msec) appeared and coronary blood flow velocity decreased to 11 ±8 cm/sec. Pzf calculated with P/F relationship was 14 ± 7 mmHg.Conclusions: Thus, the results clearly demonstrate that Pzf is higher than right atrial and left ventricular end-diastolic pressure in humans, indicating the complexity of the determinants of the Pzf.