bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional Evaluation of Coronary Bypass Surgery by Exercise Testing and Oxygen Consumption
Authors: GUINEY TIMOTHY E. , RUBENSTEIN JOEL J. , SANDERS CHARLES A. , MUNDTH ELDRED D. 
Published: June 2012

The short-term effects of coronary bypass surgery were evaluated in 40 male anginal patients with 100% follow-up. Bicycle ergometry was performed pre- and postoperatively (three to eight months). The rate-pressure product (RPP) at angina and 1.0 mm ST segment change was recorded as well as oxygen consumption at the end of each three-minute work load.
All but three survivors (92%) reported symptomatic improvement. Mortality was 5% (2/40). Among survivors morbidity included 29% (11/38) with apparent intra- or perioperative infarctions (new Q waves).

In 20 postoperative patients (50%) neither angina nor ST changes could be elicited when exercised to fatigue. RPP at fatigue was increased an average of 48%. The highest measured oxygen consumption increased an average of 61%. Ten patients (25%) developed angina or ST changes at a higher RPP. O
2
consumption in this group was unchanged (–3%). Five patients (12.5%) had no change or lower RPP at angina or ischemia. Their oxygen consumption was uniformly worse. Three patients (7.5%) were unable to exercise to preoperative RPP levels and could not be assessed. While the majority of revascularized patients are improved, the disparity between symptomatic and functional improvement reinforces the need for objective testing to determine the true effects of bypass surgery.
Internal Mammary Artery Grafts Without Optical Assistance
Authors: LOOP FLOYD D. , SPAMPINATO NICK , SIEGEL WAYNE , EFFLER DONALD B. 
Published: June 2012

Internal mammary artery (IMA) grafts were performed without optical assistance in 175 consecutive patients during a 17-month period. The predominant indications were angina pectoris and the angiographic evidence of a 70% or greater obstruction in one or more major coronary arteries. Eight patients were considered to be in New York Heart Association functional class I, 63 class II, 71 class III, and 33 class IV before the operation. Forty per cent had three major vessels obstructed, and 33% had double vessel disease. IMA grafts were constructed to the anterior descending artery in 151 patients, diagonal branch in 22, and circumflex in two. Two of the 175 and three additional patients had free IMA grafts in the aortocoronary position. Saphenous vein grafts were combined with IMA grafts in 61%. One hospital death occurred, a 0.6% operative mortality.
Late clinical results were analyzed in the first 100 patients. Eighty-four of 99 have had complete remission of angina, and 12 are improved. Repeat arteriograms in 65 patients show 65 of 67 IMA grafts open (97%) and 56 (85%) of 66 saphenous vein grafts patent after an average interval of four months.
These early clinical and angiographic results are encouraging and indicate that the higher IMA patency may result from less size discrepancy between the graft and the coronary artery. The addition of the technically more complicated IMA graft to direct revascularization does not increase morbidity or mortality.
Evaluation of Anticoagulant Therapy in Cloth-Covered Prosthetic Valves
Authors: ISOM O. WAYNE , WILLIAMS C. DAVID , FALK EMILY A. , SPENCER FRANK C. , GLASSMAN EPHRAIM 
Published: June 2012

Over a period of four years, a series of 303 patients had prosthetic valve replacement with the Starr-Edwards cloth-covered metallic ball prosthesis. There were 135 aortic replacements, 105 mitral, 42 combined mitral and aortic, and 21 combined mitral and tricuspid. The frequency of thromboembolism and hemorrhage was studied in patients receiving warfarin sodium (Coumadin) and in those not receiving warfarin.
No thromboemboli occurred during 2,052 patient-months of observation in patients with aortic prostheses who were receiving warfarin, but 10 episodes of hemorrhage occurred. By comparison, after anticoagulants were discontinued, there was 1 episode of thromboembolism during 786 months of patient observation.
Among patients with mitral prostheses who were receiving warfarin, 3 episodes of thromboembolism occurred in 2,081 patient-months of observation, during which 5 hemorrhagic episodes also occurred. By comparison, after warfarin was discontinued, there were 3 episodes of thromboembolism during 402 months.
In patients with mitral and aortic prostheses who were receiving warfarin, 1 episode of thromboembolism occurred in 670 patient-months, and no episodes of hemorrhage. Without anticoagulation, 2 episodes of thromboembolism occurred in 130 patient-months.
In patients with mitral and tricuspid prostheses who were receiving warfarin, there were no episodes of thromboembolism during 186 patient-months, but there was 1 episode of hemorrhage. Without anticoagulation, however, there were 3 episodes of thromboembolism during 32 months of patient observation.
Quantitation of the Normal Frank and McFee-Parungao Orthogonal Electrocardiogram in the Adolescent
Authors: LIEBMAN JEROME , LEE MOO H. , RAO P. SYAMASUNDAR , MACKAY WILMA 
Published: June 2012

A detailed linear, circular and spherical quantitation of the Frank and McFee-Parungao orthogonal electrocardiograms of 166 adolescents is presented.

There are significant differences between pubescent males and females: (1) QRS and T magnitudes in the male are greater than in the female. (2) The difference in magnitudes is greater at age 11-15 than at age 16-19, presumably because females reach puberty earlier. (3) The differences in magnitudes are on the X and Z axes but
not
the Y axis. (4) Males achieve their maximal posterior QRS orientation sooner than females and are more superior as it occurs. (5) The female's T vector is less anterior than the male's. (6) The angular deviation of T from QRS is less in females than males for the horizontal and sagittal planes.

There are significant differences between the two lead systems: (1) The McFee-Parungao's voltages are greater than those of the Frank system. (2) On the X axis, the Frank leftward vector is 62% of the McFee, but the terminal rightward vector is 85% of the McFee. (3) On the Y axis, the Frank inferior vector is 76% of the McFee, but initial superior is 90% and the terminal superior 62% of the McFee. (4) On the X axis, 25% is terminally to the right in the Frank, but only 15% in the McFee. (5) The Frank system is oriented slightly more posterior than the McFee, though the T vectors are not oriented differently.
There is no evidence that the spatial QRS and T orientations are related to each other.
The Influence of Pericardiectomy on the Hemodynamics of Chronic Constrictive Pericarditis
Authors: VIOLA ANGEL R. 
Published: June 2012

Preoperative and postoperative right heart catheterizations were performed on six patients with chronic constrictive pericarditis. Before surgery the patients characteristically showed distinct elevation of right ventricular end-diastolic, pulmonary arterial and wedge pressures. During the operation, right and left ventricular pressure curves were recorded both before and after pericardial resection. Before decortication, the average values of end-diastolic pressures for the right and left ventricles were 17 and 20 mm Hg respectively. No significant changes were observed after pericardiectomy was completed. However, all patients showed excellent clinical recoveries. Postoperative catheterizations performed two to five months after operation disclosed normal intracardiac pressures.
Persistent impairment of ventricular performance in the early period after pericardiectomy must be attributed to a reversible myocardial failure.
Multivariate Analysis of Risk Factors for Coronary Heart Disease
Authors: WILHELMSEN LARS , WEDEL HANS , TIBBLIN GÖSTA 
Published: June 2012

For a prospective study of risk factors for coronary heart disease (CHD), defined as acute nonfatal myocardial infarction and acute fatal CHD, 973 men, all aged 50 years, were recruited from a general Swedish urban population. Of the 855 who agreed to participate, 834 who showed no signs of CHD were selected and observed for nine years and four months. Autopsies were performed on all except two of the 55 patients who died during the study. Forty-four men developed clinical manifestations of CHD during this time; 19 of them died.
Using a multiple logistic model, we analyzed nine probable risk factors. The presence of high serum cholesterol, smoking, high systolic blood pressure, dyspnea, and registration by the Temperance Board increased the risk of events related to CHD significantly. The presence of high serum triglycerides, high hematocrit readings, and increased geographic mobility did not cause a significant increase in events related to CHD. Those with sedentary jobs showed a slightly increased tendency to develop manifestations of the disease.
The predictive power of the logistic function (with cholesterol, smoking, and systolic blood pressure) was tested in another randomly selected population sample of 5,146 men aged 51-55 years and found to be very accurate. The 10% (decile) of the population that had the highest risk of clinical manifestations of coronary disease and the 10% who had the lowest risk were defined. Manifestations of coronary disease occurred 29 times more frequently in the highest decile than in the lowest decile.
Plasma Volume Prior to and Following Volume Loading During Shock Complicating Acute Myocardial Infarction
Authors: LUZ PROTASIO L. DA , WEIL MAX HARRY , LIU VINNIE Y. , SHUBIN HERBERT 
Published: June 2012

Blood volume was measured following onset of shock in 19 patients who had sustained acute myocardial infarction. The plasma volume was measured by dilution technique utilizing R
125
ISA and the red cell mass by (
51
Cr) red cell tag, at the time of admission.

The plasma volume in six survivors was 41.1 ± 3.3 ml/kg; in 13 fatal cases it was 44.7 ± 4.0 ml/kg; this difference was not significant. The red cell mass in four survivors was 27.2 ± 1.75 ml/kg and in four fatal cases, 24.7 ± 1.60 ml/kg. Since these measurements are within normal ranges, we excluded absolute hypovolemia as a significant factor in accounting for the circulatory failure. Infusion of fluids in amounts which maintained a positive fluid balance selectively increased the plasma volume (57.1 ± 4.4 ml/kg), cardiac index, stroke volume and central blood volume in survivors, and reversed arterial vasoconstriction and lactic acidosis. However, the plasma volume was unaffected in the fatal cases (44.4 ± 4.0 ml/kg) and this was associated with progressive hemodynamic and metabolic deterioration.
These observations support the hypothesis that recovery from shock is associated with expansion of plasma volume. To the contrary, during fatal progression of shock, plasma volume expansion does not occur despite volume loading.
The Significance of Second Degree Atrioventricular Block and Bundle Branch Block
Authors: DHINGRA RAMESH C. , DENES PABLO , WU DELON , CHUQUIMIA RUBEN , ROSEN KENNETH M. 
Published: June 2012

His bundle (H) electrograms were recorded in 15 patients with second degree atrioventricular (A-V) block and bundle branch block and these patients were prospectively followed. Site of block was proximal to H in four (BPH), distal to H in nine (BDH), and undetermined in two (studied during 1:1 conduction). Surface electrocardiographic features were retrospectively examined to determine the value of these recordings in predicting the site of block. Patients with type I block, with or without type II or 2:1 block, had BPH. Patients with type II block, 2:1 block, or type II combined with 2:1 block had BDH. Heart failure was more common in those with BPH (three of four patients as compared to three of nine patients with BDH). Syncope developed more commonly in patients with BDH (six of nine patients) as compared to those with BPH (one of four patients). Permanent pacing was indicated in three of four patients with BPH, nine of nine patients with BDH, and one of two patients with block at undetermined site because of syncope or heart failure. Five of nine patients with BDH required pacemakers within ten days of initial admission.
Most patients with second degree A-V block and bundle branch block will need permanent pacing. In patients with 2° BDH, pacemakers are indicated whether or not symptoms are present because of high risk of syncope and potential risk of sudden death. In asymptomatic patients with 2° BPH, careful observation is indicated.
The Significance of Coronary Calcification Detected by Fluoroscopy
Authors: BARTEL ALAN G. , CHEN JAMES T. , PETER ROBERT H. , BEHAR VICTOR S. , KONG YIHONG , LESTER RICHARD G. 
Published: June 2012

Cardiac fluoroscopy to detect coronary calcification was performed on 360 patients before undergoing coronary arteriography for proven or suspected coronary artery disease. Among the 154 patients in whom coronary calcification was identified, 97% had significant coronary disease angiographically (≧ 70% stenosis). In this group, the distribution of one, two, and three vessel coronary disease was 9%, 25%, and 66% respectively. The prevalence of coronary calcification increased with age and severity of coronary disease, but no difference in males versus females was demonstrable. The angiographic severity of coronary disease increased with multiple vessel calcification; three vessel disease occurred in 45%, 66%, and 82% of patients with one, two, and three vessel calcification, respectively. Patients with hyperlipidemia or hypertension had no significant difference in the prevalence of coronary calcification. Among the 267 patients with significant coronary lesions, 56% had calcification detected by fluoroscopy.
Five of the 93 patients with no significant coronary disease angiographically had coronary calcification fluoroscopically. Four of the five had a prior history of myocardial infarction, and two showed asynergy on left ventriculography.
This study demonstrates that cardiac fluoroscopy is a valuable procedure for detecting significant coronary artery disease since this highly specific test is easily performed, inexpensive, noninvasive, and widely applicable for screening large patient populations.
Surgery for Mitral Stenosis
Authors: BLAND EDWARD F. 
Published: June 2012

The renewed interest in surgery for mitral stenosis is reviewed and the progress of the past five years summarized. The present status of the indirect operation (pulmonary-azygos shunt) is discussed, and the notable advances with the direct attack (finger-fracture valvuloplasty and commissurotomy) have been brought up to date (May 1951) by means of a survey of selected centers here and abroad.
Detailed information is available on 352 patients who have had an operation on the mitral valve. It is quite likely that the total now approaches 500 cases.
The over-all operative mortality has been 15 per cent. Post-operative embolism occurred in 6 per cent. Clinical improvement in the majority has been prompt and striking, and this has been fully supported by catheterization data. An appraisal of the more remote effects must await the passage of time.
Those most likely to benefit are patients under the age of 50 with only slight to moderate cardiac enlargement who are nevertheless seriously limited by pulmonary hypertension and congestion.
A formidable procedure of this magnitude should be reserved for those in trouble; it has no place in the management of patients with little or no disability.
Aorticopulmonary Septal Defect Coexisting with Ventricular Septal Defect
Authors: TANDON RAJENDRA , DA SILVA CYRO LUIZ , MOLLER JAMES H. , EDWARDS JESSE E. 
Published: June 2012

Three cases, in each of which an aorticopulmonary septal defect (AP window) coexisted with a ventricular septal defect, are described. In two the ventricular septal defect was of the usual variety, and in one it was part of the tetralogy of Fallot.
The patients presented as examples of congestive cardiac failure with a large left-to-right shunt in infancy. Aortography was the most reliable method for identification of the AP window when a ventricular septal defect was associated. Associated features included a right aortic arch with mirror image branching in the first case and tetralogy of Fallot with muscular subaortic stenosis in the third case. In the case with the tetralogy of Fallot, the effects of pulmonary stenosis were masked by the left-to-right shunt through the AP window.
The Effect of Aortocoronary Bypass Grafts on Myocardial Blood Flow Reserve and Treadmill Exercise Tolerance
Authors: KNOEBEL SUZANNE B. , MCHENRY PAUL L. , PHILLIPS JOHN F. , LOWE DANIEL K. 
Published: June 2012

Twenty-five patients had myocardial blood flow reserve determinations (percentage increase in myocardial blood flow with stress), treadmill exercise tests and coronary and bypass cineangiography pre- and postaortocoronary bypass surgery. Twenty of the patients had the postoperative studies performed three months after operation, three at two months and two at five and six months, respectively.
Eleven of the 25 patients had all significant coronary artery obstructions (75% or greater) bypassed and all grafts were open at the time of restudy. Preoperatively, blood flow reserve had been abnormal in nine and all had positive treadmill tests. Postoperatively, all eleven patients had normal myocardial blood flow response to stress and treadmill tests were negative in ten (one patient was not restudied on the treadmill).
In six patients, no patent grafts could be demonstrated. These patients continued to show abnormal blood flow reserve and positive treadmill studies.
Eight of the 25 patients had partial revascularization in that some grafts were open, some closed, and some significantly occlusive lesions were not bypassed. Four of these eight patients had normal flow and treadmill studies and the remainder continued to have an abnormal response to one or both of the measurements.
The relationship between treadmill exercise response, myocardial blood flow reserve, and graft patency was significant at the 0.005 level for patients with all grafts open or closed. No significant correlation was obtained between any of the measurements in those patients with partial revascularization.
The data indicate that successful aortocoronary bypass grafting provides myocardial revascularization as reflected in a return to normal of the myocardial blood flow reserve and response to treadmill stress testing.
Adolescent Hypertension
Authors: KILCOYNNE MARGARET M. 
Published: June 2012

Two groups of patients were recognized among 27 black and latin adolescents who underwent diagnostic evaluation for hypertension. Group I consisted of ten patients, seven of whom had arterial pressures consistently higher than 1 standard deviation above the pressure means of normal adolescents and three had pressures below this level. Group II consisted of 17 patients, 16 of whom had systolic and diastolic pressures greater than 2 standard deviations above the means for their age-sex group. One patient had solely systolic hypertension. An assignable cause for their hypertension was not apparent. Chemical parameters, including plasma renin activity (radioimmunoassay Angiotensin I), were similar to those observed in adult hypertensive patients of the same community. A difference in response to therapy was noted in adolescents compared to adults which may imply differences in the mechanisms involved at this phase of the disease, as has been reported in patients with labile and early hypertension and spontaneously hypertensive rats.
At least three facets of this adolescent hypertension study deserve implementation and investigation: 1) routine blood pressure measurements in high schools, 2) longitudinal evaluation of the indications for and effects of therapy, and 3) intensive inquiry into the hemodynamic and neurohumoral aspects of hyperten- sion in its early unfolding.
Internal Mammary Artery Versus Autogenous Vein for Coronary Artery Bypass Graft
Authors: ROSSITER STEPHEN J. , BRODY WILLIAM R. , KOSEK JON C. , LIPTON MARTIN J. , ANGELL WILLIAM W. 
Published: June 2012

Aortocoronary venous graft (ACVG) and internal mammary artery graft (IMAG) are currently the two most popular choices for coronary artery bypass. The morphologic alteration and susceptibility to atheromatous degeneration of the IMAG were compared with the ACVG. Six of 12 surviving dogs with IMAGs were fed a hyperlipidemic diet and six were placed on a regular diet. All dogs were sacrificed 3-15 months after surgery. Twelve of 28 long-term surviving dogs with ACVGs were also on hyperlipidemic diets, and all were sacrificed 3-18 months after surgery. Arteriography and electron microscopy were performed in selected cases, and histology was performed in all cases. All long-term IMAGs remained patent; 83 percent (5/6) "regular" diet arteries were normal, with no intimal proliferation, while 33 percent (2/6) "hyperlipidemic" IMAGs had diffuse atheroma. Eighty-two percent of ACVGs revealed significant atherosclerosis. Severity of arteriosclerotic involvement of the ACVG was far greater than that of the native coronary circulation; this was not true for the IMAG.
It may be concluded that (1) in the normolipidemic condition the IMAG undergoes significantly less severe histologic change than the ACVG, (2) both the IMAG and the ACVG are more susceptible to atheromatous change than the native coronary circulation. In these series, patency was not influenced by severity of histologic changes, and no grafts were occluded by virtue of the arteriosclerotic process.
Interfacial reactivity of radionuclides: emerging paradigms from molecular-level observations
Authors: Felmy A. R. , Ilton E. S. , Rosso K. M. , Zachara J. M. 
Published: June 2012

AbstractOver the past few decades an increasing array of molecular-level analytical probes has provided new detailed insight into mineral and radionuclide interfacial reactivity in subsurface environments. This capability has not only helped change the way mineral surface reactivity is studied but also how field-scale contaminant migration problems are addressed and ultimately resolved. Here we review relatively new interfacial reactivity paradigms and assess their implications for future research directions. Specific examples include understanding the following: the role of site-to-site electron conduction at mineral surfaces and through bulk mineral phases and the effects of local chemical environment on the stability of intermediate species in oxidation-reduction reactions and the importance of mechanistic reaction pathways for defining possible reaction products and thermodynamic driving force. The discussion also includes examples of how detailed molecular/microscopic characterization of field samples has changed the way complex contaminant migration problems are conceptualized and modelled.