bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Procaine Amide, Quinidine, and Ajmaline in the Wolff-Parkinson-White Syndrome
Authors: WELLENS HEIN J.J. , DURRER DIRK 
Published: June 2012

Using the single test stimulus method, atrioventricular (A-V) conduction, ventriculo-atrial conduction, the refractory period of right atrium and right ventricle, and the mechanism of tachycardia were studied in 16 patients with the Wolff-Parkinson-White syndrome. The same studies were repeated at least four times during the hour following intra-atrial administration of 10 mg procaine amide/kg body weight (six patients), 4 mg quinidine gluconate/kg body weight (six patients), or 50 mg ajmaline (four patients).
Following procaine amide the refractory period of the accessory pathway increased in all patients, with temporary complete block of the accessory pathway in four patients. There was an increase in H-V interval during antegrade conduction through the A-V node-His pathway. The effective refractory period of the A-V node showed no appreciable change. In three of four patients tachycardia could not be produced by pacing in contrast to the pacing effect found prior to procaine amide.
Quinidine gluconate increased the refractory period of the accessory pathway in four patients, causing temporary complete block in two patients. The H-V interval increased in three patients. The refractory period of the A-V node showed no change in three patients, lengthened in one, and shortened in the other two. Quinidine gluconate prevented pacing-induced initiation of tachycardia in two out of four patients.

Ajmaline
*
increased the refractory period of the accessory pathway in all four patients, with temporary complete block in three patients. The H-V interval also lengthened. No change was observed in the refractory period of the A-V node. Ajmaline prevented initiation of tachycardia in one out of two patients. In the other patient tachycardias could still be initiated despite disappearance of pre-excitation during atrial pacing.

In one patient in each group tachycardia could be produced during pacing following drug administration where no tachycardia could be produced under control conditions. In two patients re-entry in the A-V node during ventricular pacing caused this phenomenon. In the other patient administration of the drug prevented atrial re-entry during atrial pacing. This re-entrant beat had previously created refractoriness in the atrial part of the tachycardia pathway. The changes following procaine amide, quinidine gluconate, and ajmaline were clearly short term; their effects disappeared after one hour in 15 of the 16 patients studied.
Accelerated Junctional Escape
Authors: KNOEBEL SUZANNE B. , FISCH CHARLES 
Published: June 2012

During the routine interpretation of electrocardiograms, 49 cases of spontaneously occurring accelerated, or borderline accelerated, junctional escape complexes (escape intervals of 1200 ± 20 msec) were encountered. Forty-seven of the 49 patients whose cardiograms demonstrated the accelerated junctional escapes had the clinical setting recognized to be associated with the more protracted accelerated junctional rhythm, nonparoxysmal junctional tachycardia. In addition, five patients demonstrated nonparoxysmal junctional tachycardia immediately preceding or subsequent to the cardiograms demonstrating accelerated junctional escape. It is suggested, therefore, that the two arrhythmias, i.e., accelerated junctional escape and nonparoxysmal junctional tachycardia, may be of similar clinical significance.
The determinants of the length of the manifest escape interval could be assessed in those cases where two or more junctional escape complexes occurred in sequence, allowing the true interectopic interval to be ascertained. The dominant role of the rate of atrioventricular conduction and the sequence of ventricular and junctional activation in determining the length of the manifest escape interval was apparent.
Criss-Cross Atrioventricular Relationships Producing Paradoxical Atrioventricular Concordance or Discordance
Authors: ANDERSON ROBERT H. , SHINEBOURNE ELLIOT A. , GERLIS LEON M. 
Published: June 2012

Two cases are described in which the systemic and pulmonary blood streams cross at atrioventricular level. One was examined pathologically, the other was diagnosed at cardiac catheterization by angiography. Both possessed situs solitus, but in one heart the right atrium was connected to a morphologic right ventricle on the left, whereas in the other it was connected to a left-sided morphologic left ventricle. In both cases transposition of the great arteries was present. The cases have been interpreted as representing rotation of embryonic d- and l-bulboventricular loops following septation.
In attempting to describe these heart difficulties in terminology were encountered which were partially overcome by combining the concepts of concordant and discordant atrioventricular relationships with those of transposition and malposition. However, to give an accurate interpretation of the hearts, it proved necessary to include a term indicating rotation of the bulboventricular loop following septation. Thus the hearts were described as situs solitus, discordant (d-rotated) loop with d-transposition, and situs solitus, concordant (l-rotated) loop with l-transposition.
Shape and Volume Changes During "Isovolumetric Relaxation" in Normal and Asynergic Ventricles
Authors: RUTTLEY MICHAEL S. , ADAMS DOUGLASS F. , COHN PETER F. , ABRAMS HERBERT L. 
Published: June 2012

Clinically suspected coronary artery disease was assessed in 52 patients by 16-mm biplane left ventriculography. Outward movement of the left ventricular wall was observed prior to mitral valve opening in normal patients and those with coronary artery disease. In the normal ventriculogram, outward movement was usually visible in the anterior wall and the apex. In the asynergic ventricle, the outward movement almost invariably occurred at the region of optimal contraction. Outward movement of the ventricular wall during protodiastole and isovolumetric relaxation was accompanied by a significant volume increase over the end-systolic volume. The volume increase was greater in the abnormal than in the normally contracting ventricle.
The altered ventricular volume was probably associated with the return to the ventricle of blood contained between the patent aortic leaflets at the end of ventricular ejection. This event occurs during aortic valve closure when ventricular pressure is falling more rapidly than aortic pressure. It accounts for the alteration in volume between end ejection and pre-mitral valve opening.
The stroke volume, which is generally calculated from end-systolic and end-diastolic volumes, may therefore be inaccurate by at least 10% because ventricular volume immediately before mitral valve opening is not utilized in the calculation. Some of the discrepancies between angiocardiographic stroke volume and ejection fraction measurements and those obtained by other methods may be explained by failure to use preinflow volume (PIV) in the calculations.
The Progression of Arteriosclerosis
Authors: CHILVERS A. S. , THOMAS M. LEA , BROWSE N. L. 
Published: June 2012

This paper reports the results of a study made on 25 patients who have had two or more translumbar aortograms at intervals varying from one to four years. A technique was devised for the measurement of the diameter of the vessels from the radiographs and the type of atherosclerosis was also classified. The arterial tree, from the lower abdominal aorta to the division of the popliteal artery, was divided into nine anatomical segments. A total of 324 segments were studied.
The results show that atherosclerosis must not be assumed to be a progressive and exclusively stenotic disease. In 30% the aorta and common iliac arteries became wider and in another third they showed no change. Fifty percent of the ilio-femoral segments became longer and most of these also became wider, which suggests that a considerable proportion of patients will ultimately develop arteriomegaly. In the superficial femoral arteries 50% of the cases developed further narrowing.
Short narrow segments did not all progress to occlusion — 40% of the short stenoses in the aorta and iliac arteries became 2 to 5% wider. Long narrow segments more often became occluded, especially in the superficial femoral artery.
It is concluded that arteriosclerotic degeneration is just as often a disease of dilatation as narrowing and that the only way to obtain evidence upon which to base a long-term prognosis is to repeat arteriograms over a period of years.
Ectopic Ventricular Prematurity and Its Relationship to Ventricular Tachycardia in Acute Myocardial Infarction in Man
Authors: DE SOYZA NEIL , BISSETT JOE K. , KANE JAMES J. , MURPHY MARVIN L. , DOHERTY JAMES E. 
Published: June 2012

In order to determine the role of the coupling interval of a premature ventricular contraction (PVC) in the development of paroxysmal ventricular tachycardia (PVT) during the early phase of acute myocardial infarction in man, 52 male patients with documented acute myocardial infarction had 24-hour Holter monitoring commenced within 24 hours of the onset of prolonged chest pain. Review of the tape recordings revealed that 27 patients had PVT documented, while 25 patients did not. Analysis of the data on the two groups showed that the frequency of PVCs, coupled PVCs, and accelerated idioventricular rhythm (AIVR) were found to be associated with a significantly increased incidence of ventricular tachycardia.
The mean coupling interval of the PVCs initiating episodes of ventricular tachycardia was not significantly different from either the mean coupling interval of the isolated PVCs in the patients with PVT or the mean coupling interval of the PVCs in the patients without PVT. This suggests that the coupling interval of a ventricular ectopic is a poor predictor of ventricular tachycardia in the early phases of acute myocardial infarction.
Role of Autonomic Nervous System in the Pathogenesis of Prinzmetal's Variant Form of Angina
Authors: YASUE HIROFUMI , TOUYAMA MASATO , SHIMAMOTO MITSUOMI , KATO HIROFUMI , TANAKA SATORU , AKIYAMA FUMIYA 
Published: June 2012

In ten patients with Prinzmetal's variant form of angina the effects of various drugs were assessed: subcutaneous injection of methacholine (10 mg), atropine (0.7 mg), and epinephrine (0.7 mg); intravenous infusion of isoproterenol (20-25 µg/min); and in the three of the above patients who were having recurrent spontaneous attacks at the time of the examination, oral administration of atropine (0.6-1.2 mg), propranolol (30-90 mg), and phenoxybenzamine (10 mg in one patient). Master's triple two-step test and selective coronary arteriography were done on all the patients.
In the three patients who were having spontaneous attacks at the time of the examination, the administration of methacholine induced the attacks and that of atropine suppressed the attacks. Epinephrine induced the attacks in two patients and propranolol was without effect in suppressing the attacks. Phenoxybenzamine (in one patient) suppressed the attacks. Neither Master's triple two-step test nor isoproterenol infusion precipitated the attacks, though heart rate increased to more than 110 beats/min and 160 beats/min respectively in all the patients. Coronary arteriograms were normal in seven of the ten patients.
It is concluded that enhanced activity of the parasympathetic nervous system, which occurs at rest, is involved in the initiation of the attack by stimulating the sympathetic nerve which in turn probably induces coronary arterial spasm by way of activating alpha (vasoconstrictor) receptors present in the large coronary arteries.
Clofibrate Reversal of Platelet Hypersensitivity in Hyperbetalipoproteinemia
Authors: CARVALHO ANGELINA C. A. , COLMAN ROBERT W. , LEES ROBERT S. 
Published: June 2012

Platelet function was evaluated in 29 patients with familial hyperbetalipoproteinemia; 17 were untreated and 12 were receiving clofibrate (Atromid-S). In comparison with 26 normal subjects, the untreated patients aggregated in response to 1/3 the concentration of adenosine diphosphate (ADP), 1/25 the concentration of epinephrine, and 1/4 the concentration of collagen. Treatment with clofibrate, 2 g daily, returned the ADP sensitivity of the platelets to normal and returned epinephrine and collagen sensitivity towards normal, even though it did not alter total cholesterol, low-density-lipoprotein (LDL) cholesterol, or triglyceride concentrations significantly.
Platelet nucleotide release was also 3-to-5 fold increased in untreated type II patients. Clofibrate treatment failed to diminish the elevated platelet nucleotide release.

Incubation of clofibrate at therapeutic concentrations (100-200 µu/ml) with normal platelets
in vitro
decreased their sensitivity to ADP and epinephrine and reduced
14
C-serotonin release by these agents. The effect on the release was probably mediated through decreased platelet sensitivity since higher doses of epinephrine could reverse the inhibitory effect of clofibrate.

Clofibrate may decrease the incidence of thrombotic complications of atherosclerosis by altering platelet sensitivity to aggregation.
Unusual Longevity in Persistent Common Atrioventricular Canal
Authors: TANDON RAJENDRA , MOLLER JAMES H. , EDWARDS JESSE E. 
Published: June 2012

Five of 139 patients with persistent common atrioventricular canal (AVC) confirmed at necropsy had lived to the age of 46 years or older. The complete type of the malformation was present in one, the transitional type in one and the partial type in three. The oldest of the latter group was 79 years of age at the time of death.
In a study of ages at death among 139 cases of AVC the following observations were made. Of the 91 patients with the complete type of AVC, 37 percent survived more than one year and 17.6 percent more than five years. Of the 48 patients with the transitional and partial types of the defect, 67 percent lived more than one year and 37.5 percent beyond five years.
One of our cases was highly unusual in that AVC was associated with corrected transposition.
The Effects of Transfemoral Catheterization on Blood Flow in the Extremities
Authors: VYDEN JOHN K. , NAGASAWA KOICHI , GRAETTINGER WILLIAM , MARCUS HAROLD S. , GROSETH-DITTRICH MARSHA , SWAN H. J.C. 
Published: June 2012

The peripheral hemodynamics of 20 patients were studied 24 hours before and 24 hours following completion of Seldinger transfemoral cardiac catheterization. All patients were catheterized in the right femoral artery and vein, while in 13 an arterial needle was placed in the left femoral artery.
In the catheterized leg, mean calf blood flow and venous capacitance fell while mean calf vascular resistance was increased. The placement of an indwelling arterial needle caused mean calf blood flow to fall with an increase in calf vascular resistance. Venous capacitance was unchanged. The above changes while present 24 hours after catheterization had returned to normal one week later. While no symptoms or signs of limb ischemia occurred, oscillometry showed deterioration in the lower limb pulsation amplitudes in 13 of the 20 patients. No significant changes in peripheral hemodynamics were seen in the limbs, the arteries of which had not been catheterized.
Thus, although all patients were symptomless and free of signs suggestive of ischemia clinically, arterial and venous catheterization and/or the placement of an arterial needle causes significant changes which last at least 24 hours distal to the invasion of the vessels.
Adolescent Hypertension
Authors: KILCOYNE MARGARET M. , RICHTER RALPH W. , ALSUP PEGGY A. 
Published: June 2012

Blood pressure screening of 3537 high school students in the Harlem community was performed to determine the frequency distribution of blood pressures in this age group and to investigate the prevalence of hypertension in adolescence. The major inscription of the frequency distributions of both systolic and diastolic blood pressures was comparable among black, latin, and white students. However, female students of all races had lower systolic pressures than males. An over-all prevalence of 5.4% systolic and 7.8% diastolic hypertension was observed during the initial screening, and no significant difference in prevalence among the races was detected. With follow-up screening of those students with elevated blood pressures (BP ≧ 140/90 mm Hg) prevalence declined markedly to 1.2% systolic and 2.4% diastolic hypertension and showed that black males had a higher prevalence of persistent diastolic hypertension (3.7%) than all other groups. This difference did not achieve statistical significance; however, the racial comparison was not wholly satisfactory because of the limited sample of white students. Nevertheless, the observed prevalence in black males was more than twice that reported in the National Health Survey during a single screening.
The data suggest two features of adolescent blood pressure which should be taken into account in hypertension detection programs for this age group: 1) the criteria selected to define blood pressure elevations in a maturing circulation would be more meaningful if related to the observed frequency distributions of blood pressure in an adolescent sample population. Values exceeding one standard deviation above the means reported herein are recommended (males: 132/85 mm Hg; females: 123/82 mm Hg); and 2) serial measurements of blood pressure appear to be required to detect the potentially hypertensive adolescent as well as to determine prevalence rates with accuracy.
A finding which deserves further study is the striking increase in the percent of elevated blood pressures noted between the ages of 17 and 18 years, particularly in black males. Black males represent a vulnerable segment of the adult hypertensive population as well.
The results indicate that over-all, contrary to traditional views, the development of hypertension may begin in adolescence and that methods of detection which appear satisfactory in adulthood are insufficient to uncover the true prevalence rates of hypertension in this age group.
Aberrant Coronary Artery Origin From the Aorta
Authors: LIBERTHSON RICHARD R. , DINSMORE ROBERT E. , BHARATI SAROJA , RUBENSTEIN JOEL J. , CAULFIELD JAMES , WHEELER EDWIN O. , HARTHORNE J. WARREN , LEV MAURICE 
Published: June 2012

Twenty-one patients with anomalous coronary artery origin from the aorta are discussed, and the cases reported in the literature are reviewed. The left anterior descending (LAD) and left circumflex (Cx) arteries arose aberrantly from the right sinus of Valsalva of the aorta (RSV) in six patients. In four of these patients the connecting branch from the anomalous origin passed anterior to the aorta and the right ventricular in-fundibulum (RVinf), and in two patients, this branch passed between the aorta and RVinf. In 11 patients only the Cx was aberrant, and arose either from the RSV directly or from the right coronary artery (RCA), and passed posterior to the aorta and RVinf. In four patients the RCA arose aberrantly — in three from the left sinus of Valsalva of the aorta passing anteriorly, and in one from the left Cx passing posteriorly.
Aberrant coronary artery origin from the aorta had clinical consequences only when the branch connecting the LAD and Cx to the RSV passed between the aorta and RVinf. Both our findings and those reported in the literature associate this variant with exertional sudden death in young persons. Anomalous coronary patterns can be delineated readily by selective coronary cineangiography, and as illustrated, the right anterior oblique projection can readily distinguish those prone to sudden death from the clinically insignificant variants. The former can be corrected with coronary artery bypass surgery.
Pathways and Functional Significance of the Coronary Collateral Circulation
Authors: LEVIN DAVID C. 
Published: June 2012

Two hundred coronary arteriograms and left ventriculograms of patients having significant coronary artery disease were reviewed. Collateral circulation was seen only when the degree of arterial narrowing exceeded 90%. Ten different collateral pathways were noted in patients having right coronary obstruction; seven different pathways were noted in left anterior descending obstruction; five different pathways were noted in left circumflex obstruction.
The role of collateral circulation in preserving myocardial function was assessed by comparing regional left ventricular contractility in 86 instances of total arterial occlusion and adequate collateral circulation with that in 80 instances of total arterial occlusion and inadequate collateral circulation. Among the group with adequate collaterals, regional left ventricular contraction was normal in 43%, mildly impaired (hypokinetic) in 52% and severely impaired (akinetic or dyskinetic) in only 5%. Among the group lacking adequate collaterals, regional contraction was normal in 11%, mildly impaired in 16% and severely impaired in 73%. Chi square analysis reveals that the difference between the two groups is significant at the .01 level. These data indicate that collateral circulation plays an important role in preserving myocardial contractility in patients with coronary artery disease.
Right Aortic Arch
Authors: KNIGHT LAURA , EDWARDS JESSE E. 
Published: June 2012

An analysis was made of 78 pathologic specimens in which a right aortic arch was present. In four, the right arch was part of a double aortic arch. In 74 cases the right aortic arch was the only arch. The cases of right aortic arch could be subdivided into two groups as follows: (1) that with a retroesophageal aortic segment (three cases) and (2) that without a retroesophageal segment (71 cases).
The latter cases could be subdivided according to the nature of the origin of the branches of the arch as follows: (1) mirror image branching (60 cases), (2) aberrant left subclavian artery (ten cases) and (3) isolation of left subelavian artery (one case).
Congenital heart disease, of which the tetralogy of Fallot was the most common, was observed in each of the cases of right arch without retroesophageal aortic segment. Such an association was seen in one of three cases of right aortic arch with retroesophageal aortic segment and in three of the four cases of double aortic arch.
The potential for significant tracheal and esophageal obstruction is present in double aortic arch, in right aortic arch with retroesophageal segment and in right aortic arch without retroesophageal segment but with an aberrant left subelavian artery. In the latter condition, significant esophageal and tracheal compression depends upon the presence of a left-sided ductus arteriosus. This state was observed in five of ten cases with right aortic arch and aberrant left subelavian artery.