bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetric Left Ventricular Contraction in Patients with Previous Myocardial Infarction
Authors: GENTZLER RICHARD D. , GAULT JAMES H. , HUNTER A. STEWART , LIEDTKE A. JAMES , LEAMAN DAVID M.
Published: June 2012

The possibility was considered that the presence and magnitude of asymmetry of left ventricular (LV) contraction in patients with previous myocardial infarction (MI) could be determined from volume and dimensional characteristics of contraction derived independently from the frontal (AP) and lateral (LAT) views of biplane cineangiograms. Accordingly, regression analyses were determined from biplane cineangiograms in 18 patients without MI to compute end-diastolic (EDV) and end-systolic (ESV) volumes in the AP and LAT views (V
biplane
= 1.03V
calc
AP-7.7 ml,
r
= 0.989, SEE = 8.7 ml; V
biplane
= 0.85V
calc
LAT+5.9 ml,
r
= 0.99, SEE = 8.2 ml). Comparative measurements of EDV, stroke volume (SV), and ejection fraction (EF) in these patients were identical in AP and LAT films, with a small random error (EDV
AP
= 136.7 ± 13.0 ml; EDV
LAT
= 136.7 ± 13.4 ml; SEE for SV = ± 13.0 ml ( ± 16%), SEE for EF= ± 0.03 ( ± 5%). In 20 patients with MI EDVs calculated from AP and LAT films were also identical (189.9 ± 18.1 ml and 184.2 ± 17.1 ml, respectively). However, SV exhibited substantial variation between the two views (SV
AP
= 76.7 ± 5.5 ml and SV
LAT
= 51.5 ± 4.7 ml,
P
< 0.001), as did EF (EF
AP
= 0.45 ± 0.03 and EF
LAT
= 0.31 ± 0.03,
P
< 0.001). In addition, directly measured extent of LV minor circumferential shortening was comparable in AP and LAT films in patients without MI (5.15 ± 0.50 cm and 5.25 ± 0.47 cm, respectively), while in patients with MI these measurements differed significantly (4.74 ± 0.41 cm and 2.73 ± 0.31 cm, respectively;
P
< 0.001). It is concluded that a systematic error will result when estimates of SV and EF, as well as mean circumferential fiber shortening rate, are derived from single plane cineangiograms in patients with MI.
Total Correction of Tetralogy of Fallot in Infancy
Authors: SUNDERLAND CECILLE O. , MATARAZZO RUTH G. , LEES MARTIN H. , MENASHE VICTOR D. , BONCHEK LAWRENCE I. , ROSENBERG JACK A. , STARR ALBERT
Published: June 2012

Total intracardiac repair of symptomatic tetralogy of Fallot was accomplished in twenty-nine infants under two years of age with a mortality of six per cent. All twenty-seven survivors are asymptomatic. Postoperative hemodynamic evaluation of 17 randomly selected children was performed at least 12 months following surgery. Pulmonary regurgitation was present in 12 of the 17 children but was well tolerated, with only minimal cardiac enlargement and in no case were there symptoms or important hemodynamic consequences. Growth of the pulmonary artery with respect to the aorta occurred. Normal left ventricular performance was indicated by normal ejection fraction and normal systemic arterial pressure. Intellectual and social development were indistinguishable from a "normal" group of randomly selected children as assessed by detailed psychological testing.
An Analysis of 35 Cases of the Complete Form of Persistent Common Atrioventricular Canal
Authors: TENCKHOFF LORE , STAMM STANLEY J.
Published: June 2012

Thirty-five hearts with the complete form of persistent common atrioventricular canal were classified according to the morphology of the common anterior leaflet. The ratio of specimens with a free-floating undivided common anterior leaflet (Type I) to those with a divided common anterior leaflet attached to the septum (Type II) was 1:2. Type I cases had a high incidence of other cardiac (90 percent) and noncardiac (80 percent) malformations. These were primarily conotruncal anomalies (80 percent), left ventricular outflow obstructions (66 percent), aortic arch hypoplasia (30 percent), and abnormalities of organ position or symmetry including the polysplenia and asplenia syndromes. In contrast, Type II canals exhibited a high incidence of Down's syndrome (40 percent), other cardiac and noncardiac anomalies being less common. The associated anomalies suggest that Type I lesions reflect an earlier interference during embryogenesis than Type II lesions.

A clockwise QRS loop and a normal or right axis on the electrocardiogram in four cases were associated with a left ventricular inflow tract of normal length, suggesting that conduction system displacement and a deficient base of the heart may be interrelated.

Postmortem double contrast radiography confirmed the angiographic differences between Type I and II lesions, and in Type I lesions clarified the alterations in the angiographic profile occurring with variations in the fullness of the common anterior leaflet.
Effect of Treatment on Morbidity in Hypertension. Veterans Administration Cooperative Study on Antihypertensive Agents
Authors: POBLETE P. F. , KYLE M. C. , PIPBERGER H. V. , FREIS E. D.
Published: June 2012

Electrocardiographic (ECG) data are presented from the Veterans Administration Cooperative Study of 143 nontreated and 137 treated male patients with initial diastolic blood pressures averaging 90-114 mm Hg. Average follow-up was 2.9 years and longest follow-up was 5 years. Significant differences were observed with respect to the ECG signs of left ventricular hypertrophy (LVH). In the patients not meeting criteria for LVH prior to randomization, the incidence of abnormal QRS voltage, ST-segment depression or T wave flattening or inversion developing in the treated patients was approximately one-fourth that found in the control group. In the patients with ECG evidence of LVH prior to randomization, the reversion to normal of QRS voltage or ST-segment depression was approximately 2.5 times greater in the treated than in the control patients. Although no significant effect of treatment was observed on other ECG changes such as Q and QS patterns, A-V or ventricular conduction defects or arrhythmias, the incidence of such events was too low to make valid comparisons. However, the present results indicate that antihypertensive drug treatment markedly improved the ECG changes specifically related to hypertension.
Left Ventricular Wall Motion During the Isovolumic Relaxation Period
Authors: ALTIERI PABLO I. , WILT SHARON M. , LEIGHTON RICHARD F.
Published: June 2012

Technically adequate left ventricular cineangiograms obtained in the 30 degree right anterior oblique (RAO) projection from 100 consecutive patients with chest pain were studied for the presence of left ventricular wall motion during the isovolumic relaxation period. Obstructive coronary artery disease was found in 59 and normal coronary arteries in 41 patients. Systolic contraction abnormalities were present in 52 of the 100 patients. Outward left ventricular wall motion during the isovolumic relaxation period was observed in 83 patients. This outward motion, termed segmental early relaxation phenomenon (SERP), was localized in 81. In 29 patients SERP was accompanied by a simultaneous inward motion that was apparent in the 30 degree RAO position in another part of the left ventricle. In ventricles with systolic contraction abnormalities SERP tended to occur in the normally contracting areas (25 of 39 patients). When the abnormal systolic contraction was extensive, SERP occurred infrequently (4 of 16 patients). In this group of patients with chest pain, whether or not they had coronary artery disease, outward left ventricular wall motion occurred commonly during isovolumic relaxation. It appears to be a normal variation of left ventricular relaxation.
Angiographic-Morphologic Correlation in Patients with Severe Mitral Regurgitation Due to Prolapse of the Posterior Mitral Valve Leaflet
Authors: RANGANATHAN N. , SILVER M. D. , ROBINSON T. I. , KOSTUK W. J. , FELDERHOF C. H. , PATT N. L. , WILSON J. K. , WIGLE E. D.
Published: June 2012

Angiographic-morphologic correlation was done on findings in 16 patients with proven prolapse of the posterior mitral leaflet and severe mitral regurgitation. A triscalloped bulge into the left atrium in the left ventriculogram taken in the right anterior oblique projection is caused by prolapse of all three scallops of the posterior mitral leaflet. The prolapsed middle scallop produces a central bulge, the prolapsed posteromedial commissural scallop a posteroinferior bulge ih tne area of the posteromedial commissure, and the prolapsed anterolateral commissural scallop an anterosuperior bulge in the anterolateral commissural area. The latter is often overlapped by the aortic root but if prominent, juts beyond it. Correlation proved that the diagnosis of individual scallop prolapse in this syndrome can be made accurately despite gross mitral regurgitation.
Waveform Patterns in Frank-Lead Rest and Exercise Electrocardiograms of Healthy Elderly Men
Authors: RAUTAHARJU P. M. , PUNSAR S. , BLACKBURN H. , WARREN J. , MENOTTI A.
Published: June 2012

Waveform patterns of P, ST and T vector functions of Frank-lead rest and exercise vectorcardiograms (VCG) of 375 ostensibly normal males, aged 50-70 years, were evaluated by waveform vector analysis (WVA). This procedure suitably quantified waveform information, providing a stable reduced data base comprising mean vector (MV), gradient vector (GV), convex vector (CV), sigmoid vector (SV), and quaternary vector (QV). In resting VCG, most of the waveform vectors were clustered fairly uniformly in space with tight directional distributions of widely varied magnitudes; normal limits of these magnitudes were established and their spatial frequency distributions mapped. Individual vectors' contributions to the overall waveform pattern of the vector function were quantified with waveform power indices. The GV accounted for >90% of ST waveform power, whereas the CV and GV jointly accounted for about 90% of T waveform and >80% of P wave waveform variation. Exercise elicited significant changes in magnitude and orientation of some vectors. All P wave vectors increased; by an average of 68% in P-MV, 80% in P-GV, 64% in P-CV, and by 41% in P-SV. The P waveform changes were compatible with enhancement of surface potentials associated with excitation of the right atrium. By contrast, T-CV and T-QV decreased slightly. ST-MV shifted clockwise to the right and upward whereas ST-GV rotated in the opposite direction toward inferior and left. ST-segment gradients and the corresponding ST-GV were independent of heart rate, whereas the (conventional) ST slope tended to increase unpredictably with increasing heart rate.
Coronary Artery Anatomy in Left Bundle Branch Block
Authors: DE MOTS HENRY , RÖSCH JOSEF , RAHIMTOOLA SHAHBUDIN H.
Published: June 2012

It has previously been reported that the length of the left main coronary artery is short in patients with left bundle branch block (LBBB) and that an unexpectedly large number of LBBB patients had dominant left coronary arterial distribution. The present coronary arteriographic study of 13 patients with LBBB revealed a mean length of the left main coronary artery ( ± 1
sd
) of 10.9 ± 6.0 mm, a measurement which was not significantly different (
P
> 0.5) from that of the left coronary arteries in 78 patients in a control group (10.0 ± 3 mm). The arterial distribution patterns showed a contribution of the right coronary artery to the posterior descending artery in 12 of the 13 patients with LBBB. Coronary artery anatomy does not appear related to the presence of LBBB.
Marantic Valvular Vegetations
Authors: WALLER BRUCE F. , KNAPP WILLIAM S. , EDWARDS JESSE E.
Published: June 2012

Marantic valvular vegetations represent one form of vegetative nonbacterial endocarditis. While any of the cardiac valves may be involved, the mitral valve and/or aortic valve are the most common sites at which this process occurs. Underlying disease of a chronic nature is usually identifiable somewhere in the body, with malignant tumors collectively representing the most common underlying condition. Systemic arterial occlusion, usually multiple when present, may antedate the identification of an underlying malignant tumor.

The gross nature of the vegetations requires histologic distinction from metastatic lesions of valves and from bacterial endocarditis. In some instances, the latter process may originate upon marantic vegetations.
Epicardial Mapping in a Variant of Type A Wolff-Parkinson-White Syndrome
Authors: NEUTZE JOHN M. , KERR ALAN R. , WHITLOCK RALPH M. L.
Published: June 2012

Electrocardiographic and epicardial mapping studies are reported in a child with an atrial septal defect and a variant of type A Wolff-Parkinson-White (WPW) syndrome. The vectorcardiogram suggested a posterior area of early activation and this was confirmed by epicardial mapping studies. Premature activation apparently occurred from a site near the endocardium of the basal region of the left ventricle and surgical interruption could not be planned on the basis of data provided by epicardial mapping.

The role of vectorcardiography in assessing patients with the WPW syndrome is discussed.
Beneficial Effects of Vasodilator Agents in Severe Mitral Regurgitation Due to Dysfunction of Subvalvar Apparatus
Authors: CHATTERJEE KANU , PARMLEY WILLIAM W. , SWAN H. J. C. , BERMAN GILBERT , FORRESTER JAMES , MARCUS HAROLD S.
Published: June 2012

To assess the potential beneficial effects of vasodilator agents in patients with severe mitral regurgitation, sodium nitroprusside was administered intravenously at a rate of 16 to 100 µg/min in eight patients with clinically significant mitral regurgitation presumably due to dysfunction of the subvalvar apparatus. In all patients there was a decrease in the magnitude of the peak `V' wave (from 50 ± 4.5 to 19 ± 2.9 mm Hg) and in left ventricular filling pressure (33 ± 1.8 to 16 ± 1.4 mm Hg), together with a decreased intensity of the apical pansystolic murmur. There was a significant increase in forward cardiac index (2.2 ± 3.5 to 3.3 ± .47 liter/min/M
2
) and forward stroke volume index (23 ± 4.4 to 36 ± 6.6 ml/M
2
) along with a reduction in systemic vascular resistance (1802 ± 331 to 1102 ± 241 dynes/sec/cm
-5
). In the five patients in whom the therapy was continued, relief of symptoms of pulmonary venous congestion occurred. In the four patients in whom left ventricular volumes were determined angiographically, the observed increase in forward stroke volume was due to a reduction in the regurgitant fraction. These findings suggest that the use of vasodilator agents like nitroprusside can achieve the major objectives of treatment of patients with mitral regurgitation: an increase in forward stroke output, a reduction in regurgitant volume and a decrease in pulmonary venous pressure.
His Bundle Electrograms of Dog
Authors: VARGHESE P. JACOB , ELIZARI MARCELLO V. , LAU SUN H. , DAMATO ANTHONY N.
Published: June 2012

Transmembrane potentials from the penetrating and branching portions of the bundle of His were simultaneously recorded along with bipolar extracellular electrograms. Recordings were obtained during periods of normal antegrade and retrograde conduction and also during various degrees of conduction delay and block within and distal to the bundle of His. The onset and termination of extracellular electrogram coincided with the upstrokes of the transmembrane action potentials recorded from the penetrating and branching portions respectively and the duration of the extracellular electrogram equaled the interelectrode conduction time. Thus, the extracellular electrogram accurately reflected the timing and duration of the electrical activity of the entire bundle of His (penetrating and branching portions). Intra-His bundle conduction delay as determined by an increase in interelectrode conduction time and a decrease in the upstroke velocity of phase O of the action potentials, resulted in a decrease in the amplitude and an increase in the duration of the extracellular recording. Significant intra-His bundle conduction delay resulted in two His bundle deflections (H and H') in the extracellular electrogram recordings. The onset of the two His deflections coincided with the upstrokes of the two transmembrane potential recordings. When intra-His bundle block occurred the action potential distal to the block and the corresponding deflection on the extracellular recording disappeared. The results of this study provide further evidence supporting the validity of clinical electrode-catheter recordings of His bundle activity.
The Role of Glucagon Hypersecretion in the Pathogenesis of Hyperglycemia Following Acute Myocardial Infarction
Authors: LANIADO SHLOMO , SEGAL PESACH , ESRIG BARRY
Published: June 2012

In a group of nondiabetic patients, postinfarction hyperglycemia was found to be closely associated with high levels of plasma immunoreactive glucagon (IRG).

It is proposed that, in certain cases, hyperglycemia following acute myocardial infarction may be related to a temporary and uninhibited rise in plasma glucagon levels, probably stimulated by the major stress of acute myocardial infarction.
Doppler Echocardiography
Authors: JOHNSON STEVE L. , BAKER DONALD W. , LUTE ROBERT A. , DODGE HAROLD T.
Published: June 2012

A range-gated pulsed Doppler flowmeter has recently been developed that measures the average velocity of blood flow within a small tear-drop shaped (4 mm by 2 mm) sample volume. Unlike the continuous wave Doppler, the distance from the transducer face to the sampling site can be continuously varied by a range adjustment knob.

Twenty patients with cardiac murmurs were evaluated in a noninvasive laboratory by brief cardiac physical examination, abbreviated phonocardiogram, complete echocardiogram, and localization of the murmurs by Doppler echocardiography. The localization depends on the detection of turbulent flow or jets at the sampling site. The murmurs included the diastolic rumble of mitral stenosis, mitral regurgitation, the murmur of left ventricular outflow tract obstruction, aortic stenosis, aortic insufficiency, diastolic rumble of tricuspid stenosis, augmented right ventricular filling sound in atrial septal defects, pulmonic stenosis, pulmonic insufficiency, and high velocity flow through the obstruction in ccarctation of the aorta.
Diminution and Closure of Large Ventricular Septal Defects After Pulmonary Artery Banding
Authors: MESKO ZOLTAN G. , JONES JIMMY E. , NADAS ALEXANDER S.
Published: June 2012

In a period of 15 years (1957-1972), 114 infants (51 males, 63 females) with the diagnosis of ventricular septal defect and congestive heart failure underwent pulmonary artery banding at The Children's Hospital Medical Center in Boston. A second study performed in 55 of these revealed the left-to-right shunt through the ventricular septal defect to be greatly diminished in seven and completely closed in three.

Pulmonary artery banding proved clinically beneficial to all patients restudied. Important hemodynamic changes, documented at the second study in all ten patients, included a significant decrease in left-to-right shunt and a drop in pulmonary arteriolar resistance to normal range. The right ventricular pressure, post banding, ranged from suprasystemic levels in those with muscular defects to half systemic levels in the majority of those with membranous defect.

The muscular ventricular septal defects closed by muscular tissue, the membranous defects by aneurysm formation at the "exit" of the left-to-right shunt on the right ventricular septal surface.

There is a surprisingly high closure rate (19%) in these large ventricular septal defects after pulmonary artery banding noted. Hemodynamic mechanisms to account for closure are proposed.
Surgical Closure of the Ductus Arteriosus in Premature Infants
Authors: EDMUNDS L. HENRY , GREGORY GEORGE A. , HEYMANN MICHAEL A. , KITTERMAN JOSEPH A. , RUDOLPH ABRAHAM M. , TOOLEY WILLIAM H.
Published: June 2012

During a 62-month period patent ductus arteriosus (PDA) was diagnosed in 88 premature infants with birth weights less than 1750 g. Twenty-one of these infants required operative closure of the PDA. Six infants had uncontrolled heart failure without associated pulmonary disease. Fifteen infants had severe idiopathic respiratory distress syndrome (IRDS) and required operation for deteriorating pulmonary function when heart failure developed. Twelve of these 15 infants weighed less than 1250 g at birth. The ductus arteriosus was ligated in 19 patients and was divided in two patients. The six infants without IRDS survived, and four are completely normal. Of 15 infants with IRDS eight had steady improvement in pulmonary function after operation. Three of these eight patients eventually died. In three infants pulmonary function improved slowly and in two patients pulmonary function did not improve after operation; all of these patients eventually died. Two patients died of peritonitis secondary to bowel ischemia. Of the five infants with IRDS who are alive, one is two months of age, two are moderately retarded in psychomotor development, and two, who developed hydrocephalus, are severely retarded. Although operation successfully controls heart failure in premature infants with PDA and IRDS, progressive pulmonary disease and the complications of extreme prematurity pre-empt good results in most of these infants.
Cineradiographic Evaluation of Prosthetic Cardiac Valves
Authors: WHITE ALAN F. , DINSMORE ROBERT E. , BUCKLEY MORTIMER J.
Published: June 2012

Forty-nine patients whose clinical symptoms suggested a leaking cardiac prosthetic valve were studied by both cineradiography and angiocardiography. We found a wider range of tilting motion of the nonleaking mitral valve than has been previously shown. An angle of tilt greater than 6° for the prosthetic aortic valve strongly suggests separation of the prosthesis from its bed with a paravalvular leak, while the angle of tilt suggestive of a paravalvular leak for a prosthetic mitral valve is 12°. However, a tilt of less than these values does not entirely exclude the existence of a leak. We strongly suggest that routine cineradiography be done in each patient shortly after surgery, as a basis for comparison if the patient later develops a murmur or congestive heart failure.
De Subitaneis Mortibus
Authors: JAMES THOMAS N. , FROGGATT PETER , MARSHALL THOMAS K.
Published: June 2012

The unexpected finding of a right coronary artery embolism in a human fetus of five months gestational age led to an examination of the hearts of 15 other fetuses lost at approximately the same period of pregnancy. No other examples of coronary embolism were found, indicating that this is not a frequent cause of fetal death. Possible mechanisms of death in the index case are discussed on the basis of the anatomic distribution of the coronary arteries, the blood supply to the sinus node and atrioventricular junction, and the configuration of the interatrial septum.
Ventricular Origin of Bidirectional Tachycardia
Authors: KASTOR JOHN A. , GOLDREYER BRUCE N.
Published: June 2012

Electrophysiological, hemodynamic and angiographic studies were performed on an 18 year old woman with asymptomatic recurrent bidirectional tachycardia of eight years' duration and mild hyperkalemic periodic paralysis. Multiple surface electrocardiograms and His bundle and right atrial electrograms revealed that 1) all beats during bidirectional tachycardia originated in the left ventricle; 2) the two forms of ventricular beats in the bidirectional tachycardia had qR patterns in lead V
1
(suggesting left ventricular origin) and axes in the frontal plane of –75° and +110°; 3) the interectopic interval of the two forms of QRS in bidirectional tachycardia was relatively fixed at 440-470 msec; 4) the runs of bidirectional tachycardia always terminated with the beat with right axis deviation; 5) fusion between sinus beats and one of the two forms of ventricular beats produced multiform complexes observed on the electrocardiogram; 6) the sinus beats showed T wave abnormalities and their A-H and H-V intervals were normal. Lidocaine and atrial pacing at an interval of 500 msec each separately suppressed the arrhythmia. Administration of potassium chloride to a blood level 5.4 mEq/liter and of procainamide did not affect the arrhythmia. Hemodynamic, left ventricular and coronary angiographic studies were normal. Bidirectional tachycardia in this case originated in the left ventricle and was unassociated with digitalis intoxication or demonstrable nonelectrical cardiac pathology.
Communication of Mitral Valve with Both Ventricles Associated with Double Outlet Right Ventricle
Authors: TANDON RAJENDRA , MOLLER JAMES H. , EDWARDS JESSE E.
Published: June 2012

A rare case of an infant with "double inlet right ventricle" (straddling mitral valve) and double outlet right ventricle is described. Coarctation of the aorta was associated.

A left-to-right shunt resulted from part of the mitral valve opening into the right ventricle and also from the presence of a ventricular septal defect. The infant's clinical features reflected the shunt, although the valvular abnormality had not been suspected clinically. It is anticipated that left atriography might have identified this rare type of straddling atrioventricular valve.
Noninvasive Technique for Detection of Electrical Activity During the P-R Segment
Authors: BERBARI EDWARD J. , LAZZARA RALPH , SAMET PHILIP , SCHERLAG BENJAMIN J.
Published: June 2012

Many recent clinical studies of the His-Purkinje system have utilized intracardiac catheter recordings. This study describes a technique for recording activity of the ventricular specialized conduction system from the body surface. Unlike the standard electrocardiographic signals, approximately one mV at the body surface, the electrical activity of the His-Purkinje system is in the microvolt range at the body surface.

In 15 anesthetized dogs, His bundle electrograms, standard ECG recordings, and a highly amplified, filtered bipolar lead across the chest were recorded. The application of signal averaging to the surface leads allows for extraction of the periodic signal (His-Purkinje activity) from random electrical noise. The heart was paced from the right atrium to insure periodicity of the heart rate and to obtain a valid average. By pacing at progressively higher rates, there was a progressive increase in the P-R segment, so that a series of potentials (defined here as the C complex) could be observed occurring prior to ventricular activity. The morphology and temporal relationships of His bundle (H) activity and the G complex to ventricular activity remained constant at all paced rates. H-V times averaged 29 ± 2 msec; correspondingly, the onset of G to V was 29 ± 2 msec. Procainamide was used to alter His-Purkinje conduction times. Comparison of the preventricular activity with the His bundle electrogram showed almost identical time intervals in the control and after drug administration, H-V = 37 ± 3 msec. Thus by using the signal averaging technique, signals that are associated with the His-Purkinje system can be detected on the body surface and validated in various experimental situations.
Ankylosing Spondylitis and Aortic Regurgitation
Authors: BULKLEY BERNADINE H. , ROBERTS WILLIAM C.
Published: June 2012

Clinical and cardiovascular necropsy findings are described in eight patients with combined ankylosing spondylitis and aortic regurgitation. All were men (aged 34-55 years), each had peripheral arthritis in addition to spondylitis, all had severe congestive failure, and six had conduction disturbances. In three patients aortic regurgitation was present before distinctive radiologic changes of ankylosing spondylitis were apparent and only two patients had advanced arthritic changes of ankylosing spondylitis. Thus, cardiac dysfunction may be present before signs of spondylitis are apparent, and aortic regurgitation may be severe when signs of spondylitis are minimal. A characteristic cardiovascular morphologic abnormality was present in each patient. The aortic valve cusps and the aorta behind and immediately above the sinuses of Valsalva were thickened, the latter by dense adventitial scar tissue and by intimal fibrous proliferation. In each patient the scar tissue in the root of aorta extended below the base of aortic valve to produce a subaortic fibrous ridge. The subaortic bump involves the base of anterior mitral leaflet and may cause mitral regurgitation. Extension of the fibrous scar into ventricular septum may cause heart block. The distinctive cardiovascular morphologic findings in patients with ankylosing spondylitis clearly separate this condition from syphilis and other entities associated with aortic regurgitation.
The Half-Axial Projection
Authors: BUNNELL IVAN L. , GREENE DAVID G. , TANDON RAVINDER N. , ARANI DJAVAD T.
Published: June 2012

The half-axial view is a dividend of large film selective coronary arteriography. The half-axial projection is obtained by combining caudal tilt of the overhead tube with rotation of the patient into the right posterior oblique position. Thus, the main left coronary artery and the proximal portions of its primary and secondary branches are maximally displayed because the X-ray beam is nearly perpendicular to these vessels and overlap is minimized. The half-axial view adds less than two minutes to the procedure and in nearly half of our patients adds significantly to the arteriographic assessment of the left coronary artery.
The Electrophysiologic Time-Course of Acute Myocardial Ischemia and the Effects of Early Coronary Artery Reperfusion
Authors: COX JIMMY L. , DANIEL THOMAS M. , BOINEAU JOHN P.
Published: June 2012

Bipolar potentials were recorded from intramural electrodes located within areas of acute myocardial ischemia in dogs. Alterations in bipolar potential electromotive force (EMF) and local activation times were measured at predetermined intervals up to 12 hours after coronary occlusion. Histochemical stains were used to correlate structural-biochemical changes with sites of electrophysiologic changes. In severely ischemic areas, bipolar potentials lost 50% of their preocclusion EMF within 30 min and 95% within six hours at which time all parameters stabilized. Lesser decreases in bipolar potential EMF were recorded in the peripheral areas of the infarct. Bipolar potential EMF increased at the junction of ischemic and normal myocardium. Activation time was delayed in ischemic areas but no correlation between the magnitude of delay and the degree of tissue ischemia could be established. Coronary reperfusion after 30 min, one hr, two hr and six hr of occlusion resulted in some return in bipolar potential EMF, decreasing as a function of duration between occlusion and reperfusion.

Variation in the degree of ischemia of different zones of injury within an acute myocardial infarction, as well as a different response of those zones to the return of blood flow, was shown.
Digitalis in the Sick Sinus Syndrome
Authors: ENGEL TOBY R. , SCHAAL STEPHEN F.
Published: June 2012

The effect of digitalis in patients with sinoatrial node dysfunction was studied. Atrial pacing studies were performed while His bundle electrograms were recorded in fourteen patients with sinus bradyeardia, syncope, or related symptoms. Measurements were repeated after 0.01 mg/kg ouabain, followed in some by 1 mg atropine. Ouabain produced a significant shortening of sinoatrial recovery time, but no significant change in heart rate. Atropine normalized sinoatrial recovery times in most patients. This study demonstrates that digitalis causes an increase in automaticity in the sick sinus syndrome as reflected by a shortened sinoatrial recovery time. The efficacy of contemplated therapeutic agents in sick sinus syndrome can be evaluated by rapid atrial pacing. When clinically indicated, digitalis may be used for congestive heart failure or tachyarrhythmias in the sick sinus syndrome in the absence of significant A-V conduction disease.
Echocardiographic Assessment of Left Ventricular Outflow Width in the Selection of Mitral Valve Prosthesis
Authors: NANDA NAVIN C. , GRAMIAK RAYMOND , SHAH PRAVIN M. , DEWEESE JAMES A. , MAHONEY EARLE B.
Published: June 2012

Assessment of left ventricular outflow tract (LVO) width was made from preoperative mitral valve echocardiograms in 26 patients with pure or predominant mitral stenosis who later had valve replacement. LVO width was measured as the minimum space between the ventricular septal echo and the anterior mitral leaflet at beginning systole. Prosthesis encroachment on LVO (PE) was estimated by comparing the length of the poppet expected to protrude into the LVO in systole with LVO width determined by ultrasound (poppet length/LVO width x 100). Group 1 (12 patients) had normal LVO widths (≥20 mm) and received Starr-Edwards prostheses. There was one in-hospital death in this group. Group 2 (seven patients) had narrow LVO (<20 mm) and also received Starr-Edwards prostheses. Five patients died, four of them due to low cardiac output syndrome. Group 3 (seven patients) also had narrow LVO, but Cross-Jones disc prostheses were used. Only one died. The high mortality in Group 2 appears to be related to obstruction of LVO by the caged ball prosthesis; PE in this group ranged from 60% to 80% while it was less than 50% in all but two patients in Group 1. A low profile prosthesis appears desirable when the LVO width measures <20 mm by echocardiography.
Diagnosis of Obstructive Coronary Disease by Maximal Exercise and Atrial Pacing
Authors: KELEMEN MICHAEL H. , GILLILAN RONALD E. , BOUCHARD RICHARD J. , HEPPNER RICHARD L. , WARBASSE J. RICHARD
Published: June 2012

The reliability of graded maximal exercise treadmill testing and right atrial pacing in diagnosing significant obstructive coronary artery disease was evaluated in 74 consecutive patients referred to a cardiac unit with chest pain consistent with angina pectoris. The results of maximal exercise testing and right atrial pacing, with regard to the presence or absence of the patient's characteristic chest pain or discomfort and ischemic ST segment depression, were compared with the findings determined by selective coronary arteriography. Ischemic ST segment depression was defined as a downward displacement of one full mm or more of a horizontal or downward sagging ST segment.

Forty-nine of the 74 patients studied were found to have significant coronary arteriographic obstruction, i.e., greater than 75% obstruction of one major coronary artery. The occurrence of the patient's characteristic chest pain or discomfort during maximal exercise testing or right atrial pacing is an excellent indicator of the presence of obstructive coronary artery disease, since all of the 41 patients developing their characteristic pain on maximal exercise testing had coronary arteriograms positive for obstructive coronary disease (no false positives), and 46 of 47 patients with characteristic chest pain on right atrial pacing had selective coronary arteriograms positive for obstructive coronary disease. When present, one mm ST depression during maximal exercise treadmill testing also reliably indicates arteriographic obstructive coronary disease (26 of 27 patients). However, the presence or absence of ischemic ST depression during right atrial pacing is a particularly unreliable indication of the presence or absence of arteriographic obstructive coronary disease: 15 of 25 false positive tests, and 13 of 49 false negative tests.
Cesium-129 Myocardial Scintigraphy to Detect Myocardial Infarction
Authors: ROMHILT DONALD W. , ADOLPH ROBERT J. , SODD VINCENT J. , LEVENSON NORMAN I. , AUGUST LEON S. , NISHIYAMA HIROSHI , BERKE RAYMOND A.
Published: June 2012

Cesium-129 is concentrated in the myocardium after intravenous administration permitting myocardial imaging. The dosage used was 2-2.5 mCi in dogs and 3-4 mCi in patients. Four or more views with 200,000 counts per view were obtained 30 to 90 minutes after administration. Control images were obtained in 30 dogs. In two dogs anatomic landmarks were obtained using technetium-99m markers. In 24 dogs, either the anterior descending or circumflex coronary artery was ligated. An area of absent uptake of
129
Cs was seen involving the anterior wall and apex or the inferior-posterior wall, respectively. At postmortem this represented a myocardial infarction (MI) averaging 4x5 cm. Smaller MI (2x3 cm) at postmortem were seen as defects of the anterior wall. Evolution of an acute MI was followed in four dogs. The defect appeared at one hour and gradually increased on serial images. Fifty patients were studied. Each of 20 patients without evidence of MI had the normal horseshoe or doughnut appearance of the left ventricle surrounding the interventricular cavity. Each of 15 patients with acute MI and 10 of the 13 patients with an old MI had a defect on the myocardial image. The three patients without defects had infarction of the inferior wall. One of two patients with coronary insufficiency had a defect. These studies show that good quality myocardial images were obtained with
129
Cs and strongly suggest its potential usefulness in quantification of an acute MI.
Myocardial Fibrosis in Constrictive Pericarditis
Authors: LEVINE HAROLD D.
Published: June 2012

It has been suggested that a tentative preoperative decision favoring a pericardial lesion, on the one hand, or a myocardial lesion, on the other, may be made from certain noninvasive procedures, including the electrocardiogram. An attempt was therefore made to detect associated myocardial fibrosis by electrocardiogram in 67 patients with constrictive pericarditis as proven at catheterization (63 patients), surgery (64 patients) or postmortem examination (12 patients). Seven of the 67 had electrocardiograms characteristic of, and 16 compatible with, old myocardial infarct. The electrocardiographic experience was otherwise typical of the literature with non-specific changes in the T waves or RS-T segments and/or low voltage in the remaining 44. All three autopsied patients whose electrocardiograms were interpreted as diagnostic of an old myocardial infarct and both autopsied patients with electrocardiograms compatible with that diagnosis showed myocardial fibrosis. In seven autopsied cases with non-specific T waves or low voltage, the myocardium was normal in three while four showed myocardial fibrosis. It appears that in a few cases right ventricular hypertrophy might have simulated infarct by inducing tall R waves over the right precordium, or R waves which decreased in amplitude as the electrode was passed from the right to the left precordium.

Pathologic evidence related myocardial fibrosis to: (1) direct subepicardial penetration by the inflammatory process or deposit of fat in the subepicardial myocardium; (2) compromise of coronary blood flow, as by (a) direct throttling of coronary arteries by scar tissue or (b) deficient irrigation of subendocardial layers due to rigidity of the pericardium; or (3) a concomitant myocardial and pericardial process (lupus, radiation fibrosis, rheumatoid). Independent pericarditis and coronary disease was surprisingly rare. This limited experience (1) suggests that, though myocardial fibrosis may be predicted in constrictive pericarditis if the electrocardiogram shows characteristic changes of myocardial infarction, non-specific T wave changes or low voltage may likewise be associated with myocardial fibrosis, and (2) emphasizes that the difficulty in determining the site of a constrictive process may be compounded by the co-existence in the same heart of both a pericardial and a myocardial process.
Hypertension in the Papago Indians
Authors: STROTZ CHARLES R. , SHORR GREGORY I.
Published: June 2012

A study of blood pressure in Papago Indians was undertaken utilizing a computerized health information system. Hypertension was present in close to 20% of the study population. The prevalence of hypertension in the Papago tended to peak during young adulthood and showed very little increase in older age groups. The rates of cardiac, cardiovascular and renal complications were analyzed for the hypertensive and nonhypertensive Papago. Hypertension was associated with increased morbidity from target organ damage despite a low rate of arteriosclerosis. This increased morbidity appeared to be independent of the morbidity associated with diabetes which is also common in the Papago Indians.
Acute Effects of Ethanol on Left Ventricular Performance
Authors: HORWITZ LAWRENCE D. , ATKINS JAMES M.
Published: June 2012

The cardiac effects of ethanol were studied in six conscious dogs chronically instrumented for measurement of left ventricular pressure, internal transverse diameter, and outflow. Successive intravenous infusions of ethanol produced blood levels of 120 ± 16 (
sem
) mg% (infusion #1) and 311 ± 19 mg% (infusion #2). Stroke volume decreased from 20.1 ± 1.6 ml preinfusion to 17.2 ± 1.9 ml after infusion #1 (
P
< 0.01) and 13.6 ± 1.9 ml after infusion #2 (
P
< 0.01). Left ventricular end diastolic pressure increased 2.5 mm Hg with infusion #1 (
P
< 0.05) and 6.0 mm Hg with infusion #2 (
P
< 0.05). Left ventricular dp/dt max fell 17% with infusion #1 (
P
< 0.001) and 30% with infusion #2 (
P
< 0.01). Left ventricular diameter increased at end diastole and end systole with ethanol. Heart rate was unchanged with infusion #1 and increased with infusion #2; left ventricular systolic pressure was unaltered. Studies after pharmacological autonomic denervation with propranolol and atropine demonstrated changes in left ventricular dp/dt max, left ventricular end diastolic pressure, and stroke volume similar to unblocked results. Thus ethanol at blood levels commonly encountered in social usage is a potent myocardial depressant.
Left Ventricular Volume Changes After Amyl Nitrite and Nitroglycerin in Man as Measured by Ultrasound
Authors: BURGGRAF GARY W. , PARKER JOHN O.
Published: June 2012

The therapeutic effect of nitrites in myocardial ischemia is considered to be due in part to a reduction of left ventricular volume but measurement of this parameter in man has been difficult. The technique of echocardiography was used to measure changes in left ventricular end-diastolic volume (LVEDV) and end-systolic volume (LVESV) after administration of amyl nitrite (AN) and nitroglycerin (NG) in 20 normal subjects. Control LVEDV was 131 ± 8 ml (mean ±
sem
) and LVESV 30 ± 2 ml. After AN, LVEDV fell 18 ± 2% (
P
< 0.001) and LVESV by 57 ± 3% (
P
< 0.001) in 15 sec to 1 min. Heart rate (HR) rose from 68 ± 3 to 108 ± 4 beats/min at 1 min and blood pressure (BP) fell from 119/69 ± 3/2 to 99/47 ± 4/3 mm Hg. Following NG, LVEDV fell 11 ± 2% (
P
< 0.001) and LVESV 21 ± 3% (
P
< 0.001) within 2-5 min. HR rose from 65 ± 2 to 72 ± 3 beats/min and BP fell from 111/67 ± 3/2 to 102/70 ± 5/2 mm Hg at 3 min. Cardiac output increased from 6.9 ± 0.3 to 11 ± 0.9 L/min 30 sec after AN while no significant change occurred with NG. Stroke volume decreased from 101 ± 6 to 93 ± 5 ml/beat 5 min after NG while no significant change occurred after AN. This study has shown that both AN and NG produce significant decreases in LVEDV and LVESV which may contribute to their beneficial effects in myocardial ischemia.
Analysis and Correction of Pressure Wave Distortion in Fluid-Filled Catheter Systems
Authors: FALSETTI HERMAN L. , MATES ROBERT E. , CARROLL ROBYN J. , GUPTA RAMJI L. , BELL ADAM C.
Published: June 2012

Dynamic characteristics of a variety of catheters and their dependence on various operating parameters are presented. Careful flushing of the catheter with degassed water or saline considerably improves the performance of these systems. The operating temperature, number of catheter uses, and average transmural pressure difference do not have a significant effect.

The error due to catheter distortion in commonly used left ventricular performance indices (end diastolic pressure, peak systolic pressure, maximum dp/dt and V
max
) was assessed. On the basis of these results, it is shown that the natural frequency of the catheter system must be greater than 40 Hz to produce results accurate to 10%.

The experimental data were used to develop a semi-empirical model for the catheter transducer system. This model was used in the design of an analog compensator to further improve the dynamic characteristics of the catheter transducer system. The compensator requires only two parameter settings, catheter natural frequency and damping ratio.
Conditions Simulating the Tetralogy of Fallot
Authors: RAO B. N. SATYANARAYANA , EDWARDS JESSE E.
Published: June 2012

Cyanosis on the basis of a right-to-left shunt at the ventricular level results from pulmonary stenosis associated with a ventricular septal defect. While the tetralogy of Fallot is the most common anatomic state underlying this functional abnormality, there are a variety of anatomic states which may yield the same functional disturbance. These may be divided into three groups depending upon the state of the major arterial vessels. In each of the first two of the three groups, there are two arterial vessels. In one group, the great vessels are in normal relationship to each other, while in the second group the great arteries are transposed. In the third group, one arterial vessel leaves the heart and, from it, branches carry blood to the lungs.
The Effects of Cycle Length on Cardiac Refractory Periods in Man
Authors: DENES PABLO , WU DELON , DHINGRA RAMESH , PIETRAS RAYMOND J. , ROSEN KENNETH M.
Published: June 2012

The effects of pacing-induced changes in cycle length on the refractory periods of the atrium, A-V node and His-Purkinje system were studied in 24 patients using the extra stimulus technique. Refractory period determinations were made at two or more cycle lengths in all patients. Slopes relating cycle length and refractory periods were calculated using the least squares method.

Both the effective and functional refractory periods (ERP and FRP) of the atrium shortened with decreasing cycle lengths, with a mean slope of +0.155 and +0.129 respectively. A-V nodal ERP lengthened (mean slope, –0.177) while A-V nodal FRP shortened slightly (mean slope, +0.126). Bundle branch refractory periods as well as relative refractory periods of the His-Purkinje system also decreased, with mean slopes of +0.270 and +0.360, respectively. The ERP of the A-V node at any cycle length was related to the A-H at that cycle length (
r
= +0.646,
P
< 0.001).

The responses of the human heart to changes in cycle length are generally similar to those previously described in the animal laboratory. Such information contributes to our understanding of electrocardiographic phenomena such as aberrant conduction.
Gas Endarterectomy of Right Coronary Artery
Authors: KLIE JACK H. , JOHNSON LEWIS , SMULYAN HAROLD , POTTS JAMES L. , OBEID ANIS I. , FRUEHAN C. THOMAS , EICH ROBERT H. , PARKER FREDERICK B. , WEBB WATTS R.
Published: June 2012

Results of gas endarterectomy of the right coronary artery were evaluated in 29 consecutive patients. There were one surgical and two early postsurgical deaths. All three had postmortem examination, and in two there was occlusion of the gas endarterectomy. Five patients did not have repeat catheterization. Twenty-one patients were completely re-evaluated and had repeat cardiac catheterization one to sixteen months after surgery (mean eight months). Ten patients (Group A) had gas endarterectomy without a saphenous vein graft to the right coronary artery. Only one patient had significant vessel patency. Eleven patients (Group B) had the combined procedure of a saphenous vein graft anastomosed to the segment of artery that had the endarterectomy. There was excellent graft patency in seven patients (64%) and good distal flow into the segment that had endarterectomy in six of the seven patients. In conclusion, gas endarterectomy is not of value unless it can be combined with a saphenous vein graft to provide good flow to the distal vessel that had endarterectomy. Results with the combined procedure suggest that even with a severely diseased artery, gas endarterectomy can often provide continuing distal runoff for the graft.