bluuebunny/crossref_metadata_2025 huggingface dataset:
Re-entry due to manifest and concealed. His bundle ectopic systoles. Report of a case.
Authors: El-Sherif N , Befeler B , Aranda J , Castellanos A , Lazzara R
Published: June 2012

Concealed (C) His bundle ectopic systoles (H') have been shown in man to give rise to first and second degree atrioventricular (A-V) block and to simulate nonconducted atrial premature beats (P'). This report outlines a hitherto undescribed electrophysiologic consequence of H' in a 69-year-old man with arteriosclerotic heart disease and a Wenckebach type second degree A-V block in the His-Purkinje system. During a His bundle study, H' were shown to conduct either to the atria and ventricles with varying relationships to P' and QRS, or to conduct only to the atria, simulating nonconducted P' or atrial fusion beats. Both types of H' could initiate a re-entrant arrhythmia during retrograde conduction. Of particular interest are late coupled H' that failed to conduct to the ventricles and also failed to activate the atria because of prior capture by the sinus impulse (CH'). These CH' could also initiate re-entry by conducting retrogradely to engage the subatrial re-entry circuit. Evidence is presented to suggest re-entry occurs by way of a retrograde concealed accessory pathway and antegrade conduction in the atrioventricular node.
Aortocoronary bypass grafting in a child with coronary artery obstruction due to mucocutaneous lymphnode syndrome: report of a case.
Authors: Kitamura S , Kawashima Y , Fujita T , Mori T , Oyama C
Published: June 2012

A four-year-old boy with a myocardial infarct and total occlusion of the right coronary and the left anterior descending coronary arteries due to mucocoutaneous lymphnode syndrome (MCLS). confirmed by selective coronary arteriography, underwent successful double aortocoronary bypass grafting. Patency of the grafts was demonstrated by graft angiography and the improvement of the contractile pattern of the left ventricle was reflected by the increase in ejection fraction from 0.45 to 0.61. This is the first patient successfully treated by aortocoronary bypass grafting for coronary artery obstructive lesions due to MCLS. This experience has demonstrated the feasibility of surgical management in a child with coronary artery obstruction due to MCLS. However, there are unanswered questions regarding the fate of the saphenous vein graft in relation to the growth of a child. Long-term clinical and angiographic follow-ups are mandatory to determine the significance of this mode of surgical treatment for the sequela of MCLS.
The effect of premature atrial depolarization on sinus node automaticity in man.
Authors: Breithardt G , Seipel L
Published: June 2012

Sino-atrial conduction time (SACT) may be calculated from the difference between the length of the return cycle and the spontaneous cycle, using programmed premature atrial stimulation during spontaneous sinus rhythm. This approach to sinoatrial conduction assumes that sinus node automaticity is not changed by premature depolarization. In order to validate this assumption, we compared the length of the post-return cycles to the spontaneous cycle length in 71 patients. Patients were grouped according to clinical diagnosis and the value of calculated SACT. At long coupling intervals at which no reset of the sinus node occurred there was only a small prolongation of the post-return cycles (less than 8.4 msec, on an average) compared to the spontaneous cycle length. This suggests no or only an insignificant effect of premature depolarization on the sinus node. However, during test stimuli leading to reset of the sinus node, the post-return cycles were significantly prolonged between 20 to 30 msec, on an average. The response of the individual cases sometimes varied to a great extent. In patients who demonstrated a progressive linear prolongation of the return cycles at decremental shortening of the test interval, there was no significant prolongation of the post-return cycles versus the spontaneous cycle length. We conclude that 1) premature depolarization of the sinus node may have a depressant effect on sinus node automaticity, which, if present, is usually small; 2) calculation of SACT using the extrastimulus technique may overestimate true SACT.
Review of the pocket-electrocardiograph (PECG) in a large general medical clinic.
Authors: Kishida H , Akazome T , Kimura E , Rikli A E
Published: June 2012

Two hundred and twenty patients were selected for testing with the patient-activated Pocket Electrocardiography (PECG) because angina pectoris and similar diagnoses could not be excluded. They were selected during a 30-month period from the population of approximately 12,000 new patients visiting a general medical clinic at Nippon Medical School Hospital. The test confirmed the preliminary diagnosis in 79.1%; 9.6% were not confirmed and 11.3% did not have an attack during the PECG examination. The PECG examination is useful in the differential diagnosis of angina pectoris, cardiac neurosis, phantom arrhythmia, and arrhythmia when the routine ECG examinations are essentially negative.
Esophageal echocardiography.
Authors: Frazin L , Talano J V , Stephanides L , Loeb H S , Kopel L , Gunnar R M
Published: June 2012

Esophageal echocardiography has been developed for use in patients with chronic obstructive pulmonary disease and is a safe diagnostic procedure which provides high resolution mirror image echoes of many cardiac structures. Conventional anterior and esophageal echocardiograms were performed in 38 subjects. Esophageal echoes were of diagnostic quality in all 38 subjects, anterior echoes were of diagnostic quality in only 18. Measurements from anterior and esophageal echocardiograms correlated well for aortic valve diameter (r = 0.87), left atrium diameter (r = 0.96), mitral valve EF slope (r = 0.97) and less well for aortic root diameter (r = 0.69).
Intracardiac repair of cardiac malformations with atrioventricular discordance.
Authors: Fox L S , Kirklin J W , Pacifico A D , Waldo A L , Bargeron L M
Published: June 2012

Twenty-six patients with atrioventricular discordance and a variety of ventriculo-arterial connections have had appropriate intracardiac repairs. Seven of 26 patients (26.9%) died early postoperatively, but only two (11.1%) of 18 patients operated upon since May 1972 have died. Ten patients (40%) developed permanent complete heart block. Two patients died late postoperatively; 16 (84.1% of those surviving the early postoperative period) were in NYHA Class I or II at late follow-up. Seventeen of the patients had "corrected transposition." Six developed tricuspid incompetence with regurgitation into the left atrium after repair. Two patients with atrioventricular discordance and double outlet right ventricle survived operation and are asymptomatic but have permanent pacemakers. One patient died after repair of double outlet left ventricle with atrioventricular discordance. Three of four patients with atrioventricular discordance and "pseudotruncus arteriosus" survived repair with valved external conduits and are well. One of two patients is well after repair of "isolated ventricular inversion" and ventricular septal defect.
Effect of hypertonic mannitol and isoproterenol on regional coronary flow following right ventriculotomy.
Authors: Fixler D E , Watson J T , Wheeler J M , Willerson J T
Published: June 2012

We studied the changes which occurred in regional coronary blood flow after right ventriculotomy and the subsequent effects of hypertonic mannitol or isoproterenol infusion. Regional coronary flows were measured with radioactive microspheres (9 micron) in open-chest anesthetized dogs. Either hypertonic mannitol (25%) was infused at 3.2 ml/min or 7.6 ml/min for 30 minutes, or normal saline at 7.6 ml/min for 30 minutes followed by isoproterenol at 0.05-0.10 mug/kg/min. In the mannitol treated animals right ventricular, left artrial and aortic pressures, heart rate, and cardiac output did not change significantly following vertical ventriculotomy, whereas in the saline-isoproterenol treated animals aortic pressures fell significantly. Coronary flow to the peri-incisional area fell from 41 to 24 ml/min-100 g (P less than 0.05) following ventriculotomy, increased by 34% (P less than 0.05) when osmolality rose after mannitol by 37 mOsm, but was unchanged with isoproterenol. The data indicate that a vertical ventriculotomy reduces flow to adjacent myocardium and that subsequent infusion of hypertonic mannitol at moderate rates significantly increases coronary flow to this region.
Determinants of ventricular septal motion. Influence of relative right and left ventricular size.
Authors: Pearlman A S , Clark C E , Henry W L , Morganroth J , Itscoitz S B , Epstein S E
Published: June 2012

To test the hypothesis that the ventricular septum moves during systole toward the center of the ventricular mass (so that the end-diastolic position of the septum within the heart should determine both the direction and the magnitude of septal motion during systole), echocardiograms from patients with several different hemodynamic burdens were analyzed. A linear relation was noted between the end-diastolic intracardiac position of the ventricular septum and the direction and magnitude of systolic septal motion in 1) forty three patients with an atrial septal defect )regression coefficient r = 0.80), 2) fourteen patients with other causes of right ventricular volume overload (r = 0.82), 3) nineteen patients with left ventricular volume overload (r = 0.74), 4) ten patients with right ventricular pressure overload (r = 0.93), 5) ten patients with left ventricular pressure overload (r = 0.80), 6) twenty-eight normal subjects (r = 0.82). We conclude that, in the presence of normal ventricular activation and contraction, the direction and magnitude of sepatal motion during systole is determined by the intracardiac position of the septum at enddiastole.
Mechanism of abnormal septal motion in patients with right ventricular volume overload: a cross-sectional echocardiographic study.
Authors: Weyman A E , Wann S , Feigenbaum H , Dillon J C
Published: June 2012

To evaluate the mechanism of paradoxical septal motion in patients with right ventricular volume overload (RVVO), short axis cross-sectional, echocardiographic studies of the left ventricle (LV) and interventricular septum (IVS) were performed in 19 patients with paradoxical septal motion due to RVVO and in 20 normal subjects. Short axis study in normal subjects revealed the left ventricle to be a relatively circular structure during both diastole and systole. In patients with RVVO a change in LC diastolic shape was observed. This change in shape varied from a slight flattening of the LV and IVS during diastole to total reversal of the normal direction of septal curvature such that the IVS became concave toward the RV and convex toward the LV. During systole the LV and IVS returned to their normal relatively circular configuration. This change in LV shape from diastole to systole resulted in net motion of the IVS toward the right ventricle (paradoxically). This study therefore suggests that paradoxical septal motion in patients with right ventricular volume overload is a result of a change in the diastolic shape of the left ventricle.
Acute myocardial infarction with normal coronary arteries: a possible manifestation of the billowing mitral leaflet syndrome.
Authors: Chesler E , Matisonn R E , Lakier J B , Pocock W A , Obel I W , Barlow J B
Published: June 2012

The findings in four young patients with the billowing mitral leaflet syndrome who presented with evidence of acute myocardial infarction are reported. Because technically adequate coronary arteriograms demonstrated patent vessels and the electrocardiograms initially showed pronounced elevation of the ST segments as occurs in Prinzmetal's angina, it is postulated that spasm of normal coronary arteries was the operative factor. Scrutiny of those cases of clinically apparent ischemic heart disease with normal coronary angiograms is suggested to establish whether there is in fact a causal relationship with the billowing mitral leaflet syndrome.
Correlation of pathologic Q waves on the standard electrocardiogram and the epicardial electrogram of the human heart.
Authors: Bodenheimer M M , Banka V S , Trout R G , Pasdar H , Helfant R H
Published: June 2012

To evaluate the relationship between abnormal Q waves on the standard ECG and localized ventricular excitation, unipolar epicardial electrograms were recorded over the left ventricle during aortocoronary bypass surgery in 36 patients. Of 20 without standard ECG Q waves, six had abnormal epicardial Q waves, three anterioly and three inferiorly. Of 16 patients with standard ECG Q waves, four had both precordial and anterior epicardial Q waves while seven had Q waves in leads III and aVF and inferior epicardial Q waves. Three of the 14 had Q waves in both precordial and inferior leads of the ECG but epicardial Q waves only from the antero-apical region in two and only from the inferior wall in one. Two patients with Q waves in both III and aVF had no epicardial Q waves. Thus, the standard electocardiogram underestimates epicardial Q waves. If Q waves are present in the standard ECG, they correlate with the presence, although not invariably the location of Q waves on the epicardial electrogram.
Transient transmural reduction of myocardial blood flow demonstrated by thallium-201 scintigraphy, as a cause of variant angina.
Authors: Maseri A , Parodi O , Severi S , Pesola A
Published: June 2012

In previous studies we demonstrated that variant angina could not be attributed to increased myocardial demands. In order to investigate whether a reduction of regional myocardial blood supply could be responsible for these ischemic episodes, we studied regional myocardial perfusion in six patients admitted to our coronary care unit. Myocardial scintigrams, obtained 5-7 min following i.v. injection of 1 mCi of thallium-201, performed during an episode of ST-segment elevation, showed transmural deficits of tracer uptake in the heart wall corresponding to the leads showing ST-segment elevation. These regional deficits ahd disappeared by 2 hours because of late uptake in previously ischemic myocardium. One week later, following injections performed in the absence of acute ischemia, no deficit was apparent. Tracer uptake in ischemic areas was 60% to 85% of that observed a week later. After adjusting for thallium-201 kinetics and counting geometry promblems., these scintigrams actually represent large underestimations of actual flow reduction. Thus variant angina appears to be caused by massive transmural reduction of myocardial blood supply.
Left heart volume characteristics following ventricular septal defect closure in infancy.
Authors: Cordell D , Graham T P , Atwood G F , Boerth R C , Boucek R J , Bender H W
Published: June 2012

Left ventricular and left atrial volume, left ventricular ejection fraction, and left ventricular muscle mass were determined preoperatively and postoperatively in 13 patients who underwent surgical closure of ventricular septal defects in the first two years of life. Left ventricular end-diastolic volume and systolic output averaged 255 +/- 19% (+/- SEM) and 240 +/- 19% of normal, respectively, before operation but fell to within normal limits postoperatively. Left ventricular ejection fraction was normal preoperatively (100 +/- 4% of normal) and remained so after correction (106 +/- 3%, NS). Left ventricular mass was mildly elevated at the preoperative catheterization (271 +/- 21%) and decreased significantly following repair (P less than 0.001). However, the postoperative left atrial volume (147 +/- 14%) remained abnormal (P greater than 0.05). These data suggest that when early surgical closure of a ventricular septal defect is necessary because of failure of medical management, good results with regard to postoperative left ventricular size and function can be expected.
Mechanism of reciprocating tachycardia initiated during sinus rhythm in concealed Wolff-Parkinson-White syndrome: report of a case.
Authors: Sung R J , Castellanos A , Gelband H , Myerburg R J
Published: June 2012

Reciprocating tachycardia in a patient with a leftsided atrioventricular accessory pathway (AP) (Kent bundle, type A) capable only of ventriculo-atrial (V-A) transmission is described. The V-A AP is established as an essential link of the tachycardia circuit, as evidenced by : 1) retrograde atrial activation of the left atrium (LA) 60 msec or more before the low and high right atrium during reciprocating tachycardia and during V-A conduction; 2) the absence of refractory-dependent delay in V-A conduction time with progressively premature ventricular stimulation, characteristic of retrograde conduction through an AP; and 3) the absence of antegrade conduction through the Kent bundle during sinus rhythm, reciprocating tachycardia, pacing from either atrium, or during induced atrial flutter-fibrillation. The onset of the tachycardia was unique in that it could be initiated and perpetuated during sinus rhythm, without a triggering mechanism of an atrial or ventricular extrasystole. The interplay of the following two events seemed to favor the initiation of the tachycardia: 1) shortening of the atrial cycle length causing a decrease in the refractory period of the LA and/or the AP; and 2) the development of rate-dependent left bundle branch block, delaying impulse arrival at the ventricular end of the AP. These observations described an additional mechansim of reciprocating tachycardia in patients with the Wolff-Parkinson-White syndrome.
Platelet aggregation in partially obstructed vessels and its elimination with aspirin.
Authors: Folts J D , Crowell E B , Rowe G G
Published: June 2012

In 35 open chest anesthetized dogs coronary and aortic blood flow were measured with electromagnetic flowmeters while aortic and distal coronary blood pressure and an epicardial ECG were recorded. A fixed amount of stenosis (60-80%) was produced in the coronary artery by an externally applied plastic cylinder. In 24 of the 35 dogs the coronary blood flow showed cyclical reductions to near zero, with a sudden spontaneous return to near control levels. During reduced flow the epicardial ECG showed ST-segment depression suggestive of ischemia, and ventricular premature beats were often noted. Six animals died acutely during episodes of reduced flow. After 35 mg/kg of aspirin were given intravenously the cyclical reductions in coronary blood flow were abolished and the in vitro platelet aggregations were reduced from a control of 62.1 +/- 15 units (Born technique) to an average of 23.7 +/- 12 units. Histologic sections of the narrowed coronary artery obtained when coronary flow was reduced show an amorphous mass in the lumen which was thought to be a platelet aggregate. Perhaps a similar process of platelet aggregation occurs in the stenosed coronary arteries in man, producing acute coronary obstruction, ischemia, and sudden death.
The coronary arteries and left ventricle in clinically isolated angina pectoris: a necropsy analysis.
Authors: Roberts W C
Published: June 2012

Certain clinical and morphologic observations are described in 27 patients with severe isolated angina pectoris of either the stable (five patients) or the unstable form (22 patients). Twenty-four patients died during or shortly after cardiac operations designed to relieve angina pectoris and three died during cardiac catheterization. During life none had had clinical evidence of acute myocardial infarction or congestive cardiac failure. At necropsy, each had diffuse, extensive coronary atherosclerosis with severe luminal narrowing: the lumens of at least two, an average of three, of the four major epicardial coronary arteries were narrowed greater than 75% in cross-sectional area by old atherosclerotic plaques. Despite the severe coronary narrowing, there was little myocardial damage. Left ventricular scarring (excluding papillary muscle) was observed grossly in only 14 (52%) of the 27 patients and in each it involved only a small portion of myocardial wall. The left ventricular cavity was of normal size in all except two patients. The hearts were of normal weight in 15 (56%) patients, and the average increase above the upper range of normal for the other 12 hearts was 19%. Thus, clinically isolated, severe angina pectoris is associated with severe, diffuse luminal narrowing but relatively little myocardial damage.
Right ventricular volume characteristics before and after palliative and reparative operation in tetralogy of Fallot.
Authors: Graham T P , Cordell D , Atwood G F , Boucek R J , Boerth R C , Bender H W , Nelson J H , Vaughn W K
Published: June 2012

Right heart volume data were obtained in 63 patients with tetralogy of Fallot. The patients were divided into three groups: 1) preoperative tetralogy (N=34); 2) post shunt procedure (N=14); 3A) post repair without outflow patch (N=10); 3B) post repair with an outflow patch (N=8). In Group 1 right ventricular end-diastolic volume (RVEDV), RV ejection fraction (EF), and RV systolic output (SO) were all mildly depressed. In post shunt patients, RVEDV was normal but RVEF remained depressed. RVEDV and RVSO increased following a shunt procedure, and these variables were larger in patients with a large versus a small shunt. In Group 3A RVEDV, RVEF, and RVSO were normal. In contrast in patients in Group 3B, RVEDV was increased averaging 177 +/- 15% of normal RVEF was depressed averaging 0.45 +/- 0.04, and RVSO was normal. RV size and pump function are abnormal in patients whose operation requires an outflow tract patch and the factors which may contribute to these abnormalities include a higher RV peak pressure, pulmonary incompetence, and a larger noncontractile outflow tract. Longitudinal studies relating these variables to clinical performance and exercise testing will be important in assessment of the importance of these abnormalities.
Paroxysmal supraventricular tachycardia: is the atrium a necessary link?
Authors: Josephson M E , Kastor J A
Published: June 2012

Whether or not the atrium plays an essential role in initiating and/or sustaining atrioventricular (A-V) nodal re-entrant tachycardia was evaluated in eight patients. In all eight patients, the atrium could be rendered refractory to retrograde atrial echoes during the tachycardia without interrupting the arrhythmia. This was accomplished by introducing atrial premature depolarizations prior to the time the atrium would normally be retrogradely depolarized by atrial echoes. In one patient, two atrial premature depolarizations could be introduced, producing A-V dissociation, without terminating the tachycardia. In another patient, the tachycardia could be initiated without an atrial echo. Our data suggest that most, if not all of the atrium is unnecessary for the initiation and maintenance of A-V nodal re-entrant supraventricular tachycardia.
Analysis of secondary pauses following termination of rapid atrial pacing in man.
Authors: Benditt D G , Strauss H C , Scheinman M M , Behar V S , Wallace A G
Published: June 2012

The first ten cycles following cessation of atrial pacing were evaluated in 44 control subjects (mean age 52.9 +/- 14.88 yr) and 39 patients (mean age 62.9 +/- 15.41 yr) suspected of having sinus node dysfunction (SND). The maximal cycle length for each postpacing cycle following several pacing periods in each control subject was determined, and was normalized by dividing it by the subject's mean spontaneous control cycle length (SCL). Using the control group, a normalized maximal post-pacing response pattern (mean and SD) was derived. For each SND patient, a composite SD for each post-pacing cycle was calculated by adding the patient's SCL variance to the variance determined for each post-pacing cycle in the control group. Two composite SD above the mean value for each post-pacing cycle was selected as the upper limit of the normal recovery response and used to identify abnormal post-pacing responses in the 39 SND patients. Abnormally prolonged cycle lengths subsequent to the first escape cycle (secondary pauses) were found in 16/39 (41.0%) patients, of whom 11/39 (28.2%) had a prolonged SNRTmax. Of importance, 11/12 (91;7%) patients with documented SA block or sinus pauses prior to electrophysiologic study, demonstrated secondary pauses, while only 7/12 (58.3%) had a prolonged SNRTmax. Criteria are derived for the identification of secondary pauses during the postpacing period, and a close association between secondary pauses and the presence of spontaneous SA block or sinus pauses prior to electrophysiologic study is demonstrated.
Hemodynamic effects of vasodilator agents in dogs with experimental ventricular septal defects.
Authors: Synhorst D P , Lauer R M , Doty D B , Brody M J
Published: June 2012

The ratio of pulmonary to systemic vascular resistance (Rp/Rs) largely determines the amount of left-to-right shunting and pulmonary to systemic flow rat (Qp/Qs) in the presence of a large isolated ventricular septal defect. The possibility that pharmacologic reduction of systemic vascular resistance with alpha-adrenergic receptor blockade or beta-adrenergic receptor stimulation would increase the ratio Rp/Rs, and therefore reduce the ratio Qp/Qs, was studied in dogs in which ventricular septal defects had been surgically created. Administration of phentolamine and phenoxybenzamine caused a 42% reduction in Rs and no reduction in Rp. Qs was unchanged and Qp declined by 24% and the ratio Qp/Qs fell by 32%. Infusion of the beta-adrenergic receptor stimulant isoproterenol also reduced Qp/Qs. However, this was accomplished as a result of an increase in Qs and at the expense of an increase in heart rate. As a decline in the ratio Qp/Qs has been shown to be beneficial to patients with large left-to-right shunts, pharmacologic reduction of systemic vascular resistance may prove to be helpful in treating congestive heart failure in those patients with large left-to-right shunts at the ventricular level who are refractory to the usual decongestive measures.
Echocardiographic assessment of the level of cardiac compensation in valvular heart disease.
Authors: Rosenblatt A , Clark R , Burgess J , Cohn K
Published: June 2012

The level of cardiac compensation in valvular disease was studied by relating echocardiographic and cardiac catheterization measurements. Three groups -- compensated, intermediately compensated, and decompensated -- were defined according to the left ventricular angiographic pattern and cardiac output. The echocardiographic ejection indices, percent left ventricular minor diameter shortening, ejection fraction, and fiber shortening rate were significantly higher than normal in compensated mitral regurgitation, lower then normal in compensated aortic stenosis, and within normal limits in compensated aortic insufficiency. In the decomposed state these indices were depressed. Intermediate compensation was best recognized by combining several echocardiographic variables into an echocardiographic score based on multivariate discriminant function analysis. Thus, the compensated volume overload states (aortic and mitral regurgitation) and pressure overload state (aortic stenosis) have separate sets of "normal" echocardiographic values; low ejection indices characterize the decompensated group, while recognition of intermediate compensation requires analysis of multiple echocardiographic variables.
Intracardiac electrography in endocardial cushion defects.
Authors: Jacobsen J R , Gillette P C , Corbett B N , Rabinovitch M , McNamara D G
Published: June 2012

Conduction of the sino-atrial impulse from the high right atrium to the ventricles was studied by intracardiac electrography in 21 unoperated patients, age 3 months to 11 years, with endocardial cushion defects (ECD). The high right atrium-to-low right atrium conduction time was prolonged in 15 of 18 subjects (mean 57 +/- 20 msec). The low right atrium-to-His bundle conduction time (LRA-H) was normal in 16 of 17 subjects (mean 82 +/- 30 msec), prolonged in one. The His-to-ventricle conduction time (H-V) was normal in 16 of 17 subjects (mean 37 +/- 8 msec), equivocally short in one. Nine patients with ECD, age 3 to 21 years, were studied postoperatively. One had an acquired complete atrioventricular block in the His bundle. Two had prolonged LRA-H and two prolonged LRA-H and two prolonged H-V. The surface ECG failed to identify accurately either prolonged atrioventricular conduction or the site of prolongation.
Continuous murmur following Mustard operation for transposition of the great arteries. A sign of pulmonary venous obstruction.
Authors: Park S C , Weiss F H , Siewers R D , Neches W H , Zuberbuhler J R , Lenox C C
Published: June 2012

Three patients developed severe pulmonary venous obstruction following Mustard operation for transposition of the great arteries. Each patient had a soft continuous murmur with distinct diastolic accentuation at the low left sternal border or xiphoid area. Simultaneous recording of intracardiac sound and pressure in one patient showed that the murmur originated at the site of obstruction in the surgically-constructed pulmonary venous atrium. Selective cineangiograms demonstrated the baffle to be the cause of the obstruction. A continuous murmur in a patient following Mustard operation may suggest significant pulmonary venous obstruction.
Left anterior and left posterior hemiblock in tricuspid atresia and transposition of the great vessels: observations and electrocardiographic nomenclature and electrophysiologic mechanisms.
Authors: Schatz J , Krongrad E , Malm J R
Published: June 2012

A patient with tricuspid atresia and characteristic electrocardiographic features of counterclockwise and superiorly oriented frontal plane QRS loop (left anterior hemiblock) is presented. Operative intervention resulted in a clockwise and inferior rotation of the frontal QRS loop (left posterior hemiblock) without the development of complete left bundle branch block. This observation suggests that the electrocardiographic pattern of left anterior hemiblock may result from other mechanisms in addition to block of the left bundle branch fibers oriented toward the anterior part of the left ventricle. The case further suggests that electrocardiographic patterns of apparent A-V conduction defects may not be at all associated with true block in the A-V conduction system. Further, it emphasizes the fact that various electrophysiologic mechanisms may account for identical electrocardiographic patterns.
Oral hydralazine therapy for chronic refractory heart failure.
Authors: Chatterjee K , Parmley W W , Massie B , Greenberg B , Werner J , Klausner S , Norman A
Published: June 2012

The hemodynamic effects of oral hydralazine were investigated in ten patients (nine in NYHA Class IV and one in Class III) with chronic refractory heart failure. With hemodynamic monitoring, adequate oral doses of hydralazine (50 or 75 mg) were determined and then administered every six hours. Hemodynamics were determined at 2-3, 6-8 and 24 hours on hydralazine therapy. Arterial pressure decreased slightly (5%) and systemic vascular resistance decreased significantly (42%). Cardiac and stroke volume index increased by 70 and 66%, respectively, without any significant change in heart rate, pulmonary capillary wedge or right atrial pressure. Hemodynamic improvement was associated with clinical improvement without a major complication. During the follow-up period of 3-7 months, seven of nine patients were in NYHA Class II and one in Class III. One other patient died suddenly six weeks after discharge. These findings suggest that hydralazine in an effective oral vasodilator for the treatment of refractory heart failure.
Subendocardial blood flow in children with congenital aortic stenosis.
Authors: Krovetz L J , Kurlinski J P
Published: June 2012

Subendocardial blood flow may be estimated from the ratio of flow to the subendocardium to myocardial oxygen consumption. The first may be estimated from the diastolic pressure time index (area between aortic and left ventricular (LV) pressure during diastole) and the latter by the tension time index (integral of LV pressure during systolic ejection). Subendocardial flow index (SEFI) averaged 1.27 (0.96-1.78) in 13 children with normal aortic valves. SEFI averaged 0.88 (0.43-1.65) in asymptomatic children with congenital aortic stenosis and was never greater than 0.9 in symptomatic children. Aortic valve area and systolic pressure difference did not correlate well with symptoms. SEFI and aortic valve area increased in 26 of 28 patients after surgery. However, 23 of 28 had varying degrees of aortic regurgitation following valvotomy. Since calculation of SEFI is not affected by aortic regurgitation, it would appear to be a more useful measure of surgical success than aortic valve area.
The relationship of education to blood pressure: findings on 40,000 employed Chicagoans.
Authors: Dyer A R , Stamler J , Shekelle R B , Schoenberger J
Published: June 2012

The relationship of education to both actual blood pressure and the prevalence of high blood pressure, based on a systolic pressure of 160 mm Hg or greater or a diastolic pressure of 95 mm Hg or greater, was analyzed among 27,033 men and women, white and black, age 25-44 and 45-64, from the Chicago Heart Association Detection Project in Industry. The educational status of each individual was categorized as not a high school graduate, high school graduate, some college, or college graduate. A statistically significant inverse association between education and high blood pressure was present in all groups of whites. This association could not be "accounted for" by differences in age, relative weight, and heart rate among the educational strata. Controlling for these variables did, however, lessen the association. Among black males a significant inverse association between education level and blood pressure was found for the younger group. For the older black males there was a clear inverse association although with the small numbers it did not achieve statistical significance. For black females there was no clear association.
Cross-sectional echocardiographic examination of the interatrial septum.
Authors: Dillon J C , Weyman A E , Feigenbaum H , Eggleton R C , Johnston K
Published: June 2012

The interatrial septum has not been readily appreciated by M-mode echocardiography. Cross-sectional echocardiography has the capability of recording the shape and location of the interatrial septum. Real-time cross-sectional echograms using a mechanically oscillating transducer were obtained on 100 consecutive patients. Echocardiographic examination of the left atrium and aorta was obtained in a plane perpendicular to the long axis of the atria. In 15 normal patients and 17 patients with atrial septal defects (ASD) and 51 patients with other forms of heart disease, the interatrial septum was recorded as a linear echo from the aorta to the posterior wall of the left atrium. In six patients who had ostium primum ASDs, the echoes from the interatrial septum disappeared near its expected junction with the interventricular septum. Drop out of echoes in the mid portion of the septum was noted in those patients who had ostium secundum atrial septal defects but this could not be differentiated from normal. These preliminary data indicate that examination of the interatrial septum is feasible and may be specific in those few patients examined so far with ostium primum atrial septal defect. The ability to locate and record the shape of the interatrial septum could have many investigate and clinical uses.
Increases in plasma oncotic pressure during acute cardiogenic pulmonary edema.
Authors: Figueras J , Weil M H
Published: June 2012

Colloid osmotic pressure (COP) was measured in 95 patients with clinical and radiological evidence of acute cardiogenic pulmonary edema. Fifty patients who were admitted for coronary observation but in whom acute myocardial infarctin was excluded, and 21 patients who had sustained acute myocardial infarction without evidence of left ventricular failure served as controls. Significantly higher values of COP, total plasma protein, and hematocrit were observed in patients with pulmonary edema. Increases in COP during pulmonary edema were best explained by transudation of hypooncotic fluid into extravascular spaces. Following treatment of pulmonary edema in 76 patients with furosemide, morphine, and oxygen, pulmonary edema was reversed in 65 patients. Reabsorption of hypooncotic fluid from extravascular sites with a significant decline in COP, total protein and hematocrit followed reversal of pulmonary edema. No significant changes in these parameters were observed in patients who failed to respond to therapy. These observations implicate filtration of hypooncotic fluid from the intravascular compartment during onset of cardiogenic pulmonary edema and reabsorption of hypooncotic fluid into the intravascular compartment during reversal of pulmonary edema.
Hypereosinophilic syndrome with biventricular involvement.
Authors: Hall S W , Theologides A , From A H , Gobel F L , Fortuny I E , Lawrence C J , Edwards J E
Published: June 2012

In a 45-year-old man with hypereosinophilic syndrome, cardiac disease, mainly endocardial thickening and extensive mural thrombosis of both ventricles, was confirmed at autopsy. Early in the course of the disease, right ventricular endocardial biopsy had demonstrated the basic process. Restriction in filling and contraction of the right ventricle were demonstrated by functional studies. By echocardiographic study, progressive reduction in size of the right ventricular cavity and premature opening of the pulmonary valve were demonstrated, while this method was less adequate in identifying the process in the left ventricle.
The specificity of the diffuse pattern of cardiac uptake in myocardial infarction imaging with technetium-99m stannous pyrophosphate.
Authors: Prasquier R , Taradash M R , Botvinick E H , Shames D M , Parmley W W
Published: June 2012

To analyze the specificity of the diffuse pattern of cardiac uptake with technetium-99m stannous pyrophosphate (TcPYP), we evaluated the bone scans of 1,383 noncardiac patients and the myocardial scintigrams of 120 cardiac patients. Seventy (14.4%) of 483 bone scans performed on a scintillation camera revealed diffuse TcPYP cardiac uptake. Among the total 603 camera bone scans and myocardial scintigrams, the incidence of diffuse cardiac uptake was 16% among patients with clinical coronary disease but 13% among those patients without clinical symptoms. Discrete myocardial uptake was seen in 25 of 26 patients with transmural infarction. Femoral vasculature was more frequently visualized (84% vs 3%, P less than 0.001) and left mastectomy occurred more often (30% vs 1%, P less than 0.001) among patients with diffuse cardiac uptake than among patients with negative images, indicating possible blood pool imaging. The diffuse pattern of cardiac uptake appeared nonspecific and may be due to unintentional cardiac blood pool imaging.
Quantification of infarction in cross sections of canine myocardium in vivo with positron emission transaxial tomography and 11C-palmitate.
Authors: Weiss E S , Ahmed S A , Welch M J , Williamson J R , Ter-Pogossian M M , Sobel B E
Published: June 2012

To assess myocardial infarction quantitatively in 15 mm thick transverse sections of the canine heart in vivo we utilized a new technique, positron emission transaxial tomography (PETT) and cyclotron-produced 11C-palmitate (11C-P) injected intravenously. Results were compared to regional myocardial creatine phosphokinase (CPK) depletion, diminished 14C-palmitate accumulation in tissue extracts, and infarction estimated morphometrically 48 hours after coronary occlusion. CPK activity and 14C-P content declined in parallel in transmural biopsies (N=44) from normal and ischemic zones (r=.92) in six dogs; and infarct in 10 mm thick cross sections of the entire left ventricle estimated morphometrically (N=26) in six other animals correlated with CPK depletion in contiguous 2.5 mm thick slices (r=.92). When the percentage of infarction in 15 mm thick cross sections was assessed tomographically in six other dogs 48 hours after coronary occlusion with 11C-P injected intravenously, results correlated with infarction in corresponding cross sections from the same hearts estimated morphometrically (r=.97, N=9) and by analysis of CPK depletion (r=.93, N=9). Thus, PETT permits estimation of infarction in cross sections of the left ventricle in vivo after intravenous injection of 11C-palmitate.
Localization of radiolabeled cardiac myosin-specific antibody in myocardial infarcts. Comparison with technetium-99m stannous pyrophosphate.
Authors: Beller G A , Khaw B A , Haber E , Smith T W
Published: June 2012

The myocardial uptake of radioiodinated (Fab')2 fragments of antimyosin antibody [125I-(Fab')2] was compared with simultaneously administered 99mTc-pyrophosphate (Tc-PYP) in dogs undergoing coronary occlusion for 24 (N=6) or 72 hours (N=5). Relative concentrations of both agents in normal and infarcted myocardium were related to regional blood flow as determined by distribution of 55Sr-labeled microspheres in the same animals. There was an inverse exponential relationship between 125I-(Fab')2 localization and regional blood flow in 24 hr (r=-0.64) and 72 hr (r=-0.80) occluded animals. The greatest uptake of 125I-(Fab')2 was observed in subendocardial layers of the center of the infarct where regional flow was most severely impaired (1-10% of normal flow). Maximal localization of Tc-PYP was observed in subepicardial layers in samples from the periphery of the infarct where flow was only moderately reduced (31-50% of normal). Differences in distribution of these two agents in ischemic myocardium are probably related to differences in kinetics of exit from the blood pool.
Detection of edema associated with myocardial ischemia by computerized tomography in isolated, arrested canine hearts.
Authors: Powell W J , wittenberg J , Maturi R A , Dinsmore R E , Miller S W
Published: June 2012

This study was undertaken to determine if computerized tomography (CT scanning) with an EMI cranial scanner could detect edema associated with myocardial ischemia in canine hearts. A localized area of decreased density in the posterior papillary muscle and surrounding myocardium was detected on serial 8 mm CT scan slices of each heart after 60 min of circumflex artery occlusion and 45 min of reflow of blood. The wet/dry weight ratios and previous electron microscope studies of the ischemic posterior papillary muscles revealed edema accumulation. After 1 hour of arterial occlusion and 12 hours of reflow (which produces extensive necrosis and a decrease in the wet/dry ratio) lesions were still discernible but were less consistently as severe. Permanent ligation of the left anterior descending coronary artery and major collateral arteries for 6 hours also resulted in a lesion of decreased density in the distribution of the occluded arteries. Thus, CT scanning can detect, and is a potential means for sequential noninvasive quantitation of myocardial edema associated with ischemia.
Tachycardia and bradycardia-dependent bundle branch block alternans: clinical observations.
Authors: Cohen H C , D'Cruz I , Arbel E R , Langendorf R , Pick A
Published: June 2012

Eleven patients with tachycardia-dependent, bradycardia-dependent, or "pseudobradycardia-dependent" bundle branch block (BBB) alternans were studied. This classification is based on the following criteria: 1) When alternans is initiated by a sudden acceleration in ventricular rate, or it appears with aberration of the second beat after a pause, the alternans is tachycardia-dependent and results from a 2:1 bidirectional block in the affected bundle branch. 2) When alternans begins with the aberrant complex terminating a pause it is bradycardia-dependent; such an alternans results from alternating bundle branch cycle lengths and refractoriness, possibly produced by alternating transseptal retrograde penetration of the affected bundle branch. 3) In cases referred to as "pseudobradycardia-dependent BBB" alternans, a change from alternans to persiscardia-dependent BBB" alternans, a change from alternans to persistent BBB occurs as the cycle lengthens; however, the disappearance of BBB with further increase of the cycle length proves the tachycardia-dependence of the conduction defect.
Atrial tachycardia without P waves masquerading as an A-V junctional tachycardia.
Authors: Zipes D P , Gaum W E , Genetos B C , Glassman R D , Noble J , Fisch C
Published: June 2012

Two patients who presented by scalar ECG with an A-V junctional tachycardia were demonstrated during an electrophysiologic evaluation to have an atrial tachycardia without P waves in the surface ECG. Case 1 had an atrial tachycardia that conducted through the A-V node with a Wenckebach block. Atrial activity was recorded only from the proximal portion of the coronary sinus and from right atrial areas near the tricuspid valve. Case 2 had an atrial tachycardia that abruptly began and terminated following carotid sinus massage. Atrial activity was recorded only in the coronary sinusos, and pacing at that site resulted in atrial capture, with Wenckebach conduction to the ventricles. These observations demonstrate that an atrial tachycardia without P waves can simulate A-V junctional tachycardia with or without Weckebach block. Such findings may have a bearing on some important electrophysiologic concepts such as the origin of A-V junctional rhythms and the need for atrial participation in A-V nodal re-entry.