bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative assessment of transient left ventricular asynergy in coronary artery disease
Authors: Laucevi A. , Beruk E. , Kosinskas E. , JablonskienE D. , Iva L.
Published: February 2009

The purpose of this study was to determine the diagnostic value of quantitative two‐dimensional echocardiography during transesophageal atrial pacing in assessing the presence and severity of coronary artery disease. Apical four‐ and two‐chamber views were registered at rest and at different pacing rates. Computerized quantitative evaluation of left ventricle wall motion was performed. On the basis of left ventricle wall motion analysis data of 22 individuals with no coronary pathology, as assessed by angiography and with negative exercise ECG and transesophageal atrial pacing ECG test, nomograms for assessment of wall motion abnormalities and for calculation of asynergy area as a measure of wall motion abnormality extent were obtained. The method revealed new transient wall motion abnormalities during pacing or exacerbation of old ones present at rest in 83 of the 89 patients with angiographically proven coronary artery stenosis ⩾70% and in 3 of the 32 controls with no changes in their coronary angiograms. Thus, it showed high sensitivity (93%), specificity (91%), predictive value of positive result (96%), predictive value of negative result (83%), and efficiency of the test (93%). These values appeared to be higher than those calculated for transesophageal atrial pacing ECG, recorded simultaneously with echocardiographic images (81, 87, 95, 62, and 83%, respectively) and for exercise ECG test which was performed in 66 coronary patients and in 29 controls (68, 86, 92, 54, and 74%, respectively). The extent of pacing‐induced left ventricular regional wall motion abnormalities appeared to be directly correlated to the extent of coronary artery disease. Thus, transesophageal atrial pacing two‐dimensional echo stress testing seems to be a valuable method for the evaluation of coronary artery disease and for the assessment of its extent.
Left ventricular muscle mass and diastolic function in patients with essential hypertension under long‐term clonidine monotherapy
Authors: Hüting Jürgen , Mitrovic Veselin , Thormann Jochen , Bahavar Hassan , Schlepper Martin
Published: February 2009

To determine whether alterations of left ventricular (LV) structure are associated with improved LV function under chronic clonidine monotherapy (300–450 g/day) of essential hypertension, 11 male patients (age range 47–61 years) were followed for 5.4 ± 0.9 months using echocardiography and Doppler echocardiography. Blood pressure decreased from a mean of 168/105 to 150/96 mmHg (p<0.01), heart rate remained unchanged (73 ± 10 vs. 71 ± 10 beats/min). LV muscle mass decreased from 350 ± 73 to 297 ± 56 g (p<0.02), LV volume/muscle mass ratio increased from 0.58 ± 0.13 to 0.69 ± 0.12 ml/g (p<0.005). Ejection time increased from 276 ± 17 to 296 ± 17 ms (p<0.01), whereas no significant change was found for pre‐ejection period, ejection fraction, cardiac index and LV dimensions. Doppler analysis revealed improved isovolumic relaxation time (116 ± 17 vs. 84 ± 28 ms; p<0.05), but no change in isovolumic contraction duration, maximal inflow velocities, time‐velocity integrals and their duration, rate of acceleration and deceleration of early and atrial filling, and of their ratios. It is concluded that no reliable improvement in diastolic or systolic LV function is observed in chronic clonidine monotherapy of essential hypertension despite a normalization of blood pressure and a regression of LV hypertrophy.
Prediction of degree of residual stenosis in coronary thrombolysis
Authors: Fujoo Banyo , Matsuda Yasuo , Hamada Yoshio , Takashiba Kiyoshi , Ohno Hiroshi , Ebihara Hironori , Hyakuna Eiji , Iwamoto Susumu
Published: February 2009

In order to predict the residual stenosis in coronary thrombolysis, the factors easily obtained from clinical history—age, gender, history of angina before acute myocardial infarction (AMI), family history, hypertension, diabetes, hypercholesterolemia, smoking, and interval between onset of AMI and recanalization—were observed in 114 patients with successful coronary thrombolysis. In 55 patients with angina before AMI, 29 patients had residual stenosis ≥75% and 26 patients had residual stenosis <75%. In 59 patients without angina before AMI, 15 patients had residual stenosis ≥75%, and 44 patients had residual stenosis <75 %. The presence or absence of angina before AMI was the main variable that discriminated the groups of residual stenosis of more or less than 75 %, which was the only significant independent variable to predict the residual stenosis. These data suggest that the presence of angina pectoris before AMI is likely to be associated with a significant degree of residual stenosis after thrombolysis.
Echocardiographic left ventricular wall thickness: A poor predictor of the severity of aortic valve stenosis
Authors: Griffith Michael J. , Carey Catherine M. , Christopher Byrne J. , John Coltart D. , Stephen Jenkins B. , Webb‐Peploe Michael M.
Published: February 2009

Echocardiographic left ventricular hypertrophy is thought to be helpful in grading the severity of aortic stenosis. This study compared M‐mode echocardiographic left ventricular wall dimensions with Gorlin aortic valve area. Good quality echocardiograms were obtained in 294 patients with aortic stenosis who also underwent cardiac catheterization. Patients with grade 3 or 4 aortic regurgitation were excluded. The correlation was calculated between the aortic valve area and the left ventricular wall dimensions. Correlation coefficients were poor; r=0.13 for the septum, r=0.15 for the posterior wall, and r=0.17 for the mean wall dimension. Correlation was not improved significantly if patients with poor left ventricular function or systemic hypertension were excluded. Correlation with other hemodynamic parameters was better, peak left ventricular systolic pressure having r values of 0.36 and 0.30 for posterior wall and septum. Mean and peak aortic valve gradient had r values approaching 0.30 for both dimensions. If the peak gradient was included in multivariate analysis, the wall dimensions then had no predictive power for severity of aortic stenosis. This study demonstrates that the degree of left ventricular wall hypertrophy is not related to the severity of aortic outflow obstruction and therefore cannot be used to grade the severity of aortic stenosis.
Percutaneous balloon mitral valvuloplasty in rheumatic mitral stenosis: An experience of 50 patients in india
Authors: Shrivastava S. , Dev V. , Das G. , Rajani M. , Mukhopadhyaya S.
Published: February 2009

We attempted percutaneous balloon mitral valvuloplasty in 50 patients (27 female and 23 male, age 10–38 years) with rheumatic mitral stenosis. The procedure could be completed in 40 patients. The failures were caused by problems related to transseptal puncture in eight cases and inability to cross the mitral valve in two cases. Immediately after valvuloplasty there was a remarkable reduction in the mean pulmonary artery pressure, left atrial mean pressure, mean diastolic gradient across the mitral valve, and the calculated pulmonary vascular resistance. The calculated mitral valve area increased and the cardiac index increased marginally. Inadequate results with a post valvuloplasty mitral valve area of 0.9 cm2 were seen in only one patient. Repeat hemodynamic evaluation in 25 patients within two weeks of valvuloplasty showed persistent benefit in all except one patient, who showed partial restenosis. Follow‐up cardiac catheterization at 3–6 months in 13 patients showed evidence of restenosis (mitral valve area <1.0 cm2 and mean diastolic gradient of > 10 mmHg) in one patient, while all others maintained hemodynamic benefit. Repeat hemodynamic evaluation at 9–18 months after valvuloplasty in eight patients showed evidence of restenosis in an additional two cases. The patients in our series are young (28 patients <20 years), small body surface area (1.35–0.2 m2), and have high left atrial and pulmonary arterial pressures.
Pacing‐induced myocardial ischemia does not affect the endothelial release of coagulant and fibrinolytic factors into the coronary circulation
Authors: Gössinger H. D. , Siostrzonek P. , Jung M. , Mösslacher H. , Speiser W. , Kyrle P. A. , Heistinger M. , Lechner K.
Published: February 2009

The present study addresses the potential effects of pacing‐induced myocardial ischemia on the secretion of coagulant and fibrinolytic factors within the coronary circulation. In 6 patients undergoing programmed ventricular stimulation with repeated induction of clinical ventricular tachycardia, the coronary release of tissue‐type plasminogen activator (t‐PA) antigen, plasminogen activator inhibitor (PAI) capacity, von Willebrand factor antigen (WF: Ag), and prostacyclin (6‐keto‐PGF la) was measured. Blood samples were collected simultaneously from the ascending aorta and the coronary sinus at baseline and immediately after the induction of ventricular tachycardia. The occurrence of pacing‐induced myocardial ischemia was established by myocardial net lactate production. Myocardial ischemia was induced in every patient by repeated pacing trials. Pacing‐induced ischemia did not affect the coronary release of any of the above factors. Consequently, there was no alteration of transcardiac gradients of thrombin‐antithrombin complexes and D‐dimer. The present results indicate that pacing‐induced myocardial ischemia does not affect the release of coagulant and fibrinolytic endothelial factors or prostacyclin into the coronary circulation.
Lipomatous hamartoma of the tricuspid valve: Echocardiographic–pathologic correlations
Authors: Crotty Thomas B. , Edwards William D. , Oh, Jae K. , Rodeheffer Richard J.
Published: February 2009

We report the eighth example of a cardiac valvular hamartoma (five mitral, three tricuspid). An intracavitary right atrial mass was present in a 76‐year‐old man and was characterized echocardiographically by a mobile cystic structure involving the septal tricuspid leaflet. Microscopically, the affected leaflet was comprised predominantly of mature adipose tissue. Formation of a valvular windsock in this case was attributed to the chronic effect of right ventricular pressure on tissue that was weaker than a normal leaflet. Valvular hamartomas should be included in the differential diagnosis of lesions that produce prolapsing, cystic, or windsock malformations of atrioventricular valves.
Normalization of reverse redistribution of thallium‐201 with procainamide pretreatment in wolff‐parkinson‐white syndrome
Authors: Nii T. , Nakashima Y. , Nomoto J. , Hiroki T. , Arakawa K. , Ohshima F.
Published: February 2009

Stress thallium‐201 myocardial perfusion imaging was performed in a patient with Wolff‐Parkinson‐White syndrome. Reverse redistribution phenomenon was observed in the absence of coronary artery disease. This seems to be the first report of normalization of this phenomenon in association with reversion of accessory pathway to normal atrioventricular conduction after pretreatment with procainamide.
Echocardiographic diagnosis of an aortic root abscess after mycobacterium fortuitum prosthetic valve endocarditis
Authors: Chow W. H. , Leung W. H. , Tai Y. T. , Cheung K. L. , Lee W. T.
Published: February 2009

A patient with an aortic root abscess complicating Mycobacterium fortuitum prosthetic endocarditis is described. The correct diagnosis had been made preoperatively by echocardiography and was confirmed subsequently at surgery.
Noise stimulus in normal subjects: Time‐dependent blood pressure pattern assessment
Authors: Germanó Giuseppe , Milito Umberto , Germanó Ugo , Giarrizzo Cesare , Santucci Anna , Damiani Silvio
Published: February 2009

Environmental noise may have various effects on blood pressure. The aim of our study was to verify noise impact on blood pressure in normal young subjects, using the “white noise” stimulus. Thirty subjects (16 males and 14 females, median age 22 years) were studied. The presence of hypertension, hypertensive hereditibility and loss of acoustic acuity were criteria for exclusion. Noninvasive measurements of systolic and diastolic blood pressure at three‐minute intervals were performed with an oscillometric system (Omega 1000, In Vivo Research), for each of four phases of the trial. After an initial rest phase (9 min) to avoid the patient's “alarm reaction,” “white noise” with an intensity equal to 40, 100, and 40 adjusted decibels (dBa) was administered consecutively for 18 min (2nd phase), 9 min (3rd phase), and 18 min (4th phase), respectively. Preliminary analysis with standard statistical tools was not able to analyze the blood pressure patterns during the test. On the contrary, polygonal analysis, taking into account the “time‐dependent” changes, showed that noise exposure (100 dBa) significantly increased systolic blood pressure in 22/30 subjects. However, systolic blood pressure rose only at the beginning of the 100 dBa exposure, indicating that stimulus changes rather than noise are key provoking factors in blood pressure increases.
Noninvasive detection of the morphologic and hemodynamic changes during normal pregnancy
Authors: Vered Zvi , Mark Poler S. , Gibson Patrick , Wlody David , Pérez Julio E.
Published: February 2009

To characterize the morphologic and hemodynamic changes during normal pregnancy, serial echocardiographic measurements (n = 210) of left ventricular (LV) dimensions and mass (M‐mode), volumes and ejection fraction (two‐dimensional), stroke volume, and cardiac output (Doppler: aortic, apical, and suprasternal) were performed in 15 patients (mean age 30 years) beginning as early as 12 weeks of gestation, at 2‐week intervals through delivery, and up to 12 weeks postpartum. Left atrial size increased from 3.4±0.4 (SD) to 3.8±0.4 cm near term, decreasing to 3.4±0.5 cm postpartum (p=0.006 overall). LV mass changes correlated with increases in body weight. No consistent significant changes in LV volumes and ejection fraction were observed. LV outflow tract cross‐sectional area increased significantly from 3.0 ± 0.2 cm2 at baseline to 3.5 ± 0.3 cm2 near term, decreasing to 3.2 ± 0.3 cm2 postpartum (p>0.002 for both). Heart rate increased from 70 ± 7 to 77 ± 10 beats/min near term decreasing to baseline postpartum (p>0.02 for both). Accordingly, cardiac output increased significantly, as detected from both the apical and suprasternal positions averaging from 4.7 ± 0.6 to 6.5 ± 1.5 1/min near term, returning to 4.3 ± 0.61/min postpartum (p>0.0005 for both). Thus, in normal pregnancy, left atrial size increases significantly without significant changes in LV dimensions, volumes, and ejection fraction. Increased LV mass is related to increased body weight. Cardiac output changes result from increased heart rate and an increase in LV outflow area, which contributes to increased stroke volume. Doppler echocardiography permits accurate detection and timing of the morphologic and hemodynamic changes during normal pregnancy.
Rupture of the left ventricular free wall following mitral valve replacement for mitral stenosis: A cause of complete (fatal) or contained (false aneurysm) cardiac rupture
Authors: Waller Bruce F. , Taliercio Charles P. , Clark Michael , Pless John E.
Published: February 2009

Complete or incomplete left ventricular free wall rupture is a known complication of mitral valve replacement. Complete free wall rupture may result in fatal bleeding, whereas imcomplete rupture may result in the formation of a pseudoaneurysm with survival possible. Two necropsy patients are described illustrating both of these complications. Proposed mechanisms for injury to the left ventricular free wall are reviewed.
Initial clinical results with the wiktor stent: A new balloon‐expandable coronary stent
Authors: Buchwald A. , Unterberg C. , Werner G. , Kreuzer H. , Wiegand V. , Voth E.
Published: February 2009

The Wiktor stent, a new coronary balloon‐expandable tantalum stent, was implanted in 17 patients for otherwise nonmanageable occlusion after balloon angioplasty (n=11) and for recurrent restenosis (n=6). Stents of 3.0 to 4.0 mm were implanted (right coronary artery: n=10, left anterior descending artery: n=4, left circumflex artery: n=2, venous graft: n=1). All patients were fully anticoagulated initially with heparin followed by Coumadin for 3 months and were treated with acetylsalicylic acid indefinitely. Due to its good radiopacity, the device could be placed easily without complications. Early occlusion occurred in one patient after 8 h probably due to friable atheromatous material prolapsing between the meshes of the stent. Late occlusion occurred in another patient who was admitted in cardiogenic shock after prehospital reanimation and was stented after occlusive dissection following balloon angioplasty of an occluded right coronary artery. In this patient with severe hypoxic brain damage, reocclusion and reinfarction to which the patient finally succumbed occurred following cessation of anticoagulation. Histology demonstrated occlusive thrombosis without evidence of a neointimal covering of the stent. Another thrombotic occlusion due to inadvertent omission of anticoagulation occurred in another patient two weeks after stenting. Control angiography after 6 months in 12 patients revealed restenosis in two patients (50% and 80%). The patient with 80% restenosis of the right coronary artery and pathologic results during stress testing underwent surgical revascularization. The other patient with a 50% restenosis of the right coronary artery was managed medically as he was asymptomatic and without evidence of ischemia during stress testing. We conclude that, due to its good radiopacity, this new stent is technically easy to implant. Restenosis rate probably lies in the range of other devices. Anticoagulation before development of a neointimal covering is necessary to prevent reocclusion.
Hemodynamic and neuroendocrine response to acute administration of the phosphodiesterase inhibitor BM 14.478 in patients with congestive heart failure
Authors: Rauch Bernhard , Zimmermann Rainer , Kapp Michael , Haass Markus , Von Molitor Stephen , Neumann Franz Josef , Kübler Wolfgang , Dietz Rainer , Tillmanns Harold , Smolarz Adalbert
Published: February 2009

: The benzimidazol analogue BM 14.478 is a phosphodiesterase inhibitor with both vasodilator and positive inotropic properties. Hemodynamic parameters and plasma hormone levels of 8 patients (1 female, 7 male) with chronic congestive heart failure NYHA Classes II‐IV (1 patient with coronary artery disease, 7 patients with primary dilated cardiomyopathy) were assessed before and until 6 h after the intravenous application of 1.0 mg BM 14.478. There was a significant decrease of mean pulmonary artery pressure (28±11 vs. 23±11 mmHg; p>0.05), mean right atrial pressure (8.6±5.2 vs. 5.0±4.7 mmHg; p>0.02), and systemic vascular resistance (1651±484 vs. 1206±252 dynes$$s$$cm–5; p>0.05) as early as 10 min after injection of BM 14.478. Pulmonary vascular resistance also was reduced (128±86 vs. 61±39 dynes$$s$$cm–5, 30 min after injection; p>0.02). Simultaneously there was a significant increase of cardiac index (2.3±0.7 vs. 3.1±0.8 1$$min–5$$m–2, 10 min after injection; p>0.02), and stroke volume index (28.8±11.7 vs. 33.9±8.5 ml$$min–1$$m–2; 30 min after injection; p>0.05). Although mean heart rate did not change significantly, some patients reacted with a transient increase. There was also a slight but insignificant increase of the double product. No serious side effects were observed.

The hemodynamic improvement was followed by a delayed reduction of plasma levels of epinephrine (51±20 vs. 41±21 pg/ml; p>0.02; 30 min after injection) and atrial natriuretic peptide (229±283 vs. 121±168 pg/ml; p>0.05; 1 h after injection). Mean levels of plasma norepinephrine, however, did not change significantly and individual responses showed large variations, which could not be predicted by the behavior of the hemodynamic parameters. Three of eight patients (2 of these with elevated baseline filling pressures) even showed a marked increase of plasma norepinephrine levels after BM 14.478. Response of plasma renin activity and plasma vasopressin levels to BM 14.478 also was heterogeneous.

According to the results of this study, acute administration of the phosphodiesterase inhibitor BM 14.478 has an immediate beneficial hemodynamic effect in patients with severe congestive heart failure by reducing both preload and afterload, and by increasing cardiac index and stroke volume. However, this improvement of hemodynamic parameters is not necessarily accompanied by a favorable short‐term response of plasma hormones, and therefore does not allow any conclusions on survival of these patients.
Progression of cardiac disease in emery‐dreifuss muscular dystrophy
Authors: Bialer Martin G. , Mcdaniel Nancy L. , Kelly Thaddeus E.
Published: February 2009

Emery‐Dreifuss muscular dystrophy (EDMD) is a rare X‐linked muscular dystrophy characterized by early contractures, progressive muscle weakness, and atrial arrhythmias. Recent reports suggest that there may be additional cardiac problems in affected males and that carrier females may also show ECG abnormalities. We restudied two large families with EDMD in order to determine the extent of these problems. We examined 10 affected males and interviewed 2 others. The 3 affected males less than 20 years old had no ECG changes. All affected men of 35 years or older had arrhythmias. One had more severe arrhythmias when asleep, indicating the usefulness of continuous 24‐h ECG monitoring in the evaluation of males affected with EDMD. Two required pacemakers, 4 had already had a pacemaker placed, and 4 other affected men with pacemakers had died prior to this study. One affected man with a pacemaker developed ventricular bigeminy and another developed congestive heart failure. Thus of 10 affected males with pacemakers, 6 had additional cardiac symptoms and 4 have died. Males with EDMD may survive longer with a ventricular pacemaker, but this may increase the likelihood that they will develop cardiomyopathy and ventricular arrhythmias. Of 34 carrier females examined, 6 had arrhythmias typical of EDMD. Two required a pacemaker. The risk of arrhythmia increased with age. Results from one family should be extrapolated to another with caution, as there appears to be significant interfamilial variation. We suggest careful cardiologic follow‐up of EDMD patients and regular cardiac evaluations for older carrier females.
Prolonged qt interval: A marker of sudden infant death syndrome?
Authors: Perticone Francesco , Ceravolo Roberto , Mattioli Pier Luigi
Published: February 2009

A prospective electrocardiographic study was performed in 1830 newborns to evaluate the predictive value of QT interval for sudden infant death syndrome (SIDS). Standard ECG, with babies asleep, was recorded at the ages of 4 days, 2, 4, 6 months, and 1 year. The QTc (±SD) was 392±22 at 4 days, 410±16 (p>0.0001) at 2 months (n=1256), 404±16 at 4 months (n= 1015), 400±16 at 6 months (n=895), and 398±15 at 1 year (n=890). QTc values longer than the mean plus 3 standard deviations were considered prolonged. Heart rate values (beats/min) were 138±19 at 4 days, 141±13 at 2 months, 134±13 at 4 months, 133±13 at 6 months, and 128±14 at 1 year. In 34 babies the QT interval was prolonged (mean + 3SD) and 3 of these died suddenly: the first, at 3 months (QTc = 470 and HR = 147 at 4 days); the second after 7 weeks (QTc = 514, HR = 115); the third at 3 months (QTc = 464 and HR = 140 at 4 days).
Is surgery for ventricular tachycardia too risky?
Authors: Van Hemel Norbert M. , Camm A. J.
Published: February 2009

There is strong evidence that recurrent symptomatic ventricular tachycardia (VT) after acute myocardial infarction is associated with a poor prognosis (1‐year mortality varying from 12% to 54%). When successive drug trials fail to suppress VT, cardiac surgery is considered but its therapeutical value appears disputable. Recent studies show inhospital mortality after surgery varying from 5% to 23%, and the 5‐year actuarial survival ranging from 33% to 71%. However, using the quality of the residual left ventricular function as criterion for operability, our recent inhospital mortality diminished to 1.3%, while the 4‐year actuarial survival was 85%. Arrhythmia freedom without drugs after 4 years after surgery is nowadays about 75%. These findings show that cardiac surgery might be a very acceptable alternative therapy in surgical candidates, in particular when one or more risk factors become apparent after acute myocardial infarction. This article describes the current position of arrhythmia surgery in relation to drug therapy and the implantable automatic defibrillator.
Diagnosis of recurrent left ventricular pseudoaneurysm by echocardiography with color flow imaging
Authors: Lasorda David M. , Dianzumba Sinda B. , Casaday Floyd M. , Joyner Claude R.
Published: February 2009

Left ventricular pseudoaneurysms are a rare complication of myocardial rupture. The diagnosis is paramount because of the propensity of pseudoaneurysms to rupture. Color flow imaging has been reported to be an aid in the diagnosis of pseudoaneurysms. We recently studied a patient with a myocardial infarction who developed a left ventricular pseudoaneurysm. Diagnosis was made by two‐dimensional imaging with color flow imaging. He subsequently had a repair procedure with a gortex graft. One week after repair, repeat echocardiography with color flow imaging showed flow into the aneurysmal sac at multiple sites, consistent with recurrence of the pseudoaneurysm. Echocardiography with color flow imaging provides a safe noninvasive diagnostic tool for evaluating pseudoaneurysms preoperatively and in assessing the competency of the repair postoperatively.
Acute myocardial infarction after simultaneous thrombosis in normal right and left coronary arteries
Authors: Serrano Carlos V. , Ramires José A. F. , Gebara Otavio C. , Cesar Luiz A. M. , Lage Silvia
Published: February 2009

A 32‐year‐old male patient with clinical and electrocardiographic evidence of acute myocardial infarction underwent coronary angiographic study. We observed nonocclusive thrombosis simultaneously in right and left anterior descending coronary arteries, without confirmation of spasm or obstructive artery disease in other coronary branches. Documentation of coronary thrombosis in more than one artery is rare, and its pathophysiology is still unknown. With the advent of thrombolytic therapy and immediate coronary angiographic studies in patients with evolving myocardial infarction, it has been possible to confirm the presence of thrombus and the type of coronary disease. In this case, we observed total lysis of both thrombi and the final aspect of “normal” angiographically reperfused coronary arteries.
The Monophasic Action Potential in Clinical Cardiology
Authors: Patterson Eugenii , Jackman Warren M. , Scherlag Benjamin J. , Lazzara Ralph , Camm A. John
Published: February 2009

Summary: For more than 30 years, the monophasic action potential has been used as an experimental tool for the study of myocardial repolarization. With recent improvements in catheter design, the utility of the tool as a means to identify the bases for ventricular arrhythmias in humans has been greatly improved. Abnormalities of repolarization leading to ventricular arrhythmia formation can be identified and specific pharmacologic therapies may be evaluated. Further evaluation of the technique by cardiac electrophysiologists may improve both the diagnosis and the treatment of ventricular arrhythmias dependent upon afterdepolarization formation (acquired and familial long QT syndromes).
Cardiac Tamponade as an Unusual Presentation of Lung Cancer: Case Report and Review of the Literature
Authors: Huntsman W. Thomas , Brown M. L. , Albala David M.
Published: February 2009

Summary: A case of cardiac tamponade as an unusual presentation of lung cancer and a review of the current literature are presented.
Cocaine: The Newest Risk Factor for Cardiovascular Disease
Authors: Cregler Louis L.
Published: February 2009

Summary: Cocaine‐related cardiovascular events escalated during the 1980s as cocaine became purer, cheaper, and easier to obtain. Cocaine abuse is a risk factor for myocardial ischemia and/or infarction, cardiac arrhythmias, pulmonary edema, ruptured aortic aneurysm, cerebral infarction, infective endocarditis, vascular thrombosis, myocarditis, and dilated cardiomyopathy. As medical and social complications of cocaine have become evident, and with the growing negative image of cocaine, the number of first‐time users has begun to decline. Cocaine abuse is seen on all levels of our society and has emerged as an issue of significant medical and public health importance. All routes and forms of cocaine abuse are potentially cardiotoxic and can be lethal. Fatal cardiac complications can occur in a first‐time user. All physicians should be alert for cocaine abuse when confronted with unexplained cardiac symptoms. Cocaine is the newest and sometimes unrecognized risk factor for cardiovascular disease in young individuals otherwise free of cardiovascular risk factors.
The Prognostic and Economic Implications of a Strategy to Detect and Treat Asymptomatic Ischemia: The Atenolol Silent Ischemia Trial (ASIST) Protocol
Authors: Pepine Carl J. , Cohn Peter F. , Deedwania Prakash C. , Gibson Robert S. , Gottlieb Sidney O. , Handberg Eileen , Hill James A.
Published: February 2009

Summary: Although silent ischemia may be linked to increases in cardiovascular morbidity and mortality, the long‐term effects of a strategy aimed at the detection and treatment of this asymptomatic condition have not been fully explored. We therefore have developed the Atenolol Silent Ischemia Trial (ASIST), the first multicenter, randomized, prospective study of the prognostic implications of silent ischemia in asymptomatic and minimally symptomatic patients with coronary artery disease. Inclusion criteria for study patients were documented coronary artery disease, evidenced angiographically or by previous myocardial infarction, and transient ischemia, evidenced by abnormalities of regional wall motion, stress thallium‐201, or exercise electrocardiogram. The main objective of ASIST is to assess the influence of frequency and duration of symptomatic and asymptomatic ischemic episodes on the occurrence of fatal and nonfatal cardiac events. Atenolol, a beta1‐selective adrenergic blocker, was chosen as the therapeutic intervention because of its potential benefits in treating both symptomatic and asymptomatic ischemia. Ambulatory electrocardiographic monitoring will be used to measure the frequency and duration of ischemic episodes during daily life. The predictive ability of short‐term (4‐week) effects on long‐term (52‐week) response to atenolol treatment is also being assessed, along with the economic impact of this diagnostic and therapeutic strategy. Given the current emphasis on reducing morbidity and mortality associated with coronary artery disease, ASIST results should shed light onto the long‐term management and prognostic implications of this otherwise asymptomatic condition.
Acute effects of the ACE inhibitorlisinopril on cardiac electrophysiological parameters of isolated guinea pig hearts
Authors: Stark G. , Stark U. , Nagl S. , Klein W. , Pilger E. , Tritthart H.A
Published: February 2009

Angiotensin‐converting enzyme (ACE) in‐hibitors are of benefit in life‐threatening ventricular ar‐rhythmias in patients with congestive heart failure and ven‐tricular tachycardia caused by the onset of myocardialischemia as well as by reperfusion of an ischemic area. The aim of the present study was to investigate whether di‐rect electrophysiological effects are responsible for these observations. Therefore, we investigated the electrophysi‐ological effects of lisinopril on the whole cardiac conduc‐tion and pacemaker system in isolated guinea pig hearts perfused by the method of Langendorff at concentrations of 0.01, 0.1, 1, and 10 μM. Lisinopril did not affect heart rate, atrioventricular, His bundle, or intraventricular conductionat any of the concentrations tested. Likewise the frequency‐dependent QT duration was unchanged. At a concentra‐tion of 10 pM, lisinopril prolonged effective refractory pe‐riod evaluated by premature beats (46 ± 15%, n = 8, p < 0.01) as well as the rate‐dependent effective refractoryperiod (31 ± 12, n = 8, p < 0.0l) of the atrioventricular con‐duction. These effects can be explained by lisinopril's ac‐tion as a minor calcium antagonist at a toxic concentrationof 10 μM. The present results show that electrophysiolog‐ical parameters are not substantially altered by lisinopril.Therefore, several other mechanisms such as the unloadingof the left ventricle and/or the suppression of noradrenalinrelease and the electrolyte (potassium and magnesium) re‐pletion and/or regression of left ventricular hypertrophy aslong‐term effects may play a major role in the antiarrhyth‐mic efficacy of ACE inhibitors.
Effects of atrioventricular block on ventricular fibrillation threshold in dog
Authors: Kumagai Koichiro , Tashiro Eiichiro , Moroe Kazuo , Hiroki Tadayuki , Arakawa Kikuo
Published: February 2009

The effects of complete atrioventricular block (CAVB) on ventricular vulnerability were studied 1 week after a transcatheter electrical ablation of the AV junction in 18 closed‐chest dogs. All dogs exhibited CAVB and a stable ventricular escape rhythm with a mean cycle length of 1795±600 ms. Although QT interval during CAVB was significantly prolonged compared with that during the sinus rhythm, QTc interval was significantly shortened. The ventricular fibrillation threshold was significantly elevated after creation of the block (from 9.35±2.28 to 12.3±3.69 mA, p < 0.01). Thus, CAVB which is not associated with QTc prolongation would be even less likely to play an important role in producing ventricular fibrillation presumably including torsades de pointes or polymorphous ventricular tachycardia.
Management of coronary heart disease in the elderly
Authors: Rogers, Ward B. , Von Dohlen, Thomas W. , Frank, Martin J.
Published: February 2009

The prevalence of coronary heart disease (CHD) increases rapidly with advancing age and remains the major cause of death among elderly Americans. The number of elderly has doubled in the last 30 years and is projected to continue growing at more than twice the rate of the general population. The resources required in managing CHD in this population will reach astronomical levels during the next few decades and will severely tax our ability to provide adequate medical care to all citizens, unless cost effective diagnostic and therapeutic strategies are developed which do not severely compromise health care. Risk factors for CHD should be identified and modified as early in life as possible. Modification of risk factors begun at advanced age appears to confer benefit, however. Anti‐ischemic drug therapy is the treatment of choice for patients with mild or moderate stable angina. Select elderly may be willing to accept the increased risks of coronary revascularization to achieve relief from debilitating angina or prolongation of life. Physicians must use care in planning diagnostic and therapeutic strategies. Quality of life and independence are often more important considerations than longevity in this age group.
Changes in left atrial size in patients with lone atrial fibrillation
Authors: Suarez, Guillermo Sosa , Lampert, Steven , Ravid, Shmuel , Lown, Bernard
Published: February 2009

A retrospective analysis was performed on 23 subjects with lone atrial fibrillation who were followed for an average of 6.2 years (1.1–12.8 years). In all patients, underlying organic heart disease was excluded based on history, physical exam, electrocardiogram, echocardiogram, and Doppler ultrasound interrogation. All patients had at least two echocardiographic studies during the period of observation. Atrial fibrillation was chronic in 11 subjects and paroxysmal in 12. All echocardiographic measurements were obtained by averaging the measurements of two blinded investigators. Left atrial size increased an average of 5.6 mm which translates into a 14.7% increase over the baseline measurement. This increase in size was not associated with a change in left ventricular mass or fractional shortening as determined by echocardiography. Subjects with chronic atrial fibrillation had a larger percent increase than subjects with paroxysmal atrial fibrillation (18.9 vs. 10.8%), although this relative change in size failed to reach statistical significance. The only variable which significantly contributed to the change in left atrial size was the duration of follow‐up. We conclude that atrial fibrillation occurring in patients with lone atrial fibrillation may cause a slow and progressive increase in left atrial size independent of changes in left ventricular size or function.
Heart rate variability: An important new risk factor in patients following myocardial infarction
Authors: John Camm, A. , Ewing, D. J.
Published: February 2009

After acute myocardial infarction, cardiac autonomic, and particularly parasympathetic, activity decreases, followed by a gradual return toward normal over the next few weeks and months. The easiest measureable index of autonomic activity is heart rate variability, which can be assessed in a number of different ways. Where heart rate variability is low after myocardial infarction, long‐term survival is considerably reduced, independent of other known risk factors. This may be caused by patchy autonomic denervation, rendering the heart more susceptible to potentially fatal arrhythmias. Prophylactic drug therapy might reduce mortality in patients with low heart rate variability.
Catheter balloon valvuloplasty of stenotic porcine bioprosthetic valves: Part I: anatomic considerations
Authors: Waller, Bruce F. , Mckay, Charles , Tassel, James Van
Published: February 2009

During the last several years, dilating balloons have been applied in the treatment of stenotic cardiac valves. This interest has recently been extended to stenotic porcine bioprosthetic valves. Part I of this review discusses the pathologic processes responsible for degeneration of porcine prostheses: intrinsic calcification (mineralization), cuspal tears and perforations, and cuspal thrombosis (non‐infective). These changes form the basis of applied balloon valvuloplasty techniques.
The stunned and hibernating myocardium: A brief review
Authors: Richard Conti C.
Published: February 2009

Definitions: Stunned myocardium is viable myocardium salvaged by coronary reperfusion that exhibits prolonged postischemic dysfunction after reperfusion. Hibernating myocardium is ischemic myocardium supplied by a narrowed coronary artery in which ischemic cells remain viable but contraction is chronically depressed.

Clinical evidence: Stunned myocardium has been identified in the following patient groups: (1) thrombolysis or percutaneous transluminal coronary angiography (PTCA) in patients with acute evolving infarction; (2) unstable angina; (3) exercise‐induced angina; (4) coronary artery spasm; (5) platelet aggregation or transient thrombosis of a coronary artery; (6) PTCA for chronic myocardial ischemia; and (7) immediately following coronary artery bypass graft (CABG). Evidence of hibernating myocardium (LV dysfunction) is found in the patient with severe coronary artery stenosis, even in asymptomatic patients at rest. Stunned myocardium returns to normal after a prolonged period of time (hours to weeks). Hibernating myocardium returns to normal function rather quickly if the cause is removed.

Differentiation: Stunned myocardium can be differentiated from hibernating myocardium by three clinical parameters, namely, LV wall motion, myocardial perfusion, and myocardial metabolism. Stunned myocardium has abnormal wall motion that tends to normalize in response to inotropes and postextrasystolic potentiation. Perfusion is adequate and metabolism is also adequate. Hibernating myocardium also has abnormal wall motion, which normalizes after nitrates, inotropes, post extrasystolic potentiation (PESP), PTCA, or CABG. Myocardial perfusion is reduced but can be reversed with PTCA or CABG and metabolism is adequate.
24‐hour blood pressure profiles in hypertensive patients administered ramipril or placebo once daily: Magnitude and duration of antihypertensive effects
Authors: Mccarron David ,   The Ramipril Multicenter Study Group
Published: February 2009

Ramipril is a new, potent nonsulfhydryl inhibitor of angiotensin converting enzyme. The magnitude and duration of its antihypertensive effect were evaluated in a multicenter, placebo‐controlled, randomized clinical trial conducted in 100 patients with mild to moderate essential hypertension. Ramipril significantly reduced both supine and standing blood pressures measured 24 h after dosing. Automated blood pressure monitoring showed that ramipril significantly reduced systolic and diastolic pressures for 24 h after dosing. The peak effect occurred between 3 and 6 h after dosing, with approximately 50% of this effect retained after 24 h. Ramipril was well tolerated; there was no significant difference between active drug and placebo in the overall incidence of side effects. Ramipril is an effective and well‐tolerated antihypertensive agent, which reduces both supine and standing blood pressure over the entire 24‐h period after dosing.
Repetitive reentrant and non‐reentrant ventriculoatrial synchrony in dual chamber pacing
Authors: Serge Barold S.
Published: February 2009

Repetitive retrograde ventriculoatrial (VA) conduction in patients with dual chamber pacemakers may cause two forms of VA synchrony. (1) Endless loop tachycardia (pacemaker‐mediated tachycardia) or repetitive reentrant VA synchrony occurs when the pacemaker senses retrograde P waves. Appropriate programming can prevent pacemaker reentrant tachycardia in almost all cases. However, the measures used to control tachycardia may themselves create new problems. (2) AV desynchronization arrhythmia or repetitive non‐reentrant AV synchrony occurs when the pacemaker does not sense retrograde P waves. In this form of VA synchrony, the atrial stimulus is ineffectual because it falls in the atrial myocardial refractory period generated by the preceding unsensed retrograde P wave. A long atrioventricular interval and a relatively fast lower rate (or sensor‐driven rate with DDDR pacing) favor the development of AV desynchronization arrhythmia and its unfavorable hemodynamic consequences.
Critical noise level reduction for correct identification of late potentials: An illustrative case report
Authors: Kulakowski Piotr , Murgatroyd Francis D. , John Camm A.
Published: February 2009

The precision of detection of late potentials (LPs) on signal‐averaged electrocardiography (SAECG) depends on the degree of noise reduction. The recommended low‐noise endpoint is 0.3 μV. We describe a patient with sustained ventricular tachycardia after myocardial infarction with very low amplitude LPs in whom a noise level lower than 0.3 μV was necessary in order to obtain an abnormal result of the SAECG. The presence of LPs was confirmed by spectral temporal mapping of the SAECG.
The influence of the presence of collaterals on restenoses after PTCA
Authors: Probst Peter , Baumgartner Christoph , Gottsauner‐Wolf Michael
Published: February 2009

To assess the influence of collaterals on the long‐term follow‐up after successful percutaneous transluminal coronary arteriography (PTCA), 120 consecutive patients were studied. Of these, 104 (87%) had an adequate reangiogram and were included. At the time of PTCA the collaterals were estimated by a scoring system. In addtion, the coronary wedge pressure was measured in 49 patients six months after PTCA, a follow‐up angiogram was performed, and the patients were split up into a group with restenoses (stenosis >50%), 34 patients (32.7%); and a group without restenoses (stenosis <50%), 70 patients (67.3%). A total of 35 patients (30.7%) had collaterals. A comparison between both groups showed no significant differences in clinical parameters (age, angina duration, vessel involvement, lipids, blood sugar, and blood pressure), and stenoses‐related parameters (degree of stenoses, eccentricity, balloon size, inflation pressure, dissection, gradient after dilatation, and residual stenoses). Patients with collaterals had a significantly higher incidence of restenoses than those without collaterals (45.7% vs. 26.1%, p<0.05). Patients with wedge pressure of <45 mmHg (n = 30) had a significantly lower restenosis rate (23.3%) than patients with a coronary wedge pressure of >45 mmHg (n= 19) (restenosis rate 52.6%). It is concluded that the presence of collaterals indicates a high restenosis rate after PTCA within 6 months.
Operations for Atrial Fibrillation
Authors: John Camm A. , Cox James L. , Boineau John P. , Schuessler Richard B. , Bruce Ferguson T. , Cain Michael E. , Lindsay Bruce D. , Corr Peter B. , Kater Kathy M. , Lappas Demetrios G.
Published: February 2009

Atrial fibrillation is the most common of all sustained cardiac arrhythmias, yet it has no effective medical or surgical therapy. During the past decade, multipoint computerized electrophysiological mapping systems were used to map both experimental and human atrial fibrillation. On the basis of these studies, a new surgical procedure was developed for atrial fibrillation. Between September 25, 1987, and May 1, 1991, this procedure was applied in 22 patients with either paroxysmal atrial flutter (n = 2). paroxysmal atrial fibrillation (n= 11), or chronic atrial fibrillation (n = 9) of 2 to 21 years' duration. All patients were refractory to all antiarrhythmic medications and each patient failed an average of 5.2 drugs preoperatively. There were no operative deaths and all perioperative morbidity resolved. All 22 patients have been cured of atrial fibrillation with surgery alone. One late isolated episode of atrial flutter occurred in a patient who is now receiving encainide. Preservation of atrial transport function has been documented in all of the patients postoperatively and all have experienced marked clinical improvement.
Perforated ventricular aneurysm in a male suffering from pneumonia
Authors: Eber Bernd , Neumann HansjÖRg , Dusleag Johann , Klein Werner , Rigler Bruno
Published: February 2009

In a 49‐year‐old male with fever, dyspnea, and chest pain, thoracic x‐ray revealed pneumonia with enlarged heart silhouette. Antibiotics were successful, pneumonia healed and complaints disappeared. Yet, during the following 3 months, echocardiography showed mild persistent pericardial effusion while in ECG both sinus tachycardia and ST‐T changes were found suggesting chronic pericarditis. Magnetic resonance imaging, however, revealed an extensive posterobasal aneurysm with pericardial effusion substantiated by ventriculography. Coronary angiography showed diffuse three‐vessel disease. Surgery revealed aneurysm with distinct perforation of the left ventricle and pericardial thrombi, thus aneurysmectomy as well as bypass grafts were performed. One year postoperatively, magnetic resonance imaging confirmed the absence of aneurysm with only a small irreversible posterobasal perfusion defect remaining as shown by thallium scintigraphy.