bluuebunny/crossref_metadata_2025 huggingface dataset:
The implantable defibrillator and antiarrhythmic drugs—competitive and complementary treatment for severe ventricular arrhythmia
Authors: Dorian Paul , Newman David
Published: February 2009

Most patients with a history of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) are at high risk of recurrence. Implanted defibrillators (ICDs) are highly effective in sensing and converting VT or VF to a perfusing rtrythm. “Conventional” antiarrhythmic agents, which primarily block cardiac sodium channels, are relatively ineffective in preventing arrhythmia recurrence; amiodarone and sotalol appear to be effective in reducing recurrence and mortality rates, although the extent of benefit is not well understood. Despite the apparent advantage of ICDs, they have short‐ and long‐term complications, are costly, and their benefit in prolonging the quantity or quality of life remains unproven. Randomized clinical trials which compare the effect of ICDs with that of antiarrhythmic drugs on mortality, cost, and quality of life will be necessary to understand how patients with malignant arrhythmias ought to be treated. If an ICD is implanted, adjunctive therapies need to be considered to treat the underlying heart disease and to derive optimum benefit from the device. Drugs may have beneficial or adverse interactions with devices, and the full understanding of these interactions requires further study.
Coronary artery fistula related to dilatation of totally occluded vessel
Authors: Saad Robert M. , Jain Avanindra
Published: February 2009

Percutaneous transluminal coronary angioplasty (PTCA) is widely used to treat patients with coronary artery disease. Experience and improvement in catheters has led to its wider utilization. A case of coronary recanalization, complicated by coronary fistula created by an angioplasty guidewire, is reported.
The utility of nitroderm® TTS® in angina pectoris: Long‐term treatment after switching from long‐acting oral isosorbide dinitrate
Authors: Hayashi H. , Ito T. , Matsubara T. , Watanabe T. , Kuzuya F. , Mizuno Y. , Sotohata I. , Fujinami T. , Toyama J. , Yamada K.
Published: February 2009

Long‐acting oral isosorbide dinitrate (ISDN) was replaced by Nitroderm® ITS®, and the utility of this drug in long‐term treatment was assessed in 69 patients with angina pectoris. The frequency of attacks (p < 0.001) and the consumption of sublingual nitrate tablets (p < 0.01) were found to be significantly lower at 2 weeks to 6 months than in the observation period in patients who experienced attacks or received sublingual tablets during the observation period. On the other hand, no significant time‐lapse changes from the observation period were noted in patients who experienced no attacks or received no sublingual tablets during the observation period. The symptoms of adverse effects were mild. The improvement rates (improved) of subjective symptoms and electrocardiogram (ECG) in Group A were about 50% after 6 months. On the other hand, the improvement rates (not aggravated) of subjective symptoms and ECG in Group B were more than 90%. Nitroderm TTS is considered a useful plaster preparation which can be used for sufficiently extended periods of time because its efficacy was as high as, or higher than, that of oral ISDN when this drug was administered over a long period of time after a switch from longacting oral ISDN in angina pectoris patients.
A randomized pilot trial of low‐dose combination lipid‐lowering therapy following coronary artery bypass grafting
Authors: BARBIR M. , HUNT BEVERLEY J. , GALLOWAY D. , TAYLOR ALISON , ILSLEY C. , MITCHELL A. , YACOUB M.
Published: February 2009

Vein graft atherosclerosis is a common and serious complication of coronary artery bypass grafting (CABG). There is mounting evidence that lipoprotein abnormalities play an equally important role in the development of lesions in saphenous vein grafts after CABG as in native coronary vessel disease. The potential benefit of low‐dose lipid lowering combination therapy in these patients has not been investigated. In a randomized, double‐blind, placebo‐controlled study, we compared the efficacy and safety of a low‐dose combination of colestipol 10 g and simvastatin 10 mg/day (CS) to colestipol 10 mg and bezafibrate 400 mg/day (CB) for 2 months in 33 patients with serum total cholesterol > 6.5 mmol/l and triglyceride < 4.5 mmol/l who had undergone CABG for severe coronary artery disease. In the CS group, total cholesterol decreased by 29% and low‐density lipoprotein (LDL) cholesterol by 42%; similarly, CB reduced total cholesterol by 17%, LDL cholesterol by 23%, triglyceride by 19%, and increased high‐density lipoprotein (HDL) cholesterol by 14%. Lipoprotein (a) and hemostatic factors were unaffected by either therapy in this study. Both combination therapies were well tolerated with no significant clinical or biochemical side effects. We conclude that low‐dose combinations of colestipol and simvastatin or colestipol and bezafibrate are effective and well tolerated in the management of moderate hyperlipidemia in patients who had undergone CABG.
Torsade de pointes complicating drug treatment of low‐malignant forms of arrhythmia: Four case reports
Authors: Faber T. S. , Zehender M. , Van Loo A. De , Hohnloser S. , Just H.
Published: February 2009

In patients with malignant ventricular arrhythmias, antiarrhythmic therapy is known to carry a substantial risk of proarrhythmia. This risk is usually considered to be low when supraventricular arrhythmias or benign ventricular arrhythmias are considered. We were able to collect data on four patients without a history of life‐threatening arrhythmias, in whom antiarrhythmic therapy was used and resulted in documented ventricular fibrillation or torsade de pointes. In Cases No. 1 and 2, atrial fibrillation was treated with either quinidine or quinidine and sotalol in combination. In both patients Holter monitoring, 4‐12 h after conversion to sinus rhythm, documented the spontaneous occurrence of torsade de pointes degenerating into ventricular fibrillation and requiring DC shock for termination. In Case No. 3, atrial fibrillation was treated with sotalol and amiodarone for 2 months when incessant episodes of torsade de pointes were documented. In Case No. 4, frequent but unsustained ventricular arrhythmias were treated with amiodarone in a patient suffering dilative cardiomyopathy. After 6 days of treatment at a heart rate of 54 beats/min, a marked QT increase was associated with the occurrence of repetitive episodes of polymorphic ventricular tachycardia degenerating into ventricular fibrillation. None of the patients presented significant electrolyte abnormalities in the laboratory. A pathologic increase of the QTc‐time was documented in Cases No. 1, 3, and 4. In all patients antiarrhythmic therapy was withdrawn after the proarrhythmic event and the patient became free of malignant tachyarrhythmias. Antiarrhythmic therapy also carries a considerable risk of proarrhythmia when “benign” cardiac arrhythmias are treated. The risk seems to be lower than in patients with malignant arrhythmias, however it includes the occurrence of lethal tachyarrhythmias. Special attention should be paid to the selection of antiarrhythmic agents when used in combination.
Noninvasive localization of accessory pathways by magnetocardiographic imaging
Authors: Nomura Masahiro , Nakaya Yutaka , Saito Ken , Kishi Fumiko , Watatsuki Tetsuzo , Miyoshi Hirokazu , Nishikado Akiyoshi , Bando Shigenobu , Ito Susumu , Nlshltanl Hiromu , Wada Masao , Fujita Satoshi , Tamura Itsuro
Published: February 2009

The magnetocardiogram (MCG) is a newly developed method that helps localize a cardiac current source. To test the clinical accuracy of a 7‐channel biomagnetic system in the localization of early ventricular depolarization sites, the MCGs of 14 patients with Wolff‐Parkinson‐White (WPW) syndrome were recorded in a radiofrequency‐shielded room. The locations of early ventricular depolarization sites were classified by standard 12‐lead electrocardiograms (ECGs) and body surface iso‐potential mapping. The accessory pathways of 3 patients with WPW syndrome were located in the right free wall and in 11 patients in the left free wall. The three‐dimensional (3‐D) dipole location was computed every 2 ms from the onset of the QRS complex by the least‐square method. These 3‐D dipole locations were projected onto a gated magnetic resonance image in order to visualize the propagation of the calculated ventricular source. The results were compared with those obtained by body surface isopotential mapping, and electrocardiographic and electrophysiologic studies. The location of the deduced current dipole at 20 ms correlated well with the location of the accessory pathway by the body surface mappings in 12 of the 14 patients with WPW syndrome. The MCG is capable of precisely determining the 3‐D location of a current source in a noninvasive manner and may be of potential benefit in the treatment of WPW syndrome by catheter ablation.
Bisoprolol, a once‐a‐day beta‐blocking agent for patients with mild to moderate hypertension
Authors: Davidov Michael E. , Singh Sant P. , Vlachakis Nicolas D. , Blumenthal Jerome B. , Simon Joseph S. , Bryzinski Brian S. , Koury Kenneth J. , Alemayehu Demissie
Published: February 2009

The 24‐h blood pressure control of bisoprolol, a new beta1‐selective, beta‐blocking agent, was studied in 240 mild to moderate hypertensive patients in this 4‐week, randomized, double‐blind, placebo‐controlled trial. A once‐daily dosing schedule was evaluated by comparing bisoprolol's antihypertensive effectiveness and safety at 24 h postdose and 3 h postdose, the latter time intended to correspond to peak effectiveness. Results from this trial demonstrated the antihypertensive effectiveness of once‐daily bisoprolol at doses ranging from 5‐20 mg. Mean reductions from baseline diastolic blood pressure, measured 24 h postdose, were 6.3,8.8, and 10.1 mmHg for patients receiving bisoprolol 5, 10, and 20 mg, respectively, compared with 1.6 mmHg for placebo‐treated patients (p< 0.01); mean reductions from baseline systolic blood pressure for the bisoprolol groups were 8.6, 8.6, and 10.9 mmHg, respectively, versus 3.3 mmHg for placebo (p≤0.01); and mean reductions from baseline heart rate for the bisoprolol groups were 5.1,7.1, and 10.2 beats/min, respectively, compared with a 0.9 beats/min increase in heart rate for the placebo group (p < 0.01). The response rates for bisoprolol‐treated patients ranged from 47 to 70% compared with 18% for patients on placebo (p < 0.01). Antihypertensive effects were dose‐related and sustained over the 24‐h dosing interval. Near maximal antihypertensive effects were achieved within 1 week of initiation of therapy with bisoprolol and were sustained over the course of the trial.

The antihypertensive effects of bisoprolol were accompanied by a favorable safety profile. Furthermore, bisoprolol was welltolerated and did not differ significantly from placebo in either the frequency or severity of reported adverse experiences. Withdrawal rates for adverse events were 1.4% for the placebo group versus 1.9% for the composite bisoprolol group. Laboratory changes generally were related to small increases within the normal range and were not clinically relevant. No bisoprolol‐treated patient left the study or interrupted treatment for a clinical laboratory abnormality.
Urinary carnitine excretion in patients with heart failure
Authors: Matsui Shinobu , Sugita Toshiro , Matoba Munetoshi , Murakami Eiji , Takekoshi Noboru , Shinka Toshihiro , Matsumoto Isamu
Published: February 2009

To evaluate the fatty acid metabolism in heart failure, the semiquantitative analysis of urinary free carnitine and acylcarnitine was made by fast atom bombardment mass spectrometry (FABMS) in 22 patients (mean age 67.3 years) with heart failure and 19 age‐matched healthy controls (average age 60.4 years). Urinary excretion of free carnitine was 0.20 ± 0.118 ratio/mg creatinine in the healthy controls and 1.32 ± 1.170 ratio/mg creatinine in the patients with heart failure. The latter value was significantly higher (p < 0.01 ). Patients with heart failure were classified into two groups according to the urinary free carnitine concentration. One was the high excretion group (2.19 ± 0.102 ratio/mg creatinine, 12 cases) and the other was the low excretion group (0.37 ± 0.212 ratio/mg creatinine, 10 cases). In the high excretion group, urinary acetylcarnitine was also increased, but no significant abnormalities were observed in the urinary organic acid profile. In the high group, 1 patient was classified as NYHA class III and 11 as NYHA class IV. Four patients died in the hospital. In the low excretion group, five patients were classified as NYHA class III and five as NYHA class IV. Only one patient died in the hospital. In the high group, patients with severe and prolonged heart failure tended to maintain higher values of urinary free carnitine. We could not find any abnormalities in fatty acid metabolism in patients with heart failure, but it is suspected that the patients who excrete large amounts of free carnitine into the urine, namely the patients with severe heart failure, have some possibility of carnitine deficiency.
Fatal intracerebral hemorrhage following thrombolytic therapy of embolic myocardial infarction in unsuspected infective endocarditis
Authors: Di Salvo Thomas G. , Tatter Stephen B. , O'Gara Patrick T. , Nielsen Gunnlaugur P. , Desanctis Roman W.
Published: February 2009

Cerebral hemorrhage occurs in 0.2% of patients under the age of 60 years treated with thrombolytic therapy for acute myocardial infarction. A case of fatal cerebral hemorrhage following TPA therapy for myocardial infarction due to probable coronary artery embolism during unsuspected native valve infective endocarditis is reported.
Lactate threshold is not an onset of insufficient oxygen supply to the working muscle in patients with chronic heart failure
Authors: Yamabe Hiroshi , Itoh Kazushi , Yasaka Yoshinori , Takata Teruo , Yokoyama Mitsuhiro
Published: February 2009

It has been argued that the lactate threshold (LT) serves as an index to reflect circulatory insufficiency in transporting oxygen during submaximal exercise in patients with chronic heart failure (CHF). We examined whether or not the LT was related to an insufficient oxygen supply in patients with CHF. Sixty‐nine patients were divided by NYHA classification. All underwent invasive cardiopulmonary exercise testing. The rate of increase in oxygen delivery (O2D) versus VO2 (ΔO2D/ ΔVO2) was significantly lowered when work rate exceeded LT, that is, 1.32 ± 0.35 to 1.05 ± 0.37 (p < 0.01), 1.22 ± 0.40 to 0.98 ± 0.40 (p < 0.05), and 1.04 ± 0.26 to 0.78 ± 0.39 (p < 0.05) in NYHA classes I, II, and III, respectively. However, the rate of increase in leg O2D versus leg VO2 (ΔLO2D/ΔLVO2) did not change, that is, 1.25 ± 0.20 to 1.29 ± 0.20 (NS), 1.27 ± 0.23 to 1.21 ± 0.28 (NS), and 1.19 ± 0.24 to 1.15 ± 0.17 (NS) in classes I, II, and III, respectively. Leg venous PO2 was significantly different among three groups, that is, 23.7 ± 3.4 mmHg, 23.2 ± 2.8 mmHg, and 20.1 ± 2.3 mmHg (p < 0.001), respectively. Thus, the oxygen supply to the working muscle did not become insufficient when work rate exceeded LT, and the LT occurred at different levels of leg PO2. It was concluded that the LT was not a result of anaerobiosis in patients with CHF.
Postoperative hemodynamic improvement with paced linkage of the donor and recipient hearts following heterotopic cardiac transplantation
Authors: Cowell R. , Morris‐Thurgood J. , Coghlan J. , Paul V. , Mitchell A. , Khaghani A. , Ilsley C. , Yacoub M.
Published: February 2009

It has been shown that following heterotopic heart transplantation the recipient left ventricle ejects more effectively when it contracts out of phase with the donor left ventricle. However, this is rarely the situation, as the two hearts beat independently of one another and the denervated donor heart tends to beat faster than the recipient. In this study the hemodynamic effects of connecting the two hearts by an external temporary dual‐chamber pacemaker were evaluated. The donor right ventricle was sensed and the recipient right atrium paced after a timed delay. The delay was adjusted so that recipient systole coincided with donor diastole. Eleven patients were studied in the first postoperative day. Pacing resulted in an improvement in cardiac output from 5.0 to 5.61/min (p = 0.003) and a reduction in pulmonary capillary wedge pressure from 16 to 12 mmHg (p = 0.0035). This was associated with a 35% reduction in inotrope requirements. It is concluded that sequential pacing of the two hearts is a useful adjunct to inotropic support in the postoperative period.
The severity of residual coronary stenosis immediately after thrombolytic therapy does not influence the size of later left ventricular asynergic area
Authors: Fukunaga Takashi , Hanada Yuhji , Koiwaya Yasushi , Eto Tanenao
Published: February 2009

To determine whether the severity of residual coronary artery stenosis immediately after thrombolytic therapy influences the size of later left ventricular (LV) asynergic area, we reviewed coronary angiograms (CAGs) and left ventriculograms (LVGs) of 31 patients with acute myocardial infarction (AMI). All patients received intracoronary urokinase therapy within 6 h after onset of AMI due to total occlusion of the proximal left anterior descending coronary artery (LAD). A dose of 960,000 IU urokinase was infused into the ostium of the left coronary artery over 40 min. Patients in whom antegrade blood flow without delayed distal filling was restored received rigorous anticoagulation. The patients were divided into three groups according to the severity of the coronary lesion immediately after urokinase therapy: 9 patients with complete occlusion in Group 1, 15 with > 90% stenosis in Group 2, and 7 with <90% stenosis in Group 3. There were no significant differences in the baseline clinical characteristics among the patients in the three groups. The LADs in Group 1 were also totally occluded 1 month after urokinase therapy, the treated vessels in both Groups 2 and 3 were still patent, and patients in Group 2 showed a further reduction in residual stenosis. When LV asynergic area, regional wall motion, and global ejection fraction (EF) were compared among the three groups, no significant differences were demonstrated. in comparison with the data immediately after urokinase therapy, all parameters 1 month after therapy were significantly improved in both Groups 2 and 3. However, there was no significant difference in the improvement of these parametere between Groups 2 and 3 despite significant differences in residual stenosis of the LADs immediately after urokinase
Noninvasive evaluation of contractile state by left ventricular dP/dtmax divided by end‐diastolic volume using continuous‐wave doppler and M‐mode echocardiography
Authors: Kawai Hiroya , Yokota Yoshiyuki , Yokoyama Mltsuhiro
Published: February 2009

The maximum rate of left ventricular (LV) pressure rise (dP/dtmax) is commonly used in the assessment of directional change in LV contractility and, recently, estimated by analyzing continuous‐wave Doppler ultrasound velocity curve of mitral regurgitation. As an alteration in ventricular preload is known to affect dP/dtmax, normalized dP/dtmax for preload might be more reliable to assess LV contractile state. To investigate the usefulness of a new index of LV contractile state determined by continuous‐wave Doppler analysis of mitral regurgitation and M‐mode echocardiogram‐derived LV end‐diastolic volume, we studied 18 patients with mild mitral regurgitation. The continuous‐wave Doppler velocity curves of mitral regurgitation were digitized and converted to instantaneous pressure gradient between the LV and left atrium using the simplified Bernoulli equation. The maximum value of its first derivative (Doppler‐derived dP/dtmax) correlated well with LV dP/dtmaxusing simultaneously recorded LV pressures by manometer‐tipped catheter (n = 20, r = 0.97, p < 0.001). Corrected Doppler‐derived dP/dtmax for LV end‐diastolic volume using Teichholz's method significantly increased by inotropic stimulation with dobutamine (p < 0.01); however, it remained unchanged by augmentation of afterload with angioteasin II. Thus, the LV dP/dtmax can be accurately estimated in humans by analyzing the continuous wave Doppler velocity curve of mitral regurgitation, and corrected Doppler‐derived dP/dtmax for LV end‐diastolic volume is relatively independent of loading alteration and sensitive to inotropic stimulation. We concluded that echocardiographic assessment by combined Doppler‐ and M‐mode measurements provides a useful and sensitive index of LV contractile state noninvasively.
Pathology of tricuspid valve stenosis and pure tricuspid regurgitation—Part I
Authors: Waller Bruce F. , Howard Jane , Fess Stephen
Published: February 2009

This three‐part article examines the histologic and morphologic basis for stenotic and purely regurgitant tricuspid valves. In Part I, conditions producing tricuspid valve stenosis are reviewed. In over 90% of stenotic tricuspid valves, the etiology is rheumatic disease. In isolated tricuspid stenosis, the etiology is either carcinoid or congenital. Rare causes of tricuspid stenosis include active infective endocarditis, metabolic or enzymatic abnormalities (Fabry's, Whipple's disease), and giant blood cysts.
Enoximone versus epinephrine/nitroglycerin in cardiac low‐output states following valve replacement
Authors: Zwölfer Werner , Keznickl Paul , Dressler Helmut T. , Dieterich Hans A.
Published: February 2009

This prospective, randomized, comparative study was designed to assess the inotropic and vasodilatory effects of the selective phosphosidesterase III inhibitor enoximone compared with standard therapy with epinephrine/nitroglycerin in patients with refractory low output states following cardiac valve replacement. Enoximone possesses inotropic and vasodilatory properties and has proven to be of beneficial effect in patients suffering from severely impaired myocardial function. Six patients in each group received either enoximone bolus‐infusion of 0.5 mg/kg over 10 min followed by an infusion of 5 m̈g/kg/min up to 20 m̈g/kg/min or epinephrine and nitroglycerin infusion of 0.05 and 0.5 m̈g/kg/min, respectively, for 4 hours postoperatively. Hemodynamic effects of enoximone and the combination of epinephrine/nitroglycerin were compared. Both treatments led to positive inotropy with a simultaneous decrease in filling pressures and vascular resistances. The results indicate that enoximone in low‐output states following cardiac valve replacement was at least equally effective in comparison with standard therapy with epinephrine and nitrolycerin.
Right pulmonary artery occlusion secondary to a dissecting aortic aneurysm
Authors: Rau Aruna N. , Glass Mary N. , Waller Bruce F. , Fraiz Joseph , Shaar Carl J.
Published: February 2009

This report describes a case of right pulmonary artery obstruction caused by a dissecting aneurysm of the thoracic aorta. Initial ventilation‐perfusion (V/Q) scan revealed no perfusion to the right lung. Lack of right lung perfusion plus other clinical abnormalities led to an initial diagnosis of massive embolism in the right lung. Bilateral pulmonary arteriography of the thoracic and abdominal aorta revealed extrinsic compression of the right pulmonary artery near its origin and the suggestion of an ascending aortic dissection. Subsequent ascending aortography and computed tomography (CT) confirmed a dissection of the ascending aorta. Aortography in the true lumen of the aorta revealed trivial aortic insufficiency. These diagnostic procedures confirmed the presence of an acute dissecting aneurysm of the ascending aorta that caused compression of the right pulmonary artery. The finding of a massive unilateral segmental defect with normal ventilation upon lung scanning does not always ensure a diagnosis of acute pulmonary embolus. Patient presentation with massive unilateral perfusion defect merits further evaluation with pulmonary arteriography.
Cardiac rehabilitation and secondary prevention after a myocardial event
Authors: Cundey Paul E. , Frank Martin J.
Published: February 2009

In the current era, cardiac rehabilitation after a myocardial event involves physical training in conjunction with optimizing the use of medications to control myocardial ischemia and prevent cardiac complications. It is also the time to identify and treat concomitant psychiatric problems and to develop an individualized program in secondary risk factor modification through counseling, behavior modification, nutritional counseling, and a properly selected drug program. This review attempts to deal with the above matters pragmatically.
Normal left main coronary artery diameter can be predicted from diameters of its branch vessels
Authors: Laslett Lawrence
Published: February 2009

An uncommon though vexing problem exists when the left main coronary artery appears subjectively to be diffusely stenotic relative to its branch vessels, but the severity of such stenosis cannot be determined because of the lack of a normal reference. To overcome this problem, 20 coronary angiograms demonstrating no evidence of disease were quantitatively analyzed to determine the normal ratio of left main diameter to the sum of the diameters of its immediate branches. For bifurcating left mains, the mean ratio of diameter of left main to sum of diameters of its two immediate branches was 0.65 ± 0.04; for trifurcating left mains, the mean ratio of diameter of left main to sum of diameters of its three immediate branches was 0.56 ± 0.02. Thus, it appears feasible and practical to predict the normal diameter of the left main from the measured diameters of its immediate branches.
Hemodynamic response to hyperventilation test in healthy volunteers
Authors: Alexopoulos Dimitrios , Christodoulou John , Toulgaridis Theodoros , Sitafidis George , Klinaki Anna , Vagenakis Apostolos G.
Published: February 2009

Hyperventilation is well known to affect the electrocardiogram (ECG) in subjects without heart disease and produce spasm in patients with variant angina. The autonomic nervous system is thought to play a significant role in these effects. However, the normal hemodynamic response to hyperventilation is not well defined. We subjected 369 healthy volunteers (200 men, 169 women) to prolonged hyperventilation (30 respirations for 5 min and 10 min recovery) under continuous ECG monitoring and to exercise testing. Heart rate (HR), systolic and diastolic blood pressures (SBP, DBP) and rate‐pressure product were recorded. Hyperventilation resulted in an immediate (within the first min), significant increase in HR by 27.4%, a further small increase at min 2 of hyperventilation, and a subsequent small decrease in HR at mins 3‐5. An immediate drop of HR by 20.1% was observed with discontinuation of hyperventilation. Apart from a slightly higher HR increase in men, a similar pattern of HR changes was found in both genders. On multivariate analysis, younger age, absence of smoking, and male gender were associated with a higher HR increase with hyperventilation (p < 0.0001, p < 0.0001, and p < 0.001, respectively). SBP and DBP increased with hyperventilation, with their highest value at min 5 of hyperventilation and a subsequent drop to baseline levels. Age and gender did not affect the degree and pattern of BP changes. Absence of smoking and the presence of hypertension were associated with a higher SBP with hyperventilation (p < 0.003 and p < 0.007). The rate‐pressure product increased by 43.6% with hyperventilation, a change that was only 19.1% of the respective rate‐pressure product observed with exercise. Hyperventilation results in significant HR and BP increases, changes that are influenced by age, gender, smoking, and hypertension. Our study could serve as a standard for comparison of the hyperventilation effects in different disease states.
The predictive value of the electrocardiographic pattern of acute q‐wave myocardial infarction for recurrent ischemia
Authors: Benjaminov Fabiana Sclarovsky , Sclarovsky Samuel , Birnbaum Yochai
Published: February 2009

Atotal of 140 consecutive patients with acute Q‐wave myocardial infarction was evaluated to assess the relationship between different electrocardiographic patterns of evolution and the incidence of recurrent ischemia within 10 days of infarction. Patients were allocated to three groups according to the electrocardiogram at 12 h after admission: Group A: ST elevation of < 2 mm and negative T waves (75 patients); Group B: ST elevation of > 2 mm and negative T waves (35 patients); Group C: ST elevation of > 2 mm and positive T waves (30 patients). Patients in Group C had more anterior wall infarctions (82%) than Group A (40%) or Group B (58%) (p = 0.0001). Peak creatine kinase levels were lower in Group A (782 ± 115 IU) than in Groups B (1415 ± 257 IU) and C (1501 ± 287 IU) (p<0.0001). The occurrence of post‐infarction recurrent ischemia was more frequent in Group A (79.2%) than in Groups B (33.3%) and C (14.8%) (p<0.0001). Patients in Group A had relatively smaller infarctions and a higher incidence of recurrent ischemia, whereas patients in Group C had larger infarctions and a lower incidence of recurrent ischemia. The electrocardiographic pattern 12 h after admission for acute myocardial infarction is helpful in identifying a subgroup at high risk of recurrent ischemia.
This section edited by Bruce Waller, M.D. Usefulness of the 12‐lead electrocardiogram in detection of myocardial infarction: Electrocardiographic‐anatomic correlations—Part I
Authors: Parker Alton B. , Waller Bruce F. , Gering Lawrence E.
Published: February 2009

This two‐part review evaluates a 56‐year period (1938–1994) of electrocardiographic‐necropsy correlation studies. Part I focuses on definitions of infarct location and evaluates anterior infarctions. Part II will focus on lateral and posterior infarcts.
Importance of delaying balloon angioplasty in patients with unstable angina pectoris
Authors: Rozenman Youseph , Gilon Dan , Zeilingher Julian , Sapoznikov Dan , Lotan Chaim , Mosseri Morris , Teddy Weiss A. , Hasin Yonathan , Gotsman Mervyn S.
Published: February 2009

Angioplasty in patients with unstable coronary artery disease is associated with higher complication rates compared with patients with stable disease. In this report we describe our results from a group of patients with unstable disease (unstable angina pectoris and postmyocardial infarction) where a strategy of delaying angioplasty for >5 days after admission was undertaken. Included are 2069 consecutive patients: 1197 treated for stable angina pectoris and 872 treated during admission for unstable angina or myocardial infarction. There was no difference between the two groups in angioplasty success (92.1% stable, 92.3% unstable), failure to dilate without complication (6.4% stable, 6.1 % unstable), or in the rate of major complications: death (0.5% stable, 1.1% unstable), Q‐wave myocardial infarction (0.9% stable, 1.1% unstable), and emergency coronary artery bypass (0.6% stable, 0.3% unstable). The duration of hospitalization following angioplasty was longer in the unstable group (5.6 ± 8.1 days vs. 4.2 ± 4.1 days; p < 0.001) because of longer duration of hep‐arin infusion. There was no difference between groups in minor complications such as groin hematoma and pseudoa‐neurysm, renal failure, or infections. It was concluded that delaying angioplasty in unstable patients for > 5 days after admission is a safe and effective therapeutic strategy for this group of patients. The need for prolonged heparin infusion after angioplasty is increased in unstable patients and thus the duration of hospitalization after the procedure is longer.
Cardiovascular and hormonal responses to a meal in hypertrophic cardiomyopathy: A comparison of patients with and without postprandial exacerbation of symptoms
Authors: Gilligan David M. , Marsonis Antonios , Joshi Jayshree , Bloom Stephen R. , Oakley Celia M. , Nihoyannopoulos Petros , Ghatei Mohammad A.
Published: February 2009

Some patients with hypertrophic cardiomyopathy experience postprandial exacerbation of symptoms. The aim of this study was to determine whether the hemodynamic and/or hormonal responses to a meal differ between patients with and without postprandial symptoms. Ten hypertrophic cardiomyopathy patients with postprandial symptoms, 10 patients without postprandial symptoms, and 10 normal subjects ate a 740 Kcal meal, following which heart rate, blood pressure, and echocardiographic and gastrointestinal hormone changes were compared among the three groups. Heart rate increased (p<0.001) and diastolic blood pressure fell (p < 0.001) to a similar degree in the three groups. Left ventricular outflow tract velocity increased (p< 0.01) and some patients had substantial increases in outflow tract pressure gradient; however, this was independent of the presence or absence of postprandial symptoms. The atrial contribution to filling increased in normal subjects and in both groups of hypertrophic cardiomyopathy patients. There was no significant difference in the gastrointestinal hormone changes in the three groups. In summary, there is no evidence for a distinctive hemodynamic or hormonal response to food in hypertrophic cardiomyopathy patients with postprandial symptoms. These symptoms more likely reflect differences in underlying cardiac disease characteristics and severity.
Angioplasty balloon compliance: Can in vivo size be predicted from in vitro pressure profile measurements?
Authors: More Ranjit S. , Brack Michael J. , Gershlick Anthony H.
Published: February 2009

Background and hypothesis: This study was undertaken to determine whether the behavior of angioplasty balloons within coronary arteries may differ from that anticipated from data provided by the manufacturers. In particular, the in vitro pressure‐diameter profiles may not truly represent in vivo sizes.

Methods: Thus, we assessed the degree of correlation of in vitro with in vivo measurements obtained during routine angioplasty practice. In vivo size of 2.5 mm compliant (n = 8) and 3 mm semicompliant (n = 8) balloons was assessed using quantitative angiography for first, second, and third inflations.

Results: In vivo size was less than expected from in vitro measurements. In general balloon diameter increased with inflation pressures up to 8 atmospheres, and some degree of elastic recoil was evident with both balloon types after the last inflation.

Conclusion: In vivo balloon size may not be accurately predicted from manufacturers' published data. Size is more likely to be affected by factors such as lesion characteristics and elasticity of the vessel wall than by balloon material compliance characteristics.
Pacing therapy for atrial tachyarrhythmias
Authors: Zhu Dennis Wei‐Xi , Spencer William H.
Published: February 2009

The use of pacing techniques for the treatment of atrial tachyarrhythmias has been advocated for more than 30 years. Although it has played a beneficial role in the management of paroxysmal supraventricular tachycardia (PSVT) in drug‐refractory patients, tachycardia acceleration and development of atrial fibrillation has been the major drawback. With the availability of radiofrequency catheter ablation therapy, the use of implantable antitachycardia devices for PSVT is currently negligible. From retrospective and small control studies it has been shown that atrial or dual‐chamber pacing in patients with sick sinus syndrome has been associated with a lower incidence of paroxysmal atrial flutter or fibrillation than in those who received a ventricular pacemaker. Furthermore, recent studies have reported the potential benefit of reducing frequency of paroxysmal atrial flutter and fibrillation with multisite atrial pacing. As a result, there is a resurgence of research interest in antitachycardia pacing for prevention of atrial tachyarrhythmias. This paper briefly describes the basic aspects of antitachycardia pacing, reviews the data on the use of implantable antitachycardia devices for PSVT and the selection of patients, and assesses the current status of research on atrial pacing for prevention of paroxysmal atrial flutter and fibrillation.
Factors associated with the release of cardiac troponin T following percutaneous transluminal coronary angioplasty
Authors: Abbas Syed A. , Glazier James J. , Pears ALL Lisa A. , Waters David D. , Mckay Raymond G. , Wu Alan H. B. , Green Sol F. , Dupont Charles
Published: February 2009

Background: Recent studies have suggested that immunoassay of cardiac troponin T (cTnT) provides a more sensitive measurement of myocardial necrosis than creatine kinase MB (CK‐MB) mass concentration.

Hypothesis: The purpose of this study was to compare the release of cTnT and CK‐MB isoenzyme in patients undergoing percutaneous coronary angioplasty, and to investigate the clinical, procedural, and angiographic correlates of abnormal elevations of both of these markers.

Methods: Total creatine kinase (total CK), CK‐MB, and cTnT levels were measured immediately before and 12 h following intervention in 110 patients, including 100 consecutive patients undergoing coronary angioplasty and 10 control patients undergoing diagnostic cardiac catheterization. All patients had normal levels of all three markers at baseline. A postintervention total CK level >225 U/l, an increase in CK‐MB >5.0 ng/ml, and/or an increase in cTnT >0.04 ng/ml were considered indicative of myocardial injury.

Results: Coronary angioplasty was successfully performed in all 100 patients without emergency bypass surgery or death, although six patients required emergent placement of an intra‐coronary stent for threatened closure. Eight patients demonstrated an abnormal increase in total CK, including six who were undergoing primary angioplasty for an acute myocardial infarction. One of these patients sustained a Q‐wave infarction. Post angioplasty, 18 patients had elevations of both CK‐MB and cTnT, 23 had elevations of only cTnT, and the remaining 59 patients had elevations of neither. All patients with CK‐MB elevation also had cTnT elevation. Neither serologic marker increased in the diagnostic catheterization control patients. In comparison with patients without postintervention cTnT rise, patients with abnormal cTnT levels had a higher incidence of complex lesion morphology (p<0.01) and intra‐coronary thrombus (p ≤0.0001) prior to coronary angioplasty, and a higher incidence of coronary dissection (p≤0.01), abrupt closure (p≤0.05), and side‐branch occlusion (p≤0.01) during angioplasty. In patients with elevation of both cTnT and CK‐MB, postintervention CK‐MB levels were 12‐fold higher and cTnT levels were 21‐fold higher than in patients with isolated elevation of only cTnT (p<0.01).

Conclusions: These data indicate that >40% of patients undergoing coronary angioplasty have evidence of minor degrees of myocardial damage, as evidenced by cTnT release. High‐risk coronary lesions and both minor and major complications of angioplasty are associated with cTnT release. cTnT appears to be a more sensitive marker of myocardial injury than CK‐MB under these circumstances. In comparison with isolated cTnT rise, elevation of both CK‐MB and cTnT may be indicative of greater levels of myocardial injury.
The appearance of gallop rhythm after exercise stress testing
Authors: Tavel Morton E.
Published: February 2009

Background and hypothesis: Although it is generally assumed that the appearance of an early diastolic gallop, or third heart sound, appearing immediately after exercise during treadmill stress testing, indicates the presence of serious myocardial disease, no systematically collected data are available to test this hypothesis.

Methods: The author performed auscultation on 3,679 patients undergoing routine treadmill testing together with thallium‐201 perfusion scans. Exercise‐induced diastolic sounds were related to the available clinical information and electrocardiographic and nuclear test results. These findings were compared with those of 665 randomly selected patients undergoing stress testing in whom such sounds were absent.

Results: A total of 165 patients had audible third heart sounds (Group 1). In comparison with those patients lacking such sounds (Group 2), there was a considerably greater prevalence of myocardial scarring (68.5 vs. 26.9%), abnormal lung uptake of thallium (40 vs. 12.8%), diabetes mellitus (20.6 vs. 6.2%), and left bundle‐branch block on the resting electrocardiogram (ECG) (15.1 vs. 1.2%). In addition, 65 patients (39.3%) had dilatation of the left ventricle after exercise;31 (18.8%) of these were also dilated at rest, but only 2 (1.2%) had a drop in blood pressure during stress. In those individuals also subjected to nuclear ventriculography, the average resting ejection fraction was 35%. Estimated exercise capacity was generally reduced in Group 1 (average peak of 6.6 METs), but 29 (17.6%) exceeded 9 METs. Sensitivity and specificity of electrocardiographic ST depression were relatively poor in the detection of perfusion defects within this group (36 and 62%, respectively). Of the 39 patients in Group 1 with a normal resting ECG, 19 (48.7%) had scar (usually posterior or lateral) on nuclear scans. In an additional 10 of this group, nuclear evidence of ischemia (often extensive) was found.

Conclusions: An early or mid‐diastolic gallop sound developing after exercise virtually always signifies myocardial disease with reduced myocardial function. Common associated findings are prior infarction (with or without associated ischemia), diabetes, and left bundle‐branch block. When found in the presence of a normal resting ECG, this sound commonly signals the presence of an occult left ventricular scar and, less commonly, extensive myocardial ischemia. In those patients manifesting such sounds, electrocardiographic ST changes in response to exercise appear limited in the detection of coronary ischemia.
Chylothorax following median sternotomy
Authors: Zaidenstein R. , Cohen N. , Dishi V. , Alon I. , Golik A. , Modai D.
Published: February 2009

Reports of chylothorax (CT) following median sternotomy are rare, amounting so far to 16 cases in the English literature, of which 6 were cases of postcoronary artery bypass grafting (CABG). This report deals with an additional case of a 70‐year‐old woman who developed left pleural chylous effusion following CABG. It is suggested that the incidence of this type of pleural effusion is considerably greater than the few cases hitherto reported. Moreover, as CT may produce serious pulmonary and/or pleural functional impairment, it is proposed that a diagnostic tap be performed more often in cases of post CABG pleural effusion and that preventive drainage be instituted when CT is diagnosed.
Heart transplantation—An update
Authors: Blum Arnon , Aravot Dan
Published: February 2009

Cardiologists caring for heart transplant recipients must be familiar with the pharmacology, drug interactions, and drug toxicity of those agents used extensively in clinical practice (cyclosporine, prednisone, azathioprine, polyclonal and monoclonal anti‐T‐cell agents) and the newer treatments [methotrexate, FK‐506, rapamycin, mycopheno‐late mofetil (RS61443), deoxyspergualin, anti‐CD4 monoclonal antibodies, total lymphoid irradiation, and photophoresis]. Another important aspect of medical follow‐up is the detection, differential diagnosis, and treatment of allograft dysfunction. Hemodynamic abnormalities that occur as a result of rejection or a direct drug effect must be differentiated from physiologic changes. Cardiac allograft vasculopathy is the primary impediment to the long‐term survival of heart transplant recipients. Immunopathogenesis, prevention, early detection, and treatment of allograft vasculopathy should be the major focus of heart transplantation research.
Abnormal signal‐averaged electrocardiograms in patients with incomplete right bundle‐branch block
Authors: Manolis Antonis S. , Chiladakis John A. , Malakos John S. , Vassilikos Vassilis , Maounis Themos , Cokkinos Dennis V.
Published: February 2009

Background and hypothesis: A hypothesis was formulated that regional delayed activation of the right ventricle, as seen in incomplete right bundle‐branch (IRBBB) aberrancy, may simulate late potential activity and may be responsible for abnormal signal‐averaged electrocardiograms (SAECGs). No previous studies have specifically addressed this issue in this particular group of patients (with IRBBB). Therefore, the aim of the present study was to investigate the incidence of abnormal SAECGs in patients with IRBBB. If this were confirmed, our purpose would further be to investigate ways of reducing the false positive results.

Methods: The study group included 53 patients (28 men and 25 women), aged 53 ± 13 years, with no history of previous myocardial infarction or ventricular tachycardia and who had an electrocardiogram (ECG) showing IRBBB. An SAECG was also performed in a control group of 19 age‐matched individuals with a normal ECG. Time domain analysis was performed using a band pass filter of 40–250 Hz. The following parameters were considered normal: filtered QRS duration (QRSD) < 114 ms, root mean square of the voltage of the last 40 ms of the QRS complex (RMS) > 20 μV, and the duration of the low amplitude signal (< 40 μV) at the terminal portion of the QRS (LAS) < 38 ms. An SAECG was considered abnormal if any two of these criteria were abnormal.

Results: The mean values of the SAECG parameters were: QRSD 101 ± 11 ms, RMS 32 ± 20 μV, LAS 32 ± 12 ms, and noise 0.29 ± 0.13 μV. Abnormal SAECGs with at least two criteria satisfied were present in 16 of 53 (30%) patients compared with 0 (0%) of 19 individuals in the control group (p = 0.02). Abnormal values included the combination of RMS and LAS in 12 patients and all three parameters in 4 patients. However, if the definition of late potentials were limited to the combination of abnormal QRSD and either RMS or LAS values, the incidence of false positive results (4 patients) (7.5%) would be significantly decreased (p = 0.007). At 21 months of follow‐up, no arrhythmic events occurred.

Conclusions: Delayed terminal conduction observed in IRBBB may cause a high incidence of false positive late potentials on SAECGs. Based on this study, we propose that this can be largely remedied if the optimal criteria for the presence of late potentials in patients with IRBBB always include the combination of QRSD and either RMS or LAS.
Coronary artery and saphenous vein graft remodeling: A review of histologic findings after various interventional procedures—part V
Authors: Waller Bruce F. , Orr Charles M. , Van Tassel James , Peters Thomas , Fry Edward , Hermiller James , Grider Larry D.
Published: February 2009

Catheter balloon angioplasty is a well accepted form of nonsurgical treatment of acutely and chronically obstructed coronary artery vessels. It is also the centerpiece for various new intervention techniques. Their morphologic effect on the site of obstruction has been termed “remodeling.” Part V of this six‐part series focuses on remodeling effects of balloon angioplasty on obstructed young (≤ 1 year) and old (> 1 year) saphenous vein bypass grafts.