bluuebunny/crossref_metadata_2025_split huggingface dataset:
The mitral valve mechanism with normal and prolapsed leaflets in the light of a dynamic model
Authors: Bryhn M. , Gåarding L. 
Published: February 2009

AbstractA dynamic model was presented to explain some of the clinical and morphologic findings in primary mitral valve prolapse. In normal cases, the leaflets, chorda tendinae, the annular ring, and the papillary muscles represent a functional entity balanced by the pressure force acting upon the leaflets. When the leaflets are larger, as in primary mitral valve prolapse, a negative interference with this balance is achieved, causing an increased traction on the papillary muscles and a concomitant dilatation of the annular ring.
Magnetic resonance imaging (MRI) in different stages of myocardial infarction using the contrast agent gadolinium‐DTPA
Authors: Eichstaedt H. W. , Felix R. , Dougherty F. C. , Langer M. , Rutsch W. , Schmutzler H. 
Published: February 2009

AbstractWe investigated 26 patients admitted to our catheterization laboratory with a diagnosis of acute myocardial infarction. In each case acute revascularization was unsuccessful, but the diagnosis was confirmed by angiography. In 11 patients with an uncomplicated course of acute myocardial infarction magnetic resonance imaging was carried out within 7 days of the acute event. In three additional cases imaging was performed within 3 weeks, while a remaining 12 patients underwent studies more than 3 weeks after the onset of symptoms. We determined signal intensity at three points within the area of infarction and at three other points in adjacent myocardial tissue. Decreased signal intensity within the area of infarction was present in native scans in 60% of all cases. Application of 0.1 mmol/kg body weight gadolinium‐DTPA was followed by an average 70% increase in signal intensity within zones of acute infarction, as compared to a 20% increase in surrounding myocardial tissue. In cases of subacute and chronic infarction there was no significant signal enhancement after administration of gadolinium‐DTPA. Uptake of gadolinium‐DTPA in the area of acute myocardial infarction may be a positive marker of acute myocardial necrosis, which may be of potential clinical benefit.
Noninvasive findings in patients with hypertrophic and dilative cardiomyopathy: A combined echocardiographic and radionuclide angiographic study
Authors: Bryhn M. , Persson S. 
Published: February 2009

AbstractFifteen patients with hypertrophic (HCM) and 15 with dilative cardiomyopathy (DCM) were examined with radionuclide angiography and M‐mode echocardiography to evaluate the combination of two noninvasive methods for measuring left ventricular performance. The patients with HCM had delayed myocardial relaxation and rapid filling time with preserved peak rate of early ventricular filling. DCM patients, on the contrary, had low values of left ventricular systolic performance and low peak filling rate. Myocardial relaxation and rapid filling time, however, were short, indicating compensatory mechanisms in the failing ventricle improving rapid filling.
Prolonged survival with a thrombotically occluded tricuspid valve prosthesis
Authors: Harjula A. , VENTILATA M. , MATTILA S. 
Published: February 2009

AbstractA 49‐year‐old man who had undergone tricuspid valve replacement with a Bjöork‐Shiley prosthesis in November 1974 was reoperated on in January 1985 due to prosthesis malfunction. The operation revealed a totally occluded prosthetic valve and a paravalvular defect which had served as the channel for atrioventricular blood flow. In retrospect, all evidence indicated that the valve had stuck as early as six months after the primary operation, when the patient had first noticed the loss of audible valve clicks and the reappearance of effort intolerance. Due to the gradual progression of the patient's symptoms and misinterpretation of the significance of absent valve clicks, the correct diagnosis was not made until a follow‐up study 10 years after the first operation when contrast echocardiography showed the absence of both disc movements and transvalvular contrast flow. Our experience indicates that thrombosis of a tricuspid valve prosthesis may present highly insidiously and that the loss of audible valve clicks should be relied on as a sign of prosthesis malfunction.
Recurrence of coronary artery spasm after successful percutaneous transluminal coronary angioplasty
Authors: Takashiba K. , Ebihara H. , Hamada Y. , Hyakuna E. , Matsuda Y. 
Published: February 2009

AbstractA 47‐year‐old man presented with angina, and coronary angiograms showed a significant organic stenosis with spasm in the left anterior descending coronary artery. Percutaneous transluminal coronary angioplasty was successfully performed for the organic lesion in the left anterior descending coronary artery. Symptom of angina due to coronary artery spasm recurred, even without restenosis at the site of successful angioplasty.
Acute myocardial infarction during streptokinase therapy
Authors: Horn E. M. , Amin D. K. , Lew A. S. 
Published: February 2009

AbstractA 45‐year‐old man developed sequential inferolateral and anterior myocardial infarctions within 10 hours of a possible allergic reaction to oral penicillin. The anterior myocardial infarction occurred during apparently successful streptokinase therapy for the initial inferolateral infarction. Subsequent coronary arteriography confirmed a subtotal stenosis of the left circumflex coronary artery and a complete thrombotic occlusion of the left anterior descending artery. This case documents the occurrence of three rare clinical phenomena; first, the occurrence of sequential acute myocardial infarctions in close temporal proximity; second, the occurrence of myocardial infarction during thrombolytic therapy; and third, the association of myocardial infarction with a possible allergic reaction.
Ventricular parasystole and ventricular couplets: A re‐entry within the parasystolic focus?
Authors: Santinelli V. , De Paola M. , Smimmo D. , Turco P. , Condorelli M. 
Published: February 2009

AbstractWe report a 62‐year‐old man with a persistent ventricular rhythm originating in a parasystolic focus associated with frequent ventricular couplets with fixed coupling. Both intravenous (IV) procainamide (l g) and propafenone (70 mg IV) promptly suppressed only the second component of ventricular couplets, suggesting that re‐entry rather than enhanced automaticity was the mechanism of ventricular couplets. On the contrary, the nonresponse of ventricular rhythm and ventricular couplets to verapamil (10 mg IV) suggested that triggered activity should not play a role in the genesis of this ventricular rhythm. The mechanisms of the ventricular couplets (rapidly discharging parasystolic focus vs. re‐entry) are discussed.
Asynergy and left ventricular performance in dilative cardiomyopathy
Authors: Zucchi R. , Barsotti A. , Mariotti R. , Biadi O. , Balbarini A. , Mariani M. 
Published: February 2009

AbstractThe purpose of this work was to evaluate the presence and importance of asynergy in dilative cardiomyopathy. A semiautomatized analysis of left ventriculograms was performed in 18 cases, the morphology of longitudinal and transverse axes time‐length curves was evaluated, and mathematical indices of asynchrony and hypokinesis were defined. Ten normal subjects and 9 patients affected by aortic regurgitation were used as controls. In dilative cardiomyopathy, anomalous (polyphasic) time‐length curves were present in 55% of the cases, while they were absent in aortic regurgitation and in all normal subjects but one. In addition, the asynchrony index was slightly increased and the hypokinesis index significantly increased (28.8$$7.2% vs. 17.8$$7.1%, p<0.001). A negative correlation existed between the asynchrony index and the ejection fraction (r= −0.483, p<0.05) and both the ejection fraction and the maximum normalized velocity of contraction were reduced in the patients with the anomalous curves (29.7$$6.9% vs. 46.0$$11.5%, p<0.01; 1.66$$0.52 s−1 vs. 2.86$$1.33 s−1, p<0.02). It was concluded that asynergy, and especially asynchrony, is frequent in dilative cardiomyopathy and it is strongly associated with a major impairment of overall left ventricular function.
Changes of heart rate and QT interval at high altitude in alpinists: Analysis by holter ambulatory electrocardiogram
Authors: Horii M. , Takasaki I. , Ohtsuka K. , Tsukiyama H. , Takahashi A. , Hatori Y. , Hakuta. T. 
Published: February 2009

AbstractThe purpose of this study is to record continuously electrocardiograms of alpinists during different activities practiced in mountaineering, compare heart rate and QT interval at high altitude with those at sea level, and compare alpinists with nonalpinists. Analysis was attempted on 14 alpinists (9 male, 5 female, ages 26–45) to determine changes in heart rate and QT interval using continuous ambulatory electrocardiograms recorded at sea level and high altitude. Between 1983 and 1984, 9 of 14 alpinists (6 male, 3 female) were subjected to the study at high altitude, that is, at Mt. Kangchenjunga (Himalaya), Mt. Satopanth (Himalaya), and Mt. Jitudake (Butan), 4400 to 7800 m (mean 5710 m). The following were noted: (1) Heart rate at high altitude was significantly higher both in daytime and nighttime. The circadian rhythm of the heart rate disappeared at extremely high altitude in several al alpinists. (2) A high correlation was noted between measured QT interval (QT!m) and RR interval (r=0.81, p=0.005). Nighttime QTm at high altitude was prolonged in comparison with that of daytime so far as the RR interval remained the same. (3) At high altitude, the nighttime corrected QT interval (QTc) was also significantly prolonged in spite of shortened RR interval. The mechanism of QTc prolongation is not clear. Many factors may impact on the QT interval during mountaineering.
Thrombolysis of acute total occlusion of the left main coronary artery and long‐term survival
Authors: Biron Y. , Laurent M. , Bourdonnec C. , Coeurderoy A. , Almange C. , Le Helloco A. 
Published: February 2009

AbstractA young woman was admitted with acute anterior myocardial infarction. Emergency coronary angiography showed a total occlusion of the LMCA. Selective infusion of streptokinase recanalized the left main coronary artery (LMCA), the circumflex artery, and the first diagonal, but not the entire left anterior descending artery (LAD). The right coronary artery was dominant and normal. The left‐sided congestive heart failure was severe; treatment improved the heart failure and the patient was discharged on Day 25. She was readmitted for control 28 months later: she was only moderately disabled and coronary angiography showed the same occlusion of the LAD; result on ejection fraction (right anterior oblique view 30d̀) was not significant, but circumflex artery recanalization probably preserved lateral wall contraction. The presence of a normal dominant right coronary artery seems to be a very important factor in contributing to initial survival.
Effects of propranolol, atenolol, and chlordesmethildiazepam on response to mental stress in patients with recent myocardial infarction
Authors: Mazzuero G. , Galdangelo F. , Zotti A. M. , Bertolotti G. , Tavazzi L. 
Published: February 2009

AbstractStress testing was carried out by two stressors, mental arithmetic and Sacks‐Levy's test in randomized sequence, in64 male patients with a mean age of 51±7 years in NYHA Classes I or II within 3 months after acute myocardial infarction. The stress profile was obtained after drug withdrawal by continuous recording of electrocardiogram, frontal electromyogram, and peripheral skin temperature and conductance. Blood pressure was measured each minute by cuff. The patients were subdivided into 4 groups of 16 each and were studied in an identical fashion aftera48‐h oral treatment with propranolol 120 mg daily, atenolol 100 mg daily, chlordesmethyldiazepam 2 mg daily, or placebo. During stress, signs of myocardial ischemia or pump failure were not observed; minor arrhythmias were recorded. Cardiovascular activation was observed with significant increments (p<0.001)in heart rate, systolic and diastolic blood pressures in all 4 groups for both stressors with a slightly greater effect of mental arithmetic; Sacks' test was more effective on the frontal electromyograph response. Following beta blockade the stress profile of heart rate was significantly lower and flattened. The stress profile of blood pressure was also lower, but the reduction in the increment during stress was not significant. No differences were observed in the effects of the two beta blockers; no significant changes were evident in the stress profile of the noncardiovascular psychophysiologic indexes. Stress profiles were not altered by the benzodiazepine. In conclusion beta‐blocker agents seem to be more useful than anxiolytic drugs in preventing cardiovascular activation induced by mental stress in patients with recent myocardial infarction.
Propafenone versus disopyramide: A double‐blind randomized crossover trial in patients presenting chronic ventricular arrhythmias
Authors: Libersa C. , Caron J. , Pladys A. , Beuscart R. , Kacet S. , Wajman A. , Connell C. , Dupuis B. , Lekieffre J. 
Published: February 2009

AbstractIn vitro and in vivo electrophysiological studies have shown that propafenone could be classified as a class I antiarrhythmic agent. The aim of this study was to investigate the short‐term antiarrhythmic efficacy and safety of propafenone in 10 patients compared to disopyramide in a double‐blind randomized protocol. Included patients suffered from ventricular arrhythmias with at least 60 ventricular premature beats (VPB) per hour refractory to at least two other antiarrhythmic agents. At the end of the control period and of the two treatment periods during which patients received either propafenone (300 mg three times a day) or disopyramide (200 mg three times a day), clinical examination, Holter recordings, electrocardiogram, and clinical laboratory tests were performed. The PR interval and the QRS interval were significantly increased with propafenone, but not with disopyramide. The cQT interval was not significantly changed by either propafenone or disopyramide. Heart rate was decreased with propafenone (p<0.05) with no change in the diurnal/nocturnal circadian ratio variation. Heart rate was significantly decreased with disopyramide only during the day. Five of nine patients in the propafenone group and two of nine patients in the disopyramide group showed a reduction in ventricular premature beats greater than 80%. Total resolution of severe arrhythmias (repetitive events) was seen in 5 of 8 patients with propafenone; 2 of 8 with disopyramide. Adverse events, when they occurred, were mild (visual disturbances, epigastric discomfort, changes in taste perception, transient atrioventricular block with propafenone, and photophobia with disopyramide), and did not require reduction or discontinuation of study drug. Considering these results, propafenone is expected to be an efficient antiarrhythmic drug in the treatment of severe ventricular arrhythmias.
Efficacy and tolerance of tocainide during long‐term treatment of malignant ventricular arrhythmias
Authors: Mohiuddin S. M. , Esterbrooks D. , Mooss A. N. , Dahl J. M. , Hilleman D. E. 
Published: February 2009

AbstractA group of 51 patients with malignant ventricular arrhythmias refractory to standard oral antiarrhythmic agents were treated with oral tocainide. Antiarrhythmic efficacy was defined as total abolition of occurrences of ventricular tachycardia (VT) or ventricular fibrillation (VF) as assessed by hospital admissions for arrhythmias and the occurrence of sudden cardiac death (SCD). Of the 51 patients, 32 (63%) initially tolerated tocainide and were discharged from the hospital. Of the 19 patients not initially responding to tocainide, 6 (12%) had arrhythmia recurrence and 13 (25%) developed intolerable central nervous system or gastrointestinal side effects. Of these 19 short‐term nonresponders, 8 (42%) patients suffered SCD over an average follow‐up of 24 months (annual SCD rate of 21%). Two patients suffered SCD during the first week of tocainide therapy. Discounting the 2 patients with SCD on tocainide therapy, 6 of 17 (35%) patients initially withdrawn from tocainide suffered SCD (annual SCD rate of 18%). Twenty‐four of the 32 short‐term responders did not have arrhythmia recurrence over a mean follow‐up of 38 months resulting in an overall long‐term efficacy of 47% (24/51). Over an average follow‐up of 38 months for these 24 short‐term responders, 12 patients expired from nonarrhythmic causes, 3 patients were withdrawn for non‐drug‐related causes, and 9 patients remain on tocainide therapy. Of the 8 long‐term nonresponders, 3 patients had arrhythmia recurrence and died suddenly while 5 patients developed intolerable side effects. The annual SCD rate in short‐term responders was 3%. Eighteen of the 51 patients (35%) were withdrawn from the study because of adverse effects. We conclude that tocainide is a valuable addition to the limited number of antiarrhythmic agents effective for the management of patients with malignant ventricular arrhythmias. A reduction in SCD rates may be expected in patients who tolerate and respond to tocainide during acute therapy.
Malignant ventricular arrhythmia in the wolff‐parkinson‐white syndrome during amiodarone treatment
Authors: Perticone F. , Cuda G. , Spadea F. , Pintaudi C. , Tropea R. 
Published: February 2009

AbstractThe ventricular rate during rapid atrial rhythms is related in Wolff‐Parkinson‐White (WPW) syndrome to antegrade effective refractory period of the accessory pathways. Among the many antiarrhythmic drugs available, amiodarone is most commonly used for its large therapeutic window and very long half‐life. We report a case of cardiac pre‐excitation syndrome in a young male patient in whom amiodarone therapy (3000 mg/weekly) was instituted to modify the dangerous ventricular response during atrial fibrillation (shortest R‐R interval 190 ms, ventricular rate 210 beats/min). Four months later, starting pharmacological treatment, a new electrophysiological study documented a malignant ventricular arrhythmia: during atrial fibrillation the minimum R‐R interval was 160 ms and the ventricular rate 280 beats/min. Finally, the possible mechanism of paradoxical effect observed in our patient is hypothesized. Amiodarone could favor conduction over the accessory pathways by slowing or blocking conduction into the atrioventricular node and decreasing concealed retrograde conduction into the accessory bypass tract by normally conducted beats.
The Nature of ventricular arrhythmias during ergonovine‐induced vasospastic angina pectoris
Authors: Nakaya Y. , Hiasa Y. , Fujino K. , Aihara T. , Mori H. 
Published: February 2009

AbstractThe peak incidence of ventricular fibrillation in acute myocardial infarction usually occurs during the first hours after the onset. Electrophysiological changes immediately after the onset have been studied in animal models, but are still incompletely understood in humans. For clarification of the characteristic features of ventricular arrhythmias during acute myocardial ischemia, ventricular arrhythmias were studied in 81 patients with vasospastic angina pectoris induced by ergonovine. Ventricular arrhythmias occurred in 45 of these patients, including ventricular tachycardia in 15, and ventricular fibrillation requiring repeated DC defibrillation in two patients. Most ventricular extrasystoles occurred before the ST segment reached maximum elevation, while reperfusion arrhythmias were less common. In many patients the coupling intervals varied, and the configuration was multiform. It is concluded that ventricular arrhythmias occurring during ergonovine‐induced coronary spasm show different characteristics from those occurring during chronic ischemia. As the arrhythmias in this study seem, in some ways, to resemble arrhythmias occurring at the onset of myocardial infarction, the results might provide useful information on ventricular arrhythmias in myocardial ischemia in humans.
Early diastolic time intervals during hypertensive pregnancy
Authors: Spinelli L. , Ferro G. , Talarico G. , Cinquegrana G. , Condorelli M. , Nappi C. , Farace M. J. 
Published: February 2009

AbstractEarly diastolic time intervals have been assessed by means of the echopolycardiographic method in 17 pregnant women who developed hypertension during pregnancy (HP) and in 14 normal pregnant women (N). Systolic time intervals (STI), stroke volume (SV), ejection fraction (EF), and mean velocity of myocardial fiber shortening (VCF) were also evaluated. Recordings were performed in the left lateral decubitus (LLD) and then in the supine decubitus (SD). In LLD, isovolumic relaxation period (IRP) was prolonged in the hypertensive pregnant women compared with normal pregnant women (HP 51±12.5 ms, N 32.4±15 ms p<0.05), whereas time of the mitral valve maximum opening (DE) was not different in the groups. There was no difference in SV, EF, and mean VCF, whereas STI showed only a significant (p<0.05) lengthening of pre‐ejection period (PEP) in HP. When the subjects shifted from the left lateral to the supine decubitus position, left ventricular ejection time index (LVETi) and SV decreased significantly (p<0.05) in both normotensive hypertensive pregnant women. IRP and PEP lengthened significantly (p<0.05) only in normals, whereas they were unchanged in HP. DE time did not vary in either group. In conclusion, hypertension superimposed on pregnancy induces lengthening of IRP, as well as of PEP, and minimizes the effects of the postural changes in preload on the above‐mentioned time intervals.
Arm position as a source of error in blood pressure measurement
Authors: Mariotti G. , Alli C. , Avanzini F. , Canciani C. , Di Tullio M. , Manzini M. , Salmoirago E. , Taioli E. , Zussino A. , Radice M. 
Published: February 2009

AbstractThe present study was designed to assess the value of correct positioning of a patient's arm when measuring blood pressure (BP). A total of 181 subjects were examined, 141 hypertensives on treatment, 25 untreated hypertensives, 15 normotensives. All the subjects underwent three BP measurements after a 5‐min resting period in supine position. Then two BP readings were recorded in standing position with the arm either positioned by the patient's side or supported passively at patient's heart level. Average systolic BP (SBP) in standing position were 144.6±20.2 mmHg with the arm at the side and 136.4±21.1 mmHg with the arm at the heart level (p<0.001); average diastolic pressures were 99.0±12.0 mmHg and 90.2±12.3 mmHg (p<0.001), respectively. A fall in SBP ± 20 mmHg from the supine to the upright position was detected in 18.2% of cases when measurement was performed at heart level; such a reduction was inapparent in two‐thirds of cases when the arm was placed at the patient's body side. Incorrect positioning of a patient's arm during BP measurements in standing position leads to overestimation of BP values and masks the presence of postural hypotension.