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Biomedical subjects

K I Lie

Publications and source records attributed to K I Lie.

At least 253 records · Page 14Linked to original sources
PubMed1990

Reocclusion three months after successful thrombolytic treatment of acute myocardial infarction with anisoylated plasminogen streptokinase activating complex.

Thirty consecutive patients with acute myocardial infarction (AMI) were treated with anisoylated plasminogen streptokinase activating complex (APSAC) within 4 hours after onset of symptoms. After 1.5 and 48 hours, patency of the infarct-related vessel and the quantitative degree of residual diameter stenosis were studied by selective coronary angiography. Ventriculograms were made to determine the global left ventricular ejection fraction. Patients showing patency at 48 hours were reevaluated angiographically after 3 months. At 1.5 and 48 hours after APSAC administration patent vessels were demonstrated in 65 and 69% of patients, respectively. Mean residual stenosis decreased significantly from 56 +/- 11% at 1.5 hours to 46 +/- 13% at 48 hours (p less than 0.01). Patients not responding to thrombolytic therapy showed significant deterioration of the left ventricular function during the first 48 hours after AMI. Side effects were minor and mainly associated with invasive procedures. Despite adequate oral anticoagulation, angiographically documented reocclusion at 3 months amounted to 28%. Reocclusion, however, was neither associated with clinically documented reinfarction, nor with a decrease in the left ventricular ejection fraction. Our study shows that APSAC is an effective thrombolytic agent in AMI but that late reocclusion may occur. Oral anticoagulants appear to be less effective in the prevention of reocclusion in the treatment regimen after thrombolysis.

Adult↗
PubMed1990

Digoxin infusion versus bolus injection in rapid atrial fibrillation: relation between serum level and response.

Using available data on time-concentration and time-effect relationships in normal persons the results of infusion of digoxin in various time periods were simulated and compared with administration of digoxin by bolus injections, using a three-compartment pharmacokinetic model to which a separate small side-effect compartment was subsequently added. The validity of the simulations was tested in 11 patients with rapid atrial fibrillation. Serum digoxin concentrations, ventricular rate and side effects were monitored in a double-blind study comparing an infusion of 1.5 mg digoxin over 6 h with administration of three bolus injections of 0.5 mg digoxin 8 h apart. In agreement with the predictions of the model, the maximal fall in ventricular rate was reached after 8-9 h in the infusion group and after 19-20 h in the bolus injection group, without any detectable difference in side effects. There were certain discrepancies between the results of the clinical study and the predictions of the model, e.g. in serum digoxin concentrations, perhaps due to impaired clearance in the patients. However, it is concluded that the tested model is valid in elderly patients with rapid atrial fibrillation.

Adult↗
PubMed1990

The value of class IC antiarrhythmic drugs for acute conversion of paroxysmal atrial fibrillation or flutter to sinus rhythm.

In a single-blind randomized study, the efficacy and safety of intravenous propafenone (2 mg/kg body weight per 10 min) versus flecainide (2 mg/kg per 10 min) were assessed in 50 patients with atrial fibrillation or flutter. Treatment was considered successful if sinus rhythm occurred within 1 h. Conversion to sinus was achieved in 11 (55%) of 20 patients with atrial fibrillation treated with propafenone and in 18 (90%) of 20 with atrial fibrillation treated with flecainide (p less than 0.02). If atrial fibrillation was present less than or equal to 24 h, conversion to sinus rhythm was achieved in 8 (57%) of 14 patients in the propafenone group and 13 (93%) of 14 in the flecainide group (p less than 0.05). Atrial flutter was converted in two (40%) of five patients treated with propafenone and in one (20%) of five with flecainide (p = NS). Mean time to conversion was 16 +/- 10 min in the propafenone group versus 18 +/- 13 min in the flecainide group (p = NS). QRS lengthening (83 +/- 15 to 99 +/- 20 ms) was observed only in the patients treated with flecainide (p less than 0.001). Patients successfully treated with propafenone showed significantly higher plasma levels than those whose arrhythmia did not convert to sinus rhythm. Transient adverse effects were more frequent in the flecainide group (40%) than in the propafenone group (8%) (p less than 0.01). In conclusion, at a dose of 2 mg/kg in 10 min, flecainide is more effective than propafenone for conversion of paroxysmal atrial fibrillation to sinus rhythm. However, considering the propafenone plasma levels and very few adverse effects, the dose or infusion rate, or both, used in the propafenone group may not have been sufficient to achieve an optimal effect. Neither drug seems very effective in patients with atrial flutter.

Atrial Fibrillation↗
PubMed1990

Patency of arm vein grafts used in aorto-coronary bypass surgery.

Arm veins have been used in myocardial revascularisation procedures as a last resort bypass conduit because of their associated low patency. Nevertheless, leg veins and mammary arteries, which are the most commonly used, are sometimes not sufficient, leaving little choice as to the bypass conduit. To assess the properties of arm veins in bypass surgery, we compared a group of 28 patients that underwent an arm vein graft coronary bypass procedure with a matched group of patients in which leg veins were used. In 28 patients, 40 arm vein grafts with 77 distal anastomoses were used (mean 1.9 +/- 0.9; range 1-5). A cerebrovascular accident was the cause of the sole death (2%) during the study period. The mean follow-up was 4.6 years (Standard deviation, SD: 1.5 years). More antianginal medication was used in the arm vein group (P = 0.017). Additionally, the percentage of the expected maximal frequency during exercise testing was lower in the arm vein group as compared to the leg vein group. Digital subtraction angiography showed that the patency of the arm vein bypass grafts was 47% (70% confidence limits, CL: 32%-62%) while the patency of the leg vein grafts was 77% (CL: 64%-87%), which was statistically significant (P = 0.051). Comparison of these figures with the few published reports on arm veins used as coronary bypass grafts reveals similar results. We conclude that the arm vein as a coronary bypass graft is only to be used when mammary arteries and leg veins are not available.

Arm↗
PubMed1990

Different results in cardiopulmonary exercise tests after long-term treatment with felodipine and enalapril in patients with congestive heart failure due to ischaemic heart disease.

We evaluated the cardiopulmonary exercise test results before and after long-term (16 weeks) treatment with the dihydropyridine calcium antagonist, felodipine (10 mg b.i.d., n = 9), and the ACE inhibitor, enalapril (10 mg b.i.d., n = 11), in 20 patients with New York Heart Association class III congestive heart failure. There were no significant differences at baseline. After 16 weeks patients in the enalapril group showed a significant increase in exercise duration and VO2max, without changes in arterial pressures and heart rate. In the felodipine group, exercise duration and VO2max did not change significantly, but arterial pressures and heart rate were significantly reduced at all exercise levels. Between group analysis showed a significant reduction in arterial pressures and heart rate in the felodipine group compared with enalapril, but no differences in aerobic capacity and exercise duration. These results demonstrate that felodipine and enalapril have essentially different effects on cardiopulmonary exercise results in patients with congestive heart failure.

Aged↗
PubMed1990

Effects of isradipine on hemodynamic parameters and ventricular tachycardia in healed myocardial infarction.

The calcium-entry blocker isradipine was tested in a closed-chest pig model for chronic myocardial infarction. Ischemia was evoked in anesthetized pigs (25-35 kg) by inflating a catheter balloon in the left anterior descending coronary artery for at least 45 min. Hemodynamic monitoring and signal averaging of X, Y, and Z electrocardiographic leads were performed (150 beats, filtered at 50 Hz). After reperfusion, all animals developed an accelerated idioventricular rhythm and high creatine kinase (CPK) plasma levels. Coronary venous purines and catecholamines increased transiently. Two hours after reperfusion, heart rate was elevated from the initial 87.5 +/- 6.3 to 126 +/- 6.4 beats/min (p less than 0.01) and the pressure-rate product (PRP, an index of oxygen demand) from 9,530 +/- 630 to 11,950 +/- 790 mm Hg/min (p less than 0.05). After 2 weeks, six surviving pigs had a decreased stroke volume (98 +/- 18 versus the initial 124 +/- 14 microliters/kg, p less than 0.05), a prolonged high-frequency signal-averaged QRS duration (81.2 +/- 6.5 versus 65.7 +/- 2.9 ms, initially; p less than 0.05), and ventricular tachycardias (VTs), inducible by programmed electrical stimulation (PES). After the infusion of isradipine (1 microgram/kg/min for 30 min), the cardiac index increased from 92 +/- 14 to 133 +/- 8.7 ml/min.kg (p less than 0.02). Even at a higher heart rate, the PRP dropped from 12,600 +/- 1,900 to 10,560 +/- 1,400 mm Hg/min (p less than 0.05). Sustained monomorphic tachycardias were inducible in five pigs before and in three pigs after isradipine, and no deterioration of the signal-averaged electrocardiogram parameters was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Efficacy and safety of ibopamine in congestive heart failure.

1. Ibopamine is a new orally active inodilator, which is developed for the treatment of congestive heart failure (CHF). We treated 13 patients with moderate to severe CHF already on maximal conventional medication with ibopamine and studied its effects on haemodynamic parameters, exercise capacity, plasma norepinephrine (NE) and ventricular arrhythmias on ambulatory ECG monitoring. 2. Both cardiac and stroke volume index increased significantly after ibopamine (33% and 35% resp.). These changes were accompanied by a fall in systemic vascular resistance without changes in heart rate or blood pressure. During cardiopulmonary exercise testing, both maximal oxygen consumption and exercise time increased. Plasma NE levels were not significantly changed after ibopamine. Using the Morganroth criteria for proarrhythmia on ambulatory ECG monitoring, two patients showed proarrhythmia from ibopamine, which was not clinically relevant, but four patients had a decrease in ventricular arrhythmias. 3. This study suggests that ibopamine elicits favourable effects on haemodynamics and exercise tolerance in patients with CHF. During ibopamine treatment, there appears to be no increase in ventricular arrhythmias.

Adult↗
PubMed1990

Analysis of the morphology of the unipolar endocardial paced evoked response.

In a retrospective study we analyzed the unipolar endocardial evoked response signal (ERS) of 103 patients prior to pacemaker implantation. The objective of this study was to give a complete description of the ERS morphology and to evaluate influences on this morphology of both various electrode characteristics and pacing rate. In addition, spontaneous endocardial signals were studied. The results demonstrate that acute leads had both higher R wave and T wave amplitudes and a faster downslope of the T wave. In the acute leads those with porous titanium carbon coated tips showed a more pronounced T wave. Pacing rate influences the R wave amplitude and the stimulus to T wave interval. Both stimulus to maximum and stimulus to minimum T wave interval show an exponential correlation with the stimulus interval. The interval between maximum and minimum of the T wave and the absolute amplitude of T wave are not influenced by rate. Although there were significant correlations of the spontaneous endocardial signal with the ERS, the predictive value of the spontaneous signal for the ERS morphology is low. Prospective studies will be necessary to confirm the findings in this study.

Aged↗
PubMed1990

Range of atrioventricular conduction disturbances in Lyme borreliosis: a report of four cases and review of other published reports.

Four patients with Lyme borreliosis had atrioventricular conduction disturbances. All four were positive for specific antibodies against Borrelia burgdorferi measured by indirect immunofluorescence tests. Biopsy specimens, which were obtained in three patients, showed band-like infiltrates of plasma cells and lymphocytes in the endocardium. There was diffuse infiltration of the interstitium of the myocardium by lymphocytes, plasma cells, and macrophages. In two patients single fibre necrosis was seen in the myocardium. Biopsy specimens of the heart showed spirochetes in all three patients and serial sections stained by the Bosma-Steiner technique showed that they resembled Borrelia burgdorferi. At follow up one patient had persistent complete atrioventricular block, despite treatment with antibiotics and corticosteroid, and a permanent pacemaker was implanted.

Adult↗
PubMed1990

A systemic non-lytic state and local thrombolytic failure of anistreplase (anisoylated plasminogen streptokinase activator complex, APSAC) in acute myocardial infarction.

The relation between coronary thrombolysis and coagulation variables after administration of anistreplase (anisoylated plasminogen streptokinase activator complex, APSAC) was studied in patients with an acute myocardial infarction. Fifty eight consecutive patients with acute myocardial infarction were given 30 U of anistreplase intravenously within 4 hours of the onset of symptoms. A fall in the plasma concentration fibrinogen to less than 1.0 g/l 90 minutes after administration of anistreplase was considered to reflect a systemic lytic state. Coronary angiography was performed 48 hours after thrombolytic treatment. The overall patency rate was 74% (43/58). Patency rates were significantly different in patients with a systemic lytic (83% (43/52)) and a systemic non-lytic state (0% (0/6)). The absence of a systemic lytic state after anistreplase administration seemed to be highly predictive of the failure of coronary thrombolysis. Coagulation studies showed evidence of inhibition of anistreplase induced fibrinolytic activity which may explain the failure of thrombolytic treatment in patients with evidence of a systemic non-lytic state.

Adult↗
PubMed1990

Safety and efficacy of beta-blockers in the treatment of stable angina pectoris.

In stable exercise-induced angina pectoris, beta-blockers exert their beneficial effects mainly through a reduction in heart rate, blood pressure. and contractility. Additional beneficial effects are an improvement in myocardial oxygen supply through a redistribution of coronary flow, a lengthening of diastole, a facilitation of aerobic metabolism, and a rightward shift of the oxygen-hemoglobin dissociation curve. Cardioselective beta-blockers can be expected to have fewer side effects than the nonselective drugs. Apart from a reduction in anginal attack rate and an improvement in exercise capacity, a reduction in silent ischemia may be desirable when treating patients with stable effort angina, beta-blockers effectively reduce asymptomatic ischemia. Bisoprolol is a new beta1-selective beta-blocker with a clear 24-h duration of action regarding symptoms and improvement of exercise capacity in patients with stable exercise-induced angina pectoris. Bisoprolol 10 mg and atenolol 100 mg are equipotent in achieving these effects.

Adrenergic beta-Antagonists↗
PubMed1990

Bisoprolol pilot studies in myocardial infarction.

The efficacy of beta-blockade after myocardial infarction (MI) has been investigated in a series of studies. When beta-blockers are used during the first hours after the onset of MI, a reduction in infarct size, mortality, and nonfatal reinfarction may occur. Bisoprolol is a highly beta1-selective beta-blocker, without intrinsic sympathomimetic activity (ISA), and with a plasma elimination half-life of 10-12 h, permitting treatment with one daily dose. Because no experience with bisoprolol was available in MI, its safety and efficacy were studied in two open, uncontrolled pilot studies. The first study was a dose-finding study in 37 patients with a 3-day-old MI. Bisoprolol was given intravenously and carefully titrated in steps of 1 mg up to a cumulative maximum dose of 5 mg. Subsequently, the patients received 10 mg of oral bisoprolol once daily (o.d.) until the end of the study. Based on the results of this first pilot study, a second pilot study was performed in which bisoprolol was given within the first 6 h after the onset of MI. Intravenous (i.v.) bisoprolol was titrated in two steps of 2.5 mg each, directly followed by 10 mg of oral bisoprolol o.d. The aim of this study was to investigate the influence of i.v. and subsequent oral bisoprolol on central hemodynamics. The results of these studies demonstrate that i.v. and subsequent oral administration of bisoprolol is well tolerated and indicate that the selected dose regimen is hemodynamically safe.

Administration, Oral↗
PubMed1990

Flecainide: long-term effects in patients with sustained ventricular tachycardia or ventricular fibrillation.

Efficacy of flecainide was investigated in 50 patients with sustained ventricular tachycardia (n = 38) or ventricular fibrillation (n = 12) during a 4-week in-hospital and 1-year follow-up period. Furthermore, the predictive value of programmed electrical stimulation, Holter monitoring, and exercise testing on outcome of long-term treatment was studied. Etiology of the tachyarrhythmia was coronary artery disease in 37 patients and other etiologies in 13 patients. The success rate of flecainide after 1 year, based on intention to treat, was 54%. The success rate during the in-hospital phase was 84% (in six patients flecainide was discontinued because of tachyarrhythmia and in two because of side effects). Calculated after 4 weeks hospitalization, the success rate was 78% for patients with tachyarrhythmias based on coronary artery disease and 55% for patients with tachyarrhythmias based on other etiologies (11 patients showed recurrences and two patients severe side effects). Patients with tachyarrhythmias based on coronary artery disease showed a lower ejection fraction and earlier recurrence than patients with arrhythmias based on other etiologies. Proarrhythmic effects developed in six patients (12%). Electrophysiological evaluation was performed in 28 patients at baseline and after intravenous flecainide. Negative predictive value of the electrophysiological evaluation after intravenous flecainide for patients with inducible tachyarrhythmias at baseline (n = 21) was 40%. For Holter monitoring (n = 24) this value was 86%. Non-ischemia-related induction of tachycardia by exercise was present in two of 30 patients on flecainide; both patients showed recurrence of the tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Efficacy and safety of flecainide acetate in the maintenance of sinus rhythm after electrical cardioversion of chronic atrial fibrillation or atrial flutter.

The efficacy and safety of flecainide were studied in the maintenance of sinus rhythm after electrical cardioversion for chronic atrial fibrillation or atrial flutter. Eighty-one patients were randomized to flecainide treatment or no treatment. Baseline characteristics of both groups were comparable. Compared to previous studies, patients could be classified as difficult-to-treat patients. Multiple regression analysis showed New York Heart Association class I for exercise tolerance (p = 0.0004) and flecainide treatment (p = 0.01) to be the main factors increasing the arrhythmia-free episode. However, Mantel-Cox lifetable analysis did not reveal significant differences between arrhythmia-free survival curves of both treatment groups. In the flecainide-treated group, 9% of patients experienced side effects, mostly related to negative dromotropic effects. The incidence of ventricular proarrhythmia in this group of patients was low. Thus, flecainide may be effective in postponing arrhythmia recurrence, even in difficult-to-treat patients. Caution should be excercised in treating patients with underlying conduction disturbances, sick sinus syndrome or characteristics favoring development of ventricular proarrhythmia.

Adolescent↗
PubMed1989

Cardiac electrophysiologic properties of intravenous isradipine in patients with sick sinus syndrome.

Isradipine is a new dihydrophyridine calcium antagonist with powerful vasodilating properties. Although therapeutic concentrations do not affect myocardial contractility in vivo, in vitro studies have demonstrated a negative chronotropic action with only minor dromotropic influence. In humans with normal sinus and atrioventricular node function, even in the presence of beta-blockade, such a negative chronotropic effect could not be proved. No data are available on the effects of isradipine on a compromised sinus node. Therefore, the effect of intravenous isradipine at 0.3 microgram/kg/minute for 30 minutes was studied in seven patients with the clinical signs of a sick sinus syndrome. Mean arterial blood pressure decreased from 126 +/- 21 to 113 +/- 15 mm Hg (p less than 0.05). Spontaneous sinus cycle length decreased from 969 +/- 22 to 843 +/- 161 msec (p less than 0.05). Changes in sinoatrial conduction time, sinus node recovery time, and corrected sinus node recovery time were not significant. Changes in atrioventricular node function, as reflected by the atrioventricular node functional refractory period, the atrial-His interval, the His-ventricle interval, and Wenckebach point were not significant. Also, effective refractory periods of atrium and ventricle, and QRS duration changed but not significantly. The QT interval decreased (419 +/- 45 to 405 +/- 44 msec; p less than 0.05), and there was a slight (not significant) increase of QTc interval (429 +/- 41 to 443 +/- 37 msec; not significant). It is concluded that isradipine in hemodynamically effective doses has no depressant effect on sinus and atrioventricular node function in patients with sick sinus syndrome.

Adult↗