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T Meinertz

Publications and source records attributed to T Meinertz.

At least 19 recordsLinked to original sources
PubMed1992

Percutaneous mitral balloon valvuloplasty--a comparative evaluation of two transatrial techniques.

The efficacy and safety of two different percutaneous transfemoral mitral balloon valvuloplasty procedures were evaluated in 45 patients. A double-balloon technique with Mansfield balloons was applied in the first 22 patients (group A), and an Inoue single-balloon technique was used in the subsequent 23 patients (group B). Mean diastolic gradient decreased from 17 +/- 7 mm Hg to 8 +/- 3 mm Hg (p < 0.001) in group A and from 13 +/- 4 mm Hg to 8 +/- 3 mm Hg (p < 0.001) in group B. The mitral orifice area increased from 1.1 +/- 0.3 cm2 to 2.2 +/- 0.8 cm2 (p < 0.001) in group A and from 1.2 +/- 0.4 cm2 to 1.7 +/- 0.7 cm2 (p < 0.001) in group B. The length of the total procedure and the total fluoroscopy time were considerably shorter in group B (86 +/- 24 minutes and 18 +/- 7 minutes) compared with group A (128 +/- 38 minutes and 35 +/- 14 minutes; p < 0.001). Mitral regurgitation (grade 3/4) was observed after the procedure in two patients in group A but in nine patients in group B. Cardiac tamponade occurred in two patients in group A, but no major complications were seen in group B. The Inoue single-balloon technique seemed to be safe, easier to perform, and equally effective.

Adult↗
PubMed1992

Effects of amiodarone versus quinidine and verapamil in patients with chronic atrial fibrillation: results of a comparative study and a 2-year follow-up.

Rapid, reliable and safe reestablishment of sinus rhythm is the major aim of pharmacologic treatment in patients with chronic atrial fibrillation. The mainstay of therapy in this arrhythmia has been quinidine. More recently, amiodarone was shown in non-comparative studies to be superior to class IA agents under certain conditions. In 40 patients with atrial fibrillation persisting for 4 weeks up to 2 years, the efficacy and safety of either quinidine and verapamil (days 1 to 3, quinidine 1,500 mg/day; days 4 to 6, quinidine 1,500 mg + verapamil 240 mg/day) or amiodarone therapy (days 1 to 3, amiodarone 1,200 mg/day intravenously; days 4 to 14, amiodarone 800 mg/day orally) were randomly examined. Responders continued on their effective medication for 3 months. Thereafter, all patients were treated with a fixed regimen of quinidine (480 mg/day) plus verapamil (240 mg/day) for up to 2 years. During atrial fibrillation, quinidine reduced mean ventricular cycle length by 40 ms (-5%), quinidine and verapamil increased mean cycle length by 57 ms (8%) and amiodarone by 192 ms (28%, p less than 0.01). In addition, quinidine and verapamil had a characteristic "rate-smoothing" effect on atrioventricular conduction during atrial fibrillation. The rhythm was converted to sinus rhythm after quinidine in 5 (25%) of 20 patients and after the combination of quinidine and verapamil in 11 (55%) of 20 patients. Amiodarone restored sinus rhythm in 12 (60%) of 20 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Amiodarone↗
PubMed1992

Prevalence of circadian variations and spontaneous variability of cardiac disorders and ECG changes suggestive of myocardial ischemia in systemic arterial hypertension.

BACKGROUND: Systemic hypertension is a well-known risk factor for coronary artery disease and sudden cardiac death. Recent interest focused on the presence of malignant ventricular arrhythmias (VA) and myocardial ischemia in hypertensive patients and provided a potential link for fatal tachyarrhythmic events. METHODS AND RESULTS: We studied 150 untreated normokalemic hypertensive patients (56 +/- 9 years; 56 women and 94 men) without manifest coronary artery disease to determine prevalence, severity, and interaction of VA and significant ST segment changes induced by daily activities. One third of the patients were randomized to 4 weeks of placebo and restudied for spontaneous variability of the two parameters. All patients were included in a 3-year follow-up study. VA were observed in 129 of 150 hypertensive patients (86%) and peaked in the early morning and late afternoon. Twenty-two patients (15%) had ventricular pairs, and 20 patients (13%) had nonsustained ventricular tachycardia. Transient ST segment depression observed in 47 patients (33%; mean incidence, 2.7 +/- 0.8 episodes/24 hr) showed a characteristic circadian variation similar to VA and were asymptomatic in 93% of the episodes. At the time of transient ST segment depression, VA increased 4.6 times (p less than 0.01). After 4 weeks of placebo, marked variations in the incidence of VA (VA suppression rate -100%, or increase greater than 400%) were observed in 29% of the patients, and in 60% of all patients repetitive VA were present in only one of the two Holter recordings. Day-and-night variations of VA and transient ST segment changes were highly reproducible during the placebo period. After 3 years of follow-up, eight of 146 patients (5%) had suffered myocardial infarction, and five patients had died from cardiac events (three patients died from sudden cardiac death). Logistic regression analysis revealed left ventricular hypertrophy (relative risk, 6.1; p less than 0.01) and transient ST segment abnormalities during daily activities (relative risk, 4.4; p less than 0.05) to be of independent prognostic significance to predict cardiac events during follow-up instead of repetitive VA (relative risk, 1.3; NS). CONCLUSIONS: VA associated with a high spontaneous variability and predominantly asymptomatic transient ST segment changes are common in hypertensives; the interaction of both risk factors may provide an important link for fatal VA. Antiarrhythmic therapy is not to be recommended in the majority of patients. Presence of left ventricular hypertrophy and transient ST segment changes were the most powerful predictors of cardiac events during the follow-up.

Adult↗
PubMed1992

Clinical implications of new insights into mechanism of antiarrhythmic drug action.

A classification system of antiarrhythmic drugs should help the clinician to select the optimal antiarrhythmic drug for a particular arrhythmia in an individual patient. This goal cannot be achieved by the Vaughan Williams classification system. Other important goals of this classification system were to provide the clinician with some information about proarrhythmic effects and about the possibility of combining particular antiarrhythmic agents. To date, a subdivision of class III antiarrhythmic agents has not been accomplished.

Animals↗
PubMed1992

Efficacy of intravenously administered amiodarone for short-term control of serious arrhythmias.

Intravenously administered amiodarone exerts substantial antiarrhythmic activity that is based on several different electrophysiologic mechanisms. Of these, the most important consists of an antitachycardic effect together with a significant prolongation of repolarization. The acute intravenous administration of amiodarone has been found to be effective in supraventricular and ventricular tachyarrhythmias resistant to conventional antiarrhythmic agents. Because amiodarone is free of detrimental hemodynamic effects in the majority of patients, intravenous administration of this compound seems to be particularly suitable in patients with serious arrhythmias in the setting of compromised left ventricular function.

Action Potentials↗
PubMed1992

Exercise-induced symptomatic and asymptomatic myocardial ischemia in patients with severe coronary artery disease: focus on the efficacy and safety of gallopamil.

Symptomatic and asymptomatic episodes of transient myocardial ischemia are well-known risk factors in patients with coronary artery disease. In a single-blind, randomized, and placebo-controlled study, the efficacy and safety of gallopamil was studied during a 1-week treatment period in 25 patients with high-grade coronary artery stenosis and frequent, exercise-induced episodes of myocardial ischemia. Eighteen patients were men, and seven patients were women; the mean age +/- SD was 59 +/- 7 years. After a 1-week run-in period (days 1-7), all patients were treated with gallopamil 50 mg t.i.d. (days 8-14) and placebo t.i.d. (days 15-21) or vice versa. Twenty-four-hour Holter monitoring, exercise testing, and adverse effects were controlled at days 7, 14, and 21. During the run-in period, all patients suffered a mean of 5.9 +/- 2.9 episodes of transient myocardial ischemia, mean ischemic duration was 38 +/- 29 min/day. Gallopamil increased exercise tolerance from 7.9 to 9.8 min (+24%, p < 0.05) and resulted in reduction of the weekly usage of short-acting nitrates by 45% compared to placebo. During 24-h Holter monitoring, mean heart rate at the onset of ST-segment depression increased from 106 to 118 beats/min (p < 0.05). The frequency of daily ischemic episodes was reduced after gallopamil administration from 6.1 to 3.9 episodes/day (-37%, p < 0.05), the total ischemic burden decreased for symptomatic episodes by -54% (p < 0.05) and for asymptomatic episodes by 29% (p < 0.05). Gallopamil modified the circadian distribution of ischemic episodes by modifying the morning peak of transient myocardial ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

[Clinical evaluation of new anti-arrhythmia drugs after the CAST (Cardiac Arrhythmia Suppression Trial) study].

The results of the Cardiac Arrhythmia Suppression Trial (CAST) are of great importance for the development and clinical evaluation of new antiarrhythmic agents. Today, the development of a new antiarrhythmic drug is only justified, if the benefit risk ratio is superior compared to those agents already available in clinical practice. The primary criterion of therapeutic efficacy is the prevention of tachyarrhythmic sudden cardiac death and/or the prevention of sustained ventricular tachycardia.

Anti-Arrhythmia Agents↗
PubMed1992

[Immunoscintigraphy using 111In-antimyosin-antibodies in the clinical diagnosis of myocarditis].

Thirty patients suspected of having acute myocarditis underwent examination with 111In-labeled antimyosin antibodies. The heart/lung ratio was used for scintigraphic evaluation, with a value of > 1.5 being regarded as positive. The values were correlated with a score based on typical clinical parameters, separating myocarditis into categories "unlikely", "possible" and "highly probable". There was complete correlation in the category "myocarditis highly probable"--with a heart/lung ratio > 1.5 (11 patients)--and in the category of "myocarditis unlikely"--with a heart/lung ratio of < or = 1.5 (5 patients). The category "myocarditis possible" included 2 cases with a scintigraphic vote for the presence of myocarditis and 12 cases against. Immunoscintigraphy with antimyosin antibodies has shown itself to be a valuable non-invasive tool in the investigation of suspected myocarditis.

Acute Disease↗
PubMed1992

[Risk stratification and long-term therapy with amiodarone in patients with idiopathic dilated cardiomyopathy].

Patients with cardiomyopathy are known to suffer from a high prevalence of tachyarrhythmic complications and sudden cardiac death. In a prospective study, 30 patients (25 men, 5 women, mean age: 52 +/- 12 years) with dilated cardiomyopathy underwent 48-h-Holter monitoring and programmed electrical stimulation and, independent from the results of the diagnostic work-up, were then randomized either to amiodarone or to a conventional or no antiarrhythmic therapy. At baseline, frequent ventricular arrhythmias (> 30 ventricular premature beats/h) were observed in 15/30 patients (50%), 13 patients (43%) had repetitive ventricular arrhythmias, additionally. Four patients suffered spontaneous sustained tachyarrhythmias. During programmed electrical stimulation, sustained monomorphic ventricular tachycardia was induced in 3/3 patients with and in 1/25 patients (4%) without a history of sustained tachycardia. Sustained monomorphic ventricular tachycardia was induced with one to two extrastimuli; three extrastimuli only increased the incidence of inducible ventricular fibrillation (8 patients, 28%). During a mean follow-up of 28 +/- 6 months 10/30 patients (33%) died for cardiac reasons (sudden cardiac death: 4/10 patients). Cardiac death was most likely in patients with a left-ventricular ejection fraction < 35% (5/18 patients, 28% versus 1/12 patients with ejection fraction > 35%, 8%) and further increased in the presence of reduced exercise tolerance and frequent and repetitive ventricular arrhythmias (4/7 patients, 57%). In the amiodarone group 4/15 patients died (27%, sudden cardiac death: one patient), while in patients not treated by amiodarone 8/15 patients died (54%; sudden cardiac death: three patients). Amiodarone therapy was well tolerated in all but one patient.

Adult↗
PubMed1992

[Sudden cardiac death: can individual risk be predicted?].

Only 30-40% of all victims of sudden cardiac death could so far be classified as risk patients during their lifetime. Risk factors for sudden death have little predictive value in an asymptomatic population: for example, the typical risk profile for the presence of coronary heart disease and changes in the surface-ECG at rest and especially in the surface-ECG under stress. Usually, the victims of sudden cardiac death among top performance athletes have been suffering from a heart disease of which they knew nothing beforehand: below 40 years of age, mostly from hypertrophic cardiomyopathy; beyond 40, predominantly from coronary heart disease. Among the heart diseases, sudden cardiac death is the cause of death most often in hypertrophic cardiomyopathy, in dilatative cardiomyopathy and in certain types of coronary heart disease. Notwithstanding the employment of fully update cardiological diagnostics the risk patients cannot be identified with reliable precision among those suffering from these diseases. It is only clinically manifest persistent ventricular tachycardia or successful reanimation in case of ventricular fibrillation that will definitely pinpoint the patient as being at risk of sudden cardiac death also in the future.

Cardiomyopathy, Dilated↗
PubMed1979

Pharmacokinetics of azapropazone following single oral and intravenous doses.

The pharmacokinetics of azapropazone (Prolixan) was studied in 7 healthy volunters following single oral and i.v. doses of 600 mg. After i.v. injection plasma concentration declined biexponentially with time. The half-life of the beta-phase was 13.6 +/- 2.6 h (mean +/- SD), the apparent volume of distribution 11.9 +/- 3.5 l, and the total clearance 10.1 +/- 2.1 ml . min-1. Following oral administration peak plasma concentrations occurred between 3 and 6 h and declined with a beta-phase half-life of 14.3 +/- 2.8 h. The binding of azapropazone to plasma proteins was high (ranging from 99.52 to 99.67% at a total plasma concentration of 75 micrograms/ml). The bioavailability of azapropazone when administered as capsules was 83 +/- 19%.

Administration, Oral↗