Bedside markers of coronary reperfusion.
Explore the source record for details and available documents.
Humans↗
Biomedical subjects
S H Hohnloser
Publications and source records attributed to S H Hohnloser.
Analysis of creatine kinase, CK-MB, myoglobin, and troponin T time-activity curves for early assessment of coronary artery reperfusion after intravenous thrombolysis.
BACKGROUND: Thrombolysis has become the standard therapeutic approach in patients with acute myocardial infarction. To identify patients who may benefit from early invasive procedures, reliable noninvasive assessment of success or failure of thrombolytic therapy is mandatory. METHODS AND RESULTS: In a prospective study in 63 consecutive patients undergoing thrombolysis for their first myocardial infarction, serial measurements of creatine kinase (CK), its isoenzyme CK-MB, myoglobin, and troponin T were done to determine their value for noninvasive prediction of coronary artery patency. Blood samples were drawn every 15 minutes during the first 90 minutes, every 30 minutes during the first 4 hours, every 4 hours during the first 24 hours, and every 8 hours during the first 72 hours. The perfusion status of the infarct-related artery was assessed angiographically 90 minutes after initiation of thrombolysis. For each marker, time to its peak concentration and its early initial slope (start of thrombolysis to 90 minutes thereafter) were determined. Areas under receiver operator characteristic (ROC) curves were 0.83, 0.76, 0.82, and 0.80 for maxima of CK, CK-MB, myoglobin, and troponin T, respectively (p = NS by univariate Z test). The corresponding values for early slopes of CK, CK-MB, myoglobin, and troponin T were 0.79, 0.82, 0.89, and 0.80 (p = 0.23 for comparison between myoglobin and CK-MB; p = 0.07 between myoglobin and CK). Sensitivity, specificity, and positive and negative predictive values regarding noninvasive prediction of coronary artery patency after 90 minutes were 80%, 82%, 95%, and 61% for time to CK maximum; 91%, 77%, 91%, and 77% for time to myoglobin maximum; 87%, 71%, 89%, and 67% for early CK slope; and 94%, 88%, 94%, and 82% for myoglobin slope, respectively. When myoglobin slope was assessed together with other clinical reperfusion markers (resolution of chest pain or ST segment elevation, occurrence of reperfusion arrhythmias) by logistic regression analysis, only the myoglobin slope was an independent predictor of coronary artery patency (p < 0.0001). CONCLUSIONS: With regard to noninvasive prediction of coronary artery patency after thrombolytic therapy, measurement of the early initial slopes of the serum markers within only 90 minutes after the initiation of therapy is as accurate as the determination of the time to their peak concentration. Compared with the other markers examined, myoglobin appears to have advantages because of its earlier rise, yielding a better negative predictive value and a higher area under the ROC curve for determination of its early initial slopes.
Adult↗
[QT-dispersion in the surface ECG as a parameter of increased electrical vulnerability in acute myocardial ischemia].
QT-dispersion defined as the difference between QTmax and QTmin in the 12-lead surface ECG was determined in 33 patients with acute myocardial infarction treated by intravenous thrombolysis. In 11 patients, ventricular fibrillation ensured during the first 24 h after hospital admission. These patients were then compared with 22 matching infarction patients without malignant ventricular rhythm disturbances. QT-dispersion as evaluated in the first ECG taken after hospital admission was significantly higher in patients with (88 +/- 16 ms) compared to QT-dispersion in patients without ventricular fibrillation (66 +/- 19 ms; p < 0.001). When QT-dispersion was again assessed in ECG tracings recorded prior to hospital discharge, it was markedly reduced, with no significant difference between either patient group (53 +/- 16 ms versus 54 +/- 18 ms). These results indicate that QT-dispersion in the surface ECG represents a marker of inhomogeneous repolarization in patients with acute myocardial infarction prone to ventricular fibrillation. This may allow early identification of high-risk patients soon after hospital admission.
Adrenergic beta-Antagonists↗
[Reproducibility of heart rate variability measurements in repeated 24-hour long-term ECG registration].
Heart rate variability (HRV) is considered to indicate cardiac autonomic reflex activity. The reproducibility of HRV determinations from repeated Holter recordings has not been vigorously evaluated. This represents, however, an important question since HRV determinations are increasingly used to examine disease-related changes in the autonomic tone or the effects of therapeutic interventions. Thus, the present study examined the reproducibility of 4 commonly used time-domain parameters (SDNN, SDANN, rMSSD, pNN50) and the spectral components of HRV in 17 healthy volunteers and in patients with coronary artery disease (n = 9) or hypertensive heart disease (n = 9). In all subjects, 2 Holter recordings were obtained 7 days apart. In both, healthy volunteers and in patients, overall reproducibility of HRV parameters was good exhibiting correlation coefficients between 0.60 and 0.98. However, in individual subjects particularly in those without heart disease a higher degree of variability of HRV measurements was observed. In those patients with markedly reduced HRV, reproducibility was best. It is concluded that repeated HRV determinations may be utilized to examine the effects of underlying disease progress or of therapeutic interventions on cardiac autonomic tone.
Adult↗
[Intra-individual reproducibility of tilt table studies in diagnosis of vasovagal syncope].
Neurally-induced syncope appears to be the underlying pathophysiologic mechanism in many patients with unexplained syncope. Diagnosis of vasovagal syncope, however, remains difficult and constitutes in many cases an exclusion diagnosis. The present study thus aimed to determine the yield of tilt-table testing in the work-up of patients with unexplained syncope and most importantly to examine the reproducibility of the results of this method. Twenty-four patients with a history of syncope and 11 healthy volunteers were examined on 2 days. In 10 patients, symptoms could be provoked during tilting, in 8 during both tests, in 2 only on one occasion. Only 1 of 11 volunteers developed presyncope during tilting which was not reproducible during the second test. These findings resulted in a sensitivity of 42% and a specificity of 91% for the protocol employed in this study. Overall reproducibility was 91% which suggests that this tilt-table protocol is suitable for evaluation of therapeutic interventions in patients with neurally-mediated syncope.
Adult↗
Short- and long-term efficacy and safety of flecainide acetate for supraventricular arrhythmias.
This report summarizes efficacy and safety data on the use of flecainide acetate for supraventricular arrhythmias. For this purpose, 60 original articles were identified by a literature search representing data from 1,835 treatment courses. In 18 trials, flecainide was administered intravenously; in 19, orally; and in 23, both forms of therapy were applied. There were 5 placebo-controlled and 12 comparative studies, whereas data from uncontrolled studies were represented in 43 articles. Short-term flecainide administration terminated atrial fibrillation in 65% of attempts and terminated atrial flutter in 28%. The drug was effective during long-term therapy for atrial fibrillation in 49% of patients, with similar efficacy rates in 11 comparative trials and in 16 uncontrolled studies. In randomized, placebo-controlled studies in patients with paroxysmal atrial fibrillation, flecainide was shown to reduce significantly the number of attacks, to prolong the time between attacks, and to improve quality of life. In patients with atrioventricular (AV) reciprocating tachycardias, acute drug administration was successful in 72%; 83% of patients with AV nodal reentrant tachycardias and 74% exhibiting arrhythmias associated with the Wolff-Parkinson-White syndrome responded acutely. During long-term therapy, efficacy rates were 70%, 78%, and 69%, respectively. Ectopic atrial tachycardia responded in 86% and 95% of patients treated with flecainide acutely or chronically. Data concerning drug-related side effects were available for 1,794 of 1,835 treatment courses (98%). Overall, 352 of 1,794 patients (20%) reported at least one non-cardiac or cardiac adverse experience.(ABSTRACT TRUNCATED AT 250 WORDS)
Arrhythmias, Cardiac↗
Arrhythmias during the acute phase of reperfusion therapy for acute myocardial infarction: effects of beta-adrenergic blockade.
In 107 patients with acute myocardial infarction, the incidence of ventricular arrhythmias during the acute phase of thrombolysis was examined by means of Holter monitoring. In patients with a patient infarct-related artery as assessed angiographically at 90 minutes, the occurrence of accelerated idioventricular rhythms was noted significantly more frequently than in patients with a permanent occluded vessel. This arrhythmia peaked in the first 180 minutes after the start of thrombolysis. In addition, single ventricular premature beats and runs of ventricular tachycardia were also more common in patients with successful reperfusion. The effects of acute intravenous administration of beta-blockers were examined in 66 patients without contraindications to this therapeutic approach. There were no differences in the occurrence of any type of rhythm disorders in patients with (n = 43) or without beta-blockade (n = 23). Thus ventricular arrhythmias particularly accelerated idioventricular rhythms, and single ventricular premature beats occur more frequently in patients with a patent infarct artery within the first 24 hours after thrombolysis. Acute intravenous beta-blockade does not appear to exert significant antiarrhythmic effects during this period.
Adrenergic beta-Antagonists↗
Efficacy and safety of sotalol in patients with complex ventricular arrhythmias.
Sotalol is a unique beta-blocker that prolongs repolarization. Its use in 626 patients with complex ventricular ectopic activity, as reported in the literature, resulted in suppression of arrhythmia in 50 to 60% of treatment attempts. Detailed analysis of data on arrhythmias in 356 patients that were entered prospectively into a database revealed a median reduction in ventricular premature beats of 76%, compared to a median suppression of repetitive ventricular ectopic activity of 91% and of episodes of nonsustained ventricular tachycardia of 97% (p = 0.002 vs reduction of ventricular premature beats). This marked antiarrhythmic potency of sotalol in repetitive ventricular arrhythmias is thought to be due to its class III activity. Drug efficacy was independent of age, sex, the presence or absence of organic heart disease and the degree of sotalol-induced prolongation of corrected QT interval. Evaluation of left ventricular function in 215 patients treated with the drug demonstrated that depression of left ventricular ejection fraction occurred far less frequently than expected with conventional beta-blockers. Even patients with severely depressed pump function tolerated sotalol surprisingly well. There is a propensity of the drug to aggravate arrhythmia, which resulted in serious proarrhythmic events in 30 (3.5%) of 853 patients. These often consisted of torsades de pointes (9 of 30 patients). Proarrhythmia occurred primarily within the first 3 days of dosing, and exhibited a dose-dependence. In conclusion, sotalol is an effective and well-tolerated antiarrhythmic drug in patients with complex ventricular ectopic activity.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Short- and long-term antiarrhythmic and hemodynamic effects of d,l-sotalol in patients with symptomatic ventricular arrhythmias.
The antiarrhythmic and hemodynamic effects of sotalol (160 to 480 mg/day), a beta-blocking agent that prolongs ventricular repolarization, were examined in 38 patients with complex symptomatic ventricular ectopic activity. During ambulatory monitoring, 24 patients (63%) exhibited a reduction of greater than 75% in single ventricular premature beats (VPBs) and greater than 90% reduction in repetitive arrhythmia. In contrast to the effects of other agents, left ventricular ejection fraction as determined by radionuclide angiography was not impaired, increasing slightly from 45 +/- 14% to 47 +/- 14% during therapy (p less than 0.05). Antiarrhythmic drug efficacy did not correlate with baseline ejection fraction or sotalol-induced changes in ventricular function. Late follow-up studies disclosed that antiarrhythmic efficacy and tolerance were maintained in the majority of patients. Repeat radionuclide angiography at 6 months revealed no late drug-induced depression of left ventricular function. Sotalol appears to be an effective and well tolerated agent for treatment of complex ventricular ectopic activity, even in the setting of compromised cardiac function.
Adult↗
ST segment analysis for assessment of coronary artery patency: comparison of surface ECG and Holter recordings.
In a prospective trial in 124 patients with acute myocardial infarction, Holter and surface ECG recordings were obtained simultaneously and compared for their ability to assess thrombolysis-induced ST segment changes. Accuracy in predicting patency of the infarct-related artery was evaluated in both methods. Success or failure of thrombolysis was determined angiographically 90 min after the start of therapy. For both methods, sensitivity, specificity, and positive predictive value for correct prediction of the perfusion status ranged between 64% and 92%. However, the negative predictive value was considerably lower (40-53%). There were no significant differences in any parameter evaluated for either method. Thus, two surface ECG recordings before and 2 h after the start of therapy yield the same predictive value as continuous Holter monitoring with respect to thrombolysis-induced coronary artery reperfusion. However, for triage of patients to early coronary interventions, more sophisticated methods are needed for non-invasive prediction of coronary artery patency due to the low negative predictive value of ST segment analysis.
Adult↗
Intraindividual reproducibility of heart rate variability.
Heart rate variability was determined from three consecutive Holter recordings performed on days 1, 7, and 28 in 17 normal subjects, in 13 patients with angiographically normal coronary arteries, and in 9 patients with remote myocardial infarctions. Group data of several time and frequency domain measures of heart rate variability were highly reproducible (correlation coefficients 0.629-0.894). However, some individuals exhibited considerably larger day-to-day variations in heart rate variability. Single heart rate indices differed by up to 50% between two Holter recordings. Such potential differences must be considered when repeated heart rate variability determinations are used to assess changes in neurocardiac reflex regulation or effects of therapeutic interventions.
Chest Pain↗
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↗
[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↗
[Anti-arrhythmia drugs in geriatric patients].
Owing to the special pharmacodynamic and pharmacokinetic situation in the aged, the therapeutic spectrum of antiarrhythmic agents is very narrow. The indication for these substances must be established in accordance with strict criteria. Once indicated, antiarrhythmic drug therapy must be initiated at the lowest possible dose, and increases in dosage must be gradual. Non-controlled empirical treatment with such drugs rejected, and the success or lack of success of such treatment must be checked using suitable methods, for example, Holter monitoring. Since the patients often have multiple diseases, particular attention must be paid to interactions with other drugs. Careful consideration must be given to the possibility of Cardiac side effects of antiarrhythmic agents such as proarrhythmic or negative inotropic effects.
Aged↗
Usefulness of esmolol in unstable angina pectoris. European Esmolol Study Group.
Esmolol is a new cardioselective beta blocker with unique pharmacokinetic properties resulting in a half-life of only 9 minutes. The present multicenter, randomized, placebo-controlled study examined the hemodynamic and antiischemic effects of this compound given as an adjunctive to conventional medical therapy in 113 patients with unstable angina. Fifty-nine patients received esmolol and 54 received matching placebo infusions. Esmolol was titrated in a step-wise manner at dosages of 2 to 24 mg/min until a 25% reduction in the double product was achieved; thereafter, esmolol was continuously infused for up to 72 hours. Esmolol caused a significant and persistent decline in heart rate and blood pressure throughout the entire study period. Clinical events, such as development of acute myocardial infarction or the need for urgent revascularization, occurred in 3 esmolol compared with 9 placebo patients (p = 0.06). There was also a trend toward reduction of silent ischemia as judged by Holter monitoring (mean [+/- standard deviation] duration/patient/24 hours, 21 +/- 81 minutes in the esmolol and 35 +/- 128 minutes in the placebo groups). Esmolol-related adverse effects were mostly cardiovascular in origin and could be managed promptly by downward dose titration or cessation of drug infusion. Thus, esmolol appears to be a safe and effective drug for patients with unstable angina because it permits a large degree of flexibility in adapting the desired level of beta blockade to the patient's changing clinical presentation.
Adrenergic beta-Antagonists↗
Electrocardiographic and antiarrhythmic effects of intravenous amiodarone: results of a prospective, placebo-controlled study.
The antiarrhythmic efficacy of intravenously administered amiodarone was examined in a prospective, randomized, placebo-controlled study that involved 77 patients after coronary artery bypass surgery. Amiodarone was given after surgery in a loading bolus of 300 mg for 2 hours followed by 1200 mg every 24 hours for 2 days and 900 mg every 24 hours for the next 2 days. Amiodarone suppressed both supraventricular and ventricular arrhythmias within 12 hours after the start of therapy. Particularly, the incidence of atrial fibrillation (5% vs 21% in the control group; p less than 0.05) and of nonsustained ventricular tachycardia (3% vs 16%; p less than 0.05) was reduced by amiodarone. Heart rate was slowed (p less than 0.001) and repolarization--as judged by JTc interval--was prolonged compared with the control group (p less than 0.01). In two patients, amiodarone infusion was stopped because of excessive QTc prolongation. No detrimental hemodynamic effects of the drug were observed. Thus the intravenous administration of amiodarone appears to be suitable for patients in whom rapid suppression of symptomatic supraventricular and ventricular arrhythmias is warranted in the presence of left ventricular dysfunction.
Aged↗
Assessment of coronary artery patency after thrombolytic therapy: accurate prediction utilizing the combined analysis of three noninvasive markers.
The predictability of patency of the infarct-related artery assessed by means of three noninvasive easily obtainable markers was prospectively examined in 82 patients undergoing thrombolysis for their first myocardial infarction. Positive noninvasive markers were defined as follows: 1) early peak creatine kinase (CK) activity less than or equal to 12 h after the start of thrombolysis; 2) greater than or equal to 50% reduction in ST segment elevation; and 3) occurrence of reperfusion arrhythmias within the 1st 90 min of thrombolytic therapy. In 63 (77%) of the 82 patients, Thrombolysis in Myocardial Infarction (TIMI) grade II/III reperfusion was achieved within the 1st 90 min as assessed by coronary angiography. Separate analysis of each marker revealed the following respective values for sensitivity, specificity and positive and negative predictive value regarding prediction of coronary artery patency: CK peak less than or equal to 12 h: 84%, 95%, 98% and 64%; reduction of the ST segment elevation greater than or equal to 50%: 60%, 95%, 97% and 42%; and reperfusion arrhythmias: 63%, 89%, 95% and 43%. The combined analysis of all three markers utilizing a logistic regression procedure showed that CK peak (p = 0.0001) and resolution of the ST segment elevation (p = 0.005), but not the occurrence of reperfusion arrhythmias (p = 0.26), were independent predictors of vessel patency. From this logistic regression procedure, a sensitivity of 100%, a specificity of 90%, a positive predictive value of 97% and a negative predictive value of 100% for prediction of coronary artery patency were obtained.(ABSTRACT TRUNCATED AT 250 WORDS)
Arrhythmias, Cardiac↗
[Proarrhythmic effects of anti-arrhythmia agents].
Explore the source record for details and available documents.
Anti-Arrhythmia Agents↗