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H J Trappe

Publications and source records attributed to H J Trappe.

At least 19 recordsLinked to original sources
PubMed1992

[Results and experiences of transvenous endocardial defibrillator therapy].

We studied the follow-up of 72 patients who underwent implantation of a transvenous defibrillation lead system (ELS) (Endotak, CPI). All patients had ventricular tachycardia (VT) or fibrillation (VF) refractory to antiarrhythmic drug therapy. There were 51 patients with coronary disease and 21 patients had non-ischemic VT/VF. ELS was combined with a subcutaneous patch in 52 patients and implanted alone ("single lead only") in 20 patients. 40 patients received the ELS combined with antitachycardia pacing devices (Ventak PRx, CPI; Cadence, Ventritex) and 32 patients with the Ventak P 1600 or P2, CPI. Implantation of the ELS was attempted in 80 patients and performed in 72 patients (90%): Intraoperatively, the mean defibrillation threshold (DTF) was > 25 Joule (J) in five patients and no reliable ELS position was possible to achieve in three patients. These eight patients underwent thoracotomy with epicardial patch implantation. The mean DFT was < or = 20 J in all 72 patients with a mean DFT of 14 +/- 8 J in VT patients and 17 +/- 10 J in VF patients. Two of 80 patients (3%) died: one patient died intraoperatively and one during the mean follow-up of 6 +/- 2 (< 1 to 18) months. Complications occurred in three patients (4%): Dislocation of the Endotak electrode was observed in two patients (3%) and one patient developed pneumothorax postoperatively. Our data show that the ELS is most suitable in the majority of patients with VT/VF and is the approach of first choice for cardioverter defibrillator implantation at the present time. However, despite a relatively low intra- and perioperative complication rate, this approach should not be performed in institutions without cardiac surgery.

Adolescent↗
PubMed1992

Role of mapping-guided surgery in patients with recurrent ventricular tachycardia.

To assess the value of ventricular tachycardia (VT) surgery 108 patients with recurrent episodes of VT were studied. There were 97 patients with coronary artery disease (group I) and 11 patients without coronary artery disease (group II). All patients in group I underwent subendocardial resection; 12 patients also underwent cryoablation. Cryoablation alone was performed in all patients in group II. During a mean follow-up period of 40 +/- 27 months, 29 patients (30%) in group I and two patients (18%) in group II died (p = 0.33). There were nine patients (9%) in group I and six patients (55%) in group II who had nonfatal recurrences of VT after surgery (p less than 0.01). In group I, there was a higher mortality rate among patients who had VT of posterolateral origin (14 of 31 patients; 45%) compared with 3 of 11 patients (28%) who had VT of anterolateral origin, 1 of 8 patients (12%) who had VT of inferoseptal, and 11 of 39 (29%) patients who had VT of anteroseptal origin. None of the eight patients with two distinct origins of VT died.

Adult↗
PubMed1992

Surgical therapy for drug-refractory ventricular tachycardia: role of additional aneurysmectomy or bypass grafting.

To assess whether additional aneurysmectomy and/or bypass grafting influence prognosis we studied 97 patients with recurrent sustained monomorphic ventricular tachycardia after an old myocardial infarction. All patients underwent subendocardial resection due to drug-refractory ventricular tachycardia. There were 41 patients who had resection alone, 27 patients had resection and aneurysmectomy, 13 patients had resection and bypass grafting and the remaining 16 patients had resection with both, aneurysmectomy and bypass grafting. During the mean follow-up of 40 +/- 27 months 29 patients died (30%) (total mortality), 7 patients suddenly (7%) and 20 patients from cardiac causes (20%). There were no significant differences in total mortality between patients with resection alone (32%), patients with resection and aneurysmectomy (22%), patients with resection and bypass grafting (31%) and patients who had resection, aneurysmectomy and bypass grafting (38%). In addition, no significant differences were observed in the incidence of sudden death and nonfatal recurrences between patients with resection alone: sudden death 12%, recurrences 7%; patients with resection and aneurysmectomy: sudden death 0%, recurrences 19%; patients with resection and bypass grafting: sudden death 0%, recurrences 8%; and patients with resection, aneurysmectomy and bypass grafting: sudden death 13%, recurrences 0%. Postoperatively, left ventricular function improved in 56% of patients who had resection and aneurysmectomy compared to 17% of patients with resection alone, 31% of patients with resection and bypass grafting and 19% of patients who had resection, aneurysmectomy and bypass grafting. There is a low risk of sudden death and nonfatal recurrences after subendocardial resection. An influence of additional surgical approaches (aneurysmectomy or bypass grafting) on prognosis is not visible.

Adult↗
PubMed1992

Catheter ablation of ventricular tachycardia: role of the underlying etiology and the site of energy delivery.

The role of DC catheter ablation (CA) to treat patients with sustained monomorphic ventricular tachycardia (VT) is still debated. To assess the efficacy of VT CA, we studied the follow-up of 49 patients with VT who underwent CA. There were 33 patients with an old myocardial infarction (MI) (group G I) and 16 patients had noncoronary VT (group G II): CA was performed at the earliest endocardial activation (EEA) (20 patients in G I, 14 patients in G II) or at the area of slow conduction (ASC) (13 patients in G I, 2 patients in G II). During the mean follow-up of 35 +/- 25 (1-79) months, there were 17 patients in G I (52%) and 12 patients in G II (75%) with VT recurrences (P less than 0.05). Recurrences of VT was observed in 4 of 15 patients (27%) when CA was performed at the ASC, compared to 25 of 34 patients (74%) with CA at the EEA (P less than 0.01). These data show that DC CA is more successful in patients with coronary artery disease, particularly when CA is performed at the ASC.

Adult↗
PubMed1992

Effect on ventricular performance of direct current electrical shock for catheter ablation of the atrioventricular junction.

In ten patients undergoing catheter ablation of the atrioventricular junction (CAVJ) because of therapy refractoriness of supraventricular arrhythmias, the effect of repeated high energy direct current (DC) shock on left ventricular function has been investigated. End-systolic pressure-volume relation (ESPVR) and the positive first derivative of ventricular pressure (dP/dt) have been used as indices of left ventricular systolic function, while the time constant of isovolumic pressure decay, the diastolic stiffness, and the negative dP/dt represented the diastolic function parameters, respectively. Each patient received at least two and no more than three DC shocks for successful CAVJ, with an energy of 360 joules. Significant acute reduction of both systolic and diastolic function was noted after each DC shock, with a slow partial recovery of both phases. The recovery process involved the systolic phase earlier and more completely than the diastolic one. The alterations observed could not be predicted from preablation values, but were significantly related to cumulative energy dose index for body weight. In conclusion, repeated high energy DC shocks acutely, but reversibly, impair left ventricular function; in addition, the ventricular function reduction is primarily related to the total ablation energy indexed for body weight.

Adult↗
PubMed1992

[The x-ray clinical picture and evaluation criteria of implantable cardioverter-defibrillator systems].

Since the first implantation of an automatic cardioverter defibrillator (ICD) in February 1980, the therapy of ventricular tachyarrhythmia has been changed drastically. The original therapy with antiarrhythmic agents has been increasingly replaced by the implantation of the ICD. The radiologist should be aware of the different types of ICDs and their normal appearance, because thorax radiography is often used during regular routine follow-up of the ICD system. The different types of ICDs, their normal radiological appearances, the indications and the implantation technique are discussed in the present study. The radiologist has to interpret the radiographs with respect to the electrodes, the device and changes in heart configuration. Major migration of electrodes is visible, but the detection of little changes in configuration is only possible with the help of serial radiographs. If extraperitoneal placement of the device is suspected, an ultrasound examination should be obtained. An important complication for the radiologist is a possible deactivation of some devices by electromagnetic interference.

Contraindications↗
PubMed1992

[Implantable defibrillators].

Automatic implantable defibrillator therapy has changed the approach to life-threatening ventricular tachycardia completely and essentially improved survival after aborted sudden cardiac death. Since the first implantation of a defibrillator in 1980, 20,000 patients have received such a device. Nonetheless, in Germany still too many patients die of sudden cardiac death because defibrillator therapy fails to be known enough and keeps not being made use of (no more than 1,000 implants to date). In this group of patients characterized by poor ventricular function, antiarrhythmic drug therapy proved to be unreliable or even dangerous in many cases, while electrophysiologically-guided surgical interventions use to be impossible. The introduction of the implantable defibrillator enabled the incidence of sudden cardiac death to be reduced to about 2% during the first year after implant, and to 5% in the third year, respectively. In most centers with more extensive experience in defibrillator implantations, operative mortality is about 2-3%. Long-term results with defibrillator patients are controlled by the course of the underlying disease, which is coronary artery disease with large scars due to infarction in some 75% of cases. In a large group of about 10,000 patients, total mortality has been calculated to be 15% after three years. Defibrillator systems of the latest generation offer multiple programmability of tachycardia identification parameters and permit differentiated modification of therapeutic intervention. Defibrillator therapy has now been improved essentially by the introduction of endocardial lead systems and, in addition, by the defibrillator being combined with an antitachycardia pacing system.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Pacing, Artificial↗
PubMed1992

[Long-term follow-up of patients after interruption of the atrioventricular conduction by electrode catheter and DC shock: experiences with 100 patients].

Long-term follow-up (44 +/- 21 months) was studied in 100 patients (pts) (mean age 56 +/- 12 years) who underwent direct current ablation because of drug-resistant supraventricular arrhythmias. In 85 pts (85%) complete atrioventricular (AV) block was initially achieved. During the follow-up period, AV conduction resumed in 15 pts (15%). Thirteen pts underwent another ablation session and complete AV block was achieved in 11/13 pts (85%). After catheter ablation complete AV-block was achieved in 96 pts and the remaining four pts had second-degree AV-block. Complications like pericardial effusion, arterial hypotension or ventricular arrhythmias occurred in 18 pts. Total mortality was 13% (13 pts): one patient died suddenly, and seven pts died from cardiac causes (heart failure in six pts, reinfarction in one patient). Transcatheter direct-current ablation is an effective method to interrupt AV conduction and to treat patients with drug-resistant supraventricular arrhythmias. Although there is a small risk of severe complications, this procedure should be reserved for pts with supraventricular arrhythmias who do not respond to conventional drug treatment.

Adult↗
PubMed1991

Lack of prognostic value of syncope in patients with Wolff-Parkinson-White syndrome.

Syncope in patients with Wolff-Parkinson-White syndrome may be considered a premonitory event heralding the future development of sudden death. Therefore, the clinical and electrophysiologic data of 101 patients with Wolff-Parkinson-White syndrome referred for invasive evaluation of known arrhythmias were reviewed to assess the incidence and clinical relevance of syncope. Thirty-six patients reported the occurrence of one or more syncopal episodes (group 1) and 65 patients had no syncope (group 2). These two groups did not differ significantly with regard to age, gender, incidence and characteristics of arrhythmia, clinical history, frequency of arrhythmic events and presence of associated cardiac disease. There were 10 patients in group 1 and 12 in group 2 who had ventricular fibrillation. There were no statistical differences between the two groups with respect to the effective refractory period of the right atrium, atrioventricular node, accessory pathway and right ventricle. Furthermore, no differences between the two groups were noted with respect to cycle length of circus movement tachycardia, mean heart rate during atrial fibrillation, and minimum RR interval during atrial fibrillation. In addition, the accessory pathway location was not significantly different between group 1 and group 2. The occurrence of syncope could not be predicted from any electrophysiologic finding and this symptom had a low sensitivity and specificity for recognition of dangerous rapid heart rates. Furthermore, the prognostic value of syncope was less accurate and predictive than the shortest RR interval during atrial fibrillation and the anterograde effective refractory period of the accessory pathway for aborted sudden death occurrence.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Significance of catheter ablation as emergency intervention in patients with sustained monomorphic ventricular tachycardia].

Treatment of incessant ventricular tachycardia (VT) refractory to antiarrhythmic drugs and DC cardioversion is difficult and still debated. We performed catheter ablation (CA) of sustained monomorphic ventricular tachycardias (VT) with high-energy DC shock (360-400 Joule) in 11 patients (pts) with incessant VT (duration greater than 24 h), refractory to antiarrhythmic drugs and DC cardioversion. Ten pts suffered from coronary disease and one pt from dilated cardiomyopathy. DC energy was delivered either at the site of the earliest endocardial activation (EEA) (six pts) or at the area of slow conduction (ASC) (five pts). In nine pts incessant VT could be terminated by DC ablation; two pts had to undergo emergency endocardial resection. During the mean follow-up of 31 +/- 26 (1-66) months nonfatal VT recurrences occurred in five pts with CA at the EEA and in one pt with CA at the ASC. We conclude that CA of incessant VT is an effective approach to terminate VT. However, there is a high incidence of nonfatal recurrence after CA, particularly when DC energy is delivered at the earliest site of endocardial activation.

Adult↗
PubMed1990

Circadian distribution of the characteristics of ischemic episodes in patients with stable coronary artery disease.

To determine the circadian distribution of episodes of myocardial ischemia, studies were performed in 111 patients with chronic stable angina pectoris, positive exercise test results and angiographically proven coronary artery disease. During 24 hours of ambulatory electrocardiographic monitoring, 101 symptomatic and 298 asymptomatic ischemic episodes (ST-segment depression greater than 1 mm, duration greater than 1 minute) were observed. The number of ischemic episodes and the cumulative duration of ischemia showed a circadian variation with the highest values between 8 and 10 A.M. and between 4 and 5 P.M. associated with a similar circadian variation of heart rate. Mean duration of ischemic episodes, maximal amplitude of ST-segment depression during ischemic episodes and increase in heart rate before the onset of ischemic episodes showed no significant circadian variation. Heart rate at the onset of ischemic episodes and maximal heart rate during ischemic episodes were lower between midnight and A.M. than during other times of the day. The morning and afternoon increase in ischemic activity is not paralleled by changes reflecting a decrease in myocardial oxygen supply during these periods (heart rate at onset of ischemia, heart rate increase before onset of ischemia), but is paralleled by a similar circadian variation of heart rate. The circadian variation in ischemic activity is predominantly based on a comparable variation in myocardial oxygen requirements.

Circadian Rhythm↗
PubMed1990

Elimination of variable vasomotor tone in studies with repeated quantitative coronary angiography.

In quantitative coronary angiographic studies, unintentional changes of coronary vasomotor tone may have a significant influence on the coronary artery diameters, thereby increasing the variability in the measurements. To obtain objective data on these measurement variabilities, two protocols were designed to assess the influences of ionic and nonionic radiographic contrast media on the mean diameters of angiographically normal coronary arteries. The vessel sizes were determined with the CAAS using automated edge detection techniques. In 21 patients (study no. I), coronary angiograms were taken in identical angiographic projections before (control), and immediately following several (at average 7) subsequent diagnostic dye injections administered over a period of about 7 min. The ionic contrast agent diatrizoate 76% induced a coronary dilation of 19 +/- 7% (mean +/- s.d., p less than 0.001; n = 10); the nonionic agent iopromide 370 increased the coronary artery diameters by only 6 +/- 4% (p less than 0.01; n = 11). In another 11 patients (study no. II) coronary angiograms were obtained using the nonionic contrast medium iopamidol 300 at 5, 8, 10 and 11 min after the control acquisition; this protocol was repeated in the same patients with diatrizoate 76%. With iopamidol, coronary diameter changes were not significant at any time; with diatrizoate, however, coronary dilation was measured at 10 min (2 +/- 2%; p less than 0.01) and at 11 min (10 +/- 3%; p less than 0.001). In a third study it was tested, whether standardization of coronary vasomotor tone (e.g. in coronary angiographic follow-up studies) is possible by the induction of a reproducible maximum coronary dilation with nitrocompounds. In 12 patients, the mean diameters of angiographically normal coronary segments were analyzed before and at various times after i.v. administration (over 4 min) of 0.025 mg SIN-1/kg bodyweight. Coronary dilation was maximal at 10 or 15 min after the onset of the SIN-1-infusion (29 +/- 5%; p less than 0.001). 0.8 mg nitroglycerin given s.l. at 15 min did not further dilate the coronary arteries (28 +/- 7%). One hour after SIN-1, coronary dilation still amounted to an average of 24 +/- 8% (p less than 0.001) and became 'maximal' again, when 0.8 mg nitroglycerin was again administered sublingually (28 +/- 8%; p less than 0.001). In conclusion, short-term variability of coronary vasomotor tone induced by ionic radiographic contrast media can be eliminated by the use of nonionic contrast agents and observation of injection intervals of at least 2 min. In quantitative coronary angiographic follow-up studies, as well as during acute interventions (e.g., PTCA), identical baseline vasomotor tone can be achieved by induction of the maximal coronary dilation using nitrocompounds.

Adult↗
PubMed1990

Sotalol in patients with life-threatening ventricular tachyarrhythmias.

To assess the antiarrhythmic efficacy of oral d,l-sotalol, 68 patients with sustained monomorphic ventricular tachycardia (SMVT) (n = 62) or ventricular fibrillation (VF) (n = 6) were studied by programmed ventricular stimulation (PVS). Fifty-one patients had coronary artery disease with a previous myocardial infarction and there were 17 patients without coronary disease: 11 patients had right and/or left ventricular dysplasia, one patient an aortic-valve replacement, and five patients had no visible heart disease. Prior to sotalol patients were treated with a mean of 3.6 +/- 1.3 antiarrhythmic class I drugs. None of these drugs prevented SMVT or VF. During control PVS (PVS 1), VF was induced in 8 patients (12%), SMVT in 47 patients (69%), and nonsustained ventricular tachycardia (NSVT) in 13 patients (19%). After loading with oral d,l-sotalol (320 mg/day), PVS (PVS 2) was repeated 4.2 +/- 3.3 weeks after PVS 1. In one of the patients (1%) VF was inducible, in 15 patients (22%) SMVT was induced, and in 18 patients (26%) NSVT was induced. In 34 patients (50%) either no or a short ventricular response was inducible. Our data show that oral d,l-sotalol is an effective antiarrhythmic agent in patients with SMVT or VF.

Adult↗
PubMed1990

Incidence of ventricular arrhythmias during transient myocardial ischemia in patients with stable coronary artery disease.

To determine the incidence of ventricular arrhythmias related to episodes of transient myocardial ischemia during ambulatory electrocardiographic (ECG) monitoring, 97 patients with stable angina pectoris, angiographically proved coronary artery disease and an abnormal exercise test were studied. A total of 573 episodes with ST segment depression were documented: in 118 episodes (21%) the patients were symptomatic and in 455 (79%) they remained asymptomatic. Ventricular arrhythmias (greater than 5 premature ventricular beats/min, bigeminy, couplets or salvos of premature ventricular beats) occurred during 27 (5%) ischemic episodes in a subset of 10 patients (10%) (group A). The other 87 patients (90%) (group B) showed exclusively ischemic episodes without ventricular arrhythmias. Comparison of patients in group A and group B showed no differences in hemodynamic, angiographic, exercise testing and ambulatory ECG monitoring data. Ischemic episodes with and without ventricular arrhythmias showed a similar duration and amplitude of ST segment depression and a comparable heart rate at the onset of ischemia. Both types of ischemic episodes, with and without arrhythmias, occurred predominantly during the morning hours between 6:00 AM and noon, and both types remained asymptomatic to within similar percentages. The data demonstrate that ventricular arrhythmias are related to transient myocardial ischemia in only a few patients with stable angina pectoris; these arrhythmias are related neither to the degree of ischemia during ambulatory ECG monitoring nor to the occurrence of anginal symptoms.

Adult↗
PubMed1990

[Prognostic significance of syncope in patients with Wolff-Parkinson-White syndrome].

The prognostic value of syncope in symptomatic patients with Wolff-Parkinson-White syndrome (WPW) is unknown. Therefore, in order to evaluate the sensibility, specificity, positive and negative predictive value of syncope and compare those values with the one obtained for the shortest RR interval (less than or equal to 250 msec) as well as for the anterograde refractory period of the accessory pathway (less than 270 msec), we reviewed the clinical and electrophysiological data of 158 symptomatic patients with WPW. Fourty-eight patients (30%) reported at least one episode of syncope, and 24 out of 158 patients experienced an aborted sudden death, probably due to rapid conduction via the accessory pathway during atrial fibrillation. Syncope has poor sensibility but high specificity in recognizing an aborted sudden death. However, the syncope demonstrated it had a lower prognostic value when compared with other electrophysiological parameters in correctly identifying patients with a history of ventricular tachycardia and/or fibrillation. In conclusion, the data of this study propose the symptom "syncope" as a frequent event in the history of symptomatic patients with WPW referred to electrophysiological study. Generally its presence does not correctly identify patients who experienced an aborted sudden death. Furthermore, its prognostic value is significantly lower than a shorter RR interval (less than or equal to 250 msec) during atrial fibrillation and an anterograde effective refractory period less than 270 msec.

Adult↗
PubMed1990

[The implantable automatic cardioverter-defibrillator].

In addition to medical treatment for ventricular tachyarrhythmias which has not proven to be sufficient, nonmedical modes of treatment are available such as electrophysiologically-guided surgical measures and catheter ablation, both of which are restricted to only a relatively small patient population and require further technical refinement. In 1980, Mirowski introduced the automatic implantable defibrillator and, to date, world-wide, this device has been implanted in 8000 patients. CHARACTERISTICS AND IMPLANTATION OF THE AUTOMATIC IMPLANTABLE CARDIOVERTER/DEFIBRILLATOR (AICD): The AICD continuously monitors the electrical activity of the heart, recognizes the onset of threatening ventricular tachycardias and terminates these according to the respectively programmed mode by delivering direct current shocks or stimuli. The currently used defibrillators consist of an impulse generator with lithium batteries and an electrode system. The batteries can charge a capacitor with about 700 volts in five to eight seconds which produces a current with an energy up to 30 Joules on discharge. The current is delivered either by two plate electrodes on the right and left ventricles or a plate electrode on the left ventricle and a spiral electrode inserted in the superior vena cava. The electrodes also serve the purpose of tachycardia detection by means of an electrical signal, the probability density function (PDF), that is, a significant decrease in the potentials to isoelectric. With this, it is only possible to terminate ventricular fibrillation. Additional electrical detection criteria are obtained and analyzed by two adjacently positioned epicardial screw electrodes or a bipolar endocardial electrode, enable identification of ventricular tachycardia as well. If the tachycardia detection criteria are fulfilled, the capacitor is discharged according to its programmed shock energy. In 1988, programmable defibrillators were introduced. Current defibrillator treatment also incorporates the possibility for antitachycardia stimulation. Attempts to use, instead of the monophase, square-wave impulse, a biphasic defibrillation impulse, to achieve a sequential impulse and to make use of the bidirectional impulse extension have rendered improved reliability for tachycardia termination and energy savings. After median sternotomy, the plate electrodes are usually sutured to the epicardium and the spiral electrode for the bipolar ECG is positioned at the anterior aspect of the right ventricle. The generator is implanted on the left side para-umbilically in subcutaneous or subfascial tissue. With the subxyphoid approach to avoid sternotomy, the plate electrode is sutured extrapericardially over the left ventricle and the spiral electrode is positioned at the epicardium. Alternatively, for those in whom prior cardiac surgery has been carried out, a lateral thoracotomy can be used. The defibrillation threshold, that is the lowest possible energy for defibrillation of ventricular fibrillation or ventricular tachycardia, should be determined intraoperatively after stimulation of the arrhythmia. The energy required for termination of a stable ventricular tachycardia is usually less than that for termination of ventricular fibrillation and can be determined postoperatively. A margin of security should be taken into consideration which, for defibrillation thresholds of up to 10 Joules, is about twice the amount of the defibrillation threshold itself.(ABSTRACT TRUNCATED AT 400 WORDS)

Electric Countershock↗