Multicenter registry to evaluate the efficacy of the NIROYAL stent in de novo or restenotic coronary stenosis.

The purpose of this registry was to document the safety and efficacy of elective deployment of the NIROYAL stent (Boston Scientific SCIMED, Maple Grove, Minnesota) in coronary arteries. This was a prospective, multi-center international registry. NIROYAL stents (9, 16, 25 and 32 mm-long) were manually crimped onto coronary balloons and deployed in de novo or restenotic lesions in 165 male and female patients with angina pectoris and a reference vessel diameter of 2.0-4.5 mm. Stent deployment was successful in 98.8% of the lesions. Mean percent diameter stenosis decreased from 83.5+/-10.8% to 2.7+/- 6.2% after intervention. The interventional procedure of the treatment site was successful in 97.6% of patients. At six-month clinical follow-up, 88.5% had event-free survival [i.e., did not experience a major adverse cardiac event (MACE)] and 95.2% had no anginal symptoms. Furthermore, 87.3% of the patients were free of target vessel failure (defined as a composite of acute procedural failure, target vessel revascularization, myocardial infarction or death at six months). Only three MACE were observed within the first 30 days after stent implantation. A low left ventricular ejection fraction and the percentage stenosis pre-procedure were identified as statistically significant (p<0.05) predictive factors for MACE. The incidences of MACE and target vessel failure after six months follow-up were lower than that seen in other studies, and target lesion revascularization rates were low.

Primary angioplasty versus thrombolysis in the treatment of acute myocardial infarction. ALKK Study Group.

This study investigates the hypothesis if primary angioplasty is superior to intravenous thrombolysis in the treatment of acute myocardial infarction (AMI). Small prospective randomized studies did not demonstrate a significant benefit regarding total mortality. A total of 14,980 patients with AMI were registered by "The 60-Minutes Myocardial Infarction Project," a prospective multicenter observational study: 210 of these patients were treated with primary angioplasty. A matched pair analysis comparing 1 primary angioplasty patient with 3 intravenous thrombolysis patients could be performed in 156 primary angioplasty patients. Criteria for matching were age, sex, location of AMI, systolic blood pressure, previous AMI, and prehospital delay. Patients with a bundle branch block or requiring resuscitation were excluded from analysis. Because of matching, both groups showed similar baseline characteristics. Patients with primary angioplasty had more relative contraindications for thrombolysis (ulcers: 10.3% vs 2.3%, recent intramuscular injections: 6.4% vs 1.6%, recent surgical interventions: 5.1% vs 1.1%, central punctures: 9% vs 3.9%). There was a tendency toward less combined adverse events in the primary angioplasty group (3.2% vs 5.7%, odds ratio [OR] = 0.55, 95% confidence interval [CI] = 0.21 to 1.44). In-hospital mortality rates in the primary angioplasty group and thrombolysis group were 4.3% and 10.3%, respectively (OR = 0.39, 95% CI = 0.17 to 0.92). The difference in mortality could already be demonstrated within the first 48 hours with 1.9% versus 5.3% deaths (OR = 0.35, 95% CI = 0.11 to 1.14). Thus this study indicates a superiority of primary angioplasty in comparison to intravenous thrombolysis in AMI even in a clinical routine setting, with a reduction of hospital mortality of about 60%.

Atypical Kawasaki syndrome: how many symptoms have to be present?

A 20 year old woman with acute myocardial infarction exhibited a huge aneurysm of the left main coronary artery that was occluded by a large intraluminal thrombus. After exclusion of other vascular or systemic diseases, atypical Kawasaki syndrome was diagnosed. Other major symptoms usually required for this diagnosis were absent. As patients with Kawasaki syndrome in childhood are surviving longer, acute coronary symptoms may occur in young adults, and coronary aneurysms might be the only symptom of atypical Kawasaki syndrome.

[Splenic infarction caused by paradoxical emboli in severe pulmonary hypertension]. / Milzinfarkte durch paradoxe Embolie bei schwerer pulmonaler Hypertonie.

HISTORY AND CLINICAL FINDINGS: A 55-year-old woman developed increasing shortness of breath and breath-independent pain in the left lower chest. 20 years previously she had had an episode of pulmonary embolism and 10 years previously a central venous thrombosis in the left eye. No cause of the increased thrombogenesis had been found. On admission she had resting dyspnoea but a stable circulation. On auscultation the breath sounds were diminished over the left base and there was a diastolic murmur over the pulmonary area with an accentuated second sound. There was also marked tenderness below the left costal margin. Recurrent pulmonary embolism or left-sided pleuropneumonia was suspected. INVESTIGATION: Arterial blood gases (without additional oxygen) showed severe hypoxaemia (pO2 42.3 mm Hg, pCO2 27.8 mm Hg, pH 7.455, oxygen saturation 80.5%). Transthoracic and transoesophageal echocardiography showed normal left ventricular dimensions, right atrial and ventricular dilatation, and an atrial septal aneurysm with a right to left interatrial shunt. Right heart catheterisation demonstrated severe pulmonary hypertension. Sonography, computed tomography and scintigraphy revealed multiple splenic infarcts. TREATMENT AND COURSE: Heparinisation was instituted (partial thromboplastin time 70-90 s) and overlapping oral anticoagulation to a Quick value of 20%. Subsequently the calcium antagonist felodipine (15 mg daily) was given. The mean pulmonary artery pressure was 61 mm Hg before and 57 mm Hg after treatment. CONCLUSION: Splenic infarction resulting from paradoxical embolisation is rare, but should be routinely considered in the presence of thromboembolic phenomena.

Improved thrombolysis in acute myocardial infarction with front-loaded administration of alteplase: results of the rt-PA-APSAC patency study (TAPS)

Thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) and anisoylated plasminogen streptokinase activator (APSAC) in myocardial infarction has been proved to reduce mortality. A new front-loaded infusion regimen of 100 mg of rt-PA with an initial bolus dose of 15 mg followed by an infusion of 50 mg over 30 min and 35 mg over 60 min has been reported to yield higher patency rates than those achieved with standard regimens of thrombolytic treatment. The effects of this front-loaded administration of rt-PA versus those obtained with APSAC on early patency and reocclusion of infarct-related coronary arteries were investigated in a randomized multicenter trial in 421 patients with acute myocardial infarction. Coronary angiography 90 min after the start of treatment revealed a patent infarct-related artery (Thrombolysis in Myocardial Infarction [TIMI] grade 2 or 3) in 84.4% of 199 patients given rt-PA versus 70.3% of 202 patients given APSAC (p = 0.0007). Early reocclusion within 24 to 48 h was documented in 10.3% of 174 patients given rt-PA versus 2.5% of 163 patients given APSAC. Late reocclusion within 21 days was observed in 2.6% of 152 patients given rt-PA versus 6.3% of 159 patients given APSAC. There were 5 in-hospital deaths (2.4%) in the rt-PA group and 17 deaths (8.1%) in the APSAC group (p = 0.0095). The reinfarction rate was 3.8% and 4.8%, respectively. Peak serum creatine kinase and left ventricular ejection fraction at follow-up angiography were essentially identical in both treatment groups. There were more bleeding complications after APSAC (45% vs. 31%, p = 0.0019).(ABSTRACT TRUNCATED AT 250 WORDS)

Differences between atrial single chamber pacing (AAI) and ventricular single chamber pacing (VVI) with respect to prognosis and antiarrhythmic effect in patients with sick sinus syndrome.

Several studies suggest different effects of atrial (AAI) and ventricular single chamber pacing (VVI) for sick sinus syndrome with respect to the suppression of atrial tachycardias and to the prognosis. With this aspect in mind, we studied 222 patients with sick sinus syndrome, 110 of whom had been supplied with AAI systems, and 112 with VVI systems, in the period from January 1978 to December 1986. The mean observation period was 53 +/- 28 months. The cumulative 5-year survival rate was not significantly different in the two groups. After subgroups with comparable underlying diseases had been differentiated, patients with coronary heart disease showed a significantly higher survival rate (P less than 0.05) under AAI pacing, and the same was shown for patients with no underlying heart disease (P less than 0.02). The incidence of chronic atrial fibrillation was 6% in the AAI group and 19% in the VVI group. Patients with preexisting atrial tachyarrhythmias showed the lowest incidence of chronic atrial fibrillation under AAI pacing. Under VVI pacing this incidence was a function of the basic rate of the pacemaker systems. In conclusion, the pacing mode seems to have a prognostic importance in spite of all methodological difficulties. A suppressive effect of AAI pacing on atrial dysrhythmias can also be assumed.

[30 years cardiac pacemaker therapy: a status evaluation]. / 30 Jahre Herzschrittmachertherapie: Eine Standortbestimmung.

Antibradycardiac pacemaker therapy has become established as one of the most effective forms of cardiological therapy for the indications AV-block, sick sinus syndrome, bradyarrhythmia, and hypersensitive carotid sinus. About 220,000 systems are implanted per year worldwide, about 32,000 in West Germany. Of the pacing modes, the fixed-rate ventricular single chamber systems (VVI) dominate with a share of almost 90%. Prognostic importance: For AV-block, the improvement of the prognosis by pacemaker therapy is unquestionable, since it increases the cumulative survival rates to 81% and 95% after 1 year and 50% to 65% after 5 years. For sick sinus syndrome, VVI-pacing proves to be a symptomatic measure, no prognostic importance can be proven. It is not conclusively clarified at present whether physiological pacing modes (AAI, DDD) have any such importance. Pacemaker therapy also has no prognostic importance for bradyarrhythmia. Hemodynamic importance: Numerous hemodynamic studies show that fixed-rate VVI-pacing fails to produce a long-term hemodynamic improvement for either an AV-block or a sick sinus syndrome. In sick sinus syndrome hemodynamic improvement can only be achieved by physiological pacing modes (AAI, DVI, DDD), whereby the increase in cardiac output is between 11% to 30%. For AV-block a long-term hemodynamic improvement can only be obtained by atrial triggered pacing modes (VAT, VDD, DDD); this is higher than the values of fixed-rate VVI-pacing by 7-25% at rest, or 10-40% under exercise. Similar results with improvements of the exercise hemodynamics between 22% and 66% are reported for rate-modulated single-chamber pacing (VVIR) for AV-block. Future trends: In the fourth decade of pacemaker therapy, developments point toward the "smart pacemaker", toward rate-modulated systems with combinations of parameters, toward rate-modulated dual-chamber systems and universal antibradycardiac and antitachycardiac systems.

[Acute and chronic effects of UDCG 115 BS (pimobendan) in patients with advanced myocardial failure]. / Akute und chronische Wirkungen von UDCG 115 BS (Pimobendan) bei Patienten mit fortgeschrittener myokardialer Insuffizienz.

In a double-blind, placebo-controlled cross-over study acute hemodynamic effects of oral UDCG 115 BS (5 and 10 mg) were investigated in myocardial heart failure before (n = 16) and after (n = 13) chronic treatment (4 weeks). Before chronic treatment, UDCG 115 BS induced a similar increase in cardiac index with both doses (5 mg: from 2.4 +/- 0.7 to 3.5 +/- 0.7 l/min/m2, p less than 0.001; 10 mg: from 2.5 +/- 0.6 to 3.6 +/- 0.9 l/min/m2, p less than 0.001). Both right atrial pressure and pulmonary capillary wedge pressure were clearly reduced (p less than 0.001). Heart rate increased slightly only after 5 mg (p less than 0.05). Systemic vascular resistance was reduced (p less than 0.001), whereas mean blood pressure did not change. After chronic treatment (2 x 5 or 2 x 10 mg/d) and cessation of medication for 24 h there was no difference for control hemodynamic values as compared to placebo. Acute hemodynamic effects were considerably attenuated in comparison with the results obtained before chronic treatment. NYHA-classification, however, clearly (p less than 0.05) improved during administration of UDCG 115 BS as compared to placebo. Two patients died on placebo, whereas no patient expired on verum. This might indicate a therapeutic longterm effect of UDCG 115 BS, despite the observed development of partial tolerance.

[Ultra-high dose thrombolytic therapy with streptokinase in peripheral venous thrombosis]. / Ultrahochdosierte Thrombolysetherapie mit Streptokinase bei peripherer Phlebothrombose.

56 patients with deep vein thrombosis (lower limb) and two patients with vena subclavia thrombosis were treated for six hours/day according to an ultrahigh dosage scheme (1,500,000 U/h streptokinase). An average number of three cycles was applied. Complete recanalization could be demonstrated in 23 patients (43%) with lower limb thrombosis, whereas a partial recanalization was demonstrable in 40% (22 patients). A complete thrombolysis could be achieved in one patient with vena subclavia thrombosis. Severe side effects were one intracerebral hemorrhage and one major lung embolism, causing death in both patients. Ultrahigh dosage thrombolysis with streptokinase is an effective therapeutic regimen and is considered to be an alternative to standard fibrinolytic procedures.

Physical movement sensitive pacing: comparison of two "activity"-triggered pacing systems.

The Activitrax (A) and the Sensolog (S) pulse generator units were compared during bench tests and in patients both under ergometric conditions and during daily activities to determine the susceptibility of both systems to external noise. During the bench tests both pacemakers were mounted on a swingboard and subjected to controlled vibrational force. The patients were divided into two groups of 10 patients each, one group with A and the other with S units; the discriminating power of workload changes was examined under treadmill exercise. In six patients of each group the rate behavior of S and A during daily activities was recorded by Holter monitoring. During bench tests, S and A displayed a frequency-selective mode of operation between 2-70 Hz with the greatest sensitivity between 10-50 Hz. In patients, S showed a significantly higher discriminating power to changes in workload during treadmill exercise. According to y = 0.27x + 85.8 (r = 0.92) the relationship between the power and the pacing rate of S was linear, whereas with y = 0.04x + 89.8 (r = 0.2) the pacing rate of A was almost independent of the given power. The susceptibility to external noise occurring while riding in an auto, streetcar or train with rate increases between 7 ppm and 12 ppm did not significantly differ in both systems. Lying prone on the pacemakers produced brief (less than 1 min) rate increases of 38 ppm (S) and 18 ppm (A), respectively.

The combined use of hysteresis and Holter functions improves diagnosis and therapy in patients with sick sinus syndrome.

We used the Holter functions of an implantable pacemaker in 12 patients with sino-atrial disease suffering from Adam-Stokes attacks to analyze the effects of hysteresis programming. The basic pacing rate of 50 ppm combined with a programmed hysteresis value of 10 to 20 ppm led to a drastic reduction in competition between paced and spontaneous beats: the percentage of paced beats decreased from 20.1% without hysteresis to 1.4% using 10 ppm hysteresis and the switches from sense to pace decreased from 2.0% to 0.06%. On the other hand, with hysteresis, no decrease in either the exercise tolerance or general well-being of the patients was observed.

Analysis accuracy and susceptibility to faults of Holter functions in diagnostic pacemakers.

The analysis accuracy and susceptibility to faults of the additional diagnostic functions were tested in 16 patients (eight men, eight woman, average age 61.5 +/- 10.8 years, 14 VVI, 2 AAI) with diagnostic pacemakers (Quintech DPG 921). The average observation period was 19.7 months. With 109 follow-up intervals of an average duration of 87 +/- 39 days, this meant an observation period of 25.9 patient years. A stage-by-stage test structure over several intervals of time was applied in order to validate the data acquired through pacemaker Holter functions by means of control ECGs and mathematical test methods. The only fault to occur in the diagnostic functions was a loss of stored data. This was observed in 10% of the follow-up intervals and was on the average 28% (16%-38%) of the total events. Forty-four percent (7/16) of the pacemakers were affected by this malfunction. Our results show that the diagnostic data are certainly correctly acquired. The clinical value of the diagnostic functions is clearly reduced by this potential loss of data.

First clinical experience with an oxygen saturation controlled pacemaker in man.

This article describes the characteristics of a new implantable pacemaker controlled by right atrial oxygen saturation and reports the first clinical experience in man. During the observation period over 5 months, there was no evidence of malfunction due to tissue growth. The system's reaction to exercise changes proved to be quick (5 s to 17 s); decay times varied depending on the magnitude of the power previously performed. Under various exercise tests, the rate increase was linear to the stress load. Measurements of cardiac output showed the system's hemodynamic feedback and its potential self-optimization of pacing rate.

A new multisensor pacing system using stroke volume, respiratory rate, mixed venous oxygen saturation, and temperature, right atrial pressure, right ventricular pressure, and dP/dt.

A new multisensor pacing device using respiratory rate (RR), stroke volume (SV), oxygen saturation (SO2), temperature (T), right atrial pressure (RAP), right ventricular pressure (RVP) and right ventricular dP/dt, has been developed. It consists of a 7F multisensor catheter and an external pacing unit. It allows simultaneous recording of the input signals and the corresponding data can be compared among the different parameters under identical conditions. Furthermore, several parameters can be combined in such a way as to form a new combination better suitable for rate responsive pacing. The response of each parameter to exercise was studied in 12 healthy volunteers (mean age: 28 years). Exercise testing was carried out using a bicycle ergometer, with workloads up to 200 W. The dynamic characteristics, response and sensitivity to changes of workloads of each parameter were analyzed and compared to one another. SO2 proved to be a quick responding parameter (less than 10 sec) with higher sensitivity in the low exercise range (less than 75 W), T, on the other hand, responded slowly (greater than 30 sec) to exercise changes and had the highest sensitivity in the exercise range beyond 75 W. RR displayed a slow response (greater than 30 sec) and an adequate sensitivity was only found in the upper exercise range (greater than 100 W). SV reacted rapidly to workload changes (less than 10 sec) but showed poor sensitivity at all exercise levels. RAP, RVP and dP/dt displayed quick responses and constantly good sensitivity throughout the workload range. Furthermore, respiratory rate was easily derived from the RAP curve. Special algorithms were developed for each parameter so that pacing rate would reproduce sinus rate behavior. We found that SO2 and all pressure parameter imitated sinus rate response quite well. When using parameter combinations, SO2 and T proved to be superior. Five patients (mean age 68 years) with third degree AV-block were stimulated temporarily using this system. Compared to fixed rate stimulation (VVI 70), exercise performance improved, using SO2 as the input parameter for rate response, by 25% to 50%.

[Holter functions in cardiac pacemakers: expanding diagnostic possibilities and their clinical relevance]. / Holterfunktionen in Herzschrittmachern: Erweiterung diagnostischer Möglichkeiten und ihre klinische Relevanz.

By encompassing diagnostic multifunctions, microprocessor equipped pulse generators represent a marked improvement in the field of diagnosis and treatment. In this sense, bioelectrical data can be recorded over long periods, up to years, making a continuous follow-up possible. Changes in basic cardiac rhythm, pacemaker malfunctions, effect of parameter programming, even the assessment of antiarrhythmic therapy are some information that could be acquired. The screening function is particularly valuable for detecting sporadic arrhythmias and intermittent pacemaker malfunction which would otherwise go undetected. The limitation of this system lies in the fact that it does not render information on morphology and lacks the chronological correlation between recorded events.

[Accuracy of analysis and susceptibility to faults in ECG detection using pacemakers with diagnostic functions]. / Analysegenauigkeit und Störanfälligkeit der EKG-Erkennung bei Schrittmachern mit diagnostischen Funktionen.

The accuracy of analysis and susceptibility to faults of additional diagnostic functions in pacemakers were tested in 16 patients (eight men, eight women, average age 61.5 +/- 10.8 years, 14 VVI, 2 AAI) with diagnostic pacemakers (Quintech DPG 921). The average observation period was 19.7 months. With 109 follow-up intervals this meant an observation period of 25.9 patient-years. A stage-by-stage test structure over several periods of time was used in order to validate the data acquired through pacemaker Holter functions by means of control ECGs and mathematical test methods. The only fault to occur in the diagnostic functions was a loss of stored data. This was observed in 10% of follow-up intervals and was, on average, 28% (16-38%) of the total events. 44% (7/16) of the pacemakers were affected by this malfunction. Our results show that the diagnostic data are certainly correctly acquired. The clinical value of the diagnostic functions is clearly reduced by this potential loss of data.

[Body movement as pacemaker induction value: comparison of 2 activity-triggered pacemakers]. / Körperbewegung als Schrittmacherführungsgrösse: Vergleich zweier Aktivitätsschrittmacher.

This article compares the rate behavior of the activity-triggered pacemakers, the Activitrax (A) and the Sensolog (S), during bench tests as well as in patients under defined ergometric conditions and during every day life with special reference to the susceptibility of both systems to external noise. In the bench tests both pacemakers were mounted on a swingbord and subjected to controlled vibrational force. In the first experiment the frequency, in the second experiment the energy was varied. In two groups, one with S, one with A implanted, each consisting of 10 patients, the discriminating power of workload changes was examined under defined treadmill exercise. Furthermore in 5 patients of each group the rate behavior of S and A under daily life conditions and during common environmental noise was registered using Holter-ECG. In the bench tests S and A displayed a frequency-selective mode of operation between 2 Hz and 70 Hz with the highest sensitivity (resonance frequency) at 10 Hz. In patients, S showed a significantly higher discriminating power to changes of workload under treadmill exercise. According to y = 0.27x + 85.8 (r = 0.92) the relationship between the pacing rate of S and the power was linear whereas with y = 0.04x + 89.8 (r = 0.2) the pacing rate of A was almost independent of the given power. The susceptibility to external noise occurring during riding a car, streetcar or train with rate increases between 7 ppm and 12 ppm did not significantly differ in both systems.(ABSTRACT TRUNCATED AT 250 WORDS)

[Stroke volume, central venous oxygen saturation and blood temperature as control parameters of frequency-adapted pacemaker stimulation]. / Schlagvolumen, zentralvenöse Sauerstoffsättigung und Bluttemperatur als Steuergrössen einer frequenzadaptierten Schrittmacherstimulation.

In order to compare various physiological parameters under identical conditions and to evaluate the "optimal" combination of parameters for triggering a pacing system, a multisensor-catheter of 7 F size was developed. By this catheter placed in the right ventricular cavity, sinus rate (SR), mixed venous oxygen saturation (SO2), temperature (T) and stroke volume (SV) were continuously recorded in 7 volunteers. SR, T, SO2 and SV were analysed for their steady state relationships to workload (P) and for their dynamic characteristics during standardized exercise tests. During exercise the delay times of SR, SO2 and SV were less than 10 sec., whereas that of T was markedly longer ranging from 70 sec. at low exercise levels to 30 sec. at high levels (200 Watts). During recovery delay times of SR, SO2 and SV ranged from 5 to 10 sec., that of T ranged from 20 to 30 sec. The relationship of SR to the workload (0-200 W) performed was linear (r = 0.98), that of T was linear above 50 Watts (r = 0.92), that of SO2 followed an exponential function (r = 0.89). Initial changes of SV were independent (r = 0.02) of the extent of workload. The sensitivity (S = dV/dP) was calculated from the relationship of the parameters (V) measured to the level of exercise performed. SO2 was highly sensitive at the lower range of exercise (less than 75 W), T became constantly sensitive above 50 W, below 50 W the sensitivity of T was continuously decreasing. SR was constantly sensitive over the whole range of exercise (0-200 W), the initial change of SV was not sensitive to the extent of workload.

Physiological pacing: present status and future developments.

With the increasing tendency to implant pacemakers not only for life-threatening bradycardias but also for improving cardiodynamics in patients with bradycardia, it soon became apparent that classical VVI pacing is not truly able to optimize circulatory performance. Experience has shown that with ventricular pacing augmentation of cardiac output takes place only initially but is not maintained on a long-term basis, exercise capacity remains markedly reduced, there is only an unsatisfactory influence on the degree and course of heart failure and, in an occasional patient, cardiac function may even deteriorate as compared to the situation prior to pacing. Because the disappointing hemodynamic effect of fixed rate ventricular stimulation was at least partly due to the "unphysiological" mode of pacing provided by those systems which fail to restore AV synchrony and to increase heart rate with changing metabolic requirements, so called physiological pacemakers were developed. These pacing systems either maintain AV-synchrony and/or reestablish some way to adapt the pacing rate (Table I). This study delineates the hemodynamics of the paced heart with special reference to the role of AV relationship and rate control; it describes the clinical experience with physiological pacing and provides some ideas leading to present and future developments for rate adaptive pacing systems.