[Ethic rounds in intensive care. Possible instrument for a clinical-ethical assessment in intensive care units]

Ethical problems, such as medical end-of-life decisions or withdrawing life-sustaining treatment are viewed as an essential task in intensive care units. This article presents the ethics rounds as an instrument for evaluation of ethical problems in intensive care medicine units. The benchmarks of ethical reflection during the ethics rounds are considerations of ethical theory of principle-oriented medical ethics. Besides organizational aspects and the institutional framework, the role of the ethicist is described. The essential evaluation steps, as a basis of the ethics rounds are presented. In contrast to the clinical ethics consultation, the ethicist in the ethics rounds model is integrated as a member of the ward round team. Therefore ethical problems may be identified and analyzed very early before the conflict escalates. This preventive strategy makes the ethics rounds a helpful instrument in intensive care units.

Continuous venovenous haemofiltration using a citrate buffered substitution fluid

Different methods of regional anticoagulation using citrate in continuous renal replacement therapy have been described in the past. However, these procedures were usually very complex or did not reach modem requirements for effective continuous renal replacement therapy. Furthermore, little is known about long-term acid-base stability and citrate levels during the treatment. We describe a system in which citrate is used both as anticoagulant and as the sole buffer substance in continuous venovenous haemofiltration. Our citrate-containing, calcium-free substitution fluid was used in predilution mode with a constant ratio between blood flow (120 to 150 ml/min) and substitution flow (2400 to 3000 ml/hour). Anticoagulation was limited to the extracorporeal circuit. Twenty patients with acute renal failure on mechanical ventilation were treated, four for eight hours, four for 24 hours and 12 as long they needed continuous renal replacement therapy (9.6 +/- 5.0 days, range 4.0 to 39.3 days). We achieved stable acid-base and electrolyte balance in all patients. We observed no bleeding complications (patient activated clotting time 112.4 +/- 17.1 s, post-filter circuit activated clotting time 270.5 +/- 80.3 s) and achieved appropriate filter life times (48.6 +/- 13.2 h). Predilution, citrate-based substitution fluid provides both anticoagulation within the extracorporeal circuit and control of acid-base balance in critically ill patients at risk of bleeding in acute renal failure. It is easy to apply and safe. Clearance can be varied as long as a constant ratio between blood and substitution flow is maintained.

Signal-averaged P-wave ECG as a marker of atrial electrical instability in patients with right ventricular dysfunction

Severe pulmonary hypertension (PAH) leads to right ventricular dysfunction and is associated with different atrial arrhythmias. In PAH patients, the echocardiographic Tei-index is used for monitoring right heart function. The P-wave signal-averaged ECG (SA-ECG) has been shown to have a potential role in identifying patients at risk of developing paroxysmal atrial fibrillation and those likely to change from paroxysmal to chronic atrial fibrillation. The aim of the present study was to define the correlation of the Tei-Index with parameters of P-wave triggered and bidirectional P-wave SA-ECG. A total of 18 patients (14 men, 4 women) with normal sinus rhythm and a mean age of 67+/-10 years (BMI 27.6+/-5.1 kg/m2) were included into the study. Right ventricular (RV) Tei-index was calculated from the sum of isovolumetric contraction time and relaxation time divided by ejection time. Furthermore, P-wave triggered P-wave signal averaged ECG was performed from an X, Y, and Z lead system. The results show that there was a statistically significant correlation between Tei-index and filtered P-wave duration (r=0.53; P=0.023). Teiindex did not correlate with the root mean square voltage of the last 20 ms of the P wave (r=-0.16; P=0.52). In conclusion, a correlation of RV Tei index with P-wave duration indicates that this echocardiographic measurement is not only a marker of right heart function, but also an indicator of electrical instability that could be useful to detect patients at risk for atrial arrhythmias.

Effects of continuous positive airway pressure on exercise capacity in chronic heart failure patients without sleep apnea

Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea. It is known, that there are beneficial effects on cardiac function, which might be explained by suppression of apnea and specific hemodynamic effects of CPAP. Therefore, CPAP might act as an adjunct therapy in heart failure, even in the absence of sleep apnea. In the present study, 11 patients with congestive heart failure (EF=23.1+/-6.9%) without sleep apnea (AHI 3.0+/-1.2/h) were treated with nocturnal CPAP. Cardiopulmonary exercise testing was performed at baseline and after 8.6 +/-1.3 months. All patients underwent heart catheterization and myocardial biopsy to exclude myocarditis at baseline. Five (46%) of the 11 patients did not complete the study because of poor compliance and irregular use of the CPAP device. Six (54%) of the patients used CPAP regularly (>6 h/night) and completed the study. Cardiopulmonary exercise testing showed an improvement of work load (96+/-36 Watt vs. 112+/-34 Watt; P=0.025) and VO2 peak (1227+/-443 ml vs. 1525+/-470 ml; P=0.01). Oxygen-pulse was increased, although that did not reach significance (11.2+/-4.8 ml/beat vs. 12.6+/-3.9 ml/beat). In conclusion, CPAP might have beneficial effects on exercise capacity in patients with congestive heart failure even in the absence of sleep apnea. Nevertheless, poor compliance seems to be a limiting factor.

Einfluss der kardialen Zirkulation und einer herzwirksamen Medikation auf die Durchblutung der Bauchorgane

Perfusion of the abdomen is determined by cardiac function and circulation. Intestinal ischemia can be caused by Non occlusive bowel ischemia (NOD) that is important in internal as well as surgical intensive care medicine. Cardiac medication can influence perfusion of the bowel: 1) digitalis increases muscular tonus and decreases perfusion regulation b) diuretics lead to hypovolemia, hypotonia and malperfusion, c) antihypertensive medication can cause intraoperative hypotension that demands catecholamines, d) catecholamines can reduce perfusion by pathologic vasoconstriction in the splanchnicus area. Preoperative medication should respect 1) preoperatively taken ACE-inhibitors should be given postoperatively, as they have protective influence on the microcirculation of the bowel, 2) beta-blockers stabilize the myogenic tonus of the abdominal vessels, reduce an overshot of the parasympatheticus and diminish the risk of neurogenic abdominal shock, 3) catecholamines should be used with respect to ischemia of the bowel. Therapy of NOD should be focused on the primary vascular and hemodynamic causes and also take care for bacterial translocation and consecutive sepsis.

Die Pr�diktion des Rezidives von Vorhofflimmern nach elektrischer Kardioversion mittels P-Wellen-Signalmittelungs-EKG

METHOD

A P wave triggered and bidirectional P wave signal averaged ECG was used among 49 patients (35 m/14 w) 24 hours after electrical cardioversion. The measurements were only managed in sinus rhythm. Each patient was followed up for at least 6 months and the mean follow-up was of 9.1 months.

RESULTS

A recurrence of atrial fibrillation was observed in 23 patients (47%) after a mean of 9,2 days (range 2-92 days). There was no difference in organic heart disease or in the use of drugs. The filtered P wave duration (FPD) was longer significantly (136.2 +/- 20.1 vs 119.5 +/- 19.8 ms, p < 0.0001) and the root mean square voltage of the last 20 ms of the P wave (RMS 20) was lower (2.77 +/- 1.10 vs 4.17 +/- 1.43 microV, p < 0.0001) in patients with a recurrence of atrial fibrillation. A cut-off point (COP) of FPD > or = 126 ms and RMS 20 < or = 3.1 microV achieved a specificity of 69%, a sensitivity of 74%, a positive predictive value of 68% and a negative predictive value of 75%.

CONCLUSION

The results of our study suggest that the recurrence of atrial fibrillation after electrical cardioversion can be detected by P wave signal averaged ECG. The occurrence of COP seems to be a high risk factor of the recurrence of atrial fibrillation. The predictive power of the method has to be examined by prospective investigations of a larger patient population and a longer follow-up. The recurrence of atrial fibrillation after cardioversion has a high incidence. In our study, P wave signal averaged ECG was performed one day after successful electrical cardioversion in order to evaluate the utility of this method to predict atrial fibrillation after cardioversion.

Die Pr�diktion des Rezidives von Vorhofflimmern nach elektrischer Kardioversion mit der Chemoreflexsensitivit�t

Patients with paroxysmal atrial fibrillation have a lower chemoreflex sensitivity (CHRS) which is characterized as an autonomic dysfunction. Because of this observation we examined the theory of an autonomic dysfunction as the reason for the reccurrence of atrial fibrilation after electrical cardioversion.

METHOD

We measured the CHRS among 43 patients 24 h after successful electrical cardioversion and the patients were controlled for at least 6 months.

RESULTS

During the six months of follow-up a recurrence was observed in 18 patients with a mean of 8.3 days. There was no difference in organic heart disease or in the use of drugs. Left atrial diameter was not significantly larger in patients with a recurrence. Patients with a recurrence have a significantly lower CHRS than patients with sinus rhythm (2.41 +/- 1.82 vs 5.62 +/- 3.02 ms/mmHg, p < 0.04). The diagnostic value of a CHRS below 3.0 ms/mmHg achieved a specificity of 68%, a sensitivity of 67%, a positive and negative predictive value of 60% and 74%.

CONCLUSIONS

An analysis of CHRS seems to be an appropriate method to predict a recurrence of atrial fibrillation. The predictive power of the method has to be examined by prospective investigations of a larger patient population and a longer follow-up. Patients with paroxysmal atrial fibrillation have a lower chemoreflex sensitivity (CHRS) which is characterized as an autonomic dysfunction. Because of this observation we examined the theory of an autonomic dysfunction as the reason for the recurrence of atrial fibrillation after electrical cardioversion.

Chemoreflexsensitivity among patients with paroxysmal atrial fibrillation

Atrial fibrillation is the most common cardiac arrhythmia with typical complications of thromboembolisms. The autonomic nervous system is an important factor for the initiation of arrhythmias. A vagally or adrenergically hyperfunction could cause the initiation of paroxysmal atrial fibrillation (PAF).

METHOD

We measured the chemoreflexsensitivity (CHRS) among 110 patients to determine a disturbed autonomic function as risk factor for PAF. We examined 45 patients with PAF (group A), 45 patients with sinus rhythm (group B) and 20 young volunteers (group C). The ratio between the difference of RR intervals in ECG and venous pO(2) was measured for the determination of CHRS. The margin of the CHRS was 3 ms/mmHg.

RESULTS

Patients of group A had a significantly lower CHRS compared to group B (1.56+/-1.46 vs 6.29+/-3.71 ms/mmHg, p<0.0008) or group C (1.56+/-1.46 vs 6.35+/-4.29 ms/ mmHg, p<0.0003). A significant difference between group B and C could not be observed (6.29+/-3.71 vs. 6.35+/-4.29 ms/mmHg, p = n.s.). A specificity of 74% and a sensitivity of 71% was achieved for identifying patients with PAF by using a margin of 3 ms/mmHg for the CHRS.

CONCLUSIONS

An analysis of CHRS seems to be an appropriate method to demonstrate a neurovegetative imbalance which might be one possible trigger mechanism of PAF. The predictive power has to be examined by prospective investigations of a larger patient population.

[Detection of atrial late potentials with P wave signal averaged electrocardiogram among patients with paroxysmal atrial fibrillation]

The analysis of the QRS-complex with signal averaged ECG (SAECG) has been evaluated for patients affected by ventricular tachycardia for a long time. A longer filtered QRS-complex was a marker of a slower ventricular conduction velocity and reentry tachycardia. This method was modified for an analysis of the P wave (P-SAECG). Different filter methods were evaluated for the analysis of atrial late potentials.

METHOD

We measured the bidirectional P wave signal averaged ECG of 45 consecutive patients with (group A) and without (group B) paroxysmal atrial fibrillation (PAF) and 15 young volunteers without a cardiac disease (group C).

RESULTS

As a result patients with PAF had a significantly lower root mean square voltage of the last 20 ms (RMS 20) (2.59 +/- 0.89) vs 4.08 +/- 1.45 microV, p < 0.0003) and a significantly longer filtered P wave duration (FPD) than patients of the control collective (139.2 +/- 17.5 vs 115.1 +/- 17.7 ms, p < 0.0001) and the young volunteers (3.44 +/- 0.95 microV, p < 0.0001/101.9 +/- 14.2 ms, p < 0.009). Furthermore we found an age-dependent relationship of FPD between group B and C (115.1 +/- 17.7 vs 101.9 +/- 14.2 ms, p < 0.05) but not an age-dependent relationship of the RMS 20 (4.08 +/- 1.45 vs 3.44 +/- 0.95 microV, p = n.s.). A specificity of 80% and a sensitivity of 78% was achieved for identifying patients with atrial fibrillation by using a definition of atrial late potentials as FPD > 120 ms and a RMS 20 < 3.5 microV.

CONCLUSIONS

The analysis of the P-SAECG can be used as a non-invasive method for identifying atrial late potentials. Atrial late potentials might be a reason for PAF. The predictive power of atrial late potentials has to be examined by prospective investigations of a larger patient population.

[Lipoid pneumonia following attempted suicide by intravenous injection of lamp oil]

BACKGROUND

Pneumonic complications after intoxication with mineral oils have been described before in the contents of accidental aspiration and oral ingestion. However, intoxication following an intravenous injection leading to a lipoid pneumonia after an attempted suicide is a rare finding.

CASE REPORT

A case report is presented of an attempted suicide by intravenously self-injection of 20 ml lamp oil (liquid paraffin). Immediately after injection the patient suffered from dry coughing which changed in the course of the next hours into a productive cough with white thick mucous sputum accompanied by hemoptysis. Additionally, he developed a mild disseminated intravascular coagulation with a fall of thrombocytes, an INR of 1.6 and a rise of D-dimeres. Under a therapy with hydrocortisone, ascorbic acid, ambroxol, acetylcysteine, heparin, antibiotics and oxygen, the patient improved without the need of mechanical ventilation. Initially seen signs of right heart dilatation diminished 3 days after onset of therapy. Apart from pulmonal manifestation no relevant organ damage was observed. The patient was discharged from the intensive care unit 9 days after intoxication and was submitted to psychiatric therapy.

CONCLUSION

Lipoid pneumonia caused by intoxication with a mineral oil is a severe disease, whereas in the presented case a relative bland course of the disease has been seen. The employed therapy in this patient might be encouraging for a comparable treatment of pneumological complications resulting from similar clinical pictures.

[14-year experience with implantable cardioverter/defibrillators: determination of prognosis and discharge behavior]

BACKGROUND

The treatment of life threatening ventricular arrhythmias with implantable cardioverter/defibrillators (ICD) has become the therapy of choice; the survival benefit of ICD treatment compared to drug therapy in patients with aborted sudden cardiac death (SCD) and hemodynamically unstable ventricular tachycardia has been proven. In addition for the primary prevention of SCD in high risk patients, ICD therapy is gaining growing acceptance.

PATIENTS AND METHODS

We analyzed the long-term follow-up of 274 consecutive patients (211 male, 63 female, age 59 +/- 12 years, left ventricular ejection fraction 39 +/- 15%) provided with an ICD between 1984 and 1998. The aim of the study was to ascertain the survival rate in different subgroups and to discover determining factors of ICD discharge and prognosis.

RESULTS

Long-term survival probability at 10 resp. 14 years was 84 resp. 65% for the total collective, and the freedom of event probability (neither shocks nor antitachycardiac pacing from the ICD) to 28% each. The risk to die from SCD was below 3% over time. The most pronounced differences regarding prognosis ensued from dividing the collective into heart insufficiency stages. Thus in NYHA class I and II versus III and IV, the cumulative event rate was 61% vs 82% at 5 years, and survival rate amounted to 94 vs 63% at 5 years and 87% vs 30% at 14 years (p < 0.001). Calculating the relative benefit of ICD therapy survival benefit provided by the ICD was shown to decrease significantly after 5 years for patients in NYHA class III/IV, while it increased progressively for patients in NYHA class I/II up to 10 years. Additional determinants of prognosis and ICD discharge rate were identified left ventricular ejection fraction, age and tendency for the basic cardiac disease, however neither the result of electrophysiological testing nor the results of non-invasive risk stratification. In patients with ischemic heart disease, revascularization procedures improved prognosis only in tendency, while the effect of ICD therapy was significant. In patients with the non-obstructive form of hypertrophic cardiomyopathy ICD, discharges occurred in about 50% of patients; in contrast patients with surgical myectomy for obstructive cardiomyopathy showed no events during follow-up. In patients with chronic inflammatory heart disease and normal left ventricular function (LVF), a very low event rate was expected if patients were treated by immunosuppressive drugs. Patients with dilated cardiomyopathy did not differ from patients with ischemic heart disease with respect to prognosis and ICD discharge rate.

CONCLUSION

Significant determinants of prognosis and ICD discharge rate are left ventricular function, age and with limitations the basic cardiac disease. In contrast to patients with better LVF relative survival benefit decreases significantly after 5 years in patients with a worse LVF. Patients with aborted SCD and preserved LVF experience half the ICD discharges compared to patients with poor LVF and gain at the same time a normalization of life expectancy. Causative treatment of the basic disease has an impact on the overall prognosis and event rate, but should in general not influence the decision for IDC implantation in high risk patients.

[Arrhythmia risk in left ventricular hypertrophy]

The incidence of supraventricular and ventricular arrhythmias in patients with arterial hypertension is up to 96% and is about 10 times higher than in normotensives. Predictors for an increased ventricular arrhythmogenic risk are left ventricular hypertrophy (LVH), impaired left ventricular function with enlarged end diastolic and end diastolic volumes as well as late potentials which in case of LVH increase from a 7% to 18% incidence. Especially the Simson criteria fQRS and RMS seem to characterize patients at risk. In addition a longer duration of hypertension in conjunction with a higher muscle mass index and a larger amount of couplets and non-sustained ventricular tachycardias, documented by Holter recording, are determinants of life threatening arrhythmias. In addition, an increased ventricular vulnerability in electrophysiological study significantly depends on left ventricular hypertrophy. Regression of LVH goes along with a decreased rate of ventricular extrasystoles. We therefore hypothesize that by pharmacological regression of hypertrophy the prevalence of complex arrhythmias decreases.

[Heart rate variability and chemoreflex sensitivity. Proved and new methods in risk prediction of malignant arrhythmias]

For the analysis of a disturbed autonomic function as a risk predictor for ventricular tachyarrhythmias, tonic and phasic procedures are available. The heart rate variability as a tonic procedure shows significant differences between patients with an increased risk of malignant arrhythmias and patients without increased risk. This can be demonstrated in patients with survived myocardial infarction, dilated cardiomyopathy and congestive heart failure. But the positive predictive value amounts only to about 50%. The chemoreflex sensitivity as a new phasic method represents a new possibility for the evaluation of a dysfunction of autonomic reflex arches. It is reduced due to a decreased left ventricular function and increasing age. Furthermore, it shows significant differences between patients with ventricular arrhythmias and patients without. The predictive accuracy concerning malignant ventricular arrhythmias in a population of 60 patients in the chronic postinfarction stadium amounts to 55%, the relative risk to 7.6. Thus, this method shows a high predictive power, but more investigations in larger patient cohorts are necessary to corroborate these results.

[Impact of a percutaneous transluminal coronary angioplasty on the prevalence of ventricular late potentials among patients with survived myocardial infarction]

The aim of the study was to evaluate whether a causal antiischemic intervention as percutaneous transluminal coronary angioplasty (PTCA) leads to a reduction of ventricular late potentials in the chronic post myocardial infarction period. In 24 patients, signal-averaged electrocardiograms (SAECG) for two groups were recorded for the analysis of ventricular late potentials (LP) before and after 6.0+/-4.2 months (group A, with PTCA) and 6.2+/-5.2 months, respectively (group B, conservative therapy). All patients presented prior myocardial infarction. LP were defined present if two of the three time domain criteria were met. In the whole study group, LP were positive in 73%. In group A, a PTCA was performed one month after the initial SAECG measurement. In group A, the presence of ventricular late potentials was significantly reduced (64% vs. 18%), whereas in group B only a slight decline of late potentials could be observed (85% vs. 62%). The parameters of the signal averaged ECG varied significantly in group A before and after PTCA (QRS 113.04+/-13.65 vs. 100.55+/-6.97 ms (p<0.05), RMS 24.04+/-24.13 vs. 35.39+/-16.89 muV (p=n.s.), LAS 41.23+/-13.27 vs. 29.68+/-6.47 ms (p<0.05)). The results in group B were not altered significantly.In conclusion, these results show that a PTCA of the infarct-related artery can lead to a reduction in ventricular late potentials in patients with significant coronary artery disease, who are also in the chronic post myocardial infarction period. Whether it is possible to improve the prognosis of these patients has also to be shown in future studies.

[Formation, therapy and prevention of false aneurysm of the femoral artery following diagnostic and interventional heart catheterization]

OBJECTIVE

As pseudoaneurysm of the femoral artery after catheter introduction is a frequent complication, its causes and therapeutic options were investigated in a large patient collective.

PATIENTS AND METHODS

In a prospective study with colour-Doppler duplex sonography of 6928 patients after diagnostic and of 3764 after interventional cardiac catheterisation, pseudoaneurysms were diagnosed in 80 patients (0.75%), 46 after diagnostic (0.66%) and 34 after interventional (0.9%) catheterisation.

RESULTS

The incidence was higher in women than men (1.33% vs 0.58%; P < 0.05). Anticoagulation after sheath removal was the leading risk factor (n = 55, 68.8%), especially after interventional coronary intervention 85.3 vs 56.5%, P < 0.05). Local compression under duplex sonography monitoring was undertaken in 69 patients (86.3%), achieving aneurysmal obliteration in 53 (76.8%). Spontaneous thrombosis occurred in 15 of the remaining 27 patients, and surgical closure became necessary in 12.

CONCLUSIONS

These data indicate a risk profile for the occurrence of pseudoaneurysm after cardiac catheterisation which can be dealt with by preventive measures. Local compression under duplex sonographic monitoring was the treatment of choice with a high success rate and low incidence of complications.

[Prognostically relevant parameters in patients with coronary heart disease, arterial hypertension and sleep apnea disorders]

Patients with untreated sleep apnea syndrome have a higher cardiovascular mortality. It is not known which mechanisms lead to this increase in mortality and whether it is independent from the often associated coronary heart disease and systemic hypertension. In 48 consecutive patients with coronary heart disease confirmed by angiography, exercise-ECG, Holter-ECG, echocardiography, spirometric tests, analysis of ventricular late potentials, heart rate variability and a test for sleep-disordered breathing with a screening device were performed. Seventeen patients showed disordered breathing during sleep (obstructive sleep apnea) with a desaturation index of > or = 10 (mean desaturation index 17.3 +/- 9.3 vs. 2.6 +/- 3.1 in the patients without sleep-disordered breathing). There are no significant differences in age (58.9 +/- 6.1 vs. 59.7 +/- 7.6 years), body-mass-index (28.6 +/- 3.7 vs. 27.7 +/- 3.3 kg/m2), left ventricular ejection fraction (57.2 +/- 13.6 vs. 64.0 +/- 14.6%), forced expiratory volume in 1 second/vital capacity 95.4 +/- 13.9 vs. 92.9 +/- 11.2% predicted, heart rate variability (standard deviation of the RR-intervals 39.4 +/- 29.4 vs. 37.2 +/- 17.0 ms), the frequency of premature ventricular beats over 24 h and at night, the frequency of multivessel disease (71 vs. 68%), additional hypertension 53 vs. 48%), status postmyocardial infarction (47 vs. 48%) and positive late potential analysis (24 vs. 13%). There were no ST segment depressions during the night. Patients with coronary heart disease and mild sleep-disordered breathing show no significant differences in the investigated parameters compared with patients without obstructive sleep apnea or sleep-disordered breathing.

[Immunosuppressive therapy for effective suppression of life threatening ventricular tachyarrhythmias in chronic myocarditis]

Chronic myocarditis predisposes to the occurrence of spontaneous ventricular arrhythmias. It is not known if an immunosuppressive treatment-as a casual therapy-leads to arrhythmia suppression. In the present study, 12 patients (four female, eight male, mean age 53 +/- 15 years) with a mean left-ventricular ejection fraction of 52 +/- 19% were included. After exclusion of coronary macroangiopathy, the presence of chronic myocarditis was demonstrated by immunohistological evaluation of right-ventricular biopsies taking the number of specific lymphocytes (CD 2-8), of activated macrophages and the degree of HLA-expression on interstitial and endothelial cells as a basis. Seven patients had a successful resuscitation due to ventricular fibrillation in their case history, three patients presented sustained monomorphic ventricular tachycardia and two syncopes with inducible tachyarrhythmias. As a "conventional" therapy ten patients received antiarrhythmic drugs and four patients an implantable cardioverter/defibrillator. After confirmation of the diagnosis by a second biopsy after 3 months, all patients underwent an immunosuppressive therapy with methylprednisolone. The initial dose of 1 mg/kg body weight was reduced by 20 mg each every 2 weeks, until a maintenance dosage of 8-12 mg/day was achieved. If the control study after 6 months still gave a positive result, a combined therapy with azathioprine, 100-150 mg/day, was carried out for a further 6 months. In nine patients (75%), the control biopsy became negative, in three patients (25%), the biopsy remained to be positive. In the group presenting negative biopsies, no tachyarrhythmia relapse occurred within a follow-up period of 49 +/- 13 months, while in the group with positive biopsies, relapses occurred in two of three patients. Complete suppression during EPS after therapy was achieved in 50% of the patients who were inducible before therapy. In addition to lymphocyte infiltration, particularly HLA expression on endothelial and interstitial cells was significantly reduced; left-ventricular ejection fraction was improved only in tendency, while left-ventricular filling pressure decreased significantly. In summary, in patients with chronic myocarditis and malignant ventricular arrhythmias, a high-dose immunosuppressive long-term therapy results in the significant reduction of inflammatory infiltrations in about 75% of the cases and, at the same time, in the effective suppression of arrhythmias.

[Chemoreflex and baroreflex sensitivity in patients with survived sudden cardiac death]

INTRODUCTION

To evaluate patients with an increased risk of sudden cardiac death the analysis of ventricular late potentials, heart rate variability and baroreflexsensitivity is helpful. However, the prediction of malignant arrhythmic events cannot be performed with sufficient accuracy. For a better identification of high risk patients other methods are necessary. In this study the impact of the chemoreflexsensitivity for the prediction of ventricular tachyarrhythmias was investigated.

METHODS

Out of 44 patients included in the study, 23 were survivors of sudden cardiac death (SCD). Seven patients suffered from sustained monomorphic ventricular tachycardias, 14 had no arrhythmic events in their prior history. For the investigation of the baroreflexsensitivity (BRS) systolic blood pressure was augmented by Norfenefrin (Novadral) and the resulting increase of RR-intervals was measured in the surface-ECG. For determination of the chemoreflexsensitivity (ChRS) the ratio of the RR-interval-shift and the blood pressure shift during a 5-min inhalation of oxygen with a nose mask was formed.

RESULTS

Patients with aborted SCD showed significantly decreased values for the ChRS compared to those patients without an arrhythmic event in their prior history (2.49 +/- 1.86 vs. 6.75 +/- 6.79 mm Hg, p < 0.001). In contrast, for the BRS no significant differences could be found (5.23 +/- 3.95 vs. 5.34 +/- 3.10 mm Hg, p = n.s.). Patients with aborted sudden cardiac death and inducible tachyarrhythmias during the electrophysiologic study showed significantly lower values of BRS and ChRS compared to patients without inducibility.

CONCLUSION

As a new method for identification of patients with an increased risk of sudden cardiac death the analysis of chemoreflexsensitivity seems feasible and indicates an increased arrhythmic risk with a high sensitivity. The predictive impact has to be corroborated in larger patient collectives by prospect studies.