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C Perings

Publications and source records attributed to C Perings.

At least 19 recordsLinked to original sources
PubMed2001

[Can pathological left ventricular hypertrophy in arterial hypertension be distinguished from physiological hypertrophy caused by sports?].

BACKGROUND AND OBJECTIVE: Patients with hypertensive heart disease and left ventricular hypertrophy demonstrate impaired left ventricular diastolic filling. Aim of this study was to find out if physiological left ventricular hypertrophy induced by endurance training causes abnormal left ventricular systolic and diastolic filling. METHODS: We examined 42 athletes with left ventricular hypertrophy due to endurance training (aged 25 +/- 7 years), 31 patients with left ventricular hypertrophy due to hypertensive heart disease (aged 28 +/- 6 years) and 20 untrained, healthy subjects (controls, aged 26 +/- 8 years) by conventional echocardiography and calculated left ventricular muscle mass and fractional shortening. In addition the following Doppler-echocardiographic parameters were measured: maximal early and late velocity of diastolic filling, ratio of maximal early and late velocity of diastolic filling, acceleration and deceleration time and isovolumetric relaxation time. RESULTS: All three study groups showed normal fractional shortening. Conventional echocardiography revealed a higher left ventricular muscle mass in the two study groups as compared to the controls (controls: 119 +/- 12 g, athletes: 225 +/- 18 g*; hypertensive patients: 216 +/- 16 g*; * p < 0.01 versus controls). In the athletes with physiological left ventricular hypertrophy a normal left ventricular diastolic filling pattern was documented (VE: 0.64 +/- 0.1 m/s; VA: 0.51 +/- 0.2 m/s). In hypertensive heart disease a diastolic dysfunction in terms of a delayed relaxation pattern with a decrease of maximal early velocity of diastolic filling (VE: 0.45 +/- 0.09 m/s) and a compensatory increase of the maximal late velocity of diastolic filling (VA: 0.54 +/- 0.1 m/s) was demonstrated. CONCLUSION: In pathological left ventricular hypertrophy due to hypertensive heart disease a pathological diastolic filling pattern was documented. In athletes with physiological left ventricular hypertrophy a normal left ventricular diastolic filling pattern was revealed. Thus Doppler-echocardiographic parameters of left ventricular diastolic function can be of diagnostic importance for discriminating between pathological and physiological left ventricular hypertrophy.

Adolescent↗
PubMed2001

[Determination of right ventricular ejection fraction by thermodilution catheter technique during exercise: a comparison with radionuclide ventriculography].

Since the development of a Swan-Ganz Thermodilution Ejection Fraction Catheter, several studies have been published which compare this technique for obtaining right ventricular ejection fraction (RVEFTD) with alternative methods. However, the reliability of RVEFTD measurements under exercise conditions remains undetermined. Therefore, the aim of the present study was to evaluate RVEFTD with the Gated Blood Pool method (RVEFGBP) under exercise conditions. Twenty patients with different cardiac diseases (coronary artery disease, valvular incompetence, cardiomyopathy) underwent right heart catheterization, including RVEFTD and simultaneous RVEFGBP determination at rest and during supine bicycle exercise. Cardiac index at rest-/exercise was 2.9 +/- 0.8/5.7 +/- 2.2 l/min/m2, mean pulmonary artery pressure was 15 +/- 5/25 +/- 8 mmHg, RVEFTD was 38 +/- 6/41 +/- 11% and RVEFRNV was 39 +/- 6/43 +/- 8%. Linear regression analysis showed a significant correlation between RVEFTD and RVEFGBP at rest (r = 0.72, p < or = 0.0005) and during exercise (r = 0.72, p < or = 0.0005). It is concluded that the Thermodilution Ejection Fraction Catheter is a useful device for reliable, repetitive and safe RVEF measurements, not only at rest but also under exercise conditions. This is clinically important, because RVEF, as a sensitive parameter of primary or secondary right ventricular dysfunction, can be determined in the course of standard right heart catheterization.

Adult↗
PubMed2001

T wave alternans and ventricular arrhythmias in arterial hypertension.

Patients with a positive microvolt-level T wave alternans (TWA) are characterized by an increased risk of ventricular tachyarrhythmias. Arterial hypertension leads to an increase of sudden cardiac death risk, particularly if left ventricular hypertrophy is present. The aim of this study was to investigate the value of TWA in patients with arterial hypertension. Fifty-one consecutive patients were included in the study. TWA analysis was performed with patients sitting on a bicycle ergometer and exercising with a gradual increase of workload to maintain a heart rate of at least 105/min. After recording 254 consecutive low-noise-level heartbeats, the exercise test was stopped. The ECG signals were digitally processed by a spectral analysis method. The magnitude of TWA was measured at a frequency of 0.5 cycle per beat. A TWA was defined as positive if the ratio between TWA and noise level was >3.0 and the amplitude of the TWA was >1.8 microV. Eight of the 51 patients (16%) showed a positive TWA. If left ventricular hypertrophy was present, the prevalence of TWA was higher (33.3% versus 8.3%; P:<0.05). Sensitivity concerning a previous arrhythmic event was 73%, and specificity was 100%. The alternans ratio was significantly higher in patients with a previous event (39.3+/-62.3 versus 2.4+/-4.6; P:<0.001), as was the cumulative alternans voltage (4.7+/-4.1 versus 1.6+/-1.9 microV; P:<0.001). In 16 patients invasively investigated by an electrophysiological study, a significant correlation between inducibility of tachyarrhythmias and a positive TWA result was found (Spearman R:=0.36, P:=0.01). We conclude that the arrhythmic risk of patients with arterial hypertension is markedly increased if microvolt-level TWA is present. The prevalence of TWA is higher in patients with left ventricular hypertrophy.

Adult↗
PubMed2001

Adenosine in the noninvasive diagnosis of dual AV nodal conduction: use as a follow-up parameter after slow pathway ablation in AVNRT.

OBJECTIVE: The aim of this study was to evaluate if administration of adenosine during sinus rhythm to patients with PSVT of unknown mechanism is capable to detect dual AV nodal conduction and furthermore to evaluate this diagnostic parameter as a controlling test after slow pathway ablation in AVNRT. METHODS AND RESULTS: Before electrophysiological study 35 consecutive patients with PSVT were given adenosine during sinus rhythm. After radiofrequency ablation the adenosine test was repeated in a subset of 19 patients. The electrophysiological study revealed 19 patients (54%) with typical AVNRT (study group), 10 (29%) with atrioventricular reentry tachycardia (AVRT), 4 (11%) with ectopic atrial tachycardia (EAT) and 2 patients (6%) with inducible atrial flutter (AF) (control group). We observed a sudden increment of the PQ interval of more than 50 msec between two consecutive beats in 15 of 19 patients (79%) in the study group (75+/-35 msec) and in 2 patients (1 with EAT, AF) of the control group (19+/-12 msec) (p<0.001). After slow pathway radiofrequency ablation the sudden increment of PQ interval persisted in 4 of 12 patients (33%) of the study group. Three of these 4 patients had a relapse of AVNRT during a follow-up of 3 months. CONCLUSION: The administration of adenosine during sinus rhythm is an excellent noninvasive diagnostic test for identifying dual AV nodal conduction and additionally for verifying radiofrequency ablation results in patients with AVNRT.

Adenosine↗
PubMed2000

Optimal method to achieve consistently low defibrillation energy requirements.

Reduction of the defibrillation energy requirement offers the opportunity to decrease implantable cardioverter defibrillator (ICD) size and to increase device longevity. Therefore, the purpose of this prospective study was to obtain confirmed defibrillation thresholds (DFTs) of < or = 15 J in each patient with an endocardial dual-coil lead system incorporating an active pectoral pulse generator (TRIAD lead system: RV- --> SVC+ + CAN+). According to our previous clinical and experimental studies, we tried to lower DFTs that were > 15 J by repositioning the distal coil of the endocardial lead system in the right ventricle. A total of 190 consecutive patients requiring ICDs for ventricular fibrillation and/or recurrent ventricular tachycardia were investigated at the time of ICD implantation (42 women, 148 men; mean age 61.9 +/- 12.0 years; mean left ventricular ejection fraction 42.7 +/- 16.6%). Coronary artery disease was present in 139 patients; nonischemic dilated cardiomyopathy in 34 patients; and other etiologies in 17 patients; 47 patients had undergone previous cardiac surgery. Regardless of optimal pacing and sensing parameters, for patients having DFTs > 15, we repositioned the distal coil of the endocardial lead system toward the intraventricular septum to include this part of both ventricles within the electrical defibrillating field. In 177 of 190 patients, induced ventricular fibrillation was successfully terminated with < or = 15 J (group I) using the initial lead position. Repositioning of the endocardial lead was necessary in 13 patients whose DFT(plus) (DFT(plus) = second additional success at lowest energy level) were > 15 J (group II). In all patients, repositioning was successful within a 15 J energy level (100% success). The mean DFT(plus) was 7.3 +/- 3.5 J (group I) and 11.0 +/- 4.5 J (group II; p<0.005). The mean DFT(plus) of all patients enrolled in the study was 7.6 +/- 3.7 J (range: 2 to 15 J). In 87% of all patients, DFT(plus) of < or = 10 J was achieved. Repositioning of the endocardial lead in the right ventricle is a simple and effective method to reduce intraoperative high DFTs. As a result of this procedure, ICDs with a 20 J output should be sufficient for the vast majority (87%) of our patients. Furthermore, we were able to avoid additional subcutaneous or epicardial electrodes in all patients.

Aged↗
PubMed2000

Chemoreflexsensitivity in patients with survived sudden cardiac arrest and prior myocardial infarction.

For evaluation of patients with an increased risk of sudden cardiac death, the analyses of ventricular late potentials, heart rate variability, and baroreflexsensitivity are helpful. But so far, the prediction of a malignant arrhythmic event is not possible with sufficient accuracy. For a better risk stratification other methods are necessary. In this study the importance of the ChRS for the identification of patients at risk for ventricular tachyarrhythmic events should be investigated. Of 41 patients included in the study, 26 were survivors of sudden cardiac arrest. Fifteen patients were not resuscitated, of whom 6 patients had documented monomorphic ventricular tachycardia and 9 had no ventricular tachyarrhythmias in their prior history. All patients had a history of an old myocardial infarction (> 1 year ago). For determination of the ChRS the ratio between the difference of the RR intervals in the ECG and the venous pO2 before and after a 5-minute oxygen inhalation via a nose mask was measured (ms/mmHg). The 26 patients with survived sudden cardiac death showed a significantly decreased ChRS compared to those patients without a tachyarrhythmic event (1.74 +/- 1.02 vs 6.97 +/- 7.14 ms/mmHg, P < 0.0001). The sensitivity concerning a survived sudden cardiac death amounted to 88% for a ChRS below 3.0 ms/mmHg. During a 12-month follow-up period, the ChRS was significantly different between patients with and without an arrhythmic event (1.64 +/- 1.06 vs 4.82 +/- 5.83 ms/mmHg, P < 0.01). As a further method for evaluation of patients with increased risk of sudden cardiac death after myocardial infarction the analysis of ChRS seems to be suitable and predicts arrhythmias possibly more sensitive than other tests of neurovegetative imbalance. The predictive importance has to be examined by prospective investigations in larger patient populations.

Aged↗
PubMed2000

T wave alternans as a risk predictor in patients with cardiomyopathy and mild-to-moderate heart failure.

The analysis of t wave alternans (TWA) was introduced to identify patients with an increased risk of ventricular tachyarrhythmias. The inducibility of ventricular tachyarrhythmias and the spontaneous arrhythmic events are correlated with a positive TWA in patients with a reduced left ventricular ejection fraction and survived myocardial infarction. In contrast, this study is the first to investigate the correlation of a survived sudden cardiac death and TWA in patients without coronary heart disease and only slightly decreased left ventricular function. Sixty patients were included in the study. The TWA analysis was performed using the Cambridge Heart system (CH2000). Patients were sitting on a bicycle ergometer and exercised with a gradual increase of workload to maintain a heart rate of at least 105 beats/min. The exercise test was stopped after recording 254 consecutive low noise level heart beats. The electrocardiographic signals were digitally processed using a spectral analysis method. The magnitude of TWA was measured at a frequency of 0.5 cycles/beat. A TWA was defined as positive if the ratio between TWA and noise level was > 3.0 and the amplitude of the TWA was > 1.8 microV. Twelve (20%) of the included 60 patients showed a positive TWA. The sensitivity concerning a previous arrhythmic event amounted to 65%, the specificity up to 98%, respectively. The alternans ratio was significantly higher in patients with a previous event (30.3 +/- 53.2 vs 2.9 +/- 5.9, P < 0.001) and cumulative alternans voltage (4.67 +/- 3.55 vs 1.75 +/- 1.88 microV, P < 0.001). In 19 patients, invasively investigated by an electrophysiological study, a significant correlation between inducibility of tachyarrhythmias and a positive TWA result was found (Spearman R = 0.51, P = 0.01). In conclusion, the TWA analysis seems to identify patients with nonischemic cardiomyopathy who are at an increased risk of ventricular tachyarrhythmias.

Adult↗
PubMed2000

[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.

Aged↗
PubMed2000

[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.

Adult↗
PubMed2000

[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.

Adult↗
PubMed1999

Congenital asplenia detected in a 60 year old patient with septicemia.

A 60 year-old female who had never been seriously ill, was brought to the emergency ward after she had been found somnolent at home. She developed renal failure, meningitis, respiratory distress and disseminated intravascular coagulation. Overwhelming septicemia was evident, and streptococcus pneumoniae was isolated from blood and cerebrospinal fluid. Surprisingly, peripheral blood smears showed numerous Howell-Jolly-bodies, indicating severe impairment of splenic function. On abdominal ultrasound, CT-scan, and scintigraphy no spleen could be detected. There was no history of abdominal surgery. Apparently, congenital asplenia, which was not noticed until the age of 60, was responsible for the patient's life-threatening septicemia. We suggest that, in cases of severe septicemia, the examination of a blood smear is useful to detect functional (or congenital) asplenia.

Bacteremia↗
PubMed1999

Hemodynamic effects of celiprolol in patients with ischemic and non-ischemic cardiomyopathy.

In this study, the effect of celiprolol (beta-1-antagonist with beta-2-agonistic activity) on hemodynamic and electrocardiographic parameters of patients with congestive heart failure due to ischemic (iCMP) and non-ischemic (niCMP) origin should be evaluated. Sixteen patients were included into the study, nine with iCMP, seven with niCMP. All patients were investigated by radionuclide ventriculography (99mTc), right heart floating catheterization, and late potential analysis and measurement of heart rate variability. All patients received 200 mg celiprolol after a 3-day period of 100 mg celiprolol/day. All patients showed, after a follow-up period of 3 months, a significant improvement of the left ventricular ejection fraction. The changes of hemodynamic parameters were more pronounced in patients with niCMP. Heart rate did not decrease in patients with niCMP. A 3-month therapy with celiprolol as an additional therapy to a preexisting heart failure therapy leads to a significant improvement of the ejection fraction in patients with congestive heart failure. Patients with niCMP seemed to profit more from this additional beta-blocking therapy.

Adrenergic beta-Agonists↗
PubMed1999

[Large pseudoaneurysm of the left ventricle after posterolateral wall infarct].

Pseudoaneurysms of the left ventricle are rare complications after acute myocardial infarction. We report on a 69 year old patient with a large false aneurysm located in the posterolateral ventricular wall. It became clinically apparent during an episode of severe left heart failure. Echocardiography and left ventriculography allowed an accurate determination of localization and dimension of the pseudoaneurysm; coronary angiography revealed a proximal occlusion of the left circumflex coronary artery. Because of the high risk of rupture, a rapid surgical repair of the false aneurysm was indicated.

Aged↗
PubMed1999

[Early decrease in diastolic function in young type I diabetic patients as an initial manifestation of diabetic cardiomyopathy].

INTRODUCTION: The early determination of the myocardial manifestation is of considerable importance, since the prognosis of patients (P) with insulin dependent diabetes mellitus (IDDM) is generally masked by secondary cardiac complications. The aim of this study was to investigate whether young, asymptomatic P with IDDM and persisting normal systolic left ventricular (LV) function already show a diastolic LV dysfunction. METHODS: An echocardiographical examination of 92 IDDM patients (age: 25 +/- 4 years) without known cardiac disease and of 50 control persons (C) of similar ages was carried out. P with a cardiac disease or long-term diabetic syndrome were excluded. Using M-mode echocardiography, morphological parameters and systolic time-intervals (fractional shortening; ejection fraction) were determined. Doppler indices were then measured: maximal early and late diastolic flow velocity (VE; VA), E/A ratio, acceleration and deceleration time (DT), isovolumetric relaxation time (IVRT). RESULTS: Although the left atrial and left ventricular dimensions, as well as the systolic functional parameters of all P with IDDM were normal, they showed a diastolic dysfunction with a reduction of the early diastolic filling (VE; 0.54 +/- 0.07 m/s vs 0.72 +/- 0.04 m/s; p < 0.01) and the E/A ratio (0.9 +/- 0.15 vs 1.99 +/- 0.22; p < 0.01), an increase in the atrial filling (VA; 0.76 +/- 0.05 m/s vs 0.39 +/- 0.04 m/s, p < 0.01), an extension of the IVRT (129 +/- 23 ms vs 78 +/- 6 ms, p < 0.01), and an increased DT (248 +/- 27 ms vs 188 +/- 8 ms, p < 0.01). CONCLUSION: Even young P with IDDM, with a normal systolic ventricular function, suffer a diastolic dysfunction which serves as a marker of a diabetic cardiomyopathy. Therefore, echocardiography with measurements of systolic and diastolic functional parameters appears to be a sensible method for evaluating the course of diabetic cardiomyopathy.

Adult↗