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C Vrints

Publications and source records attributed to C Vrints.

36 records · Page 2Linked to original sources
PubMed1996

Cyclic flow variations after angioplasty: a rare phenomenon predictive of immediate complications. DEBATE Investigator's Group.

Experimental studies and studies in human beings have indicated that cyclic flow variation (CFV) is a reliable marker of the formation of platelet aggregates and thus may be predictive of immediate complications after coronary angioplasty. In this study, the incidence and clinical relevance of CFV in a large patient population after elective percutaneous transluminal coronary angioplasty (PTCA) was assessed. One hundred two patients with one-vessel disease and no previous Q-wave myocardial infarction underwent angiographically successful PTCA of a single lesion of a major coronary artery. A Doppler guide wire inserted distal to the stenosis was used to monitor flow velocity continuously after PTCA for 15 minutes. In 94 (92%) of 102 patients, a stable and reliable Doppler signal could be recorded for 15 minutes after the procedure. CFV, defined as gradual decline in flow over several minutes followed by a sudden restoration to higher values, was observed in 4 patients. In 3 of these 4 patients, the occurrence of CFV was predictive of immediate complications (2 intracoronary thrombosis and 1 acute closure), whereas none of the patients without CFV (n = 90) showed acute closure during hospital stay. In conclusion, CFVs in patients after angiographically successful elective PTCA are rare (4.3%) but highly sensitive for the prediction of abrupt occlusion.

Aged↗
PubMed1994

Nosocomial septicaemias in a cardiologic ward. A case-control study.

Nosocomial septicaemias were studied in a cardiologic ward at the University Hospital of Antwerp, Belgium. The incidence of nosocomial infections was found to be 2.7 per 1,000 admissions per year. A case-control study suggested that in contrast with coronarography and pacemaker implantation, percutaneous transluminal coronary angioplasty may be a risk factor for nosocomial septicaemia (OR 4.5, 95% confidence interval 0.7-33.4).

Aged↗
PubMed1994

High atrial pacing impedance: efficient or wasteful? A comparison of an active and a passive fixation lead.

We compared the stimulation characteristics of two atrial fixation leads: the CPI model 4269 (n = 45) and Cordis-Telectronics model 327-752 (n = 42). The CPI lead uses an active fixation method, whereas the Cordis-Telectronics lead is fixated passively. Impedance and threshold were measured at implant and during 12 months of follow-up. P wave sensing was good with both types of leads. Follow-up of these 87 leads showed that both the impedance and threshold increased with the active leads, but not with the passive fixation leads. In the active fixation group, regardless of the high atrial pacing impedance, 93% could still be programmed to 2.5 V-0.6 msec (with a 2:1 threshold safety margin). It is concluded that the high chronic pacing impedance of the active fixation leads will be beneficial on current drain if no major increase in pacing threshold occurs simultaneously.

Cardiac Pacing, Artificial↗
PubMed1992

External vibration interference of activity based rate responsive pacemakers.

The change of the pacing rate in response to external vibration interference was assessed in four rate responsive pacemakers with a piezoelectric crystal (Medtronic Activitrax 8403, Siemens Sensolog 3, Biotronik Ergos 01, and Medtronic Legend 8417) and one with an accelerometer (CPI Excel VR 1119). They were tested in the laboratory. External vibration was simulated in vitro by exposing the different pacemakers to a controlled sinusoidal vibration force generated by a Millar pressure vibration amplifier type MGM-30 (Millar Instruments, Inc., Houston, TX, USA). All pacemakers were programmed at standard settings. Two types of vibration forces were applied: (1) one with varying amplitude but with constant vibration frequency; and (2) one with varying frequency but with constant vibration amplitude. In this manner curves of pacing rate versus vibration forces versus vibration frequency were obtained. High vibration forces and low vibration frequencies were associated with the highest pacing rate response. In this experimental setting, the pacemaker based on the accelerometer principle apparently was the least sensitive to high frequency vibrations, which are known to be related to environmental interference. It also seemed more appropriately responsive in the lower frequency range, which is more appropriate for the detection of true physiological activity.

Acceleration↗
PubMed1992

Predictive value of the P wave at implantation for atrial fibrillation after VVI pacemaker implantation.

This study assesses the value of P wave measurements on the surface ECG at implantation, in the prediction of atrial fibrillation in VVI paced patients. From a consecutive series of 320 pacemaker implantations 172 VVI paced patients for symptomatic atrioventricular block (AVB) (n = 126; mean age 69 +/- 14) or sick sinus syndrome (SSS) (n = 56; mean age 68.6 +/- 12) and in sinus rhythm at implantation were used in this study. P wave duration in V1 is correlated with the incidence of atrial fibrillation during 5 years of follow-up. V1 at implantation was significantly longer (114.6 +/- 2.7 msec) in the patients who developed atrial fibrillation than in those who did not (91.9 +/- 2.7 msec) (P < 0.001). Although positive predictive accuracy increases progressively for higher V1 values for AVB and SSS, the negative predictive and diagnostic accuracy of V1 criteria were less in SSS. Application of the Bayes' theorem showed that in SSS the probability to develop atrial fibrillation is 33% for V1 < 110 msec and is for V1 < 90 msec still higher than that reported in DDD paced patients. In the AVB group the probability to develop atrial fibrillation is 8% for V1 < 110 msec and 6% for V1 < 100 msec. It seems, therefore, that atrial stimulation (AAI or DDD) is always indicated in SSS. In AVB with V1 < 100 msec, DDD pacing, if not needed for other indications, apparently does not offer much benefit in the prophylaxis of atrial fibrillation.

Aged↗
PubMed1992

[P wave changes and atrial fibrillation after implantation of VVI type pacemaker].

The P waves of patients with VVI pacemakers were compared with those of DDD pacemakers at implantation and then regularly for 5 years. A certain number of cardiac pathologies are known to cause P wave changes. The incidence of atrial fibrillation (AF) was much higher in VVI than in DDD patients. In the VVI group, the incidence was much greater in patients paced for sinus node disease than in patients paced for AVB. Analysis of sinus P wave characteristics in 320 patients with VVI pacemakers shows progressive abnormalities of atrial function with time. The expression of this atrial dysfunction is a statistically significant prolongation of the P wave in V1 and dII and of the terminal part of the P wave in V1. The factors responsible for this abnormality and which favours the occurrence of AF are quasi-permanent pacing, the presence of retrograde conduction and an abnormality of atrial activation at the time of implantation.

Aged↗
PubMed1990

Evolution of P wave characteristics after pacemaker implantation.

This study is an investigation of the long-term effects of VVI pacing on the atrium as derived from the evolution of P wave characteristics of 285 patients. The occurrence of left and right atrial disease is demonstrated as well as the evolution of left atrial hypertrophy in some cases. A comparison is made with DDD pacing and special attention is given to the progression to atrial fibrillation.

Aged↗
PubMed1989

Simultaneous bipolar pacing and sensing during EPs.

Bipolar pacing and sensing-recording on the same electrode is a problem during pacemaker implantation as well as during electrophysiological studies. A method is described that makes this possible. By using bipolar simultaneous sensing-pacing on the same electrode, the system can record local repolarization after a depolarization controlled by stimulation. The bipolar-paced evoked potential is useful as an indicator to drive a bipolar QT rate responsive pacemaker. Even more, during EPS it can be used to detect capture during tachycardia stimulation and to measure the exact refractory period.

Carbon↗
PubMed1988

Subocclusion of the left anterior descending artery following blunt chest trauma.

A 54-year-old man complained of severe angina shortly after a blunt chest trauma and coronary angiography showed an isolated subtotal occlusion of the mid-left anterior descending artery. Bypass grafting was uneventful. Posttraumatic angina or supposed myocardial contusion may be due to coronary injury for which a specific treatment can be given to limit the extent of myocardial necrosis.

Arteries↗
PubMed1986

Diagnostic value of R wave amplitude changes during exercise testing after myocardial infarction.

To determine the diagnostic value of R wave amplitude changes occurring during exercise testing after myocardial infarction, exercise ECG's and coronary angiograms were reviewed in 76 postinfarction patients and in 40 patients with normal coronary arteries. During exercise, an increase in R wave amplitude (mean: + 2.7 +/- 1.3 mm) was observed in the postinfarction patients, significantly different (P less than 0.001) from the decrease (mean: - 2.6 +/- 1.1 mm) observed in the group with normal coronary arteries. Although this change increased with the number of diseased coronary arteries, the difference between 1-vessel and multi- or 3-vessel disease was not significant. Extension of infarct size from one to more akinetic segments on the left ventricular angiogram was associated with a significant (P less than 0.001) increase of the R wave amplitude change during exercise (mean: + 1.6 +/- 1.1 vs 3.3 +/- 1.3 mm). It is concluded that the abnormal increase in R wave amplitude observed during exercise testing after myocardial infarction is more strongly related to infarct size then to the number of diseased coronary arteries. Furthermore exercise induced R wave amplitude changes have no diagnostic value in the prediction of multi- or 3-vessel disease in postinfarction patients.

Angiocardiography↗
PubMed1984

Cardiac involvement in juvenile ceroid lipofuscinosis of the Spielmeyer-Vogt-Sjögren type: prospective noninvasive findings in two siblings.

The results of prospective noninvasive cardiologic investigations, including echocardiography and Holter monitoring are described in 2 siblings with juvenile ceroid lipofuscinosis of the Spielmeyer-Vogt-Sjögren type. In the elder patient, echocardiography revealed ventricular hypertrophy with slowed ventricular relaxation. Holter monitoring showed not only bradycardia but also slow and fast ectopic atrial rhythms, sinus arrests and complex ventricular ectopic activity including ventricular tachycardia. In the younger patient the findings were less severe. These functional disturbances due to cardiac involvement, never reported before in this disease, are discussed.

Adult↗
PubMed1984

Indications for coronary arteriography after myocardial infarction.

The prognosis of patients after an acute myocardial infarction depends on the extent of the myocardial damage, its resulting left ventricular dysfunction and on the number and degree of narrowing of diseased coronary arteries. Patients with a severe multivessel disease constitute a high-risk group with an important morbidity and mortality during the first few months after hospitalization for a myocardial infarction. They could benefit from early revascularization therapy, whether by coronary artery bypass surgery, whether by percutaneous transluminal coronary angioplasty. Although early coronary revascularization is still controversial, management of patients after a myocardial infarction certainly will improve from a more accurate risk profiling by a careful diagnostic evaluation--including coronary arteriography in some subsets of patients--during the in-hospital period.

Coronary Angiography↗
PubMed1983

Cardiac manifestations of Becker-type muscular dystrophy.

The electro-, phonomechano- and echocardiographic manifestations observed in a family with documented X-linked Becker-type muscular dystrophy (BMD) are described. Important myocardial dystrophic lesions may occur in young patients with BMD. They are associated with typical electrocardiological findings which were described as a distinctive pattern in Duchenne-type muscular dystrophy. Myocardial involvement is seldom observed in heterozygotes for BMD.

Adult↗
PubMed1982

Influence of intravenous hyperalimentation on cardiac dimensions and heart function.

Eleven severe malnourished patients, mean age 34 yrs and mean weight 66 per cent of ideal body weight, were studied to evaluate the effect of intravenous hyperalimentation on the function and size of the heart. Left ventricular size and systolic function were measured before and after a mean weight gain of 19 per cent with electro, vector, echo and phonomechanographic methods. During hyperalimentation a statistically significant increase in left ventricular mass (p<0.01) was observed. Correction for body weight showed a parallel increase between the parameters and weight gain. Echocardiographic and phonomechanographic indexes of left ventricular systolic function remained unchanged. A decrease of the amplitude of the maximal spatial QRS vector was shown by vectocardiography. These results indicate that during intravenous hyperalimentation of the severe malnourished a proportional increase in cardiac size and mass occurs with preservation of the left ventricular systolic function.

Journal Article↗
PubMed1981

Myopotential inhibition of unipolar ventricular inhibited pacemakers: prevention by an insulating sheath.

To determine the occurrence of inhibition of pacing by sensing of myopotentials, forty-five patients with predominant pacemaker driven heart rhythm were studied. In eleven patients with a bipolar lead system myopotential inhibition was never observed. In the remaining group (34 patients) with unipolar pacemakers myopotential inhibition was demonstrated in fifteen patients. Three of them were symptomatic, two severely. In forty new implants a silicone-rubber insulating sheath was placed against the muscular side of the pacemaker. In none of these patients myopotential inhibition could be demonstrated. The authors conclude that myopotential inhibition occurs frequently in unipolar ventricular inhibited pacemakers, and can be prevented by insulating the muscular side of the anodal surface.

Electric Conductivity↗