Biomedical subjects

J Piessens

Publications and source records attributed to J Piessens.

At least 37 records · Page 2Linked to original sources

PubMed1994

Angiotensin-converting enzyme inhibition with fosinopril sodium in the prevention of restenosis after coronary angioplasty.

BACKGROUND: Several angiotensin-converting enzyme inhibitors have antiproliferative effects in a rat model after carotid artery balloon injury. METHODS AND RESULTS: We conducted a randomized, double-blind, placebo-controlled trial to assess the effect of fosinopril, a novel angiotensin-converting enzyme inhibitor, in restenosis prevention after percutaneous transluminal coronary angioplasty (PTCA). Patients received fosinopril or matched placebo 10 mg at least 18 hours before PTCA, 20 mg at least 4 hours before PTCA, and 40 mg daily for 6 months. In addition, all patients received aspirin. Coronary angiograms before PTCA and immediately after PTCA as well as at 6-month follow-up were quantitatively analyzed. A total of 509 patients were recruited. The final per-protocol population consisted of 153 fosinopril-treated and 151 placebo-treated patients. Restenosis rates according to the National Heart, Lung, and Blood Institute criterion 4 (loss of > or = 50% of the initial gain [primary end point]) were 45.7% and 40.7% in the fosinopril and control groups, respectively (not significant). The respective mean differences in minimal coronary luminal diameter between post-PTCA and follow-up angiograms were -0.59 +/- 0.71 mm and -0.51 +/- 0.67 mm (not significant). Clinical events during the 6-month follow-up period, analyzed on an on-treatment basis, were ranked according to the most serious event. The respective numbers in the fosinopril and the control groups were for death, 0 and 0; myocardial infarction, 0 and 0; coronary artery bypass graft surgery, 1 and 3; repeat PTCA, 35 and 35; recurrent signs of ischemia necessitating early repeat coronary angiography and managed medically, 6 and 7; and none of the above, 111 and 106. All these differences were significant. CONCLUSIONS: Administration of fosinopril in a dose of 40 mg daily during 6 months after PTCA does not prevent restenosis and has no effect on overall clinical outcome.

Angioplasty, Balloon, Coronary↗

PubMed1994

Role of intravascular ultrasound in coronary artery disease: a new gold standard? An overview.

Although selective contrast coronary arteriography has been the gold standard approach for coronary imaging since more than 30 years, new coronary imaging techniques are currently under development. Intravascular ultrasound (IVUS) is perhaps the most promising of these additional techniques. IVUS makes use of miniaturised crystals incorporated at catheter tips and provides real time, cross-sectional and longitudinal, high resolution images of the arterial wall with three-dimensional reconstruction capabilities (Pandian, 1989; Coy et al., 1991; Liebsen & Klein, 1992). Different devices have been constructed. Actually two types are being used: mechanical (hand-rotated or motor-driven) systems and phased array systems using high-frequency (20-30 MHz) transducers (Bom et al., 1989). Coronary ultrasound imaging performed during catheterization is feasible and safe as demonstrated in several studies examining normal and pathologic coronary arteries (De Scheerder et al., in press).

Coronary Disease↗

PubMed1993

Angiographic predictors of recurrence of restenosis after Wiktor stent implantation in native coronary arteries.

Intracoronary stenting has been proposed as an adjunct to balloon angioplasty to improve the immediate and long-term results. However, late luminal narrowing has been reported following the implantation of a variety of stents. One of the studies conducted with the Wiktor stent is a prospective registry designed to evaluate the feasibility, safety and efficacy of elective stent implantation in patients with documented restenosis of a native coronary artery. To identify angiographic variables predicting recurrence of restenosis, the angiograms of the first 91 patients with successful stent implantation and without clinical evidence of (sub)acute thrombotic stent occlusion were analyzed with the Computer Assisted Angiographic Analysis System using automated edge detection. The incidence of restenosis was 44% by patient and 45% by stent according to the 0.72 mm criterion, and 30% by patient and 29% by stent according to the 50% diameter stenosis criterion. The risk for restenosis for several angiographic variables was determined using an univariate analysis and is expressed as odds ratio with corresponding confidence interval. The only statistically significant predictor of restenosis was the relative gain when it exceeded 0.48 using the 0.72 mm criterion (odds ratio 2.7, 95% confidence interval 1.1-6.4). Furthermore, the relation between the relative gain (increase in minimal luminal diameter normalized to vessel size) as angiographic index of vessel wall injury and relative loss (decrease in minimal luminal diameter normalized to vessel size) as index of neointimal thickening was analyzed using a linear regression analysis. When using the categorical approach to address restenosis, there is an increased risk for recurrent restenosis when the relative gain exceeds 0.48. The continuous approach underscores this concept by indicating a weak but positive relation between the relative gain and relative loss.

Aged↗

PubMed1993

Intra- and interobserver variability of a fast on-line quantitative coronary angiographic system.

To evaluate intra- and interobserver variability of an on-line quantitative coronary angiographic system, 2 independent observers measured 166 primary lesions excluding total occlusions before and after coronary angioplasty. Each observer repeated his measurement 3 times at 14 days interval. The average percent diameter stenosis results obtained by observer 1 and 2 were almost identical, before (62.2% +/- 12.0% and 62.6% +/- 11.4%, NS) and after (27.1% +/- 12.0% and 26.9% +/- 11.3%, NS) angioplasty. Variability was expressed as 95% limits of agreement (mean difference +/- 2 x SD). The intra-observer variability of observer 1 ranged from -6.6% to 6.6% before angioplasty and from -9.6% to 9.6% after angioplasty. The corresponding limits of observer 2 were -8.0% to 7.5% and -8.3% to 8.5%, respectively. The interobserver variability ranged from -10.4% to 9.6% before versus -12.5% to 13.1% after angioplasty. This variability was not influenced by vessel size. The widening of the limits observed after angioplasty was largely due to an increased variability in the measurements of the absolute minimal luminal diameter but not of the reference segment. We conclude that the intra- and interobserver variability of measurements obtained with an on-line quantitative angiographic system used for guiding coronary interventions is acceptable and without systematic bias in any direction for a wide range of primary coronary stenoses. However, the variability increases when images are acquired immediately after angioplasty.

Angioplasty, Balloon, Coronary↗

PubMed1993

Echocardiographic detection of acute myocardial ischemia during percutaneous transluminal coronary angioplasty.

The usefulness of echocardiography and Doppler for the detection of acute myocardial ischemia was evaluated during right coronary artery occlusion in 20 patients. The echocardiographic findings were compared with the occurrence of chest pain, and to electrocardiographic and hemodynamic changes obtained during percutaneous transluminal coronary angioplasty. Our results confirm that, even in the case of small segmental myocardial ischemia, two-dimensional echocardiography is superior to all other measured parameters. In contrast, Doppler examination of transmitral flow is not sensitive enough for the detection of such small segmental myocardial ischemia induced by right coronary artery occlusion.

Adult↗

PubMed1993

Clinical applications of echocardiography in patients with acute myocardial infarction.

The ability of echocardiography to visualize ventricular wall motion abnormalities induced by ischaemia and infarction makes it an ideal tool in the assessment of patients with acute myocardial infarction. Echocardiographic derived measurements of infarction severity, such as the wall motion score index, correlate well with both early and late complications. Echocardiography is of considerable value in the detection of mechanical complications of myocardial infarction such as aneurysm and thrombus formation, infarction expansion, ventricular septal rupture and mitral regurgitation; Doppler echocardiography is of particular worth in the detection of the latter two complications. Serial echocardiographic imaging before and after various coronary reperfusion strategies allows useful assessment of the success of these strategies. Following a myocardial infarction, a predischarge resting or exercise 2-dimensional echocardiographic study provides valuable information regarding the likelihood of adverse cardiac events during long term follow-up.

Echocardiography↗

PubMed1993

The use of intracoronary ultrasound for quantitative assessment of coronary artery lumen diameter and for on-line evaluation of angioplasty results.

UNLABELLED: The value of intracoronary ultrasound for quantitative assessment of minimal coronary arterial diameter and for on-line evaluation of balloon angioplasty result was studied in 42 patients undergoing single vessel coronary angioplasty. Measurement of minimal luminal diameter of 75 matched coronary arterial segments showed a significant correlation between both the ultrasound and angiographic method (r: 0.759; p < 0.001). Furthermore using intravascular ultrasound it was possible to classify the obtained coronary balloon angioplasty results. A preliminary correlation between ultrasound classification and the in-hospital acute rethrombosis as well as late restenosis was attempted in individual patients. CONCLUSIONS: 1) Clinical use of coronary ultrasound is feasible and safe in selected cases. 2) A significant correlation between intracoronary ultrasound and quantitative coronary angiography is demonstrated. 3) Using intracoronary ultrasound seems promising for evaluation of the postangioplasty result, and may finally lead to improved selection of the interventional strategy.

Angioplasty, Balloon, Coronary↗

PubMed1992

Immediate and follow-up results of the conservative coronary angioplasty strategy for unstable angina pectoris.

To assess the results of a conservative coronary angioplasty strategy in unstable angina pectoris, the records of 1,421 consecutive patients without previous myocardial infarction undergoing a first percutaneous transluminal coronary angioplasty (PTCA) between 1986 and 1990 were reviewed. Of these patients, 631 had unstable and 790 had stable angina pectoris. Only after an intense effort to medically control symptoms, the unstable patients underwent PTCA at an average of 15.4 days (range 1 to 76) after hospital admission. Primary clinical success was achieved in 91.7% of patients with unstable and in 94.4% of those with stable angina pectoris (p = not significant). In-hospital mortality rates were 0.3 and 0.1%, respectively (p = not significant). Nonfatal in-hospital event rates for acute myocardial infarction, cerebrovascular accident and coronary bypass surgery were only slightly higher in patients with unstable angina pectoris; however, the difference from the stable group was significant when all events were combined (9 vs 5.9%; p less than 0.04). During 6-month follow-up, no significant difference in adverse events was found between the groups. The respective rates for the unstable and stable groups were 0.4 and 0.2% for death, 5.5 and 5.1% for major nonfatal events, and 17.7 and 20.1% for repeat PTCA. These results suggest that use of a conservative PTCA strategy in the treatment of patients with unstable angina pectoris results in favorable and similar immediate and 6-month outcomes compared with those in patients with stable angina pectoris.

Angina Pectoris↗

PubMed1992

Wiktor stent implantation in patients with restenosis following balloon angioplasty of a native coronary artery.

Intracoronary stenting has been introduced as an adjunct to balloon angioplasty aimed at overcoming its limitations, namely acute vessel closure and late restenosis. This study reports the first experience with the Wiktor stent implanted in the first 50 consecutive patients. All patients had restenosis of a native coronary artery lesion after prior balloon angioplasty. The target coronary artery was the left anterior descending artery in 26 patients, the circumflex artery in 7 patients and the right coronary artery in 17 patients. The implantation success rate was 98% (49 of 50 patients). There were no procedural deaths. Acute or subacute thrombotic stent occlusion occurred in 5 patients (10%). All 5 patients sustained a nonfatal acute myocardial infarction. Four of these patients underwent recanalization by means of balloon angioplasty; the remaining patient was referred for bypass surgery. A major bleeding complication occurred in 11 patients (22%): groin bleeding necessitating blood transfusion in 6, gastrointestinal bleeding in 3 and hematuria in 2. Repeat angiography was performed at a mean of 5.6 +/- 1.1 months in all but 1 patient undergoing implantation. Restenosis, defined by a reduction of greater than or equal to 0.72 mm in the minimal luminal diameter or a change in diameter stenosis from less than to greater than or equal to 50%, occurred in 20 (45%) and 13 (29%) patients, respectively. In this first experience, the easiness and high technical success rate of Wiktor stent implantation are overshadowed by a high incidence of subacute stent occlusion and bleeding complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗

PubMed1992

The conservative coronary angioplasty strategy after thrombolysis for acute myocardial infarction: immediate and short-term results.

The in-hospital and short-term follow-up results of a conservative coronary angioplasty approach in 354 consecutive patients treated after thrombolysis for acute myocardial infarction were compared with results obtained in 408 control noninfarcted patients treated for the classical indication of myocardial ischemia. Only 20% of the study patients underwent angioplasty during the initial hospitalization period and the clinical success rate was 93% versus 95% in the control group (p = NS). No significant differences in the total number of in-hospital untoward events were observed (10.2% and 7.6%, respectively). During a 7.4 +/- 1.5 month follow-up period, the total number of adverse events was only 16.9% in the study patients but it was 27.8% in the control group (p < 0.001). There were no significant differences in death, myocardial infarction, or coronary surgery as individual events, but repeat angioplasty was less frequent in the study group (14.0% versus 21.5%, p < 0.01). Thus in-hospital results in patients undergoing angioplasty on a deferred basis after thrombolysis for myocardial infarction were largely comparable with those results obtained in noninfarcted patients. Moreover, short-term clinical follow-up events were reduced when compared with the control group, an observation apparently largely related to the subgroup without clinical evidence of residual ischemia.

Aged↗

PubMed1992

Transluminal coronary balloon angioplasty: a useful therapeutic modality in octogenarian patients with severe angina.

In this study, the immediate and short-term outcome of 9 consecutive patients aged 80 years or older undergoing percutaneous transluminal coronary angioplasty (PTCA) are reported. Of these 9 patients, 8, despite optimal medical therapy, had unstable Class IV anginal symptoms and 6 had multivessel coronary artery disease. Primary success at PTCA (successful dilation of all attempted lesions without any complications) was achieved in 8 of the 9 (89%) patients. The one patient with unsuccessful PTCA had subsequent successful elective coronary bypass graft surgery. The 8 patients with primary success at PTCA have been followed up for a mean of 27 +/- 15 (range: 6 to 45) months. During follow-up, no patient died, required a further revascularization procedure or had a myocardial infarction. Indeed, 7 of these 8 patients have, following PTCA, remained entirely asymptomatic with no decrease in their activity level. Angina has recurred in 1 patient but it is mild and does not restrict his activities. Based on our encouraging experience we suggest that PTCA should be considered favourably in the treatment of selected octogenarian patients with severe angina poorly controlled by medical therapy.

Aged↗

PubMed1992

Isolated single coronary artery: a review of 50,000 consecutive coronary angiographies.

Single coronary artery is a rare congenital anomaly of the coronary arteries where only one coronary artery arises from the aortic trunk by a single coronary ostium, supplying the entire heart. A database consisting of the angiographic reports of 50,000 consecutive coronary angiographies performed in adult patients in the University Hospital of Leuven between March 1973 and August 1991 was searched for the diagnosis of single coronary artery. All films concerned were reviewed and classified according to their anatomical type. Thirty-three cases of single coronary artery were retrieved, yielding an incidence of 0.066%. Patient characteristics and clinical data are described, with a discussion on the pathological importance of this finding.

Adult↗

PubMed1992

Specific coronary hemodynamic effects of nisoldipine and other vasoactive drugs.

The specific coronary hemodynamic effects of different vasoactive drugs were studied using a randomized, double-blind protocol in the "normal" contralateral artery after performing single-vessel coronary angioplasty. The intracoronary administration of 50 micrograms of nisoldipine resulted in an increase in epicardial diameter (+19%; p = 0.0001) and in coronary blood flow (+47%; p = 0.003), but the flow reserve decreased (-20%; p = 0.001). In placebo-treated patients, all parameters proved to be very stable and no significant changes were found. In a second study, 500 micrograms of diltiazem i.c. was administered to 20 patients, who were first randomized to pretreatment with either placebo (n = 10) or isosorbide dinitrate (0.5 micrograms/kg/min infusion; n = 10). There were increases in epicardial diameter (+10%; p = 0.0001) and coronary flow (+30%; p = 0.0001) in all patients. These changes were comparable in patients pretreated with placebo or nitrates but the reduction in coronary flow reserve was only significant in patients pretreated with placebo (+19%; p = 0.0008). In a third study, the hemodynamic effects of the intracoronary application of SIN-1 (500 micrograms), the active metabolite of molsidomine, were studied. There was a consistent increase in epicardial diameter (+26%; p < 0.0001) but the response at the microvascular level was heterogeneous and characterized by a trend to increased blood flow (+25%; p = 0.11) and decreased coronary vascular resistance (-18%; p = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗

PubMed1991

Ridogrel in the setting of percutaneous transluminal coronary angioplasty.

The safety of the combination of heparin and ridogrel therapy and its antiplatelet efficacy was examined in the setting of percutaneous transluminal coronary angioplasty (PTCA). In 32 patients without known aspirin intake for 10 days before PTCA, therapy with ridogrel (300-mg intravenous bolus) was begun just before PTCA and continued orally at a dose of 300 mg twice daily until discharge. Heparin was administered as a 10,000 IU bolus dose before PTCA and followed by an intravenous infusion at a rate of 1,000 IU/hour for 24 hours. Bleeding problems at the arterial entry site occurred in 13 patients, which required a blood transfusion in only 2 patients. One patient underwent emergency bypass surgery without specific problems of hemostasis. Ridogrel virtually eliminated thromboxane B2 from the serum (29,990 +/- 6,555 pg/0.1 ml before vs 63 +/- 7 pg/0.1 ml at 2 hours after ridogrel), with a concomitant increase in serum 6-keto-prostaglandin F1 alpha (511 +/- 34 pg/0.1 ml before vs 1,190 +/- 146 pg/0.1 ml at 24 hours after ridogrel). There were no acute reocclusions in the ridogrel-treated patients, whereas acute reocclusions occurred in 5.6% of the patients taking the standard aspirin + heparin regimen during the same period. Furthermore, at 6-month clinical follow-up patients treated with ridogrel compared favorably with those receiving standard treatment.

6-Ketoprostaglandin F1 alpha↗

PubMed1991

Immediate and short-term results of a 1988-1989 coronary angioplasty registry.

To determine the relevance of recent refinements in angioplasty technology to our particular practice, the records of 507 consecutive patients undergoing a first percutaneous transluminal coronary angioplasty (PTCA) at our center between October 1988 and May 1989 were reviewed. At the time of PTCA, 41% of these patients had class IV angina and 44% were identified as having multivessel disease. Dilatation was attempted in 734 lesions (mean 1.5 per patient), of which 95 (13%) were chronic total occlusions. Overall, 69% of the 734 lesions were judged anatomically complex, and, in dilating these lesions, a rail-type device was used almost exclusively. Successful dilatation was achieved in 659 of the 734 (90%) attempted lesions. There were low incidences of the major complications of death (0.4%), myocardial infarction (1.8%) and emergency bypass surgery (1.8%). Acute rethrombosis occurred in 54 patients (11%). In these patients, initial strategy of repeat dilatation was successful in 38 of 47 patients (81%). Overall, primary clinical success at PTCA was achieved in 480 patients (95%). At a mean follow-up of 7.5 +/- 1.5 months in 497 of the study patients, the event-free rate (freedom from cardiac death, myocardial infarction, repeat PTCA or coronary bypass surgery or recurrence of severe [class III to IV] angina) was 71%. In conclusion, despite the often complex coronary disease in patients currently presenting to our center, a high initial success rate and acceptable short-term outcome of PTCA was achieved.

Aged↗

PubMed1991

Lack of evidence for small vessel disease in a patient with "slow dye progression" in the coronary arteries.

A patient with chest pain of recent onset, suggestive for angina pectoris, was referred for diagnostic coronary angiography, which showed the typical phenomenon of "slow dye progression" in the absence of any significant coronary artery stenosis. While intracoronary Doppler measurements confirmed the extremely slow blood flow velocity, the coronary flow reserve and the calculated coronary blood flow proved to be within normal range. The present findings suggest that, in contrast with a previous hypothesis, the phenomenon of slow dye progression may not always be due to a microvascular cause. Epicardial artery disease, as suggested by the marked coronary artery ectasia, may be linked to the slow dye progression and predispose to coronary artery thrombosis.

Blood Flow Velocity↗

PubMed1991

Morphologic change in coronary artery stenosis with the Medtronic Wiktor stent: initial results from the core laboratory for quantitative angiography.

The purpose of this study was to assess the early changes in stenosis geometry after implantation of the Medtronic Wiktor stent in human coronary arteries. Morphologic changes were evaluated by quantitative coronary angiography using automated edge detection. The hemodynamic significance of the morphologic changes were assessed by the calculation of the theoretical pressure drop across the dilated and stented stenosis derived from the Poiseuile and turbulent resistances assuming a coronary blood flow of either 0.5, 1, or 3 ml/sec. Fifty patients were studied before and immediately after stent implantation. The stented coronary artery was the left anterior descending artery in 26 patients, the circumflex artery in eight patients, and the right coronary artery in 16 patients. Stent implantation resulted in an additional increase in the minimal luminal cross-sectional area and minimal luminal diameter of the dilated vessel without changing the curvature of the stenosis. Furthermore, there was a significant reduction of the "plaque area." This was associated with a normalization of the calculated resistances to flow and pressure drop across the stenosis. To a minimal extent, recoil (0.1 +/- 0.36 mm) was observed after stent implantation.

Adult↗

PubMed1991

Prospective study on prevalence of esophageal chest pain in patients referred on an elective basis to a cardiac unit for suspected myocardial ischemia.

The prevalence of esophageal chest pain was studied prospectively in patients referred on an elective basis to a cardiac unit for suspected myocardial ischemia. A group of 248 consecutive patients without previously documented heart disease was admitted for elective diagnostic coronary angiography. The clinical history classified 185 patients as having anginal pain and the coronary angiogram was normal in 48 of them. In 37 of these 48 patients full esophageal testing was performed including 24-hr intraesophageal pH and pressure recordings with indication of chest pain episodes as well as a number of esophageal provocation tests, ie, acid perfusion, edrophonium stimulation, balloon distension, and ergonovine stimulation, all performed under continuous esophageal manometric and electrocardiographic monitoring. In 19 of these 37 patients, the familiar chest pain could be reproduced by esophageal provocative testing without ischemic ST-T segment alterations; six of these 19 patients had also a positive 24-hr pH and pressure recording. These data strongly suggest an esophageal origin of chest pain in half the patients with typical angina and a normal coronary angiogram.

Angina Pectoris↗