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Biomedical subjects

P Zarco

Publications and source records attributed to P Zarco.

At least 55 records · Page 3Linked to original sources
PubMed1992

Midterm outcome of patients with asymptomatic restenosis after coronary balloon angioplasty.

Although many patients with restenosis after balloon coronary angioplasty have recurrence of angina, others remain asymptomatic. To assess the clinical implications of asymptomatic coronary restenosis, we analyzed clinical and angiographic characteristics of 277 consecutive patients with restenosis, 133 (48%) of whom were asymptomatic (group I) and 144 (52%) symptomatic (group II). Restenosis was documented 6 to 9 months after the index procedure, or earlier if angina recurred, and was defined as a greater than 50% lumen narrowing (visual estimation). Group I (asymptomatic group) included fewer female (9% vs. 18%, p less than 0.05) and hypertensive patients (38% vs. 56%, p less than 0.005) and more patients with a previous myocardial infarction (48% vs. 28%, p less than 0.05) and single-vessel disease (67% vs. 55%, p less than 0.05). Before angioplasty, symptoms had lasted for a shorter period (10 +/- 25 vs. 23 +/- 42 months, p less than 0.001), ischemia after a recent infarction was a more frequent indication (21% vs. 10%, p less than 0.05) and total revascularization more frequently obtained (74% vs. 63%, p less than 0.05) in group I than in group II patients. Only a normal blood pressure, previous myocardial infarction, single-vessel disease and a shorter duration of symptoms were independent correlates of asymptomatic restenosis. No differences were found in stenosis severity before angioplasty (90% in both groups) or after angioplasty (22% +/- 12% vs. 24% +/- 16%).(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗
PubMed1992

Involvement of platelet-activating factor and tumour necrosis factor in the pathogenesis of joint inflammation in rabbits.

We have studied the participation of platelet-activating factor (PAF) in antigen-induced arthritis in rabbits, as well as the possible co-operation between PAF and tumour necrosis factor (TNF) in their ability to induce joint inflammation when injected into the knees of healthy rabbits. The administration of two structurally different PAF receptor antagonists, BN52021 and Alprazolam, from 4 h before the intra-articular injection of ovalbumin in preimmunized rabbits, induced an important reduction in the synovial fluid volume, in the amount of cells infiltrating the articular cavity and the synovial membrane, as well as in the prostaglandin E2 (PGE2) concentration. Furthermore, proteoglycans of the articular cartilage, which were found diminished in animals with non-treated arthritis, were well preserved in rabbits treated with PAF antagonists. All the synovial fluids from joints with arthritis had detectable amounts of PAF. The injection of either TNF or PAF into the joints of normal rabbits induced a mild inflammation. When TNF was administered 1 h before PAF, a synergistic response was noted in the synovial fluid volume, in the accumulation of leucocytes, and in the amount of PGE2. The administration of BN50726, a hetrazepine with a potent PAF-receptor antagonist effect, induced a diminution in those parameters. Our results suggest that PAF may be an early and important mediator of joint damage, and that TNF can amplify the inflammatory response induced by PAF. PAF receptor antagonists could play some role in the treatment of inflammatory joint diseases.

Animals↗
PubMed1992

[Conventional and color Doppler echocardiography in mitral balloon valvotomy].

With the aim of assessing the value of conventional echocardiography and Doppler and colour Doppler during and in the follow-up of percutaneous mitral valvotomy we have studied prospectively 100 consecutive patients with 1 (90%), 6 (69%) and 12 (53%) months follow-up. Age was 50 years and 80% were women. The single balloon technique was used in 68%, mitral valve area increased from 0.9 +/- 0.2 to 1.8 +/- 0.3 cm2 and decrease in pulmonary artery pressure was 10 +/- 0.05 mmHg. We found that: 1) percutaneous mitral valvotomy produced and acute and transient decrease in left ventricular ejection fraction (pre 69 +/- 9%, post 61 +/- 10% p less than 0.001; 1 month 70 +/- 10; 2) a severe mitral regurgitation appeared in 4% of patients and 17% of patients had a moderate degree of regurgitation after valvotomy; 3) after valvular dilation an increase in the width of the aliasing greater than 29% predicted a successful procedure (final area greater than 1.5 cm2) with a sensibility 80% and specificity 94%, and 4) colour Doppler detected an atrial septal defect immediately after valvular dilation in 77% of patients, and permitted non invasive follow-up of the left to right shunt. At one year a left to right shunt at the atrial level persisted roughly in 1/3 of patients. We conclude that colour Doppler Echocardiography during percutaneous mitral valvotomy is useful for a rapid assessment of the increase in valve area, the detection and quantification of mitral regurgitation induced by valvular dilation and the follow-up in these patients.

Aortic Valve Insufficiency↗
PubMed1992

[The usefulness of intravascular echography during the percutaneous dilatation of aortic coarctation].

An intravascular ultrasound study was performed in a patient, to assess the anatomy of aortic coarctation and the results obtained after percutaneous dilation with a balloon catheter. Intravascular ultrasound imaging provides important additional information, not obtainable with other diagnostic procedures, regarding aortic wall structure and thickness. After balloon dilation, aortic disruption was clearly observed, accounting, together with the stretching of the outer layers of the aortic wall, for the increase in aortic luminal area. Intravascular ultrasound permitted also the accurate assessment of the improvement obtained. Intravascular imaging was clearly superior not only to conventional angiography, but also to transesophageal echocardiography in detecting the mechanism of dilation. We conclude that ultravascular ultrasound, with the additional information that it provides, may help in the selection of patients for percutaneous dilation of the coarctation as well as contributing to the identification of the mechanism of dilation.

Aorta, Thoracic↗
PubMed1992

[The evaluation of the results after coronary angioplasty by intracoronary Doppler and quantitative angiography. The correlation of both methods].

To study the importance of measuring coronary flow reserve immediately after coronary angioplasty we have analysed the results obtained after 28 angioplasties performed in 21 patients. Coronary flow reserve was measured with a 3F intracoronary catheter selectively placed in the dilated artery. Corresponding coronary angiography was analysed with an automatic edge detection program (ARTREK) and visual estimation. Coronary flow reserve increased in 26/27 cases after angioplasty from 2.4 +/- 1.3 to 4.1 +/- 2.7 (p less than 0.001). A correlation was found between minimal luminal area and minimal luminal diameter after coronary angioplasty, and coronary flow reserve (r = 0.46; p less than 0.05 and r = 0.47; p less than 0.05, respectively). The finding of a normal coronary flow reserve (greater than or equal to 3.5), had a 100% specificity but only 56% sensitivity to detect angiographic success (residual stenosis less than 50%). However 47% of patients with angiographic success did not reach normal values of coronary flow reserve. Visual estimation of the stenosis had a good correlation with automatic evaluation but significant scattering was observed at visual levels less than or equal to 25%. Visual assessment underestimated residual stenosis in all but one of the procedures. We conclude that coronary flow reserve is a potentially useful index for assessing the results after angioplasty that may complement coronary angiography. Nonetheless substantial differences between both methods exist in a significant number of cases. The relative merits of both methods, as well as the particular circumstances in which coronary flow reserve should be used, require further studies.

Angioplasty, Balloon, Coronary↗
PubMed1992

[The correlation between measurements performed by intravascular echography and quantitative digital angiography in large- and small-caliber arteries].

Intravascular ultrasound is a new promising technique that appears as a very useful complement to standard angiography in the study of atherosclerosis. Specifically, intravascular ultrasound provides by itself, information of great value concerning vessel wall characteristics. Nevertheless, before taking any decision with the results provided by this new technique, we must validate this information with that provided by other more conventional techniques like standard angiography. Accordingly, we have analyzed in 25 patients, 50 images of the abdominal aorta and 77 images of the coronary arteries taken from arterial segments free of atherosclerotic involvement. With the use of a calibrated small grid located over the patient's thorax, we have analyzed "in the same points" the images obtained with intravascular ultrasound and those provided by contrast angiography using a quantitative angiographic analysis. In the abdominal aorta the vessel diameter measured by intravascular ultrasound and angiography was 17.8 +/- 0.39 mm vs 18.6 +/- 0.42 mm (NS), whereas in the coronary arteries it was 2.76 +/- 0.39 mm vs 2.98 +/- 0.37 mm (NS), respectively. The correlation between both techniques was good for both types of arteries (r = 0.93 in the abdominal aorta and r = 0.87 in the coronary arteries). We conclude, that in our experience and with the methodology used, there is a good correlation between the measurements of the vessel diameters obtained by both intravascular ultrasound and digital angiography in arteries of different sizes, being the correlation even better in large arteries.

Adult↗
PubMed1992

[Transluminal percutaneous coronary angioplasty of the left coronary artery].

This paper describes our preliminary experience with left main coronary angioplasty in 8 patients (9 procedures). In 6 patients the left main coronary artery was "protected" either by previous by-pass surgery (4 patients) or by collateral vessels from the right coronary artery (2 patients). Three patients had a total occlusion of the left main coronary artery and 2 of them had a recent or acute myocardial infarction and the coronary angiogram suggested a thrombotic occlusion of the infarct-related artery. Three patients were not considered surgical candidates and an additional patient, who was in cardiogenic shock, required an emergency coronary angioplasty as "rescue" procedure. A successful dilatation was achieved in 6 patients (including a patient with successful deployment of a Palmaz-Schatz stent) but, unfortunately, one them eventually died 7 days later from a femoral sepsis related to the procedure. However in the 2 remaining patients--with a total occlusion of the left main coronary artery in relation with a myocardial infarction--the dilatation procedures were unsuccessful. One patient underwent a successful repeat coronary angioplasty for restenosis of left main coronary artery. Our preliminary experience confirms previous reports suggesting the value of coronary angioplasty in patients with left main coronary artery disease providing a careful selection of possible candidates is performed prior to the procedure.

Adult↗
PubMed1991

[The results of percutaneous transluminal coronary angioplasty in lesions with thrombi].

Previous studies have suggested that the results of coronary angioplasty are poorer when the attempted lesion has a thrombus associated. With the aim of assessing the results of coronary angioplasty in lesions with thrombus, 1,192 consecutive coronary lesions attempted were prospectively analyzed. Of these, 88 (7%) had associated an angiographic intraluminal filling defect consistent with thrombus (group I) and were compared with the remaining 1,104 lesions (93%) without thrombus (group II). Age (56 +/- 12 vs 59 +/- 10 years) was similar in both groups, but patients in group I required more frequently dilatation after a myocardial infarction (acute phase or following thrombolytic therapy) (36% vs 12%, p less than 0.005) but infrequently for stable angina (6% vs 21%, p less than 0.005). Left ventricular ejection fraction (60 +/- 13% vs 63 +/- 12%) and the number of diseased vessels (1.46 +/- 0.7 vs 1.58 +/- 0.8) were similar in groups I and II, respectively, but lesions in group I were less frequently located in the left anterior descending coronary artery (35% vs 53%, p less than 0.025). Furthermore, lesions in group I were more frequently total occlusions (35% vs 4%, p less than 0.001), and were more severe (94 +/- 6% vs 87 +/- 8%, p less than 0.005), eccentric (81% vs 54%, p less than 0.005), irregular (72% vs 32%, p less than 0.005) and more frequently located at bend points (31% vs 17%, p less than 0.05). Primary angiographic success was lower in group I (79% vs 92%, p less than 0.001) and, after dilatation, the incidence of luminal irregularities (34% vs 15%, p less than 0.001) and early reocclusion (10% vs 1%, p less than 0.05) was higher in this group. However, when patients presenting with total occlusions were excluded from both groups primary angiographic success was similar (90% vs 91%) for groups I and II, respectively. We conclude that: 1) Lesions with intracoronary thrombus usually present other unfavourable angiographic characteristics for dilatation. 2) Results of coronary angioplasty in lesions with thrombus are similar to those obtained in other lesions when totally occluded vessels are excluded.

Angioplasty, Balloon, Coronary↗
PubMed1990

Percutaneous transluminal coronary angioplasty after non-Q-wave acute myocardial infarction.

The value of percutaneous transluminal coronary angioplasty (PTCA) for ischemia after a non-Q-wave acute myocardial infarction (AMI) was assessed prospectively in 33 consecutive patients. In 30 patients the indication for the procedure was post-AMI angina and 3 patients underwent PTCA for silent ischemia. A total of 43 lesions were attempted at 63 +/- 94 days after the non-Q-wave AMI. Primary PTCA success was obtained in 30 (91%) patients and no major complications occurred. Angiographic evaluation was performed either for symptoms or for protocol (7 +/- 1 months after PTCA) in 28 (93%) of the 30 patients with successful PTCA, but 2 patients (7%) who were asymptomatic refused the repeat angiogram. Twenty (71%) had no restenosis and 8 (29%) had restenosis. Of these, 5 patients with restenosis underwent a successful repeat PTCA (6 +/- 1 months after the initial procedure). At the last clinical follow-up (17 +/- 8 months), 2 of the 30 (7%) patients successfully dilated presented with stable angina despite medical treatment, whereas the rest (93%) remained asymptomatic. During the study period no patient died, had an AMI or required coronary artery bypass grafting. Thus, selected patients with ischemia after a non-Q-wave AMI, a "high-risk population," can be effectively treated with PTCA with an initial success rate and angiographic restenosis rate similar to that of the general PTCA population and appear to have sustained symptomatic benefit remaining free of subsequent cardiac events.

Angina Pectoris↗
PubMed1990

Repeat coronary angioplasty during the same angiographic diagnosis of coronary restenosis.

To determine whether any differences exist in results of treatment of restenosis with repeat angioplasty when the procedure is performed during diagnosis or, as an alternative, when it is performed as a separate elective procedure, we prospectively compared the outcome of 48 consecutive procedures (including 51 lesions) at the time of initial cardiac catheterization (group 1) with the outcome of 26 consecutive elective procedures (including 30 lesions) (group 2). Before control angiography was performed, the anatomic and procedural characteristics of the previous dilatation and the new symptomatic status were carefully reevaluated in all patients. Baseline clinical and angiographic characteristics including age, sex, ejection fraction, and number of diseased vessels in which repair was attempted were similar in both groups. Reasons for angioplasty were also similar with unstable angina being the most frequent indication: 29 (60%) in group 1 versus 13 (50%) in group 2. (p = NS). Morphology of the lesions was also similar, although longer lesions (greater than 12 mm) were dilated in group 2 (13 (43%) vs 10 (20%) in group 1; p less than 0.05). Angiographic success was achieved in 51 lesions (100%) in group 1 versus 28 (93%) in group 2 (p = NS). Primary angioplasty success (in the absence of major complications) was achieved in 46 (95%) procedures in group 1 versus 24 (92%) in group 2 (p = NS). Two patients in group 1 had a myocardial infarction, but there were no other major complications in either group. Preliminary data suggest that the outcome of repeat coronary angioplasty for restenosis is similar whether it is performed at the time of diagnostic catheterization or later on as an independent elective procedure.

Aged↗
PubMed1990

Cooperation between tumor necrosis factor (TNF) and platelet-activating factor (PAF) in the inflammatory response.

In this paper we have examined the cooperation between TNF and PAF in the generation of superoxide anion (O2-) in vitro by polymorphonuclear cells (PMNs), as well as their ability to induce joint inflammation when injected into the knee of healthy rabbits. TNF and PAF directly stimulated the generation of a small amount of O2- by PMNs. TNF pretreatment of PMNs induced a certain synergy in the O2- production, when these cells were later stimulated with PAF. When PAF receptor antagonists were added, the O2- release was inhibited. The injection of either TNF or PAF into the knee joint of normal rabbits induced a dose-dependent accumulation of leukocytes in the synovial cavity 24 h after administration. When TNF was administered 1 h before PAF, a synergistic response in the accumulation of leukocytes in the joint fluid was noted. The administration of BN 52726 by the intraperitoneal route markedly inhibited the cell accumulation induced by TNF and PAF. Histological signs of inflammation were noted in the synovial lining of joints injected with TNF and PAF. These results suggest that TNF can amplify the inflammatory response induced by PAF. PAF antagonists can inhibit this effect and thus may be of therapeutic value in different pathological situations.

Animals↗
PubMed1990

[Coronary angioplasty on calcified lesions].

To assess the value of coronary angioplasty in calcified lesions we have prospectively compared the clinical, procedural and anatomic characteristics of 55 calcified lesions (group A) with 830 lesions without calcium (group B). Patients in group A were older (67.2 +/- 8 vs 58.8 +/- 11 years), had a higher incidence of 3 vessel disease (20% vs 8%, p less than 0.05), and received less frequently a complete revascularization (50% vs 68%, p less than 0.05). Lesions in group A were more frequently located in the left anterior descending coronary artery and tended to be longer (0.86 +/- 0.5 vs 0.67 +/- 0.5 cm, p less than 0.1) whereas were rare at distal segments (9% vs 19%, p less than 0.05). In addition, group A lesions were more eccentric (81% vs 58%, p less than 0.05), more irregular (67% vs 33%, p less than 0.05), and frequently were located at bifurcation (42% vs 26%, p less than 0.05). More balloon inflations were required in group A (4.1 +/- 2.4 vs 3.1 +/- 1.4, p less than 0.05), but the maximal pressures utilized were similar in both groups (7.9 +/- 2.5 vs 7.6 +/- 1.9 atm). Dilatation success was achieved in 80% of the lesions in group A vs 90.1% in group B (p less than 0.05). Univariate analysis revealed a trend towards a higher restenosis rate--per lesion--in group A (42.8% vs 30.5%, p less than 0.1), which was not longer present after step-wise logistic regression analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1990

[Characteristics of coronary angioplasty in young patients].

To assess the characteristics and efficacy of coronary angioplasty in young people (less than 40 years old) (YCA) we have compared the clinical and anatomic characteristics, and the results of 27 YCA (35 lesions), with those of 732 procedures (854 lesions) performed in patients older than 40 years of age (NYCA). Clinical indication for dilatation were similar in both groups, but YCA were performed more frequently during an acute myocardial infarction (18.5 vs 4.5%, p less than 0.005). In addition, lesions in NYCA were frequently located in the left anterior descending coronary artery (51% vs 31%, p less than 0.05) were more eccentric (61% vs 37%, p less than 0.025) and tended to be more irregular (37% vs 26%, NS), and calcified (6.5% vs 0%, NS) than lesions in YCA, which more frequently presented a total occlusion (23% vs 8%, p less than 0.005) and tended to be longer (7.7 +/- 4.5 vs 6.8 +/- 4.7 mm, NS). Furthermore, YCA had a more complete coronary revascularization than NYCA (84% vs 66%, p less than 0.05). Angioplasty success per lesion (88.6% vs 89.5%), or procedure (77.8% vs 87%), was similar in both groups. The number of acute reocclusions was higher in YCA (8.6 vs 2%, p less than 0.05), but when patients with acute myocardial infarction were excluded from the analysis this difference was not longer present. Angiographic control was available in 20 YCA lesions (9 [45%] with restenosis) and in 567 NYCA lesions (178 [31%] with restenosis, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Role of intraoperative echo-Doppler color echocardiography in cardiac surgery. Preliminary study].

Intraoperative echocardiography with Doppler color flow imaging technique can provide the surgeon with an immediate and direct assessment of cardiac anatomy and function. To determine the utility of this recent technique, we have examined 15 patients pre, per, and postoperatively with Doppler color flow imaging. The intraoperative study was performed before and after cardiopulmonary bypass. A sterile transducer was placed directly on the epicardial surface of the heart, and multiple views were recorded. Intraoperative echocardiography with Doppler color flow imaging technique demonstrated excellent correlation with preoperative and postoperative findings, allowing an immediate evaluation of the surgical results. These preliminary results suggest that intraoperative Doppler color flow imaging technique is a valuable adjunct in heart surgery. It is particularly useful in valve repair, and in surgical repair of congenital heart disease.

Cardiac Surgical Procedures↗