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F Airoldi

Publications and source records attributed to F Airoldi.

14 recordsLinked to original sources
PubMed2001

Intravascular ultrasound criteria for the assessment of the functional significance of intermediate coronary artery stenoses and comparison with fractional flow reserve.

The functional significance of coronary artery stenoses of intermediate severity is important in determining strategy in patient care. Intravascular ultrasound (IVUS) is often used to evaluate coronary stenosis severity. However, at present, few data are available about the role IVUS in the assessment of functional significance of intermediate lesions. Myocardial fractional flow reserve (FFR) <0.75 is a reliable index of a functionally severe coronary stenosis. In 53 lesions we assessed (1) by pressure wire: FFR (index of functional significance), and (2) by IVUS: minimal lumen cross-sectional area (MLA, square millimeters), minimal lumen diameter (MLD, millimeters), lesion length (millimeters), and percent area stenosis at the lesion site. By regression analysis, percent area stenosis and lesion length had a significant inverse correlation with FFR (r = -0.58, p <0.001, r = -0.41, p <0.004, respectively). MLD and MLA showed a significant positive relation with FFR (r = 0.51, p <0.001, r = 0.41, p <0.004, respectively). By using a receiver operating characteristic (ROC) curve, we identified a percent area stenosis > 70% (sensitivity 100%, specificity 68%), a MLD < or = 1.8 mm (sensitivity 100%, specificity 66%), a MLA < or =4.0 mm2 (sensitivity 92%, specificity 56%), and a lesion length of >10 mm (sensitivity 41%, specificity 80%) to be the best cut-off values to fit with a FFR <0.75. The combined evaluation of both percent area stenosis and MLD made the IVUS examination more specific (sensitivity 100%, specificity 76%). In 53 intermediate coronary lesions found by angiography, IVUS area stenosis >70%, MLD < or =1.8 mm, MLA < or =4.0 mm2, and lesion length > 10 mm reliably identified functionally critical intermediate coronary stenoses.

Cardiac Catheterization↗
PubMed2001

Surgical and percutaneous myocardial angiogenesis induction. Part II--neoangiogenesis.

Coronary artery bypass surgery and angioplasty provide symptomatic relief in patients with ischemic heart disease, but despite advancement in technique and devices, these methods are not applicable to a subset of patients with angina refractory to medical treatment. Bypass surgery might not be feasible because of lack of suitable conduits, diffuse coronary disease or poor distal run-off, and coronary angioplasty is sometimes not applicable due to chronic total occlusion, diffuse disease or extreme tortuosity. We have previously reviewed the available experience with laser-induced direct myocardial revascularization, one of the new potential treatment modalities for this patient subset. One of the potential mechanisms of action for laser treatment is the induction of neoangiogenesis. In the second part of our article we review the available experience with the induction of myocardial angiogenesis using different growth factors or the genes encoding for them.

Coronary Disease↗
PubMed2000

Angioplasty of atherosclerotic and fibromuscular renal artery stenosis: time course and predicting factors of the effects on renal function.

The effects of percutaneous transluminal renal angioplasty (PTRA) on the renal function of stenotic kidneys are usually assessed by evaluating the changes in serum creatinine, which is quite a rough indicator of glomerular filtration rate (GFR). In 27 hypertensive patients with 19 atherosclerotic and 11 fibromuscular significant renal artery stenoses, we investigated with renal scintigraphy the short-term (5 days) and long-term (10 months) effects of a technically successful PTRA (in seven cases combined with a stent implantation) on GFR of the stenotic and contralateral kidneys; these measurements were combined with those of plasma renin activity (PRA) and of angiotensin II (AII). We found that in short-term studies after PTRA GFR rose from 29.7 +/- 3.5 to 34.6 +/- 3.1 mL/min and from 36.9 +/- 4.0 to 45.1 +/- 4.3 mL/min, respectively, in atherosclerotic and fibromuscular poststenotic kidneys. In long-term studies GFR further and significantly increased, to 37.8 +/- 3.2 mL/min in the former group, whereas it stabilized in the latter group (46.0 +/- 3.6 mL/min). In patients with fibromuscular stenosis these changes in GFR were associated with clear-cut reductions in blood pressure (BP), PRA, and AII; these decrements also occurred in patients with atherosclerotic stenosis but to a much lesser extent. We also found that in short- and long-term studies the percent of PTRA-induced increments of GFR in the poststenotic kidneys were inversely correlated with the baseline values of GFR. In addition, the absolute and percent increments of GFR were positively correlated with the basal levels of AII. Thus the time course of the improvement in GFR after angioplasty may differ in kidneys, depending on the etiology of the stenosis, in that in those with fibromuscular stenosis it was entirely apparent within a few days whereas in those with atherosclerotic stenosis it required several months to be fully expressed. Also, it appears that the more compromised kidneys are those that benefit most from the dilatation and that AII levels are useful indicators of the possibility that the stenotic kidney will have a favorable functional outcome in terms of restoration of renal blood flow.

Adolescent↗
PubMed2000

Plasma endothelin levels: a meaningless number?

Endothelin (ET)-1 is a potent vasoactive peptide which is mostly secreted toward the vessel wall and the circulatory levels of which are quite low; for these reasons changes in plasma ET-1 may be difficult to detect even after the application of strong stimuli, which, in theory, should profoundly alter its production. We have examined the effects of a number of such stimuli and found that in humans the only one which consistently increased plasma ET-1 was the exposure to hypobaric hypoxia; moreover under these circumstances the increments in plasma ET-1 were correlated with the changes in pulmonary systolic pressure, suggesting a role of circulating ET-1 in the adaptation of pulmonary vessels to high altitude. In contrast no consistent changes of ET-1 were observed in response to sympathetic activation induced either by exposure to cold, standing, reduction in blood pressure and blood withdrawal. In response to angioplasty of renal artery stenosis a concomitant reduction in plasma ET-1 and angiotensin II (AngII) was observed in patients who, prior to angioplasty, had a high degree of activation of the renin system, supporting the possibility that in these specific conditions AngII may actually stimulate ET-1 production in vivo.

Adaptation, Physiological↗
PubMed2000

Progressive decrease of outflow gradient and septum thickness after percutaneous alcoholization of the interventricular septum in hypertrophic obstructive cardiomyopathy.

BACKGROUND: The aim of this study was to evaluate the immediate- and mid-term results of percutaneous transluminal septal myocardial ablation (PTSMA) of the interventricular septum performed in 15 consecutive patients with hypertrophic obstructive cardiomyopathy between 1996 and 1999. METHODS: Prior to intervention, all patients (7 males, 8 females, mean age 62 +/- 11 years) complained of severe dyspnea (NYHA functional class III-IV) despite medical treatment with beta-blockers and/or verapamil. Family history of hypertrophic cardiomyopathy was present in 2 cases. Dehydrated alcohol (4.8 +/- 1.5 ml/pt) was selectively infused into the first septal perforator artery through over-the-wire balloon catheters. In 5 patients a second or a third septal branch was treated because the intraventricular gradient persisted above 50 mmHg after the initial alcohol infusion. RESULTS: Alcohol infusion induced an average peak creatine phosphokinase level of 1,524 +/- 427 IU/l. No iterating ventricular arrhythmias occurred during the procedure or in the 2-3 days of continuous ECG monitoring after the procedure. Two patients (13%) developed a complete atrioventricular block after the procedure, requiring permanent double-chamber pacing. Electrocardiographic changes included a > 2 mm ST segment elevation and transient right bundle branch block or left anterior/left posterior hemiblock in all patients. Peak basal intraventricular gradient decreased from 80 +/- 27 to 24 +/- 27 mmHg (p < 0.01) during cardiac catheterization and from 81 +/- 27 to 35 +/- 25 mmHg (p < 0.01) at the echocardiographic control performed during the hospital stay. At follow-up (mean 5.1 +/- 3.6 months), all patients were in NYHA functional class I or II. Repeat echocardiography showed a further significant decrease in intraventricular gradient to 25 +/- 26 mmHg (p < 0.01) and a progressive decrease in intraventricular septum thickness (25 +/- 5 mm before treatment, 21 +/- 6 mm before hospital discharge, 17 +/- 3 mm at follow-up, p < 0.01). CONCLUSIONS: PTSMA of the intraventricular septum effectively relieves symptoms in selected patients with hypertrophic obstructive cardiomyopathy. The immediate decrease in intraventricular gradient is followed by a further decline at follow-up with a progressive reduction in the intraventricular septum thickness.

Aged↗
PubMed2000

Surgical and percutaneous myocardial angiogenesis induction. Part I--laser revascularization.

Coronary artery bypass surgery and angioplasty provide symptomatic relief in patients with ischemic heart disease, but despite advancement in technique and devices, these methods are not applicable in a subset of patients with angina refractory to medical treatment. Bypass surgery may not be feasible because of lack of suitable conduits, diffuse coronary artery disease or poor distal run-off, and coronary angioplasty is sometimes not applicable due to chronic total occlusion, diffuse disease or extreme tortuosity. Transmyocardial laser revascularization and the stimulation of neoangiogenesis by a variety of growth factors have recently emerged as a new tool in the management of these patients. In the first part of this article, we review laser-induced direct myocardial revascularization, its indications, potential risks, and published clinical trials. The induction of neoangiogenesis using different growth factors or the genes encoding for them will be the subject of the second part of our review.

Angina Pectoris↗
PubMed1999

Prevention of distal embolization during saphenous vein graft lesion angioplasty. Experience with a new temporary occlusion and aspiration system.

BACKGROUND: Repeat coronary artery bypass graft surgery (CABG) is associated with a high morbidity and mortality, rendering percutaneous treatment of saphenous vein graft (SVG) lesions an attractive alternative. However, percutaneous interventions of degenerated SVGs carries high risk of distal embolization. METHODS AND RESULTS: This study reports our initial experience with the PercuSurge GuardWire, a new device developed to prevent embolization during treatment of degenerated SVG. This device consists of a 190-cm-long, hollow 0.014-in guidewire with a central lumen connected to a distal occlusion balloon. A dedicated inflation device (the MicroSeal Adapter) was used to inflate the distal balloon and maintain complete lumen occlusion during balloon dilatation and stent implantation. A monorail aspiration catheter, connected to a vacuum syringe, was used to evacuate atherosclerotic and thrombotic debris. Angioplasty with stent implantation was performed in 15 degenerated SVGs (18 lesions). Procedural success was achieved in all patients with normal postprocedure flow (Thrombolysis in Myocardial Infarction grade 3). No distal embolization was observed. There were no major in-hospital adverse clinical events, including Q-wave or non-Q-wave myocardial infarction, emergency CABG, or death. All patients were asymptomatic at discharge. CONCLUSIONS: This preliminary series supports the feasible use of the PercuSurge GuardWire for retrieval of plaque debris and prevention of embolization in degenerated SVGs. The good tolerance of temporary occlusions without angiographic or clinical evidence of distal embolization represents encouraging early findings.

Aged↗
PubMed1999

Successful treatment of a bifurcation lesion with the Carina Bard stent: A case report.

In the last years new techniques and user-friendly stents have improved the results of stent implantation in coronary bifurcational lesions but difficulties in stent deployment and incomplete coverage of the bifurcation remain a problem. We describe the case of a proximal lesion of the anterior descending artery involving a large diagonal branch treated with the Carina Bard bifurcate stent, a new device that allows the complete immediate coverage of a bifurcational lesion with a single stent. Cathet. Cardiovasc. Intervent. 48:89-92, 1999.

Coronary Angiography↗
PubMed1999

Renovascular hypertension. Clinical and diagnostic clues.

Renovascular hypertension (RVH), although relatively rare, is the most frequent among the secondary forms of arterial hypertension; in addition interventional radiology has remarkably increased, because of its relative invasiveness, the possibilities of treating and in many cases curing RVH bypassing the traditional surgical approach. For these reasons in recent years a number of screening tests has been developed and added to renal angiography and to the measurement of plasma renin which, still now, represent the reference methods among the morphological and the functional tests respectively. These new and promising techniques include the magnetic resonance angiography, the spiral computed tomography, the renal scintigraphy and the ultrasound scanning of renal arteries with the associated measurement of velocimetric indices. In selected populations all these methods have been shown to possess an high specificity and sensitivity but if applied to a general population of hypertensive patients their positive predictive values are going to be necessarily low because of the low prevalence of the disease. Accordingly, it is mandatory for the physician, before sending patients to these investigations, to preselect those who, on the basis of a thorough clinical examination are more likely to harbour a renal artery stenosis.

Diagnosis, Differential↗
PubMed1998

Effects of balloon angioplasty and stent implantation on intrarenal echo-Doppler velocimetric indices.

This study was aimed at examining whether four intrarenal echo-Doppler velocimetric indices (pulsatility and resistive indices, acceleration and acceleration time) can be useful for assessing the effects of renal artery dilation obtained with either angioplasty or stent implantation. Echo-Doppler studies were performed in 63 hypertensive patients with 68 renal artery stenoses (39 atherosclerotic and 29 fibromuscular) prior to and within five days after the dilation procedures (55 angioplasties, 13 stent implantations), which resulted in an average reduction of arterial narrowing from 79% to 20%. In 24 patients, the velocimetric indices were also examined in relationship to the venoarterial differences of plasma renin activity and of angiotensin II across the stenotic kidneys. We found that after dilation the values of the four indices had returned within the normal range in all but three arteries (one false negative for resistive index and two for acceleration time). However, decrements in acceleration time was the only factor to be significantly correlated with the reduction of arterial narrowing. Moreover, postdilation values of this index were, on average, slightly but significantly higher in arteries that at follow-up developed restenosis rather than in those that remained patent. For similar reductions in arterial narrowing the absolute changes of all indices were similar in atherosclerotic and fibromuscular stenotic arteries and, in a subset of the atheromatous arteries, were also similar after angioplasty and stent implantation. No relationship was found with the changes in the venoarterial differences of plasma renin activity and angiotensin II. It appears that these intrarenal velocimetric indices and, in particular, acceleration time reliably reflect the technical success of renal artery dilation. The acceleration time index may also be valuable for predicting the restenosis of the dilated vessel. None of the indices, however, mirrors the functional consequences of removal of renal artery stenosis as expressed through the changes in transrenal gradients of the components of the renin-angiotensin system.

Adolescent↗
PubMed1998

Bifurcational stenting.

Treatment of bifurcation lesions is a complex issue, and there is no single panacea to the variety of lesions that form this cohort. The contribution of side-branch compromise to the adverse clinical events occurring after stent implantation need not be stressed and requires an aggressive approach including balloon dilatation before and after stent deployment. Various new techniques of kissing stent placement, such as the 'T', 'V', 'Y', and the culottes technique, have been proposed in recent years to treat different anatomical situations. The angle formed by the side-branches, the severity of involvement of the ostia and the vessel size are the main factors which influence selection of the strategy. Newer generations of stents, such as the bifurcate stents, tailor-made for bifurcation lesions, are evolving, and are expected to make a positive impact on the procedural outcomes and long-term results after bifurcation stenting. The development of new strategies and stent designs has greatly improved safety and immediate outcome of bifurcational stenting, but the procedural success still needs to be matched by an equal improvement in long-term patency.

Angioplasty, Balloon, Coronary↗
PubMed1996

Superiority of acceleration and acceleration time over pulsatility and resistance indices as screening tests for renal artery stenosis.

OBJECTIVE: To compare the accuracy of four echo-Doppler-derived velocimetric indices (pulsatility and resistance indices, acceleration and acceleration time) in detecting renal artery stenosis in hypertensive patients. PATIENTS AND METHODS: In 73 hospitalized patients with moderate-to-severe hypertension, 18 of whom had normal renal arteries and 55 renal artery stenosis (50-95%) either atherosclerotic (30 cases, five bilateral) or fibromuscular dysplasia (25 cases, two bilateral), we measured the four velocimetric indices using the lateral abdominal approach and sampling Doppler waveforms distally to the stenosis. The diagnostic accuracy of each index was calculated using as cut-off limit the ideal threshold determined with the receiver-operating characteristic curves. RESULTS: On average all of the indices were altered significantly in arteries with stenosis of both aetiologies with respect to normal arteries, the alterations of pulsatility and resistance indices being, however, less pronounced than those of acceleration and acceleration time, particularly in atherosclerotic stenosis. With the cut-off limits of 0.93, 0.59 and 7.4 m/s2 and 60 ms, respectively, for pulsatility and resistance indices, acceleration and acceleration time, their diagnostic accuracies were 80, 73, 93 and 92%. In stenotic arteries, only the acceleration time was correlated with the degree of arterial narrowing, whereas, in normal arteries, only pulsatility and resistance indices were directly correlated with the age of patients. CONCLUSIONS: Acceleration and acceleration time are more accurate indices than pulsatility and resistance to screen for renal artery stenosis, probably because their alterations are less attenuated by the counterbalancing effects of age and of atherosclerosis.

Acceleration↗