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Biomedical subjects

I Moussa

Publications and source records attributed to I Moussa.

At least 19 recordsLinked to original sources
PubMed2006

In vitro and in vivo antiplasmodial activity of Momordica balsamina alone or in a traditional mixture.

BACKGROUND: Because of the dramatic situation of malaria in Africa, there is an urgent need to find new and cheap drugs, such as herbal medicines. Here we report the study of the in vitro and in vivo antimalarial activity of Momordica balsamina alone or in a traditional mixture used in Niger. METHODS: Extracts were obtained with different solvents and tested in vitro on Plasmodium falciparum and in vivo on Plasmodium vinckei. RESULTS: The best extracts are methanolic and present promising results in vivo by intraperitoneal and oral administration. CONCLUSION: The antimalarial activity of M. balsamina, traditionally used in Niger, is confirmed in vitro and in vivo without any toxicity in healthy mice.

Animals↗
PubMed2002

Impact of final coronary flow velocity reserve on late outcome following stent implantation.

Aims To assess whether coronary flow velocity reserve following stent implantation is predictive of the subsequent need of target lesion revascularization. Methods and Results The outcome was examined of 417 patients enrolled in a multicentre prospective randomized study (DESTINI), who received a successful single vessel stent implantation in native coronary arteries and in whom coronary flow velocity reserve was measured. Logistic regression analysis and the receiver operator characteristic curve were used. When compared with 358 patients not requiring target lesion revascularization, 59 patients (14%) who underwent target lesion revascularization had a lower final coronary flow velocity reserve (2.33 +/- 0.87 vs 2.48+/- 0.80, P= 0.20) and smaller final minimal lumen diameter (2.62 +/- 0.66 mm vs 2.73+/- 0.60, P= 0.19); however, those differences were not statistically significant. Patients with a coronary flow velocity reserve of < 2.0 (n=109, 26%) exhibited a significantly higher target lesion revascularization rate than patients with a coronary flow velocity reserve of > or = 2.0 (22% vs 11%, P= 0.010). This difference remained significant (odds ratio=2.01, 95% CI=1.11 to 3.66) after adjustment for other variables that were also correlated with the incidence of target lesion revascularization. Conclusion The presence of a final coronary flow velocity reserve of < 2.0 is an independent predictor of the need for target lesion revascularization after stent implantation in native coronary artery lesions.

Blood Flow Velocity↗
PubMed2001

Intravascular ultrasound-guided percutaneous transluminal coronary angioplasty with provisional spot stenting for treatment of long coronary lesions.

OBJECTIVES: The purpose of this study was to evaluate the approach of intravascular ultrasound (IVUS)-guided percutaneous transluminal coronary angioplasty (PTCA) with spot stenting (SS) for the treatment of long coronary lesions. BACKGROUND: Treating long coronary lesions with balloon angioplasty results in suboptimal short- and long-term outcomes. Full lesion coverage with traditional stenting (TS) has been associated with a high restenosis rate. METHODS: We prospectively evaluated a consecutive series of 130 long lesions (>15 mm) in 101 patients treated with IVUS-guided PTCA and SS. The results were compared with those of TS in a matched group of patients. Coronary angioplasty was performed with a balloon to vessel ratio of 1:1, according to the IVUS media-to-media diameter of the vessel at the lesion site, to achieve prespecified IVUS criteria: lumen cross-sectional area (CSA) > or =5.5 mm(2) or > or =50% of the vessel CSA at the lesion site. The stents were implanted only in the vessel segment where the criteria were not met. RESULTS: In the SS group, stents were implanted in 67 of 130 lesions, and the mean stent length was shorter than that of lesions in the matched TS group (10.4 +/- 13 mm vs. 32.4 +/- 13 mm, p < 0.005). The 30-day major adverse cardiac event (MACE) rate was similar (5%) for both groups. Angiographic restenosis was 25% with IVUS-guided SS, as compared with 39% in the TS group (p < 0.05). Follow-up MACE and target lesion revascularization rates were lower in the SS group than in the TS group (22% vs. 38% [p < 0.05] and 19% vs. 34% [p < 0.05], respectively). CONCLUSIONS: Intravascular ultrasound-guided SS for the treatment of long coronary lesions is associated with good acute outcome. Angiographic restenosis and follow-up MACE rates were significantly lower than those with TS.

Aged↗
PubMed2001

Validity of duplex ultrasound as a diagnostic modality for internal carotid artery disease.

There is an increasing trend to rely on duplex ultrasound rather than angiography to measure an internal carotid artery stenosis. The aim of this study was to determine the validity of ultrasound assessment of carotid stenosis performed in community based vascular laboratories. We compared ultrasound with angiography in 225 patients referred to us for carotid intervention. Mild lesions were diagnosed by ultrasound with a sensitivity of 54%, specificity of 89%, and a positive predictive value of 89% compared with angiography. Severe lesions had a sensitivity of 93%, a specificity of 67%, and a positive predictive value of 45%. Receiver operator characteristic curves demonstrated the optimal ultrasound cut-off value of 66% stenosis as a predictor of >60% stenosis measured angiographically, is associated with a false positive rate of 38%, and a false negative rate of 9%. Similarly, if a cut-off of 76% on ultrasound is used to predict >70% stenosis measured angiographically, it would be associated with a 29% false positive rate and a false negative rate of 11%. Despite the value of non-invasive testing for carotid disease, duplex ultrasonography performed in non-accredited and some accredited laboratories may produce highly variable results. Using ultrasound as the sole diagnostic test to determine the severity of a carotid stenosis may result in a high number of inappropriate operations and a large proportion of patients who may not be offered treatment due to false negative diagnoses.

Aged↗
PubMed2001

Integrated minimally invasive approaches for the treatment of atherosclerotic vascular diseases: Hybrid procedures.

Patients may develop simultaneous symptoms of atherosclerotic vascular disease from different arterial beds. A concurrent minimally invasive approach to the management of these clinical situations may be an advantage over conventional surgical procedures. This study describes two separate case series of patients undergoing coronary/peripheral (n = 38) and peripheral/peripheral procedures (n = 10). Technical and clinical success was achieved in all patients. There were two periprocedural complications (retroperitoneal bleed and septicemia) in the coronary/peripheral series and no complications in the peripheral/peripheral series. We also present five case reports to illustrate the utility of hybrid procedures in various clinical settings. This study suggests that the use of simultaneous or sequential minimally invasive procedures appears to be a safe and feasible strategy for the treatment of patients with symptoms from more than one vascular bed. Cathet Cardiovasc Intervent 2001;52:154-161.

Aged↗
PubMed2001

Cutting balloon angioplasty for the treatment of in-stent restenosis: a matched comparison with rotational atherectomy, additional stent implantation and balloon angioplasty.

OBJECTIVES: The purpose of the study was to determine whether cutting balloon angioplasty (CBA) has advantages over other modalities in treatment of in-stent restenosis (ISR). BACKGROUND: Controversies exist regarding optimal treatment for ISR. Recently, CBA emerged as a tool in management of ISR. METHODS: A total of 648 lesions treated for ISR were divided into four groups according to the treatment strategy: CBA, rotational atherectomy (ROTA), additional stenting (STENT), and percutaneous transluminal coronary angioplasty (PTCA). Following the matching process, 258 lesions were entered into the analysis. RESULTS: Baseline clinical and angiographic characteristics were similar among the groups (p = NS). Acute lumen gain was significantly higher in the STENT group (2.12 +/- 0.7 mm), whereas in the CBA group the gain was similar to one achieved following ROTA and following PTCA (1.70 +/- 0.6 vs. 1.79 +/- 0.5 mm and 1.56 +/- 0.7 mm, respectively; p = NS). The lumen loss at follow-up was lower for the CBA versus ROTA and versus STENT (0.63 +/- 0.6 vs. 1.30 +/- 0.8 mm and 1.36 +/- 0.8 mm, respectively; p < 0.0001), yielding a lower recurrent restenosis rate (20% vs. 35.9% and 41.4%, respectively; p < 0.05). By multivariate analysis, CBA (odds ratio [OR] = 0.17; confidence interval [CI], 0.06 to 0.51; p = 0.001) and diffuse restenosis type at baseline (OR = 2.07; CI, 1.15 to 3.71; p = 0.02) were identified as predictors of target lesion revascularization. CONCLUSIONS: We conclude that CBA is a safe and efficient technique for treatment of ISR, with immediate results similar to atheroablation and better clinical and angiographic outcomes at follow-up. This approach might be implemented as a viable option in management of focal ISR and to prepare diffuse ISR for brachytherapy treatment.

Aged↗
PubMed2001

Dissection flap protruding through stent struts.

A 64-year-old male with unstable angina underwent direct stenting in the proximal and mid-left anterior descending coronary artery (LAD) lesions. Although coronary angiography showed a good result, intravascular ultrasound imaging revealed a dissection flap protruding through the struts of the stent in the proximal LAD. Another stent was deployed in the first stent (stent-in-stent) to seal it. The patient's in-hospital course was uneventful. Subacute stent thrombosis was not observed.

Angina, Unstable↗
PubMed2001

Negative remodeling at the ostium of the left circumflex artery.

We report an ostial lesion with negative remodeling. Coronary angiography revealed a 60% stenosis at the ostium of the left circumflex artery (LCX). Intravascular ultrasound (IVUS)-guided directional atherectomy followed by stenting was planned. However, IVUS images revealed no significant stenosis and negative remodeling at the ostium of the LCX. The lesion did not undergo intervention.

Coronary Angiography↗
PubMed2000

Effect of intracoronary gamma-radiation therapy on in-stent restenosis: An intravascular ultrasound analysis from the gamma-1 study.

BACKGROUND: The aim of this study was to use serial volumetric intravascular ultrasound to evaluate the effect of gamma-radiation on recurrent in-stent restenosis. METHODS AND RESULTS: After successful reintervention, patients were randomized to receive either (192)Ir or placebo. Intravascular ultrasound studies with motorized pullback (0.5 mm/s) were performed immediately after irradiation and at 8-month follow-up in 70 patients. Paired volumetric analysis of the stented segment and of 5-mm proximal and distal reference segments was performed; this included measurements of the external elastic membrane, lumen, plaque and media (external elastic membrane minus lumen), stent, and intimal hyperplasia (stent minus lumen). Baseline proximal reference, stent, and distal reference measurements were similar in both groups. The changes in proximal and distal reference measurements of the external elastic membrane, plaque and media, and lumen areas were similar in both groups. However, the decrease in stented segment lumen volume was less in the (192)Ir patients than the placebo patients (-25+/-34 mm(3) versus -48+/-42 mm(3); P:=0.0225), and the increase in the volume of intimal hyperplasia in the stented segment was less in the (192)Ir patients than in the placebo patients (28+/-37 mm(3) versus 50+/-40 mm(3); P:=0.0352). When averaged over the length of the stented segment (32+/-13 mm versus 33+/-14 mm; P:=0.9), the increase in mean area of intimal hyperplasia was 0.8+/-1.0 mm(2) in the (192)Ir group and 1.6+/-1.2 mm(2) in the control group (P:=0.0065). Late stent-vessel wall malapposition was noted in one placebo patient and no (192)Ir patients. CONCLUSIONS: gamma-Radiation therapy can effectively prevent recurrent in-stent restenosis by inhibiting neointimal formation within the stent. At the stent edge, there were no significant differences between (192)Ir and placebo patients.

Analysis of Variance↗
PubMed2000

Randomized comparison of elective stent implantation and coronary balloon angioplasty guided by online quantitative angiography and intracoronary Doppler. DESTINI Study Group (Doppler Endpoint STenting INternational Investigation).

BACKGROUND: The purpose of this study was to compare long-term outcomes of coronary stenting in all lesions (elective stenting) or only in lesions with inadequate morphological and functional results after balloon angioplasty (guided PTCA). METHODS AND RESULTS: Treatment of multivessel disease, with any lesion length and vessel size, was allowed provided that all lesions were suitable for stent implantation. Patients were randomized to elective stent implantation (n=370) or guided PTCA (n=365). An optimal PTCA result (residual diameter stenosis </=35%, coronary flow reserve measured with a Doppler guidewire >2.0, absence of threatening dissections) was achieved in 166 lesions (43%). The remaining 218 lesions underwent stent implantation (provisional stenting). Final residual diameter stenosis was lower in the elective and provisional stent groups (9.3% and 10.2%) than in the optimal PTCA group (24.8%, P:<0. 00001). On an intention-to-treat analysis, the probability of >/=1 major adverse cardiac event at 12 months was 17.8% in the elective stenting group and 18.9% in the guided PTCA group (20.1% for optimal PTCA and 18.0% for the provisional stenting subgroup, P:=NS). The incidence of repeat target lesion revascularization at 1 year was 14. 9% in the elective stent group and 15.6% in the guided PTCA group (17.6% for optimal PTCA and 14.1% for the provisional stenting subgroup, P:=NS). CONCLUSIONS: When balloon angioplasty is guided by online quantitative angiography and Doppler-derived coronary flow reserve, with provisional stenting reserved for suboptimal results, early and late clinical outcomes are comparable to those achieved by elective stenting of all patients.

Angiography↗
PubMed2000

Procedural costs of digital vs. analog archiving of diagnostic cardiac catheterizations.

The use of digital technology in the cardiac catheterization laboratory is expanding at a rapid pace. The cost-effectiveness of this new technology is yet to be proven. The aims of this study were to determine the direct cost differences of digital versus analog media (CDs) for the storage of diagnostic cardiac catheterizations and to explore the factors influencing these differences. Procedural costs of all diagnostic angiograms (n = 109), from three physicians, performed in an analog catheterization laboratory (room A) and a digital catheterization laboratory (room C) were compared during a 9-month period. The mean procedural cost was higher in room A than in room C ($1,102 vs. $1,087, P < 0.001). This cost difference was eliminated when recording media costs were excluded from analysis ($1,079 vs. $1,080, P = 0.931). Therefore, we conclude there is a procedural cost savings in a cardiac catheterization room that uses digital CDs versus cineangiogram film as the archival media. Cathet. Cardiovasc. Intervent. 49:246-250, 2000.

Cardiac Catheterization↗
PubMed2000

The skirt technique: A stenting technique to treat a lesion immediately proximal to the bifurcation (pseudobifurcation).

We report a new stenting technique employed in 10 patients to treat lesions immediately proximal to a bifurcation (pseudobifurcation). A stent is mounted on two balloon catheters and advanced into the lesion immediately proximal to the bifurcation until the distal portion of the balloon catheters enters each branch at the bifurcation. This is followed by kissing balloon inflation for stent deployment. In all 10 cases, the final angiogram showed a good result at the lesion site and no ostial compromise of any of the branches. Cathet. Cardiovasc. Intervent. 51:347-351, 2000.

Aged↗
PubMed2000

Atherectomy plus stenting: what do we gain?

Coronary stents have improved the short and long-term outcomes of selected patients undergoing catheter-based coronary interventions. However, the use of these devices in complex coronary lesions has also created an incessant form of in-stent restenosis that still defies treatment. Plaque burden has been recognized as an important factor that may incite neo-intimal proliferation after stent implantation. Prospective non-randomized experience has shown that plaque removal prior to stent implantation using directional atherectomy is a promising approach to reduce restenosis in selected patients. However, the proof of concept awaits the results of the randomized trials. Ultimately, the clinical utility of this approach will depend upon: (1) further improvements on the current directional atherectomy device; (2) minimizing the incidence of non-Q-wave myocardial infarction with selective use of IIb-IIIa platelet receptor antagonists or distal protection devices; (3) targeting patients at high risk for restenosis in whom efficient debulking is feasible such as non-calcified lesions in vessels >2.75 mm and <3.5 mm in diameter that require long stents, aorto-ostial lesions, bifurcational lesions, and chronic total occlusions.

Atherectomy, Coronary↗
PubMed2000

The Efficacy of Directional Atherectomy Prior to Stent Implantation.

Coronary stents have improved the short- and long-term outcomes of patients undergoing catheter-based coronary interventions. However, the use of these devices in complex coronary lesions has also created an incessant form of in-stent restenosis that still defies treatment. Plaque burden has been consistently and reproducibly recognized as an important factor that may incite neointimal proliferation after stent implantation. Prospective nonrandomized experience has shown that plaque removal prior to stent implantation using directional atherectomy is a promising approach to reduce restenosis in selected patients. However, the proof of concept awaits the results of the randomized trials. Ultimately, the clinical use (safety and efficacy) of this approach will depend on 1) further improvements on the current directional atherectomy device to make it user friendly; 2) minimizing the incidence of non-Q-wave myocardial infarction with selective use of IIb-IIIa platelet receptor antagonists or distal protection devices; and 3) targeting patients at high risk for restenosis in whom efficient debulking is feasible. This would include patients who have noncalcified lesions in vessels greater than 2.75 mm but less than 3.5 mm in diameter that require a long stent or multiple stents, aorto-ostial lesions, bifurcational lesions, and chronic total occlusions.

Journal Article↗
PubMed1999

Effectiveness of clopidogrel and aspirin versus ticlopidine and aspirin in preventing stent thrombosis after coronary stent implantation.

BACKGROUND: Ticlopidine has been shown to reduce the incidence of stent thrombosis compared with warfarin, but it may cause serious hematological side effects. Clopidogrel, a new thienopyridine derivative, may be a safe alternative to ticlopidine. The aim of this study was to compare the safety and efficacy of clopidogrel and aspirin with those of ticlopidine and aspirin in patients undergoing coronary stent implantation. METHODS AND RESULTS: The population of this study consisted of 2 groups: patients who underwent coronary stenting and were treated with ticlopidine and aspirin (TA group, n=1406), and patients who underwent coronary stenting followed by treatment with clopidogrel and aspirin (CA group, n=283). At 1-month follow-up, there was no difference in stent thrombosis (1.5% versus 1.4%, P=1.0) or major adverse cardiac events (3.1% versus 2.4%, P=0. 85) between the TA and CA groups, respectively. The probability of any side effect (neutropenia, diarrhea, rash) was significantly higher in the TA group (10.6% versus 5.3%, P=0.006; relative risk, 0. 53; CI, 0.32 to 0.86). CONCLUSIONS: These data suggest that clopidogrel may be an effective pharmacological regimen after coronary stent implantation. Furthermore, the simpler dosing regimen, the absence of neutropenia, and the lower frequency of other side effects make it a safe alternative to ticlopidine.

Aged↗