Vassilis Voudris

Prediction of Restenosis After Coronary Angioplasty by Use of a New Index TIMI Frame Count/Minimal Luminal Diameter Ratio

BACKGROUNDnIt has been shown recently that postangioplasty coronary flow reserve and the degree of residual stenosis have a modest predictive value for short- and long-term clinical outcomes after coronary angioplasty. Corrected TIMI frame count (CTFC) is a simple quantitative index of coronary blood flow. Its relationship with Doppler coronary flow velocity and clinical outcome after coronary angioplasty has not been fully clarified. The aim of this study was to identify clinical, angiographic, and functional predictors of clinical and angiographic restenosis after conventional coronary angioplasty.nnnMETHODS AND RESULTSnWe studied 70 consecutive patients in whom intracoronary Doppler flow-velocity measurements were performed before and after angioplasty. Patients were evaluated for restenosis by clinical follow-up, exercise stress test/(201)Tl scintigraphy, and follow-up angiography, which was performed at 10. 5+/-10.3 months in 63 patients. According to the results of univariate analysis, a new index, postangioplasty CTFC/minimal luminal diameter (MLD) ratio, was created. Multivariate analysis revealed that CTFC/MLD ratio was the only independent predictor of angiographic (OR 2.02; 95% CI 1.37 to 2.97; P<0.0004) and clinical (OR 1.60; 95% CI 1.15 to 2.21; P<0.005) restenosis. The receiver operating characteristic curve area of this index was 79% for angiographic and 73% for clinical restenosis. The optimal CTFC/MLD ratio cutoff values were 7.88 for angiographic and 7.94 for clinical restenosis, respectively.nnnCONCLUSIONSnOur data indicate that postangioplasty CTFC/MLD ratio, which incorporates both the angiographic and functional features of coronary lesions, is a reliable, objective, and inexpensive index for prediction of angiographic and clinical restenosis after conventional coronary angioplasty.

Usefulness of flow reserve in the left internal mammary artery to determine graft patency to the left anterior descending coronary artery

Two-dimensional Doppler echocardiography (DE) and intravascular Doppler-tipped guidewire (flowire) have been used to measure flow in aortocoronary conduits at rest and during hyperemia, but they have not been compared. We investigated which flow velocity parameters obtained with these 2 different techniques can predict left internal mammary artery (LIMA) graft patency. Twenty-nine patients with previous coronary artery bypass grafting referred for evaluation of symptoms of coronary artery disease were studied after cardiac catheterization using the flowire and DE. Proximal LIMA graft flow velocity was measured at rest and during hyperemia produced by 140 microg/kg/min of intravenous adenosine infusion over 6 minutes with both methods. Normal LIMA grafts and left anterior descending artery (LAD) distal to the anastomosis were present in 16 patients, whereas 13 had >70% graft or native vessel stenosis. The coronary flow velocity reserve (r = 0.79) and the diastolic-to-systolic velocity ratio during hyperemia (r = 0.73) correlated very well between the 2 techniques. Among the variables obtained with the 2 techniques, the intragraft coronary flow velocity reserve measured by both methods was the only independent predictor of graft/recipient LAD patency. This variable had a sensitivity and specificity of 86% at a cutoff point of 2.07 with the flowire method and 83% at a cutoff point of 1.54 with DE. The areas below the receiver-operating characteristic curves were 0.91 and 0.93, respectively. Coronary flow velocity reserve measurements obtained with DE appears a reliable noninvasive method for assessing LIMA graft and/or LAD distal to the anastomosis patency in patients after bypass surgery and correlate very well with those directly obtained by intravascular Doppler.

Genetic diversity of RANTES gene promoter and susceptibility to coronary artery disease and restenosis after percutaneous coronary intervention

Regulated on activation, normal T cell expressed and secreted (RANTES) gene promoter is a regulatory region and a site of notable genetic diversity. In order to explore a possible interaction between RANTES promoter genetic diversity and susceptibility to coronary artery disease (CAD) and in stent restenosis (ISR), we initially sequenced a locus extending from -516 to 40 covering the entire region of the RANTES promoter in 100 subjects randomly selected from our cohort. Four single nucleotide polymorphisms (SNPs) were identified: -403G/A, -256G/A, -109C/T and -28C/G. The frequency of the -109C/T and -256G/A variations was <0.01, and was considered to be of limited significance. The frequency of the -403G/A and -28C/G polymorphisms was evaluated in the entire sample, which consisted of 118 patients subjected to percutaneous coronary intervention (PCI) without ISR on angiographic re-evaluation (no IRS group), 74 CAD patients with ISR on angiographic re-evaluation (IRS group) and 146 controls without angiographic evidence of CAD (no CAD group). No association was established between the RANTES promoter genotype and ISR. A genotype-phenotype interaction was observed between the -403G/A polymorphism and CAD. The -403A homozygotes were significantly more common in the CAD group than in the controls. The severity of CAD among case subjects, expressed as the mean number of diseased vessels, was significantly higher among -403A homozygotes as compared to wild-type homozygotes and heterozygotes. In conclusion, the RANTES -403A allele was associated with the presence and severity of CAD independently of conventional cardiovascular risk factors. The RANTES promoter genotype did not influence susceptibility to ISR in patients subjected to PCI.

Genetic diversity of the KCNE1 gene and susceptibility to postoperative atrial fibrillation.

BACKGROUNDnThe human KCNE1 protein forms the β-subunit of the IKs potassium channel and is important in the regulation of the atrial action potential duration. The purpose of this study was to investigate the association between the nonsynonymous 112G>A mutation of the KCNE1 gene and postcardiac surgery atrial fibrillation (AF).nnnMETHODS AND RESULTSnA cohort of patients scheduled for cardiac surgery was prospectively recruited. The genotype of 112G>A polymorphism was determined using polymerase chain reaction/restriction fragment analysis and confirmed with direct sequencing of the polymerase chain reaction product. In total, 509 patients were recruited in the study, of whom 203 (39.9%) had at least 1 qualifying episode of postoperative AF. An increased frequency of the G allele was observed in the postoperative AF group compared with the group without postoperative AF (0.628 vs 0.552, respectively, P = .016). The individuals relative risk of postoperative AF increased as the number of G alleles increased from 1.36 (95% CI 0.89-2.08) for G allele heterozygotes to 1.62 (95% CI 1.08-2.43) for G allele homozygotes (P = .04 for trend). The multivariate analysis revealed the abnormal ejection fraction (odds ratio [OR] 1.585, 95% CI 1.076-2.331, P = .020), age (OR 1.043, 95% CI 1.022-1.064, P < .001), type of surgery (aortic valve replacement) (OR 1.869, 95% CI 1.094-3.194, P = .022), and the 112G>A genotype (OR 1.401 [in additive model], 95% CI 1.052-1.865, P = .021) to be independent predictors of postoperative AF.nnnCONCLUSIONnThis study confirmed the association of the 112G>A polymorphism and postoperative AF in a cohort of patients undergoing cardiac surgery.

Long-term clinical outcome of coronary artery stenting in elderly patients.

BackgroundThe elderly constitute a rapidly expanding segment of our population and cardiovascular disease becomes more prevalent with increasing age. Existing data have shown that percutaneous coronary interventions in the elderly are associated with an increase risk of in-hospital complications compared to younger patients. In the present study we retrospectively assessed the long-term clinical outcome of coronary artery stenting in an elderly population and compared them with the cohort of younger patients. MethodsThe study population included 402 consecutive patients with coronary artery disease who underwent coronary artery stenting; of these 69 were elderly (age >u200970 years, group I) and 333 were younger (age ≤u200970 years, group II). Percutaneous coronary intervention combined with stent implantation was performed using standard techniques. Clinical outcomes during follow-up (24u2009±u200913 months, range 7–56 months) were obtained in all patients without major in-hospital complications. Survival curves and multivariate Cox proportional hazard models for any late clinical event were reported. ResultsNo difference in in-hospital complications or clinical success rate was observed between the two groups of patients. Complete revascularization was obtained more frequently in younger compared to elderly patients (Pu2009<u20090.05). At 2 years, event-free survival was 62% in the elderly and 76% in younger patients (Pu2009<u20090.001); this difference was mostly made-up by recurrence of angina in the elderly. Impaired left ventricular systolic function (ejection fraction <u200940%) was an independent predictor of late death. ConclusionsCoronary artery stenting is an effective therapeutic strategy in elderly with coronary artery disease and is associated with good short- and long-term results. Age per se should not preclude patients from undergoing coronary stenting.

Blood flow velocity in donor coronary artery depends on the degree and pattern of collateral vessel development: a study using thrombolysis in myocardial infarction frame count method.

To understand the influence of collateral vessels on the coronary flow, TIMI frame count (TFC) method was applied as a measure of mean coronary blood flow velocity in artery giving collateral blood supply to the other artery in angiograms of 76 patients with single occluded coronary artery: RCA giving collaterals to occluded LAD or LAD giving collaterals to occluded RCA. As a control group, TFC was applied in angiograms of 30 patients with mild or no coronary artery disease. TFC was lower (faster blood flow) in LAD giving collaterals to occluded RCA (43 patients) than in LAD in control group (21.8 ± 10.5 vs. 33.9 ± 20.8 frames; P < 0.01). Higher degree of collateral vessels (Rentrop classification) and mixed‐ and distal‐type collaterals (through the interventricular septum and heart apex) was associated with lower TFC. There was no difference in TFC in the RCA giving collaterals to an occluded LAD (33 patients) compared to the TFC in RCA in control group (16.6 ± 9.0 vs. 18.5 ± 6.0; P = NS), even in angiograms with higher degree of collateral vessel development. TFC was lower (faster blood flow) only in subgroups with mixed (proximal and distal types together in the same patient) and distal (through the interventricular septum and the apex of the heart) collateral types. A delayed contrast appearance in occluded LAD compared to occluded RCA has been found (35.1 ± 16.1 vs. 20.2 ± 7.3 frames; P < 0.001) with earlier contrast appearance in occluded LAD when proximal collateral vessels (through the conal and acute marginal branches of RCA) were presented. The coronary flow in donor arteries depends not only on the degree but also on the pattern of collateral vessels. The simple TFC method may facilitate the study of collateral filling pattern and offer insight into the influence of collaterals on the ventricular function. Catheter Cardiovasc Interv 2003;60:462–468.

Intracoronary irradiation and stent placement in a chronic total coronary occlusion: long-term clinical, angiographic, and intracoronary ultrasound follow-up.

Intracoronary irradiation emerges as a promising method in a variety of restenosis prone coronary lesions. We report the acute and long‐term clinical, angiographic, and ICUS follow‐up of a patient who underwent a successful angioplasty with stent placement in a chronic coronary occlusion with adjuvant γ‐intracoronary radiation. Cathet. Cardiovasc. Intervent. 51:199–202, 2000.

Diabetes mellitus and unstable coronary artery disease: improved clinical outcome of coronary artery stenting in an era of glycoprotein IIb/IIIa inhibitors and lipid-lowering therapy.

ObjectiveThe short- and long-term clinical outcomes of coronary artery stenting in diabetic patients with unstable coronary artery disease were assessed and compared with a cohort of non-diabetic patients in the context of platelet glycoprotein IIb/IIIa inhibitors and lipid-lowering therapy. MethodsThe study population comprised 252 consecutive patients with unstable angina who underwent coronary artery stenting; of these 46 were diabetic and 206 were non-diabetic. In-hospital results and clinical outcome during follow-up (24±13 months, range 7–56 months) were obtained in all patients without major in-hospital complications. Survival curves and multivariate models for any late clinical event were reported. ResultsA high clinical success rate and no difference in in-hospital complications between the two groups of patients were observed. Complete revascularization rate was similar in diabetic and non-diabetic patients (48% compared with 52%). A greater proportion of diabetic than non-diabetic patients received IIb/IIIa inhibitors during the procedure and lipid-lowering drugs at hospital discharge (87% compared with 46%, P=0.001 and 83% compared with 61%, P=0.006 respectively). At 2-year clinical follow-up, the incidences of death and myocardial infarction were similar in both groups; the need for any revascularization was only slightly higher in diabetic patients (P=NS). Incomplete revascularization and multi-vessel disease were independent predictors of any revascularization. ConclusionsCoronary artery stenting combined with glycoprotein IIb/IIIa inhibitor infusion and long-term lipid-lowering therapy is an effective therapeutic strategy in diabetic patients with unstable coronary artery disease and is associated with good short- and long-term results, comparable to those observed in non-diabetic patients.